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/* Language-independent node constructors for parse phase of GNU compiler.
Copyright (C) 1987, 1988, 1992, 1993, 1994, 1995, 1996, 1997, 1998,
1999, 2000, 2001, 2002, 2003, 2004 Free Software Foundation, Inc.
This file is part of GCC.
GCC 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.
GCC 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 GCC; see the file COPYING. If not, write to the Free
Software Foundation, 59 Temple Place - Suite 330, Boston, MA
02111-1307, USA. */
/* This file contains the low level primitives for operating on tree nodes,
including allocation, list operations, interning of identifiers,
construction of data type nodes and statement nodes,
and construction of type conversion nodes. It also contains
tables index by tree code that describe how to take apart
nodes of that code.
It is intended to be language-independent, but occasionally
calls language-dependent routines defined (for C) in typecheck.c. */
#include "config.h"
#include "system.h"
#include "coretypes.h"
#include "tm.h"
#include "flags.h"
#include "tree.h"
#include "real.h"
#include "tm_p.h"
#include "function.h"
#include "obstack.h"
#include "toplev.h"
#include "ggc.h"
#include "hashtab.h"
#include "output.h"
#include "target.h"
#include "langhooks.h"
/* obstack.[ch] explicitly declined to prototype this. */
extern int _obstack_allocated_p (struct obstack *h, void *obj);
#ifdef GATHER_STATISTICS
/* Statistics-gathering stuff. */
int tree_node_counts[(int) all_kinds];
int tree_node_sizes[(int) all_kinds];
/* Keep in sync with tree.h:enum tree_node_kind. */
static const char * const tree_node_kind_names[] = {
"decls",
"types",
"blocks",
"stmts",
"refs",
"exprs",
"constants",
"identifiers",
"perm_tree_lists",
"temp_tree_lists",
"vecs",
"random kinds",
"lang_decl kinds",
"lang_type kinds"
};
#endif /* GATHER_STATISTICS */
/* Unique id for next decl created. */
static GTY(()) int next_decl_uid;
/* Unique id for next type created. */
static GTY(()) int next_type_uid = 1;
/* Since we cannot rehash a type after it is in the table, we have to
keep the hash code. */
struct type_hash GTY(())
{
unsigned long hash;
tree type;
};
/* Initial size of the hash table (rounded to next prime). */
#define TYPE_HASH_INITIAL_SIZE 1000
/* Now here is the hash table. When recording a type, it is added to
the slot whose index is the hash code. Note that the hash table is
used for several kinds of types (function types, array types and
array index range types, for now). While all these live in the
same table, they are completely independent, and the hash code is
computed differently for each of these. */
static GTY ((if_marked ("type_hash_marked_p"), param_is (struct type_hash)))
htab_t type_hash_table;
static void set_type_quals (tree, int);
static int type_hash_eq (const void *, const void *);
static hashval_t type_hash_hash (const void *);
static void print_type_hash_statistics (void);
static void finish_vector_type (tree);
static int type_hash_marked_p (const void *);
tree global_trees[TI_MAX];
tree integer_types[itk_none];
/* Init tree.c. */
void
init_ttree (void)
{
/* Initialize the hash table of types. */
type_hash_table = htab_create_ggc (TYPE_HASH_INITIAL_SIZE, type_hash_hash,
type_hash_eq, 0);
}
/* The name of the object as the assembler will see it (but before any
translations made by ASM_OUTPUT_LABELREF). Often this is the same
as DECL_NAME. It is an IDENTIFIER_NODE. */
tree
decl_assembler_name (tree decl)
{
if (!DECL_ASSEMBLER_NAME_SET_P (decl))
(*lang_hooks.set_decl_assembler_name) (decl);
return DECL_CHECK (decl)->decl.assembler_name;
}
/* Compute the number of bytes occupied by 'node'. This routine only
looks at TREE_CODE and, if the code is TREE_VEC, TREE_VEC_LENGTH. */
size_t
tree_size (tree node)
{
enum tree_code code = TREE_CODE (node);
switch (TREE_CODE_CLASS (code))
{
case 'd': /* A decl node */
return sizeof (struct tree_decl);
case 't': /* a type node */
return sizeof (struct tree_type);
case 'b': /* a lexical block node */
return sizeof (struct tree_block);
case 'r': /* a reference */
case 'e': /* an expression */
case 's': /* an expression with side effects */
case '<': /* a comparison expression */
case '1': /* a unary arithmetic expression */
case '2': /* a binary arithmetic expression */
return (sizeof (struct tree_exp)
+ TREE_CODE_LENGTH (code) * sizeof (char *) - sizeof (char *));
case 'c': /* a constant */
switch (code)
{
case INTEGER_CST: return sizeof (struct tree_int_cst);
case REAL_CST: return sizeof (struct tree_real_cst);
case COMPLEX_CST: return sizeof (struct tree_complex);
case VECTOR_CST: return sizeof (struct tree_vector);
case STRING_CST: return sizeof (struct tree_string);
default:
return (*lang_hooks.tree_size) (code);
}
case 'x': /* something random, like an identifier. */
switch (code)
{
case IDENTIFIER_NODE: return lang_hooks.identifier_size;
case TREE_LIST: return sizeof (struct tree_list);
case TREE_VEC: return (sizeof (struct tree_vec)
+ TREE_VEC_LENGTH(node) * sizeof(char *)
- sizeof (char *));
case ERROR_MARK:
case PLACEHOLDER_EXPR: return sizeof (struct tree_common);
default:
return (*lang_hooks.tree_size) (code);
}
default:
abort ();
}
}
/* Return a newly allocated node of code CODE.
For decl and type nodes, some other fields are initialized.
The rest of the node is initialized to zero.
Achoo! I got a code in the node. */
tree
make_node (enum tree_code code)
{
tree t;
int type = TREE_CODE_CLASS (code);
size_t length;
#ifdef GATHER_STATISTICS
tree_node_kind kind;
#endif
struct tree_common ttmp;
/* We can't allocate a TREE_VEC without knowing how many elements
it will have. */
if (code == TREE_VEC)
abort ();
TREE_SET_CODE ((tree)&ttmp, code);
length = tree_size ((tree)&ttmp);
#ifdef GATHER_STATISTICS
switch (type)
{
case 'd': /* A decl node */
kind = d_kind;
break;
case 't': /* a type node */
kind = t_kind;
break;
case 'b': /* a lexical block */
kind = b_kind;
break;
case 's': /* an expression with side effects */
kind = s_kind;
break;
case 'r': /* a reference */
kind = r_kind;
break;
case 'e': /* an expression */
case '<': /* a comparison expression */
case '1': /* a unary arithmetic expression */
case '2': /* a binary arithmetic expression */
kind = e_kind;
break;
case 'c': /* a constant */
kind = c_kind;
break;
case 'x': /* something random, like an identifier. */
if (code == IDENTIFIER_NODE)
kind = id_kind;
else if (code == TREE_VEC)
kind = vec_kind;
else
kind = x_kind;
break;
default:
abort ();
}
tree_node_counts[(int) kind]++;
tree_node_sizes[(int) kind] += length;
#endif
t = ggc_alloc_tree (length);
memset (t, 0, length);
TREE_SET_CODE (t, code);
switch (type)
{
case 's':
TREE_SIDE_EFFECTS (t) = 1;
break;
case 'd':
if (code != FUNCTION_DECL)
DECL_ALIGN (t) = 1;
DECL_USER_ALIGN (t) = 0;
DECL_IN_SYSTEM_HEADER (t) = in_system_header;
DECL_SOURCE_LOCATION (t) = input_location;
DECL_UID (t) = next_decl_uid++;
/* We have not yet computed the alias set for this declaration. */
DECL_POINTER_ALIAS_SET (t) = -1;
break;
case 't':
TYPE_UID (t) = next_type_uid++;
TYPE_ALIGN (t) = char_type_node ? TYPE_ALIGN (char_type_node) : 0;
TYPE_USER_ALIGN (t) = 0;
TYPE_MAIN_VARIANT (t) = t;
/* Default to no attributes for type, but let target change that. */
TYPE_ATTRIBUTES (t) = NULL_TREE;
(*targetm.set_default_type_attributes) (t);
/* We have not yet computed the alias set for this type. */
TYPE_ALIAS_SET (t) = -1;
break;
case 'c':
TREE_CONSTANT (t) = 1;
break;
case 'e':
switch (code)
{
case INIT_EXPR:
case MODIFY_EXPR:
case VA_ARG_EXPR:
case RTL_EXPR:
case PREDECREMENT_EXPR:
case PREINCREMENT_EXPR:
case POSTDECREMENT_EXPR:
case POSTINCREMENT_EXPR:
/* All of these have side-effects, no matter what their
operands are. */
TREE_SIDE_EFFECTS (t) = 1;
break;
default:
break;
}
break;
}
return t;
}
/* Return a new node with the same contents as NODE except that its
TREE_CHAIN is zero and it has a fresh uid. */
tree
copy_node (tree node)
{
tree t;
enum tree_code code = TREE_CODE (node);
size_t length;
length = tree_size (node);
t = ggc_alloc_tree (length);
memcpy (t, node, length);
TREE_CHAIN (t) = 0;
TREE_ASM_WRITTEN (t) = 0;
if (TREE_CODE_CLASS (code) == 'd')
DECL_UID (t) = next_decl_uid++;
else if (TREE_CODE_CLASS (code) == 't')
{
TYPE_UID (t) = next_type_uid++;
/* The following is so that the debug code for
the copy is different from the original type.
The two statements usually duplicate each other
(because they clear fields of the same union),
but the optimizer should catch that. */
TYPE_SYMTAB_POINTER (t) = 0;
TYPE_SYMTAB_ADDRESS (t) = 0;
}
return t;
}
/* Return a copy of a chain of nodes, chained through the TREE_CHAIN field.
For example, this can copy a list made of TREE_LIST nodes. */
tree
copy_list (tree list)
{
tree head;
tree prev, next;
if (list == 0)
return 0;
head = prev = copy_node (list);
next = TREE_CHAIN (list);
while (next)
{
TREE_CHAIN (prev) = copy_node (next);
prev = TREE_CHAIN (prev);
next = TREE_CHAIN (next);
}
return head;
}
/* Return a newly constructed INTEGER_CST node whose constant value
is specified by the two ints LOW and HI.
The TREE_TYPE is set to `int'.
This function should be used via the `build_int_2' macro. */
tree
build_int_2_wide (unsigned HOST_WIDE_INT low, HOST_WIDE_INT hi)
{
tree t = make_node (INTEGER_CST);
TREE_INT_CST_LOW (t) = low;
TREE_INT_CST_HIGH (t) = hi;
TREE_TYPE (t) = integer_type_node;
return t;
}
/* Return a new VECTOR_CST node whose type is TYPE and whose values
are in a list pointed by VALS. */
tree
build_vector (tree type, tree vals)
{
tree v = make_node (VECTOR_CST);
int over1 = 0, over2 = 0;
tree link;
TREE_VECTOR_CST_ELTS (v) = vals;
TREE_TYPE (v) = type;
/* Iterate through elements and check for overflow. */
for (link = vals; link; link = TREE_CHAIN (link))
{
tree value = TREE_VALUE (link);
over1 |= TREE_OVERFLOW (value);
over2 |= TREE_CONSTANT_OVERFLOW (value);
}
TREE_OVERFLOW (v) = over1;
TREE_CONSTANT_OVERFLOW (v) = over2;
return v;
}
/* Return a new CONSTRUCTOR node whose type is TYPE and whose values
are in a list pointed to by VALS. */
tree
build_constructor (tree type, tree vals)
{
tree c = make_node (CONSTRUCTOR);
TREE_TYPE (c) = type;
CONSTRUCTOR_ELTS (c) = vals;
/* ??? May not be necessary. Mirrors what build does. */
if (vals)
{
TREE_SIDE_EFFECTS (c) = TREE_SIDE_EFFECTS (vals);
TREE_READONLY (c) = TREE_READONLY (vals);
TREE_CONSTANT (c) = TREE_CONSTANT (vals);
}
else
TREE_CONSTANT (c) = 0; /* safe side */
return c;
}
/* Return a new REAL_CST node whose type is TYPE and value is D. */
tree
build_real (tree type, REAL_VALUE_TYPE d)
{
tree v;
REAL_VALUE_TYPE *dp;
int overflow = 0;
/* ??? Used to check for overflow here via CHECK_FLOAT_TYPE.
