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/* Expands front end tree to back end RTL for GNU C-Compiler
Copyright (C) 1987, 88, 89, 91-96, 1997 Free Software Foundation, Inc.
This file is part of GNU CC.
GNU CC is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 2, or (at your option)
any later version.
GNU CC is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with GNU CC; see the file COPYING. If not, write to
the Free Software Foundation, 59 Temple Place - Suite 330,
Boston, MA 02111-1307, USA. */
/* This file handles the generation of rtl code from tree structure
at the level of the function as a whole.
It creates the rtl expressions for parameters and auto variables
and has full responsibility for allocating stack slots.
`expand_function_start' is called at the beginning of a function,
before the function body is parsed, and `expand_function_end' is
called after parsing the body.
Call `assign_stack_local' to allocate a stack slot for a local variable.
This is usually done during the RTL generation for the function body,
but it can also be done in the reload pass when a pseudo-register does
not get a hard register.
Call `put_var_into_stack' when you learn, belatedly, that a variable
previously given a pseudo-register must in fact go in the stack.
This function changes the DECL_RTL to be a stack slot instead of a reg
then scans all the RTL instructions so far generated to correct them. */
#include "config.h"
#include <stdio.h>
#include "rtl.h"
#include "tree.h"
#include "flags.h"
#include "except.h"
#include "function.h"
#include "insn-flags.h"
#include "expr.h"
#include "insn-codes.h"
#include "regs.h"
#include "hard-reg-set.h"
#include "insn-config.h"
#include "recog.h"
#include "output.h"
#include "basic-block.h"
#include "obstack.h"
#include "bytecode.h"
#include "bc-emit.h"
#ifndef TRAMPOLINE_ALIGNMENT
#define TRAMPOLINE_ALIGNMENT FUNCTION_BOUNDARY
#endif
/* Some systems use __main in a way incompatible with its use in gcc, in these
cases use the macros NAME__MAIN to give a quoted symbol and SYMBOL__MAIN to
give the same symbol without quotes for an alternative entry point. You
must define both, or neither. */
#ifndef NAME__MAIN
#define NAME__MAIN "__main"
#define SYMBOL__MAIN __main
#endif
/* Round a value to the lowest integer less than it that is a multiple of
the required alignment. Avoid using division in case the value is
negative. Assume the alignment is a power of two. */
#define FLOOR_ROUND(VALUE,ALIGN) ((VALUE) & ~((ALIGN) - 1))
/* Similar, but round to the next highest integer that meets the
alignment. */
#define CEIL_ROUND(VALUE,ALIGN) (((VALUE) + (ALIGN) - 1) & ~((ALIGN)- 1))
/* NEED_SEPARATE_AP means that we cannot derive ap from the value of fp
during rtl generation. If they are different register numbers, this is
always true. It may also be true if
FIRST_PARM_OFFSET - STARTING_FRAME_OFFSET is not a constant during rtl
generation. See fix_lexical_addr for details. */
#if ARG_POINTER_REGNUM != FRAME_POINTER_REGNUM
#define NEED_SEPARATE_AP
#endif
/* Number of bytes of args popped by function being compiled on its return.
Zero if no bytes are to be popped.
May affect compilation of return insn or of function epilogue. */
int current_function_pops_args;
/* Nonzero if function being compiled needs to be given an address
where the value should be stored. */
int current_function_returns_struct;
/* Nonzero if function being compiled needs to
return the address of where it has put a structure value. */
int current_function_returns_pcc_struct;
/* Nonzero if function being compiled needs to be passed a static chain. */
int current_function_needs_context;
/* Nonzero if function being compiled can call setjmp. */
int current_function_calls_setjmp;
/* Nonzero if function being compiled can call longjmp. */
int current_function_calls_longjmp;
/* Nonzero if function being compiled receives nonlocal gotos
from nested functions. */
int current_function_has_nonlocal_label;
/* Nonzero if function being compiled has nonlocal gotos to parent
function. */
int current_function_has_nonlocal_goto;
/* Nonzero if function being compiled contains nested functions. */
int current_function_contains_functions;
/* Nonzero if the current function is a thunk (a lightweight function that
just adjusts one of its arguments and forwards to another function), so
we should try to cut corners where we can. */
int current_function_is_thunk;
/* Nonzero if function being compiled can call alloca,
either as a subroutine or builtin. */
int current_function_calls_alloca;
/* Nonzero if the current function returns a pointer type */
int current_function_returns_pointer;
/* If some insns can be deferred to the delay slots of the epilogue, the
delay list for them is recorded here. */
rtx current_function_epilogue_delay_list;
/* If function's args have a fixed size, this is that size, in bytes.
Otherwise, it is -1.
May affect compilation of return insn or of function epilogue. */
int current_function_args_size;
/* # bytes the prologue should push and pretend that the caller pushed them.
The prologue must do this, but only if parms can be passed in registers. */
int current_function_pretend_args_size;
/* # of bytes of outgoing arguments. If ACCUMULATE_OUTGOING_ARGS is
defined, the needed space is pushed by the prologue. */
int current_function_outgoing_args_size;
/* This is the offset from the arg pointer to the place where the first
anonymous arg can be found, if there is one. */
rtx current_function_arg_offset_rtx;
/* Nonzero if current function uses varargs.h or equivalent.
Zero for functions that use stdarg.h. */
int current_function_varargs;
/* Nonzero if current function uses stdarg.h or equivalent.
Zero for functions that use varargs.h. */
int current_function_stdarg;
/* Quantities of various kinds of registers
used for the current function's args. */
CUMULATIVE_ARGS current_function_args_info;
/* Name of function now being compiled. */
char *current_function_name;
/* If non-zero, an RTL expression for the location at which the current
function returns its result. If the current function returns its
result in a register, current_function_return_rtx will always be
the hard register containing the result. */
rtx current_function_return_rtx;
/* Nonzero if the current function uses the constant pool. */
int current_function_uses_const_pool;
/* Nonzero if the current function uses pic_offset_table_rtx. */
int current_function_uses_pic_offset_table;
/* The arg pointer hard register, or the pseudo into which it was copied. */
rtx current_function_internal_arg_pointer;
/* The FUNCTION_DECL for an inline function currently being expanded. */
tree inline_function_decl;
/* Number of function calls seen so far in current function. */
int function_call_count;
/* List (chain of TREE_LIST) of LABEL_DECLs for all nonlocal labels
(labels to which there can be nonlocal gotos from nested functions)
in this function. */
tree nonlocal_labels;
/* RTX for stack slot that holds the current handler for nonlocal gotos.
Zero when function does not have nonlocal labels. */
rtx nonlocal_goto_handler_slot;
/* RTX for stack slot that holds the stack pointer value to restore
for a nonlocal goto.
Zero when function does not have nonlocal labels. */
rtx nonlocal_goto_stack_level;
/* Label that will go on parm cleanup code, if any.
Jumping to this label runs cleanup code for parameters, if
such code must be run. Following this code is the logical return label. */
rtx cleanup_label;
/* Label that will go on function epilogue.
Jumping to this label serves as a "return" instruction
on machines which require execution of the epilogue on all returns. */
rtx return_label;
/* List (chain of EXPR_LISTs) of pseudo-regs of SAVE_EXPRs.
So we can mark them all live at the end of the function, if nonopt. */
rtx save_expr_regs;
/* List (chain of EXPR_LISTs) of all stack slots in this function.
Made for the sake of unshare_all_rtl. */
rtx stack_slot_list;
/* Chain of all RTL_EXPRs that have insns in them. */
tree rtl_expr_chain;
/* Label to jump back to for tail recursion, or 0 if we have
not yet needed one for this function. */
rtx tail_recursion_label;
/* Place after which to insert the tail_recursion_label if we need one. */
rtx tail_recursion_reentry;
/* Location at which to save the argument pointer if it will need to be
referenced. There are two cases where this is done: if nonlocal gotos
exist, or if vars stored at an offset from the argument pointer will be
needed by inner routines. */
rtx arg_pointer_save_area;
/* Offset to end of allocated area of stack frame.
If stack grows down, this is the address of the last stack slot allocated.
If stack grows up, this is the address for the next slot. */
HOST_WIDE_INT frame_offset;
/* List (chain of TREE_LISTs) of static chains for containing functions.
Each link has a FUNCTION_DECL in the TREE_PURPOSE and a reg rtx
in an RTL_EXPR in the TREE_VALUE. */
static tree context_display;
/* List (chain of TREE_LISTs) of trampolines for nested functions.
The trampoline sets up the static chain and jumps to the function.
We supply the trampoline's address when the function's address is requested.
Each link has a FUNCTION_DECL in the TREE_PURPOSE and a reg rtx
in an RTL_EXPR in the TREE_VALUE. */
static tree trampoline_list;
/* Insn after which register parms and SAVE_EXPRs are born, if nonopt. */
static rtx parm_birth_insn;
#if 0
/* Nonzero if a stack slot has been generated whose address is not
actually valid. It means that the generated rtl must all be scanned
to detect and correct the invalid addresses where they occur. */
static int invalid_stack_slot;
#endif
/* Last insn of those whose job was to put parms into their nominal homes. */
static rtx last_parm_insn;
/* 1 + last pseudo register number used for loading a copy
of a parameter of this function. */
static int max_parm_reg;
/* Vector indexed by REGNO, containing location on stack in which
to put the parm which is nominally in pseudo register REGNO,
if we discover that that parm must go in the stack. */
static rtx *parm_reg_stack_loc;
/* Nonzero once virtual register instantiation has been done.
assign_stack_local uses frame_pointer_rtx when this is nonzero. */
static int virtuals_instantiated;
/* These variables hold pointers to functions to
save and restore machine-specific data,
in push_function_context and pop_function_context. */
void (*save_machine_status) PROTO((struct function *));
void (*restore_machine_status) PROTO((struct function *));
/* Nonzero if we need to distinguish between the return value of this function
and the return value of a function called by this function. This helps
integrate.c */
extern int rtx_equal_function_value_matters;
extern tree sequence_rtl_expr;
/* In order to evaluate some expressions, such as function calls returning
structures in memory, we need to temporarily allocate stack locations.
We record each allocated temporary in the following structure.
Associated with each temporary slot is a nesting level. When we pop up
one level, all temporaries associated with the previous level are freed.
Normally, all temporaries are freed after the execution of the statement
in which they were created. However, if we are inside a ({...}) grouping,
the result may be in a temporary and hence must be preserved. If the
result could be in a temporary, we preserve it if we can determine which
one it is in. If we cannot determine which temporary may contain the
result, all temporaries are preserved. A temporary is preserved by
pretending it was allocated at the previous nesting level.
Automatic variables are also assigned temporary slots, at the nesting
level where they are defined. They are marked a "kept" so that
free_temp_slots will not free them. */
struct temp_slot
{
/* Points to next temporary slot. */
struct temp_slot *next;
/* The rtx to used to reference the slot. */
rtx slot;
/* The rtx used to represent the address if not the address of the
slot above. May be an EXPR_LIST if multiple addresses exist. */
rtx address;
/* The size, in units, of the slot. */
int size;
/* The value of `sequence_rtl_expr' when this temporary is allocated. */
tree rtl_expr;
/* Non-zero if this temporary is currently in use. */
char in_use;
/* Non-zero if this temporary has its address taken. */
char addr_taken;
/* Nesting level at which this slot is being used. */
int level;
/* Non-zero if this should survive a call to free_temp_slots. */
int keep;
/* The offset of the slot from the frame_pointer, including extra space
for alignment. This info is for combine_temp_slots. */
int base_offset;
/* The size of the slot, including extra space for alignment. This
info is for combine_temp_slots. */
int full_size;
};
/* List of all temporaries allocated, both available and in use. */
struct temp_slot *temp_slots;
/* Current nesting level for temporaries. */
int temp_slot_level;
/* The FUNCTION_DECL node for the current function. */
static tree this_function_decl;
/* Callinfo pointer for the current function. */
static rtx this_function_callinfo;
/* The label in the bytecode file of this function's actual bytecode.
Not an rtx. */
static char *this_function_bytecode;
/* The call description vector for the current function. */
static rtx this_function_calldesc;
/* Size of the local variables allocated for the current function. */
int local_vars_size;
/* Current depth of the bytecode evaluation stack. */
int stack_depth;
/* Maximum depth of the evaluation stack in this function. */
int max_stack_depth;
/* Current depth in statement expressions. */
static int stmt_expr_depth;
/* This structure is used to record MEMs or pseudos used to replace VAR, any
SUBREGs of VAR, and any MEMs containing VAR as an address. We need to
maintain this list in case two operands of an insn were required to match;
in that case we must ensure we use the same replacement. */
struct fixup_replacement
{
rtx old;
rtx new;
struct fixup_replacement *next;
};
/* Forward declarations. */
static struct temp_slot *find_temp_slot_from_address PROTO((rtx));
static void put_reg_into_stack PROTO((struct function *, rtx, tree,
enum machine_mode, enum machine_mode,
int));
static void fixup_var_refs PROTO((rtx, enum machine_mode, int));
static struct fixup_replacement
*find_fixup_replacement PROTO((struct fixup_replacement **, rtx));
static void fixup_var_refs_insns PROTO((rtx, enum machine_mode, int,
rtx, int));
static void fixup_var_refs_1 PROTO((rtx, enum machine_mode, rtx *, rtx,
struct fixup_replacement **));
static rtx fixup_memory_subreg PROTO((rtx, rtx, int));
static rtx walk_fixup_memory_subreg PROTO((rtx, rtx, int));
static rtx fixup_stack_1 PROTO((rtx, rtx));
static void optimize_bit_field PROTO((rtx, rtx, rtx *));
static void instantiate_decls PROTO((tree, int));
static void instantiate_decls_1 PROTO((tree, int));
static void instantiate_decl PROTO((rtx, int, int));
static int instantiate_virtual_regs_1 PROTO((rtx *, rtx, int));
static void delete_handlers PROTO((void));
static void pad_to_arg_alignment PROTO((struct args_size *, int));
static void pad_below PROTO((struct args_size *, enum machine_mode,
tree));
static tree round_down PROTO((tree, int));
static rtx round_trampoline_addr PROTO((rtx));
static tree blocks_nreverse PROTO((tree));
static int all_blocks PROTO((tree, tree *));
static int *record_insns PROTO((rtx));
static int contains PROTO((rtx, int *));
/* Pointer to chain of `struct function' for containing functions. */
struct function *outer_function_chain;
/* Given a function decl for a containing function,
return the `struct function' for it. */
struct function *
find_function_data (decl)
tree decl;
{
struct function *p;
for (p = outer_function_chain; p; p = p->next)
if (p->decl == decl)
return p;
abort ();
}
/* Save the current context for compilation of a nested function.
This is called from language-specific code.
The caller is responsible for saving any language-specific status,
since this function knows only about language-independent variables. */
void
push_function_context_to (context)
tree context;
{
struct function *p = (struct function *) xmalloc (sizeof (struct function));
p->next = outer_function_chain;
outer_function_chain = p;
p->name = current_function_name;
p->decl = current_function_decl;
p->pops_args = current_function_pops_args;
p->returns_struct = current_function_returns_struct;
p->returns_pcc_struct = current_function_returns_pcc_struct;
p->returns_pointer = current_function_returns_pointer;
p->needs_context = current_function_needs_context;
p->calls_setjmp = current_function_calls_setjmp;
p->calls_longjmp = current_function_calls_longjmp;
p->calls_alloca = current_function_calls_alloca;
p->has_nonlocal_label = current_function_has_nonlocal_label;
p->has_nonlocal_goto = current_function_has_nonlocal_goto;
p->contains_functions = current_function_contains_functions;
p->is_thunk = current_function_is_thunk;
p->args_size = current_function_args_size;
p->pretend_args_size = current_function_pretend_args_size;
p->arg_offset_rtx = current_function_arg_offset_rtx;
p->varargs = current_function_varargs;
p->stdarg = current_function_stdarg;
p->uses_const_pool = current_function_uses_const_pool;
p->uses_pic_offset_table = current_function_uses_pic_offset_table;
p->internal_arg_pointer = current_function_internal_arg_pointer;
p->max_parm_reg = max_parm_reg;
p->parm_reg_stack_loc = parm_reg_stack_loc;
p->outgoing_args_size = current_function_outgoing_args_size;
p->return_rtx = current_function_return_rtx;
p->nonlocal_goto_handler_slot = nonlocal_goto_handler_slot;
p->nonlocal_goto_stack_level = nonlocal_goto_stack_level;
p->nonlocal_labels = nonlocal_labels;
p->cleanup_label = cleanup_label;
p->return_label = return_label;
p->save_expr_regs = save_expr_regs;
p->stack_slot_list = stack_slot_list;
p->parm_birth_insn = parm_birth_insn;
p->frame_offset = frame_offset;
p->tail_recursion_label = tail_recursion_label;
p->tail_recursion_reentry = tail_recursion_reentry;
p->arg_pointer_save_area = arg_pointer_save_area;
p->rtl_expr_chain = rtl_expr_chain;
p->last_parm_insn = last_parm_insn;
p->context_display = context_display;
p->trampoline_list = trampoline_list;
p->function_call_count = function_call_count;
p->temp_slots = temp_slots;
p->temp_slot_level = temp_slot_level;
p->fixup_var_refs_queue = 0;
p->epilogue_delay_list = current_function_epilogue_delay_list;
p->args_info = current_function_args_info;
save_tree_status (p, context);
save_storage_status (p);
save_emit_status (p);
init_emit ();
save_expr_status (p);
save_stmt_status (p);
save_varasm_status (p);
if (save_machine_status)
(*save_machine_status) (p);
}
void
push_function_context ()
{
push_function_context_to (current_function_decl);
}
/* Restore the last saved context, at the end of a nested function.
This function is called from language-specific code. */
void
pop_function_context_from (context)
tree context;
{
struct function *p = outer_function_chain;
outer_function_chain = p->next;
current_function_contains_functions
= p->contains_functions || p->inline_obstacks
|| context == current_function_decl;
current_function_name = p->name;
current_function_decl = p->decl;
current_function_pops_args = p->pops_args;
current_function_returns_struct = p->returns_struct;
current_function_returns_pcc_struct = p->returns_pcc_struct;
current_function_returns_pointer = p->returns_pointer;
current_function_needs_context = p->needs_context;
current_function_calls_setjmp = p->calls_setjmp;
current_function_calls_longjmp = p->calls_longjmp;
current_function_calls_alloca = p->calls_alloca;
current_function_has_nonlocal_label = p->has_nonlocal_label;
current_function_has_nonlocal_goto = p->has_nonlocal_goto;
current_function_is_thunk = p->is_thunk;
current_function_args_size = p->args_size;
current_function_pretend_args_size = p->pretend_args_size;
current_function_arg_offset_rtx = p->arg_offset_rtx;
current_function_varargs = p->varargs;
current_function_stdarg = p->stdarg;
current_function_uses_const_pool = p->uses_const_pool;
current_function_uses_pic_offset_table = p->uses_pic_offset_table;
current_function_internal_arg_pointer = p->internal_arg_pointer;
max_parm_reg = p->max_parm_reg;
parm_reg_stack_loc = p->parm_reg_stack_loc;
current_function_outgoing_args_size = p->outgoing_args_size;
current_function_return_rtx = p->return_rtx;
nonlocal_goto_handler_slot = p->nonlocal_goto_handler_slot;
nonlocal_goto_stack_level = p->nonlocal_goto_stack_level;
nonlocal_labels = p->nonlocal_labels;
cleanup_label = p->cleanup_label;
return_label = p->return_label;
save_expr_regs = p->save_expr_regs;
stack_slot_list = p->stack_slot_list;
parm_birth_insn = p->parm_birth_insn;
frame_offset = p->frame_offset;
tail_recursion_label = p->tail_recursion_label;
tail_recursion_reentry = p->tail_recursion_reentry;
arg_pointer_save_area = p->arg_pointer_save_area;
rtl_expr_chain = p->rtl_expr_chain;
last_parm_insn = p->last_parm_insn;
context_display = p->context_display;
trampoline_list = p->trampoline_list;
function_call_count = p->function_call_count;
temp_slots = p->temp_slots;
temp_slot_level = p->temp_slot_level;
current_function_epilogue_delay_list = p->epilogue_delay_list;
reg_renumber = 0;
current_function_args_info = p->args_info;
restore_tree_status (p, context);
restore_storage_status (p);
restore_expr_status (p);
restore_emit_status (p);
restore_stmt_status (p);
restore_varasm_status (p);
if (restore_machine_status)
(*restore_machine_status) (p);
/* Finish doing put_var_into_stack for any of our variables
which became addressable during the nested function. */
{
struct var_refs_queue *queue = p->fixup_var_refs_queue;
for (; queue; queue = queue->next)
fixup_var_refs (queue->modified, queue->promoted_mode, queue->unsignedp);
}
free (p);
/* Reset variables that have known state during rtx generation. */
rtx_equal_function_value_matters = 1;
virtuals_instantiated = 0;
}
void pop_function_context ()
{
pop_function_context_from (current_function_decl);
}
/* Allocate fixed slots in the stack frame of the current function. */
/* Return size needed for stack frame based on slots so far allocated.
This size counts from zero. It is not rounded to STACK_BOUNDARY;
the caller may have to do that. */
HOST_WIDE_INT
get_frame_size ()
{
#ifdef FRAME_GROWS_DOWNWARD
return -frame_offset;
#else
return frame_offset;
#endif
}
/* Allocate a stack slot of SIZE bytes and return a MEM rtx for it
with machine mode MODE.
ALIGN controls the amount of alignment for the address of the slot:
0 means according to MODE,
-1 means use BIGGEST_ALIGNMENT and round size to multiple of that,
positive specifies alignment boundary in bits.
We do not round to stack_boundary here. */
rtx
assign_stack_local (mode, size, align)
enum machine_mode mode;
int size;
int align;
{
register rtx x, addr;
int bigend_correction = 0;
int alignment;
if (align == 0)
{
alignment = GET_MODE_ALIGNMENT (mode) / BITS_PER_UNIT;
if (mode == BLKmode)
alignment = BIGGEST_ALIGNMENT / BITS_PER_UNIT;
}
else if (align == -1)
{
alignment = BIGGEST_ALIGNMENT / BITS_PER_UNIT;
size = CEIL_ROUND (size, alignment);
}
else
alignment = align / BITS_PER_UNIT;
/* Round frame offset to that alignment.
We must be careful here, since FRAME_OFFSET might be negative and
division with a negative dividend isn't as well defined as we might
like. So we instead assume that ALIGNMENT is a power of two and
use logical operations which are unambiguous. */
#ifdef FRAME_GROWS_DOWNWARD
frame_offset = FLOOR_ROUND (frame_offset, alignment);
#else
frame_offset = CEIL_ROUND (frame_offset, alignment);
#endif
/* On a big-endian machine, if we are allocating more space than we will use,
use the least significant bytes of those that are allocated. */
if (BYTES_BIG_ENDIAN && mode != BLKmode)
bigend_correction = size - GET_MODE_SIZE (mode);
#ifdef FRAME_GROWS_DOWNWARD
frame_offset -= size;
#endif
/* If we have already instantiated virtual registers, return the actual
address relative to the frame pointer. */
if (virtuals_instantiated)
addr = plus_constant (frame_pointer_rtx,
(frame_offset + bigend_correction
+ STARTING_FRAME_OFFSET));
else
addr = plus_constant (virtual_stack_vars_rtx,
frame_offset + bigend_correction);
#ifndef FRAME_GROWS_DOWNWARD
frame_offset += size;
#endif
x = gen_rtx (MEM, mode, addr);
stack_slot_list = gen_rtx (EXPR_LIST, VOIDmode, x, stack_slot_list);
return x;
}
/* Assign a stack slot in a containing function.
First three arguments are same as in preceding function.
