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/* Tree lowering pass. This pass converts the GENERIC functions-as-trees
tree representation into the GIMPLE form.
Copyright (C) 2002-2013 Free Software Foundation, Inc.
Major work done by Sebastian Pop <s.pop@laposte.net>,
Diego Novillo <dnovillo@redhat.com> and Jason Merrill <jason@redhat.com>.
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 3, 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 COPYING3. If not see
<http://www.gnu.org/licenses/>. */
#include "config.h"
#include "system.h"
#include "coretypes.h"
#include "tm.h"
#include "tree.h"
#include "gimple.h"
#include "tree-iterator.h"
#include "tree-inline.h"
#include "tree-pretty-print.h"
#include "langhooks.h"
#include "tree-flow.h"
#include "cgraph.h"
#include "timevar.h"
#include "hashtab.h"
#include "flags.h"
#include "function.h"
#include "ggc.h"
#include "diagnostic-core.h"
#include "target.h"
#include "pointer-set.h"
#include "splay-tree.h"
#include "vec.h"
#include "gimple.h"
#include "langhooks-def.h" /* FIXME: for lhd_set_decl_assembler_name */
#include "tree-pass.h" /* FIXME: only for PROP_gimple_any */
enum gimplify_omp_var_data
{
GOVD_SEEN = 1,
GOVD_EXPLICIT = 2,
GOVD_SHARED = 4,
GOVD_PRIVATE = 8,
GOVD_FIRSTPRIVATE = 16,
GOVD_LASTPRIVATE = 32,
GOVD_REDUCTION = 64,
GOVD_LOCAL = 128,
GOVD_DEBUG_PRIVATE = 256,
GOVD_PRIVATE_OUTER_REF = 512,
GOVD_DATA_SHARE_CLASS = (GOVD_SHARED | GOVD_PRIVATE | GOVD_FIRSTPRIVATE
| GOVD_LASTPRIVATE | GOVD_REDUCTION | GOVD_LOCAL)
};
enum omp_region_type
{
ORT_WORKSHARE = 0,
ORT_PARALLEL = 2,
ORT_COMBINED_PARALLEL = 3,
ORT_TASK = 4,
ORT_UNTIED_TASK = 5
};
struct gimplify_omp_ctx
{
struct gimplify_omp_ctx *outer_context;
splay_tree variables;
struct pointer_set_t *privatized_types;
location_t location;
enum omp_clause_default_kind default_kind;
enum omp_region_type region_type;
};
static struct gimplify_ctx *gimplify_ctxp;
static struct gimplify_omp_ctx *gimplify_omp_ctxp;
/* Formal (expression) temporary table handling: multiple occurrences of
the same scalar expression are evaluated into the same temporary. */
typedef struct gimple_temp_hash_elt
{
tree val; /* Key */
tree temp; /* Value */
} elt_t;
/* Forward declaration. */
static enum gimplify_status gimplify_compound_expr (tree *, gimple_seq *, bool);
/* Mark X addressable. Unlike the langhook we expect X to be in gimple
form and we don't do any syntax checking. */
void
mark_addressable (tree x)
{
while (handled_component_p (x))
x = TREE_OPERAND (x, 0);
if (TREE_CODE (x) == MEM_REF
&& TREE_CODE (TREE_OPERAND (x, 0)) == ADDR_EXPR)
x = TREE_OPERAND (TREE_OPERAND (x, 0), 0);
if (TREE_CODE (x) != VAR_DECL
&& TREE_CODE (x) != PARM_DECL
&& TREE_CODE (x) != RESULT_DECL)
return;
TREE_ADDRESSABLE (x) = 1;
/* Also mark the artificial SSA_NAME that points to the partition of X. */
if (TREE_CODE (x) == VAR_DECL
&& !DECL_EXTERNAL (x)
&& !TREE_STATIC (x)
&& cfun->gimple_df != NULL
&& cfun->gimple_df->decls_to_pointers != NULL)
{
void *namep
= pointer_map_contains (cfun->gimple_df->decls_to_pointers, x);
if (namep)
TREE_ADDRESSABLE (*(tree *)namep) = 1;
}
}
/* Return a hash value for a formal temporary table entry. */
static hashval_t
gimple_tree_hash (const void *p)
{
tree t = ((const elt_t *) p)->val;
return iterative_hash_expr (t, 0);
}
/* Compare two formal temporary table entries. */
static int
gimple_tree_eq (const void *p1, const void *p2)
{
tree t1 = ((const elt_t *) p1)->val;
tree t2 = ((const elt_t *) p2)->val;
enum tree_code code = TREE_CODE (t1);
if (TREE_CODE (t2) != code
|| TREE_TYPE (t1) != TREE_TYPE (t2))
return 0;
if (!operand_equal_p (t1, t2, 0))
return 0;
#ifdef ENABLE_CHECKING
/* Only allow them to compare equal if they also hash equal; otherwise
results are nondeterminate, and we fail bootstrap comparison. */
gcc_assert (gimple_tree_hash (p1) == gimple_tree_hash (p2));
#endif
return 1;
}
/* Link gimple statement GS to the end of the sequence *SEQ_P. If
*SEQ_P is NULL, a new sequence is allocated. This function is
similar to gimple_seq_add_stmt, but does not scan the operands.
During gimplification, we need to manipulate statement sequences
before the def/use vectors have been constructed. */
void
gimple_seq_add_stmt_without_update (gimple_seq *seq_p, gimple gs)
{
gimple_stmt_iterator si;
if (gs == NULL)
return;
si = gsi_last (*seq_p);
gsi_insert_after_without_update (&si, gs, GSI_NEW_STMT);
}
/* Shorter alias name for the above function for use in gimplify.c
only. */
static inline void
gimplify_seq_add_stmt (gimple_seq *seq_p, gimple gs)
{
gimple_seq_add_stmt_without_update (seq_p, gs);
}
/* Append sequence SRC to the end of sequence *DST_P. If *DST_P is
NULL, a new sequence is allocated. This function is
similar to gimple_seq_add_seq, but does not scan the operands.
During gimplification, we need to manipulate statement sequences
before the def/use vectors have been constructed. */
static void
gimplify_seq_add_seq (gimple_seq *dst_p, gimple_seq src)
{
gimple_stmt_iterator si;
if (src == NULL)
return;
si = gsi_last (*dst_p);
gsi_insert_seq_after_without_update (&si, src, GSI_NEW_STMT);
}
/* Set up a context for the gimplifier. */
void
push_gimplify_context (struct gimplify_ctx *c)
{
memset (c, '\0', sizeof (*c));
c->prev_context = gimplify_ctxp;
gimplify_ctxp = c;
}
/* Tear down a context for the gimplifier. If BODY is non-null, then
put the temporaries into the outer BIND_EXPR. Otherwise, put them
in the local_decls.
BODY is not a sequence, but the first tuple in a sequence. */
void
pop_gimplify_context (gimple body)
{
struct gimplify_ctx *c = gimplify_ctxp;
gcc_assert (c
&& (!c->bind_expr_stack.exists ()
|| c->bind_expr_stack.is_empty ()));
c->bind_expr_stack.release ();
gimplify_ctxp = c->prev_context;
if (body)
declare_vars (c->temps, body, false);
else
record_vars (c->temps);
if (c->temp_htab)
htab_delete (c->temp_htab);
}
/* Push a GIMPLE_BIND tuple onto the stack of bindings. */
static void
gimple_push_bind_expr (gimple gimple_bind)
{
gimplify_ctxp->bind_expr_stack.reserve (8);
gimplify_ctxp->bind_expr_stack.safe_push (gimple_bind);
}
/* Pop the first element off the stack of bindings. */
static void
gimple_pop_bind_expr (void)
{
gimplify_ctxp->bind_expr_stack.pop ();
}
/* Return the first element of the stack of bindings. */
gimple
gimple_current_bind_expr (void)
{
return gimplify_ctxp->bind_expr_stack.last ();
}
/* Return the stack of bindings created during gimplification. */
vec<gimple>
gimple_bind_expr_stack (void)
{
return gimplify_ctxp->bind_expr_stack;
}
/* Return true iff there is a COND_EXPR between us and the innermost
CLEANUP_POINT_EXPR. This info is used by gimple_push_cleanup. */
static bool
gimple_conditional_context (void)
{
return gimplify_ctxp->conditions > 0;
}
/* Note that we've entered a COND_EXPR. */
static void
gimple_push_condition (void)
{
#ifdef ENABLE_GIMPLE_CHECKING
if (gimplify_ctxp->conditions == 0)
gcc_assert (gimple_seq_empty_p (gimplify_ctxp->conditional_cleanups));
#endif
++(gimplify_ctxp->conditions);
}
/* Note that we've left a COND_EXPR. If we're back at unconditional scope
now, add any conditional cleanups we've seen to the prequeue. */
static void
gimple_pop_condition (gimple_seq *pre_p)
{
int conds = --(gimplify_ctxp->conditions);
gcc_assert (conds >= 0);
if (conds == 0)
{
gimplify_seq_add_seq (pre_p, gimplify_ctxp->conditional_cleanups);
gimplify_ctxp->conditional_cleanups = NULL;
}
}
/* A stable comparison routine for use with splay trees and DECLs. */
static int
splay_tree_compare_decl_uid (splay_tree_key xa, splay_tree_key xb)
{
tree a = (tree) xa;
tree b = (tree) xb;
return DECL_UID (a) - DECL_UID (b);
}
/* Create a new omp construct that deals with variable remapping. */
static struct gimplify_omp_ctx *
new_omp_context (enum omp_region_type region_type)
{
struct gimplify_omp_ctx *c;
c = XCNEW (struct gimplify_omp_ctx);
c->outer_context = gimplify_omp_ctxp;
c->variables = splay_tree_new (splay_tree_compare_decl_uid, 0, 0);
c->privatized_types = pointer_set_create ();
c->location = input_location;
c->region_type = region_type;
if ((region_type & ORT_TASK) == 0)
c->default_kind = OMP_CLAUSE_DEFAULT_SHARED;
else
c->default_kind = OMP_CLAUSE_DEFAULT_UNSPECIFIED;
return c;
}
/* Destroy an omp construct that deals with variable remapping. */
static void
delete_omp_context (struct gimplify_omp_ctx *c)
{
splay_tree_delete (c->variables);
pointer_set_destroy (c->privatized_types);
XDELETE (c);
}
static void omp_add_variable (struct gimplify_omp_ctx *, tree, unsigned int);
static bool omp_notice_variable (struct gimplify_omp_ctx *, tree, bool);
/* Both gimplify the statement T and append it to *SEQ_P. This function
behaves exactly as gimplify_stmt, but you don't have to pass T as a
reference. */
void
gimplify_and_add (tree t, gimple_seq *seq_p)
{
gimplify_stmt (&t, seq_p);
}
/* Gimplify statement T into sequence *SEQ_P, and return the first
tuple in the sequence of generated tuples for this statement.
Return NULL if gimplifying T produced no tuples. */
static gimple
gimplify_and_return_first (tree t, gimple_seq *seq_p)
{
gimple_stmt_iterator last = gsi_last (*seq_p);
gimplify_and_add (t, seq_p);
if (!gsi_end_p (last))
{
gsi_next (&last);
return gsi_stmt (last);
}
else
return gimple_seq_first_stmt (*seq_p);
}
/* Strip off a legitimate source ending from the input string NAME of
length LEN. Rather than having to know the names used by all of
our front ends, we strip off an ending of a period followed by
up to five characters. (Java uses ".class".) */
static inline void
remove_suffix (char *name, int len)
{
int i;
for (i = 2; i < 8 && len > i; i++)
{
if (name[len - i] == '.')
{
name[len - i] = '\0';
break;
}
}
}
/* Create a new temporary name with PREFIX. Return an identifier. */
static GTY(()) unsigned int tmp_var_id_num;
tree
create_tmp_var_name (const char *prefix)
{
char *tmp_name;
if (prefix)
{
char *preftmp = ASTRDUP (prefix);
remove_suffix (preftmp, strlen (preftmp));
clean_symbol_name (preftmp);
prefix = preftmp;
}
ASM_FORMAT_PRIVATE_NAME (tmp_name, prefix ? prefix : "T", tmp_var_id_num++);
return get_identifier (tmp_name);
}
/* Create a new temporary variable declaration of type TYPE.
Do NOT push it into the current binding. */
tree
create_tmp_var_raw (tree type, const char *prefix)
{
tree tmp_var;
tmp_var = build_decl (input_location,
VAR_DECL, prefix ? create_tmp_var_name (prefix) : NULL,
type);
/* The variable was declared by the compiler. */
DECL_ARTIFICIAL (tmp_var) = 1;
/* And we don't want debug info for it. */
DECL_IGNORED_P (tmp_var) = 1;
/* Make the variable writable. */
TREE_READONLY (tmp_var) = 0;
DECL_EXTERNAL (tmp_var) = 0;
TREE_STATIC (tmp_var) = 0;
TREE_USED (tmp_var) = 1;
return tmp_var;
}
/* Create a new temporary variable declaration of type TYPE. DO push the
variable into the current binding. Further, assume that this is called
only from gimplification or optimization, at which point the creation of
certain types are bugs. */
tree
create_tmp_var (tree type, const char *prefix)
{
tree tmp_var;
/* We don't allow types that are addressable (meaning we can't make copies),
or incomplete. We also used to reject every variable size objects here,
but now support those for which a constant upper bound can be obtained.