Consider doing it via real_convert now. */
v = make_node (REAL_CST);
dp = ggc_alloc (sizeof (REAL_VALUE_TYPE));
memcpy (dp, &d, sizeof (REAL_VALUE_TYPE));
TREE_TYPE (v) = type;
TREE_REAL_CST_PTR (v) = dp;
TREE_OVERFLOW (v) = TREE_CONSTANT_OVERFLOW (v) = overflow;
return v;
}
/* Return a new REAL_CST node whose type is TYPE
and whose value is the integer value of the INTEGER_CST node I. */
REAL_VALUE_TYPE
real_value_from_int_cst (tree type, tree i)
{
REAL_VALUE_TYPE d;
/* Clear all bits of the real value type so that we can later do
bitwise comparisons to see if two values are the same. */
memset (&d, 0, sizeof d);
real_from_integer (&d, type ? TYPE_MODE (type) : VOIDmode,
TREE_INT_CST_LOW (i), TREE_INT_CST_HIGH (i),
TREE_UNSIGNED (TREE_TYPE (i)));
return d;
}
/* Given a tree representing an integer constant I, return a tree
representing the same value as a floating-point constant of type TYPE. */
tree
build_real_from_int_cst (tree type, tree i)
{
tree v;
int overflow = TREE_OVERFLOW (i);
v = build_real (type, real_value_from_int_cst (type, i));
TREE_OVERFLOW (v) |= overflow;
TREE_CONSTANT_OVERFLOW (v) |= overflow;
return v;
}
/* Return a newly constructed STRING_CST node whose value is
the LEN characters at STR.
The TREE_TYPE is not initialized. */
tree
build_string (int len, const char *str)
{
tree s = make_node (STRING_CST);
TREE_STRING_LENGTH (s) = len;
TREE_STRING_POINTER (s) = ggc_alloc_string (str, len);
return s;
}
/* Return a newly constructed COMPLEX_CST node whose value is
specified by the real and imaginary parts REAL and IMAG.
Both REAL and IMAG should be constant nodes. TYPE, if specified,
will be the type of the COMPLEX_CST; otherwise a new type will be made. */
tree
build_complex (tree type, tree real, tree imag)
{
tree t = make_node (COMPLEX_CST);
TREE_REALPART (t) = real;
TREE_IMAGPART (t) = imag;
TREE_TYPE (t) = type ? type : build_complex_type (TREE_TYPE (real));
TREE_OVERFLOW (t) = TREE_OVERFLOW (real) | TREE_OVERFLOW (imag);
TREE_CONSTANT_OVERFLOW (t)
= TREE_CONSTANT_OVERFLOW (real) | TREE_CONSTANT_OVERFLOW (imag);
return t;
}
/* Build a newly constructed TREE_VEC node of length LEN. */
tree
make_tree_vec (int len)
{
tree t;
int length = (len - 1) * sizeof (tree) + sizeof (struct tree_vec);
#ifdef GATHER_STATISTICS
tree_node_counts[(int) vec_kind]++;
tree_node_sizes[(int) vec_kind] += length;
#endif
t = ggc_alloc_tree (length);
memset (t, 0, length);
TREE_SET_CODE (t, TREE_VEC);
TREE_VEC_LENGTH (t) = len;
return t;
}
/* Return 1 if EXPR is the integer constant zero or a complex constant
of zero. */
int
integer_zerop (tree expr)
{
STRIP_NOPS (expr);
return ((TREE_CODE (expr) == INTEGER_CST
&& ! TREE_CONSTANT_OVERFLOW (expr)
&& TREE_INT_CST_LOW (expr) == 0
&& TREE_INT_CST_HIGH (expr) == 0)
|| (TREE_CODE (expr) == COMPLEX_CST
&& integer_zerop (TREE_REALPART (expr))
&& integer_zerop (TREE_IMAGPART (expr))));
}
/* Return 1 if EXPR is the integer constant one or the corresponding
complex constant. */
int
integer_onep (tree expr)
{
STRIP_NOPS (expr);
return ((TREE_CODE (expr) == INTEGER_CST
&& ! TREE_CONSTANT_OVERFLOW (expr)
&& TREE_INT_CST_LOW (expr) == 1
&& TREE_INT_CST_HIGH (expr) == 0)
|| (TREE_CODE (expr) == COMPLEX_CST
&& integer_onep (TREE_REALPART (expr))
&& integer_zerop (TREE_IMAGPART (expr))));
}
/* Return 1 if EXPR is an integer containing all 1's in as much precision as
it contains. Likewise for the corresponding complex constant. */
int
integer_all_onesp (tree expr)
{
int prec;
int uns;
STRIP_NOPS (expr);
if (TREE_CODE (expr) == COMPLEX_CST
&& integer_all_onesp (TREE_REALPART (expr))
&& integer_zerop (TREE_IMAGPART (expr)))
return 1;
else if (TREE_CODE (expr) != INTEGER_CST
|| TREE_CONSTANT_OVERFLOW (expr))
return 0;
uns = TREE_UNSIGNED (TREE_TYPE (expr));
if (!uns)
return (TREE_INT_CST_LOW (expr) == ~(unsigned HOST_WIDE_INT) 0
&& TREE_INT_CST_HIGH (expr) == -1);
/* Note that using TYPE_PRECISION here is wrong. We care about the
actual bits, not the (arbitrary) range of the type. */
prec = GET_MODE_BITSIZE (TYPE_MODE (TREE_TYPE (expr)));
if (prec >= HOST_BITS_PER_WIDE_INT)
{
HOST_WIDE_INT high_value;
int shift_amount;
shift_amount = prec - HOST_BITS_PER_WIDE_INT;
if (shift_amount > HOST_BITS_PER_WIDE_INT)
/* Can not handle precisions greater than twice the host int size. */
abort ();
else if (shift_amount == HOST_BITS_PER_WIDE_INT)
/* Shifting by the host word size is undefined according to the ANSI
standard, so we must handle this as a special case. */
high_value = -1;
else
high_value = ((HOST_WIDE_INT) 1 << shift_amount) - 1;
return (TREE_INT_CST_LOW (expr) == ~(unsigned HOST_WIDE_INT) 0
&& TREE_INT_CST_HIGH (expr) == high_value);
}
else
return TREE_INT_CST_LOW (expr) == ((unsigned HOST_WIDE_INT) 1 << prec) - 1;
}
/* Return 1 if EXPR is an integer constant that is a power of 2 (i.e., has only
one bit on). */
int
integer_pow2p (tree expr)
{
int prec;
HOST_WIDE_INT high, low;
STRIP_NOPS (expr);
if (TREE_CODE (expr) == COMPLEX_CST
&& integer_pow2p (TREE_REALPART (expr))
&& integer_zerop (TREE_IMAGPART (expr)))
return 1;
if (TREE_CODE (expr) != INTEGER_CST || TREE_CONSTANT_OVERFLOW (expr))
return 0;
prec = (POINTER_TYPE_P (TREE_TYPE (expr))
? POINTER_SIZE : TYPE_PRECISION (TREE_TYPE (expr)));
high = TREE_INT_CST_HIGH (expr);
low = TREE_INT_CST_LOW (expr);
/* First clear all bits that are beyond the type's precision in case
we've been sign extended. */
if (prec == 2 * HOST_BITS_PER_WIDE_INT)
;
else if (prec > HOST_BITS_PER_WIDE_INT)
high &= ~((HOST_WIDE_INT) (-1) << (prec - HOST_BITS_PER_WIDE_INT));
else
{
high = 0;
if (prec < HOST_BITS_PER_WIDE_INT)
low &= ~((HOST_WIDE_INT) (-1) << prec);
}
if (high == 0 && low == 0)
return 0;
return ((high == 0 && (low & (low - 1)) == 0)
|| (low == 0 && (high & (high - 1)) == 0));
}
/* Return 1 if EXPR is an integer constant other than zero or a
complex constant other than zero. */
int
integer_nonzerop (tree expr)
{
STRIP_NOPS (expr);
return ((TREE_CODE (expr) == INTEGER_CST
&& ! TREE_CONSTANT_OVERFLOW (expr)
&& (TREE_INT_CST_LOW (expr) != 0
|| TREE_INT_CST_HIGH (expr) != 0))
|| (TREE_CODE (expr) == COMPLEX_CST
&& (integer_nonzerop (TREE_REALPART (expr))
|| integer_nonzerop (TREE_IMAGPART (expr)))));
}
/* Return the power of two represented by a tree node known to be a
power of two. */
int
tree_log2 (tree expr)
{
int prec;
HOST_WIDE_INT high, low;
STRIP_NOPS (expr);
if (TREE_CODE (expr) == COMPLEX_CST)
return tree_log2 (TREE_REALPART (expr));
prec = (POINTER_TYPE_P (TREE_TYPE (expr))
? POINTER_SIZE : TYPE_PRECISION (TREE_TYPE (expr)));
high = TREE_INT_CST_HIGH (expr);
low = TREE_INT_CST_LOW (expr);
/* First clear all bits that are beyond the type's precision in case
we've been sign extended. */
if (prec == 2 * HOST_BITS_PER_WIDE_INT)
;
else if (prec > HOST_BITS_PER_WIDE_INT)
high &= ~((HOST_WIDE_INT) (-1) << (prec - HOST_BITS_PER_WIDE_INT));
else
{
high = 0;
if (prec < HOST_BITS_PER_WIDE_INT)
low &= ~((HOST_WIDE_INT) (-1) << prec);
}
return (high != 0 ? HOST_BITS_PER_WIDE_INT + exact_log2 (high)
: exact_log2 (low));
}
/* Similar, but return the largest integer Y such that 2 ** Y is less
than or equal to EXPR. */
int
tree_floor_log2 (tree expr)
{
int prec;
HOST_WIDE_INT high, low;
STRIP_NOPS (expr);
if (TREE_CODE (expr) == COMPLEX_CST)
return tree_log2 (TREE_REALPART (expr));
prec = (POINTER_TYPE_P (TREE_TYPE (expr))
? POINTER_SIZE : TYPE_PRECISION (TREE_TYPE (expr)));
high = TREE_INT_CST_HIGH (expr);
low = TREE_INT_CST_LOW (expr);
/* First clear all bits that are beyond the type's precision in case
we've been sign extended. Ignore if type's precision hasn't been set
since what we are doing is setting it. */
if (prec == 2 * HOST_BITS_PER_WIDE_INT || prec == 0)
;
else if (prec > HOST_BITS_PER_WIDE_INT)
high &= ~((HOST_WIDE_INT) (-1) << (prec - HOST_BITS_PER_WIDE_INT));
else
{
high = 0;
if (prec < HOST_BITS_PER_WIDE_INT)
low &= ~((HOST_WIDE_INT) (-1) << prec);
}
return (high != 0 ? HOST_BITS_PER_WIDE_INT + floor_log2 (high)
: floor_log2 (low));
}
/* Return 1 if EXPR is the real constant zero. */
int
real_zerop (tree expr)
{
STRIP_NOPS (expr);
return ((TREE_CODE (expr) == REAL_CST
&& ! TREE_CONSTANT_OVERFLOW (expr)
&& REAL_VALUES_EQUAL (TREE_REAL_CST (expr), dconst0))
|| (TREE_CODE (expr) == COMPLEX_CST
&& real_zerop (TREE_REALPART (expr))
&& real_zerop (TREE_IMAGPART (expr))));
}
/* Return 1 if EXPR is the real constant one in real or complex form. */
int
real_onep (tree expr)
{
STRIP_NOPS (expr);
return ((TREE_CODE (expr) == REAL_CST
&& ! TREE_CONSTANT_OVERFLOW (expr)
&& REAL_VALUES_EQUAL (TREE_REAL_CST (expr), dconst1))
|| (TREE_CODE (expr) == COMPLEX_CST
&& real_onep (TREE_REALPART (expr))
&& real_zerop (TREE_IMAGPART (expr))));
}
/* Return 1 if EXPR is the real constant two. */
int
real_twop (tree expr)
{
STRIP_NOPS (expr);
return ((TREE_CODE (expr) == REAL_CST
&& ! TREE_CONSTANT_OVERFLOW (expr)
&& REAL_VALUES_EQUAL (TREE_REAL_CST (expr), dconst2))
|| (TREE_CODE (expr) == COMPLEX_CST
&& real_twop (TREE_REALPART (expr))
&& real_zerop (TREE_IMAGPART (expr))));
}
/* Return 1 if EXPR is the real constant minus one. */
int
real_minus_onep (tree expr)
{
STRIP_NOPS (expr);
return ((TREE_CODE (expr) == REAL_CST
&& ! TREE_CONSTANT_OVERFLOW (expr)
&& REAL_VALUES_EQUAL (TREE_REAL_CST (expr), dconstm1))
|| (TREE_CODE (expr) == COMPLEX_CST
&& real_minus_onep (TREE_REALPART (expr))
&& real_zerop (TREE_IMAGPART (expr))));
}
/* Nonzero if EXP is a constant or a cast of a constant. */
int
really_constant_p (tree exp)
{
/* This is not quite the same as STRIP_NOPS. It does more. */
while (TREE_CODE (exp) == NOP_EXPR
|| TREE_CODE (exp) == CONVERT_EXPR
|| TREE_CODE (exp) == NON_LVALUE_EXPR)
exp = TREE_OPERAND (exp, 0);
return TREE_CONSTANT (exp);
}
/* Return first list element whose TREE_VALUE is ELEM.