The last argument specifies the function to allocate in. */
rtx
assign_outer_stack_local (mode, size, align, function)
enum machine_mode mode;
int size;
int align;
struct function *function;
{
register rtx x, addr;
int bigend_correction = 0;
int alignment;
/* Allocate in the memory associated with the function in whose frame
we are assigning. */
push_obstacks (function->function_obstack,
function->function_maybepermanent_obstack);
if (align == 0)
{
alignment = GET_MODE_ALIGNMENT (mode) / BITS_PER_UNIT;
if (mode == BLKmode)
alignment = BIGGEST_ALIGNMENT / BITS_PER_UNIT;
}
else if (align == -1)
{
alignment = BIGGEST_ALIGNMENT / BITS_PER_UNIT;
size = CEIL_ROUND (size, alignment);
}
else
alignment = align / BITS_PER_UNIT;
/* Round frame offset to that alignment. */
#ifdef FRAME_GROWS_DOWNWARD
function->frame_offset = FLOOR_ROUND (function->frame_offset, alignment);
#else
function->frame_offset = CEIL_ROUND (function->frame_offset, alignment);
#endif
/* On a big-endian machine, if we are allocating more space than we will use,
use the least significant bytes of those that are allocated. */
if (BYTES_BIG_ENDIAN && mode != BLKmode)
bigend_correction = size - GET_MODE_SIZE (mode);
#ifdef FRAME_GROWS_DOWNWARD
function->frame_offset -= size;
#endif
addr = plus_constant (virtual_stack_vars_rtx,
function->frame_offset + bigend_correction);
#ifndef FRAME_GROWS_DOWNWARD
function->frame_offset += size;
#endif
x = gen_rtx (MEM, mode, addr);
function->stack_slot_list
= gen_rtx (EXPR_LIST, VOIDmode, x, function->stack_slot_list);
pop_obstacks ();
return x;
}
/* Allocate a temporary stack slot and record it for possible later
reuse.
MODE is the machine mode to be given to the returned rtx.
SIZE is the size in units of the space required. We do no rounding here
since assign_stack_local will do any required rounding.
KEEP is 1 if this slot is to be retained after a call to
free_temp_slots. Automatic variables for a block are allocated
with this flag. KEEP is 2, if we allocate a longer term temporary,
whose lifetime is controlled by CLEANUP_POINT_EXPRs. */
rtx
assign_stack_temp (mode, size, keep)
enum machine_mode mode;
int size;
int keep;
{
struct temp_slot *p, *best_p = 0;
/* If SIZE is -1 it means that somebody tried to allocate a temporary
of a variable size. */
if (size == -1)
abort ();
/* First try to find an available, already-allocated temporary that is the
exact size we require. */
for (p = temp_slots; p; p = p->next)
if (p->size == size && GET_MODE (p->slot) == mode && ! p->in_use)
break;
/* If we didn't find, one, try one that is larger than what we want. We
find the smallest such. */
if (p == 0)
for (p = temp_slots; p; p = p->next)
if (p->size > size && GET_MODE (p->slot) == mode && ! p->in_use
&& (best_p == 0 || best_p->size > p->size))
best_p = p;
/* Make our best, if any, the one to use. */
if (best_p)
{
/* If there are enough aligned bytes left over, make them into a new
temp_slot so that the extra bytes don't get wasted. Do this only
for BLKmode slots, so that we can be sure of the alignment. */
if (GET_MODE (best_p->slot) == BLKmode)
{
int alignment = BIGGEST_ALIGNMENT / BITS_PER_UNIT;
int rounded_size = CEIL_ROUND (size, alignment);
if (best_p->size - rounded_size >= alignment)
{
p = (struct temp_slot *) oballoc (sizeof (struct temp_slot));
p->in_use = p->addr_taken = 0;
p->size = best_p->size - rounded_size;
p->base_offset = best_p->base_offset + rounded_size;
p->full_size = best_p->full_size - rounded_size;
p->slot = gen_rtx (MEM, BLKmode,
plus_constant (XEXP (best_p->slot, 0),
rounded_size));
p->address = 0;
p->rtl_expr = 0;
p->next = temp_slots;
temp_slots = p;
stack_slot_list = gen_rtx (EXPR_LIST, VOIDmode, p->slot,
stack_slot_list);
best_p->size = rounded_size;
best_p->full_size = rounded_size;
}
}
p = best_p;
}
/* If we still didn't find one, make a new temporary. */
if (p == 0)
{
int frame_offset_old = frame_offset;
p = (struct temp_slot *) oballoc (sizeof (struct temp_slot));
/* If the temp slot mode doesn't indicate the alignment,
use the largest possible, so no one will be disappointed. */
p->slot = assign_stack_local (mode, size, mode == BLKmode ? -1 : 0);
/* The following slot size computation is necessary because we don't
know the actual size of the temporary slot until assign_stack_local
has performed all the frame alignment and size rounding for the
requested temporary. Note that extra space added for alignment
can be either above or below this stack slot depending on which
way the frame grows. We include the extra space if and only if it
is above this slot. */
#ifdef FRAME_GROWS_DOWNWARD
p->size = frame_offset_old - frame_offset;
#else
p->size = size;
#endif
/* Now define the fields used by combine_temp_slots. */
#ifdef FRAME_GROWS_DOWNWARD
p->base_offset = frame_offset;
p->full_size = frame_offset_old - frame_offset;
#else
p->base_offset = frame_offset_old;
p->full_size = frame_offset - frame_offset_old;
#endif
p->address = 0;
p->next = temp_slots;
temp_slots = p;
}
p->in_use = 1;
p->addr_taken = 0;
p->rtl_expr = sequence_rtl_expr;
if (keep == 2)
{
p->level = target_temp_slot_level;
p->keep = 0;
}
else
{
p->level = temp_slot_level;
p->keep = keep;
}
/* We may be reusing an old slot, so clear any MEM flags that may have been
set from before. */
RTX_UNCHANGING_P (p->slot) = 0;
MEM_IN_STRUCT_P (p->slot) = 0;
return p->slot;
}
/* Assign a temporary of given TYPE.
KEEP is as for assign_stack_temp.
MEMORY_REQUIRED is 1 if the result must be addressable stack memory;
it is 0 if a register is OK.
DONT_PROMOTE is 1 if we should not promote values in register
to wider modes. */
rtx
assign_temp (type, keep, memory_required, dont_promote)
tree type;
int keep;
int memory_required;
int dont_promote;
{
enum machine_mode mode = TYPE_MODE (type);
int unsignedp = TREE_UNSIGNED (type);
if (mode == BLKmode || memory_required)
{
int size = int_size_in_bytes (type);
rtx tmp;
/* Unfortunately, we don't yet know how to allocate variable-sized
temporaries. However, sometimes we have a fixed upper limit on
the size (which is stored in TYPE_ARRAY_MAX_SIZE) and can use that
instead. This is the case for Chill variable-sized strings. */
if (size == -1 && TREE_CODE (type) == ARRAY_TYPE
&& TYPE_ARRAY_MAX_SIZE (type) != NULL_TREE
&& TREE_CODE (TYPE_ARRAY_MAX_SIZE (type)) == INTEGER_CST)
size = TREE_INT_CST_LOW (TYPE_ARRAY_MAX_SIZE (type));
tmp = assign_stack_temp (mode, size, keep);
MEM_IN_STRUCT_P (tmp) = AGGREGATE_TYPE_P (type);
return tmp;
}
#ifndef PROMOTE_FOR_CALL_ONLY
if (! dont_promote)
mode = promote_mode (type, mode, &unsignedp, 0);
#endif
return gen_reg_rtx (mode);
}
/* Combine temporary stack slots which are adjacent on the stack.
This allows for better use of already allocated stack space. This is only
done for BLKmode slots because we can be sure that we won't have alignment
problems in this case. */
void
combine_temp_slots ()
{
struct temp_slot *p, *q;
struct temp_slot *prev_p, *prev_q;
/* Determine where to free back to after this function. */
rtx free_pointer = rtx_alloc (CONST_INT);
for (p = temp_slots, prev_p = 0; p; p = prev_p ? prev_p->next : temp_slots)
{
int delete_p = 0;
if (! p->in_use && GET_MODE (p->slot) == BLKmode)
for (q = p->next, prev_q = p; q; q = prev_q->next)
{
int delete_q = 0;
if (! q->in_use && GET_MODE (q->slot) == BLKmode)
{
if (p->base_offset + p->full_size == q->base_offset)
{
/* Q comes after P; combine Q into P. */
p->size += q->size;
p->full_size += q->full_size;
delete_q = 1;
}
else if (q->base_offset + q->full_size == p->base_offset)
{
/* P comes after Q; combine P into Q. */
q->size += p->size;
q->full_size += p->full_size;
delete_p = 1;
break;
}
}
/* Either delete Q or advance past it. */
if (delete_q)
prev_q->next = q->next;
else
prev_q = q;
}
/* Either delete P or advance past it. */
if (delete_p)
{
if (prev_p)
prev_p->next = p->next;
else
temp_slots = p->next;
}
else
prev_p = p;
}
/* Free all the RTL made by plus_constant. */
rtx_free (free_pointer);
}
/* Find the temp slot corresponding to the object at address X. */
static struct temp_slot *
find_temp_slot_from_address (x)
rtx x;
{
struct temp_slot *p;
rtx next;
for (p = temp_slots; p; p = p->next)
{
if (! p->in_use)
continue;
else if (XEXP (p->slot, 0) == x
|| p->address == x
|| (GET_CODE (x) == PLUS
&& XEXP (x, 0) == virtual_stack_vars_rtx
&& GET_CODE (XEXP (x, 1)) == CONST_INT
&& INTVAL (XEXP (x, 1)) >= p->base_offset
&& INTVAL (XEXP (x, 1)) < p->base_offset + p->full_size))
return p;
else if (p->address != 0 && GET_CODE (p->address) == EXPR_LIST)
for (next = p->address; next; next = XEXP (next, 1))
if (XEXP (next, 0) == x)
return p;
}
return 0;
}
/* Indicate that NEW is an alternate way of referring to the temp slot
that previous was known by OLD. */
void
update_temp_slot_address (old, new)
rtx old, new;
{
struct temp_slot *p = find_temp_slot_from_address (old);
/* If none, return. Else add NEW as an alias. */
if (p == 0)
return;
else if (p->address == 0)
p->address = new;
else
{
if (GET_CODE (p->address) != EXPR_LIST)
p->address = gen_rtx (EXPR_LIST, VOIDmode, p->address, NULL_RTX);
p->address = gen_rtx (EXPR_LIST, VOIDmode, new, p->address);
}
}
/* If X could be a reference to a temporary slot, mark the fact that its
address was taken. */
void
mark_temp_addr_taken (x)
rtx x;
{
struct temp_slot *p;
if (x == 0)
return;
/* If X is not in memory or is at a constant address, it cannot be in
a temporary slot. */
if (GET_CODE (x) != MEM || CONSTANT_P (XEXP (x, 0)))
return;
p = find_temp_slot_from_address (XEXP (x, 0));
if (p != 0)
p->addr_taken = 1;
}
/* If X could be a reference to a temporary slot, mark that slot as
belonging to the to one level higher than the current level. If X
matched one of our slots, just mark that one. Otherwise, we can't
easily predict which it is, so upgrade all of them. Kept slots
need not be touched.
This is called when an ({...}) construct occurs and a statement
returns a value in memory. */
void
preserve_temp_slots (x)
rtx x;
{
struct temp_slot *p = 0;
/* If there is no result, we still might have some objects whose address
were taken, so we need to make sure they stay around. */
if (x == 0)
{
for (p = temp_slots; p; p = p->next)
if (p->in_use && p->level == temp_slot_level && p->addr_taken)
p->level--;
return;
}
/* If X is a register that is being used as a pointer, see if we have
a temporary slot we know it points to. To be consistent with
the code below, we really should preserve all non-kept slots
if we can't find a match, but that seems to be much too costly. */
if (GET_CODE (x) == REG && REGNO_POINTER_FLAG (REGNO (x)))
p = find_temp_slot_from_address (x);
/* If X is not in memory or is at a constant address, it cannot be in
a temporary slot, but it can contain something whose address was
taken. */
if (p == 0 && (GET_CODE (x) != MEM || CONSTANT_P (XEXP (x, 0))))
{
for (p = temp_slots; p; p = p->next)
if (p->in_use && p->level == temp_slot_level && p->addr_taken)
p->level--;
return;
}
/* First see if we can find a match. */
if (p == 0)
p = find_temp_slot_from_address (XEXP (x, 0));
if (p != 0)
{
/* Move everything at our level whose address was taken to our new
level in case we used its address. */
struct temp_slot *q;
if (p->level == temp_slot_level)
{
for (q = temp_slots; q; q = q->next)
if (q != p && q->addr_taken && q->level == p->level)
q->level--;
p->level--;
p->addr_taken = 0;
}
return;
}
/* Otherwise, preserve all non-kept slots at this level. */
for (p = temp_slots; p; p = p->next)
if (p->in_use && p->level == temp_slot_level && ! p->keep)
p->level--;
}
/* X is the result of an RTL_EXPR. If it is a temporary slot associated
with that RTL_EXPR, promote it into a temporary slot at the present
level so it will not be freed when we free slots made in the
RTL_EXPR. */
void
preserve_rtl_expr_result (x)
rtx x;
{
struct temp_slot *p;
/* If X is not in memory or is at a constant address, it cannot be in
a temporary slot. */
if (x == 0 || GET_CODE (x) != MEM || CONSTANT_P (XEXP (x, 0)))
return;
/* If we can find a match, move it to our level unless it is already at
an upper level. */
p = find_temp_slot_from_address (XEXP (x, 0));
if (p != 0)
{
p->level = MIN (p->level, temp_slot_level);
p->rtl_expr = 0;
}
return;
}
/* Free all temporaries used so far. This is normally called at the end
of generating code for a statement. Don't free any temporaries
currently in use for an RTL_EXPR that hasn't yet been emitted.
We could eventually do better than this since it can be reused while
generating the same RTL_EXPR, but this is complex and probably not
worthwhile. */
void
free_temp_slots ()
{
struct temp_slot *p;
for (p = temp_slots; p; p = p->next)
if (p->in_use && p->level == temp_slot_level && ! p->keep
&& p->rtl_expr == 0)
p->in_use = 0;
combine_temp_slots ();
}
/* Free all temporary slots used in T, an RTL_EXPR node. */
void
free_temps_for_rtl_expr (t)
tree t;
{
struct temp_slot *p;
for (p = temp_slots; p; p = p->next)
if (p->rtl_expr == t)
p->in_use = 0;
combine_temp_slots ();
}
/* Mark all temporaries ever allocated in this functon as not suitable
for reuse until the current level is exited. */
void
mark_all_temps_used ()
{
struct temp_slot *p;
for (p = temp_slots; p; p = p->next)
{
p->in_use = p->keep = 1;
p->level = MIN (p->level, temp_slot_level);
}
}
/* Push deeper into the nesting level for stack temporaries. */
void
push_temp_slots ()
{
temp_slot_level++;
}
/* Pop a temporary nesting level. All slots in use in the current level
are freed. */
void
pop_temp_slots ()
{
struct temp_slot *p;
for (p = temp_slots; p; p = p->next)
if (p->in_use && p->level == temp_slot_level && p->rtl_expr == 0)
p->in_use = 0;
combine_temp_slots ();
temp_slot_level--;
}
/* Initialize temporary slots. */
void
init_temp_slots ()
{
/* We have not allocated any temporaries yet. */
temp_slots = 0;
temp_slot_level = 0;
target_temp_slot_level = 0;
}
/* Retroactively move an auto variable from a register to a stack slot.
This is done when an address-reference to the variable is seen. */
void
put_var_into_stack (decl)
tree decl;
{
register rtx reg;
enum machine_mode promoted_mode, decl_mode;
struct function *function = 0;
tree context;
if (output_bytecode)
return;
context = decl_function_context (decl);
/* Get the current rtl used for this object and it's original mode. */
reg = TREE_CODE (decl) == SAVE_EXPR ? SAVE_EXPR_RTL (decl) : DECL_RTL (decl);
/* No need to do anything if decl has no rtx yet
since in that case caller is setting TREE_ADDRESSABLE
and a stack slot will be assigned when the rtl is made. */
if (reg == 0)
return;
/* Get the declared mode for this object. */
decl_mode = (TREE_CODE (decl) == SAVE_EXPR ? TYPE_MODE (TREE_TYPE (decl))
: DECL_MODE (decl));
/* Get the mode it's actually stored in. */
promoted_mode = GET_MODE (reg);
/* If this variable comes from an outer function,
find that function's saved context. */
if (context != current_function_decl && context != inline_function_decl)
for (function = outer_function_chain; function; function = function->next)
if (function->decl == context)
break;
/* If this is a variable-size object with a pseudo to address it,
put that pseudo into the stack, if the var is nonlocal. */
if (DECL_NONLOCAL (decl)
&& GET_CODE (reg) == MEM
&& GET_CODE (XEXP (reg, 0)) == REG
&& REGNO (XEXP (reg, 0)) > LAST_VIRTUAL_REGISTER)
{
reg = XEXP (reg, 0);
decl_mode = promoted_mode = GET_MODE (reg);
}
/* Now we should have a value that resides in one or more pseudo regs. */
if (GET_CODE (reg) == REG)
put_reg_into_stack (function, reg, TREE_TYPE (decl),
promoted_mode, decl_mode, TREE_SIDE_EFFECTS (decl));
else if (GET_CODE (reg) == CONCAT)
{
/* A CONCAT contains two pseudos; put them both in the stack.
We do it so they end up consecutive. */
enum machine_mode part_mode = GET_MODE (XEXP (reg, 0));
tree part_type = TREE_TYPE (TREE_TYPE (decl));
#ifdef FRAME_GROWS_DOWNWARD
/* Since part 0 should have a lower address, do it second. */
put_reg_into_stack (function, XEXP (reg, 1), part_type, part_mode,
part_mode, TREE_SIDE_EFFECTS (decl));
put_reg_into_stack (function, XEXP (reg, 0), part_type, part_mode,
part_mode, TREE_SIDE_EFFECTS (decl));
#else
put_reg_into_stack (function, XEXP (reg, 0), part_type, part_mode,
part_mode, TREE_SIDE_EFFECTS (decl));
put_reg_into_stack (function, XEXP (reg, 1), part_type, part_mode,
part_mode, TREE_SIDE_EFFECTS (decl));
#endif
/* Change the CONCAT into a combined MEM for both parts. */
PUT_CODE (reg, MEM);
MEM_VOLATILE_P (reg) = MEM_VOLATILE_P (XEXP (reg, 0));
/* The two parts are in memory order already.
Use the lower parts address as ours. */
XEXP (reg, 0) = XEXP (XEXP (reg, 0), 0);
/* Prevent sharing of rtl that might lose. */
if (GET_CODE (XEXP (reg, 0)) == PLUS)
XEXP (reg, 0) = copy_rtx (XEXP (reg, 0));
}
else
return;
if (flag_check_memory_usage)
emit_library_call (chkr_set_right_libfunc, 1, VOIDmode, 3,
XEXP (reg, 0), ptr_mode,
GEN_INT (GET_MODE_SIZE (GET_MODE (reg))),
TYPE_MODE (sizetype),
GEN_INT (MEMORY_USE_RW), QImode);
}
/* Subroutine of put_var_into_stack. This puts a single pseudo reg REG
into the stack frame of FUNCTION (0 means the current function).
DECL_MODE is the machine mode of the user-level data type.
PROMOTED_MODE is the machine mode of the register.
VOLATILE_P is nonzero if this is for a "volatile" decl. */
static void
put_reg_into_stack (function, reg, type, promoted_mode, decl_mode, volatile_p)
struct function *function;
rtx reg;
tree type;
enum machine_mode promoted_mode, decl_mode;
int volatile_p;
{
rtx new = 0;
if (function)
{
if (REGNO (reg) < function->max_parm_reg)
new = function->parm_reg_stack_loc[REGNO (reg)];
if (new == 0)
new = assign_outer_stack_local (decl_mode, GET_MODE_SIZE (decl_mode),
0, function);
}
else
{
if (REGNO (reg) < max_parm_reg)
new = parm_reg_stack_loc[REGNO (reg)];
if (new == 0)
new = assign_stack_local (decl_mode, GET_MODE_SIZE (decl_mode), 0);
}
PUT_MODE (reg, decl_mode);
XEXP (reg, 0) = XEXP (new, 0);
/* `volatil' bit means one thing for MEMs, another entirely for REGs. */
MEM_VOLATILE_P (reg) = volatile_p;
PUT_CODE (reg, MEM);
/* If this is a memory ref that contains aggregate components,
mark it as such for cse and loop optimize. */
MEM_IN_STRUCT_P (reg) = AGGREGATE_TYPE_P (type);
/* Now make sure that all refs to the variable, previously made
when it was a register, are fixed up to be valid again. */
if (function)
{
struct var_refs_queue *temp;
/* Variable is inherited; fix it up when we get back to its function. */
push_obstacks (function->function_obstack,
function->function_maybepermanent_obstack);
/* See comment in restore_tree_status in tree.c for why this needs to be
on saveable obstack. */
temp
= (struct var_refs_queue *) savealloc (sizeof (struct var_refs_queue));
temp->modified = reg;
temp->promoted_mode = promoted_mode;
temp->unsignedp = TREE_UNSIGNED (type);
temp->next = function->fixup_var_refs_queue;
function->fixup_var_refs_queue = temp;
pop_obstacks ();
}
else
/* Variable is local; fix it up now. */
fixup_var_refs (reg, promoted_mode, TREE_UNSIGNED (type));
}
static void
fixup_var_refs (var, promoted_mode, unsignedp)
rtx var;
enum machine_mode promoted_mode;
int unsignedp;
{
tree pending;
rtx first_insn = get_insns ();
struct sequence_stack *stack = sequence_stack;
tree rtl_exps = rtl_expr_chain;
/* Must scan all insns for stack-refs that exceed the limit. */
fixup_var_refs_insns (var, promoted_mode, unsignedp, first_insn, stack == 0);
/* Scan all pending sequences too. */
for (; stack; stack = stack->next)
{
push_to_sequence (stack->first);
fixup_var_refs_insns (var, promoted_mode, unsignedp,
stack->first, stack->next != 0);
/* Update remembered end of sequence
in case we added an insn at the end. */
stack->last = get_last_insn ();
end_sequence ();
}
/* Scan all waiting RTL_EXPRs too. */
for (pending = rtl_exps; pending; pending = TREE_CHAIN (pending))
{
rtx seq = RTL_EXPR_SEQUENCE (TREE_VALUE (pending));
if (seq != const0_rtx && seq != 0)
{
push_to_sequence (seq);
fixup_var_refs_insns (var, promoted_mode, unsignedp, seq, 0);
end_sequence ();
}
}
}
/* REPLACEMENTS is a pointer to a list of the struct fixup_replacement and X is
some part of an insn. Return a struct fixup_replacement whose OLD
value is equal to X. Allocate a new structure if no such entry exists. */
static struct fixup_replacement *
find_fixup_replacement (replacements, x)
struct fixup_replacement **replacements;
rtx x;
{
struct fixup_replacement *p;
/* See if we have already replaced this. */
for (p = *replacements; p && p->old != x; p = p->next)
;
if (p == 0)
{
p = (struct fixup_replacement *) oballoc (sizeof (struct fixup_replacement));
p->old = x;
p->new = 0;
p->next = *replacements;
*replacements = p;
}
return p;
}
/* Scan the insn-chain starting with INSN for refs to VAR
and fix them up. TOPLEVEL is nonzero if this chain is the
main chain of insns for the current function. */
static void
fixup_var_refs_insns (var, promoted_mode, unsignedp, insn, toplevel)
rtx var;
enum machine_mode promoted_mode;
int unsignedp;
rtx insn;
int toplevel;
{
rtx call_dest = 0;
while (insn)
{
rtx next = NEXT_INSN (insn);
rtx note;
if (GET_RTX_CLASS (GET_CODE (insn)) == 'i')
{
/* If this is a CLOBBER of VAR, delete it.
If it has a REG_LIBCALL note, delete the REG_LIBCALL
and REG_RETVAL notes too. */
if (GET_CODE (PATTERN (insn)) == CLOBBER
&& XEXP (PATTERN (insn), 0) == var)
{
if ((note = find_reg_note (insn, REG_LIBCALL, NULL_RTX)) != 0)
/* The REG_LIBCALL note will go away since we are going to
turn INSN into a NOTE, so just delete the
corresponding REG_RETVAL note. */
remove_note (XEXP (note, 0),
find_reg_note (XEXP (note, 0), REG_RETVAL,
NULL_RTX));
/* In unoptimized compilation, we shouldn't call delete_insn
except in jump.c doing warnings. */
PUT_CODE (insn, NOTE);
NOTE_LINE_NUMBER (insn) = NOTE_INSN_DELETED;
NOTE_SOURCE_FILE (insn) = 0;
}
/* The insn to load VAR from a home in the arglist
is now a no-op. When we see it, just delete it. */
else if (toplevel
&& GET_CODE (PATTERN (insn)) == SET
&& SET_DEST (PATTERN (insn)) == var
/* If this represents the result of an insn group,
don't delete the insn. */
&& find_reg_note (insn, REG_RETVAL, NULL_RTX) == 0
&& rtx_equal_p (SET_SRC (PATTERN (insn)), var))
{
/* In unoptimized compilation, we shouldn't call delete_insn
except in jump.c doing warnings. */
PUT_CODE (insn, NOTE);
NOTE_LINE_NUMBER (insn) = NOTE_INSN_DELETED;
NOTE_SOURCE_FILE (insn) = 0;
if (insn == last_parm_insn)
last_parm_insn = PREV_INSN (next);
}
else
{
struct fixup_replacement *replacements = 0;
rtx next_insn = NEXT_INSN (insn);
#ifdef SMALL_REGISTER_CLASSES
/* If the insn that copies the results of a CALL_INSN
into a pseudo now references VAR, we have to use an
intermediate pseudo since we want the life of the
return value register to be only a single insn.
