/* Scalar Replacement of Aggregates (SRA) converts some structure
references into scalar references, exposing them to the scalar
optimizers.
- Copyright (C) 2008, 2009 Free Software Foundation, Inc.
+ Copyright (C) 2008, 2009, 2010 Free Software Foundation, Inc.
Contributed by Martin Jambor <mjambor@suse.cz>
This file is part of GCC.
#include "tm.h"
#include "tree.h"
#include "gimple.h"
+#include "cgraph.h"
#include "tree-flow.h"
#include "ipa-prop.h"
-#include "diagnostic.h"
+#include "tree-pretty-print.h"
#include "statistics.h"
#include "tree-dump.h"
#include "timevar.h"
#include "params.h"
#include "target.h"
#include "flags.h"
+#include "dbgcnt.h"
+#include "tree-inline.h"
/* Enumeration of all aggregate reductions we can do. */
-enum sra_mode { SRA_MODE_EARLY_INTRA, /* early intraprocedural SRA */
- SRA_MODE_INTRA }; /* late intraprocedural SRA */
+enum sra_mode { SRA_MODE_EARLY_IPA, /* early call regularization */
+ SRA_MODE_EARLY_INTRA, /* early intraprocedural SRA */
+ SRA_MODE_INTRA }; /* late intraprocedural SRA */
/* Global variable describing which aggregate reduction we are performing at
the moment. */
HOST_WIDE_INT size;
tree base;
- /* Expression. */
+ /* Expression. It is context dependent so do not use it to create new
+ expressions to access the original aggregate. See PR 42154 for a
+ testcase. */
tree expr;
/* Type. */
tree type;
+ /* The statement this access belongs to. */
+ gimple stmt;
+
/* Next group representative for this aggregate. */
struct access *next_grp;
points to the first one. */
struct access *first_child;
- /* Pointer to the next sibling in the access tree as described above. */
+ /* In intraprocedural SRA, pointer to the next sibling in the access tree as
+ described above. In IPA-SRA this is a pointer to the next access
+ belonging to the same group (having the same representative). */
struct access *next_sibling;
/* Pointers to the first and last element in the linked list of assign
/* Is this particular access write access? */
unsigned write : 1;
+ /* Is this access an artificial one created to scalarize some record
+ entirely? */
+ unsigned total_scalarization : 1;
+
/* Is this access currently in the work queue? */
unsigned grp_queued : 1;
+
/* Does this group contain a write access? This flag is propagated down the
access tree. */
unsigned grp_write : 1;
+
/* Does this group contain a read access? This flag is propagated down the
access tree. */
unsigned grp_read : 1;
+
+ /* Does this group contain a read access that comes from an assignment
+ statement? This flag is propagated down the access tree. */
+ unsigned grp_assignment_read : 1;
+
/* Other passes of the analysis use this bit to make function
analyze_access_subtree create scalar replacements for this group if
possible. */
unsigned grp_hint : 1;
+
/* Is the subtree rooted in this access fully covered by scalar
replacements? */
unsigned grp_covered : 1;
+
/* If set to true, this access and all below it in an access tree must not be
scalarized. */
unsigned grp_unscalarizable_region : 1;
+
/* Whether data have been written to parts of the aggregate covered by this
access which is not to be scalarized. This flag is propagated up in the
access tree. */
unsigned grp_unscalarized_data : 1;
+
/* Does this access and/or group contain a write access through a