Return 0 if ELEM is not in LIST. */
tree
value_member (tree elem, tree list)
{
while (list)
{
if (elem == TREE_VALUE (list))
return list;
list = TREE_CHAIN (list);
}
return NULL_TREE;
}
/* Return first list element whose TREE_PURPOSE is ELEM.
Return 0 if ELEM is not in LIST. */
tree
purpose_member (tree elem, tree list)
{
while (list)
{
if (elem == TREE_PURPOSE (list))
return list;
list = TREE_CHAIN (list);
}
return NULL_TREE;
}
/* Return first list element whose BINFO_TYPE is ELEM.
Return 0 if ELEM is not in LIST. */
tree
binfo_member (tree elem, tree list)
{
while (list)
{
if (elem == BINFO_TYPE (list))
return list;
list = TREE_CHAIN (list);
}
return NULL_TREE;
}
/* Return nonzero if ELEM is part of the chain CHAIN. */
int
chain_member (tree elem, tree chain)
{
while (chain)
{
if (elem == chain)
return 1;
chain = TREE_CHAIN (chain);
}
return 0;
}
/* Return the length of a chain of nodes chained through TREE_CHAIN.
We expect a null pointer to mark the end of the chain.
This is the Lisp primitive `length'. */
int
list_length (tree t)
{
tree tail;
int len = 0;
for (tail = t; tail; tail = TREE_CHAIN (tail))
len++;
return len;
}
/* Returns the number of FIELD_DECLs in TYPE. */
int
fields_length (tree type)
{
tree t = TYPE_FIELDS (type);
int count = 0;
for (; t; t = TREE_CHAIN (t))
if (TREE_CODE (t) == FIELD_DECL)
++count;
return count;
}
/* Concatenate two chains of nodes (chained through TREE_CHAIN)
by modifying the last node in chain 1 to point to chain 2.
This is the Lisp primitive `nconc'. */
tree
chainon (tree op1, tree op2)
{
tree t1;
if (!op1)
return op2;
if (!op2)
return op1;
for (t1 = op1; TREE_CHAIN (t1); t1 = TREE_CHAIN (t1))
continue;
TREE_CHAIN (t1) = op2;
#ifdef ENABLE_TREE_CHECKING
{
tree t2;
for (t2 = op2; t2; t2 = TREE_CHAIN (t2))
if (t2 == t1)
abort (); /* Circularity created. */
}
#endif
return op1;
}
/* Return the last node in a chain of nodes (chained through TREE_CHAIN). */
tree
tree_last (tree chain)
{
tree next;
if (chain)
while ((next = TREE_CHAIN (chain)))
chain = next;
return chain;
}
/* Reverse the order of elements in the chain T,
and return the new head of the chain (old last element). */
tree
nreverse (tree t)
{
tree prev = 0, decl, next;
for (decl = t; decl; decl = next)
{
next = TREE_CHAIN (decl);
TREE_CHAIN (decl) = prev;
prev = decl;
}
return prev;
}
/* Return a newly created TREE_LIST node whose
purpose and value fields are PARM and VALUE. */
tree
build_tree_list (tree parm, tree value)
{
tree t = make_node (TREE_LIST);
TREE_PURPOSE (t) = parm;
TREE_VALUE (t) = value;
return t;
}
/* Return a newly created TREE_LIST node whose
purpose and value fields are PURPOSE and VALUE
and whose TREE_CHAIN is CHAIN. */
tree
tree_cons (tree purpose, tree value, tree chain)
{
tree node;
node = ggc_alloc_tree (sizeof (struct tree_list));
memset (node, 0, sizeof (struct tree_common));
#ifdef GATHER_STATISTICS
tree_node_counts[(int) x_kind]++;
tree_node_sizes[(int) x_kind] += sizeof (struct tree_list);
#endif
TREE_SET_CODE (node, TREE_LIST);
TREE_CHAIN (node) = chain;
TREE_PURPOSE (node) = purpose;
TREE_VALUE (node) = value;
return node;
}
/* Return the first expression in a sequence of COMPOUND_EXPRs. */
tree
expr_first (tree expr)
{
if (expr == NULL_TREE)
return expr;
while (TREE_CODE (expr) == COMPOUND_EXPR)
expr = TREE_OPERAND (expr, 0);
return expr;
}
/* Return the last expression in a sequence of COMPOUND_EXPRs. */
tree
expr_last (tree expr)
{
if (expr == NULL_TREE)
return expr;
while (TREE_CODE (expr) == COMPOUND_EXPR)
expr = TREE_OPERAND (expr, 1);
return expr;
}
/* Return the number of subexpressions in a sequence of COMPOUND_EXPRs. */
int
expr_length (tree expr)
{
int len = 0;
if (expr == NULL_TREE)
return 0;
for (; TREE_CODE (expr) == COMPOUND_EXPR; expr = TREE_OPERAND (expr, 1))
len += expr_length (TREE_OPERAND (expr, 0));
++len;
return len;
}
/* Return the size nominally occupied by an object of type TYPE
when it resides in memory. The value is measured in units of bytes,
and its data type is that normally used for type sizes
(which is the first type created by make_signed_type or
make_unsigned_type). */
tree
size_in_bytes (tree type)
{
tree t;
if (type == error_mark_node)
return integer_zero_node;
type = TYPE_MAIN_VARIANT (type);
t = TYPE_SIZE_UNIT (type);
if (t == 0)
{
(*lang_hooks.types.incomplete_type_error) (NULL_TREE, type);
return size_zero_node;
}
if (TREE_CODE (t) == INTEGER_CST)
force_fit_type (t, 0);
return t;
}
/* Return the size of TYPE (in bytes) as a wide integer
or return -1 if the size can vary or is larger than an integer. */
HOST_WIDE_INT
int_size_in_bytes (tree type)
{
tree t;
if (type == error_mark_node)
return 0;
type = TYPE_MAIN_VARIANT (type);
t = TYPE_SIZE_UNIT (type);
if (t == 0
|| TREE_CODE (t) != INTEGER_CST
|| TREE_OVERFLOW (t)
|| TREE_INT_CST_HIGH (t) != 0
/* If the result would appear negative, it's too big to represent. */
|| (HOST_WIDE_INT) TREE_INT_CST_LOW (t) < 0)
return -1;
return TREE_INT_CST_LOW (t);
}
/* Return the bit position of FIELD, in bits from the start of the record.
This is a tree of type bitsizetype. */
tree
bit_position (tree field)
{
return bit_from_pos (DECL_FIELD_OFFSET (field),
DECL_FIELD_BIT_OFFSET (field));
}
/* Likewise, but return as an integer. Abort if it cannot be represented
in that way (since it could be a signed value, we don't have the option
of returning -1 like int_size_in_byte can. */
HOST_WIDE_INT
int_bit_position (tree field)
{
return tree_low_cst (bit_position (field), 0);
}
/* Return the byte position of FIELD, in bytes from the start of the record.
This is a tree of type sizetype. */
tree
byte_position (tree field)
{
return byte_from_pos (DECL_FIELD_OFFSET (field),
DECL_FIELD_BIT_OFFSET (field));
}
/* Likewise, but return as an integer. Abort if it cannot be represented
in that way (since it could be a signed value, we don't have the option
of returning -1 like int_size_in_byte can. */
HOST_WIDE_INT
int_byte_position (tree field)
{
return tree_low_cst (byte_position (field), 0);
}
/* Return the strictest alignment, in bits, that T is known to have. */
unsigned int
expr_align (tree t)
{
unsigned int align0, align1;
switch (TREE_CODE (t))
{
case NOP_EXPR: case CONVERT_EXPR: case NON_LVALUE_EXPR:
/* If we have conversions, we know that the alignment of the
object must meet each of the alignments of the types. */
align0 = expr_align (TREE_OPERAND (t, 0));
align1 = TYPE_ALIGN (TREE_TYPE (t));
return MAX (align0, align1);
case SAVE_EXPR: case COMPOUND_EXPR: case MODIFY_EXPR:
case INIT_EXPR: case TARGET_EXPR: case WITH_CLEANUP_EXPR:
case WITH_RECORD_EXPR: case CLEANUP_POINT_EXPR: case UNSAVE_EXPR:
/* These don't change the alignment of an object. */
return expr_align (TREE_OPERAND (t, 0));
case COND_EXPR:
/* The best we can do is say that the alignment is the least aligned
of the two arms. */
align0 = expr_align (TREE_OPERAND (t, 1));
align1 = expr_align (TREE_OPERAND (t, 2));
return MIN (align0, align1);
case LABEL_DECL: case CONST_DECL:
case VAR_DECL: case PARM_DECL: case RESULT_DECL:
if (DECL_ALIGN (t) != 0)
return DECL_ALIGN (t);
break;
case FUNCTION_DECL:
return FUNCTION_BOUNDARY;
default:
break;
}
/* Otherwise take the alignment from that of the type. */
return TYPE_ALIGN (TREE_TYPE (t));
}
/* Return, as a tree node, the number of elements for TYPE (which is an
ARRAY_TYPE) minus one. This counts only elements of the top array. */
tree
array_type_nelts (tree type)
{
tree index_type, min, max;
/* If they did it with unspecified bounds, then we should have already
given an error about it before we got here. */
if (! TYPE_DOMAIN (type))
return error_mark_node;
index_type = TYPE_DOMAIN (type);
min = TYPE_MIN_VALUE (index_type);
max = TYPE_MAX_VALUE (index_type);
return (integer_zerop (min)
? max
: fold (build (MINUS_EXPR, TREE_TYPE (max), max, min)));
}
/* Return nonzero if arg is static -- a reference to an object in
static storage. This is not the same as the C meaning of `static'. */
int
staticp (tree arg)
{
switch (TREE_CODE (arg))
{
case FUNCTION_DECL:
/* Nested functions aren't static, since taking their address
involves a trampoline. */
return ((decl_function_context (arg) == 0 || DECL_NO_STATIC_CHAIN (arg))
&& ! DECL_NON_ADDR_CONST_P (arg));
case VAR_DECL:
return ((TREE_STATIC (arg) || DECL_EXTERNAL (arg))
&& ! DECL_THREAD_LOCAL (arg)
&& ! DECL_NON_ADDR_CONST_P (arg));
case CONSTRUCTOR:
return TREE_STATIC (arg);
case LABEL_DECL:
case STRING_CST:
return 1;
/* If we are referencing a bitfield, we can't evaluate an
ADDR_EXPR at compile time and so it isn't a constant. */
case COMPONENT_REF:
return (! DECL_BIT_FIELD (TREE_OPERAND (arg, 1))
&& staticp (TREE_OPERAND (arg, 0)));
case BIT_FIELD_REF:
return 0;
#if 0
/* This case is technically correct, but results in setting
TREE_CONSTANT on ADDR_EXPRs that cannot be evaluated at
compile time. */
case INDIRECT_REF:
return TREE_CONSTANT (TREE_OPERAND (arg, 0));
#endif
case ARRAY_REF:
case ARRAY_RANGE_REF:
if (TREE_CODE (TYPE_SIZE (TREE_TYPE (arg))) == INTEGER_CST
&& TREE_CODE (TREE_OPERAND (arg, 1)) == INTEGER_CST)
return staticp (TREE_OPERAND (arg, 0));
default:
if ((unsigned int) TREE_CODE (arg)
>= (unsigned int) LAST_AND_UNUSED_TREE_CODE)
return (*lang_hooks.staticp) (arg);
else
return 0;
}
}
/* Wrap a SAVE_EXPR around EXPR, if appropriate.