If we don't use an intermediate pseudo, such things as
address computations to make the address of VAR valid
if it is not can be placed between the CALL_INSN and INSN.
To make sure this doesn't happen, we record the destination
of the CALL_INSN and see if the next insn uses both that
and VAR. */
if (SMALL_REGISTER_CLASSES)
{
if (call_dest != 0 && GET_CODE (insn) == INSN
&& reg_mentioned_p (var, PATTERN (insn))
&& reg_mentioned_p (call_dest, PATTERN (insn)))
{
rtx temp = gen_reg_rtx (GET_MODE (call_dest));
emit_insn_before (gen_move_insn (temp, call_dest), insn);
PATTERN (insn) = replace_rtx (PATTERN (insn),
call_dest, temp);
}
if (GET_CODE (insn) == CALL_INSN
&& GET_CODE (PATTERN (insn)) == SET)
call_dest = SET_DEST (PATTERN (insn));
else if (GET_CODE (insn) == CALL_INSN
&& GET_CODE (PATTERN (insn)) == PARALLEL
&& GET_CODE (XVECEXP (PATTERN (insn), 0, 0)) == SET)
call_dest = SET_DEST (XVECEXP (PATTERN (insn), 0, 0));
else
call_dest = 0;
}
#endif
/* See if we have to do anything to INSN now that VAR is in
memory. If it needs to be loaded into a pseudo, use a single
pseudo for the entire insn in case there is a MATCH_DUP
between two operands. We pass a pointer to the head of
a list of struct fixup_replacements. If fixup_var_refs_1
needs to allocate pseudos or replacement MEMs (for SUBREGs),
it will record them in this list.
If it allocated a pseudo for any replacement, we copy into
it here. */
fixup_var_refs_1 (var, promoted_mode, &PATTERN (insn), insn,
&replacements);
/* If this is last_parm_insn, and any instructions were output
after it to fix it up, then we must set last_parm_insn to
the last such instruction emitted. */
if (insn == last_parm_insn)
last_parm_insn = PREV_INSN (next_insn);
while (replacements)
{
if (GET_CODE (replacements->new) == REG)
{
rtx insert_before;
rtx seq;
/* OLD might be a (subreg (mem)). */
if (GET_CODE (replacements->old) == SUBREG)
replacements->old
= fixup_memory_subreg (replacements->old, insn, 0);
else
replacements->old
= fixup_stack_1 (replacements->old, insn);
insert_before = insn;
/* If we are changing the mode, do a conversion.
This might be wasteful, but combine.c will
eliminate much of the waste. */
if (GET_MODE (replacements->new)
!= GET_MODE (replacements->old))
{
start_sequence ();
convert_move (replacements->new,
replacements->old, unsignedp);
seq = gen_sequence ();
end_sequence ();
}
else
seq = gen_move_insn (replacements->new,
replacements->old);
emit_insn_before (seq, insert_before);
}
replacements = replacements->next;
}
}
/* Also fix up any invalid exprs in the REG_NOTES of this insn.
But don't touch other insns referred to by reg-notes;
we will get them elsewhere. */
for (note = REG_NOTES (insn); note; note = XEXP (note, 1))
if (GET_CODE (note) != INSN_LIST)
XEXP (note, 0)
= walk_fixup_memory_subreg (XEXP (note, 0), insn, 1);
}
insn = next;
}
}
/* VAR is a MEM that used to be a pseudo register with mode PROMOTED_MODE.
See if the rtx expression at *LOC in INSN needs to be changed.
REPLACEMENTS is a pointer to a list head that starts out zero, but may
contain a list of original rtx's and replacements. If we find that we need
to modify this insn by replacing a memory reference with a pseudo or by
making a new MEM to implement a SUBREG, we consult that list to see if
we have already chosen a replacement. If none has already been allocated,
we allocate it and update the list. fixup_var_refs_insns will copy VAR
or the SUBREG, as appropriate, to the pseudo. */
static void
fixup_var_refs_1 (var, promoted_mode, loc, insn, replacements)
register rtx var;
enum machine_mode promoted_mode;
register rtx *loc;
rtx insn;
struct fixup_replacement **replacements;
{
register int i;
register rtx x = *loc;
RTX_CODE code = GET_CODE (x);
register char *fmt;
register rtx tem, tem1;
struct fixup_replacement *replacement;
switch (code)
{
case MEM:
if (var == x)
{
/* If we already have a replacement, use it. Otherwise,
try to fix up this address in case it is invalid. */
replacement = find_fixup_replacement (replacements, var);
if (replacement->new)
{
*loc = replacement->new;
return;
}
*loc = replacement->new = x = fixup_stack_1 (x, insn);
/* Unless we are forcing memory to register or we changed the mode,
we can leave things the way they are if the insn is valid. */
INSN_CODE (insn) = -1;
if (! flag_force_mem && GET_MODE (x) == promoted_mode
&& recog_memoized (insn) >= 0)
return;
*loc = replacement->new = gen_reg_rtx (promoted_mode);
return;
}
/* If X contains VAR, we need to unshare it here so that we update
each occurrence separately. But all identical MEMs in one insn
must be replaced with the same rtx because of the possibility of
MATCH_DUPs. */
if (reg_mentioned_p (var, x))
{
replacement = find_fixup_replacement (replacements, x);
if (replacement->new == 0)
replacement->new = copy_most_rtx (x, var);
*loc = x = replacement->new;
}
break;
case REG:
case CC0:
case PC:
case CONST_INT:
case CONST:
case SYMBOL_REF:
case LABEL_REF:
case CONST_DOUBLE:
return;
case SIGN_EXTRACT:
case ZERO_EXTRACT:
/* Note that in some cases those types of expressions are altered
by optimize_bit_field, and do not survive to get here. */
if (XEXP (x, 0) == var
|| (GET_CODE (XEXP (x, 0)) == SUBREG
&& SUBREG_REG (XEXP (x, 0)) == var))
{
/* Get TEM as a valid MEM in the mode presently in the insn.
We don't worry about the possibility of MATCH_DUP here; it
is highly unlikely and would be tricky to handle. */
tem = XEXP (x, 0);
if (GET_CODE (tem) == SUBREG)
{
if (GET_MODE_BITSIZE (GET_MODE (tem))
> GET_MODE_BITSIZE (GET_MODE (var)))
{
replacement = find_fixup_replacement (replacements, var);
if (replacement->new == 0)
replacement->new = gen_reg_rtx (GET_MODE (var));
SUBREG_REG (tem) = replacement->new;
}
else
tem = fixup_memory_subreg (tem, insn, 0);
}
else
tem = fixup_stack_1 (tem, insn);
/* Unless we want to load from memory, get TEM into the proper mode
for an extract from memory. This can only be done if the
extract is at a constant position and length. */
if (! flag_force_mem && GET_CODE (XEXP (x, 1)) == CONST_INT
&& GET_CODE (XEXP (x, 2)) == CONST_INT
&& ! mode_dependent_address_p (XEXP (tem, 0))
&& ! MEM_VOLATILE_P (tem))
{
enum machine_mode wanted_mode = VOIDmode;
enum machine_mode is_mode = GET_MODE (tem);
int width = INTVAL (XEXP (x, 1));
int pos = INTVAL (XEXP (x, 2));
#ifdef HAVE_extzv
if (GET_CODE (x) == ZERO_EXTRACT)
wanted_mode = insn_operand_mode[(int) CODE_FOR_extzv][1];
#endif
#ifdef HAVE_extv
if (GET_CODE (x) == SIGN_EXTRACT)
wanted_mode = insn_operand_mode[(int) CODE_FOR_extv][1];
#endif
/* If we have a narrower mode, we can do something. */
if (wanted_mode != VOIDmode
&& GET_MODE_SIZE (wanted_mode) < GET_MODE_SIZE (is_mode))
{
int offset = pos / BITS_PER_UNIT;
rtx old_pos = XEXP (x, 2);
rtx newmem;
/* If the bytes and bits are counted differently, we
must adjust the offset. */
if (BYTES_BIG_ENDIAN != BITS_BIG_ENDIAN)
offset = (GET_MODE_SIZE (is_mode)
- GET_MODE_SIZE (wanted_mode) - offset);
pos %= GET_MODE_BITSIZE (wanted_mode);
newmem = gen_rtx (MEM, wanted_mode,
plus_constant (XEXP (tem, 0), offset));
RTX_UNCHANGING_P (newmem) = RTX_UNCHANGING_P (tem);
MEM_VOLATILE_P (newmem) = MEM_VOLATILE_P (tem);
MEM_IN_STRUCT_P (newmem) = MEM_IN_STRUCT_P (tem);
/* Make the change and see if the insn remains valid. */
INSN_CODE (insn) = -1;
XEXP (x, 0) = newmem;
XEXP (x, 2) = GEN_INT (pos);
if (recog_memoized (insn) >= 0)
return;
/* Otherwise, restore old position. XEXP (x, 0) will be
restored later. */
XEXP (x, 2) = old_pos;
}
}
/* If we get here, the bitfield extract insn can't accept a memory
reference. Copy the input into a register. */
tem1 = gen_reg_rtx (GET_MODE (tem));
emit_insn_before (gen_move_insn (tem1, tem), insn);
XEXP (x, 0) = tem1;
return;
}
break;
case SUBREG:
if (SUBREG_REG (x) == var)
{
/* If this is a special SUBREG made because VAR was promoted
from a wider mode, replace it with VAR and call ourself
recursively, this time saying that the object previously
had its current mode (by virtue of the SUBREG). */
if (SUBREG_PROMOTED_VAR_P (x))
{
*loc = var;
fixup_var_refs_1 (var, GET_MODE (var), loc, insn, replacements);
return;
}
/* If this SUBREG makes VAR wider, it has become a paradoxical
SUBREG with VAR in memory, but these aren't allowed at this
stage of the compilation. So load VAR into a pseudo and take
a SUBREG of that pseudo. */
if (GET_MODE_SIZE (GET_MODE (x)) > GET_MODE_SIZE (GET_MODE (var)))
{
replacement = find_fixup_replacement (replacements, var);
if (replacement->new == 0)
replacement->new = gen_reg_rtx (GET_MODE (var));
SUBREG_REG (x) = replacement->new;
return;
}
/* See if we have already found a replacement for this SUBREG.
If so, use it. Otherwise, make a MEM and see if the insn
is recognized. If not, or if we should force MEM into a register,
make a pseudo for this SUBREG. */
replacement = find_fixup_replacement (replacements, x);
if (replacement->new)
{
*loc = replacement->new;
return;
}
replacement->new = *loc = fixup_memory_subreg (x, insn, 0);
INSN_CODE (insn) = -1;
if (! flag_force_mem && recog_memoized (insn) >= 0)
return;
*loc = replacement->new = gen_reg_rtx (GET_MODE (x));
return;
}
break;
case SET:
/* First do special simplification of bit-field references. */
if (GET_CODE (SET_DEST (x)) == SIGN_EXTRACT
|| GET_CODE (SET_DEST (x)) == ZERO_EXTRACT)
optimize_bit_field (x, insn, 0);
if (GET_CODE (SET_SRC (x)) == SIGN_EXTRACT
|| GET_CODE (SET_SRC (x)) == ZERO_EXTRACT)
optimize_bit_field (x, insn, NULL_PTR);
/* For a paradoxical SUBREG inside a ZERO_EXTRACT, load the object
into a register and then store it back out. */
if (GET_CODE (SET_DEST (x)) == ZERO_EXTRACT
&& GET_CODE (XEXP (SET_DEST (x), 0)) == SUBREG
&& SUBREG_REG (XEXP (SET_DEST (x), 0)) == var
&& (GET_MODE_SIZE (GET_MODE (XEXP (SET_DEST (x), 0)))
> GET_MODE_SIZE (GET_MODE (var))))
{
replacement = find_fixup_replacement (replacements, var);
if (replacement->new == 0)
replacement->new = gen_reg_rtx (GET_MODE (var));
SUBREG_REG (XEXP (SET_DEST (x), 0)) = replacement->new;
emit_insn_after (gen_move_insn (var, replacement->new), insn);
}
/* If SET_DEST is now a paradoxical SUBREG, put the result of this
insn into a pseudo and store the low part of the pseudo into VAR. */
if (GET_CODE (SET_DEST (x)) == SUBREG
&& SUBREG_REG (SET_DEST (x)) == var
&& (GET_MODE_SIZE (GET_MODE (SET_DEST (x)))
> GET_MODE_SIZE (GET_MODE (var))))
{
SET_DEST (x) = tem = gen_reg_rtx (GET_MODE (SET_DEST (x)));
emit_insn_after (gen_move_insn (var, gen_lowpart (GET_MODE (var),
tem)),
insn);
break;
}
{
rtx dest = SET_DEST (x);
rtx src = SET_SRC (x);
rtx outerdest = dest;
while (GET_CODE (dest) == SUBREG || GET_CODE (dest) == STRICT_LOW_PART
|| GET_CODE (dest) == SIGN_EXTRACT
|| GET_CODE (dest) == ZERO_EXTRACT)
dest = XEXP (dest, 0);
if (GET_CODE (src) == SUBREG)
src = XEXP (src, 0);
/* If VAR does not appear at the top level of the SET
just scan the lower levels of the tree. */
if (src != var && dest != var)
break;
/* We will need to rerecognize this insn. */
INSN_CODE (insn) = -1;
#ifdef HAVE_insv
if (GET_CODE (outerdest) == ZERO_EXTRACT && dest == var)
{
/* Since this case will return, ensure we fixup all the
operands here. */
fixup_var_refs_1 (var, promoted_mode, &XEXP (outerdest, 1),
insn, replacements);
fixup_var_refs_1 (var, promoted_mode, &XEXP (outerdest, 2),
insn, replacements);
fixup_var_refs_1 (var, promoted_mode, &SET_SRC (x),
insn, replacements);
tem = XEXP (outerdest, 0);
/* Clean up (SUBREG:SI (MEM:mode ...) 0)
that may appear inside a ZERO_EXTRACT.
This was legitimate when the MEM was a REG. */
if (GET_CODE (tem) == SUBREG
&& SUBREG_REG (tem) == var)
tem = fixup_memory_subreg (tem, insn, 0);
else
tem = fixup_stack_1 (tem, insn);
if (GET_CODE (XEXP (outerdest, 1)) == CONST_INT
&& GET_CODE (XEXP (outerdest, 2)) == CONST_INT
&& ! mode_dependent_address_p (XEXP (tem, 0))
&& ! MEM_VOLATILE_P (tem))
{
enum machine_mode wanted_mode
= insn_operand_mode[(int) CODE_FOR_insv][0];
enum machine_mode is_mode = GET_MODE (tem);
int width = INTVAL (XEXP (outerdest, 1));
int pos = INTVAL (XEXP (outerdest, 2));
/* If we have a narrower mode, we can do something. */
if (GET_MODE_SIZE (wanted_mode) < GET_MODE_SIZE (is_mode))
{
int offset = pos / BITS_PER_UNIT;
rtx old_pos = XEXP (outerdest, 2);
rtx newmem;
if (BYTES_BIG_ENDIAN != BITS_BIG_ENDIAN)
offset = (GET_MODE_SIZE (is_mode)
- GET_MODE_SIZE (wanted_mode) - offset);
pos %= GET_MODE_BITSIZE (wanted_mode);
newmem = gen_rtx (MEM, wanted_mode,
plus_constant (XEXP (tem, 0), offset));
RTX_UNCHANGING_P (newmem) = RTX_UNCHANGING_P (tem);
MEM_VOLATILE_P (newmem) = MEM_VOLATILE_P (tem);
MEM_IN_STRUCT_P (newmem) = MEM_IN_STRUCT_P (tem);
/* Make the change and see if the insn remains valid. */
INSN_CODE (insn) = -1;
XEXP (outerdest, 0) = newmem;
XEXP (outerdest, 2) = GEN_INT (pos);
if (recog_memoized (insn) >= 0)
return;
/* Otherwise, restore old position. XEXP (x, 0) will be
restored later. */
XEXP (outerdest, 2) = old_pos;
}
}
/* If we get here, the bit-field store doesn't allow memory
or isn't located at a constant position. Load the value into
a register, do the store, and put it back into memory. */
tem1 = gen_reg_rtx (GET_MODE (tem));
emit_insn_before (gen_move_insn (tem1, tem), insn);
emit_insn_after (gen_move_insn (tem, tem1), insn);
XEXP (outerdest, 0) = tem1;
return;
}
#endif
/* STRICT_LOW_PART is a no-op on memory references
and it can cause combinations to be unrecognizable,
so eliminate it. */
if (dest == var && GET_CODE (SET_DEST (x)) == STRICT_LOW_PART)
SET_DEST (x) = XEXP (SET_DEST (x), 0);
/* A valid insn to copy VAR into or out of a register
must be left alone, to avoid an infinite loop here.
If the reference to VAR is by a subreg, fix that up,
since SUBREG is not valid for a memref.
Also fix up the address of the stack slot.
Note that we must not try to recognize the insn until
after we know that we have valid addresses and no
(subreg (mem ...) ...) constructs, since these interfere
with determining the validity of the insn. */
if ((SET_SRC (x) == var
|| (GET_CODE (SET_SRC (x)) == SUBREG
&& SUBREG_REG (SET_SRC (x)) == var))
&& (GET_CODE (SET_DEST (x)) == REG
|| (GET_CODE (SET_DEST (x)) == SUBREG
&& GET_CODE (SUBREG_REG (SET_DEST (x))) == REG))
&& GET_MODE (var) == promoted_mode
&& x == single_set (insn))
{
rtx pat;
replacement = find_fixup_replacement (replacements, SET_SRC (x));
if (replacement->new)
SET_SRC (x) = replacement->new;
else if (GET_CODE (SET_SRC (x)) == SUBREG)
SET_SRC (x) = replacement->new
= fixup_memory_subreg (SET_SRC (x), insn, 0);
else
SET_SRC (x) = replacement->new
= fixup_stack_1 (SET_SRC (x), insn);
if (recog_memoized (insn) >= 0)
return;
/* INSN is not valid, but we know that we want to
copy SET_SRC (x) to SET_DEST (x) in some way. So
we generate the move and see whether it requires more
than one insn. If it does, we emit those insns and
delete INSN. Otherwise, we an just replace the pattern
of INSN; we have already verified above that INSN has
no other function that to do X. */
pat = gen_move_insn (SET_DEST (x), SET_SRC (x));
if (GET_CODE (pat) == SEQUENCE)
{
emit_insn_after (pat, insn);
PUT_CODE (insn, NOTE);
NOTE_LINE_NUMBER (insn) = NOTE_INSN_DELETED;
NOTE_SOURCE_FILE (insn) = 0;
}
else
PATTERN (insn) = pat;
return;
}
if ((SET_DEST (x) == var
|| (GET_CODE (SET_DEST (x)) == SUBREG
&& SUBREG_REG (SET_DEST (x)) == var))
&& (GET_CODE (SET_SRC (x)) == REG
|| (GET_CODE (SET_SRC (x)) == SUBREG
&& GET_CODE (SUBREG_REG (SET_SRC (x))) == REG))
&& GET_MODE (var) == promoted_mode
&& x == single_set (insn))
{
rtx pat;
if (GET_CODE (SET_DEST (x)) == SUBREG)
SET_DEST (x) = fixup_memory_subreg (SET_DEST (x), insn, 0);
else
SET_DEST (x) = fixup_stack_1 (SET_DEST (x), insn);
if (recog_memoized (insn) >= 0)
return;
pat = gen_move_insn (SET_DEST (x), SET_SRC (x));
if (GET_CODE (pat) == SEQUENCE)
{
emit_insn_after (pat, insn);
PUT_CODE (insn, NOTE);
NOTE_LINE_NUMBER (insn) = NOTE_INSN_DELETED;
NOTE_SOURCE_FILE (insn) = 0;
}
else
PATTERN (insn) = pat;
return;
}
/* Otherwise, storing into VAR must be handled specially
by storing into a temporary and copying that into VAR
with a new insn after this one. Note that this case
will be used when storing into a promoted scalar since
the insn will now have different modes on the input
and output and hence will be invalid (except for the case
of setting it to a constant, which does not need any
change if it is valid). We generate extra code in that case,
but combine.c will eliminate it. */
if (dest == var)
{
rtx temp;
rtx fixeddest = SET_DEST (x);
/* STRICT_LOW_PART can be discarded, around a MEM. */
if (GET_CODE (fixeddest) == STRICT_LOW_PART)
fixeddest = XEXP (fixeddest, 0);
/* Convert (SUBREG (MEM)) to a MEM in a changed mode. */
if (GET_CODE (fixeddest) == SUBREG)
{
fixeddest = fixup_memory_subreg (fixeddest, insn, 0);
promoted_mode = GET_MODE (fixeddest);
}
else
fixeddest = fixup_stack_1 (fixeddest, insn);
temp = gen_reg_rtx (promoted_mode);
emit_insn_after (gen_move_insn (fixeddest,
gen_lowpart (GET_MODE (fixeddest),
temp)),
insn);
SET_DEST (x) = temp;
}
}
}
/* Nothing special about this RTX; fix its operands. */
fmt = GET_RTX_FORMAT (code);
for (i = GET_RTX_LENGTH (code) - 1; i >= 0; i--)
{
if (fmt[i] == 'e')
fixup_var_refs_1 (var, promoted_mode, &XEXP (x, i), insn, replacements);
if (fmt[i] == 'E')
{
register int j;
for (j = 0; j < XVECLEN (x, i); j++)
fixup_var_refs_1 (var, promoted_mode, &XVECEXP (x, i, j),
insn, replacements);
}
}
}
/* Given X, an rtx of the form (SUBREG:m1 (MEM:m2 addr)),
return an rtx (MEM:m1 newaddr) which is equivalent.
If any insns must be emitted to compute NEWADDR, put them before INSN.
UNCRITICAL nonzero means accept paradoxical subregs.
This is used for subregs found inside REG_NOTES. */
static rtx
fixup_memory_subreg (x, insn, uncritical)
rtx x;
rtx insn;
int uncritical;
{
int offset = SUBREG_WORD (x) * UNITS_PER_WORD;
rtx addr = XEXP (SUBREG_REG (x), 0);
enum machine_mode mode = GET_MODE (x);
rtx saved, result;
/* Paradoxical SUBREGs are usually invalid during RTL generation. */
if (GET_MODE_SIZE (mode) > GET_MODE_SIZE (GET_MODE (SUBREG_REG (x)))
&& ! uncritical)
abort ();
if (BYTES_BIG_ENDIAN)
offset += (MIN (UNITS_PER_WORD, GET_MODE_SIZE (GET_MODE (SUBREG_REG (x))))
- MIN (UNITS_PER_WORD, GET_MODE_SIZE (mode)));
addr = plus_constant (addr, offset);
if (!flag_force_addr && memory_address_p (mode, addr))
/* Shortcut if no insns need be emitted. */
return change_address (SUBREG_REG (x), mode, addr);
start_sequence ();
result = change_address (SUBREG_REG (x), mode, addr);
emit_insn_before (gen_sequence (), insn);
end_sequence ();
return result;
}
/* Do fixup_memory_subreg on all (SUBREG (MEM ...) ...) contained in X.
Replace subexpressions of X in place.
If X itself is a (SUBREG (MEM ...) ...), return the replacement expression.
Otherwise return X, with its contents possibly altered.
If any insns must be emitted to compute NEWADDR, put them before INSN.
UNCRITICAL is as in fixup_memory_subreg. */
static rtx
walk_fixup_memory_subreg (x, insn, uncritical)
register rtx x;
rtx insn;
int uncritical;
{
register enum rtx_code code;
register char *fmt;
register int i;
if (x == 0)
return 0;
code = GET_CODE (x);
if (code == SUBREG && GET_CODE (SUBREG_REG (x)) == MEM)
return fixup_memory_subreg (x, insn, uncritical);
/* Nothing special about this RTX; fix its operands. */
fmt = GET_RTX_FORMAT (code);
for (i = GET_RTX_LENGTH (code) - 1; i >= 0; i--)
{
if (fmt[i] == 'e')
XEXP (x, i) = walk_fixup_memory_subreg (XEXP (x, i), insn, uncritical);
if (fmt[i] == 'E')
{
register int j;
for (j = 0; j < XVECLEN (x, i); j++)
XVECEXP (x, i, j)
= walk_fixup_memory_subreg (XVECEXP (x, i, j), insn, uncritical);
}
}
return x;
}
/* For each memory ref within X, if it refers to a stack slot
with an out of range displacement, put the address in a temp register
(emitting new insns before INSN to load these registers)
and alter the memory ref to use that register.