BIT_FIELD_REF? */
unsigned grp_partial_lhs : 1;
the decision and creation at different places because create_tmp_var
cannot be called from within FOR_EACH_REFERENCED_VAR. */
unsigned grp_to_be_replaced : 1;
+
+ /* Is it possible that the group refers to data which might be (directly or
+ otherwise) modified? */
+ unsigned grp_maybe_modified : 1;
+
+ /* Set when this is a representative of a pointer to scalar (i.e. by
+ reference) parameter which we consider for turning into a plain scalar
+ (i.e. a by value parameter). */
+ unsigned grp_scalar_ptr : 1;
+
+ /* Set when we discover that this pointer is not safe to dereference in the
+ caller. */
+ unsigned grp_not_necessarilly_dereferenced : 1;
};
typedef struct access *access_p;
/* Base (tree) -> Vector (VEC(access_p,heap) *) map. */
static struct pointer_map_t *base_access_vec;
-/* Bitmap of bases (candidates). */
+/* Bitmap of candidates. */
static bitmap candidate_bitmap;
+
+/* Bitmap of candidates which we should try to entirely scalarize away and
+ those which cannot be (because they are and need be used as a whole). */
+static bitmap should_scalarize_away_bitmap, cannot_scalarize_away_bitmap;
+
/* Obstack for creation of fancy names. */
static struct obstack name_obstack;
propagated to their assignment counterparts. */
static struct access *work_queue_head;
+/* Number of parameters of the analyzed function when doing early ipa SRA. */
+static int func_param_count;
+
+/* scan_function sets the following to true if it encounters a call to
+ __builtin_apply_args. */
+static bool encountered_apply_args;
+
+/* Set by scan_function when it finds a recursive call. */
+static bool encountered_recursive_call;
+
+/* Set by scan_function when it finds a recursive call with less actual
+ arguments than formal parameters.. */
+static bool encountered_unchangable_recursive_call;
+
+/* This is a table in which for each basic block and parameter there is a
+ distance (offset + size) in that parameter which is dereferenced and
+ accessed in that BB. */
+static HOST_WIDE_INT *bb_dereferences;
+/* Bitmap of BBs that can cause the function to "stop" progressing by
+ returning, throwing externally, looping infinitely or calling a function
+ which might abort etc.. */
+static bitmap final_bbs;
+
+/* Representative of no accesses at all. */
+static struct access no_accesses_representant;
+
+/* Predicate to test the special value. */
+
+static inline bool
+no_accesses_p (struct access *access)
+{
+ return access == &no_accesses_representant;
+}
+
/* Dump contents of ACCESS to file F in a human friendly way. If GRP is true,
representative fields are dumped, otherwise those which only describe the
individual access are. */
static struct
{
+ /* Number of processed aggregates is readily available in
+ analyze_all_variable_accesses and so is not stored here. */
+
/* Number of created scalar replacements. */
int replacements;
references. */
int separate_lhs_rhs_handling;
- /* Number of processed aggregates is readily available in
- analyze_all_variable_accesses and so is not stored here. */
+ /* Number of parameters that were removed because they were unused. */
+ int deleted_unused_parameters;
+
+ /* Number of scalars passed as parameters by reference that have been
+ converted to be passed by value. */