Do this to any expression which may be used in more than one place,
but must be evaluated only once.
Normally, expand_expr would reevaluate the expression each time.
Calling save_expr produces something that is evaluated and recorded
the first time expand_expr is called on it. Subsequent calls to
expand_expr just reuse the recorded value.
The call to expand_expr that generates code that actually computes
the value is the first call *at compile time*. Subsequent calls
*at compile time* generate code to use the saved value.
This produces correct result provided that *at run time* control
always flows through the insns made by the first expand_expr
before reaching the other places where the save_expr was evaluated.
You, the caller of save_expr, must make sure this is so.
Constants, and certain read-only nodes, are returned with no
SAVE_EXPR because that is safe. Expressions containing placeholders
are not touched; see tree.def for an explanation of what these
are used for. */
tree
save_expr (tree expr)
{
tree t = fold (expr);
tree inner;
/* If the tree evaluates to a constant, then we don't want to hide that
fact (i.e. this allows further folding, and direct checks for constants).
However, a read-only object that has side effects cannot be bypassed.
Since it is no problem to reevaluate literals, we just return the
literal node. */
inner = skip_simple_arithmetic (t);
if (TREE_CONSTANT (inner)
|| (TREE_READONLY (inner) && ! TREE_SIDE_EFFECTS (inner))
|| TREE_CODE (inner) == SAVE_EXPR
|| TREE_CODE (inner) == ERROR_MARK)
return t;
/* If INNER contains a PLACEHOLDER_EXPR, we must evaluate it each time, since
it means that the size or offset of some field of an object depends on
the value within another field.
Note that it must not be the case that T contains both a PLACEHOLDER_EXPR
and some variable since it would then need to be both evaluated once and
evaluated more than once. Front-ends must assure this case cannot
happen by surrounding any such subexpressions in their own SAVE_EXPR
and forcing evaluation at the proper time. */
if (contains_placeholder_p (inner))
return t;
t = build (SAVE_EXPR, TREE_TYPE (expr), t, current_function_decl, NULL_TREE);
/* This expression might be placed ahead of a jump to ensure that the
value was computed on both sides of the jump. So make sure it isn't
eliminated as dead. */
TREE_SIDE_EFFECTS (t) = 1;
TREE_READONLY (t) = 1;
return t;
}
/* Look inside EXPR and into any simple arithmetic operations. Return
the innermost non-arithmetic node. */
tree
skip_simple_arithmetic (tree expr)
{
tree inner;
/* We don't care about whether this can be used as an lvalue in this
context. */
while (TREE_CODE (expr) == NON_LVALUE_EXPR)
expr = TREE_OPERAND (expr, 0);
/* If we have simple operations applied to a SAVE_EXPR or to a SAVE_EXPR and
a constant, it will be more efficient to not make another SAVE_EXPR since
it will allow better simplification and GCSE will be able to merge the
computations if they actually occur. */
inner = expr;
while (1)
{
if (TREE_CODE_CLASS (TREE_CODE (inner)) == '1')
inner = TREE_OPERAND (inner, 0);
else if (TREE_CODE_CLASS (TREE_CODE (inner)) == '2')
{
if (TREE_CONSTANT (TREE_OPERAND (inner, 1)))
inner = TREE_OPERAND (inner, 0);
else if (TREE_CONSTANT (TREE_OPERAND (inner, 0)))
inner = TREE_OPERAND (inner, 1);
else
break;
}
else
break;
}
return inner;
}
/* Return TRUE if EXPR is a SAVE_EXPR or wraps simple arithmetic around a
SAVE_EXPR. Return FALSE otherwise. */
bool
saved_expr_p (tree expr)
{
return TREE_CODE (skip_simple_arithmetic (expr)) == SAVE_EXPR;
}
/* Arrange for an expression to be expanded multiple independent
times. This is useful for cleanup actions, as the backend can
expand them multiple times in different places. */
tree
unsave_expr (tree expr)
{
tree t;
/* If this is already protected, no sense in protecting it again. */
if (TREE_CODE (expr) == UNSAVE_EXPR)
return expr;
t = build1 (UNSAVE_EXPR, TREE_TYPE (expr), expr);
TREE_SIDE_EFFECTS (t) = TREE_SIDE_EFFECTS (expr);
return t;
}
/* Returns the index of the first non-tree operand for CODE, or the number
of operands if all are trees. */
int
first_rtl_op (enum tree_code code)
{
switch (code)
{
case SAVE_EXPR:
return 2;
case GOTO_SUBROUTINE_EXPR:
case RTL_EXPR:
return 0;
case WITH_CLEANUP_EXPR:
return 2;
default:
return TREE_CODE_LENGTH (code);
}
}
/* Return which tree structure is used by T. */
enum tree_node_structure_enum
tree_node_structure (tree t)
{
enum tree_code code = TREE_CODE (t);
switch (TREE_CODE_CLASS (code))
{
case 'd': return TS_DECL;
case 't': return TS_TYPE;
case 'b': return TS_BLOCK;
case 'r': case '<': case '1': case '2': case 'e': case 's':
return TS_EXP;
default: /* 'c' and 'x' */
break;
}
switch (code)
{
/* 'c' cases. */
case INTEGER_CST: return TS_INT_CST;
case REAL_CST: return TS_REAL_CST;
case COMPLEX_CST: return TS_COMPLEX;
case VECTOR_CST: return TS_VECTOR;
case STRING_CST: return TS_STRING;
/* 'x' cases. */
case ERROR_MARK: return TS_COMMON;
case IDENTIFIER_NODE: return TS_IDENTIFIER;
case TREE_LIST: return TS_LIST;
case TREE_VEC: return TS_VEC;
case PLACEHOLDER_EXPR: return TS_COMMON;
default:
abort ();
}
}
/* Perform any modifications to EXPR required when it is unsaved. Does
not recurse into EXPR's subtrees. */
void
unsave_expr_1 (tree expr)
{
switch (TREE_CODE (expr))
{
case SAVE_EXPR:
if (! SAVE_EXPR_PERSISTENT_P (expr))
SAVE_EXPR_RTL (expr) = 0;
break;
case TARGET_EXPR:
/* Don't mess with a TARGET_EXPR that hasn't been expanded.
It's OK for this to happen if it was part of a subtree that
isn't immediately expanded, such as operand 2 of another
TARGET_EXPR. */
if (TREE_OPERAND (expr, 1))
break;
TREE_OPERAND (expr, 1) = TREE_OPERAND (expr, 3);
TREE_OPERAND (expr, 3) = NULL_TREE;
break;
case RTL_EXPR:
/* I don't yet know how to emit a sequence multiple times. */
if (RTL_EXPR_SEQUENCE (expr) != 0)
abort ();
break;
default:
break;
}
}
/* Default lang hook for "unsave_expr_now". */
tree
lhd_unsave_expr_now (tree expr)
{
enum tree_code code;
/* There's nothing to do for NULL_TREE. */
if (expr == 0)
return expr;
unsave_expr_1 (expr);
code = TREE_CODE (expr);
switch (TREE_CODE_CLASS (code))
{
case 'c': /* a constant */
case 't': /* a type node */
case 'd': /* A decl node */
case 'b': /* A block node */
break;
case 'x': /* miscellaneous: e.g., identifier, TREE_LIST or ERROR_MARK. */
if (code == TREE_LIST)
{
lhd_unsave_expr_now (TREE_VALUE (expr));
lhd_unsave_expr_now (TREE_CHAIN (expr));
}
break;
case 'e': /* an expression */
case 'r': /* a reference */
case 's': /* an expression with side effects */
case '<': /* a comparison expression */
case '2': /* a binary arithmetic expression */
case '1': /* a unary arithmetic expression */
{
int i;
for (i = first_rtl_op (code) - 1; i >= 0; i--)
lhd_unsave_expr_now (TREE_OPERAND (expr, i));
}
break;
default:
abort ();
}
return expr;
}
/* Return 0 if it is safe to evaluate EXPR multiple times,
return 1 if it is safe if EXPR is unsaved afterward, or
return 2 if it is completely unsafe.
This assumes that CALL_EXPRs and TARGET_EXPRs are never replicated in
an expression tree, so that it safe to unsave them and the surrounding
context will be correct.
SAVE_EXPRs basically *only* appear replicated in an expression tree,
occasionally across the whole of a function. It is therefore only
safe to unsave a SAVE_EXPR if you know that all occurrences appear
below the UNSAVE_EXPR.