Replace each such MEM rtx with a copy, to avoid clobberage. */
static rtx
fixup_stack_1 (x, insn)
rtx x;
rtx insn;
{
register int i;
register RTX_CODE code = GET_CODE (x);
register char *fmt;
if (code == MEM)
{
register rtx ad = XEXP (x, 0);
/* If we have address of a stack slot but it's not valid
(displacement is too large), compute the sum in a register. */
if (GET_CODE (ad) == PLUS
&& GET_CODE (XEXP (ad, 0)) == REG
&& ((REGNO (XEXP (ad, 0)) >= FIRST_VIRTUAL_REGISTER
&& REGNO (XEXP (ad, 0)) <= LAST_VIRTUAL_REGISTER)
|| XEXP (ad, 0) == current_function_internal_arg_pointer)
&& GET_CODE (XEXP (ad, 1)) == CONST_INT)
{
rtx temp, seq;
if (memory_address_p (GET_MODE (x), ad))
return x;
start_sequence ();
temp = copy_to_reg (ad);
seq = gen_sequence ();
end_sequence ();
emit_insn_before (seq, insn);
return change_address (x, VOIDmode, temp);
}
return x;
}
fmt = GET_RTX_FORMAT (code);
for (i = GET_RTX_LENGTH (code) - 1; i >= 0; i--)
{
if (fmt[i] == 'e')
XEXP (x, i) = fixup_stack_1 (XEXP (x, i), insn);
if (fmt[i] == 'E')
{
register int j;
for (j = 0; j < XVECLEN (x, i); j++)
XVECEXP (x, i, j) = fixup_stack_1 (XVECEXP (x, i, j), insn);
}
}
return x;
}
/* Optimization: a bit-field instruction whose field
happens to be a byte or halfword in memory
can be changed to a move instruction.
We call here when INSN is an insn to examine or store into a bit-field.
BODY is the SET-rtx to be altered.
EQUIV_MEM is the table `reg_equiv_mem' if that is available; else 0.
(Currently this is called only from function.c, and EQUIV_MEM
is always 0.) */
static void
optimize_bit_field (body, insn, equiv_mem)
rtx body;
rtx insn;
rtx *equiv_mem;
{
register rtx bitfield;
int destflag;
rtx seq = 0;
enum machine_mode mode;
if (GET_CODE (SET_DEST (body)) == SIGN_EXTRACT
|| GET_CODE (SET_DEST (body)) == ZERO_EXTRACT)
bitfield = SET_DEST (body), destflag = 1;
else
bitfield = SET_SRC (body), destflag = 0;
/* First check that the field being stored has constant size and position
and is in fact a byte or halfword suitably aligned. */
if (GET_CODE (XEXP (bitfield, 1)) == CONST_INT
&& GET_CODE (XEXP (bitfield, 2)) == CONST_INT
&& ((mode = mode_for_size (INTVAL (XEXP (bitfield, 1)), MODE_INT, 1))
!= BLKmode)
&& INTVAL (XEXP (bitfield, 2)) % INTVAL (XEXP (bitfield, 1)) == 0)
{
register rtx memref = 0;
/* Now check that the containing word is memory, not a register,
and that it is safe to change the machine mode. */
if (GET_CODE (XEXP (bitfield, 0)) == MEM)
memref = XEXP (bitfield, 0);
else if (GET_CODE (XEXP (bitfield, 0)) == REG
&& equiv_mem != 0)
memref = equiv_mem[REGNO (XEXP (bitfield, 0))];
else if (GET_CODE (XEXP (bitfield, 0)) == SUBREG
&& GET_CODE (SUBREG_REG (XEXP (bitfield, 0))) == MEM)
memref = SUBREG_REG (XEXP (bitfield, 0));
else if (GET_CODE (XEXP (bitfield, 0)) == SUBREG
&& equiv_mem != 0
&& GET_CODE (SUBREG_REG (XEXP (bitfield, 0))) == REG)
memref = equiv_mem[REGNO (SUBREG_REG (XEXP (bitfield, 0)))];
if (memref
&& ! mode_dependent_address_p (XEXP (memref, 0))
&& ! MEM_VOLATILE_P (memref))
{
/* Now adjust the address, first for any subreg'ing
that we are now getting rid of,
and then for which byte of the word is wanted. */
register int offset = INTVAL (XEXP (bitfield, 2));
rtx insns;
/* Adjust OFFSET to count bits from low-address byte. */
if (BITS_BIG_ENDIAN != BYTES_BIG_ENDIAN)
offset = (GET_MODE_BITSIZE (GET_MODE (XEXP (bitfield, 0)))
- offset - INTVAL (XEXP (bitfield, 1)));
/* Adjust OFFSET to count bytes from low-address byte. */
offset /= BITS_PER_UNIT;
if (GET_CODE (XEXP (bitfield, 0)) == SUBREG)
{
offset += SUBREG_WORD (XEXP (bitfield, 0)) * UNITS_PER_WORD;
if (BYTES_BIG_ENDIAN)
offset -= (MIN (UNITS_PER_WORD,
GET_MODE_SIZE (GET_MODE (XEXP (bitfield, 0))))
- MIN (UNITS_PER_WORD,
GET_MODE_SIZE (GET_MODE (memref))));
}
start_sequence ();
memref = change_address (memref, mode,
plus_constant (XEXP (memref, 0), offset));
insns = get_insns ();
end_sequence ();
emit_insns_before (insns, insn);
/* Store this memory reference where
we found the bit field reference. */
if (destflag)
{
validate_change (insn, &SET_DEST (body), memref, 1);
if (! CONSTANT_ADDRESS_P (SET_SRC (body)))
{
rtx src = SET_SRC (body);
while (GET_CODE (src) == SUBREG
&& SUBREG_WORD (src) == 0)
src = SUBREG_REG (src);
if (GET_MODE (src) != GET_MODE (memref))
src = gen_lowpart (GET_MODE (memref), SET_SRC (body));
validate_change (insn, &SET_SRC (body), src, 1);
}
else if (GET_MODE (SET_SRC (body)) != VOIDmode
&& GET_MODE (SET_SRC (body)) != GET_MODE (memref))
/* This shouldn't happen because anything that didn't have
one of these modes should have got converted explicitly
and then referenced through a subreg.
This is so because the original bit-field was
handled by agg_mode and so its tree structure had
the same mode that memref now has. */
abort ();
}
else
{
rtx dest = SET_DEST (body);
while (GET_CODE (dest) == SUBREG
&& SUBREG_WORD (dest) == 0
&& (GET_MODE_CLASS (GET_MODE (dest))
== GET_MODE_CLASS (GET_MODE (SUBREG_REG (dest)))))
dest = SUBREG_REG (dest);
validate_change (insn, &SET_DEST (body), dest, 1);
if (GET_MODE (dest) == GET_MODE (memref))
validate_change (insn, &SET_SRC (body), memref, 1);
else
{
/* Convert the mem ref to the destination mode. */
rtx newreg = gen_reg_rtx (GET_MODE (dest));
start_sequence ();
convert_move (newreg, memref,
GET_CODE (SET_SRC (body)) == ZERO_EXTRACT);
seq = get_insns ();
end_sequence ();
validate_change (insn, &SET_SRC (body), newreg, 1);
}
}
/* See if we can convert this extraction or insertion into
a simple move insn. We might not be able to do so if this
was, for example, part of a PARALLEL.
If we succeed, write out any needed conversions. If we fail,
it is hard to guess why we failed, so don't do anything
special; just let the optimization be suppressed. */
if (apply_change_group () && seq)
emit_insns_before (seq, insn);
}
}
}
/* These routines are responsible for converting virtual register references
to the actual hard register references once RTL generation is complete.
The following four variables are used for communication between the
routines. They contain the offsets of the virtual registers from their
respective hard registers. */
static int in_arg_offset;
static int var_offset;
static int dynamic_offset;
static int out_arg_offset;
/* In most machines, the stack pointer register is equivalent to the bottom
of the stack. */
#ifndef STACK_POINTER_OFFSET
#define STACK_POINTER_OFFSET 0
#endif
/* If not defined, pick an appropriate default for the offset of dynamically
allocated memory depending on the value of ACCUMULATE_OUTGOING_ARGS,
REG_PARM_STACK_SPACE, and OUTGOING_REG_PARM_STACK_SPACE. */
#ifndef STACK_DYNAMIC_OFFSET
#ifdef ACCUMULATE_OUTGOING_ARGS
/* The bottom of the stack points to the actual arguments. If
REG_PARM_STACK_SPACE is defined, this includes the space for the register
parameters. However, if OUTGOING_REG_PARM_STACK space is not defined,
stack space for register parameters is not pushed by the caller, but
rather part of the fixed stack areas and hence not included in
`current_function_outgoing_args_size'. Nevertheless, we must allow
for it when allocating stack dynamic objects. */
#if defined(REG_PARM_STACK_SPACE) && ! defined(OUTGOING_REG_PARM_STACK_SPACE)
#define STACK_DYNAMIC_OFFSET(FNDECL) \
(current_function_outgoing_args_size \
+ REG_PARM_STACK_SPACE (FNDECL) + (STACK_POINTER_OFFSET))
#else
#define STACK_DYNAMIC_OFFSET(FNDECL) \
(current_function_outgoing_args_size + (STACK_POINTER_OFFSET))
#endif
#else
#define STACK_DYNAMIC_OFFSET(FNDECL) STACK_POINTER_OFFSET
#endif
#endif
/* Pass through the INSNS of function FNDECL and convert virtual register
references to hard register references. */
void
instantiate_virtual_regs (fndecl, insns)
tree fndecl;
rtx insns;
{
rtx insn;
/* Compute the offsets to use for this function. */
in_arg_offset = FIRST_PARM_OFFSET (fndecl);
var_offset = STARTING_FRAME_OFFSET;
dynamic_offset = STACK_DYNAMIC_OFFSET (fndecl);
out_arg_offset = STACK_POINTER_OFFSET;
/* Scan all variables and parameters of this function. For each that is
in memory, instantiate all virtual registers if the result is a valid
address. If not, we do it later. That will handle most uses of virtual
regs on many machines. */
instantiate_decls (fndecl, 1);
/* Initialize recognition, indicating that volatile is OK. */
init_recog ();
/* Scan through all the insns, instantiating every virtual register still
present. */
for (insn = insns; insn; insn = NEXT_INSN (insn))
if (GET_CODE (insn) == INSN || GET_CODE (insn) == JUMP_INSN
|| GET_CODE (insn) == CALL_INSN)
{
instantiate_virtual_regs_1 (&PATTERN (insn), insn, 1);
instantiate_virtual_regs_1 (&REG_NOTES (insn), NULL_RTX, 0);
}
/* Now instantiate the remaining register equivalences for debugging info.
These will not be valid addresses. */
instantiate_decls (fndecl, 0);
/* Indicate that, from now on, assign_stack_local should use
frame_pointer_rtx. */
virtuals_instantiated = 1;
}
/* Scan all decls in FNDECL (both variables and parameters) and instantiate
all virtual registers in their DECL_RTL's.
If VALID_ONLY, do this only if the resulting address is still valid.
Otherwise, always do it. */
static void
instantiate_decls (fndecl, valid_only)
tree fndecl;
int valid_only;
{
tree decl;
if (DECL_SAVED_INSNS (fndecl))
/* When compiling an inline function, the obstack used for
rtl allocation is the maybepermanent_obstack. Calling
`resume_temporary_allocation' switches us back to that
obstack while we process this function's parameters. */
resume_temporary_allocation ();
/* Process all parameters of the function. */
for (decl = DECL_ARGUMENTS (fndecl); decl; decl = TREE_CHAIN (decl))
{
int size = int_size_in_bytes (TREE_TYPE (decl));
instantiate_decl (DECL_RTL (decl), size, valid_only);
/* If the parameter was promoted, then the incoming RTL mode may be
larger than the declared type size. We must use the larger of
the two sizes. */
size = MAX (GET_MODE_SIZE (GET_MODE (DECL_INCOMING_RTL (decl))), size);
instantiate_decl (DECL_INCOMING_RTL (decl), size, valid_only);
}
/* Now process all variables defined in the function or its subblocks. */
instantiate_decls_1 (DECL_INITIAL (fndecl), valid_only);
if (DECL_INLINE (fndecl) || DECL_DEFER_OUTPUT (fndecl))
{
/* Save all rtl allocated for this function by raising the
high-water mark on the maybepermanent_obstack. */
preserve_data ();
/* All further rtl allocation is now done in the current_obstack. */
rtl_in_current_obstack ();
}
}
/* Subroutine of instantiate_decls: Process all decls in the given
BLOCK node and all its subblocks. */
static void
instantiate_decls_1 (let, valid_only)
tree let;
int valid_only;
{
tree t;
for (t = BLOCK_VARS (let); t; t = TREE_CHAIN (t))
instantiate_decl (DECL_RTL (t), int_size_in_bytes (TREE_TYPE (t)),
valid_only);
/* Process all subblocks. */
for (t = BLOCK_SUBBLOCKS (let); t; t = TREE_CHAIN (t))
instantiate_decls_1 (t, valid_only);
}
/* Subroutine of the preceding procedures: Given RTL representing a
decl and the size of the object, do any instantiation required.
If VALID_ONLY is non-zero, it means that the RTL should only be
changed if the new address is valid. */
static void
instantiate_decl (x, size, valid_only)
rtx x;
int size;
int valid_only;
{
enum machine_mode mode;
rtx addr;
/* If this is not a MEM, no need to do anything. Similarly if the
address is a constant or a register that is not a virtual register. */
if (x == 0 || GET_CODE (x) != MEM)
return;
addr = XEXP (x, 0);
if (CONSTANT_P (addr)
|| (GET_CODE (addr) == REG
&& (REGNO (addr) < FIRST_VIRTUAL_REGISTER
|| REGNO (addr) > LAST_VIRTUAL_REGISTER)))
return;
/* If we should only do this if the address is valid, copy the address.
We need to do this so we can undo any changes that might make the
address invalid. This copy is unfortunate, but probably can't be
avoided. */
if (valid_only)
addr = copy_rtx (addr);
instantiate_virtual_regs_1 (&addr, NULL_RTX, 0);
if (valid_only)
{
/* Now verify that the resulting address is valid for every integer or
floating-point mode up to and including SIZE bytes long. We do this
since the object might be accessed in any mode and frame addresses
are shared. */
for (mode = GET_CLASS_NARROWEST_MODE (MODE_INT);
mode != VOIDmode && GET_MODE_SIZE (mode) <= size;
mode = GET_MODE_WIDER_MODE (mode))
if (! memory_address_p (mode, addr))
return;
for (mode = GET_CLASS_NARROWEST_MODE (MODE_FLOAT);
mode != VOIDmode && GET_MODE_SIZE (mode) <= size;
mode = GET_MODE_WIDER_MODE (mode))
if (! memory_address_p (mode, addr))
return;
}
/* Put back the address now that we have updated it and we either know
it is valid or we don't care whether it is valid. */
XEXP (x, 0) = addr;
}
/* Given a pointer to a piece of rtx and an optional pointer to the
containing object, instantiate any virtual registers present in it.
If EXTRA_INSNS, we always do the replacement and generate
any extra insns before OBJECT. If it zero, we do nothing if replacement
is not valid.
Return 1 if we either had nothing to do or if we were able to do the
needed replacement. Return 0 otherwise; we only return zero if
EXTRA_INSNS is zero.
We first try some simple transformations to avoid the creation of extra
pseudos. */
static int
instantiate_virtual_regs_1 (loc, object, extra_insns)
rtx *loc;
rtx object;
int extra_insns;
{
rtx x;
RTX_CODE code;
rtx new = 0;
int offset;
rtx temp;
rtx seq;
int i, j;
char *fmt;
/* Re-start here to avoid recursion in common cases. */
restart:
x = *loc;
if (x == 0)
return 1;
code = GET_CODE (x);
/* Check for some special cases. */
switch (code)
{
case CONST_INT:
case CONST_DOUBLE:
case CONST:
case SYMBOL_REF:
case CODE_LABEL:
case PC:
case CC0:
case ASM_INPUT:
case ADDR_VEC:
case ADDR_DIFF_VEC:
case RETURN:
return 1;
case SET:
/* We are allowed to set the virtual registers. This means that
that the actual register should receive the source minus the
appropriate offset. This is used, for example, in the handling
of non-local gotos. */
if (SET_DEST (x) == virtual_incoming_args_rtx)
new = arg_pointer_rtx, offset = - in_arg_offset;
else if (SET_DEST (x) == virtual_stack_vars_rtx)
new = frame_pointer_rtx, offset = - var_offset;
else if (SET_DEST (x) == virtual_stack_dynamic_rtx)
new = stack_pointer_rtx, offset = - dynamic_offset;
else if (SET_DEST (x) == virtual_outgoing_args_rtx)
new = stack_pointer_rtx, offset = - out_arg_offset;
if (new)
{
/* The only valid sources here are PLUS or REG. Just do
the simplest possible thing to handle them. */
if (GET_CODE (SET_SRC (x)) != REG
&& GET_CODE (SET_SRC (x)) != PLUS)
abort ();
start_sequence ();
if (GET_CODE (SET_SRC (x)) != REG)
temp = force_operand (SET_SRC (x), NULL_RTX);
else
temp = SET_SRC (x);
temp = force_operand (plus_constant (temp, offset), NULL_RTX);
seq = get_insns ();
end_sequence ();
emit_insns_before (seq, object);
SET_DEST (x) = new;
if (!validate_change (object, &SET_SRC (x), temp, 0)
|| ! extra_insns)
abort ();
return 1;
}
instantiate_virtual_regs_1 (&SET_DEST (x), object, extra_insns);
loc = &SET_SRC (x);
goto restart;
case PLUS:
/* Handle special case of virtual register plus constant. */
if (CONSTANT_P (XEXP (x, 1)))
{
rtx old, new_offset;
/* Check for (plus (plus VIRT foo) (const_int)) first. */
if (GET_CODE (XEXP (x, 0)) == PLUS)
{
rtx inner = XEXP (XEXP (x, 0), 0);
if (inner == virtual_incoming_args_rtx)
new = arg_pointer_rtx, offset = in_arg_offset;
else if (inner == virtual_stack_vars_rtx)
new = frame_pointer_rtx, offset = var_offset;
else if (inner == virtual_stack_dynamic_rtx)
new = stack_pointer_rtx, offset = dynamic_offset;
else if (inner == virtual_outgoing_args_rtx)
new = stack_pointer_rtx, offset = out_arg_offset;
else
{
loc = &XEXP (x, 0);
goto restart;
}
instantiate_virtual_regs_1 (&XEXP (XEXP (x, 0), 1), object,
extra_insns);
new = gen_rtx (PLUS, Pmode, new, XEXP (XEXP (x, 0), 1));
}
else if (XEXP (x, 0) == virtual_incoming_args_rtx)
new = arg_pointer_rtx, offset = in_arg_offset;
else if (XEXP (x, 0) == virtual_stack_vars_rtx)
new = frame_pointer_rtx, offset = var_offset;
else if (XEXP (x, 0) == virtual_stack_dynamic_rtx)
new = stack_pointer_rtx, offset = dynamic_offset;
else if (XEXP (x, 0) == virtual_outgoing_args_rtx)
new = stack_pointer_rtx, offset = out_arg_offset;
else
{
/* We know the second operand is a constant. Unless the
first operand is a REG (which has been already checked),
it needs to be checked. */
if (GET_CODE (XEXP (x, 0)) != REG)
{
loc = &XEXP (x, 0);
goto restart;
}
return 1;
}
new_offset = plus_constant (XEXP (x, 1), offset);
/* If the new constant is zero, try to replace the sum with just
the register. */
if (new_offset == const0_rtx
&& validate_change (object, loc, new, 0))
return 1;
/* Next try to replace the register and new offset.
There are two changes to validate here and we can't assume that
in the case of old offset equals new just changing the register
will yield a valid insn. In the interests of a little efficiency,
however, we only call validate change once (we don't queue up the
changes and then call apply_change_group). */
old = XEXP (x, 0);
if (offset == 0
? ! validate_change (object, &XEXP (x, 0), new, 0)
: (XEXP (x, 0) = new,
! validate_change (object, &XEXP (x, 1), new_offset, 0)))
{
if (! extra_insns)
{
XEXP (x, 0) = old;
return 0;
}
/* Otherwise copy the new constant into a register and replace
constant with that register. */
temp = gen_reg_rtx (Pmode);
XEXP (x, 0) = new;
if (validate_change (object, &XEXP (x, 1), temp, 0))
emit_insn_before (gen_move_insn (temp, new_offset), object);
else
{
/* If that didn't work, replace this expression with a
register containing the sum. */
XEXP (x, 0) = old;
new = gen_rtx (PLUS, Pmode, new, new_offset);
start_sequence ();
temp = force_operand (new, NULL_RTX);
seq = get_insns ();
end_sequence ();
emit_insns_before (seq, object);
if (! validate_change (object, loc, temp, 0)
&& ! validate_replace_rtx (x, temp, object))
abort ();
}
}
return 1;
}
/* Fall through to generic two-operand expression case. */
case EXPR_LIST:
case CALL:
case COMPARE:
case MINUS:
case MULT:
case DIV: case UDIV:
case MOD: case UMOD:
case AND: case IOR: case XOR:
case ROTATERT: case ROTATE:
case ASHIFTRT: case LSHIFTRT: case ASHIFT:
case NE: case EQ:
case GE: case GT: case GEU: case GTU:
case LE: case LT: case LEU: case LTU:
if (XEXP (x, 1) && ! CONSTANT_P (XEXP (x, 1)))
instantiate_virtual_regs_1 (&XEXP (x, 1), object, extra_insns);
loc = &XEXP (x, 0);
goto restart;
case MEM:
/* Most cases of MEM that convert to valid addresses have already been
handled by our scan of decls. The only special handling we
need here is to make a copy of the rtx to ensure it isn't being
shared if we have to change it to a pseudo.
If the rtx is a simple reference to an address via a virtual register,
it can potentially be shared. In such cases, first try to make it
a valid address, which can also be shared. Otherwise, copy it and
proceed normally.
First check for common cases that need no processing. These are
usually due to instantiation already being done on a previous instance
of a shared rtx. */
temp = XEXP (x, 0);
if (CONSTANT_ADDRESS_P (temp)
#if FRAME_POINTER_REGNUM != ARG_POINTER_REGNUM
|| temp == arg_pointer_rtx
#endif
#if HARD_FRAME_POINTER_REGNUM != FRAME_POINTER_REGNUM
|| temp == hard_frame_pointer_rtx
#endif
|| temp == frame_pointer_rtx)
return 1;
if (GET_CODE (temp) == PLUS
&& CONSTANT_ADDRESS_P (XEXP (temp, 1))
&& (XEXP (temp, 0) == frame_pointer_rtx
#if HARD_FRAME_POINTER_REGNUM != FRAME_POINTER_REGNUM
|| XEXP (temp, 0) == hard_frame_pointer_rtx
#endif
#if FRAME_POINTER_REGNUM != ARG_POINTER_REGNUM
|| XEXP (temp, 0) == arg_pointer_rtx
#endif
))
return 1;
if (temp == virtual_stack_vars_rtx
|| temp == virtual_incoming_args_rtx
|| (GET_CODE (temp) == PLUS
&& CONSTANT_ADDRESS_P (XEXP (temp, 1))
&& (XEXP (temp, 0) == virtual_stack_vars_rtx
|| XEXP (temp, 0) == virtual_incoming_args_rtx)))
{
/* This MEM may be shared. If the substitution can be done without
the need to generate new pseudos, we want to do it in place
so all copies of the shared rtx benefit. The call below will
only make substitutions if the resulting address is still
valid.
Note that we cannot pass X as the object in the recursive call
since the insn being processed may not allow all valid
addresses. However, if we were not passed on object, we can
only modify X without copying it if X will have a valid
address.
??? Also note that this can still lose if OBJECT is an insn that
has less restrictions on an address that some other insn.