The processing for variable sizes is performed in gimple_add_tmp_var,
point at which it really matters and possibly reached via paths not going
through this function, e.g. after direct calls to create_tmp_var_raw. */
gcc_assert (!TREE_ADDRESSABLE (type) && COMPLETE_TYPE_P (type));
tmp_var = create_tmp_var_raw (type, prefix);
gimple_add_tmp_var (tmp_var);
return tmp_var;
}
/* Create a new temporary variable declaration of type TYPE by calling
create_tmp_var and if TYPE is a vector or a complex number, mark the new
temporary as gimple register. */
tree
create_tmp_reg (tree type, const char *prefix)
{
tree tmp;
tmp = create_tmp_var (type, prefix);
if (TREE_CODE (type) == COMPLEX_TYPE
|| TREE_CODE (type) == VECTOR_TYPE)
DECL_GIMPLE_REG_P (tmp) = 1;
return tmp;
}
/* Returns true iff T is a valid RHS for an assignment to a renamed
user -- or front-end generated artificial -- variable. */
static bool
is_gimple_reg_rhs (tree t)
{
return get_gimple_rhs_class (TREE_CODE (t)) != GIMPLE_INVALID_RHS;
}
/* Returns true iff T is a valid RHS for an assignment to an un-renamed
LHS, or for a call argument. */
static bool
is_gimple_mem_rhs (tree t)
{
/* If we're dealing with a renamable type, either source or dest must be
a renamed variable. */
if (is_gimple_reg_type (TREE_TYPE (t)))
return is_gimple_val (t);
else
return is_gimple_val (t) || is_gimple_lvalue (t);
}
/* Return true if T is a CALL_EXPR or an expression that can be
assigned to a temporary. Note that this predicate should only be
used during gimplification. See the rationale for this in
gimplify_modify_expr. */
static bool
is_gimple_reg_rhs_or_call (tree t)
{
return (get_gimple_rhs_class (TREE_CODE (t)) != GIMPLE_INVALID_RHS
|| TREE_CODE (t) == CALL_EXPR);
}
/* Return true if T is a valid memory RHS or a CALL_EXPR. Note that
this predicate should only be used during gimplification. See the
rationale for this in gimplify_modify_expr. */
static bool
is_gimple_mem_rhs_or_call (tree t)
{
/* If we're dealing with a renamable type, either source or dest must be
a renamed variable. */
if (is_gimple_reg_type (TREE_TYPE (t)))
return is_gimple_val (t);
else
return (is_gimple_val (t) || is_gimple_lvalue (t)
|| TREE_CODE (t) == CALL_EXPR);
}
/* Create a temporary with a name derived from VAL. Subroutine of
lookup_tmp_var; nobody else should call this function. */
static inline tree
create_tmp_from_val (tree val, bool is_formal)
{
/* Drop all qualifiers and address-space information from the value type. */
tree type = TYPE_MAIN_VARIANT (TREE_TYPE (val));
tree var = create_tmp_var (type, get_name (val));
if (is_formal
&& (TREE_CODE (TREE_TYPE (var)) == COMPLEX_TYPE
|| TREE_CODE (TREE_TYPE (var)) == VECTOR_TYPE))
DECL_GIMPLE_REG_P (var) = 1;
return var;
}
/* Create a temporary to hold the value of VAL. If IS_FORMAL, try to reuse
an existing expression temporary. */
static tree
lookup_tmp_var (tree val, bool is_formal)
{
tree ret;
/* If not optimizing, never really reuse a temporary. local-alloc
won't allocate any variable that is used in more than one basic
block, which means it will go into memory, causing much extra
work in reload and final and poorer code generation, outweighing
the extra memory allocation here. */
if (!optimize || !is_formal || TREE_SIDE_EFFECTS (val))
ret = create_tmp_from_val (val, is_formal);
else
{
elt_t elt, *elt_p;
void **slot;
elt.val = val;
if (gimplify_ctxp->temp_htab == NULL)
gimplify_ctxp->temp_htab
= htab_create (1000, gimple_tree_hash, gimple_tree_eq, free);
slot = htab_find_slot (gimplify_ctxp->temp_htab, (void *)&elt, INSERT);
if (*slot == NULL)
{
elt_p = XNEW (elt_t);
elt_p->val = val;
elt_p->temp = ret = create_tmp_from_val (val, is_formal);
*slot = (void *) elt_p;
}
else
{
elt_p = (elt_t *) *slot;
ret = elt_p->temp;
}
}
return ret;
}
/* Helper for get_formal_tmp_var and get_initialized_tmp_var. */
static tree
internal_get_tmp_var (tree val, gimple_seq *pre_p, gimple_seq *post_p,
bool is_formal)
{
tree t, mod;
/* Notice that we explicitly allow VAL to be a CALL_EXPR so that we
can create an INIT_EXPR and convert it into a GIMPLE_CALL below. */
gimplify_expr (&val, pre_p, post_p, is_gimple_reg_rhs_or_call,
fb_rvalue);
if (gimplify_ctxp->into_ssa
&& is_gimple_reg_type (TREE_TYPE (val)))
t = make_ssa_name (TYPE_MAIN_VARIANT (TREE_TYPE (val)), NULL);
else
t = lookup_tmp_var (val, is_formal);
mod = build2 (INIT_EXPR, TREE_TYPE (t), t, unshare_expr (val));
SET_EXPR_LOCATION (mod, EXPR_LOC_OR_HERE (val));
/* gimplify_modify_expr might want to reduce this further. */
gimplify_and_add (mod, pre_p);
ggc_free (mod);
return t;
}
/* Return a formal temporary variable initialized with VAL. PRE_P is as
in gimplify_expr. Only use this function if:
1) The value of the unfactored expression represented by VAL will not
change between the initialization and use of the temporary, and
2) The temporary will not be otherwise modified.
For instance, #1 means that this is inappropriate for SAVE_EXPR temps,
and #2 means it is inappropriate for && temps.
For other cases, use get_initialized_tmp_var instead. */
tree
get_formal_tmp_var (tree val, gimple_seq *pre_p)
{
return internal_get_tmp_var (val, pre_p, NULL, true);
}
/* Return a temporary variable initialized with VAL. PRE_P and POST_P
are as in gimplify_expr. */
tree
get_initialized_tmp_var (tree val, gimple_seq *pre_p, gimple_seq *post_p)
{
return internal_get_tmp_var (val, pre_p, post_p, false);
}
/* Declare all the variables in VARS in SCOPE. If DEBUG_INFO is true,
generate debug info for them; otherwise don't. */
void
declare_vars (tree vars, gimple scope, bool debug_info)
{
tree last = vars;
if (last)
{
tree temps, block;
gcc_assert (gimple_code (scope) == GIMPLE_BIND);
temps = nreverse (last);
block = gimple_bind_block (scope);
gcc_assert (!block || TREE_CODE (block) == BLOCK);
if (!block || !debug_info)
{
DECL_CHAIN (last) = gimple_bind_vars (scope);
gimple_bind_set_vars (scope, temps);
}
else
{
/* We need to attach the nodes both to the BIND_EXPR and to its
associated BLOCK for debugging purposes. The key point here
is that the BLOCK_VARS of the BIND_EXPR_BLOCK of a BIND_EXPR
is a subchain of the BIND_EXPR_VARS of the BIND_EXPR. */
if (BLOCK_VARS (block))
BLOCK_VARS (block) = chainon (BLOCK_VARS (block), temps);
else
{
gimple_bind_set_vars (scope,
chainon (gimple_bind_vars (scope), temps));
BLOCK_VARS (block) = temps;
}
}
}
}
/* For VAR a VAR_DECL of variable size, try to find a constant upper bound
for the size and adjust DECL_SIZE/DECL_SIZE_UNIT accordingly. Abort if
no such upper bound can be obtained. */
static void
force_constant_size (tree var)
{
/* The only attempt we make is by querying the maximum size of objects
of the variable's type. */
HOST_WIDE_INT max_size;
gcc_assert (TREE_CODE (var) == VAR_DECL);
max_size = max_int_size_in_bytes (TREE_TYPE (var));
gcc_assert (max_size >= 0);
DECL_SIZE_UNIT (var)
= build_int_cst (TREE_TYPE (DECL_SIZE_UNIT (var)), max_size);
DECL_SIZE (var)
= build_int_cst (TREE_TYPE (DECL_SIZE (var)), max_size * BITS_PER_UNIT);
}
/* Push the temporary variable TMP into the current binding. */
void
gimple_add_tmp_var (tree tmp)
{
gcc_assert (!DECL_CHAIN (tmp) && !DECL_SEEN_IN_BIND_EXPR_P (tmp));
/* Later processing assumes that the object size is constant, which might
not be true at this point. Force the use of a constant upper bound in
this case. */
if (!host_integerp (DECL_SIZE_UNIT (tmp), 1))
force_constant_size (tmp);
DECL_CONTEXT (tmp) = current_function_decl;
DECL_SEEN_IN_BIND_EXPR_P (tmp) = 1;
if (gimplify_ctxp)
{
DECL_CHAIN (tmp) = gimplify_ctxp->temps;
gimplify_ctxp->temps = tmp;
/* Mark temporaries local within the nearest enclosing parallel. */
if (gimplify_omp_ctxp)
{
struct gimplify_omp_ctx *ctx = gimplify_omp_ctxp;
while (ctx && ctx->region_type == ORT_WORKSHARE)
ctx = ctx->outer_context;
if (ctx)
omp_add_variable (ctx, tmp, GOVD_LOCAL | GOVD_SEEN);
}
}
else if (cfun)
record_vars (tmp);
else
{
gimple_seq body_seq;
/* This case is for nested functions. We need to expose the locals
they create. */
body_seq = gimple_body (current_function_decl);
declare_vars (tmp, gimple_seq_first_stmt (body_seq), false);
}
}
/* Determine whether to assign a location to the statement GS. */
static bool
should_carry_location_p (gimple gs)
{
/* Don't emit a line note for a label. We particularly don't want to
emit one for the break label, since it doesn't actually correspond
to the beginning of the loop/switch. */
if (gimple_code (gs) == GIMPLE_LABEL)
return false;
return true;
}
/* Return true if a location should not be emitted for this statement
by annotate_one_with_location. */
static inline bool
gimple_do_not_emit_location_p (gimple g)
{
return gimple_plf (g, GF_PLF_1);
}
/* Mark statement G so a location will not be emitted by
annotate_one_with_location. */
static inline void
gimple_set_do_not_emit_location (gimple g)
{
/* The PLF flags are initialized to 0 when a new tuple is created,
so no need to initialize it anywhere. */
gimple_set_plf (g, GF_PLF_1, true);
}
/* Set the location for gimple statement GS to LOCATION. */
static void
annotate_one_with_location (gimple gs, location_t location)
{
if (!gimple_has_location (gs)
&& !gimple_do_not_emit_location_p (gs)
&& should_carry_location_p (gs))
gimple_set_location (gs, location);
}
/* Set LOCATION for all the statements after iterator GSI in sequence
SEQ. If GSI is pointing to the end of the sequence, start with the
first statement in SEQ. */
static void
annotate_all_with_location_after (gimple_seq seq, gimple_stmt_iterator gsi,
location_t location)
{
if (gsi_end_p (gsi))
gsi = gsi_start (seq);
else
gsi_next (&gsi);
for (; !gsi_end_p (gsi); gsi_next (&gsi))
annotate_one_with_location (gsi_stmt (gsi), location);
}
/* Set the location for all the statements in a sequence STMT_P to LOCATION. */
void
annotate_all_with_location (gimple_seq stmt_p, location_t location)
{
gimple_stmt_iterator i;
if (gimple_seq_empty_p (stmt_p))
return;
for (i = gsi_start (stmt_p); !gsi_end_p (i); gsi_next (&i))
{
gimple gs = gsi_stmt (i);
annotate_one_with_location (gs, location);
}
}
/* This page contains routines to unshare tree nodes, i.e. to duplicate tree
nodes that are referenced more than once in GENERIC functions. This is
necessary because gimplification (translation into GIMPLE) is performed
by modifying tree nodes in-place, so gimplication of a shared node in a
first context could generate an invalid GIMPLE form in a second context.
This is achieved with a simple mark/copy/unmark algorithm that walks the
GENERIC representation top-down, marks nodes with TREE_VISITED the first
time it encounters them, duplicates them if they already have TREE_VISITED
set, and finally removes the TREE_VISITED marks it has set.
The algorithm works only at the function level, i.e. it generates a GENERIC
representation of a function with no nodes shared within the function when
passed a GENERIC function (except for nodes that are allowed to be shared).
At the global level, it is also necessary to unshare tree nodes that are
referenced in more than one function, for the same aforementioned reason.
This requires some cooperation from the front-end. There are 2 strategies:
1. Manual unsharing. The front-end needs to call unshare_expr on every
expression that might end up being shared across functions.
2. Deep unsharing. This is an extension of regular unsharing. Instead
of calling unshare_expr on expressions that might be shared across
functions, the front-end pre-marks them with TREE_VISITED. This will
ensure that they are unshared on the first reference within functions
when the regular unsharing algorithm runs. The counterpart is that
this algorithm must look deeper than for manual unsharing, which is
specified by LANG_HOOKS_DEEP_UNSHARING.
If there are only few specific cases of node sharing across functions, it is
probably easier for a front-end to unshare the expressions manually. On the
contrary, if the expressions generated at the global level are as widespread
as expressions generated within functions, deep unsharing is very likely the
way to go. */
/* Similar to copy_tree_r but do not copy SAVE_EXPR or TARGET_EXPR nodes.