+ int scalar_by_ref_to_by_val;
+
+ /* Number of aggregate parameters that were replaced by one or more of their
+ components. */
+ int aggregate_params_reduced;
+
+ /* Numbber of components created when splitting aggregate parameters. */
+ int param_reductions_created;
} sra_stats;
static void
fprintf (f, ", type = ");
print_generic_expr (f, access->type, 0);
if (grp)
- fprintf (f, ", grp_write = %d, grp_read = %d, grp_hint = %d, "
+ fprintf (f, ", grp_write = %d, total_scalarization = %d, "
+ "grp_read = %d, grp_hint = %d, grp_assignment_read = %d,"
"grp_covered = %d, grp_unscalarizable_region = %d, "
"grp_unscalarized_data = %d, grp_partial_lhs = %d, "
- "grp_to_be_replaced = %d\n",
- access->grp_write, access->grp_read, access->grp_hint,
+ "grp_to_be_replaced = %d, grp_maybe_modified = %d, "
+ "grp_not_necessarilly_dereferenced = %d\n",
+ access->grp_write, access->total_scalarization,
+ access->grp_read, access->grp_hint, access->grp_assignment_read,
access->grp_covered, access->grp_unscalarizable_region,
access->grp_unscalarized_data, access->grp_partial_lhs,
- access->grp_to_be_replaced);
+ access->grp_to_be_replaced, access->grp_maybe_modified,
+ access->grp_not_necessarilly_dereferenced);
else
- fprintf (f, ", write = %d, grp_partial_lhs = %d\n", access->write,
+ fprintf (f, ", write = %d, total_scalarization = %d, "
+ "grp_partial_lhs = %d\n",
+ access->write, access->total_scalarization,
access->grp_partial_lhs);
}
sra_initialize (void)
{
candidate_bitmap = BITMAP_ALLOC (NULL);
+ should_scalarize_away_bitmap = BITMAP_ALLOC (NULL);
+ cannot_scalarize_away_bitmap = BITMAP_ALLOC (NULL);
gcc_obstack_init (&name_obstack);
access_pool = create_alloc_pool ("SRA accesses", sizeof (struct access), 16);
link_pool = create_alloc_pool ("SRA links", sizeof (struct assign_link), 16);
base_access_vec = pointer_map_create ();
memset (&sra_stats, 0, sizeof (sra_stats));
+ encountered_apply_args = false;
+ encountered_recursive_call = false;
+ encountered_unchangable_recursive_call = false;
}
/* Hook fed to pointer_map_traverse, deallocate stored vectors. */
sra_deinitialize (void)
{
BITMAP_FREE (candidate_bitmap);
+ BITMAP_FREE (should_scalarize_away_bitmap);
+ BITMAP_FREE (cannot_scalarize_away_bitmap);
free_alloc_pool (access_pool);
free_alloc_pool (link_pool);
obstack_free (&name_obstack, NULL);
}
}
+/* If T is an SSA_NAME, return NULL if it is not a default def or return its
+ base variable if it is. Return T if it is not an SSA_NAME. */
+
+static tree
+get_ssa_base_param (tree t)
+{
+ if (TREE_CODE (t) == SSA_NAME)
+ {
+ if (SSA_NAME_IS_DEFAULT_DEF (t))
+ return SSA_NAME_VAR (t);
+ else
+ return NULL_TREE;
+ }
+ return t;
+}
+
+/* Mark a dereference of BASE of distance DIST in a basic block tht STMT
+ belongs to, unless the BB has already been marked as a potentially
+ final. */
+
+static void
+mark_parm_dereference (tree base, HOST_WIDE_INT dist, gimple stmt)
+{
+ basic_block bb = gimple_bb (stmt);
+ int idx, parm_index = 0;
+ tree parm;
+
+ if (bitmap_bit_p (final_bbs, bb->index))
+ return;
+
+ for (parm = DECL_ARGUMENTS (current_function_decl);
+ parm && parm != base;
+ parm = TREE_CHAIN (parm))
+ parm_index++;
+
+ gcc_assert (parm_index < func_param_count);
+
+ idx = bb->index * func_param_count + parm_index;
+ if (bb_dereferences[idx] < dist)