In that case, we will modify the shared address. This case
doesn't seem very likely, though. One case where this could
happen is in the case of a USE or CLOBBER reference, but we
take care of that below. */
if (instantiate_virtual_regs_1 (&XEXP (x, 0),
object ? object : x, 0))
return 1;
/* Otherwise make a copy and process that copy. We copy the entire
RTL expression since it might be a PLUS which could also be
shared. */
*loc = x = copy_rtx (x);
}
/* Fall through to generic unary operation case. */
case SUBREG:
case STRICT_LOW_PART:
case NEG: case NOT:
case PRE_DEC: case PRE_INC: case POST_DEC: case POST_INC:
case SIGN_EXTEND: case ZERO_EXTEND:
case TRUNCATE: case FLOAT_EXTEND: case FLOAT_TRUNCATE:
case FLOAT: case FIX:
case UNSIGNED_FIX: case UNSIGNED_FLOAT:
case ABS:
case SQRT:
case FFS:
/* These case either have just one operand or we know that we need not
check the rest of the operands. */
loc = &XEXP (x, 0);
goto restart;
case USE:
case CLOBBER:
/* If the operand is a MEM, see if the change is a valid MEM. If not,
go ahead and make the invalid one, but do it to a copy. For a REG,
just make the recursive call, since there's no chance of a problem. */
if ((GET_CODE (XEXP (x, 0)) == MEM
&& instantiate_virtual_regs_1 (&XEXP (XEXP (x, 0), 0), XEXP (x, 0),
0))
|| (GET_CODE (XEXP (x, 0)) == REG
&& instantiate_virtual_regs_1 (&XEXP (x, 0), object, 0)))
return 1;
XEXP (x, 0) = copy_rtx (XEXP (x, 0));
loc = &XEXP (x, 0);
goto restart;
case REG:
/* Try to replace with a PLUS. If that doesn't work, compute the sum
in front of this insn and substitute the temporary. */
if (x == virtual_incoming_args_rtx)
new = arg_pointer_rtx, offset = in_arg_offset;
else if (x == virtual_stack_vars_rtx)
new = frame_pointer_rtx, offset = var_offset;
else if (x == virtual_stack_dynamic_rtx)
new = stack_pointer_rtx, offset = dynamic_offset;
else if (x == virtual_outgoing_args_rtx)
new = stack_pointer_rtx, offset = out_arg_offset;
if (new)
{
temp = plus_constant (new, offset);
if (!validate_change (object, loc, temp, 0))
{
if (! extra_insns)
return 0;
start_sequence ();
temp = force_operand (temp, NULL_RTX);
seq = get_insns ();
end_sequence ();
emit_insns_before (seq, object);
if (! validate_change (object, loc, temp, 0)
&& ! validate_replace_rtx (x, temp, object))
abort ();
}
}
return 1;
}
/* Scan all subexpressions. */
fmt = GET_RTX_FORMAT (code);
for (i = 0; i < GET_RTX_LENGTH (code); i++, fmt++)
if (*fmt == 'e')
{
if (!instantiate_virtual_regs_1 (&XEXP (x, i), object, extra_insns))
return 0;
}
else if (*fmt == 'E')
for (j = 0; j < XVECLEN (x, i); j++)
if (! instantiate_virtual_regs_1 (&XVECEXP (x, i, j), object,
extra_insns))
return 0;
return 1;
}
/* Optimization: assuming this function does not receive nonlocal gotos,
delete the handlers for such, as well as the insns to establish
and disestablish them. */
static void
delete_handlers ()
{
rtx insn;
for (insn = get_insns (); insn; insn = NEXT_INSN (insn))
{
/* Delete the handler by turning off the flag that would
prevent jump_optimize from deleting it.
Also permit deletion of the nonlocal labels themselves
if nothing local refers to them. */
if (GET_CODE (insn) == CODE_LABEL)
{
tree t, last_t;
LABEL_PRESERVE_P (insn) = 0;
/* Remove it from the nonlocal_label list, to avoid confusing
flow. */
for (t = nonlocal_labels, last_t = 0; t;
last_t = t, t = TREE_CHAIN (t))
if (DECL_RTL (TREE_VALUE (t)) == insn)
break;
if (t)
{
if (! last_t)
nonlocal_labels = TREE_CHAIN (nonlocal_labels);
else
TREE_CHAIN (last_t) = TREE_CHAIN (t);
}
}
if (GET_CODE (insn) == INSN
&& ((nonlocal_goto_handler_slot != 0
&& reg_mentioned_p (nonlocal_goto_handler_slot, PATTERN (insn)))
|| (nonlocal_goto_stack_level != 0
&& reg_mentioned_p (nonlocal_goto_stack_level,
PATTERN (insn)))))
delete_insn (insn);
}
}
/* Return a list (chain of EXPR_LIST nodes) for the nonlocal labels
of the current function. */
rtx
nonlocal_label_rtx_list ()
{
tree t;
rtx x = 0;
for (t = nonlocal_labels; t; t = TREE_CHAIN (t))
x = gen_rtx (EXPR_LIST, VOIDmode, label_rtx (TREE_VALUE (t)), x);
return x;
}
/* Output a USE for any register use in RTL.
This is used with -noreg to mark the extent of lifespan
of any registers used in a user-visible variable's DECL_RTL. */
void
use_variable (rtl)
rtx rtl;
{
if (GET_CODE (rtl) == REG)
/* This is a register variable. */
emit_insn (gen_rtx (USE, VOIDmode, rtl));
else if (GET_CODE (rtl) == MEM
&& GET_CODE (XEXP (rtl, 0)) == REG
&& (REGNO (XEXP (rtl, 0)) < FIRST_VIRTUAL_REGISTER
|| REGNO (XEXP (rtl, 0)) > LAST_VIRTUAL_REGISTER)
&& XEXP (rtl, 0) != current_function_internal_arg_pointer)
/* This is a variable-sized structure. */
emit_insn (gen_rtx (USE, VOIDmode, XEXP (rtl, 0)));
}
/* Like use_variable except that it outputs the USEs after INSN
instead of at the end of the insn-chain. */
void
use_variable_after (rtl, insn)
rtx rtl, insn;
{
if (GET_CODE (rtl) == REG)
/* This is a register variable. */
emit_insn_after (gen_rtx (USE, VOIDmode, rtl), insn);
else if (GET_CODE (rtl) == MEM
&& GET_CODE (XEXP (rtl, 0)) == REG
&& (REGNO (XEXP (rtl, 0)) < FIRST_VIRTUAL_REGISTER
|| REGNO (XEXP (rtl, 0)) > LAST_VIRTUAL_REGISTER)
&& XEXP (rtl, 0) != current_function_internal_arg_pointer)
/* This is a variable-sized structure. */
emit_insn_after (gen_rtx (USE, VOIDmode, XEXP (rtl, 0)), insn);
}
int
max_parm_reg_num ()
{
return max_parm_reg;
}
/* Return the first insn following those generated by `assign_parms'. */
rtx
get_first_nonparm_insn ()
{
if (last_parm_insn)
return NEXT_INSN (last_parm_insn);
return get_insns ();
}
/* Return the first NOTE_INSN_BLOCK_BEG note in the function.
Crash if there is none. */
rtx
get_first_block_beg ()
{
register rtx searcher;
register rtx insn = get_first_nonparm_insn ();
for (searcher = insn; searcher; searcher = NEXT_INSN (searcher))
if (GET_CODE (searcher) == NOTE
&& NOTE_LINE_NUMBER (searcher) == NOTE_INSN_BLOCK_BEG)
return searcher;
abort (); /* Invalid call to this function. (See comments above.) */
return NULL_RTX;
}
/* Return 1 if EXP is an aggregate type (or a value with aggregate type).
This means a type for which function calls must pass an address to the
function or get an address back from the function.
EXP may be a type node or an expression (whose type is tested). */
int
aggregate_value_p (exp)
tree exp;
{
int i, regno, nregs;
rtx reg;
tree type;
if (TREE_CODE_CLASS (TREE_CODE (exp)) == 't')
type = exp;
else
type = TREE_TYPE (exp);
if (RETURN_IN_MEMORY (type))
return 1;
/* Types that are TREE_ADDRESSABLE must be contructed in memory,
and thus can't be returned in registers. */
if (TREE_ADDRESSABLE (type))
return 1;
if (flag_pcc_struct_return && AGGREGATE_TYPE_P (type))
return 1;
/* Make sure we have suitable call-clobbered regs to return
the value in; if not, we must return it in memory. */
reg = hard_function_value (type, 0);
/* If we have something other than a REG (e.g. a PARALLEL), then assume
it is OK. */
if (GET_CODE (reg) != REG)
return 0;
regno = REGNO (reg);
nregs = HARD_REGNO_NREGS (regno, TYPE_MODE (type));
for (i = 0; i < nregs; i++)
if (! call_used_regs[regno + i])
return 1;
return 0;
}
/* Assign RTL expressions to the function's parameters.
This may involve copying them into registers and using
those registers as the RTL for them.
If SECOND_TIME is non-zero it means that this function is being
called a second time. This is done by integrate.c when a function's
compilation is deferred. We need to come back here in case the
FUNCTION_ARG macro computes items needed for the rest of the compilation
(such as changing which registers are fixed or caller-saved). But suppress
writing any insns or setting DECL_RTL of anything in this case. */
void
assign_parms (fndecl, second_time)
tree fndecl;
int second_time;
{
register tree parm;
register rtx entry_parm = 0;
register rtx stack_parm = 0;
CUMULATIVE_ARGS args_so_far;
enum machine_mode promoted_mode, passed_mode;
enum machine_mode nominal_mode, promoted_nominal_mode;
int unsignedp;
/* Total space needed so far for args on the stack,
given as a constant and a tree-expression. */
struct args_size stack_args_size;
tree fntype = TREE_TYPE (fndecl);
tree fnargs = DECL_ARGUMENTS (fndecl);
/* This is used for the arg pointer when referring to stack args. */
rtx internal_arg_pointer;
/* This is a dummy PARM_DECL that we used for the function result if
the function returns a structure. */
tree function_result_decl = 0;
int nparmregs = list_length (fnargs) + LAST_VIRTUAL_REGISTER + 1;
int varargs_setup = 0;
rtx conversion_insns = 0;
/* Nonzero if the last arg is named `__builtin_va_alist',
which is used on some machines for old-fashioned non-ANSI varargs.h;
this should be stuck onto the stack as if it had arrived there. */
int hide_last_arg
= (current_function_varargs
&& fnargs
&& (parm = tree_last (fnargs)) != 0
&& DECL_NAME (parm)
&& (! strcmp (IDENTIFIER_POINTER (DECL_NAME (parm)),
"__builtin_va_alist")));
/* Nonzero if function takes extra anonymous args.
This means the last named arg must be on the stack
right before the anonymous ones. */
int stdarg
= (TYPE_ARG_TYPES (fntype) != 0
&& (TREE_VALUE (tree_last (TYPE_ARG_TYPES (fntype)))
!= void_type_node));
current_function_stdarg = stdarg;
/* If the reg that the virtual arg pointer will be translated into is
not a fixed reg or is the stack pointer, make a copy of the virtual
arg pointer, and address parms via the copy. The frame pointer is
considered fixed even though it is not marked as such.
The second time through, simply use ap to avoid generating rtx. */
if ((ARG_POINTER_REGNUM == STACK_POINTER_REGNUM
|| ! (fixed_regs[ARG_POINTER_REGNUM]
|| ARG_POINTER_REGNUM == FRAME_POINTER_REGNUM))
&& ! second_time)
internal_arg_pointer = copy_to_reg (virtual_incoming_args_rtx);
else
internal_arg_pointer = virtual_incoming_args_rtx;
current_function_internal_arg_pointer = internal_arg_pointer;
stack_args_size.constant = 0;
stack_args_size.var = 0;
/* If struct value address is treated as the first argument, make it so. */
if (aggregate_value_p (DECL_RESULT (fndecl))
&& ! current_function_returns_pcc_struct
&& struct_value_incoming_rtx == 0)
{
tree type = build_pointer_type (TREE_TYPE (fntype));
function_result_decl = build_decl (PARM_DECL, NULL_TREE, type);
DECL_ARG_TYPE (function_result_decl) = type;
TREE_CHAIN (function_result_decl) = fnargs;
fnargs = function_result_decl;
}
parm_reg_stack_loc = (rtx *) oballoc (nparmregs * sizeof (rtx));
bzero ((char *) parm_reg_stack_loc, nparmregs * sizeof (rtx));
#ifdef INIT_CUMULATIVE_INCOMING_ARGS
INIT_CUMULATIVE_INCOMING_ARGS (args_so_far, fntype, NULL_RTX);
#else
INIT_CUMULATIVE_ARGS (args_so_far, fntype, NULL_RTX, 0);
#endif
/* We haven't yet found an argument that we must push and pretend the
caller did. */
current_function_pretend_args_size = 0;
for (parm = fnargs; parm; parm = TREE_CHAIN (parm))
{
int aggregate = AGGREGATE_TYPE_P (TREE_TYPE (parm));
struct args_size stack_offset;
struct args_size arg_size;
int passed_pointer = 0;
int did_conversion = 0;
tree passed_type = DECL_ARG_TYPE (parm);
tree nominal_type = TREE_TYPE (parm);
/* Set LAST_NAMED if this is last named arg before some
anonymous args. */
int last_named = ((TREE_CHAIN (parm) == 0
|| DECL_NAME (TREE_CHAIN (parm)) == 0)
&& (stdarg || current_function_varargs));
/* Set NAMED_ARG if this arg should be treated as a named arg. For
most machines, if this is a varargs/stdarg function, then we treat
the last named arg as if it were anonymous too. */
#ifdef STRICT_ARGUMENT_NAMING
int named_arg = 1;
#else
int named_arg = ! last_named;
#endif
if (TREE_TYPE (parm) == error_mark_node
/* This can happen after weird syntax errors
or if an enum type is defined among the parms. */
|| TREE_CODE (parm) != PARM_DECL
|| passed_type == NULL)
{
DECL_INCOMING_RTL (parm) = DECL_RTL (parm) = gen_rtx (MEM, BLKmode,
const0_rtx);
TREE_USED (parm) = 1;
continue;
}
/* For varargs.h function, save info about regs and stack space
used by the individual args, not including the va_alist arg. */
if (hide_last_arg && last_named)
current_function_args_info = args_so_far;
/* Find mode of arg as it is passed, and mode of arg
as it should be during execution of this function. */
passed_mode = TYPE_MODE (passed_type);
nominal_mode = TYPE_MODE (nominal_type);
/* If the parm's mode is VOID, its value doesn't matter,
and avoid the usual things like emit_move_insn that could crash. */
if (nominal_mode == VOIDmode)
{
DECL_INCOMING_RTL (parm) = DECL_RTL (parm) = const0_rtx;
continue;
}
/* If the parm is to be passed as a transparent union, use the
type of the first field for the tests below. We have already
verified that the modes are the same. */
if (DECL_TRANSPARENT_UNION (parm)
|| TYPE_TRANSPARENT_UNION (passed_type))
passed_type = TREE_TYPE (TYPE_FIELDS (passed_type));
/* See if this arg was passed by invisible reference. It is if
it is an object whose size depends on the contents of the
object itself or if the machine requires these objects be passed
that way. */
if ((TREE_CODE (TYPE_SIZE (passed_type)) != INTEGER_CST
&& contains_placeholder_p (TYPE_SIZE (passed_type)))
|| TREE_ADDRESSABLE (passed_type)
#ifdef FUNCTION_ARG_PASS_BY_REFERENCE
|| FUNCTION_ARG_PASS_BY_REFERENCE (args_so_far, passed_mode,
passed_type, named_arg)
#endif
)
{
passed_type = nominal_type = build_pointer_type (passed_type);
passed_pointer = 1;
passed_mode = nominal_mode = Pmode;
}
promoted_mode = passed_mode;
#ifdef PROMOTE_FUNCTION_ARGS
/* Compute the mode in which the arg is actually extended to. */
promoted_mode = promote_mode (passed_type, promoted_mode, &unsignedp, 1);
#endif
/* Let machine desc say which reg (if any) the parm arrives in.
0 means it arrives on the stack. */
#ifdef FUNCTION_INCOMING_ARG
entry_parm = FUNCTION_INCOMING_ARG (args_so_far, promoted_mode,
passed_type, named_arg);
#else
entry_parm = FUNCTION_ARG (args_so_far, promoted_mode,
passed_type, named_arg);
#endif
if (entry_parm == 0)
promoted_mode = passed_mode;
#ifdef SETUP_INCOMING_VARARGS
/* If this is the last named parameter, do any required setup for
varargs or stdargs. We need to know about the case of this being an
addressable type, in which case we skip the registers it
would have arrived in.
For stdargs, LAST_NAMED will be set for two parameters, the one that
is actually the last named, and the dummy parameter. We only
want to do this action once.
Also, indicate when RTL generation is to be suppressed. */
if (last_named && !varargs_setup)
{
SETUP_INCOMING_VARARGS (args_so_far, promoted_mode, passed_type,
current_function_pretend_args_size,
second_time);
varargs_setup = 1;
}
#endif
/* Determine parm's home in the stack,
in case it arrives in the stack or we should pretend it did.
Compute the stack position and rtx where the argument arrives
and its size.
There is one complexity here: If this was a parameter that would
have been passed in registers, but wasn't only because it is
__builtin_va_alist, we want locate_and_pad_parm to treat it as if
it came in a register so that REG_PARM_STACK_SPACE isn't skipped.
In this case, we call FUNCTION_ARG with NAMED set to 1 instead of
0 as it was the previous time. */
locate_and_pad_parm (promoted_mode, passed_type,
#ifdef STACK_PARMS_IN_REG_PARM_AREA
1,
#else
#ifdef FUNCTION_INCOMING_ARG
FUNCTION_INCOMING_ARG (args_so_far, promoted_mode,
passed_type,
(named_arg
|| varargs_setup)) != 0,
#else
FUNCTION_ARG (args_so_far, promoted_mode,
passed_type,
named_arg || varargs_setup) != 0,
#endif
#endif
fndecl, &stack_args_size, &stack_offset, &arg_size);
if (! second_time)
{
rtx offset_rtx = ARGS_SIZE_RTX (stack_offset);
if (offset_rtx == const0_rtx)
stack_parm = gen_rtx (MEM, promoted_mode, internal_arg_pointer);
else
stack_parm = gen_rtx (MEM, promoted_mode,
gen_rtx (PLUS, Pmode,
internal_arg_pointer, offset_rtx));
/* If this is a memory ref that contains aggregate components,
mark it as such for cse and loop optimize. Likewise if it
is readonly. */
MEM_IN_STRUCT_P (stack_parm) = aggregate;
RTX_UNCHANGING_P (stack_parm) = TREE_READONLY (parm);
}
/* If this parameter was passed both in registers and in the stack,
use the copy on the stack. */
if (MUST_PASS_IN_STACK (promoted_mode, passed_type))
entry_parm = 0;
#ifdef FUNCTION_ARG_PARTIAL_NREGS
/* If this parm was passed part in regs and part in memory,
pretend it arrived entirely in memory
by pushing the register-part onto the stack.
In the special case of a DImode or DFmode that is split,
we could put it together in a pseudoreg directly,
but for now that's not worth bothering with. */
if (entry_parm)
{
int nregs = FUNCTION_ARG_PARTIAL_NREGS (args_so_far, promoted_mode,
passed_type, named_arg);
if (nregs > 0)
{
current_function_pretend_args_size
= (((nregs * UNITS_PER_WORD) + (PARM_BOUNDARY / BITS_PER_UNIT) - 1)
/ (PARM_BOUNDARY / BITS_PER_UNIT)
* (PARM_BOUNDARY / BITS_PER_UNIT));
if (! second_time)
{
/* Handle calls that pass values in multiple non-contiguous
locations. The Irix 6 ABI has examples of this. */
if (GET_CODE (entry_parm) == PARALLEL)
emit_group_store (validize_mem (stack_parm),
entry_parm);
else
move_block_from_reg (REGNO (entry_parm),
validize_mem (stack_parm), nregs,
int_size_in_bytes (TREE_TYPE (parm)));
}
entry_parm = stack_parm;
}
}
#endif
/* If we didn't decide this parm came in a register,
by default it came on the stack. */
if (entry_parm == 0)
entry_parm = stack_parm;
/* Record permanently how this parm was passed. */
if (! second_time)
DECL_INCOMING_RTL (parm) = entry_parm;
/* If there is actually space on the stack for this parm,
count it in stack_args_size; otherwise set stack_parm to 0
to indicate there is no preallocated stack slot for the parm. */
if (entry_parm == stack_parm
#if defined (REG_PARM_STACK_SPACE) && ! defined (MAYBE_REG_PARM_STACK_SPACE)
/* On some machines, even if a parm value arrives in a register
there is still an (uninitialized) stack slot allocated for it.
??? When MAYBE_REG_PARM_STACK_SPACE is defined, we can't tell
whether this parameter already has a stack slot allocated,
because an arg block exists only if current_function_args_size
is larger than some threshold, and we haven't calculated that
yet. So, for now, we just assume that stack slots never exist
in this case. */
|| REG_PARM_STACK_SPACE (fndecl) > 0
#endif
)
{
stack_args_size.constant += arg_size.constant;
if (arg_size.var)
ADD_PARM_SIZE (stack_args_size, arg_size.var);
}
else
/* No stack slot was pushed for this parm. */
stack_parm = 0;
/* Update info on where next arg arrives in registers. */
FUNCTION_ARG_ADVANCE (args_so_far, promoted_mode,
passed_type, named_arg);
/* If this is our second time through, we are done with this parm. */
if (second_time)
continue;
/* If we can't trust the parm stack slot to be aligned enough
for its ultimate type, don't use that slot after entry.
We'll make another stack slot, if we need one. */
{
int thisparm_boundary
= FUNCTION_ARG_BOUNDARY (promoted_mode, passed_type);
if (GET_MODE_ALIGNMENT (nominal_mode) > thisparm_boundary)
stack_parm = 0;
}
/* If parm was passed in memory, and we need to convert it on entry,
don't store it back in that same slot. */
if (entry_parm != 0
&& nominal_mode != BLKmode && nominal_mode != passed_mode)
stack_parm = 0;
#if 0
/* Now adjust STACK_PARM to the mode and precise location
where this parameter should live during execution,
if we discover that it must live in the stack during execution.
To make debuggers happier on big-endian machines, we store
the value in the last bytes of the space available. */
if (nominal_mode != BLKmode && nominal_mode != passed_mode
&& stack_parm != 0)
{
rtx offset_rtx;
if (BYTES_BIG_ENDIAN
&& GET_MODE_SIZE (nominal_mode) < UNITS_PER_WORD)
stack_offset.constant += (GET_MODE_SIZE (passed_mode)
- GET_MODE_SIZE (nominal_mode));
offset_rtx = ARGS_SIZE_RTX (stack_offset);
if (offset_rtx == const0_rtx)
stack_parm = gen_rtx (MEM, nominal_mode, internal_arg_pointer);
else
stack_parm = gen_rtx (MEM, nominal_mode,
gen_rtx (PLUS, Pmode,
if (flag_check_memory_usage)
{
push_to_sequence (conversion_insns);
emit_library_call (chkr_set_right_libfunc, 1, VOIDmode, 3,
XEXP (stack_parm, 0), ptr_mode,
GEN_INT (int_size_in_bytes
(TREE_TYPE (parm))),
TYPE_MODE (sizetype),
GEN_INT (MEMORY_USE_RW), QImode);
conversion_insns = get_insns ();
end_sequence ();
}
internal_arg_pointer, offset_rtx));
/* If this is a memory ref that contains aggregate components,
mark it as such for cse and loop optimize. */
MEM_IN_STRUCT_P (stack_parm) = aggregate;
}
#endif /* 0 */
#ifdef STACK_REGS
/* We need this "use" info, because the gcc-register->stack-register
converter in reg-stack.c needs to know which registers are active
at the start of the function call. The actual parameter loading
instructions are not always available then anymore, since they might
have been optimised away. */
if (GET_CODE (entry_parm) == REG && !(hide_last_arg && last_named))
emit_insn (gen_rtx (USE, GET_MODE (entry_parm), entry_parm));
#endif
/* ENTRY_PARM is an RTX for the parameter as it arrives,
in the mode in which it arrives.
STACK_PARM is an RTX for a stack slot where the parameter can live
during the function (in case we want to put it there).
STACK_PARM is 0 if no stack slot was pushed for it.
Now output code if necessary to convert ENTRY_PARM to
the type in which this function declares it,
and store that result in an appropriate place,
which may be a pseudo reg, may be STACK_PARM,
or may be a local stack slot if STACK_PARM is 0.
Set DECL_RTL to that place. */
if (nominal_mode == BLKmode || GET_CODE (entry_parm) == PARALLEL)
{
/* If a BLKmode arrives in registers, copy it to a stack slot.