These nodes model computations that must be done once. If we were to
unshare something like SAVE_EXPR(i++), the gimplification process would
create wrong code. However, if DATA is non-null, it must hold a pointer
set that is used to unshare the subtrees of these nodes. */
static tree
mostly_copy_tree_r (tree *tp, int *walk_subtrees, void *data)
{
tree t = *tp;
enum tree_code code = TREE_CODE (t);
/* Do not copy SAVE_EXPR, TARGET_EXPR or BIND_EXPR nodes themselves, but
copy their subtrees if we can make sure to do it only once. */
if (code == SAVE_EXPR || code == TARGET_EXPR || code == BIND_EXPR)
{
if (data && !pointer_set_insert ((struct pointer_set_t *)data, t))
;
else
*walk_subtrees = 0;
}
/* Stop at types, decls, constants like copy_tree_r. */
else if (TREE_CODE_CLASS (code) == tcc_type
|| TREE_CODE_CLASS (code) == tcc_declaration
|| TREE_CODE_CLASS (code) == tcc_constant
/* We can't do anything sensible with a BLOCK used as an
expression, but we also can't just die when we see it
because of non-expression uses. So we avert our eyes
and cross our fingers. Silly Java. */
|| code == BLOCK)
*walk_subtrees = 0;
/* Cope with the statement expression extension. */
else if (code == STATEMENT_LIST)
;
/* Leave the bulk of the work to copy_tree_r itself. */
else
copy_tree_r (tp, walk_subtrees, NULL);
return NULL_TREE;
}
/* Callback for walk_tree to unshare most of the shared trees rooted at *TP.
If *TP has been visited already, then *TP is deeply copied by calling
mostly_copy_tree_r. DATA is passed to mostly_copy_tree_r unmodified. */
static tree
copy_if_shared_r (tree *tp, int *walk_subtrees, void *data)
{
tree t = *tp;
enum tree_code code = TREE_CODE (t);
/* Skip types, decls, and constants. But we do want to look at their
types and the bounds of types. Mark them as visited so we properly
unmark their subtrees on the unmark pass. If we've already seen them,
don't look down further. */
if (TREE_CODE_CLASS (code) == tcc_type
|| TREE_CODE_CLASS (code) == tcc_declaration
|| TREE_CODE_CLASS (code) == tcc_constant)
{
if (TREE_VISITED (t))
*walk_subtrees = 0;
else
TREE_VISITED (t) = 1;
}
/* If this node has been visited already, unshare it and don't look
any deeper. */
else if (TREE_VISITED (t))
{
walk_tree (tp, mostly_copy_tree_r, data, NULL);
*walk_subtrees = 0;
}
/* Otherwise, mark the node as visited and keep looking. */
else
TREE_VISITED (t) = 1;
return NULL_TREE;
}
/* Unshare most of the shared trees rooted at *TP. DATA is passed to the
copy_if_shared_r callback unmodified. */
static inline void
copy_if_shared (tree *tp, void *data)
{
walk_tree (tp, copy_if_shared_r, data, NULL);
}
/* Unshare all the trees in the body of FNDECL, as well as in the bodies of
any nested functions. */
static void
unshare_body (tree fndecl)
{
struct cgraph_node *cgn = cgraph_get_node (fndecl);
/* If the language requires deep unsharing, we need a pointer set to make
sure we don't repeatedly unshare subtrees of unshareable nodes. */
struct pointer_set_t *visited
= lang_hooks.deep_unsharing ? pointer_set_create () : NULL;
copy_if_shared (&DECL_SAVED_TREE (fndecl), visited);
copy_if_shared (&DECL_SIZE (DECL_RESULT (fndecl)), visited);
copy_if_shared (&DECL_SIZE_UNIT (DECL_RESULT (fndecl)), visited);
if (visited)
pointer_set_destroy (visited);
if (cgn)
for (cgn = cgn->nested; cgn; cgn = cgn->next_nested)
unshare_body (cgn->symbol.decl);
}
/* Callback for walk_tree to unmark the visited trees rooted at *TP.
Subtrees are walked until the first unvisited node is encountered. */
static tree
unmark_visited_r (tree *tp, int *walk_subtrees, void *data ATTRIBUTE_UNUSED)
{
tree t = *tp;
/* If this node has been visited, unmark it and keep looking. */
if (TREE_VISITED (t))
TREE_VISITED (t) = 0;
/* Otherwise, don't look any deeper. */
else
*walk_subtrees = 0;
return NULL_TREE;
}
/* Unmark the visited trees rooted at *TP. */
static inline void
unmark_visited (tree *tp)
{
walk_tree (tp, unmark_visited_r, NULL, NULL);
}
/* Likewise, but mark all trees as not visited. */
static void
unvisit_body (tree fndecl)
{
struct cgraph_node *cgn = cgraph_get_node (fndecl);
unmark_visited (&DECL_SAVED_TREE (fndecl));
unmark_visited (&DECL_SIZE (DECL_RESULT (fndecl)));
unmark_visited (&DECL_SIZE_UNIT (DECL_RESULT (fndecl)));
if (cgn)
for (cgn = cgn->nested; cgn; cgn = cgn->next_nested)
unvisit_body (cgn->symbol.decl);
}
/* Unconditionally make an unshared copy of EXPR. This is used when using
stored expressions which span multiple functions, such as BINFO_VTABLE,
as the normal unsharing process can't tell that they're shared. */
tree
unshare_expr (tree expr)
{
walk_tree (&expr, mostly_copy_tree_r, NULL, NULL);
return expr;
}
/* Worker for unshare_expr_without_location. */
static tree
prune_expr_location (tree *tp, int *walk_subtrees, void *)
{
if (EXPR_P (*tp))
SET_EXPR_LOCATION (*tp, UNKNOWN_LOCATION);
else
*walk_subtrees = 0;
return NULL_TREE;
}
/* Similar to unshare_expr but also prune all expression locations
from EXPR. */
tree
unshare_expr_without_location (tree expr)
{
walk_tree (&expr, mostly_copy_tree_r, NULL, NULL);
if (EXPR_P (expr))
walk_tree (&expr, prune_expr_location, NULL, NULL);
return expr;
}
/* WRAPPER is a code such as BIND_EXPR or CLEANUP_POINT_EXPR which can both
contain statements and have a value. Assign its value to a temporary
and give it void_type_node. Return the temporary, or NULL_TREE if
WRAPPER was already void. */
tree
voidify_wrapper_expr (tree wrapper, tree temp)
{
tree type = TREE_TYPE (wrapper);
if (type && !VOID_TYPE_P (type))
{
tree *p;
/* Set p to point to the body of the wrapper. Loop until we find
something that isn't a wrapper. */
for (p = &wrapper; p && *p; )
{
switch (TREE_CODE (*p))
{
case BIND_EXPR:
TREE_SIDE_EFFECTS (*p) = 1;
TREE_TYPE (*p) = void_type_node;
/* For a BIND_EXPR, the body is operand 1. */
p = &BIND_EXPR_BODY (*p);
break;
case CLEANUP_POINT_EXPR:
case TRY_FINALLY_EXPR:
case TRY_CATCH_EXPR:
TREE_SIDE_EFFECTS (*p) = 1;
TREE_TYPE (*p) = void_type_node;
p = &TREE_OPERAND (*p, 0);
break;
case STATEMENT_LIST:
{
tree_stmt_iterator i = tsi_last (*p);
TREE_SIDE_EFFECTS (*p) = 1;
TREE_TYPE (*p) = void_type_node;
p = tsi_end_p (i) ? NULL : tsi_stmt_ptr (i);
}
break;
case COMPOUND_EXPR:
/* Advance to the last statement. Set all container types to
void. */
for (; TREE_CODE (*p) == COMPOUND_EXPR; p = &TREE_OPERAND (*p, 1))
{
TREE_SIDE_EFFECTS (*p) = 1;
TREE_TYPE (*p) = void_type_node;
}
break;
case TRANSACTION_EXPR:
TREE_SIDE_EFFECTS (*p) = 1;
TREE_TYPE (*p) = void_type_node;
p = &TRANSACTION_EXPR_BODY (*p);
break;
default:
/* Assume that any tree upon which voidify_wrapper_expr is
directly called is a wrapper, and that its body is op0. */
if (p == &wrapper)
{
TREE_SIDE_EFFECTS (*p) = 1;
TREE_TYPE (*p) = void_type_node;
p = &TREE_OPERAND (*p, 0);
break;
}
goto out;
}
}
out:
if (p == NULL || IS_EMPTY_STMT (*p))
temp = NULL_TREE;
else if (temp)
{
/* The wrapper is on the RHS of an assignment that we're pushing
down. */
gcc_assert (TREE_CODE (temp) == INIT_EXPR
|| TREE_CODE (temp) == MODIFY_EXPR);
TREE_OPERAND (temp, 1) = *p;
*p = temp;
}
else
{
temp = create_tmp_var (type, "retval");
*p = build2 (INIT_EXPR, type, temp, *p);
}
return temp;
}
return NULL_TREE;
}
/* Prepare calls to builtins to SAVE and RESTORE the stack as well as
a temporary through which they communicate. */
static void
build_stack_save_restore (gimple *save, gimple *restore)
{
tree tmp_var;
*save = gimple_build_call (builtin_decl_implicit (BUILT_IN_STACK_SAVE), 0);
tmp_var = create_tmp_var (ptr_type_node, "saved_stack");
gimple_call_set_lhs (*save, tmp_var);
*restore
= gimple_build_call (builtin_decl_implicit (BUILT_IN_STACK_RESTORE),
1, tmp_var);
}
/* Gimplify a BIND_EXPR. Just voidify and recurse. */
static enum gimplify_status
gimplify_bind_expr (tree *expr_p, gimple_seq *pre_p)
{
tree bind_expr = *expr_p;
bool old_save_stack = gimplify_ctxp->save_stack;
tree t;
gimple gimple_bind;
gimple_seq body, cleanup;
gimple stack_save;
tree temp = voidify_wrapper_expr (bind_expr, NULL);
/* Mark variables seen in this bind expr. */
for (t = BIND_EXPR_VARS (bind_expr); t ; t = DECL_CHAIN (t))
{
if (TREE_CODE (t) == VAR_DECL)
{
struct gimplify_omp_ctx *ctx = gimplify_omp_ctxp;
/* Mark variable as local. */
if (ctx && !DECL_EXTERNAL (t)
&& (! DECL_SEEN_IN_BIND_EXPR_P (t)
|| splay_tree_lookup (ctx->variables,
(splay_tree_key) t) == NULL))
omp_add_variable (gimplify_omp_ctxp, t, GOVD_LOCAL | GOVD_SEEN);
DECL_SEEN_IN_BIND_EXPR_P (t) = 1;
if (DECL_HARD_REGISTER (t) && !is_global_var (t) && cfun)
cfun->has_local_explicit_reg_vars = true;
}
/* Preliminarily mark non-addressed complex variables as eligible
for promotion to gimple registers. We'll transform their uses
as we find them. */
if ((TREE_CODE (TREE_TYPE (t)) == COMPLEX_TYPE
|| TREE_CODE (TREE_TYPE (t)) == VECTOR_TYPE)
&& !TREE_THIS_VOLATILE (t)
&& (TREE_CODE (t) == VAR_DECL && !DECL_HARD_REGISTER (t))
&& !needs_to_live_in_memory (t))
DECL_GIMPLE_REG_P (t) = 1;
}
gimple_bind = gimple_build_bind (BIND_EXPR_VARS (bind_expr), NULL,
BIND_EXPR_BLOCK (bind_expr));
gimple_push_bind_expr (gimple_bind);
gimplify_ctxp->save_stack = false;
/* Gimplify the body into the GIMPLE_BIND tuple's body. */
body = NULL;
gimplify_stmt (&BIND_EXPR_BODY (bind_expr), &body);
gimple_bind_set_body (gimple_bind, body);
cleanup = NULL;
stack_save = NULL;
if (gimplify_ctxp->save_stack)
{
gimple stack_restore;
/* Save stack on entry and restore it on exit. Add a try_finally
block to achieve this. Note that mudflap depends on the
format of the emitted code: see mx_register_decls(). */
build_stack_save_restore (&stack_save, &stack_restore);
gimplify_seq_add_stmt (&cleanup, stack_restore);
}
/* Add clobbers for all variables that go out of scope. */
for (t = BIND_EXPR_VARS (bind_expr); t ; t = DECL_CHAIN (t))
{
if (TREE_CODE (t) == VAR_DECL
&& !is_global_var (t)
&& DECL_CONTEXT (t) == current_function_decl
&& !DECL_HARD_REGISTER (t)
&& !TREE_THIS_VOLATILE (t)
&& !DECL_HAS_VALUE_EXPR_P (t)
/* Only care for variables that have to be in memory. Others
will be rewritten into SSA names, hence moved to the top-level. */
&& !is_gimple_reg (t)
&& flag_stack_reuse != SR_NONE)
{
tree clobber = build_constructor (TREE_TYPE (t),
NULL);
TREE_THIS_VOLATILE (clobber) = 1;
gimplify_seq_add_stmt (&cleanup, gimple_build_assign (t, clobber));
}
}
if (cleanup)
{
gimple gs;
gimple_seq new_body;
new_body = NULL;
gs = gimple_build_try (gimple_bind_body (gimple_bind), cleanup,
GIMPLE_TRY_FINALLY);
if (stack_save)
gimplify_seq_add_stmt (&new_body, stack_save);
gimplify_seq_add_stmt (&new_body, gs);
gimple_bind_set_body (gimple_bind, new_body);
}
gimplify_ctxp->save_stack = old_save_stack;
gimple_pop_bind_expr ();
gimplify_seq_add_stmt (pre_p, gimple_bind);
if (temp)
{
*expr_p = temp;
return GS_OK;
}
*expr_p = NULL_TREE;
return GS_ALL_DONE;
}
/* Gimplify a RETURN_EXPR. If the expression to be returned is not a
GIMPLE value, it is assigned to a new temporary and the statement is
re-written to return the temporary.