+ bb_dereferences[idx] = dist;
+}
+
+/* Allocate an access structure for BASE, OFFSET and SIZE, clear it, fill in
+ the three fields. Also add it to the vector of accesses corresponding to
+ the base. Finally, return the new access. */
+
+static struct access *
+create_access_1 (tree base, HOST_WIDE_INT offset, HOST_WIDE_INT size)
+{
+ VEC (access_p, heap) *vec;
+ struct access *access;
+ void **slot;
+
+ access = (struct access *) pool_alloc (access_pool);
+ memset (access, 0, sizeof (struct access));
+ access->base = base;
+ access->offset = offset;
+ access->size = size;
+
+ slot = pointer_map_contains (base_access_vec, base);
+ if (slot)
+ vec = (VEC (access_p, heap) *) *slot;
+ else
+ vec = VEC_alloc (access_p, heap, 32);
+
+ VEC_safe_push (access_p, heap, vec, access);
+
+ *((struct VEC (access_p,heap) **)
+ pointer_map_insert (base_access_vec, base)) = vec;
+
+ return access;
+}
+
/* Create and insert access for EXPR. Return created access, or NULL if it is
not possible. */
static struct access *
-create_access (tree expr, bool write)
+create_access (tree expr, gimple stmt, bool write)
{
struct access *access;
- void **slot;
- VEC (access_p,heap) *vec;
HOST_WIDE_INT offset, size, max_size;
tree base = expr;
- bool unscalarizable_region = false;
+ bool ptr, unscalarizable_region = false;
base = get_ref_base_and_extent (expr, &offset, &size, &max_size);
+ if (sra_mode == SRA_MODE_EARLY_IPA && INDIRECT_REF_P (base))
+ {
+ base = get_ssa_base_param (TREE_OPERAND (base, 0));
+ if (!base)
+ return NULL;
+ ptr = true;
+ }
+ else
+ ptr = false;
+
if (!DECL_P (base) || !bitmap_bit_p (candidate_bitmap, DECL_UID (base)))
return NULL;
- if (size != max_size)
+ if (sra_mode == SRA_MODE_EARLY_IPA)
{
- size = max_size;
- unscalarizable_region = true;
- }
+ if (size < 0 || size != max_size)
+ {
+ disqualify_candidate (base, "Encountered a variable sized access.");
+ return NULL;
+ }
+ if ((offset % BITS_PER_UNIT) != 0 || (size % BITS_PER_UNIT) != 0)
+ {
+ disqualify_candidate (base,
+ "Encountered an acces not aligned to a byte.");
+ return NULL;
+ }
- if (size < 0)
+ if (ptr)
+ mark_parm_dereference (base, offset + size, stmt);
+ }
+ else
{
- disqualify_candidate (base, "Encountered an unconstrained access.");
- return NULL;
+ if (size != max_size)
+ {
+ size = max_size;
+ unscalarizable_region = true;
+ }
+ if (size < 0)
+ {
+ disqualify_candidate (base, "Encountered an unconstrained access.");
+ return NULL;
+ }
}
- access = (struct access *) pool_alloc (access_pool);
- memset (access, 0, sizeof (struct access));
-
- access->base = base;
- access->offset = offset;
- access->size = size;
+ access = create_access_1 (base, offset, size);
access->expr = expr;
access->type = TREE_TYPE (expr);
access->write = write;
access->grp_unscalarizable_region = unscalarizable_region;
+ access->stmt = stmt;
- slot = pointer_map_contains (base_access_vec, base);
- if (slot)
- vec = (VEC (access_p, heap) *) *slot;
- else
- vec = VEC_alloc (access_p, heap, 32);
+ return access;
+}
- VEC_safe_push (access_p, heap, vec, access);
- *((struct VEC (access_p,heap) **)
- pointer_map_insert (base_access_vec, base)) = vec;
+/* Return true iff TYPE is a RECORD_TYPE with fields that are either of gimple
+ register types or (recursively) records with only these two kinds of fields.