Handle calls that pass values in multiple non-contiguous
locations. The Irix 6 ABI has examples of this. */
if (GET_CODE (entry_parm) == REG
|| GET_CODE (entry_parm) == PARALLEL)
{
int size_stored
= CEIL_ROUND (int_size_in_bytes (TREE_TYPE (parm)),
UNITS_PER_WORD);
/* Note that we will be storing an integral number of words.
So we have to be careful to ensure that we allocate an
integral number of words. We do this below in the
assign_stack_local if space was not allocated in the argument
list. If it was, this will not work if PARM_BOUNDARY is not
a multiple of BITS_PER_WORD. It isn't clear how to fix this
if it becomes a problem. */
if (stack_parm == 0)
{
stack_parm
= assign_stack_local (GET_MODE (entry_parm),
size_stored, 0);
/* If this is a memory ref that contains aggregate
components, mark it as such for cse and loop optimize. */
MEM_IN_STRUCT_P (stack_parm) = aggregate;
}
else if (PARM_BOUNDARY % BITS_PER_WORD != 0)
abort ();
if (TREE_READONLY (parm))
RTX_UNCHANGING_P (stack_parm) = 1;
/* Handle calls that pass values in multiple non-contiguous
locations. The Irix 6 ABI has examples of this. */
if (GET_CODE (entry_parm) == PARALLEL)
emit_group_store (validize_mem (stack_parm), entry_parm);
else
move_block_from_reg (REGNO (entry_parm),
validize_mem (stack_parm),
size_stored / UNITS_PER_WORD,
int_size_in_bytes (TREE_TYPE (parm)));
}
DECL_RTL (parm) = stack_parm;
}
else if (! ((obey_regdecls && ! DECL_REGISTER (parm)
&& ! DECL_INLINE (fndecl))
/* layout_decl may set this. */
|| TREE_ADDRESSABLE (parm)
|| TREE_SIDE_EFFECTS (parm)
/* If -ffloat-store specified, don't put explicit
float variables into registers. */
|| (flag_float_store
&& TREE_CODE (TREE_TYPE (parm)) == REAL_TYPE))
/* Always assign pseudo to structure return or item passed
by invisible reference. */
|| passed_pointer || parm == function_result_decl)
{
/* Store the parm in a pseudoregister during the function, but we
may need to do it in a wider mode. */
register rtx parmreg;
int regno, regnoi, regnor;
unsignedp = TREE_UNSIGNED (TREE_TYPE (parm));
promoted_nominal_mode
= promote_mode (TREE_TYPE (parm), nominal_mode, &unsignedp, 0);
parmreg = gen_reg_rtx (promoted_nominal_mode);
mark_user_reg (parmreg);
/* If this was an item that we received a pointer to, set DECL_RTL
appropriately. */
if (passed_pointer)
{
DECL_RTL (parm)
= gen_rtx (MEM, TYPE_MODE (TREE_TYPE (passed_type)), parmreg);
MEM_IN_STRUCT_P (DECL_RTL (parm)) = aggregate;
}
else
DECL_RTL (parm) = parmreg;
/* Copy the value into the register. */
if (nominal_mode != passed_mode
|| promoted_nominal_mode != promoted_mode)
{
/* ENTRY_PARM has been converted to PROMOTED_MODE, its
mode, by the caller. We now have to convert it to
NOMINAL_MODE, if different. However, PARMREG may be in
a diffent mode than NOMINAL_MODE if it is being stored
promoted.
If ENTRY_PARM is a hard register, it might be in a register
not valid for operating in its mode (e.g., an odd-numbered
register for a DFmode). In that case, moves are the only
thing valid, so we can't do a convert from there. This
occurs when the calling sequence allow such misaligned
usages.
In addition, the conversion may involve a call, which could
clobber parameters which haven't been copied to pseudo
registers yet. Therefore, we must first copy the parm to
a pseudo reg here, and save the conversion until after all
parameters have been moved. */
rtx tempreg = gen_reg_rtx (GET_MODE (entry_parm));
emit_move_insn (tempreg, validize_mem (entry_parm));
push_to_sequence (conversion_insns);
tempreg = convert_to_mode (nominal_mode, tempreg, unsignedp);
expand_assignment (parm,
make_tree (nominal_type, tempreg), 0, 0);
conversion_insns = get_insns ();
did_conversion = 1;
end_sequence ();
}
else
emit_move_insn (parmreg, validize_mem (entry_parm));
/* If we were passed a pointer but the actual value
can safely live in a register, put it in one. */
if (passed_pointer && TYPE_MODE (TREE_TYPE (parm)) != BLKmode
&& ! ((obey_regdecls && ! DECL_REGISTER (parm)
&& ! DECL_INLINE (fndecl))
/* layout_decl may set this. */
|| TREE_ADDRESSABLE (parm)
|| TREE_SIDE_EFFECTS (parm)
/* If -ffloat-store specified, don't put explicit
float variables into registers. */
|| (flag_float_store
&& TREE_CODE (TREE_TYPE (parm)) == REAL_TYPE)))
{
/* We can't use nominal_mode, because it will have been set to
Pmode above. We must use the actual mode of the parm. */
parmreg = gen_reg_rtx (TYPE_MODE (TREE_TYPE (parm)));
mark_user_reg (parmreg);
emit_move_insn (parmreg, DECL_RTL (parm));
DECL_RTL (parm) = parmreg;
/* STACK_PARM is the pointer, not the parm, and PARMREG is
now the parm. */
stack_parm = 0;
}
#ifdef FUNCTION_ARG_CALLEE_COPIES
/* If we are passed an arg by reference and it is our responsibility
to make a copy, do it now.
PASSED_TYPE and PASSED mode now refer to the pointer, not the
original argument, so we must recreate them in the call to
FUNCTION_ARG_CALLEE_COPIES. */
/* ??? Later add code to handle the case that if the argument isn't
modified, don't do the copy. */
else if (passed_pointer
&& FUNCTION_ARG_CALLEE_COPIES (args_so_far,
TYPE_MODE (DECL_ARG_TYPE (parm)),
DECL_ARG_TYPE (parm),
named_arg)
&& ! TREE_ADDRESSABLE (DECL_ARG_TYPE (parm)))
{
rtx copy;
tree type = DECL_ARG_TYPE (parm);
/* This sequence may involve a library call perhaps clobbering
registers that haven't been copied to pseudos yet. */
push_to_sequence (conversion_insns);
if (TYPE_SIZE (type) == 0
|| TREE_CODE (TYPE_SIZE (type)) != INTEGER_CST)
/* This is a variable sized object. */
copy = gen_rtx (MEM, BLKmode,
allocate_dynamic_stack_space
(expr_size (parm), NULL_RTX,
TYPE_ALIGN (type)));
else
copy = assign_stack_temp (TYPE_MODE (type),
int_size_in_bytes (type), 1);
MEM_IN_STRUCT_P (copy) = AGGREGATE_TYPE_P (type);
store_expr (parm, copy, 0);
emit_move_insn (parmreg, XEXP (copy, 0));
if (flag_check_memory_usage)
emit_library_call (chkr_set_right_libfunc, 1, VOIDmode, 3,
XEXP (copy, 0), ptr_mode,
GEN_INT (int_size_in_bytes (type)),
TYPE_MODE (sizetype),
GEN_INT (MEMORY_USE_RW), QImode);
conversion_insns = get_insns ();
did_conversion = 1;
end_sequence ();
}
#endif /* FUNCTION_ARG_CALLEE_COPIES */
/* In any case, record the parm's desired stack location
in case we later discover it must live in the stack.
If it is a COMPLEX value, store the stack location for both
halves. */
if (GET_CODE (parmreg) == CONCAT)
regno = MAX (REGNO (XEXP (parmreg, 0)), REGNO (XEXP (parmreg, 1)));
else
regno = REGNO (parmreg);
if (regno >= nparmregs)
{
rtx *new;
int old_nparmregs = nparmregs;
nparmregs = regno + 5;
new = (rtx *) oballoc (nparmregs * sizeof (rtx));
bcopy ((char *) parm_reg_stack_loc, (char *) new,
old_nparmregs * sizeof (rtx));
bzero ((char *) (new + old_nparmregs),
(nparmregs - old_nparmregs) * sizeof (rtx));
parm_reg_stack_loc = new;
}
if (GET_CODE (parmreg) == CONCAT)
{
enum machine_mode submode = GET_MODE (XEXP (parmreg, 0));
regnor = REGNO (gen_realpart (submode, parmreg));
regnoi = REGNO (gen_imagpart (submode, parmreg));
if (stack_parm != 0)
{
parm_reg_stack_loc[regnor]
= gen_realpart (submode, stack_parm);
parm_reg_stack_loc[regnoi]
= gen_imagpart (submode, stack_parm);
}
else
{
parm_reg_stack_loc[regnor] = 0;
parm_reg_stack_loc[regnoi] = 0;
}
}
else
parm_reg_stack_loc[REGNO (parmreg)] = stack_parm;
/* Mark the register as eliminable if we did no conversion
and it was copied from memory at a fixed offset,
and the arg pointer was not copied to a pseudo-reg.
If the arg pointer is a pseudo reg or the offset formed
an invalid address, such memory-equivalences
as we make here would screw up life analysis for it. */
if (nominal_mode == passed_mode
&& ! did_conversion
&& stack_parm != 0
&& GET_CODE (stack_parm) == MEM
&& stack_offset.var == 0
&& reg_mentioned_p (virtual_incoming_args_rtx,
XEXP (stack_parm, 0)))
{
rtx linsn = get_last_insn ();
rtx sinsn, set;
/* Mark complex types separately. */
if (GET_CODE (parmreg) == CONCAT)
/* Scan backwards for the set of the real and
imaginary parts. */
for (sinsn = linsn; sinsn != 0;
sinsn = prev_nonnote_insn (sinsn))
{
set = single_set (sinsn);
if (set != 0
&& SET_DEST (set) == regno_reg_rtx [regnoi])
REG_NOTES (sinsn)
= gen_rtx (EXPR_LIST, REG_EQUIV,
parm_reg_stack_loc[regnoi],
REG_NOTES (sinsn));
else if (set != 0
&& SET_DEST (set) == regno_reg_rtx [regnor])
REG_NOTES (sinsn)
= gen_rtx (EXPR_LIST, REG_EQUIV,
parm_reg_stack_loc[regnor],
REG_NOTES (sinsn));
}
else if ((set = single_set (linsn)) != 0
&& SET_DEST (set) == parmreg)
REG_NOTES (linsn)
= gen_rtx (EXPR_LIST, REG_EQUIV,
stack_parm, REG_NOTES (linsn));
}
/* For pointer data type, suggest pointer register. */
if (TREE_CODE (TREE_TYPE (parm)) == POINTER_TYPE)
mark_reg_pointer (parmreg,
(TYPE_ALIGN (TREE_TYPE (TREE_TYPE (parm)))
/ BITS_PER_UNIT));
}
else
{
/* Value must be stored in the stack slot STACK_PARM
during function execution. */
if (promoted_mode != nominal_mode)
{
/* Conversion is required. */
rtx tempreg = gen_reg_rtx (GET_MODE (entry_parm));
emit_move_insn (tempreg, validize_mem (entry_parm));
push_to_sequence (conversion_insns);
entry_parm = convert_to_mode (nominal_mode, tempreg,
TREE_UNSIGNED (TREE_TYPE (parm)));
if (stack_parm)
{
/* ??? This may need a big-endian conversion on sparc64. */
stack_parm = change_address (stack_parm, nominal_mode,
NULL_RTX);
}
conversion_insns = get_insns ();
did_conversion = 1;
end_sequence ();
}
if (entry_parm != stack_parm)
{
if (stack_parm == 0)
{
stack_parm
= assign_stack_local (GET_MODE (entry_parm),
GET_MODE_SIZE (GET_MODE (entry_parm)), 0);
/* If this is a memory ref that contains aggregate components,
mark it as such for cse and loop optimize. */
MEM_IN_STRUCT_P (stack_parm) = aggregate;
}
if (promoted_mode != nominal_mode)
{
push_to_sequence (conversion_insns);
emit_move_insn (validize_mem (stack_parm),
validize_mem (entry_parm));
conversion_insns = get_insns ();
end_sequence ();
}
else
emit_move_insn (validize_mem (stack_parm),
validize_mem (entry_parm));
}
if (flag_check_memory_usage)
{
push_to_sequence (conversion_insns);
emit_library_call (chkr_set_right_libfunc, 1, VOIDmode, 3,
XEXP (stack_parm, 0), ptr_mode,
GEN_INT (GET_MODE_SIZE (GET_MODE
(entry_parm))),
TYPE_MODE (sizetype),
GEN_INT (MEMORY_USE_RW), QImode);
conversion_insns = get_insns ();
end_sequence ();
}
DECL_RTL (parm) = stack_parm;
}
/* If this "parameter" was the place where we are receiving the
function's incoming structure pointer, set up the result. */
if (parm == function_result_decl)
{
tree result = DECL_RESULT (fndecl);
tree restype = TREE_TYPE (result);
DECL_RTL (result)
= gen_rtx (MEM, DECL_MODE (result), DECL_RTL (parm));
MEM_IN_STRUCT_P (DECL_RTL (result)) = AGGREGATE_TYPE_P (restype);
}
if (TREE_THIS_VOLATILE (parm))
MEM_VOLATILE_P (DECL_RTL (parm)) = 1;
if (TREE_READONLY (parm))
RTX_UNCHANGING_P (DECL_RTL (parm)) = 1;
}
/* Output all parameter conversion instructions (possibly including calls)
now that all parameters have been copied out of hard registers. */
emit_insns (conversion_insns);
max_parm_reg = max_reg_num ();
last_parm_insn = get_last_insn ();
current_function_args_size = stack_args_size.constant;
/* Adjust function incoming argument size for alignment and
minimum length. */
#ifdef REG_PARM_STACK_SPACE
#ifndef MAYBE_REG_PARM_STACK_SPACE
current_function_args_size = MAX (current_function_args_size,
REG_PARM_STACK_SPACE (fndecl));
#endif
#endif
#ifdef STACK_BOUNDARY
#define STACK_BYTES (STACK_BOUNDARY / BITS_PER_UNIT)
current_function_args_size
= ((current_function_args_size + STACK_BYTES - 1)
/ STACK_BYTES) * STACK_BYTES;
#endif
#ifdef ARGS_GROW_DOWNWARD
current_function_arg_offset_rtx
= (stack_args_size.var == 0 ? GEN_INT (-stack_args_size.constant)
: expand_expr (size_binop (MINUS_EXPR, stack_args_size.var,
size_int (-stack_args_size.constant)),
NULL_RTX, VOIDmode, EXPAND_MEMORY_USE_BAD));
#else
current_function_arg_offset_rtx = ARGS_SIZE_RTX (stack_args_size);
#endif
/* See how many bytes, if any, of its args a function should try to pop
on return. */
current_function_pops_args = RETURN_POPS_ARGS (fndecl, TREE_TYPE (fndecl),
current_function_args_size);
/* For stdarg.h function, save info about
regs and stack space used by the named args. */
if (!hide_last_arg)
current_function_args_info = args_so_far;
/* Set the rtx used for the function return value. Put this in its
own variable so any optimizers that need this information don't have
to include tree.h. Do this here so it gets done when an inlined
function gets output. */
current_function_return_rtx = DECL_RTL (DECL_RESULT (fndecl));
}
/* Indicate whether REGNO is an incoming argument to the current function
that was promoted to a wider mode. If so, return the RTX for the
register (to get its mode). PMODE and PUNSIGNEDP are set to the mode
that REGNO is promoted from and whether the promotion was signed or
unsigned. */
#ifdef PROMOTE_FUNCTION_ARGS
rtx
promoted_input_arg (regno, pmode, punsignedp)
int regno;
enum machine_mode *pmode;
int *punsignedp;
{
tree arg;
for (arg = DECL_ARGUMENTS (current_function_decl); arg;
arg = TREE_CHAIN (arg))
if (GET_CODE (DECL_INCOMING_RTL (arg)) == REG
&& REGNO (DECL_INCOMING_RTL (arg)) == regno
&& TYPE_MODE (DECL_ARG_TYPE (arg)) == TYPE_MODE (TREE_TYPE (arg)))
{
enum machine_mode mode = TYPE_MODE (TREE_TYPE (arg));
int unsignedp = TREE_UNSIGNED (TREE_TYPE (arg));
mode = promote_mode (TREE_TYPE (arg), mode, &unsignedp, 1);
if (mode == GET_MODE (DECL_INCOMING_RTL (arg))
&& mode != DECL_MODE (arg))
{
*pmode = DECL_MODE (arg);
*punsignedp = unsignedp;
return DECL_INCOMING_RTL (arg);
}
}
return 0;
}
#endif
/* Compute the size and offset from the start of the stacked arguments for a
parm passed in mode PASSED_MODE and with type TYPE.
INITIAL_OFFSET_PTR points to the current offset into the stacked
arguments.
The starting offset and size for this parm are returned in *OFFSET_PTR
and *ARG_SIZE_PTR, respectively.
IN_REGS is non-zero if the argument will be passed in registers. It will
never be set if REG_PARM_STACK_SPACE is not defined.
FNDECL is the function in which the argument was defined.
There are two types of rounding that are done. The first, controlled by
FUNCTION_ARG_BOUNDARY, forces the offset from the start of the argument
list to be aligned to the specific boundary (in bits). This rounding
affects the initial and starting offsets, but not the argument size.
The second, controlled by FUNCTION_ARG_PADDING and PARM_BOUNDARY,
optionally rounds the size of the parm to PARM_BOUNDARY. The
initial offset is not affected by this rounding, while the size always
is and the starting offset may be. */
/* offset_ptr will be negative for ARGS_GROW_DOWNWARD case;
initial_offset_ptr is positive because locate_and_pad_parm's
callers pass in the total size of args so far as
initial_offset_ptr. arg_size_ptr is always positive.*/
void
locate_and_pad_parm (passed_mode, type, in_regs, fndecl,
initial_offset_ptr, offset_ptr, arg_size_ptr)
enum machine_mode passed_mode;
tree type;
int in_regs;
tree fndecl;
struct args_size *initial_offset_ptr;
struct args_size *offset_ptr;
struct args_size *arg_size_ptr;
{
tree sizetree
= type ? size_in_bytes (type) : size_int (GET_MODE_SIZE (passed_mode));
enum direction where_pad = FUNCTION_ARG_PADDING (passed_mode, type);
int boundary = FUNCTION_ARG_BOUNDARY (passed_mode, type);
int boundary_in_bytes = boundary / BITS_PER_UNIT;
int reg_parm_stack_space = 0;
#ifdef REG_PARM_STACK_SPACE
/* If we have found a stack parm before we reach the end of the
area reserved for registers, skip that area. */
if (! in_regs)
{
#ifdef MAYBE_REG_PARM_STACK_SPACE
reg_parm_stack_space = MAYBE_REG_PARM_STACK_SPACE;
#else
reg_parm_stack_space = REG_PARM_STACK_SPACE (fndecl);
#endif
if (reg_parm_stack_space > 0)
{
if (initial_offset_ptr->var)
{
initial_offset_ptr->var
= size_binop (MAX_EXPR, ARGS_SIZE_TREE (*initial_offset_ptr),
size_int (reg_parm_stack_space));
initial_offset_ptr->constant = 0;
}
else if (initial_offset_ptr->constant < reg_parm_stack_space)
initial_offset_ptr->constant = reg_parm_stack_space;
}
}
#endif /* REG_PARM_STACK_SPACE */
arg_size_ptr->var = 0;
arg_size_ptr->constant = 0;
#ifdef ARGS_GROW_DOWNWARD
if (initial_offset_ptr->var)
{
offset_ptr->constant = 0;
offset_ptr->var = size_binop (MINUS_EXPR, integer_zero_node,
initial_offset_ptr->var);
}
else
{
offset_ptr->constant = - initial_offset_ptr->constant;
offset_ptr->var = 0;
}
if (where_pad != none
&& (TREE_CODE (sizetree) != INTEGER_CST
|| ((TREE_INT_CST_LOW (sizetree) * BITS_PER_UNIT) % PARM_BOUNDARY)))
sizetree = round_up (sizetree, PARM_BOUNDARY / BITS_PER_UNIT);
SUB_PARM_SIZE (*offset_ptr, sizetree);
if (where_pad != downward)
pad_to_arg_alignment (offset_ptr, boundary);
if (initial_offset_ptr->var)
{
arg_size_ptr->var = size_binop (MINUS_EXPR,
size_binop (MINUS_EXPR,
integer_zero_node,
initial_offset_ptr->var),
offset_ptr->var);
}
else
{
arg_size_ptr->constant = (- initial_offset_ptr->constant
- offset_ptr->constant);
}
#else /* !ARGS_GROW_DOWNWARD */
pad_to_arg_alignment (initial_offset_ptr, boundary);
*offset_ptr = *initial_offset_ptr;
#ifdef PUSH_ROUNDING
if (passed_mode != BLKmode)
sizetree = size_int (PUSH_ROUNDING (TREE_INT_CST_LOW (sizetree)));
#endif
/* Pad_below needs the pre-rounded size to know how much to pad below
so this must be done before rounding up. */
if (where_pad == downward
/* However, BLKmode args passed in regs have their padding done elsewhere.
The stack slot must be able to hold the entire register. */
&& !(in_regs && passed_mode == BLKmode))
pad_below (offset_ptr, passed_mode, sizetree);
if (where_pad != none
&& (TREE_CODE (sizetree) != INTEGER_CST
|| ((TREE_INT_CST_LOW (sizetree) * BITS_PER_UNIT) % PARM_BOUNDARY)))
sizetree = round_up (sizetree, PARM_BOUNDARY / BITS_PER_UNIT);
ADD_PARM_SIZE (*arg_size_ptr, sizetree);
#endif /* ARGS_GROW_DOWNWARD */
}
/* Round the stack offset in *OFFSET_PTR up to a multiple of BOUNDARY.
BOUNDARY is measured in bits, but must be a multiple of a storage unit. */
static void
pad_to_arg_alignment (offset_ptr, boundary)
struct args_size *offset_ptr;
int boundary;
{
int boundary_in_bytes = boundary / BITS_PER_UNIT;
if (boundary > BITS_PER_UNIT)
{
if (offset_ptr->var)
{
offset_ptr->var =
#ifdef ARGS_GROW_DOWNWARD
round_down
#else
round_up
#endif
(ARGS_SIZE_TREE (*offset_ptr),
boundary / BITS_PER_UNIT);
offset_ptr->constant = 0; /*?*/
}
else
offset_ptr->constant =
#ifdef ARGS_GROW_DOWNWARD
FLOOR_ROUND (offset_ptr->constant, boundary_in_bytes);
#else
CEIL_ROUND (offset_ptr->constant, boundary_in_bytes);
#endif
}
}
static void
pad_below (offset_ptr, passed_mode, sizetree)
struct args_size *offset_ptr;
enum machine_mode passed_mode;
tree sizetree;
{
if (passed_mode != BLKmode)
{
if (GET_MODE_BITSIZE (passed_mode) % PARM_BOUNDARY)
offset_ptr->constant
+= (((GET_MODE_BITSIZE (passed_mode) + PARM_BOUNDARY - 1)
/ PARM_BOUNDARY * PARM_BOUNDARY / BITS_PER_UNIT)
- GET_MODE_SIZE (passed_mode));
}
else
{
if (TREE_CODE (sizetree) != INTEGER_CST
|| (TREE_INT_CST_LOW (sizetree) * BITS_PER_UNIT) % PARM_BOUNDARY)
{
/* Round the size up to multiple of PARM_BOUNDARY bits. */
tree s2 = round_up (sizetree, PARM_BOUNDARY / BITS_PER_UNIT);
/* Add it in. */
ADD_PARM_SIZE (*offset_ptr, s2);
SUB_PARM_SIZE (*offset_ptr, sizetree);
}
}
}
static tree
round_down (value, divisor)
tree value;
int divisor;
{
return size_binop (MULT_EXPR,
size_binop (FLOOR_DIV_EXPR, value, size_int (divisor)),
size_int (divisor));
}
/* Walk the tree of blocks describing the binding levels within a function
and warn about uninitialized variables.
This is done after calling flow_analysis and before global_alloc
clobbers the pseudo-regs to hard regs. */
void
uninitialized_vars_warning (block)
tree block;
{
register tree decl, sub;
for (decl = BLOCK_VARS (block); decl; decl = TREE_CHAIN (decl))
{
if (TREE_CODE (decl) == VAR_DECL
/* These warnings are unreliable for and aggregates
because assigning the fields one by one can fail to convince
flow.c that the entire aggregate was initialized.