PRE_P points to the sequence where side effects that must happen before
STMT should be stored. */
static enum gimplify_status
gimplify_return_expr (tree stmt, gimple_seq *pre_p)
{
gimple ret;
tree ret_expr = TREE_OPERAND (stmt, 0);
tree result_decl, result;
if (ret_expr == error_mark_node)
return GS_ERROR;
if (!ret_expr
|| TREE_CODE (ret_expr) == RESULT_DECL
|| ret_expr == error_mark_node)
{
gimple ret = gimple_build_return (ret_expr);
gimple_set_no_warning (ret, TREE_NO_WARNING (stmt));
gimplify_seq_add_stmt (pre_p, ret);
return GS_ALL_DONE;
}
if (VOID_TYPE_P (TREE_TYPE (TREE_TYPE (current_function_decl))))
result_decl = NULL_TREE;
else
{
result_decl = TREE_OPERAND (ret_expr, 0);
/* See through a return by reference. */
if (TREE_CODE (result_decl) == INDIRECT_REF)
result_decl = TREE_OPERAND (result_decl, 0);
gcc_assert ((TREE_CODE (ret_expr) == MODIFY_EXPR
|| TREE_CODE (ret_expr) == INIT_EXPR)
&& TREE_CODE (result_decl) == RESULT_DECL);
}
/* If aggregate_value_p is true, then we can return the bare RESULT_DECL.
Recall that aggregate_value_p is FALSE for any aggregate type that is
returned in registers. If we're returning values in registers, then
we don't want to extend the lifetime of the RESULT_DECL, particularly
across another call. In addition, for those aggregates for which
hard_function_value generates a PARALLEL, we'll die during normal
expansion of structure assignments; there's special code in expand_return
to handle this case that does not exist in expand_expr. */
if (!result_decl)
result = NULL_TREE;
else if (aggregate_value_p (result_decl, TREE_TYPE (current_function_decl)))
{
if (TREE_CODE (DECL_SIZE (result_decl)) != INTEGER_CST)
{
if (!TYPE_SIZES_GIMPLIFIED (TREE_TYPE (result_decl)))
gimplify_type_sizes (TREE_TYPE (result_decl), pre_p);
/* Note that we don't use gimplify_vla_decl because the RESULT_DECL
should be effectively allocated by the caller, i.e. all calls to
this function must be subject to the Return Slot Optimization. */
gimplify_one_sizepos (&DECL_SIZE (result_decl), pre_p);
gimplify_one_sizepos (&DECL_SIZE_UNIT (result_decl), pre_p);
}
result = result_decl;
}
else if (gimplify_ctxp->return_temp)
result = gimplify_ctxp->return_temp;
else
{
result = create_tmp_reg (TREE_TYPE (result_decl), NULL);
/* ??? With complex control flow (usually involving abnormal edges),
we can wind up warning about an uninitialized value for this. Due
to how this variable is constructed and initialized, this is never
true. Give up and never warn. */
TREE_NO_WARNING (result) = 1;
gimplify_ctxp->return_temp = result;
}
/* Smash the lhs of the MODIFY_EXPR to the temporary we plan to use.
Then gimplify the whole thing. */
if (result != result_decl)
TREE_OPERAND (ret_expr, 0) = result;
gimplify_and_add (TREE_OPERAND (stmt, 0), pre_p);
ret = gimple_build_return (result);
gimple_set_no_warning (ret, TREE_NO_WARNING (stmt));
gimplify_seq_add_stmt (pre_p, ret);
return GS_ALL_DONE;
}
/* Gimplify a variable-length array DECL. */
static void
gimplify_vla_decl (tree decl, gimple_seq *seq_p)
{
/* This is a variable-sized decl. Simplify its size and mark it
for deferred expansion. Note that mudflap depends on the format
of the emitted code: see mx_register_decls(). */
tree t, addr, ptr_type;
gimplify_one_sizepos (&DECL_SIZE (decl), seq_p);
gimplify_one_sizepos (&DECL_SIZE_UNIT (decl), seq_p);
/* All occurrences of this decl in final gimplified code will be
replaced by indirection. Setting DECL_VALUE_EXPR does two
things: First, it lets the rest of the gimplifier know what
replacement to use. Second, it lets the debug info know
where to find the value. */
ptr_type = build_pointer_type (TREE_TYPE (decl));
addr = create_tmp_var (ptr_type, get_name (decl));
DECL_IGNORED_P (addr) = 0;
t = build_fold_indirect_ref (addr);
TREE_THIS_NOTRAP (t) = 1;
SET_DECL_VALUE_EXPR (decl, t);
DECL_HAS_VALUE_EXPR_P (decl) = 1;
t = builtin_decl_explicit (BUILT_IN_ALLOCA_WITH_ALIGN);
t = build_call_expr (t, 2, DECL_SIZE_UNIT (decl),
size_int (DECL_ALIGN (decl)));
/* The call has been built for a variable-sized object. */
CALL_ALLOCA_FOR_VAR_P (t) = 1;
t = fold_convert (ptr_type, t);
t = build2 (MODIFY_EXPR, TREE_TYPE (addr), addr, t);
gimplify_and_add (t, seq_p);
/* Indicate that we need to restore the stack level when the
enclosing BIND_EXPR is exited. */
gimplify_ctxp->save_stack = true;
}
/* Gimplify a DECL_EXPR node *STMT_P by making any necessary allocation
and initialization explicit. */
static enum gimplify_status
gimplify_decl_expr (tree *stmt_p, gimple_seq *seq_p)
{
tree stmt = *stmt_p;
tree decl = DECL_EXPR_DECL (stmt);
*stmt_p = NULL_TREE;
if (TREE_TYPE (decl) == error_mark_node)
return GS_ERROR;
if ((TREE_CODE (decl) == TYPE_DECL
|| TREE_CODE (decl) == VAR_DECL)
&& !TYPE_SIZES_GIMPLIFIED (TREE_TYPE (decl)))
gimplify_type_sizes (TREE_TYPE (decl), seq_p);
/* ??? DECL_ORIGINAL_TYPE is streamed for LTO so it needs to be gimplified
in case its size expressions contain problematic nodes like CALL_EXPR. */
if (TREE_CODE (decl) == TYPE_DECL
&& DECL_ORIGINAL_TYPE (decl)
&& !TYPE_SIZES_GIMPLIFIED (DECL_ORIGINAL_TYPE (decl)))
gimplify_type_sizes (DECL_ORIGINAL_TYPE (decl), seq_p);
if (TREE_CODE (decl) == VAR_DECL && !DECL_EXTERNAL (decl))
{
tree init = DECL_INITIAL (decl);
if (TREE_CODE (DECL_SIZE_UNIT (decl)) != INTEGER_CST
|| (!TREE_STATIC (decl)
&& flag_stack_check == GENERIC_STACK_CHECK
&& compare_tree_int (DECL_SIZE_UNIT (decl),
STACK_CHECK_MAX_VAR_SIZE) > 0))
gimplify_vla_decl (decl, seq_p);
/* Some front ends do not explicitly declare all anonymous
artificial variables. We compensate here by declaring the
variables, though it would be better if the front ends would
explicitly declare them. */
if (!DECL_SEEN_IN_BIND_EXPR_P (decl)
&& DECL_ARTIFICIAL (decl) && DECL_NAME (decl) == NULL_TREE)
gimple_add_tmp_var (decl);
if (init && init != error_mark_node)
{
if (!TREE_STATIC (decl))
{
DECL_INITIAL (decl) = NULL_TREE;
init = build2 (INIT_EXPR, void_type_node, decl, init);
gimplify_and_add (init, seq_p);
ggc_free (init);
}
else
/* We must still examine initializers for static variables
as they may contain a label address. */
walk_tree (&init, force_labels_r, NULL, NULL);
}
}
return GS_ALL_DONE;
}
/* Gimplify a LOOP_EXPR. Normally this just involves gimplifying the body
and replacing the LOOP_EXPR with goto, but if the loop contains an
EXIT_EXPR, we need to append a label for it to jump to. */
static enum gimplify_status
gimplify_loop_expr (tree *expr_p, gimple_seq *pre_p)
{
tree saved_label = gimplify_ctxp->exit_label;
tree start_label = create_artificial_label (UNKNOWN_LOCATION);
gimplify_seq_add_stmt (pre_p, gimple_build_label (start_label));
gimplify_ctxp->exit_label = NULL_TREE;
gimplify_and_add (LOOP_EXPR_BODY (*expr_p), pre_p);
gimplify_seq_add_stmt (pre_p, gimple_build_goto (start_label));
if (gimplify_ctxp->exit_label)
gimplify_seq_add_stmt (pre_p,
gimple_build_label (gimplify_ctxp->exit_label));
gimplify_ctxp->exit_label = saved_label;
*expr_p = NULL;
return GS_ALL_DONE;
}
/* Gimplify a statement list onto a sequence. These may be created either
by an enlightened front-end, or by shortcut_cond_expr. */
static enum gimplify_status
gimplify_statement_list (tree *expr_p, gimple_seq *pre_p)
{
tree temp = voidify_wrapper_expr (*expr_p, NULL);
tree_stmt_iterator i = tsi_start (*expr_p);
while (!tsi_end_p (i))
{
gimplify_stmt (tsi_stmt_ptr (i), pre_p);
tsi_delink (&i);
}
if (temp)
{
*expr_p = temp;
return GS_OK;
}
return GS_ALL_DONE;
}
/* Compare two case labels. Because the front end should already have
made sure that case ranges do not overlap, it is enough to only compare
the CASE_LOW values of each case label. */
static int
compare_case_labels (const void *p1, const void *p2)
{
const_tree const case1 = *(const_tree const*)p1;
const_tree const case2 = *(const_tree const*)p2;
/* The 'default' case label always goes first. */
if (!CASE_LOW (case1))
return -1;
else if (!CASE_LOW (case2))
return 1;
else
return tree_int_cst_compare (CASE_LOW (case1), CASE_LOW (case2));
}
/* Sort the case labels in LABEL_VEC in place in ascending order. */
void
sort_case_labels (vec<tree> label_vec)
{
label_vec.qsort (compare_case_labels);
}
/* Prepare a vector of case labels to be used in a GIMPLE_SWITCH statement.
LABELS is a vector that contains all case labels to look at.
INDEX_TYPE is the type of the switch index expression. Case labels
in LABELS are discarded if their values are not in the value range
covered by INDEX_TYPE. The remaining case label values are folded
to INDEX_TYPE.
If a default case exists in LABELS, it is removed from LABELS and
returned in DEFAULT_CASEP. If no default case exists, but the
case labels already cover the whole range of INDEX_TYPE, a default
case is returned pointing to one of the existing case labels.
Otherwise DEFAULT_CASEP is set to NULL_TREE.
DEFAULT_CASEP may be NULL, in which case the above comment doesn't
apply and no action is taken regardless of whether a default case is
found or not. */
void
preprocess_case_label_vec_for_gimple (vec<tree> labels,
tree index_type,
tree *default_casep)
{
tree min_value, max_value;
tree default_case = NULL_TREE;
size_t i, len;
i = 0;
min_value = TYPE_MIN_VALUE (index_type);
max_value = TYPE_MAX_VALUE (index_type);
while (i < labels.length ())
{
tree elt = labels[i];
tree low = CASE_LOW (elt);
tree high = CASE_HIGH (elt);
bool remove_element = FALSE;
if (low)
{
gcc_checking_assert (TREE_CODE (low) == INTEGER_CST);
gcc_checking_assert (!high || TREE_CODE (high) == INTEGER_CST);
/* This is a non-default case label, i.e. it has a value.
See if the case label is reachable within the range of
the index type. Remove out-of-range case values. Turn
case ranges into a canonical form (high > low strictly)
and convert the case label values to the index type.
NB: The type of gimple_switch_index() may be the promoted
type, but the case labels retain the original type. */
if (high)
{
/* This is a case range. Discard empty ranges.