+ It also returns false if any of these records has a zero-size field as its
+ last field. */
- return access;
+static bool
+type_consists_of_records_p (tree type)
+{
+ tree fld;
+ bool last_fld_has_zero_size = false;
+
+ if (TREE_CODE (type) != RECORD_TYPE)
+ return false;
+
+ for (fld = TYPE_FIELDS (type); fld; fld = TREE_CHAIN (fld))
+ if (TREE_CODE (fld) == FIELD_DECL)
+ {
+ tree ft = TREE_TYPE (fld);
+
+ if (!is_gimple_reg_type (ft)
+ && !type_consists_of_records_p (ft))
+ return false;
+
+ last_fld_has_zero_size = tree_low_cst (DECL_SIZE (fld), 1) == 0;
+ }
+
+ if (last_fld_has_zero_size)
+ return false;
+
+ return true;
+}
+
+/* Create total_scalarization accesses for all scalar type fields in DECL that
+ must be of a RECORD_TYPE conforming to type_consists_of_records_p. BASE
+ must be the top-most VAR_DECL representing the variable, OFFSET must be the
+ offset of DECL within BASE. */
+
+static void
+completely_scalarize_record (tree base, tree decl, HOST_WIDE_INT offset)
+{
+ tree fld, decl_type = TREE_TYPE (decl);
+
+ for (fld = TYPE_FIELDS (decl_type); fld; fld = TREE_CHAIN (fld))
+ if (TREE_CODE (fld) == FIELD_DECL)
+ {
+ HOST_WIDE_INT pos = offset + int_bit_position (fld);
+ tree ft = TREE_TYPE (fld);
+
+ if (is_gimple_reg_type (ft))
+ {
+ struct access *access;
+ HOST_WIDE_INT size;
+ tree expr;
+ bool ok;
+
+ size = tree_low_cst (DECL_SIZE (fld), 1);
+ expr = base;
+ ok = build_ref_for_offset (&expr, TREE_TYPE (base), pos,
+ ft, false);
+ gcc_assert (ok);
+
+ access = create_access_1 (base, pos, size);
+ access->expr = expr;
+ access->type = ft;
+ access->total_scalarization = 1;
+ /* Accesses for intraprocedural SRA can have their stmt NULL. */
+ }
+ else
+ completely_scalarize_record (base, fld, pos);
+ }
}
while (handled_component_p (t))
t = TREE_OPERAND (t, 0);
- if (DECL_P (t))
+ if (sra_mode == SRA_MODE_EARLY_IPA)
+ {
+ if (INDIRECT_REF_P (t))
+ t = TREE_OPERAND (t, 0);
+ t = get_ssa_base_param (t);
+ }
+
+ if (t && DECL_P (t))
disqualify_candidate (t, reason);
}
created. */
static struct access *
-build_access_from_expr_1 (tree *expr_ptr, bool write)
+build_access_from_expr_1 (tree expr, gimple stmt, bool write)
{
struct access *ret = NULL;
- tree expr = *expr_ptr;
bool partial_ref;
if (TREE_CODE (expr) == BIT_FIELD_REF
switch (TREE_CODE (expr))
{
+ case INDIRECT_REF:
+ if (sra_mode != SRA_MODE_EARLY_IPA)
+ return NULL;
+ /* fall through */
case VAR_DECL:
case PARM_DECL:
case RESULT_DECL:
case COMPONENT_REF:
case ARRAY_REF:
case ARRAY_RANGE_REF:
- ret = create_access (expr, write);
+ ret = create_access (expr, stmt, write);
break;
default:
return ret;
}
-/* Callback of scan_function. Scan expression EXPR and create access
- structures for all accesses to candidates for scalarization. Return true if
- any access has been inserted. */
+/* Scan expression EXPR and create access structures for all accesses to
+ candidates for scalarization. Return true if any access has been inserted.