Unions are troublesome because members may be shorter. */
&& ! AGGREGATE_TYPE_P (TREE_TYPE (decl))
&& DECL_RTL (decl) != 0
&& GET_CODE (DECL_RTL (decl)) == REG
&& regno_uninitialized (REGNO (DECL_RTL (decl))))
warning_with_decl (decl,
"`%s' might be used uninitialized in this function");
if (TREE_CODE (decl) == VAR_DECL
&& DECL_RTL (decl) != 0
&& GET_CODE (DECL_RTL (decl)) == REG
&& regno_clobbered_at_setjmp (REGNO (DECL_RTL (decl))))
warning_with_decl (decl,
"variable `%s' might be clobbered by `longjmp' or `vfork'");
}
for (sub = BLOCK_SUBBLOCKS (block); sub; sub = TREE_CHAIN (sub))
uninitialized_vars_warning (sub);
}
/* Do the appropriate part of uninitialized_vars_warning
but for arguments instead of local variables. */
void
setjmp_args_warning ()
{
register tree decl;
for (decl = DECL_ARGUMENTS (current_function_decl);
decl; decl = TREE_CHAIN (decl))
if (DECL_RTL (decl) != 0
&& GET_CODE (DECL_RTL (decl)) == REG
&& regno_clobbered_at_setjmp (REGNO (DECL_RTL (decl))))
warning_with_decl (decl, "argument `%s' might be clobbered by `longjmp' or `vfork'");
}
/* If this function call setjmp, put all vars into the stack
unless they were declared `register'. */
void
setjmp_protect (block)
tree block;
{
register tree decl, sub;
for (decl = BLOCK_VARS (block); decl; decl = TREE_CHAIN (decl))
if ((TREE_CODE (decl) == VAR_DECL
|| TREE_CODE (decl) == PARM_DECL)
&& DECL_RTL (decl) != 0
&& GET_CODE (DECL_RTL (decl)) == REG
/* If this variable came from an inline function, it must be
that it's life doesn't overlap the setjmp. If there was a
setjmp in the function, it would already be in memory. We
must exclude such variable because their DECL_RTL might be
set to strange things such as virtual_stack_vars_rtx. */
&& ! DECL_FROM_INLINE (decl)
&& (
#ifdef NON_SAVING_SETJMP
/* If longjmp doesn't restore the registers,
don't put anything in them. */
NON_SAVING_SETJMP
||
#endif
! DECL_REGISTER (decl)))
put_var_into_stack (decl);
for (sub = BLOCK_SUBBLOCKS (block); sub; sub = TREE_CHAIN (sub))
setjmp_protect (sub);
}
/* Like the previous function, but for args instead of local variables. */
void
setjmp_protect_args ()
{
register tree decl, sub;
for (decl = DECL_ARGUMENTS (current_function_decl);
decl; decl = TREE_CHAIN (decl))
if ((TREE_CODE (decl) == VAR_DECL
|| TREE_CODE (decl) == PARM_DECL)
&& DECL_RTL (decl) != 0
&& GET_CODE (DECL_RTL (decl)) == REG
&& (
/* If longjmp doesn't restore the registers,
don't put anything in them. */
#ifdef NON_SAVING_SETJMP
NON_SAVING_SETJMP
||
#endif
! DECL_REGISTER (decl)))
put_var_into_stack (decl);
}
/* Return the context-pointer register corresponding to DECL,
or 0 if it does not need one. */
rtx
lookup_static_chain (decl)
tree decl;
{
tree context = decl_function_context (decl);
tree link;
if (context == 0
|| (TREE_CODE (decl) == FUNCTION_DECL && DECL_NO_STATIC_CHAIN (decl)))
return 0;
/* We treat inline_function_decl as an alias for the current function
because that is the inline function whose vars, types, etc.
are being merged into the current function.
See expand_inline_function. */
if (context == current_function_decl || context == inline_function_decl)
return virtual_stack_vars_rtx;
for (link = context_display; link; link = TREE_CHAIN (link))
if (TREE_PURPOSE (link) == context)
return RTL_EXPR_RTL (TREE_VALUE (link));
abort ();
}
/* Convert a stack slot address ADDR for variable VAR
(from a containing function)
into an address valid in this function (using a static chain). */
rtx
fix_lexical_addr (addr, var)
rtx addr;
tree var;
{
rtx basereg;
int displacement;
tree context = decl_function_context (var);
struct function *fp;
rtx base = 0;
/* If this is the present function, we need not do anything. */
if (context == current_function_decl || context == inline_function_decl)
return addr;
for (fp = outer_function_chain; fp; fp = fp->next)
if (fp->decl == context)
break;
if (fp == 0)
abort ();
/* Decode given address as base reg plus displacement. */
if (GET_CODE (addr) == REG)
basereg = addr, displacement = 0;
else if (GET_CODE (addr) == PLUS && GET_CODE (XEXP (addr, 1)) == CONST_INT)
basereg = XEXP (addr, 0), displacement = INTVAL (XEXP (addr, 1));
else
abort ();
/* We accept vars reached via the containing function's
incoming arg pointer and via its stack variables pointer. */
if (basereg == fp->internal_arg_pointer)
{
/* If reached via arg pointer, get the arg pointer value
out of that function's stack frame.
There are two cases: If a separate ap is needed, allocate a
slot in the outer function for it and dereference it that way.
This is correct even if the real ap is actually a pseudo.
Otherwise, just adjust the offset from the frame pointer to
compensate. */
#ifdef NEED_SEPARATE_AP
rtx addr;
if (fp->arg_pointer_save_area == 0)
fp->arg_pointer_save_area
= assign_outer_stack_local (Pmode, GET_MODE_SIZE (Pmode), 0, fp);
addr = fix_lexical_addr (XEXP (fp->arg_pointer_save_area, 0), var);
addr = memory_address (Pmode, addr);
base = copy_to_reg (gen_rtx (MEM, Pmode, addr));
#else
displacement += (FIRST_PARM_OFFSET (context) - STARTING_FRAME_OFFSET);
base = lookup_static_chain (var);
#endif
}
else if (basereg == virtual_stack_vars_rtx)
{
/* This is the same code as lookup_static_chain, duplicated here to
avoid an extra call to decl_function_context. */
tree link;
for (link = context_display; link; link = TREE_CHAIN (link))
if (TREE_PURPOSE (link) == context)
{
base = RTL_EXPR_RTL (TREE_VALUE (link));
break;
}
}
if (base == 0)
abort ();
/* Use same offset, relative to appropriate static chain or argument
pointer. */
return plus_constant (base, displacement);
}
/* Return the address of the trampoline for entering nested fn FUNCTION.
If necessary, allocate a trampoline (in the stack frame)
and emit rtl to initialize its contents (at entry to this function). */
rtx
trampoline_address (function)
tree function;
{
tree link;
tree rtlexp;
rtx tramp;
struct function *fp;
tree fn_context;
/* Find an existing trampoline and return it. */
for (link = trampoline_list; link; link = TREE_CHAIN (link))
if (TREE_PURPOSE (link) == function)
return
round_trampoline_addr (XEXP (RTL_EXPR_RTL (TREE_VALUE (link)), 0));
for (fp = outer_function_chain; fp; fp = fp->next)
for (link = fp->trampoline_list; link; link = TREE_CHAIN (link))
if (TREE_PURPOSE (link) == function)
{
tramp = fix_lexical_addr (XEXP (RTL_EXPR_RTL (TREE_VALUE (link)), 0),
function);
return round_trampoline_addr (tramp);
}
/* None exists; we must make one. */
/* Find the `struct function' for the function containing FUNCTION. */
fp = 0;
fn_context = decl_function_context (function);
if (fn_context != current_function_decl
&& fn_context != inline_function_decl)
for (fp = outer_function_chain; fp; fp = fp->next)
if (fp->decl == fn_context)
break;
/* Allocate run-time space for this trampoline
(usually in the defining function's stack frame). */
#ifdef ALLOCATE_TRAMPOLINE
tramp = ALLOCATE_TRAMPOLINE (fp);
#else
/* If rounding needed, allocate extra space
to ensure we have TRAMPOLINE_SIZE bytes left after rounding up. */
#ifdef TRAMPOLINE_ALIGNMENT
#define TRAMPOLINE_REAL_SIZE \
(TRAMPOLINE_SIZE + (TRAMPOLINE_ALIGNMENT / BITS_PER_UNIT) - 1)
#else
#define TRAMPOLINE_REAL_SIZE (TRAMPOLINE_SIZE)
#endif
if (fp != 0)
tramp = assign_outer_stack_local (BLKmode, TRAMPOLINE_REAL_SIZE, 0, fp);
else
tramp = assign_stack_local (BLKmode, TRAMPOLINE_REAL_SIZE, 0);
#endif
/* Record the trampoline for reuse and note it for later initialization
by expand_function_end. */
if (fp != 0)
{
push_obstacks (fp->function_maybepermanent_obstack,
fp->function_maybepermanent_obstack);
rtlexp = make_node (RTL_EXPR);
RTL_EXPR_RTL (rtlexp) = tramp;
fp->trampoline_list = tree_cons (function, rtlexp, fp->trampoline_list);
pop_obstacks ();
}
else
{
/* Make the RTL_EXPR node temporary, not momentary, so that the
trampoline_list doesn't become garbage. */
int momentary = suspend_momentary ();
rtlexp = make_node (RTL_EXPR);
resume_momentary (momentary);
RTL_EXPR_RTL (rtlexp) = tramp;
trampoline_list = tree_cons (function, rtlexp, trampoline_list);
}
tramp = fix_lexical_addr (XEXP (tramp, 0), function);
return round_trampoline_addr (tramp);
}
/* Given a trampoline address,
round it to multiple of TRAMPOLINE_ALIGNMENT. */
static rtx
round_trampoline_addr (tramp)
rtx tramp;
{
#ifdef TRAMPOLINE_ALIGNMENT
/* Round address up to desired boundary. */
rtx temp = gen_reg_rtx (Pmode);
temp = expand_binop (Pmode, add_optab, tramp,
GEN_INT (TRAMPOLINE_ALIGNMENT / BITS_PER_UNIT - 1),
temp, 0, OPTAB_LIB_WIDEN);
tramp = expand_binop (Pmode, and_optab, temp,
GEN_INT (- TRAMPOLINE_ALIGNMENT / BITS_PER_UNIT),
temp, 0, OPTAB_LIB_WIDEN);
#endif
return tramp;
}
/* The functions identify_blocks and reorder_blocks provide a way to
reorder the tree of BLOCK nodes, for optimizers that reshuffle or
duplicate portions of the RTL code. Call identify_blocks before
changing the RTL, and call reorder_blocks after. */
/* Put all this function's BLOCK nodes including those that are chained
onto the first block into a vector, and return it.
Also store in each NOTE for the beginning or end of a block
the index of that block in the vector.
The arguments are BLOCK, the chain of top-level blocks of the function,
and INSNS, the insn chain of the function. */
tree *
identify_blocks (block, insns)
tree block;
rtx insns;
{
int n_blocks;
tree *block_vector;
int *block_stack;
int depth = 0;
int next_block_number = 1;
int current_block_number = 1;
rtx insn;
if (block == 0)
return 0;
n_blocks = all_blocks (block, 0);
block_vector = (tree *) xmalloc (n_blocks * sizeof (tree));
block_stack = (int *) alloca (n_blocks * sizeof (int));
all_blocks (block, block_vector);
for (insn = insns; insn; insn = NEXT_INSN (insn))
if (GET_CODE (insn) == NOTE)
{
if (NOTE_LINE_NUMBER (insn) == NOTE_INSN_BLOCK_BEG)
{
block_stack[depth++] = current_block_number;
current_block_number = next_block_number;
NOTE_BLOCK_NUMBER (insn) = next_block_number++;
}
if (NOTE_LINE_NUMBER (insn) == NOTE_INSN_BLOCK_END)
{
current_block_number = block_stack[--depth];
NOTE_BLOCK_NUMBER (insn) = current_block_number;
}
}
if (n_blocks != next_block_number)
abort ();
return block_vector;
}
/* Given BLOCK_VECTOR which was returned by identify_blocks,
and a revised instruction chain, rebuild the tree structure
of BLOCK nodes to correspond to the new order of RTL.
The new block tree is inserted below TOP_BLOCK.
Returns the current top-level block. */
tree
reorder_blocks (block_vector, block, insns)
tree *block_vector;
tree block;
rtx insns;
{
tree current_block = block;
rtx insn;
if (block_vector == 0)
return block;
/* Prune the old trees away, so that it doesn't get in the way. */
BLOCK_SUBBLOCKS (current_block) = 0;
BLOCK_CHAIN (current_block) = 0;
for (insn = insns; insn; insn = NEXT_INSN (insn))
if (GET_CODE (insn) == NOTE)
{
if (NOTE_LINE_NUMBER (insn) == NOTE_INSN_BLOCK_BEG)
{
tree block = block_vector[NOTE_BLOCK_NUMBER (insn)];
/* If we have seen this block before, copy it. */
if (TREE_ASM_WRITTEN (block))
block = copy_node (block);
BLOCK_SUBBLOCKS (block) = 0;
TREE_ASM_WRITTEN (block) = 1;
BLOCK_SUPERCONTEXT (block) = current_block;
BLOCK_CHAIN (block) = BLOCK_SUBBLOCKS (current_block);
BLOCK_SUBBLOCKS (current_block) = block;
current_block = block;
NOTE_SOURCE_FILE (insn) = 0;
}
if (NOTE_LINE_NUMBER (insn) == NOTE_INSN_BLOCK_END)
{
BLOCK_SUBBLOCKS (current_block)
= blocks_nreverse (BLOCK_SUBBLOCKS (current_block));
current_block = BLOCK_SUPERCONTEXT (current_block);
NOTE_SOURCE_FILE (insn) = 0;
}
}
BLOCK_SUBBLOCKS (current_block)
= blocks_nreverse (BLOCK_SUBBLOCKS (current_block));
return current_block;
}
/* Reverse the order of elements in the chain T of blocks,
and return the new head of the chain (old last element). */
static tree
blocks_nreverse (t)
tree t;
{
register tree prev = 0, decl, next;
for (decl = t; decl; decl = next)
{
next = BLOCK_CHAIN (decl);
BLOCK_CHAIN (decl) = prev;
prev = decl;
}
return prev;
}
/* Count the subblocks of the list starting with BLOCK, and list them
all into the vector VECTOR. Also clear TREE_ASM_WRITTEN in all
blocks. */
static int
all_blocks (block, vector)
tree block;
tree *vector;
{
int n_blocks = 0;
while (block)
{
TREE_ASM_WRITTEN (block) = 0;
/* Record this block. */
if (vector)
vector[n_blocks] = block;
++n_blocks;
/* Record the subblocks, and their subblocks... */
n_blocks += all_blocks (BLOCK_SUBBLOCKS (block),
vector ? vector + n_blocks : 0);
block = BLOCK_CHAIN (block);
}
return n_blocks;
}
/* Build bytecode call descriptor for function SUBR. */
rtx
bc_build_calldesc (subr)
tree subr;
{
tree calldesc = 0, arg;
int nargs = 0;
/* Build the argument description vector in reverse order. */
DECL_ARGUMENTS (subr) = nreverse (DECL_ARGUMENTS (subr));
nargs = 0;
for (arg = DECL_ARGUMENTS (subr); arg; arg = TREE_CHAIN (arg))
{
++nargs;
calldesc = tree_cons ((tree) 0, size_in_bytes (TREE_TYPE (arg)), calldesc);
calldesc = tree_cons ((tree) 0, bc_runtime_type_code (TREE_TYPE (arg)), calldesc);
}
DECL_ARGUMENTS (subr) = nreverse (DECL_ARGUMENTS (subr));
/* Prepend the function's return type. */
calldesc = tree_cons ((tree) 0,
size_in_bytes (TREE_TYPE (TREE_TYPE (subr))),
calldesc);
calldesc = tree_cons ((tree) 0,
bc_runtime_type_code (TREE_TYPE (TREE_TYPE (subr))),
calldesc);
/* Prepend the arg count. */
calldesc = tree_cons ((tree) 0, build_int_2 (nargs, 0), calldesc);
/* Output the call description vector and get its address. */
calldesc = build_nt (CONSTRUCTOR, (tree) 0, calldesc);
TREE_TYPE (calldesc) = build_array_type (integer_type_node,
build_index_type (build_int_2 (nargs * 2, 0)));
return output_constant_def (calldesc);
}
/* Generate RTL for the start of the function SUBR (a FUNCTION_DECL tree node)
and initialize static variables for generating RTL for the statements
of the function. */
void
init_function_start (subr, filename, line)
tree subr;
char *filename;
int line;
{
if (output_bytecode)
{
this_function_decl = subr;
this_function_calldesc = bc_build_calldesc (subr);
local_vars_size = 0;
stack_depth = 0;
max_stack_depth = 0;
stmt_expr_depth = 0;
return;
}
init_stmt_for_function ();
cse_not_expected = ! optimize;
/* Caller save not needed yet. */
caller_save_needed = 0;
/* No stack slots have been made yet. */
stack_slot_list = 0;
/* There is no stack slot for handling nonlocal gotos. */
nonlocal_goto_handler_slot = 0;
nonlocal_goto_stack_level = 0;
/* No labels have been declared for nonlocal use. */
nonlocal_labels = 0;
/* No function calls so far in this function. */
function_call_count = 0;
/* No parm regs have been allocated.
(This is important for output_inline_function.) */
max_parm_reg = LAST_VIRTUAL_REGISTER + 1;
/* Initialize the RTL mechanism. */
init_emit ();
/* Initialize the queue of pending postincrement and postdecrements,
and some other info in expr.c. */
init_expr ();
/* We haven't done register allocation yet. */
reg_renumber = 0;
init_const_rtx_hash_table ();
current_function_name = (*decl_printable_name) (subr, 2);
/* Nonzero if this is a nested function that uses a static chain. */
current_function_needs_context
= (decl_function_context (current_function_decl) != 0
&& ! DECL_NO_STATIC_CHAIN (current_function_decl));
/* Set if a call to setjmp is seen. */
current_function_calls_setjmp = 0;
/* Set if a call to longjmp is seen. */
current_function_calls_longjmp = 0;
current_function_calls_alloca = 0;
current_function_has_nonlocal_label = 0;
current_function_has_nonlocal_goto = 0;
current_function_contains_functions = 0;
current_function_is_thunk = 0;
current_function_returns_pcc_struct = 0;
current_function_returns_struct = 0;
current_function_epilogue_delay_list = 0;
current_function_uses_const_pool = 0;
current_function_uses_pic_offset_table = 0;
/* We have not yet needed to make a label to jump to for tail-recursion. */
tail_recursion_label = 0;
/* We haven't had a need to make a save area for ap yet. */
arg_pointer_save_area = 0;
/* No stack slots allocated yet. */
frame_offset = 0;
/* No SAVE_EXPRs in this function yet. */
save_expr_regs = 0;
/* No RTL_EXPRs in this function yet. */
rtl_expr_chain = 0;
/* Set up to allocate temporaries. */
init_temp_slots ();
/* Within function body, compute a type's size as soon it is laid out. */
immediate_size_expand++;
/* We haven't made any trampolines for this function yet. */
trampoline_list = 0;
init_pending_stack_adjust ();
inhibit_defer_pop = 0;
current_function_outgoing_args_size = 0;
/* Prevent ever trying to delete the first instruction of a function.
Also tell final how to output a linenum before the function prologue. */
emit_line_note (filename, line);
/* Make sure first insn is a note even if we don't want linenums.
This makes sure the first insn will never be deleted.
Also, final expects a note to appear there. */
emit_note (NULL_PTR, NOTE_INSN_DELETED);
/* Set flags used by final.c. */
if (aggregate_value_p (DECL_RESULT (subr)))
{
#ifdef PCC_STATIC_STRUCT_RETURN
current_function_returns_pcc_struct = 1;
#endif
current_function_returns_struct = 1;
}
/* Warn if this value is an aggregate type,
regardless of which calling convention we are using for it. */
if (warn_aggregate_return
&& AGGREGATE_TYPE_P (TREE_TYPE (DECL_RESULT (subr))))
warning ("function returns an aggregate");
current_function_returns_pointer
= POINTER_TYPE_P (TREE_TYPE (DECL_RESULT (subr)));
/* Indicate that we need to distinguish between the return value of the
present function and the return value of a function being called. */
rtx_equal_function_value_matters = 1;
/* Indicate that we have not instantiated virtual registers yet. */
virtuals_instantiated = 0;
/* Indicate we have no need of a frame pointer yet. */
frame_pointer_needed = 0;
/* By default assume not varargs or stdarg. */
current_function_varargs = 0;
current_function_stdarg = 0;
}
/* Indicate that the current function uses extra args
not explicitly mentioned in the argument list in any fashion. */
void
mark_varargs ()
{
current_function_varargs = 1;
}
/* Expand a call to __main at the beginning of a possible main function. */
#if defined(INIT_SECTION_ASM_OP) && !defined(INVOKE__main)
#undef HAS_INIT_SECTION
#define HAS_INIT_SECTION
#endif
void
expand_main_function ()
{
if (!output_bytecode)
{
/* The zero below avoids a possible parse error */
0;
#if !defined (HAS_INIT_SECTION)
emit_library_call (gen_rtx (SYMBOL_REF, Pmode, NAME__MAIN), 0,
VOIDmode, 0);
#endif /* not HAS_INIT_SECTION */
}
}
extern struct obstack permanent_obstack;
/* Expand start of bytecode function. See comment at
expand_function_start below for details. */
void
bc_expand_function_start (subr, parms_have_cleanups)
tree subr;
int parms_have_cleanups;
{
char label[20], *name;
static int nlab;
tree thisarg;
int argsz;
if (TREE_PUBLIC (subr))
bc_globalize_label (IDENTIFIER_POINTER (DECL_NAME (subr)));
#ifdef DEBUG_PRINT_CODE
fprintf (stderr, "\n<func %s>\n", IDENTIFIER_POINTER (DECL_NAME (subr)));
#endif
for (argsz = 0, thisarg = DECL_ARGUMENTS (subr); thisarg; thisarg = TREE_CHAIN (thisarg))
{
if (DECL_RTL (thisarg))
abort (); /* Should be NULL here I think. */
else if (TREE_CONSTANT (DECL_SIZE (thisarg)))
{
DECL_RTL (thisarg) = bc_gen_rtx ((char *) 0, argsz, (struct bc_label *) 0);
argsz += TREE_INT_CST_LOW (DECL_SIZE (thisarg));
}
else
{
/* Variable-sized objects are pointers to their storage. */
DECL_RTL (thisarg) = bc_gen_rtx ((char *) 0, argsz, (struct bc_label *) 0);
argsz += POINTER_SIZE;
}
}
bc_begin_function (xstrdup (IDENTIFIER_POINTER (DECL_NAME (subr))));
ASM_GENERATE_INTERNAL_LABEL (label, "LX", nlab);
++nlab;
name = (char *) obstack_copy0 (&permanent_obstack, label, strlen (label));
this_function_callinfo = bc_gen_rtx (name, 0, (struct bc_label *) 0);
this_function_bytecode
= bc_emit_trampoline (BYTECODE_LABEL (this_function_callinfo));
}
/* Expand end of bytecode function. See details the comment of
expand_function_end(), below. */
void
bc_expand_function_end ()
{
char *ptrconsts;
expand_null_return ();
/* Emit any fixup code. This must be done before the call to
to BC_END_FUNCTION (), since that will cause the bytecode
segment to be finished off and closed. */
expand_fixups (NULL_RTX);
ptrconsts = bc_end_function ();
bc_align_const (2 /* INT_ALIGN */);
/* If this changes also make sure to change bc-interp.h! */
bc_emit_const_labeldef (BYTECODE_LABEL (this_function_callinfo));
bc_emit_const ((char *) &max_stack_depth, sizeof max_stack_depth);
bc_emit_const ((char *) &local_vars_size, sizeof local_vars_size);
bc_emit_const_labelref (this_function_bytecode, 0);
bc_emit_const_labelref (ptrconsts, 0);
bc_emit_const_labelref (BYTECODE_LABEL (this_function_calldesc), 0);
}
/* Start the RTL for a new function, and set variables used for
emitting RTL.
SUBR is the FUNCTION_DECL node.