If the bounds or the range are equal, turn this
into a simple (one-value) case. */
int cmp = tree_int_cst_compare (high, low);
if (cmp < 0)
remove_element = TRUE;
else if (cmp == 0)
high = NULL_TREE;
}
if (! high)
{
/* If the simple case value is unreachable, ignore it. */
if ((TREE_CODE (min_value) == INTEGER_CST
&& tree_int_cst_compare (low, min_value) < 0)
|| (TREE_CODE (max_value) == INTEGER_CST
&& tree_int_cst_compare (low, max_value) > 0))
remove_element = TRUE;
else
low = fold_convert (index_type, low);
}
else
{
/* If the entire case range is unreachable, ignore it. */
if ((TREE_CODE (min_value) == INTEGER_CST
&& tree_int_cst_compare (high, min_value) < 0)
|| (TREE_CODE (max_value) == INTEGER_CST
&& tree_int_cst_compare (low, max_value) > 0))
remove_element = TRUE;
else
{
/* If the lower bound is less than the index type's
minimum value, truncate the range bounds. */
if (TREE_CODE (min_value) == INTEGER_CST
&& tree_int_cst_compare (low, min_value) < 0)
low = min_value;
low = fold_convert (index_type, low);
/* If the upper bound is greater than the index type's
maximum value, truncate the range bounds. */
if (TREE_CODE (max_value) == INTEGER_CST
&& tree_int_cst_compare (high, max_value) > 0)
high = max_value;
high = fold_convert (index_type, high);
/* We may have folded a case range to a one-value case. */
if (tree_int_cst_equal (low, high))
high = NULL_TREE;
}
}
CASE_LOW (elt) = low;
CASE_HIGH (elt) = high;
}
else
{
gcc_assert (!default_case);
default_case = elt;
/* The default case must be passed separately to the
gimple_build_switch routine. But if DEFAULT_CASEP
is NULL, we do not remove the default case (it would
be completely lost). */
if (default_casep)
remove_element = TRUE;
}
if (remove_element)
labels.ordered_remove (i);
else
i++;
}
len = i;
if (!labels.is_empty ())
sort_case_labels (labels);
if (default_casep && !default_case)
{
/* If the switch has no default label, add one, so that we jump
around the switch body. If the labels already cover the whole
range of the switch index_type, add the default label pointing
to one of the existing labels. */
if (len
&& TYPE_MIN_VALUE (index_type)
&& TYPE_MAX_VALUE (index_type)
&& tree_int_cst_equal (CASE_LOW (labels[0]),
TYPE_MIN_VALUE (index_type)))
{
tree low, high = CASE_HIGH (labels[len - 1]);
if (!high)
high = CASE_LOW (labels[len - 1]);
if (tree_int_cst_equal (high, TYPE_MAX_VALUE (index_type)))
{
for (i = 1; i < len; i++)
{
high = CASE_LOW (labels[i]);
low = CASE_HIGH (labels[i - 1]);
if (!low)
low = CASE_LOW (labels[i - 1]);
if ((TREE_INT_CST_LOW (low) + 1
!= TREE_INT_CST_LOW (high))
|| (TREE_INT_CST_HIGH (low)
+ (TREE_INT_CST_LOW (high) == 0)
!= TREE_INT_CST_HIGH (high)))
break;
}
if (i == len)
{
tree label = CASE_LABEL (labels[0]);
default_case = build_case_label (NULL_TREE, NULL_TREE,
label);
}
}
}
}
if (default_casep)
*default_casep = default_case;
}
/* Gimplify a SWITCH_EXPR, and collect the vector of labels it can
branch to. */
static enum gimplify_status
gimplify_switch_expr (tree *expr_p, gimple_seq *pre_p)
{
tree switch_expr = *expr_p;
gimple_seq switch_body_seq = NULL;
enum gimplify_status ret;
tree index_type = TREE_TYPE (switch_expr);
if (index_type == NULL_TREE)
index_type = TREE_TYPE (SWITCH_COND (switch_expr));
ret = gimplify_expr (&SWITCH_COND (switch_expr), pre_p, NULL, is_gimple_val,
fb_rvalue);
if (ret == GS_ERROR || ret == GS_UNHANDLED)
return ret;
if (SWITCH_BODY (switch_expr))
{
vec<tree> labels;
vec<tree> saved_labels;
tree default_case = NULL_TREE;
gimple gimple_switch;
/* If someone can be bothered to fill in the labels, they can
be bothered to null out the body too. */
gcc_assert (!SWITCH_LABELS (switch_expr));
/* Save old labels, get new ones from body, then restore the old
labels. Save all the things from the switch body to append after. */
saved_labels = gimplify_ctxp->case_labels;
gimplify_ctxp->case_labels.create (8);
gimplify_stmt (&SWITCH_BODY (switch_expr), &switch_body_seq);
labels = gimplify_ctxp->case_labels;
gimplify_ctxp->case_labels = saved_labels;
preprocess_case_label_vec_for_gimple (labels, index_type,
&default_case);
if (!default_case)
{
gimple new_default;
default_case
= build_case_label (NULL_TREE, NULL_TREE,
create_artificial_label (UNKNOWN_LOCATION));
new_default = gimple_build_label (CASE_LABEL (default_case));
gimplify_seq_add_stmt (&switch_body_seq, new_default);
}
gimple_switch = gimple_build_switch (SWITCH_COND (switch_expr),
default_case, labels);
gimplify_seq_add_stmt (pre_p, gimple_switch);
gimplify_seq_add_seq (pre_p, switch_body_seq);
labels.release ();
}
else
gcc_assert (SWITCH_LABELS (switch_expr));
return GS_ALL_DONE;
}
/* Gimplify the CASE_LABEL_EXPR pointed to by EXPR_P. */
static enum gimplify_status
gimplify_case_label_expr (tree *expr_p, gimple_seq *pre_p)
{
struct gimplify_ctx *ctxp;
gimple gimple_label;
/* Invalid OpenMP programs can play Duff's Device type games with
#pragma omp parallel. At least in the C front end, we don't
detect such invalid branches until after gimplification. */
for (ctxp = gimplify_ctxp; ; ctxp = ctxp->prev_context)
if (ctxp->case_labels.exists ())
break;
gimple_label = gimple_build_label (CASE_LABEL (*expr_p));
ctxp->case_labels.safe_push (*expr_p);
gimplify_seq_add_stmt (pre_p, gimple_label);
return GS_ALL_DONE;
}
/* Build a GOTO to the LABEL_DECL pointed to by LABEL_P, building it first
if necessary. */
tree
build_and_jump (tree *label_p)
{
if (label_p == NULL)
/* If there's nowhere to jump, just fall through. */
return NULL_TREE;
if (*label_p == NULL_TREE)
{
tree label = create_artificial_label (UNKNOWN_LOCATION);
*label_p = label;
}
return build1 (GOTO_EXPR, void_type_node, *label_p);
}
/* Gimplify an EXIT_EXPR by converting to a GOTO_EXPR inside a COND_EXPR.
This also involves building a label to jump to and communicating it to
gimplify_loop_expr through gimplify_ctxp->exit_label. */
static enum gimplify_status
gimplify_exit_expr (tree *expr_p)
{
tree cond = TREE_OPERAND (*expr_p, 0);
tree expr;
expr = build_and_jump (&gimplify_ctxp->exit_label);
expr = build3 (COND_EXPR, void_type_node, cond, expr, NULL_TREE);
*expr_p = expr;
return GS_OK;
}
/* A helper function to be called via walk_tree. Mark all labels under *TP
as being forced. To be called for DECL_INITIAL of static variables. */
tree
force_labels_r (tree *tp, int *walk_subtrees, void *data ATTRIBUTE_UNUSED)
{
if (TYPE_P (*tp))
*walk_subtrees = 0;
if (TREE_CODE (*tp) == LABEL_DECL)
FORCED_LABEL (*tp) = 1;
return NULL_TREE;
}
/* *EXPR_P is a COMPONENT_REF being used as an rvalue. If its type is
different from its canonical type, wrap the whole thing inside a
NOP_EXPR and force the type of the COMPONENT_REF to be the canonical
type.
The canonical type of a COMPONENT_REF is the type of the field being
referenced--unless the field is a bit-field which can be read directly
in a smaller mode, in which case the canonical type is the
sign-appropriate type corresponding to that mode. */
static void
canonicalize_component_ref (tree *expr_p)
{
tree expr = *expr_p;
tree type;
gcc_assert (TREE_CODE (expr) == COMPONENT_REF);
if (INTEGRAL_TYPE_P (TREE_TYPE (expr)))
type = TREE_TYPE (get_unwidened (expr, NULL_TREE));
else
type = TREE_TYPE (TREE_OPERAND (expr, 1));
/* One could argue that all the stuff below is not necessary for
the non-bitfield case and declare it a FE error if type
adjustment would be needed. */
if (TREE_TYPE (expr) != type)
{
#ifdef ENABLE_TYPES_CHECKING
tree old_type = TREE_TYPE (expr);
#endif
int type_quals;
/* We need to preserve qualifiers and propagate them from
operand 0. */
type_quals = TYPE_QUALS (type)
| TYPE_QUALS (TREE_TYPE (TREE_OPERAND (expr, 0)));
if (TYPE_QUALS (type) != type_quals)
type = build_qualified_type (TYPE_MAIN_VARIANT (type), type_quals);
/* Set the type of the COMPONENT_REF to the underlying type. */
TREE_TYPE (expr) = type;
#ifdef ENABLE_TYPES_CHECKING
/* It is now a FE error, if the conversion from the canonical
type to the original expression type is not useless. */
gcc_assert (useless_type_conversion_p (old_type, type));
#endif
}
}
/* If a NOP conversion is changing a pointer to array of foo to a pointer
to foo, embed that change in the ADDR_EXPR by converting
T array[U];
(T *)&array
==>
&array[L]
where L is the lower bound. For simplicity, only do this for constant
lower bound.
The constraint is that the type of &array[L] is trivially convertible
to T *. */
static void
canonicalize_addr_expr (tree *expr_p)
{
tree expr = *expr_p;
tree addr_expr = TREE_OPERAND (expr, 0);
tree datype, ddatype, pddatype;
/* We simplify only conversions from an ADDR_EXPR to a pointer type. */
if (!POINTER_TYPE_P (TREE_TYPE (expr))
|| TREE_CODE (addr_expr) != ADDR_EXPR)
return;
/* The addr_expr type should be a pointer to an array. */
datype = TREE_TYPE (TREE_TYPE (addr_expr));
if (TREE_CODE (datype) != ARRAY_TYPE)
return;
/* The pointer to element type shall be trivially convertible to
the expression pointer type. */
ddatype = TREE_TYPE (datype);
pddatype = build_pointer_type (ddatype);
if (!useless_type_conversion_p (TYPE_MAIN_VARIANT (TREE_TYPE (expr)),
pddatype))
return;
/* The lower bound and element sizes must be constant. */
if (!TYPE_SIZE_UNIT (ddatype)
|| TREE_CODE (TYPE_SIZE_UNIT (ddatype)) != INTEGER_CST
|| !TYPE_DOMAIN (datype) || !TYPE_MIN_VALUE (TYPE_DOMAIN (datype))
|| TREE_CODE (TYPE_MIN_VALUE (TYPE_DOMAIN (datype))) != INTEGER_CST)
return;
/* All checks succeeded. Build a new node to merge the cast. */
*expr_p = build4 (ARRAY_REF, ddatype, TREE_OPERAND (addr_expr, 0),
TYPE_MIN_VALUE (TYPE_DOMAIN (datype)),
NULL_TREE, NULL_TREE);
*expr_p = build1 (ADDR_EXPR, pddatype, *expr_p);
/* We can have stripped a required restrict qualifier above. */
if (!useless_type_conversion_p (TREE_TYPE (expr), TREE_TYPE (*expr_p)))
*expr_p = fold_convert (TREE_TYPE (expr), *expr_p);
}
/* *EXPR_P is a NOP_EXPR or CONVERT_EXPR. Remove it and/or other conversions
underneath as appropriate. */
static enum gimplify_status
gimplify_conversion (tree *expr_p)
{
location_t loc = EXPR_LOCATION (*expr_p);
gcc_assert (CONVERT_EXPR_P (*expr_p));
/* Then strip away all but the outermost conversion. */
STRIP_SIGN_NOPS (TREE_OPERAND (*expr_p, 0));
/* And remove the outermost conversion if it's useless. */
if (tree_ssa_useless_type_conversion (*expr_p))
*expr_p = TREE_OPERAND (*expr_p, 0);
/* If we still have a conversion at the toplevel,
then canonicalize some constructs. */
if (CONVERT_EXPR_P (*expr_p))
{
tree sub = TREE_OPERAND (*expr_p, 0);
/* If a NOP conversion is changing the type of a COMPONENT_REF
expression, then canonicalize its type now in order to expose more
redundant conversions. */
if (TREE_CODE (sub) == COMPONENT_REF)
canonicalize_component_ref (&TREE_OPERAND (*expr_p, 0));
/* If a NOP conversion is changing a pointer to array of foo
to a pointer to foo, embed that change in the ADDR_EXPR. */
else if (TREE_CODE (sub) == ADDR_EXPR)
canonicalize_addr_expr (expr_p);
}
/* If we have a conversion to a non-register type force the
use of a VIEW_CONVERT_EXPR instead. */
if (CONVERT_EXPR_P (*expr_p) && !is_gimple_reg_type (TREE_TYPE (*expr_p)))
*expr_p = fold_build1_loc (loc, VIEW_CONVERT_EXPR, TREE_TYPE (*expr_p),
TREE_OPERAND (*expr_p, 0));
return GS_OK;
}
/* Nonlocal VLAs seen in the current function. */
static struct pointer_set_t *nonlocal_vlas;
/* The VAR_DECLs created for nonlocal VLAs for debug info purposes. */
static tree nonlocal_vla_vars;
/* Gimplify a VAR_DECL or PARM_DECL. Return GS_OK if we expanded a
DECL_VALUE_EXPR, and it's worth re-examining things. */
static enum gimplify_status
gimplify_var_or_parm_decl (tree *expr_p)
{
tree decl = *expr_p;
/* ??? If this is a local variable, and it has not been seen in any
outer BIND_EXPR, then it's probably the result of a duplicate
declaration, for which we've already issued an error. It would
be really nice if the front end wouldn't leak these at all.
Currently the only known culprit is C++ destructors, as seen
in g++.old-deja/g++.jason/binding.C. */
if (TREE_CODE (decl) == VAR_DECL
&& !DECL_SEEN_IN_BIND_EXPR_P (decl)
&& !TREE_STATIC (decl) && !DECL_EXTERNAL (decl)
&& decl_function_context (decl) == current_function_decl)
{
gcc_assert (seen_error ());
return GS_ERROR;
}
/* When within an OpenMP context, notice uses of variables. */
if (gimplify_omp_ctxp && omp_notice_variable (gimplify_omp_ctxp, decl, true))
return GS_ALL_DONE;
/* If the decl is an alias for another expression, substitute it now. */
if (DECL_HAS_VALUE_EXPR_P (decl))
{
tree value_expr = DECL_VALUE_EXPR (decl);
/* For referenced nonlocal VLAs add a decl for debugging purposes
to the current function. */
if (TREE_CODE (decl) == VAR_DECL
&& TREE_CODE (DECL_SIZE_UNIT (decl)) != INTEGER_CST
&& nonlocal_vlas != NULL
&& TREE_CODE (value_expr) == INDIRECT_REF
&& TREE_CODE (TREE_OPERAND (value_expr, 0)) == VAR_DECL
&& decl_function_context (decl) != current_function_decl)
{
struct gimplify_omp_ctx *ctx = gimplify_omp_ctxp;
while (ctx && ctx->region_type == ORT_WORKSHARE)
ctx = ctx->outer_context;
if (!ctx && !pointer_set_insert (nonlocal_vlas, decl))
{
tree copy = copy_node (decl);
lang_hooks.dup_lang_specific_decl (copy);
SET_DECL_RTL (copy, 0);
TREE_USED (copy) = 1;
DECL_CHAIN (copy) = nonlocal_vla_vars;
nonlocal_vla_vars = copy;
SET_DECL_VALUE_EXPR (copy, unshare_expr (value_expr));
DECL_HAS_VALUE_EXPR_P (copy) = 1;
}
}
*expr_p = unshare_expr (value_expr);
return GS_OK;
}
return GS_ALL_DONE;
}
/* Gimplify the COMPONENT_REF, ARRAY_REF, REALPART_EXPR or IMAGPART_EXPR
node *EXPR_P.
compound_lval
: min_lval '[' val ']'
| min_lval '.' ID
| compound_lval '[' val ']'
| compound_lval '.' ID
This is not part of the original SIMPLE definition, which separates
array and member references, but it seems reasonable to handle them
together. Also, this way we don't run into problems with union
aliasing; gcc requires that for accesses through a union to alias, the
union reference must be explicit, which was not always the case when we
were splitting up array and member refs.