RTL_EXPRs consume their rtl during evaluation. It is therefore
never possible to unsave them. */
int
unsafe_for_reeval (tree expr)
{
int unsafeness = 0;
enum tree_code code;
int i, tmp, tmp2;
tree exp;
int first_rtl;
if (expr == NULL_TREE)
return 1;
code = TREE_CODE (expr);
first_rtl = first_rtl_op (code);
switch (code)
{
case SAVE_EXPR:
case RTL_EXPR:
case TRY_CATCH_EXPR:
return 2;
case TREE_LIST:
for (exp = expr; exp != 0; exp = TREE_CHAIN (exp))
{
tmp = unsafe_for_reeval (TREE_VALUE (exp));
unsafeness = MAX (tmp, unsafeness);
}
return unsafeness;
case CALL_EXPR:
tmp2 = unsafe_for_reeval (TREE_OPERAND (expr, 0));
tmp = unsafe_for_reeval (TREE_OPERAND (expr, 1));
return MAX (MAX (tmp, 1), tmp2);
case TARGET_EXPR:
unsafeness = 1;
break;
case EXIT_BLOCK_EXPR:
/* EXIT_BLOCK_LABELED_BLOCK, a.k.a. TREE_OPERAND (expr, 0), holds
a reference to an ancestor LABELED_BLOCK, so we need to avoid
unbounded recursion in the 'e' traversal code below. */
exp = EXIT_BLOCK_RETURN (expr);
return exp ? unsafe_for_reeval (exp) : 0;
default:
tmp = (*lang_hooks.unsafe_for_reeval) (expr);
if (tmp >= 0)
return tmp;
break;
}
switch (TREE_CODE_CLASS (code))
{
case 'c': /* a constant */
case 't': /* a type node */
case 'x': /* something random, like an identifier or an ERROR_MARK. */
case 'd': /* A decl node */
case 'b': /* A block node */
return 0;
case 'e': /* an expression */
case 'r': /* a reference */
case 's': /* an expression with side effects */
case '<': /* a comparison expression */
case '2': /* a binary arithmetic expression */
case '1': /* a unary arithmetic expression */
for (i = first_rtl - 1; i >= 0; i--)
{
tmp = unsafe_for_reeval (TREE_OPERAND (expr, i));
unsafeness = MAX (tmp, unsafeness);
}
return unsafeness;
default:
return 2;
}
}
/* Return 1 if EXP contains a PLACEHOLDER_EXPR; i.e., if it represents a size
or offset that depends on a field within a record. */
bool
contains_placeholder_p (tree exp)
{
enum tree_code code;
int result;
if (!exp)
return 0;
/* If we have a WITH_RECORD_EXPR, it "cancels" any PLACEHOLDER_EXPR
in it since it is supplying a value for it. */
code = TREE_CODE (exp);
if (code == WITH_RECORD_EXPR)
return 0;
else if (code == PLACEHOLDER_EXPR)
return 1;
switch (TREE_CODE_CLASS (code))
{
case 'r':
/* Don't look at any PLACEHOLDER_EXPRs that might be in index or bit
position computations since they will be converted into a
WITH_RECORD_EXPR involving the reference, which will assume
here will be valid. */
return CONTAINS_PLACEHOLDER_P (TREE_OPERAND (exp, 0));
case 'x':
if (code == TREE_LIST)
return (CONTAINS_PLACEHOLDER_P (TREE_VALUE (exp))
|| CONTAINS_PLACEHOLDER_P (TREE_CHAIN (exp)));
break;
case '1':
case '2': case '<':
case 'e':
switch (code)
{
case COMPOUND_EXPR:
/* Ignoring the first operand isn't quite right, but works best. */
return CONTAINS_PLACEHOLDER_P (TREE_OPERAND (exp, 1));
case RTL_EXPR:
case CONSTRUCTOR:
return 0;
case COND_EXPR:
return (CONTAINS_PLACEHOLDER_P (TREE_OPERAND (exp, 0))
|| CONTAINS_PLACEHOLDER_P (TREE_OPERAND (exp, 1))
|| CONTAINS_PLACEHOLDER_P (TREE_OPERAND (exp, 2)));
case SAVE_EXPR:
/* If we already know this doesn't have a placeholder, don't
check again. */
if (SAVE_EXPR_NOPLACEHOLDER (exp) || SAVE_EXPR_RTL (exp) != 0)
return 0;
SAVE_EXPR_NOPLACEHOLDER (exp) = 1;
result = CONTAINS_PLACEHOLDER_P (TREE_OPERAND (exp, 0));
if (result)
SAVE_EXPR_NOPLACEHOLDER (exp) = 0;
return result;
case CALL_EXPR:
return CONTAINS_PLACEHOLDER_P (TREE_OPERAND (exp, 1));
default:
break;
}
switch (TREE_CODE_LENGTH (code))
{
case 1:
return CONTAINS_PLACEHOLDER_P (TREE_OPERAND (exp, 0));
case 2:
return (CONTAINS_PLACEHOLDER_P (TREE_OPERAND (exp, 0))
|| CONTAINS_PLACEHOLDER_P (TREE_OPERAND (exp, 1)));
default:
return 0;
}
default:
return 0;
}
return 0;
}
/* Return 1 if any part of the computation of TYPE involves a PLACEHOLDER_EXPR.
This includes size, bounds, qualifiers (for QUAL_UNION_TYPE) and field
positions. */
bool
type_contains_placeholder_p (tree type)
{
/* If the size contains a placeholder or the parent type (component type in
the case of arrays) type involves a placeholder, this type does. */
if (CONTAINS_PLACEHOLDER_P (TYPE_SIZE (type))
|| CONTAINS_PLACEHOLDER_P (TYPE_SIZE_UNIT (type))
|| (TREE_TYPE (type) != 0
&& type_contains_placeholder_p (TREE_TYPE (type))))
return 1;
/* Now do type-specific checks. Note that the last part of the check above
greatly limits what we have to do below. */
switch (TREE_CODE (type))
{
case VOID_TYPE:
case COMPLEX_TYPE:
case VECTOR_TYPE:
case ENUMERAL_TYPE:
case BOOLEAN_TYPE:
case CHAR_TYPE:
case POINTER_TYPE:
case OFFSET_TYPE:
case REFERENCE_TYPE:
case METHOD_TYPE:
case FILE_TYPE:
case FUNCTION_TYPE:
return 0;
case INTEGER_TYPE:
case REAL_TYPE:
/* Here we just check the bounds. */
return (CONTAINS_PLACEHOLDER_P (TYPE_MIN_VALUE (type))
|| CONTAINS_PLACEHOLDER_P (TYPE_MAX_VALUE (type)));
case ARRAY_TYPE:
case SET_TYPE:
/* We're already checked the component type (TREE_TYPE), so just check
the index type. */
return type_contains_placeholder_p (TYPE_DOMAIN (type));
case RECORD_TYPE:
case UNION_TYPE:
case QUAL_UNION_TYPE:
{
static tree seen_types = 0;
tree field;
bool ret = 0;
/* We have to be careful here that we don't end up in infinite
recursions due to a field of a type being a pointer to that type
or to a mutually-recursive type. So we store a list of record
types that we've seen and see if this type is in them. To save
memory, we don't use a list for just one type. Here we check
whether we've seen this type before and store it if not. */
if (seen_types == 0)
seen_types = type;
else if (TREE_CODE (seen_types) != TREE_LIST)
{
if (seen_types == type)
return 0;
seen_types = tree_cons (NULL_TREE, type,
build_tree_list (NULL_TREE, seen_types));
}
else
{
if (value_member (type, seen_types) != 0)
return 0;
seen_types = tree_cons (NULL_TREE, type, seen_types);
}
for (field = TYPE_FIELDS (type); field; field = TREE_CHAIN (field))
if (TREE_CODE (field) == FIELD_DECL
&& (CONTAINS_PLACEHOLDER_P (DECL_FIELD_OFFSET (field))
|| (TREE_CODE (type) == QUAL_UNION_TYPE
&& CONTAINS_PLACEHOLDER_P (DECL_QUALIFIER (field)))
|| type_contains_placeholder_p (TREE_TYPE (field))))
{
ret = true;
break;
}
/* Now remove us from seen_types and return the result. */
if (seen_types == type)
seen_types = 0;
else
seen_types = TREE_CHAIN (seen_types);
return ret;
}
default:
abort ();
}
}
/* Return 1 if EXP contains any expressions that produce cleanups for an
outer scope to deal with. Used by fold. */
int
has_cleanups (tree exp)
{
int i, nops, cmp;
if (! TREE_SIDE_EFFECTS (exp))
return 0;
switch (TREE_CODE (exp))
{
case TARGET_EXPR:
case GOTO_SUBROUTINE_EXPR:
case WITH_CLEANUP_EXPR:
return 1;
case CLEANUP_POINT_EXPR:
return 0;
case CALL_EXPR:
for (exp = TREE_OPERAND (exp, 1); exp; exp = TREE_CHAIN (exp))
{
cmp = has_cleanups (TREE_VALUE (exp));
if (cmp)
return cmp;
}
return 0;
default:
break;
}
/* This general rule works for most tree codes. All exceptions should be
handled above. If this is a language-specific tree code, we can't
trust what might be in the operand, so say we don't know
the situation. */
if ((int) TREE_CODE (exp) >= (int) LAST_AND_UNUSED_TREE_CODE)
return -1;
nops = first_rtl_op (TREE_CODE (exp));
for (i = 0; i < nops; i++)
if (TREE_OPERAND (exp, i) != 0)
{
int type = TREE_CODE_CLASS (TREE_CODE (TREE_OPERAND (exp, i)));
if (type == 'e' || type == '<' || type == '1' || type == '2'
|| type == 'r' || type == 's')
{
cmp = has_cleanups (TREE_OPERAND (exp, i));
if (cmp)
return cmp;
}
}
return 0;
}
/* Given a tree EXP, a FIELD_DECL F, and a replacement value R,
return a tree with all occurrences of references to F in a
PLACEHOLDER_EXPR replaced by R. Note that we assume here that EXP
contains only arithmetic expressions or a CALL_EXPR with a
PLACEHOLDER_EXPR occurring only in its arglist. */
tree
substitute_in_expr (tree exp, tree f, tree r)
{
enum tree_code code = TREE_CODE (exp);
tree op0, op1, op2;
tree new;
tree inner;
switch (TREE_CODE_CLASS (code))
{
case 'c':
case 'd':
return exp;
case 'x':
if (code == PLACEHOLDER_EXPR)
return exp;
else if (code == TREE_LIST)
{
op0 = (TREE_CHAIN (exp) == 0
? 0 : substitute_in_expr (TREE_CHAIN (exp), f, r));
op1 = substitute_in_expr (TREE_VALUE (exp), f, r);
if (op0 == TREE_CHAIN (exp) && op1 == TREE_VALUE (exp))
return exp;
return tree_cons (TREE_PURPOSE (exp), op1, op0);
}
abort ();
case '1':
case '2':
case '<':
case 'e':
switch (TREE_CODE_LENGTH (code))
{
case 1:
op0 = substitute_in_expr (TREE_OPERAND (exp, 0), f, r);
if (op0 == TREE_OPERAND (exp, 0))
return exp;
if (code == NON_LVALUE_EXPR)
return op0;
new = fold (build1 (code, TREE_TYPE (exp), op0));
break;
case 2:
/* An RTL_EXPR cannot contain a PLACEHOLDER_EXPR; a CONSTRUCTOR
could, but we don't support it. */
if (code == RTL_EXPR)
return exp;
else if (code == CONSTRUCTOR)
abort ();
op0 = TREE_OPERAND (exp, 0);
op1 = TREE_OPERAND (exp, 1);
if (CONTAINS_PLACEHOLDER_P (op0))
op0 = substitute_in_expr (op0, f, r);
if (CONTAINS_PLACEHOLDER_P (op1))
op1 = substitute_in_expr (op1, f, r);
if (op0 == TREE_OPERAND (exp, 0) && op1 == TREE_OPERAND (exp, 1))
return exp;
new = fold (build (code, TREE_TYPE (exp), op0, op1));
break;
case 3:
/* It cannot be that anything inside a SAVE_EXPR contains a
PLACEHOLDER_EXPR. */
if (code == SAVE_EXPR)
return exp;
else if (code == CALL_EXPR)
{
op1 = substitute_in_expr (TREE_OPERAND (exp, 1), f, r);
if (op1 == TREE_OPERAND (exp, 1))
return exp;
return build (code, TREE_TYPE (exp),
TREE_OPERAND (exp, 0), op1, NULL_TREE);
}
else if (code != COND_EXPR)
abort ();
op0 = TREE_OPERAND (exp, 0);
op1 = TREE_OPERAND (exp, 1);
op2 = TREE_OPERAND (exp, 2);
if (CONTAINS_PLACEHOLDER_P (op0))
op0 = substitute_in_expr (op0, f, r);
if (CONTAINS_PLACEHOLDER_P (op1))
op1 = substitute_in_expr (op1, f, r);
if (CONTAINS_PLACEHOLDER_P (op2))
op2 = substitute_in_expr (op2, f, r);
if (op0 == TREE_OPERAND (exp, 0) && op1 == TREE_OPERAND (exp, 1)
&& op2 == TREE_OPERAND (exp, 2))
return exp;
new = fold (build (code, TREE_TYPE (exp), op0, op1, op2));
break;
default:
abort ();
}
break;
case 'r':
switch (code)
{
case COMPONENT_REF:
/* If this expression is getting a value from a PLACEHOLDER_EXPR
and it is the right field, replace it with R. */
for (inner = TREE_OPERAND (exp, 0);
TREE_CODE_CLASS (TREE_CODE (inner)) == 'r';
inner = TREE_OPERAND (inner, 0))
;
if (TREE_CODE (inner) == PLACEHOLDER_EXPR
&& TREE_OPERAND (exp, 1) == f)
return r;
/* If this expression hasn't been completed let, leave it
alone. */
if (TREE_CODE (inner) == PLACEHOLDER_EXPR
&& TREE_TYPE (inner) == 0)
return exp;
op0 = substitute_in_expr (TREE_OPERAND (exp, 0), f, r);
if (op0 == TREE_OPERAND (exp, 0))
return exp;
new = fold (build (code, TREE_TYPE (exp), op0,
TREE_OPERAND (exp, 1)));
break;
case BIT_FIELD_REF:
op0 = substitute_in_expr (TREE_OPERAND (exp, 0), f, r);
op1 = substitute_in_expr (TREE_OPERAND (exp, 1), f, r);
op2 = substitute_in_expr (TREE_OPERAND (exp, 2), f, r);
if (op0 == TREE_OPERAND (exp, 0) && op1 == TREE_OPERAND (exp, 1)
&& op2 == TREE_OPERAND (exp, 2))
return exp;
new = fold (build (code, TREE_TYPE (exp), op0, op1, op2));
break;
case INDIRECT_REF:
case BUFFER_REF:
op0 = substitute_in_expr (TREE_OPERAND (exp, 0), f, r);
if (op0 == TREE_OPERAND (exp, 0))
return exp;
new = fold (build1 (code, TREE_TYPE (exp), op0));
break;
default:
abort ();
}
break;
default:
abort ();
}
TREE_READONLY (new) = TREE_READONLY (exp);
return new;
}
/* Stabilize a reference so that we can use it any number of times
without causing its operands to be evaluated more than once.