+ STMT must be the statement from which the expression is taken, WRITE must be
+ true if the expression is a store and false otherwise. */
static bool
-build_access_from_expr (tree *expr_ptr,
- gimple_stmt_iterator *gsi ATTRIBUTE_UNUSED, bool write,
- void *data ATTRIBUTE_UNUSED)
+build_access_from_expr (tree expr, gimple stmt, bool write)
{
- return build_access_from_expr_1 (expr_ptr, write) != NULL;
+ struct access *access;
+
+ access = build_access_from_expr_1 (expr, stmt, write);
+ if (access)
+ {
+ /* This means the aggregate is accesses as a whole in a way other than an
+ assign statement and thus cannot be removed even if we had a scalar
+ replacement for everything. */
+ if (cannot_scalarize_away_bitmap)
+ bitmap_set_bit (cannot_scalarize_away_bitmap, DECL_UID (access->base));
+ return true;
+ }
+ return false;
}
/* Disqualify LHS and RHS for scalarization if STMT must end its basic block in
static bool
disqualify_ops_if_throwing_stmt (gimple stmt, tree lhs, tree rhs)
{
- if (stmt_can_throw_internal (stmt) || stmt_ends_bb_p (stmt))
+ if ((sra_mode == SRA_MODE_EARLY_INTRA || sra_mode == SRA_MODE_INTRA)
+ && (stmt_can_throw_internal (stmt) || stmt_ends_bb_p (stmt)))
{
disqualify_base_of_expr (lhs, "LHS of a throwing stmt.");
if (rhs)
return false;
}
-
-/* Result code for scan_assign callback for scan_function. */
-enum scan_assign_result { SRA_SA_NONE, /* nothing done for the stmt */
- SRA_SA_PROCESSED, /* stmt analyzed/changed */
- SRA_SA_REMOVED }; /* stmt redundant and eliminated */
-
-
-/* Callback of scan_function. Scan expressions occuring in the statement
- pointed to by STMT_EXPR, create access structures for all accesses to
- candidates for scalarization and remove those candidates which occur in
+/* Scan expressions occuring in STMT, create access structures for all accesses
+ to candidates for scalarization and remove those candidates which occur in
statements or expressions that prevent them from being split apart. Return
true if any access has been inserted. */
-static enum scan_assign_result
-build_accesses_from_assign (gimple *stmt_ptr,
- gimple_stmt_iterator *gsi ATTRIBUTE_UNUSED,
- void *data ATTRIBUTE_UNUSED)
+static bool
+build_accesses_from_assign (gimple stmt)
{
- gimple stmt = *stmt_ptr;
- tree *lhs_ptr, *rhs_ptr;
+ tree lhs, rhs;
struct access *lacc, *racc;
if (!gimple_assign_single_p (stmt))
- return SRA_SA_NONE;
+ return false;
- lhs_ptr = gimple_assign_lhs_ptr (stmt);
- rhs_ptr = gimple_assign_rhs1_ptr (stmt);
+ lhs = gimple_assign_lhs (stmt);
+ rhs = gimple_assign_rhs1 (stmt);
- if (disqualify_ops_if_throwing_stmt (stmt, *lhs_ptr, *rhs_ptr))
- return SRA_SA_NONE;
+ if (disqualify_ops_if_throwing_stmt (stmt, lhs, rhs))
+ return false;
+
+ racc = build_access_from_expr_1 (rhs, stmt, false);
+ lacc = build_access_from_expr_1 (lhs, stmt, true);
- racc = build_access_from_expr_1 (rhs_ptr, false);
- lacc = build_access_from_expr_1 (lhs_ptr, true);
+ if (racc)
+ {
+ racc->grp_assignment_read = 1;
+ if (should_scalarize_away_bitmap && !gimple_has_volatile_ops (stmt)
+ && !is_gimple_reg_type (racc->type))
+ bitmap_set_bit (should_scalarize_away_bitmap, DECL_UID (racc->base));
+ }
if (lacc && racc
+ && (sra_mode == SRA_MODE_EARLY_INTRA || sra_mode == SRA_MODE_INTRA)
&& !lacc->grp_unscalarizable_region
&& !racc->grp_unscalarizable_region
- && AGGREGATE_TYPE_P (TREE_TYPE (*lhs_ptr))
+ && AGGREGATE_TYPE_P (TREE_TYPE (lhs))
/* FIXME: Turn the following line into an assert after PR 40058 is
fixed. */