PRE_P points to the sequence where side effects that must happen before
*EXPR_P should be stored.
POST_P points to the sequence where side effects that must happen after
*EXPR_P should be stored. */
static enum gimplify_status
gimplify_compound_lval (tree *expr_p, gimple_seq *pre_p, gimple_seq *post_p,
fallback_t fallback)
{
tree *p;
vec<tree> expr_stack;
enum gimplify_status ret = GS_ALL_DONE, tret;
int i;
location_t loc = EXPR_LOCATION (*expr_p);
tree expr = *expr_p;
/* Create a stack of the subexpressions so later we can walk them in
order from inner to outer. */
expr_stack.create (10);
/* We can handle anything that get_inner_reference can deal with. */
for (p = expr_p; ; p = &TREE_OPERAND (*p, 0))
{
restart:
/* Fold INDIRECT_REFs now to turn them into ARRAY_REFs. */
if (TREE_CODE (*p) == INDIRECT_REF)
*p = fold_indirect_ref_loc (loc, *p);
if (handled_component_p (*p))
;
/* Expand DECL_VALUE_EXPR now. In some cases that may expose
additional COMPONENT_REFs. */
else if ((TREE_CODE (*p) == VAR_DECL || TREE_CODE (*p) == PARM_DECL)
&& gimplify_var_or_parm_decl (p) == GS_OK)
goto restart;
else
break;
expr_stack.safe_push (*p);
}
gcc_assert (expr_stack.length ());
/* Now EXPR_STACK is a stack of pointers to all the refs we've
walked through and P points to the innermost expression.
Java requires that we elaborated nodes in source order. That
means we must gimplify the inner expression followed by each of
the indices, in order. But we can't gimplify the inner
expression until we deal with any variable bounds, sizes, or
positions in order to deal with PLACEHOLDER_EXPRs.
So we do this in three steps. First we deal with the annotations
for any variables in the components, then we gimplify the base,
then we gimplify any indices, from left to right. */
for (i = expr_stack.length () - 1; i >= 0; i--)
{
tree t = expr_stack[i];
if (TREE_CODE (t) == ARRAY_REF || TREE_CODE (t) == ARRAY_RANGE_REF)
{
/* Gimplify the low bound and element type size and put them into
the ARRAY_REF. If these values are set, they have already been
gimplified. */
if (TREE_OPERAND (t, 2) == NULL_TREE)
{
tree low = unshare_expr (array_ref_low_bound (t));
if (!is_gimple_min_invariant (low))
{
TREE_OPERAND (t, 2) = low;
tret = gimplify_expr (&TREE_OPERAND (t, 2), pre_p,
post_p, is_gimple_reg,
fb_rvalue);
ret = MIN (ret, tret);
}
}
else
{
tret = gimplify_expr (&TREE_OPERAND (t, 2), pre_p, post_p,
is_gimple_reg, fb_rvalue);
ret = MIN (ret, tret);
}
if (TREE_OPERAND (t, 3) == NULL_TREE)
{
tree elmt_type = TREE_TYPE (TREE_TYPE (TREE_OPERAND (t, 0)));
tree elmt_size = unshare_expr (array_ref_element_size (t));
tree factor = size_int (TYPE_ALIGN_UNIT (elmt_type));
/* Divide the element size by the alignment of the element
type (above). */
elmt_size
= size_binop_loc (loc, EXACT_DIV_EXPR, elmt_size, factor);
if (!is_gimple_min_invariant (elmt_size))
{
TREE_OPERAND (t, 3) = elmt_size;
tret = gimplify_expr (&TREE_OPERAND (t, 3), pre_p,
post_p, is_gimple_reg,
fb_rvalue);
ret = MIN (ret, tret);
}
}
else
{
tret = gimplify_expr (&TREE_OPERAND (t, 3), pre_p, post_p,
is_gimple_reg, fb_rvalue);
ret = MIN (ret, tret);
}
}
else if (TREE_CODE (t) == COMPONENT_REF)
{
/* Set the field offset into T and gimplify it. */
if (TREE_OPERAND (t, 2) == NULL_TREE)
{
tree offset = unshare_expr (component_ref_field_offset (t));
tree field = TREE_OPERAND (t, 1);
tree factor
= size_int (DECL_OFFSET_ALIGN (field) / BITS_PER_UNIT);
/* Divide the offset by its alignment. */
offset = size_binop_loc (loc, EXACT_DIV_EXPR, offset, factor);
if (!is_gimple_min_invariant (offset))
{
TREE_OPERAND (t, 2) = offset;
tret = gimplify_expr (&TREE_OPERAND (t, 2), pre_p,
post_p, is_gimple_reg,
fb_rvalue);
ret = MIN (ret, tret);
}
}
else
{
tret = gimplify_expr (&TREE_OPERAND (t, 2), pre_p, post_p,
is_gimple_reg, fb_rvalue);
ret = MIN (ret, tret);
}
}
}
/* Step 2 is to gimplify the base expression. Make sure lvalue is set
so as to match the min_lval predicate. Failure to do so may result
in the creation of large aggregate temporaries. */
tret = gimplify_expr (p, pre_p, post_p, is_gimple_min_lval,
fallback | fb_lvalue);
ret = MIN (ret, tret);
/* And finally, the indices and operands of ARRAY_REF. During this
loop we also remove any useless conversions. */
for (; expr_stack.length () > 0; )
{
tree t = expr_stack.pop ();
if (TREE_CODE (t) == ARRAY_REF || TREE_CODE (t) == ARRAY_RANGE_REF)
{
/* Gimplify the dimension. */
if (!is_gimple_min_invariant (TREE_OPERAND (t, 1)))
{
tret = gimplify_expr (&TREE_OPERAND (t, 1), pre_p, post_p,
is_gimple_val, fb_rvalue);
ret = MIN (ret, tret);
}
}
STRIP_USELESS_TYPE_CONVERSION (TREE_OPERAND (t, 0));
/* The innermost expression P may have originally had
TREE_SIDE_EFFECTS set which would have caused all the outer
expressions in *EXPR_P leading to P to also have had
TREE_SIDE_EFFECTS set. */
recalculate_side_effects (t);
}
/* If the outermost expression is a COMPONENT_REF, canonicalize its type. */
if ((fallback & fb_rvalue) && TREE_CODE (*expr_p) == COMPONENT_REF)
{
canonicalize_component_ref (expr_p);
}
expr_stack.release ();
gcc_assert (*expr_p == expr || ret != GS_ALL_DONE);
return ret;
}
/* Gimplify the self modifying expression pointed to by EXPR_P
(++, --, +=, -=).
PRE_P points to the list where side effects that must happen before
*EXPR_P should be stored.
POST_P points to the list where side effects that must happen after
*EXPR_P should be stored.
WANT_VALUE is nonzero iff we want to use the value of this expression
in another expression.
ARITH_TYPE is the type the computation should be performed in. */
enum gimplify_status
gimplify_self_mod_expr (tree *expr_p, gimple_seq *pre_p, gimple_seq *post_p,
bool want_value, tree arith_type)
{
enum tree_code code;
tree lhs, lvalue, rhs, t1;
gimple_seq post = NULL, *orig_post_p = post_p;
bool postfix;
enum tree_code arith_code;
enum gimplify_status ret;
location_t loc = EXPR_LOCATION (*expr_p);
code = TREE_CODE (*expr_p);
gcc_assert (code == POSTINCREMENT_EXPR || code == POSTDECREMENT_EXPR
|| code == PREINCREMENT_EXPR || code == PREDECREMENT_EXPR);
/* Prefix or postfix? */
if (code == POSTINCREMENT_EXPR || code == POSTDECREMENT_EXPR)
/* Faster to treat as prefix if result is not used. */
postfix = want_value;
else
postfix = false;
/* For postfix, make sure the inner expression's post side effects
are executed after side effects from this expression. */
if (postfix)
post_p = &post;
/* Add or subtract? */
if (code == PREINCREMENT_EXPR || code == POSTINCREMENT_EXPR)
arith_code = PLUS_EXPR;
else
arith_code = MINUS_EXPR;
/* Gimplify the LHS into a GIMPLE lvalue. */
lvalue = TREE_OPERAND (*expr_p, 0);
ret = gimplify_expr (&lvalue, pre_p, post_p, is_gimple_lvalue, fb_lvalue);
if (ret == GS_ERROR)
return ret;
/* Extract the operands to the arithmetic operation. */
lhs = lvalue;
rhs = TREE_OPERAND (*expr_p, 1);
/* For postfix operator, we evaluate the LHS to an rvalue and then use
that as the result value and in the postqueue operation. */
if (postfix)
{
ret = gimplify_expr (&lhs, pre_p, post_p, is_gimple_val, fb_rvalue);
if (ret == GS_ERROR)
return ret;
lhs = get_initialized_tmp_var (lhs, pre_p, NULL);
}
/* For POINTERs increment, use POINTER_PLUS_EXPR. */
if (POINTER_TYPE_P (TREE_TYPE (lhs)))
{
rhs = convert_to_ptrofftype_loc (loc, rhs);
if (arith_code == MINUS_EXPR)
rhs = fold_build1_loc (loc, NEGATE_EXPR, TREE_TYPE (rhs), rhs);
t1 = fold_build2 (POINTER_PLUS_EXPR, TREE_TYPE (*expr_p), lhs, rhs);
}
else
t1 = fold_convert (TREE_TYPE (*expr_p),
fold_build2 (arith_code, arith_type,
fold_convert (arith_type, lhs),
fold_convert (arith_type, rhs)));
if (postfix)
{
gimplify_assign (lvalue, t1, pre_p);
gimplify_seq_add_seq (orig_post_p, post);
*expr_p = lhs;
return GS_ALL_DONE;
}
else
{
*expr_p = build2 (MODIFY_EXPR, TREE_TYPE (lvalue), lvalue, t1);
return GS_OK;
}
}
/* If *EXPR_P has a variable sized type, wrap it in a WITH_SIZE_EXPR. */
static void
maybe_with_size_expr (tree *expr_p)
{
tree expr = *expr_p;
tree type = TREE_TYPE (expr);
tree size;
/* If we've already wrapped this or the type is error_mark_node, we can't do
anything. */
if (TREE_CODE (expr) == WITH_SIZE_EXPR
|| type == error_mark_node)
return;
/* If the size isn't known or is a constant, we have nothing to do. */
size = TYPE_SIZE_UNIT (type);
if (!size || TREE_CODE (size) == INTEGER_CST)
return;
/* Otherwise, make a WITH_SIZE_EXPR. */
size = unshare_expr (size);
size = SUBSTITUTE_PLACEHOLDER_IN_EXPR (size, expr);
*expr_p = build2 (WITH_SIZE_EXPR, type, expr, size);
}
/* Helper for gimplify_call_expr. Gimplify a single argument *ARG_P
Store any side-effects in PRE_P. CALL_LOCATION is the location of
the CALL_EXPR. */
static enum gimplify_status
gimplify_arg (tree *arg_p, gimple_seq *pre_p, location_t call_location)
{
bool (*test) (tree);
fallback_t fb;
/* In general, we allow lvalues for function arguments to avoid
extra overhead of copying large aggregates out of even larger
aggregates into temporaries only to copy the temporaries to
the argument list. Make optimizers happy by pulling out to
temporaries those types that fit in registers. */
if (is_gimple_reg_type (TREE_TYPE (*arg_p)))
test = is_gimple_val, fb = fb_rvalue;
else
{
test = is_gimple_lvalue, fb = fb_either;
/* Also strip a TARGET_EXPR that would force an extra copy. */
if (TREE_CODE (*arg_p) == TARGET_EXPR)
{
tree init = TARGET_EXPR_INITIAL (*arg_p);
if (init
&& !VOID_TYPE_P (TREE_TYPE (init)))
*arg_p = init;
}
}
/* If this is a variable sized type, we must remember the size. */
maybe_with_size_expr (arg_p);
/* FIXME diagnostics: This will mess up gcc.dg/Warray-bounds.c. */
/* Make sure arguments have the same location as the function call
itself. */
protected_set_expr_location (*arg_p, call_location);
/* There is a sequence point before a function call. Side effects in
the argument list must occur before the actual call. So, when
gimplifying arguments, force gimplify_expr to use an internal
post queue which is then appended to the end of PRE_P. */
return gimplify_expr (arg_p, pre_p, NULL, test, fb);
}
/* Gimplify the CALL_EXPR node *EXPR_P into the GIMPLE sequence PRE_P.