Returns the stabilized reference. This works by means of save_expr,
so see the caveats in the comments about save_expr.
Also allows conversion expressions whose operands are references.
Any other kind of expression is returned unchanged. */
tree
stabilize_reference (tree ref)
{
tree result;
enum tree_code code = TREE_CODE (ref);
switch (code)
{
case VAR_DECL:
case PARM_DECL:
case RESULT_DECL:
/* No action is needed in this case. */
return ref;
case NOP_EXPR:
case CONVERT_EXPR:
case FLOAT_EXPR:
case FIX_TRUNC_EXPR:
case FIX_FLOOR_EXPR:
case FIX_ROUND_EXPR:
case FIX_CEIL_EXPR:
result = build_nt (code, stabilize_reference (TREE_OPERAND (ref, 0)));
break;
case INDIRECT_REF:
result = build_nt (INDIRECT_REF,
stabilize_reference_1 (TREE_OPERAND (ref, 0)));
break;
case COMPONENT_REF:
result = build_nt (COMPONENT_REF,
stabilize_reference (TREE_OPERAND (ref, 0)),
TREE_OPERAND (ref, 1));
break;
case BIT_FIELD_REF:
result = build_nt (BIT_FIELD_REF,
stabilize_reference (TREE_OPERAND (ref, 0)),
stabilize_reference_1 (TREE_OPERAND (ref, 1)),
stabilize_reference_1 (TREE_OPERAND (ref, 2)));
break;
case ARRAY_REF:
result = build_nt (ARRAY_REF,
stabilize_reference (TREE_OPERAND (ref, 0)),
stabilize_reference_1 (TREE_OPERAND (ref, 1)));
break;
case ARRAY_RANGE_REF:
result = build_nt (ARRAY_RANGE_REF,
stabilize_reference (TREE_OPERAND (ref, 0)),
stabilize_reference_1 (TREE_OPERAND (ref, 1)));
break;
case COMPOUND_EXPR:
/* We cannot wrap the first expression in a SAVE_EXPR, as then
it wouldn't be ignored. This matters when dealing with
volatiles. */
return stabilize_reference_1 (ref);
case RTL_EXPR:
result = build1 (INDIRECT_REF, TREE_TYPE (ref),
save_expr (build1 (ADDR_EXPR,
build_pointer_type (TREE_TYPE (ref)),
ref)));
break;
/* If arg isn't a kind of lvalue we recognize, make no change.
Caller should recognize the error for an invalid lvalue. */
default:
return ref;
case ERROR_MARK:
return error_mark_node;
}
TREE_TYPE (result) = TREE_TYPE (ref);
TREE_READONLY (result) = TREE_READONLY (ref);
TREE_SIDE_EFFECTS (result) = TREE_SIDE_EFFECTS (ref);
TREE_THIS_VOLATILE (result) = TREE_THIS_VOLATILE (ref);
return result;
}
/* Subroutine of stabilize_reference; this is called for subtrees of
references. Any expression with side-effects must be put in a SAVE_EXPR
to ensure that it is only evaluated once.
We don't put SAVE_EXPR nodes around everything, because assigning very
simple expressions to temporaries causes us to miss good opportunities
for optimizations. Among other things, the opportunity to fold in the
addition of a constant into an addressing mode often gets lost, e.g.
"y[i+1] += x;". In general, we take the approach that we should not make
an assignment unless we are forced into it - i.e., that any non-side effect
operator should be allowed, and that cse should take care of coalescing
multiple utterances of the same expression should that prove fruitful. */
tree
stabilize_reference_1 (tree e)
{
tree result;
enum tree_code code = TREE_CODE (e);
/* We cannot ignore const expressions because it might be a reference
to a const array but whose index contains side-effects. But we can
ignore things that are actual constant or that already have been
handled by this function. */
if (TREE_CONSTANT (e) || code == SAVE_EXPR)
return e;
switch (TREE_CODE_CLASS (code))
{
case 'x':
case 't':
case 'd':
case 'b':
case '<':
case 's':
case 'e':
case 'r':
/* If the expression has side-effects, then encase it in a SAVE_EXPR
so that it will only be evaluated once. */
/* The reference (r) and comparison (<) classes could be handled as
below, but it is generally faster to only evaluate them once. */
if (TREE_SIDE_EFFECTS (e))
return save_expr (e);
return e;
case 'c':
/* Constants need no processing. In fact, we should never reach
here. */
return e;
case '2':
/* Division is slow and tends to be compiled with jumps,
especially the division by powers of 2 that is often
found inside of an array reference. So do it just once. */
if (code == TRUNC_DIV_EXPR || code == TRUNC_MOD_EXPR
|| code == FLOOR_DIV_EXPR || code == FLOOR_MOD_EXPR
|| code == CEIL_DIV_EXPR || code == CEIL_MOD_EXPR
|| code == ROUND_DIV_EXPR || code == ROUND_MOD_EXPR)
return save_expr (e);
/* Recursively stabilize each operand. */
result = build_nt (code, stabilize_reference_1 (TREE_OPERAND (e, 0)),
stabilize_reference_1 (TREE_OPERAND (e, 1)));
break;
case '1':
/* Recursively stabilize each operand. */
result = build_nt (code, stabilize_reference_1 (TREE_OPERAND (e, 0)));
break;
default:
abort ();
}
TREE_TYPE (result) = TREE_TYPE (e);
TREE_READONLY (result) = TREE_READONLY (e);
TREE_SIDE_EFFECTS (result) = TREE_SIDE_EFFECTS (e);
TREE_THIS_VOLATILE (result) = TREE_THIS_VOLATILE (e);
return result;
}
/* Low-level constructors for expressions. */
/* Build an expression of code CODE, data type TYPE,
and operands as specified by the arguments ARG1 and following arguments.
Expressions and reference nodes can be created this way.
Constants, decls, types and misc nodes cannot be. */
tree
build (enum tree_code code, tree tt, ...)
{
tree t;
int length;
int i;
int fro;
int constant;
va_list p;
tree node;
va_start (p, tt);
t = make_node (code);
length = TREE_CODE_LENGTH (code);
TREE_TYPE (t) = tt;
/* Below, we automatically set TREE_SIDE_EFFECTS and TREE_READONLY for the
result based on those same flags for the arguments. But if the
arguments aren't really even `tree' expressions, we shouldn't be trying
to do this. */
fro = first_rtl_op (code);
/* Expressions without side effects may be constant if their
arguments are as well. */
constant = (TREE_CODE_CLASS (code) == '<'
|| TREE_CODE_CLASS (code) == '1'
|| TREE_CODE_CLASS (code) == '2'
|| TREE_CODE_CLASS (code) == 'c');
if (length == 2)
{
/* This is equivalent to the loop below, but faster. */
tree arg0 = va_arg (p, tree);
tree arg1 = va_arg (p, tree);
TREE_OPERAND (t, 0) = arg0;
TREE_OPERAND (t, 1) = arg1;
TREE_READONLY (t) = 1;
if (arg0 && fro > 0)
{
if (TREE_SIDE_EFFECTS (arg0))
TREE_SIDE_EFFECTS (t) = 1;
if (!TREE_READONLY (arg0))
TREE_READONLY (t) = 0;
if (!TREE_CONSTANT (arg0))
constant = 0;
}
if (arg1 && fro > 1)
{
if (TREE_SIDE_EFFECTS (arg1))
TREE_SIDE_EFFECTS (t) = 1;
if (!TREE_READONLY (arg1))
TREE_READONLY (t) = 0;
if (!TREE_CONSTANT (arg1))
constant = 0;
}
}
else if (length == 1)
{
tree arg0 = va_arg (p, tree);
/* The only one-operand cases we handle here are those with side-effects.
Others are handled with build1. So don't bother checked if the
arg has side-effects since we'll already have set it.
??? This really should use build1 too. */
if (TREE_CODE_CLASS (code) != 's')
abort ();
TREE_OPERAND (t, 0) = arg0;
}
else
{
for (i = 0; i < length; i++)
{
tree operand = va_arg (p, tree);
TREE_OPERAND (t, i) = operand;
if (operand && fro > i)
{
if (TREE_SIDE_EFFECTS (operand))
TREE_SIDE_EFFECTS (t) = 1;
if (!TREE_CONSTANT (operand))
constant = 0;
}
}
}
va_end (p);
TREE_CONSTANT (t) = constant;
if (code == CALL_EXPR && !TREE_SIDE_EFFECTS (t))
{
/* Calls have side-effects, except those to const or
pure functions. */
i = call_expr_flags (t);
if (!(i & (ECF_CONST | ECF_PURE)))
TREE_SIDE_EFFECTS (t) = 1;
/* And even those have side-effects if their arguments do. */
else for (node = TREE_OPERAND (t, 1); node; node = TREE_CHAIN (node))
if (TREE_SIDE_EFFECTS (TREE_VALUE (node)))
{
TREE_SIDE_EFFECTS (t) = 1;
break;
}
}
return t;
}
/* Same as above, but only builds for unary operators.
Saves lions share of calls to `build'; cuts down use
of varargs, which is expensive for RISC machines. */
tree
build1 (enum tree_code code, tree type, tree node)
{
int length = sizeof (struct tree_exp);
#ifdef GATHER_STATISTICS
tree_node_kind kind;
#endif
tree t;
#ifdef GATHER_STATISTICS
switch (TREE_CODE_CLASS (code))
{
case 's': /* an expression with side effects */
kind = s_kind;
break;
case 'r': /* a reference */
kind = r_kind;
break;
default:
kind = e_kind;
break;
}
tree_node_counts[(int) kind]++;
tree_node_sizes[(int) kind] += length;
#endif
#ifdef ENABLE_CHECKING
if (TREE_CODE_CLASS (code) == '2'
|| TREE_CODE_CLASS (code) == '<'
|| TREE_CODE_LENGTH (code) != 1)
abort ();
#endif /* ENABLE_CHECKING */
t = ggc_alloc_tree (length);
memset (t, 0, sizeof (struct tree_common));
TREE_SET_CODE (t, code);
TREE_TYPE (t) = type;
TREE_COMPLEXITY (t) = 0;
TREE_OPERAND (t, 0) = node;
if (node && first_rtl_op (code) != 0)
{
TREE_SIDE_EFFECTS (t) = TREE_SIDE_EFFECTS (node);
TREE_READONLY (t) = TREE_READONLY (node);
}
if (TREE_CODE_CLASS (code) == 's')
TREE_SIDE_EFFECTS (t) = 1;
else switch (code)
{
case INIT_EXPR:
case MODIFY_EXPR:
case VA_ARG_EXPR:
case RTL_EXPR:
case PREDECREMENT_EXPR:
case PREINCREMENT_EXPR:
case POSTDECREMENT_EXPR:
case POSTINCREMENT_EXPR:
/* All of these have side-effects, no matter what their
operands are. */
TREE_SIDE_EFFECTS (t) = 1;
TREE_READONLY (t) = 0;
break;
case INDIRECT_REF:
/* Whether a dereference is readonly has nothing to do with whether
its operand is readonly. */
TREE_READONLY (t) = 0;
break;
case ADDR_EXPR:
if (node)
{
/* The address of a volatile decl or reference does not have
side-effects. But be careful not to ignore side-effects from
other sources deeper in the expression--if node is a _REF and
one of its operands has side-effects, so do we. */
if (TREE_THIS_VOLATILE (node))
{
TREE_SIDE_EFFECTS (t) = 0;
if (!DECL_P (node))
{
int i = first_rtl_op (TREE_CODE (node)) - 1;
for (; i >= 0; --i)
{
if (TREE_SIDE_EFFECTS (TREE_OPERAND (node, i)))
TREE_SIDE_EFFECTS (t) = 1;
}
}
}
}
break;
default:
if (TREE_CODE_CLASS (code) == '1' && node && TREE_CONSTANT (node))
TREE_CONSTANT (t) = 1;
break;
}
return t;
}
/* Similar except don't specify the TREE_TYPE
and leave the TREE_SIDE_EFFECTS as 0.