PARMS_HAVE_CLEANUPS is nonzero if there are cleanups associated with
the function's parameters, which must be run at any return statement. */
void
expand_function_start (subr, parms_have_cleanups)
tree subr;
int parms_have_cleanups;
{
register int i;
tree tem;
rtx last_ptr;
if (output_bytecode)
{
bc_expand_function_start (subr, parms_have_cleanups);
return;
}
/* Make sure volatile mem refs aren't considered
valid operands of arithmetic insns. */
init_recog_no_volatile ();
/* If function gets a static chain arg, store it in the stack frame.
Do this first, so it gets the first stack slot offset. */
if (current_function_needs_context)
{
last_ptr = assign_stack_local (Pmode, GET_MODE_SIZE (Pmode), 0);
#ifdef SMALL_REGISTER_CLASSES
/* Delay copying static chain if it is not a register to avoid
conflicts with regs used for parameters. */
if (! SMALL_REGISTER_CLASSES
|| GET_CODE (static_chain_incoming_rtx) == REG)
#endif
emit_move_insn (last_ptr, static_chain_incoming_rtx);
}
/* If the parameters of this function need cleaning up, get a label
for the beginning of the code which executes those cleanups. This must
be done before doing anything with return_label. */
if (parms_have_cleanups)
cleanup_label = gen_label_rtx ();
else
cleanup_label = 0;
/* Make the label for return statements to jump to, if this machine
does not have a one-instruction return and uses an epilogue,
or if it returns a structure, or if it has parm cleanups. */
#ifdef HAVE_return
if (cleanup_label == 0 && HAVE_return
&& ! current_function_returns_pcc_struct
&& ! (current_function_returns_struct && ! optimize))
return_label = 0;
else
return_label = gen_label_rtx ();
#else
return_label = gen_label_rtx ();
#endif
/* Initialize rtx used to return the value. */
/* Do this before assign_parms so that we copy the struct value address
before any library calls that assign parms might generate. */
/* Decide whether to return the value in memory or in a register. */
if (aggregate_value_p (DECL_RESULT (subr)))
{
/* Returning something that won't go in a register. */
register rtx value_address = 0;
#ifdef PCC_STATIC_STRUCT_RETURN
if (current_function_returns_pcc_struct)
{
int size = int_size_in_bytes (TREE_TYPE (DECL_RESULT (subr)));
value_address = assemble_static_space (size);
}
else
#endif
{
/* Expect to be passed the address of a place to store the value.
If it is passed as an argument, assign_parms will take care of
it. */
if (struct_value_incoming_rtx)
{
value_address = gen_reg_rtx (Pmode);
emit_move_insn (value_address, struct_value_incoming_rtx);
}
}
if (value_address)
{
DECL_RTL (DECL_RESULT (subr))
= gen_rtx (MEM, DECL_MODE (DECL_RESULT (subr)), value_address);
MEM_IN_STRUCT_P (DECL_RTL (DECL_RESULT (subr)))
= AGGREGATE_TYPE_P (TREE_TYPE (DECL_RESULT (subr)));
}
}
else if (DECL_MODE (DECL_RESULT (subr)) == VOIDmode)
/* If return mode is void, this decl rtl should not be used. */
DECL_RTL (DECL_RESULT (subr)) = 0;
else if (parms_have_cleanups)
{
/* If function will end with cleanup code for parms,
compute the return values into a pseudo reg,
which we will copy into the true return register
after the cleanups are done. */
enum machine_mode mode = DECL_MODE (DECL_RESULT (subr));
#ifdef PROMOTE_FUNCTION_RETURN
tree type = TREE_TYPE (DECL_RESULT (subr));
int unsignedp = TREE_UNSIGNED (type);
mode = promote_mode (type, mode, &unsignedp, 1);
#endif
DECL_RTL (DECL_RESULT (subr)) = gen_reg_rtx (mode);
}
else
/* Scalar, returned in a register. */
{
#ifdef FUNCTION_OUTGOING_VALUE
DECL_RTL (DECL_RESULT (subr))
= FUNCTION_OUTGOING_VALUE (TREE_TYPE (DECL_RESULT (subr)), subr);
#else
DECL_RTL (DECL_RESULT (subr))
= FUNCTION_VALUE (TREE_TYPE (DECL_RESULT (subr)), subr);
#endif
/* Mark this reg as the function's return value. */
if (GET_CODE (DECL_RTL (DECL_RESULT (subr))) == REG)
{
REG_FUNCTION_VALUE_P (DECL_RTL (DECL_RESULT (subr))) = 1;
/* Needed because we may need to move this to memory
in case it's a named return value whose address is taken. */
DECL_REGISTER (DECL_RESULT (subr)) = 1;
}
}
/* Initialize rtx for parameters and local variables.
In some cases this requires emitting insns. */
assign_parms (subr, 0);
#ifdef SMALL_REGISTER_CLASSES
/* Copy the static chain now if it wasn't a register. The delay is to
avoid conflicts with the parameter passing registers. */
if (SMALL_REGISTER_CLASSES && current_function_needs_context)
if (GET_CODE (static_chain_incoming_rtx) != REG)
emit_move_insn (last_ptr, static_chain_incoming_rtx);
#endif
/* The following was moved from init_function_start.
The move is supposed to make sdb output more accurate. */
/* Indicate the beginning of the function body,
as opposed to parm setup. */
emit_note (NULL_PTR, NOTE_INSN_FUNCTION_BEG);
/* If doing stupid allocation, mark parms as born here. */
if (GET_CODE (get_last_insn ()) != NOTE)
emit_note (NULL_PTR, NOTE_INSN_DELETED);
parm_birth_insn = get_last_insn ();
if (obey_regdecls)
{
for (i = LAST_VIRTUAL_REGISTER + 1; i < max_parm_reg; i++)
use_variable (regno_reg_rtx[i]);
if (current_function_internal_arg_pointer != virtual_incoming_args_rtx)
use_variable (current_function_internal_arg_pointer);
}
context_display = 0;
if (current_function_needs_context)
{
/* Fetch static chain values for containing functions. */
tem = decl_function_context (current_function_decl);
/* If not doing stupid register allocation copy the static chain
pointer into a pseudo. If we have small register classes, copy
the value from memory if static_chain_incoming_rtx is a REG. If
we do stupid register allocation, we use the stack address
generated above. */
if (tem && ! obey_regdecls)
{
#ifdef SMALL_REGISTER_CLASSES
/* If the static chain originally came in a register, put it back
there, then move it out in the next insn. The reason for
this peculiar code is to satisfy function integration. */
if (SMALL_REGISTER_CLASSES
&& GET_CODE (static_chain_incoming_rtx) == REG)
emit_move_insn (static_chain_incoming_rtx, last_ptr);
#endif
last_ptr = copy_to_reg (static_chain_incoming_rtx);
}
while (tem)
{
tree rtlexp = make_node (RTL_EXPR);
RTL_EXPR_RTL (rtlexp) = last_ptr;
context_display = tree_cons (tem, rtlexp, context_display);
tem = decl_function_context (tem);
if (tem == 0)
break;
/* Chain thru stack frames, assuming pointer to next lexical frame
is found at the place we always store it. */
#ifdef FRAME_GROWS_DOWNWARD
last_ptr = plus_constant (last_ptr, - GET_MODE_SIZE (Pmode));
#endif
last_ptr = copy_to_reg (gen_rtx (MEM, Pmode,
memory_address (Pmode, last_ptr)));
/* If we are not optimizing, ensure that we know that this
piece of context is live over the entire function. */
if (! optimize)
save_expr_regs = gen_rtx (EXPR_LIST, VOIDmode, last_ptr,
save_expr_regs);
}
}
/* After the display initializations is where the tail-recursion label
should go, if we end up needing one. Ensure we have a NOTE here
since some things (like trampolines) get placed before this. */
tail_recursion_reentry = emit_note (NULL_PTR, NOTE_INSN_DELETED);
/* Evaluate now the sizes of any types declared among the arguments. */
for (tem = nreverse (get_pending_sizes ()); tem; tem = TREE_CHAIN (tem))
{
expand_expr (TREE_VALUE (tem), const0_rtx, VOIDmode,
EXPAND_MEMORY_USE_BAD);
/* Flush the queue in case this parameter declaration has
side-effects. */
emit_queue ();
}
/* Make sure there is a line number after the function entry setup code. */
force_next_line_note ();
}
/* Generate RTL for the end of the current function.
FILENAME and LINE are the current position in the source file.
It is up to language-specific callers to do cleanups for parameters--
or else, supply 1 for END_BINDINGS and we will call expand_end_bindings. */
void
expand_function_end (filename, line, end_bindings)
char *filename;
int line;
int end_bindings;
{
register int i;
tree link;
#ifdef TRAMPOLINE_TEMPLATE
static rtx initial_trampoline;
#endif
if (output_bytecode)
{
bc_expand_function_end ();
return;
}
#ifdef NON_SAVING_SETJMP
/* Don't put any variables in registers if we call setjmp
on a machine that fails to restore the registers. */
if (NON_SAVING_SETJMP && current_function_calls_setjmp)
{
if (DECL_INITIAL (current_function_decl) != error_mark_node)
setjmp_protect (DECL_INITIAL (current_function_decl));
setjmp_protect_args ();
}
#endif
/* Save the argument pointer if a save area was made for it. */
if (arg_pointer_save_area)
{
rtx x = gen_move_insn (arg_pointer_save_area, virtual_incoming_args_rtx);
emit_insn_before (x, tail_recursion_reentry);
}
/* Initialize any trampolines required by this function. */
for (link = trampoline_list; link; link = TREE_CHAIN (link))
{
tree function = TREE_PURPOSE (link);
rtx context = lookup_static_chain (function);
rtx tramp = RTL_EXPR_RTL (TREE_VALUE (link));
rtx blktramp;
rtx seq;
#ifdef TRAMPOLINE_TEMPLATE
/* First make sure this compilation has a template for
initializing trampolines. */
if (initial_trampoline == 0)
{
end_temporary_allocation ();
initial_trampoline
= gen_rtx (MEM, BLKmode, assemble_trampoline_template ());
resume_temporary_allocation ();
}
#endif
/* Generate insns to initialize the trampoline. */
start_sequence ();
tramp = round_trampoline_addr (XEXP (tramp, 0));
#ifdef TRAMPOLINE_TEMPLATE
blktramp = change_address (initial_trampoline, BLKmode, tramp);
emit_block_move (blktramp, initial_trampoline,
GEN_INT (TRAMPOLINE_SIZE),
TRAMPOLINE_ALIGNMENT / BITS_PER_UNIT);
#endif
INITIALIZE_TRAMPOLINE (tramp, XEXP (DECL_RTL (function), 0), context);
seq = get_insns ();
end_sequence ();
/* Put those insns at entry to the containing function (this one). */
emit_insns_before (seq, tail_recursion_reentry);
}
/* If we are doing stack checking and this function makes calls,
do a stack probe at the start of the function to ensure we have enough
space for another stack frame. */
if (flag_stack_check && ! STACK_CHECK_BUILTIN)
{
rtx insn, seq;
for (insn = get_insns (); insn; insn = NEXT_INSN (insn))
if (GET_CODE (insn) == CALL_INSN)
{
start_sequence ();
probe_stack_range (STACK_CHECK_PROTECT,
GEN_INT (STACK_CHECK_MAX_FRAME_SIZE));
seq = get_insns ();
end_sequence ();
emit_insns_before (seq, tail_recursion_reentry);
break;
}
}
/* Warn about unused parms if extra warnings were specified. */
if (warn_unused && extra_warnings)
{
tree decl;
for (decl = DECL_ARGUMENTS (current_function_decl);
decl; decl = TREE_CHAIN (decl))
if (! TREE_USED (decl) && TREE_CODE (decl) == PARM_DECL
&& DECL_NAME (decl) && ! DECL_ARTIFICIAL (decl))
warning_with_decl (decl, "unused parameter `%s'");
}
/* Delete handlers for nonlocal gotos if nothing uses them. */
if (nonlocal_goto_handler_slot != 0 && !current_function_has_nonlocal_label)
delete_handlers ();
/* End any sequences that failed to be closed due to syntax errors. */
while (in_sequence_p ())
end_sequence ();
/* Outside function body, can't compute type's actual size
until next function's body starts. */
immediate_size_expand--;
/* If doing stupid register allocation,
mark register parms as dying here. */
if (obey_regdecls)
{
rtx tem;
for (i = LAST_VIRTUAL_REGISTER + 1; i < max_parm_reg; i++)
use_variable (regno_reg_rtx[i]);
/* Likewise for the regs of all the SAVE_EXPRs in the function. */
for (tem = save_expr_regs; tem; tem = XEXP (tem, 1))
{
use_variable (XEXP (tem, 0));
use_variable_after (XEXP (tem, 0), parm_birth_insn);
}
if (current_function_internal_arg_pointer != virtual_incoming_args_rtx)
use_variable (current_function_internal_arg_pointer);
}
clear_pending_stack_adjust ();
do_pending_stack_adjust ();
/* Mark the end of the function body.
If control reaches this insn, the function can drop through
without returning a value. */
emit_note (NULL_PTR, NOTE_INSN_FUNCTION_END);
/* Must mark the last line number note in the function, so that the test
coverage code can avoid counting the last line twice. This just tells
the code to ignore the immediately following line note, since there
already exists a copy of this note somewhere above. This line number
note is still needed for debugging though, so we can't delete it. */
if (flag_test_coverage)
emit_note (NULL_PTR, NOTE_REPEATED_LINE_NUMBER);
/* Output a linenumber for the end of the function.
SDB depends on this. */
emit_line_note_force (filename, line);
/* Output the label for the actual return from the function,
if one is expected. This happens either because a function epilogue
is used instead of a return instruction, or because a return was done
with a goto in order to run local cleanups, or because of pcc-style
structure returning. */
if (return_label)
emit_label (return_label);
/* C++ uses this. */
if (end_bindings)
expand_end_bindings (0, 0, 0);
/* Now handle any leftover exception regions that may have been
created for the parameters. */
{
rtx last = get_last_insn ();
rtx label;
expand_leftover_cleanups ();
/* If the above emitted any code, may sure we jump around it. */
if (last != get_last_insn ())
{
label = gen_label_rtx ();
last = emit_jump_insn_after (gen_jump (label), last);
last = emit_barrier_after (last);
emit_label (label);
}
}
/* If we had calls to alloca, and this machine needs
an accurate stack pointer to exit the function,
insert some code to save and restore the stack pointer. */
#ifdef EXIT_IGNORE_STACK
if (! EXIT_IGNORE_STACK)
#endif
if (current_function_calls_alloca)
{
rtx tem = 0;
emit_stack_save (SAVE_FUNCTION, &tem, parm_birth_insn);
emit_stack_restore (SAVE_FUNCTION, tem, NULL_RTX);
}
/* If scalar return value was computed in a pseudo-reg,
copy that to the hard return register. */
if (DECL_RTL (DECL_RESULT (current_function_decl)) != 0
&& GET_CODE (DECL_RTL (DECL_RESULT (current_function_decl))) == REG
&& (REGNO (DECL_RTL (DECL_RESULT (current_function_decl)))
>= FIRST_PSEUDO_REGISTER))
{
rtx real_decl_result;
#ifdef FUNCTION_OUTGOING_VALUE
real_decl_result
= FUNCTION_OUTGOING_VALUE (TREE_TYPE (DECL_RESULT (current_function_decl)),
current_function_decl);
#else
real_decl_result
= FUNCTION_VALUE (TREE_TYPE (DECL_RESULT (current_function_decl)),
current_function_decl);
#endif
REG_FUNCTION_VALUE_P (real_decl_result) = 1;
/* If this is a BLKmode structure being returned in registers, then use
the mode computed in expand_return. */
if (GET_MODE (real_decl_result) == BLKmode)
PUT_MODE (real_decl_result,
GET_MODE (DECL_RTL (DECL_RESULT (current_function_decl))));
emit_move_insn (real_decl_result,
DECL_RTL (DECL_RESULT (current_function_decl)));
emit_insn (gen_rtx (USE, VOIDmode, real_decl_result));
/* The delay slot scheduler assumes that current_function_return_rtx
holds the hard register containing the return value, not a temporary
pseudo. */
current_function_return_rtx = real_decl_result;
}
/* If returning a structure, arrange to return the address of the value
in a place where debuggers expect to find it.
If returning a structure PCC style,
the caller also depends on this value.
And current_function_returns_pcc_struct is not necessarily set. */
if (current_function_returns_struct
|| current_function_returns_pcc_struct)
{
rtx value_address = XEXP (DECL_RTL (DECL_RESULT (current_function_decl)), 0);
tree type = TREE_TYPE (DECL_RESULT (current_function_decl));
#ifdef FUNCTION_OUTGOING_VALUE
rtx outgoing
= FUNCTION_OUTGOING_VALUE (build_pointer_type (type),
current_function_decl);
#else
rtx outgoing
= FUNCTION_VALUE (build_pointer_type (type),
current_function_decl);
#endif
/* Mark this as a function return value so integrate will delete the
assignment and USE below when inlining this function. */
REG_FUNCTION_VALUE_P (outgoing) = 1;
emit_move_insn (outgoing, value_address);
use_variable (outgoing);
}
/* Output a return insn if we are using one.
Otherwise, let the rtl chain end here, to drop through
into the epilogue. */
#ifdef HAVE_return
if (HAVE_return)
{
emit_jump_insn (gen_return ());
emit_barrier ();
}
#endif
/* Fix up any gotos that jumped out to the outermost
binding level of the function.
Must follow emitting RETURN_LABEL. */
/* If you have any cleanups to do at this point,
and they need to create temporary variables,
then you will lose. */
expand_fixups (get_insns ());
}
/* These arrays record the INSN_UIDs of the prologue and epilogue insns. */
static int *prologue;
static int *epilogue;
/* Create an array that records the INSN_UIDs of INSNS (either a sequence
or a single insn). */
static int *
record_insns (insns)
rtx insns;
{
int *vec;
if (GET_CODE (insns) == SEQUENCE)
{
int len = XVECLEN (insns, 0);
vec = (int *) oballoc ((len + 1) * sizeof (int));
vec[len] = 0;
while (--len >= 0)
vec[len] = INSN_UID (XVECEXP (insns, 0, len));
}
else
{
vec = (int *) oballoc (2 * sizeof (int));
vec[0] = INSN_UID (insns);
vec[1] = 0;
}
return vec;
}
/* Determine how many INSN_UIDs in VEC are part of INSN. */
static int
contains (insn, vec)
rtx insn;
int *vec;
{
register int i, j;
if (GET_CODE (insn) == INSN
&& GET_CODE (PATTERN (insn)) == SEQUENCE)
{
int count = 0;
for (i = XVECLEN (PATTERN (insn), 0) - 1; i >= 0; i--)
for (j = 0; vec[j]; j++)
if (INSN_UID (XVECEXP (PATTERN (insn), 0, i)) == vec[j])
count++;
return count;
}
else
{
for (j = 0; vec[j]; j++)
if (INSN_UID (insn) == vec[j])
return 1;
}
return 0;
}
/* Generate the prologue and epilogue RTL if the machine supports it. Thread
this into place with notes indicating where the prologue ends and where
the epilogue begins. Update the basic block information when possible. */
void
thread_prologue_and_epilogue_insns (f)
rtx f;
{
#ifdef HAVE_prologue
if (HAVE_prologue)
{
rtx head, seq, insn;
/* The first insn (a NOTE_INSN_DELETED) is followed by zero or more
prologue insns and a NOTE_INSN_PROLOGUE_END. */
emit_note_after (NOTE_INSN_PROLOGUE_END, f);
seq = gen_prologue ();
head = emit_insn_after (seq, f);
/* Include the new prologue insns in the first block. Ignore them
if they form a basic block unto themselves. */
if (basic_block_head && n_basic_blocks
&& GET_CODE (basic_block_head[0]) != CODE_LABEL)
basic_block_head[0] = NEXT_INSN (f);
/* Retain a map of the prologue insns. */
prologue = record_insns (GET_CODE (seq) == SEQUENCE ? seq : head);
}
else
#endif
prologue = 0;
#ifdef HAVE_epilogue
if (HAVE_epilogue)
{
rtx insn = get_last_insn ();
rtx prev = prev_nonnote_insn (insn);
/* If we end with a BARRIER, we don't need an epilogue. */
if (! (prev && GET_CODE (prev) == BARRIER))
{
rtx tail, seq, tem;
rtx first_use = 0;
rtx last_use = 0;
/* The last basic block ends with a NOTE_INSN_EPILOGUE_BEG, the
epilogue insns, the USE insns at the end of a function,
the jump insn that returns, and then a BARRIER. */
/* Move the USE insns at the end of a function onto a list. */
while (prev
&& GET_CODE (prev) == INSN
&& GET_CODE (PATTERN (prev)) == USE)
{
tem = prev;
prev = prev_nonnote_insn (prev);
NEXT_INSN (PREV_INSN (tem)) = NEXT_INSN (tem);
PREV_INSN (NEXT_INSN (tem)) = PREV_INSN (tem);
if (first_use)
{
NEXT_INSN (tem) = first_use;
PREV_INSN (first_use) = tem;
}
first_use = tem;
if (!last_use)
last_use = tem;
}
emit_barrier_after (insn);
seq = gen_epilogue ();
tail = emit_jump_insn_after (seq, insn);
/* Insert the USE insns immediately before the return insn, which
must be the first instruction before the final barrier. */
if (first_use)
{
tem = prev_nonnote_insn (get_last_insn ());
NEXT_INSN (PREV_INSN (tem)) = first_use;
PREV_INSN (first_use) = PREV_INSN (tem);
PREV_INSN (tem) = last_use;
NEXT_INSN (last_use) = tem;
}
emit_note_after (NOTE_INSN_EPILOGUE_BEG, insn);
/* Include the new epilogue insns in the last block. Ignore
them if they form a basic block unto themselves. */
if (basic_block_end && n_basic_blocks
&& GET_CODE (basic_block_end[n_basic_blocks - 1]) != JUMP_INSN)
basic_block_end[n_basic_blocks - 1] = tail;
/* Retain a map of the epilogue insns. */
epilogue = record_insns (GET_CODE (seq) == SEQUENCE ? seq : tail);
return;
}
}
#endif
epilogue = 0;
}
/* Reposition the prologue-end and epilogue-begin notes after instruction
scheduling and delayed branch scheduling. */
void
reposition_prologue_and_epilogue_notes (f)
rtx f;
{
#if defined (HAVE_prologue) || defined (HAVE_epilogue)
/* Reposition the prologue and epilogue notes. */
if (n_basic_blocks)
{
rtx next, prev;
int len;
if (prologue)
{
register rtx insn, note = 0;
/* Scan from the beginning until we reach the last prologue insn.
We apparently can't depend on basic_block_{head,end} after
reorg has run. */
for (len = 0; prologue[len]; len++)
;
for (insn = f; len && insn; insn = NEXT_INSN (insn))
{
if (GET_CODE (insn) == NOTE)
{
if (NOTE_LINE_NUMBER (insn) == NOTE_INSN_PROLOGUE_END)
note = insn;
}
else if ((len -= contains (insn, prologue)) == 0)
{
/* Find the prologue-end note if we haven't already, and
move it to just after the last prologue insn. */
if (note == 0)
{
for (note = insn; note = NEXT_INSN (note);)
if (GET_CODE (note) == NOTE
&& NOTE_LINE_NUMBER (note) == NOTE_INSN_PROLOGUE_END)
break;
}
next = NEXT_INSN (note);
prev = PREV_INSN (note);
if (prev)
NEXT_INSN (prev) = next;
if (next)
PREV_INSN (next) = prev;
add_insn_after (note, insn);
}
}
}
if (epilogue)
{
register rtx insn, note = 0;
/* Scan from the end until we reach the first epilogue insn.
We apparently can't depend on basic_block_{head,end} after
reorg has run. */
for (len = 0; epilogue[len]; len++)
;
for (insn = get_last_insn (); len && insn; insn = PREV_INSN (insn))
{
if (GET_CODE (insn) == NOTE)
{
if (NOTE_LINE_NUMBER (insn) == NOTE_INSN_EPILOGUE_BEG)
note = insn;
}
else if ((len -= contains (insn, epilogue)) == 0)
{
/* Find the epilogue-begin note if we haven't already, and
move it to just before the first epilogue insn. */
if (note == 0)
{
for (note = insn; note = PREV_INSN (note);)
if (GET_CODE (note) == NOTE
&& NOTE_LINE_NUMBER (note) == NOTE_INSN_EPILOGUE_BEG)
break;
}
next = NEXT_INSN (note);
prev = PREV_INSN (note);
if (prev)
NEXT_INSN (prev) = next;
if (next)
PREV_INSN (next) = prev;
add_insn_after (note, PREV_INSN (insn));
}
}
}
}
#endif /* HAVE_prologue or HAVE_epilogue */
}