WANT_VALUE is true if the result of the call is desired. */
static enum gimplify_status
gimplify_call_expr (tree *expr_p, gimple_seq *pre_p, bool want_value)
{
tree fndecl, parms, p, fnptrtype;
enum gimplify_status ret;
int i, nargs;
gimple call;
bool builtin_va_start_p = FALSE;
location_t loc = EXPR_LOCATION (*expr_p);
gcc_assert (TREE_CODE (*expr_p) == CALL_EXPR);
/* For reliable diagnostics during inlining, it is necessary that
every call_expr be annotated with file and line. */
if (! EXPR_HAS_LOCATION (*expr_p))
SET_EXPR_LOCATION (*expr_p, input_location);
/* This may be a call to a builtin function.
Builtin function calls may be transformed into different
(and more efficient) builtin function calls under certain
circumstances. Unfortunately, gimplification can muck things
up enough that the builtin expanders are not aware that certain
transformations are still valid.
So we attempt transformation/gimplification of the call before
we gimplify the CALL_EXPR. At this time we do not manage to
transform all calls in the same manner as the expanders do, but
we do transform most of them. */
fndecl = get_callee_fndecl (*expr_p);
if (fndecl
&& DECL_BUILT_IN_CLASS (fndecl) == BUILT_IN_NORMAL)
switch (DECL_FUNCTION_CODE (fndecl))
{
case BUILT_IN_VA_START:
{
builtin_va_start_p = TRUE;
if (call_expr_nargs (*expr_p) < 2)
{
error ("too few arguments to function %<va_start%>");
*expr_p = build_empty_stmt (EXPR_LOCATION (*expr_p));
return GS_OK;
}
if (fold_builtin_next_arg (*expr_p, true))
{
*expr_p = build_empty_stmt (EXPR_LOCATION (*expr_p));
return GS_OK;
}
break;
}
case BUILT_IN_LINE:
{
expanded_location loc = expand_location (EXPR_LOCATION (*expr_p));
*expr_p = build_int_cst (TREE_TYPE (*expr_p), loc.line);
return GS_OK;
}
case BUILT_IN_FILE:
{
expanded_location loc = expand_location (EXPR_LOCATION (*expr_p));
*expr_p = build_string_literal (strlen (loc.file) + 1, loc.file);
return GS_OK;
}
case BUILT_IN_FUNCTION:
{
const char *function;
function = IDENTIFIER_POINTER (DECL_NAME (current_function_decl));
*expr_p = build_string_literal (strlen (function) + 1, function);
return GS_OK;
}
default:
;
}
if (fndecl && DECL_BUILT_IN (fndecl))
{
tree new_tree = fold_call_expr (input_location, *expr_p, !want_value);
if (new_tree && new_tree != *expr_p)
{
/* There was a transformation of this call which computes the
same value, but in a more efficient way. Return and try
again. */
*expr_p = new_tree;
return GS_OK;
}
}
/* Remember the original function pointer type. */
fnptrtype = TREE_TYPE (CALL_EXPR_FN (*expr_p));
/* There is a sequence point before the call, so any side effects in
the calling expression must occur before the actual call. Force
gimplify_expr to use an internal post queue. */
ret = gimplify_expr (&CALL_EXPR_FN (*expr_p), pre_p, NULL,
is_gimple_call_addr, fb_rvalue);
nargs = call_expr_nargs (*expr_p);
/* Get argument types for verification. */
fndecl = get_callee_fndecl (*expr_p);
parms = NULL_TREE;
if (fndecl)
parms = TYPE_ARG_TYPES (TREE_TYPE (fndecl));
else if (POINTER_TYPE_P (TREE_TYPE (CALL_EXPR_FN (*expr_p))))
parms = TYPE_ARG_TYPES (TREE_TYPE (TREE_TYPE (CALL_EXPR_FN (*expr_p))));
if (fndecl && DECL_ARGUMENTS (fndecl))
p = DECL_ARGUMENTS (fndecl);
else if (parms)
p = parms;
else
p = NULL_TREE;
for (i = 0; i < nargs && p; i++, p = TREE_CHAIN (p))
;
/* If the last argument is __builtin_va_arg_pack () and it is not
passed as a named argument, decrease the number of CALL_EXPR
arguments and set instead the CALL_EXPR_VA_ARG_PACK flag. */
if (!p
&& i < nargs
&& TREE_CODE (CALL_EXPR_ARG (*expr_p, nargs - 1)) == CALL_EXPR)
{
tree last_arg = CALL_EXPR_ARG (*expr_p, nargs - 1);
tree last_arg_fndecl = get_callee_fndecl (last_arg);
if (last_arg_fndecl
&& TREE_CODE (last_arg_fndecl) == FUNCTION_DECL
&& DECL_BUILT_IN_CLASS (last_arg_fndecl) == BUILT_IN_NORMAL
&& DECL_FUNCTION_CODE (last_arg_fndecl) == BUILT_IN_VA_ARG_PACK)
{
tree call = *expr_p;
--nargs;
*expr_p = build_call_array_loc (loc, TREE_TYPE (call),
CALL_EXPR_FN (call),
nargs, CALL_EXPR_ARGP (call));
/* Copy all CALL_EXPR flags, location and block, except
CALL_EXPR_VA_ARG_PACK flag. */
CALL_EXPR_STATIC_CHAIN (*expr_p) = CALL_EXPR_STATIC_CHAIN (call);
CALL_EXPR_TAILCALL (*expr_p) = CALL_EXPR_TAILCALL (call);
CALL_EXPR_RETURN_SLOT_OPT (*expr_p)
= CALL_EXPR_RETURN_SLOT_OPT (call);
CALL_FROM_THUNK_P (*expr_p) = CALL_FROM_THUNK_P (call);
SET_EXPR_LOCATION (*expr_p, EXPR_LOCATION (call));
/* Set CALL_EXPR_VA_ARG_PACK. */
CALL_EXPR_VA_ARG_PACK (*expr_p) = 1;
}
}
/* Finally, gimplify the function arguments. */
if (nargs > 0)
{
for (i = (PUSH_ARGS_REVERSED ? nargs - 1 : 0);
PUSH_ARGS_REVERSED ? i >= 0 : i < nargs;
PUSH_ARGS_REVERSED ? i-- : i++)
{
enum gimplify_status t;
/* Avoid gimplifying the second argument to va_start, which needs to
be the plain PARM_DECL. */
if ((i != 1) || !builtin_va_start_p)
{
t = gimplify_arg (&CALL_EXPR_ARG (*expr_p, i), pre_p,
EXPR_LOCATION (*expr_p));
if (t == GS_ERROR)
ret = GS_ERROR;
}
}
}
/* Verify the function result. */
if (want_value && fndecl
&& VOID_TYPE_P (TREE_TYPE (TREE_TYPE (fnptrtype))))
{
error_at (loc, "using result of function returning %<void%>");
ret = GS_ERROR;
}
/* Try this again in case gimplification exposed something. */
if (ret != GS_ERROR)
{
tree new_tree = fold_call_expr (input_location, *expr_p, !want_value);
if (new_tree && new_tree != *expr_p)
{
/* There was a transformation of this call which computes the
same value, but in a more efficient way. Return and try
again. */
*expr_p = new_tree;
return GS_OK;
}
}
else
{
*expr_p = error_mark_node;
return GS_ERROR;
}
/* If the function is "const" or "pure", then clear TREE_SIDE_EFFECTS on its
decl. This allows us to eliminate redundant or useless
calls to "const" functions. */
if (TREE_CODE (*expr_p) == CALL_EXPR)
{
int flags = call_expr_flags (*expr_p);
if (flags & (ECF_CONST | ECF_PURE)
/* An infinite loop is considered a side effect. */
&& !(flags & (ECF_LOOPING_CONST_OR_PURE)))
TREE_SIDE_EFFECTS (*expr_p) = 0;
}
/* If the value is not needed by the caller, emit a new GIMPLE_CALL
and clear *EXPR_P. Otherwise, leave *EXPR_P in its gimplified
form and delegate the creation of a GIMPLE_CALL to
gimplify_modify_expr. This is always possible because when
WANT_VALUE is true, the caller wants the result of this call into
a temporary, which means that we will emit an INIT_EXPR in
internal_get_tmp_var which will then be handled by
gimplify_modify_expr. */
if (!want_value)
{
/* The CALL_EXPR in *EXPR_P is already in GIMPLE form, so all we
have to do is replicate it as a GIMPLE_CALL tuple. */
gimple_stmt_iterator gsi;
call = gimple_build_call_from_tree (*expr_p);
gimple_call_set_fntype (call, TREE_TYPE (fnptrtype));
gimplify_seq_add_stmt (pre_p, call);
gsi = gsi_last (*pre_p);
fold_stmt (&gsi);
*expr_p = NULL_TREE;
}
else
/* Remember the original function type. */
CALL_EXPR_FN (*expr_p) = build1 (NOP_EXPR, fnptrtype,
CALL_EXPR_FN (*expr_p));
return ret;
}
/* Handle shortcut semantics in the predicate operand of a COND_EXPR by
rewriting it into multiple COND_EXPRs, and possibly GOTO_EXPRs.
TRUE_LABEL_P and FALSE_LABEL_P point to the labels to jump to if the
condition is true or false, respectively. If null, we should generate
our own to skip over the evaluation of this specific expression.
LOCUS is the source location of the COND_EXPR.
This function is the tree equivalent of do_jump.
shortcut_cond_r should only be called by shortcut_cond_expr. */
static tree
shortcut_cond_r (tree pred, tree *true_label_p, tree *false_label_p,
location_t locus)
{
tree local_label = NULL_TREE;
tree t, expr = NULL;
/* OK, it's not a simple case; we need to pull apart the COND_EXPR to
retain the shortcut semantics. Just insert the gotos here;
shortcut_cond_expr will append the real blocks later. */
if (TREE_CODE (pred) == TRUTH_ANDIF_EXPR)
{
location_t new_locus;
/* Turn if (a && b) into
if (a); else goto no;
if (b) goto yes; else goto no;
(no:) */
if (false_label_p == NULL)
false_label_p = &local_label;
/* Keep the original source location on the first 'if'. */
t = shortcut_cond_r (TREE_OPERAND (pred, 0), NULL, false_label_p, locus);
append_to_statement_list (t, &expr);
/* Set the source location of the && on the second 'if'. */
new_locus = EXPR_HAS_LOCATION (pred) ? EXPR_LOCATION (pred) : locus;
t = shortcut_cond_r (TREE_OPERAND (pred, 1), true_label_p, false_label_p,
new_locus);
append_to_statement_list (t, &expr);
}
else if (TREE_CODE (pred) == TRUTH_ORIF_EXPR)
{
location_t new_locus;
/* Turn if (a || b) into
if (a) goto yes;
if (b) goto yes; else goto no;
(yes:) */
if (true_label_p == NULL)
true_label_p = &local_label;
/* Keep the original source location on the first 'if'. */
t = shortcut_cond_r (TREE_OPERAND (pred, 0), true_label_p, NULL, locus);
append_to_statement_list (t, &expr);
/* Set the source location of the || on the second 'if'. */
new_locus = EXPR_HAS_LOCATION (pred) ? EXPR_LOCATION (pred) : locus;
t = shortcut_cond_r (TREE_OPERAND (pred, 1), true_label_p, false_label_p,
new_locus);
append_to_statement_list (t, &expr);
}
else if (TREE_CODE (pred) == COND_EXPR
&& !VOID_TYPE_P (TREE_TYPE (TREE_OPERAND (pred, 1)))
&& !VOID_TYPE_P (TREE_TYPE (TREE_OPERAND (pred, 2))))
{
location_t new_locus;
/* As long as we're messing with gotos, turn if (a ? b : c) into
if (a)
if (b) goto yes; else goto no;
else
if (c) goto yes; else goto no;
Don't do this if one of the arms has void type, which can happen
in C++ when the arm is throw. */
/* Keep the original source location on the first 'if'. Set the source
location of the ? on the second 'if'. */
new_locus = EXPR_HAS_LOCATION (pred) ? EXPR_LOCATION (pred) : locus;
expr = build3 (COND_EXPR, void_type_node, TREE_OPERAND (pred, 0),
shortcut_cond_r (TREE_OPERAND (pred, 1), true_label_p,
false_label_p, locus),
shortcut_cond_r (TREE_OPERAND (pred, 2), true_label_p,
false_label_p, new_locus));
}
else
{
expr = build3 (COND_EXPR, void_type_node, pred,
build_and_jump (true_label_p),
build_and_jump (false_label_p));
SET_EXPR_LOCATION (expr, locus);
}
if (local_label)
{
t = build1 (LABEL_EXPR, void_type_node, local_label);
append_to_statement_list (t, &expr);
}
return expr;
}
/* Given a conditional expression EXPR with short-circuit boolean
predicates using TRUTH_ANDIF_EXPR or TRUTH_ORIF_EXPR, break the
predicate apart into the equivalent sequence of conditionals. */
static tree
shortcut_cond_expr (tree expr)
{
tree pred = TREE_OPERAND (expr, 0);
tree then_ = TREE_OPERAND (expr, 1);
tree else_ = TREE_OPERAND (expr, 2);
tree true_label, false_label, end_label, t;
tree *true_label_p;
tree *false_label_p;
bool emit_end, emit_false, jump_over_else;
bool then_se = then_ && TREE_SIDE_EFFECTS (then_);
bool else_se = else_ && TREE_SIDE_EFFECTS (else_);
/* First do simple transformations. */
if (!else_se)
{
/* If there is no 'else', turn
if (a && b) then c
into
if (a) if (b) then c. */