It is permissible for arguments to be null,
or even garbage if their values do not matter. */
tree
build_nt (enum tree_code code, ...)
{
tree t;
int length;
int i;
va_list p;
va_start (p, code);
t = make_node (code);
length = TREE_CODE_LENGTH (code);
for (i = 0; i < length; i++)
TREE_OPERAND (t, i) = va_arg (p, tree);
va_end (p);
return t;
}
/* Create a DECL_... node of code CODE, name NAME and data type TYPE.
We do NOT enter this node in any sort of symbol table.
layout_decl is used to set up the decl's storage layout.
Other slots are initialized to 0 or null pointers. */
tree
build_decl (enum tree_code code, tree name, tree type)
{
tree t;
t = make_node (code);
/* if (type == error_mark_node)
type = integer_type_node; */
/* That is not done, deliberately, so that having error_mark_node
as the type can suppress useless errors in the use of this variable. */
DECL_NAME (t) = name;
TREE_TYPE (t) = type;
if (code == VAR_DECL || code == PARM_DECL || code == RESULT_DECL)
layout_decl (t, 0);
else if (code == FUNCTION_DECL)
DECL_MODE (t) = FUNCTION_MODE;
return t;
}
/* BLOCK nodes are used to represent the structure of binding contours
and declarations, once those contours have been exited and their contents
compiled. This information is used for outputting debugging info. */
tree
build_block (tree vars, tree tags ATTRIBUTE_UNUSED, tree subblocks,
tree supercontext, tree chain)
{
tree block = make_node (BLOCK);
BLOCK_VARS (block) = vars;
BLOCK_SUBBLOCKS (block) = subblocks;
BLOCK_SUPERCONTEXT (block) = supercontext;
BLOCK_CHAIN (block) = chain;
return block;
}
/* EXPR_WITH_FILE_LOCATION are used to keep track of the exact
location where an expression or an identifier were encountered. It
is necessary for languages where the frontend parser will handle
recursively more than one file (Java is one of them). */
tree
build_expr_wfl (tree node, const char *file, int line, int col)
{
static const char *last_file = 0;
static tree last_filenode = NULL_TREE;
tree wfl = make_node (EXPR_WITH_FILE_LOCATION);
EXPR_WFL_NODE (wfl) = node;
EXPR_WFL_SET_LINECOL (wfl, line, col);
if (file != last_file)
{
last_file = file;
last_filenode = file ? get_identifier (file) : NULL_TREE;
}
EXPR_WFL_FILENAME_NODE (wfl) = last_filenode;
if (node)
{
TREE_SIDE_EFFECTS (wfl) = TREE_SIDE_EFFECTS (node);
TREE_TYPE (wfl) = TREE_TYPE (node);
}
return wfl;
}
/* Return a declaration like DDECL except that its DECL_ATTRIBUTES
is ATTRIBUTE. */
tree
build_decl_attribute_variant (tree ddecl, tree attribute)
{
DECL_ATTRIBUTES (ddecl) = attribute;
return ddecl;
}
/* Return a type like TTYPE except that its TYPE_ATTRIBUTE
is ATTRIBUTE.
Record such modified types already made so we don't make duplicates. */
tree
build_type_attribute_variant (tree ttype, tree attribute)
{
if (! attribute_list_equal (TYPE_ATTRIBUTES (ttype), attribute))
{
unsigned int hashcode;
tree ntype;
ntype = copy_node (ttype);
TYPE_POINTER_TO (ntype) = 0;
TYPE_REFERENCE_TO (ntype) = 0;
TYPE_ATTRIBUTES (ntype) = attribute;
/* Create a new main variant of TYPE. */
TYPE_MAIN_VARIANT (ntype) = ntype;
TYPE_NEXT_VARIANT (ntype) = 0;
set_type_quals (ntype, TYPE_UNQUALIFIED);
hashcode = (TYPE_HASH (TREE_CODE (ntype))
+ TYPE_HASH (TREE_TYPE (ntype))
+ attribute_hash_list (attribute));
switch (TREE_CODE (ntype))
{
case FUNCTION_TYPE:
hashcode += TYPE_HASH (TYPE_ARG_TYPES (ntype));
break;
case ARRAY_TYPE:
hashcode += TYPE_HASH (TYPE_DOMAIN (ntype));
break;
case INTEGER_TYPE:
hashcode += TYPE_HASH (TYPE_MAX_VALUE (ntype));
break;
case REAL_TYPE:
hashcode += TYPE_HASH (TYPE_PRECISION (ntype));
break;
default:
break;
}
ntype = type_hash_canon (hashcode, ntype);
ttype = build_qualified_type (ntype, TYPE_QUALS (ttype));
}
return ttype;
}
/* Return nonzero if IDENT is a valid name for attribute ATTR,
or zero if not.
We try both `text' and `__text__', ATTR may be either one. */
/* ??? It might be a reasonable simplification to require ATTR to be only
`text'. One might then also require attribute lists to be stored in
their canonicalized form. */
int
is_attribute_p (const char *attr, tree ident)
{
int ident_len, attr_len;
const char *p;
if (TREE_CODE (ident) != IDENTIFIER_NODE)
return 0;
if (strcmp (attr, IDENTIFIER_POINTER (ident)) == 0)
return 1;
p = IDENTIFIER_POINTER (ident);
ident_len = strlen (p);
attr_len = strlen (attr);
/* If ATTR is `__text__', IDENT must be `text'; and vice versa. */
if (attr[0] == '_')
{
if (attr[1] != '_'
|| attr[attr_len - 2] != '_'
|| attr[attr_len - 1] != '_')
abort ();
if (ident_len == attr_len - 4
&& strncmp (attr + 2, p, attr_len - 4) == 0)
return 1;
}
else
{
if (ident_len == attr_len + 4
&& p[0] == '_' && p[1] == '_'
&& p[ident_len - 2] == '_' && p[ident_len - 1] == '_'
&& strncmp (attr, p + 2, attr_len) == 0)
return 1;
}
return 0;
}
/* Given an attribute name and a list of attributes, return a pointer to the
attribute's list element if the attribute is part of the list, or NULL_TREE
if not found. If the attribute appears more than once, this only
returns the first occurrence; the TREE_CHAIN of the return value should
be passed back in if further occurrences are wanted. */
tree
lookup_attribute (const char *attr_name, tree list)
{
tree l;
for (l = list; l; l = TREE_CHAIN (l))
{
if (TREE_CODE (TREE_PURPOSE (l)) != IDENTIFIER_NODE)
abort ();
if (is_attribute_p (attr_name, TREE_PURPOSE (l)))
return l;
}
return NULL_TREE;
}
/* Return an attribute list that is the union of a1 and a2. */
tree
merge_attributes (tree a1, tree a2)
{
tree attributes;
/* Either one unset? Take the set one. */
if ((attributes = a1) == 0)
attributes = a2;
/* One that completely contains the other? Take it. */
else if (a2 != 0 && ! attribute_list_contained (a1, a2))
{
if (attribute_list_contained (a2, a1))
attributes = a2;
else
{
/* Pick the longest list, and hang on the other list. */
if (list_length (a1) < list_length (a2))
attributes = a2, a2 = a1;
for (; a2 != 0; a2 = TREE_CHAIN (a2))
{
tree a;
for (a = lookup_attribute (IDENTIFIER_POINTER (TREE_PURPOSE (a2)),
attributes);
a != NULL_TREE;
a = lookup_attribute (IDENTIFIER_POINTER (TREE_PURPOSE (a2)),
TREE_CHAIN (a)))
{
if (simple_cst_equal (TREE_VALUE (a), TREE_VALUE (a2)) == 1)
break;
}
if (a == NULL_TREE)
{
a1 = copy_node (a2);
TREE_CHAIN (a1) = attributes;
attributes = a1;
}
}
}
}
return attributes;
}
/* Given types T1 and T2, merge their attributes and return
the result. */
tree
merge_type_attributes (tree t1, tree t2)
{
return merge_attributes (TYPE_ATTRIBUTES (t1),
TYPE_ATTRIBUTES (t2));
}
/* Given decls OLDDECL and NEWDECL, merge their attributes and return
the result. */
tree
merge_decl_attributes (tree olddecl, tree newdecl)
{
return merge_attributes (DECL_ATTRIBUTES (olddecl),
DECL_ATTRIBUTES (newdecl));
}
#ifdef TARGET_DLLIMPORT_DECL_ATTRIBUTES
/* Specialization of merge_decl_attributes for various Windows targets.
This handles the following situation:
__declspec (dllimport) int foo;
int foo;
The second instance of `foo' nullifies the dllimport. */
tree
merge_dllimport_decl_attributes (tree old, tree new)
{
tree a;
int delete_dllimport_p;
old = DECL_ATTRIBUTES (old);
new = DECL_ATTRIBUTES (new);
/* What we need to do here is remove from `old' dllimport if it doesn't
appear in `new'. dllimport behaves like extern: if a declaration is
marked dllimport and a definition appears later, then the object
is not dllimport'd. */
if (lookup_attribute ("dllimport", old) != NULL_TREE
&& lookup_attribute ("dllimport", new) == NULL_TREE)
delete_dllimport_p = 1;
else
delete_dllimport_p = 0;
a = merge_attributes (old, new);
if (delete_dllimport_p)
{
tree prev, t;
/* Scan the list for dllimport and delete it. */
for (prev = NULL_TREE, t = a; t; prev = t, t = TREE_CHAIN (t))
{
if (is_attribute_p ("dllimport", TREE_PURPOSE (t)))
{
if (prev == NULL_TREE)
a = TREE_CHAIN (a);
else
TREE_CHAIN (prev) = TREE_CHAIN (t);
break;
}
}
}
return a;
}
#endif /* TARGET_DLLIMPORT_DECL_ATTRIBUTES */
/* Set the type qualifiers for TYPE to TYPE_QUALS, which is a bitmask
of the various TYPE_QUAL values. */
static void
set_type_quals (tree type, int type_quals)
{
TYPE_READONLY (type) = (type_quals & TYPE_QUAL_CONST) != 0;
TYPE_VOLATILE (type) = (type_quals & TYPE_QUAL_VOLATILE) != 0;
TYPE_RESTRICT (type) = (type_quals & TYPE_QUAL_RESTRICT) != 0;
}
/* Return a version of the TYPE, qualified as indicated by the
TYPE_QUALS, if one exists. If no qualified version exists yet,
return NULL_TREE. */
tree
get_qualified_type (tree type, int type_quals)
{
tree t;
/* Search the chain of variants to see if there is already one there just
like the one we need to have. If so, use that existing one. We must
preserve the TYPE_NAME, since there is code that depends on this. */
for (t = TYPE_MAIN_VARIANT (type); t; t = TYPE_NEXT_VARIANT (t))
if (TYPE_QUALS (t) == type_quals && TYPE_NAME (t) == TYPE_NAME (type)
&& TYPE_CONTEXT (t) == TYPE_CONTEXT (type)
&& attribute_list_equal (TYPE_ATTRIBUTES (t), TYPE_ATTRIBUTES (type)))
return t;
return NULL_TREE;
}
/* Like get_qualified_type, but creates the type if it does not
exist. This function never returns NULL_TREE. */
tree
build_qualified_type (tree type, int type_quals)
{
tree t;
/* See if we already have the appropriate qualified variant. */
t = get_qualified_type (type, type_quals);
/* If not, build it. */
if (!t)
{
t = build_type_copy (type);
set_type_quals (t, type_quals);
}
return t;
}
/* Create a new variant of TYPE, equivalent but distinct.
This is so the caller can modify it. */
tree
build_type_copy (tree type)
{
tree t, m = TYPE_MAIN_VARIANT (type);
t = copy_node (type);
TYPE_POINTER_TO (t) = 0;
TYPE_REFERENCE_TO (t) = 0;
/* Add this type to the chain of variants of TYPE. */
TYPE_NEXT_VARIANT (t) = TYPE_NEXT_VARIANT (m);
TYPE_NEXT_VARIANT (m) = t;
return t;
}
/* Hashing of types so that we don't make duplicates.
The entry point is `type_hash_canon'. */
/* Compute a hash code for a list of types (chain of TREE_LIST nodes
with types in the TREE_VALUE slots), by adding the hash codes
of the individual types. */
unsigned int
type_hash_list (tree list)
{
unsigned int hashcode;
tree tail;
for (hashcode = 0, tail = list; tail; tail = TREE_CHAIN (tail))
hashcode += TYPE_HASH (TREE_VALUE (tail));
return hashcode;
}
/* These are the Hashtable callback functions. */
/* Returns true if the types are equal. */
static int
type_hash_eq (const void *va, const void *vb)
{
const struct type_hash *a = va, *b = vb;
if (a->hash == b->hash
&& TREE_CODE (a->type) == TREE_CODE (b->type)
&& TREE_TYPE (a->type) == TREE_TYPE (b->type)
&& attribute_list_equal (TYPE_ATTRIBUTES (a->type),
TYPE_ATTRIBUTES (b->type))
&& TYPE_ALIGN (a->type) == TYPE_ALIGN (b->type)
&& (TYPE_MAX_VALUE (a->type) == TYPE_MAX_VALUE (b->type)
|| tree_int_cst_equal (TYPE_MAX_VALUE (a->type),
TYPE_MAX_VALUE (b->type)))
&& (TYPE_MIN_VALUE (a->type) == TYPE_MIN_VALUE (b->type)
|| tree_int_cst_equal (TYPE_MIN_VALUE (a->type),
TYPE_MIN_VALUE (b->type)))
/* Note that TYPE_DOMAIN is TYPE_ARG_TYPES for FUNCTION_TYPE. */
&& (TYPE_DOMAIN (a->type) == TYPE_DOMAIN (b->type)
|| (TYPE_DOMAIN (a->type)
&& TREE_CODE (TYPE_DOMAIN (a->type)) == TREE_LIST
&& TYPE_DOMAIN (b->type)
&& TREE_CODE (TYPE_DOMAIN (b->type)) == TREE_LIST
&& type_list_equal (TYPE_DOMAIN (a->type),
TYPE_DOMAIN (b->type)))))
return 1;
return 0;
}
/* Return the cached hash value. */
static hashval_t
type_hash_hash (const void *item)
{
return ((const struct type_hash *) item)->hash;
}
/* Look in the type hash table for a type isomorphic to TYPE.
If one is found, return it. Otherwise return 0. */
tree
type_hash_lookup (unsigned int hashcode, tree type)
{
struct type_hash *h, in;
/* The TYPE_ALIGN field of a type is set by layout_type(), so we
must call that routine before comparing TYPE_ALIGNs. */
layout_type (type);
in.hash = hashcode;
in.type = type;
h = htab_find_with_hash (type_hash_table, &in, hashcode);
if (h)
return h->type;
return NULL_TREE;
}
/* Add an entry to the type-hash-table
for a type TYPE whose hash code is HASHCODE. */
void
type_hash_add (unsigned int hashcode, tree type)
{
struct type_hash *h;
void **loc;
h = ggc_alloc (sizeof (struct type_hash));
h->hash = hashcode;
h->type = type;
loc = htab_find_slot_with_hash (type_hash_table, h, hashcode, INSERT);
*(struct type_hash **) loc = h;
}
/* Given TYPE, and HASHCODE its hash code, return the canonical
object for an identical type if one already exists.
Otherwise, return TYPE, and record it as the canonical object
if it is a permanent object.
To use this function, first create a type of the sort you want.
Then compute its hash code from the fields of the type that
make it different from other similar types.
Then call this function and use the value.
This function frees the type you pass in if it is a duplicate. */
/* Set to 1 to debug without canonicalization. Never set by program. */
int debug_no_type_hash = 0;
tree
type_hash_canon (unsigned int hashcode, tree type)
{
tree t1;
if (debug_no_type_hash)
return type;
/* See if the type is in the hash table already. If so, return it.
Otherwise, add the type. */
t1 = type_hash_lookup (hashcode, type);
if (t1 != 0)
{
#ifdef GATHER_STATISTICS
tree_node_counts[(int) t_kind]--;
tree_node_sizes[(int) t_kind] -= sizeof (struct tree_type);
#endif
return t1;
}
else
{
type_hash_add (hashcode, type);
return type;
}
}
/* See if the data pointed to by the type hash table is marked. We consider
it marked if the type is marked or if a debug type number or symbol
table entry has been made for the type. This reduces the amount of
debugging output and eliminates that dependency of the debug output on
the number of garbage collections. */
static int
type_hash_marked_p (const void *p)
{
tree type = ((struct type_hash *) p)->type;
return ggc_marked_p (type) || TYPE_SYMTAB_POINTER (type);
}
static void
print_type_hash_statistics (void)
{
fprintf (stderr, "Type hash: size %ld, %ld elements, %f collisions\n",
(long) htab_size (type_hash_table),
(long) htab_elements (type_hash_table),
htab_collisions (type_hash_table));
}
/* Compute a hash code for a list of attributes (chain of TREE_LIST nodes
with names in the TREE_PURPOSE slots and args in the TREE_VALUE slots),
by adding the hash codes of the individual attributes. */
unsigned int
attribute_hash_list (tree list)
{
unsigned int hashcode;
tree tail;
for (hashcode = 0, tail = list; tail; tail = TREE_CHAIN (tail))
/* ??? Do we want to add in TREE_VALUE too? */
hashcode += TYPE_HASH (TREE_PURPOSE (tail));
return hashcode;
}
/* Given two lists of attributes, return true if list l2 is
equivalent to l1. */
int
attribute_list_equal (tree l1, tree l2)
{
return attribute_list_contained (l1, l2)
&& attribute_list_contained (l2, l1);
}
/* Given two lists of attributes, return true if list L2 is
completely contained within L1. */
/* ??? This would be faster if attribute names were stored in a canonicalized
form. Otherwise, if L1 uses `foo' and L2 uses `__foo__', the long method
must be used to show these elements are equivalent (which they are). */
/* ??? It's not clear that attributes with arguments will always be handled
correctly. */
int
attribute_list_contained (tree l1, tree l2)
{
tree t1, t2;
/* First check the obvious, maybe the lists are identical. */
if (l1 == l2)
return 1;
/* Maybe the lists are similar. */
for (t1 = l1, t2 = l2;
t1 != 0 && t2 != 0
&& TREE_PURPOSE (t1) == TREE_PURPOSE (t2)
&& TREE_VALUE (t1) == TREE_VALUE (t2);
t1 = TREE_CHAIN (t1), t2 = TREE_CHAIN (t2));
/* Maybe the lists are equal. */
if (t1 == 0 && t2 == 0)
return 1;
for (; t2 != 0; t2 = TREE_CHAIN (t2))
{
tree attr;
for (attr = lookup_attribute (IDENTIFIER_POINTER (TREE_PURPOSE (t2)), l1);
attr != NULL_TREE;
attr = lookup_attribute (IDENTIFIER_POINTER (TREE_PURPOSE (t2)),
TREE_CHAIN (attr)))
{
if (simple_cst_equal (TREE_VALUE (t2), TREE_VALUE (attr)) == 1)
break;
}
if (attr == 0)
return 0;
if (simple_cst_equal (TREE_VALUE (t2), TREE_VALUE (attr)) != 1)
return 0;
}
return 1;
}
/* Given two lists of types
(chains of TREE_LIST nodes with types in the TREE_VALUE slots)
return 1 if the lists contain the same types in the same order.
Also, the TREE_PURPOSEs must match. */
int
type_list_equal (tree l1, tree l2)
{
tree t1, t2;
for (t1 = l1, t2 = l2; t1 && t2; t1 = TREE_CHAIN (t1), t2 = TREE_CHAIN (t2))
if (TREE_VALUE (t1) != TREE_VALUE (t2)
|| (TREE_PURPOSE (t1) != TREE_PURPOSE (t2)
&& ! (1 == simple_cst_equal (TREE_PURPOSE (t1), TREE_PURPOSE (t2))
&& (TREE_TYPE (TREE_PURPOSE (t1))
== TREE_TYPE (TREE_PURPOSE (t2))))))
return 0;
return t1 == t2;
}
/* Returns the number of arguments to the FUNCTION_TYPE or METHOD_TYPE
given by TYPE. If the argument list accepts variable arguments,
then this function counts only the ordinary arguments. */
int
type_num_arguments (tree type)
{
int i = 0;
tree t;
for (t = TYPE_ARG_TYPES (type); t; t = TREE_CHAIN (t))
/* If the function does not take a variable number of arguments,
the last element in the list will have type `void'. */
if (VOID_TYPE_P (TREE_VALUE (t)))
break;
else
++i;
return i;
}
/* Nonzero if integer constants T1 and T2
represent the same constant value. */
int
tree_int_cst_equal (tree t1, tree t2)
{
if (t1 == t2)
return 1;
if (t1 == 0 || t2 == 0)
return 0;
if (TREE_CODE (t1) == INTEGER_CST
&& TREE_CODE (t2) == INTEGER_CST
&& TREE_INT_CST_LOW (t1) == TREE_INT_CST_LOW (t2)
&& TREE_INT_CST_HIGH (t1) == TREE_INT_CST_HIGH (t2))
return 1;
return 0;
}
/* Nonzero if integer constants T1 and T2 represent values that satisfy <.
The precise way of comparison depends on their data type. */
int
tree_int_cst_lt (tree t1, tree t2)
{
if (t1 == t2)
return 0;
if (TREE_UNSIGNED (TREE_TYPE (t1)) != TREE_UNSIGNED (TREE_TYPE (t2)))
{
int t1_sgn = tree_int_cst_sgn (t1);
int t2_sgn = tree_int_cst_sgn (t2);
if (t1_sgn < t2_sgn)
return 1;
else if (t1_sgn > t2_sgn)
return 0;
/* Otherwise, both are non-negative, so we compare them as
unsigned just in case one of them would overflow a signed
type. */
}
else if (! TREE_UNSIGNED (TREE_TYPE (t1)))
return INT_CST_LT (t1, t2);
return INT_CST_LT_UNSIGNED (t1, t2);
}
/* Returns -1 if T1 < T2, 0 if T1 == T2, and 1 if T1 > T2. */
int
tree_int_cst_compare (tree t1, tree t2)
{
if (tree_int_cst_lt (t1, t2))
return -1;
else if (tree_int_cst_lt (t2, t1))
return 1;
else
return 0;
}
/* Return 1 if T is an INTEGER_CST that can be manipulated efficiently on
the host. If POS is zero, the value can be represented in a single
HOST_WIDE_INT. If POS is nonzero, the value must be positive and can
be represented in a single unsigned HOST_WIDE_INT. */
int
host_integerp (tree t, int pos)
{
return (TREE_CODE (t) == INTEGER_CST
&& ! TREE_OVERFLOW (t)
&& ((TREE_INT_CST_HIGH (t) == 0
&&