while (TREE_CODE (pred) == TRUTH_ANDIF_EXPR)
{
/* Keep the original source location on the first 'if'. */
location_t locus = EXPR_LOC_OR_HERE (expr);
TREE_OPERAND (expr, 0) = TREE_OPERAND (pred, 1);
/* Set the source location of the && on the second 'if'. */
if (EXPR_HAS_LOCATION (pred))
SET_EXPR_LOCATION (expr, EXPR_LOCATION (pred));
then_ = shortcut_cond_expr (expr);
then_se = then_ && TREE_SIDE_EFFECTS (then_);
pred = TREE_OPERAND (pred, 0);
expr = build3 (COND_EXPR, void_type_node, pred, then_, NULL_TREE);
SET_EXPR_LOCATION (expr, locus);
}
}
if (!then_se)
{
/* If there is no 'then', turn
if (a || b); else d
into
if (a); else if (b); else d. */
while (TREE_CODE (pred) == TRUTH_ORIF_EXPR)
{
/* Keep the original source location on the first 'if'. */
location_t locus = EXPR_LOC_OR_HERE (expr);
TREE_OPERAND (expr, 0) = TREE_OPERAND (pred, 1);
/* Set the source location of the || on the second 'if'. */
if (EXPR_HAS_LOCATION (pred))
SET_EXPR_LOCATION (expr, EXPR_LOCATION (pred));
else_ = shortcut_cond_expr (expr);
else_se = else_ && TREE_SIDE_EFFECTS (else_);
pred = TREE_OPERAND (pred, 0);
expr = build3 (COND_EXPR, void_type_node, pred, NULL_TREE, else_);
SET_EXPR_LOCATION (expr, locus);
}
}
/* If we're done, great. */
if (TREE_CODE (pred) != TRUTH_ANDIF_EXPR
&& TREE_CODE (pred) != TRUTH_ORIF_EXPR)
return expr;
/* Otherwise we need to mess with gotos. Change
if (a) c; else d;
to
if (a); else goto no;
c; goto end;
no: d; end:
and recursively gimplify the condition. */
true_label = false_label = end_label = NULL_TREE;
/* If our arms just jump somewhere, hijack those labels so we don't
generate jumps to jumps. */
if (then_
&& TREE_CODE (then_) == GOTO_EXPR
&& TREE_CODE (GOTO_DESTINATION (then_)) == LABEL_DECL)
{
true_label = GOTO_DESTINATION (then_);
then_ = NULL;
then_se = false;
}
if (else_
&& TREE_CODE (else_) == GOTO_EXPR
&& TREE_CODE (GOTO_DESTINATION (else_)) == LABEL_DECL)
{
false_label = GOTO_DESTINATION (else_);
else_ = NULL;
else_se = false;
}
/* If we aren't hijacking a label for the 'then' branch, it falls through. */
if (true_label)
true_label_p = &true_label;
else
true_label_p = NULL;
/* The 'else' branch also needs a label if it contains interesting code. */
if (false_label || else_se)
false_label_p = &false_label;
else
false_label_p = NULL;
/* If there was nothing else in our arms, just forward the label(s). */
if (!then_se && !else_se)
return shortcut_cond_r (pred, true_label_p, false_label_p,
EXPR_LOC_OR_HERE (expr));
/* If our last subexpression already has a terminal label, reuse it. */
if (else_se)
t = expr_last (else_);
else if (then_se)
t = expr_last (then_);
else
t = NULL;
if (t && TREE_CODE (t) == LABEL_EXPR)
end_label = LABEL_EXPR_LABEL (t);
/* If we don't care about jumping to the 'else' branch, jump to the end
if the condition is false. */
if (!false_label_p)
false_label_p = &end_label;
/* We only want to emit these labels if we aren't hijacking them. */
emit_end = (end_label == NULL_TREE);
emit_false = (false_label == NULL_TREE);
/* We only emit the jump over the else clause if we have to--if the
then clause may fall through. Otherwise we can wind up with a
useless jump and a useless label at the end of gimplified code,
which will cause us to think that this conditional as a whole
falls through even if it doesn't. If we then inline a function
which ends with such a condition, that can cause us to issue an
inappropriate warning about control reaching the end of a
non-void function. */
jump_over_else = block_may_fallthru (then_);
pred = shortcut_cond_r (pred, true_label_p, false_label_p,
EXPR_LOC_OR_HERE (expr));
expr = NULL;
append_to_statement_list (pred, &expr);
append_to_statement_list (then_, &expr);
if (else_se)
{
if (jump_over_else)
{
tree last = expr_last (expr);
t = build_and_jump (&end_label);
if (EXPR_HAS_LOCATION (last))
SET_EXPR_LOCATION (t, EXPR_LOCATION (last));
append_to_statement_list (t, &expr);
}
if (emit_false)
{
t = build1 (LABEL_EXPR, void_type_node, false_label);
append_to_statement_list (t, &expr);
}
append_to_statement_list (else_, &expr);
}
if (emit_end && end_label)
{
t = build1 (LABEL_EXPR, void_type_node, end_label);
append_to_statement_list (t, &expr);
}
return expr;
}
/* EXPR is used in a boolean context; make sure it has BOOLEAN_TYPE. */
tree
gimple_boolify (tree expr)
{
tree type = TREE_TYPE (expr);
location_t loc = EXPR_LOCATION (expr);
if (TREE_CODE (expr) == NE_EXPR
&& TREE_CODE (TREE_OPERAND (expr, 0)) == CALL_EXPR
&& integer_zerop (TREE_OPERAND (expr, 1)))
{
tree call = TREE_OPERAND (expr, 0);
tree fn = get_callee_fndecl (call);
/* For __builtin_expect ((long) (x), y) recurse into x as well
if x is truth_value_p. */
if (fn
&& DECL_BUILT_IN_CLASS (fn) == BUILT_IN_NORMAL
&& DECL_FUNCTION_CODE (fn) == BUILT_IN_EXPECT
&& call_expr_nargs (call) == 2)
{
tree arg = CALL_EXPR_ARG (call, 0);
if (arg)
{
if (TREE_CODE (arg) == NOP_EXPR
&& TREE_TYPE (arg) == TREE_TYPE (call))
arg = TREE_OPERAND (arg, 0);
if (truth_value_p (TREE_CODE (arg)))
{
arg = gimple_boolify (arg);
CALL_EXPR_ARG (call, 0)
= fold_convert_loc (loc, TREE_TYPE (call), arg);
}
}
}
}
switch (TREE_CODE (expr))
{
case TRUTH_AND_EXPR:
case TRUTH_OR_EXPR:
case TRUTH_XOR_EXPR:
case TRUTH_ANDIF_EXPR:
case TRUTH_ORIF_EXPR:
/* Also boolify the arguments of truth exprs. */
TREE_OPERAND (expr, 1) = gimple_boolify (TREE_OPERAND (expr, 1));
/* FALLTHRU */
case TRUTH_NOT_EXPR:
TREE_OPERAND (expr, 0) = gimple_boolify (TREE_OPERAND (expr, 0));
/* These expressions always produce boolean results. */
if (TREE_CODE (type) != BOOLEAN_TYPE)
TREE_TYPE (expr) = boolean_type_node;
return expr;
default:
if (COMPARISON_CLASS_P (expr))
{
/* There expressions always prduce boolean results. */
if (TREE_CODE (type) != BOOLEAN_TYPE)
TREE_TYPE (expr) = boolean_type_node;
return expr;
}
/* Other expressions that get here must have boolean values, but
might need to be converted to the appropriate mode. */
if (TREE_CODE (type) == BOOLEAN_TYPE)
return expr;
return fold_convert_loc (loc, boolean_type_node, expr);
}
}
/* Given a conditional expression *EXPR_P without side effects, gimplify
its operands. New statements are inserted to PRE_P. */
static enum gimplify_status
gimplify_pure_cond_expr (tree *expr_p, gimple_seq *pre_p)
{
tree expr = *expr_p, cond;
enum gimplify_status ret, tret;
enum tree_code code;
cond = gimple_boolify (COND_EXPR_COND (expr));
/* We need to handle && and || specially, as their gimplification
creates pure cond_expr, thus leading to an infinite cycle otherwise. */
code = TREE_CODE (cond);
if (code == TRUTH_ANDIF_EXPR)
TREE_SET_CODE (cond, TRUTH_AND_EXPR);
else if (code == TRUTH_ORIF_EXPR)
TREE_SET_CODE (cond, TRUTH_OR_EXPR);
ret = gimplify_expr (&cond, pre_p, NULL, is_gimple_condexpr, fb_rvalue);
COND_EXPR_COND (*expr_p) = cond;
tret = gimplify_expr (&COND_EXPR_THEN (expr), pre_p, NULL,
is_gimple_val, fb_rvalue);
ret = MIN (ret, tret);
tret = gimplify_expr (&COND_EXPR_ELSE (expr), pre_p, NULL,
is_gimple_val, fb_rvalue);
return MIN (ret, tret);
}
/* Return true if evaluating EXPR could trap.
EXPR is GENERIC, while tree_could_trap_p can be called
only on GIMPLE. */
static bool
generic_expr_could_trap_p (tree expr)
{
unsigned i, n;
if (!expr || is_gimple_val (expr))
return false;
if (!EXPR_P (expr) || tree_could_trap_p (expr))
return true;
n = TREE_OPERAND_LENGTH (expr);
for (i = 0; i < n; i++)
if (generic_expr_could_trap_p (TREE_OPERAND (expr, i)))
return true;
return false;
}
/* Convert the conditional expression pointed to by EXPR_P '(p) ? a : b;'
into
if (p) if (p)
t1 = a; a;
else or else
t1 = b; b;
t1;
The second form is used when *EXPR_P is of type void.
PRE_P points to the list where side effects that must happen before
*EXPR_P should be stored. */
static enum gimplify_status
gimplify_cond_expr (tree *expr_p, gimple_seq *pre_p, fallback_t fallback)
{
tree expr = *expr_p;
tree type = TREE_TYPE (expr);
location_t loc = EXPR_LOCATION (expr);
tree tmp, arm1, arm2;
enum gimplify_status ret;
tree label_true, label_false, label_cont;
bool have_then_clause_p, have_else_clause_p;
gimple gimple_cond;
enum tree_code pred_code;
gimple_seq seq = NULL;
/* If this COND_EXPR has a value, copy the values into a temporary within
the arms. */
if (!VOID_TYPE_P (type))
{
tree then_ = TREE_OPERAND (expr, 1), else_ = TREE_OPERAND (expr, 2);
tree result;
/* If either an rvalue is ok or we do not require an lvalue, create the
temporary. But we cannot do that if the type is addressable. */
if (((fallback & fb_rvalue) || !(fallback & fb_lvalue))
&& !TREE_ADDRESSABLE (type))
{
if (gimplify_ctxp->allow_rhs_cond_expr
/* If either branch has side effects or could trap, it can't be
evaluated unconditionally. */
&& !TREE_SIDE_EFFECTS (then_)
&& !generic_expr_could_trap_p (then_)
&& !TREE_SIDE_EFFECTS (else_)
&& !generic_expr_could_trap_p (else_))
return gimplify_pure_cond_expr (expr_p, pre_p);
tmp = create_tmp_var (type, "iftmp");
result = tmp;
}
/* Otherwise, only create and copy references to the values. */
else
{
type = build_pointer_type (type);
if (!VOID_TYPE_P (TREE_TYPE (then_)))
then_ = build_fold_addr_expr_loc (loc, then_);
if (!VOID_TYPE_P (TREE_TYPE (else_)))
else_ = build_fold_addr_expr_loc (loc, else_);
expr
= build3 (COND_EXPR, type, TREE_OPERAND (expr, 0), then_, else_);
tmp = create_tmp_var (type, "iftmp");
result = build_simple_mem_ref_loc (loc, tmp);
}
/* Build the new then clause, `tmp = then_;'. But don't build the
assignment if the value is void; in C++ it can be if it's a throw. */
if (!VOID_TYPE_P (TREE_TYPE (then_)))
TREE_OPERAND (expr, 1) = build2 (MODIFY_EXPR, type, tmp, then_);
/* Similarly, build the new else clause, `tmp = else_;'. */
if (!VOID_TYPE_P (TREE_TYPE (else_)))
TREE_OPERAND (expr, 2) = build2 (MODIFY_EXPR, type, tmp, else_);
TREE_TYPE (expr) = void_type_node;
recalculate_side_effects (expr);
/* Move the COND_EXPR to the prequeue. */
gimplify_stmt (&expr, pre_p);
*expr_p = result;
return GS_ALL_DONE;
}
/* Remove any COMPOUND_EXPR so the following cases will be caught. */
STRIP_TYPE_NOPS (TREE_OPERAND (expr, 0));
if (TREE_CODE (TREE_OPERAND (expr, 0)) == COMPOUND_EXPR)
gimplify_compound_expr (&TREE_OPERAND (expr, 0), pre_p, true);
/* Make sure the condition has BOOLEAN_TYPE. */
TREE_OPERAND (expr, 0) = gimple_boolify (TREE_OPERAND (expr, 0));
/* Break apart && and || conditions. */
if (TREE_CODE (TREE_OPERAND (expr, 0)) == TRUTH_ANDIF_EXPR
|| TREE_CODE (TREE_OPERAND (expr, 0)) == TRUTH_ORIF_EXPR)
{
expr = shortcut_cond_expr (expr);
if (expr != *expr_p)
{
*expr_p = expr;
/* We can't rely on gimplify_expr to re-gimplify the expanded
form properly, as cleanups might cause the target labels to be
wrapped in a TRY_FINALLY_EXPR. To prevent that, we need to
set up a conditional context. */
gimple_push_condition ();
gimplify_stmt (expr_p, &seq);
gimple_pop_condition (pre_p);
gimple_seq_add_seq (pre_p, seq);
return