&& lacc->size == racc->size
add_link_to_rhs (racc, link);
}
- return (lacc || racc) ? SRA_SA_PROCESSED : SRA_SA_NONE;
+ return lacc || racc;
}
/* Callback of walk_stmt_load_store_addr_ops visit_addr used to determine
asm_visit_addr (gimple stmt ATTRIBUTE_UNUSED, tree op,
void *data ATTRIBUTE_UNUSED)
{
- if (DECL_P (op))
+ op = get_base_address (op);
+ if (op
+ && DECL_P (op))
disqualify_candidate (op, "Non-scalarizable GIMPLE_ASM operand.");
return false;
}
+/* Return true iff callsite CALL has at least as many actual arguments as there
+ are formal parameters of the function currently processed by IPA-SRA. */
+
+static inline bool
+callsite_has_enough_arguments_p (gimple call)
+{
+ return gimple_call_num_args (call) >= (unsigned) func_param_count;
+}
-/* Scan function and look for interesting statements. Return true if any has
- been found or processed, as indicated by callbacks. SCAN_EXPR is a callback
- called on all expressions within statements except assign statements and
- those deemed entirely unsuitable for some reason (all operands in such
- statements and expression are removed from candidate_bitmap). SCAN_ASSIGN
- is a callback called on all assign statements, HANDLE_SSA_DEFS is a callback
- called on assign statements and those call statements which have a lhs and
- it is the only callback which can be NULL. ANALYSIS_STAGE is true when
- running in the analysis stage of a pass and thus no statement is being
- modified. DATA is a pointer passed to all callbacks. If any single
- callback returns true, this function also returns true, otherwise it returns
- false. */
+/* Scan function and look for interesting expressions and create access
+ structures for them. Return true iff any access is created. */
static bool
-scan_function (bool (*scan_expr) (tree *, gimple_stmt_iterator *, bool, void *),
- enum scan_assign_result (*scan_assign) (gimple *,
- gimple_stmt_iterator *,
- void *),
- bool (*handle_ssa_defs)(gimple, void *),
- bool analysis_stage, void *data)
+scan_function (void)
{
- gimple_stmt_iterator gsi;
basic_block bb;
- unsigned i;
- tree *t;
bool ret = false;
FOR_EACH_BB (bb)
{
- bool bb_changed = false;
-
- gsi = gsi_start_bb (bb);
- while (!gsi_end_p (gsi))
+ gimple_stmt_iterator gsi;
+ for (gsi = gsi_start_bb (bb); !gsi_end_p (gsi); gsi_next (&gsi))
{
gimple stmt = gsi_stmt (gsi);
- enum scan_assign_result assign_result;
- bool any = false, deleted = false;
+ tree t;
+ unsigned i;
+ if (final_bbs && stmt_can_throw_external (stmt))
+ bitmap_set_bit (final_bbs, bb->index);
switch (gimple_code (stmt))
{
case GIMPLE_RETURN:
- t = gimple_return_retval_ptr (stmt);
- if (*t != NULL_TREE)
- any |= scan_expr (t, &gsi, false, data);
+ t = gimple_return_retval (stmt);
+ if (t != NULL_TREE)
+ ret |= build_access_from_expr (t, stmt, false);
+ if (final_bbs)
+ bitmap_set_bit (final_bbs, bb->index);
break;
case GIMPLE_ASSIGN:
- assign_result = scan_assign (&stmt, &gsi, data);
- any |= assign_result == SRA_SA_PROCESSED;
- deleted = assign_result == SRA_SA_REMOVED;
- if (handle_ssa_defs && assign_result != SRA_SA_REMOVED)
- any |= handle_ssa_defs (stmt, data);
+ ret |= build_accesses_from_assign (stmt);
break;
case GIMPLE_CALL:
- /* Operands must be processed before the lhs. */
for (i = 0; i < gimple_call_num_args (stmt); i++)
- {
- tree *argp = gimple_call_arg_ptr (stmt, i);
- any |= scan_expr (argp, &gsi, false, data);
- }
+ ret |= build_access_from_expr (gimple_call_arg (stmt, i),
+ stmt, false);
- if (gimple_call_lhs (stmt))
+ if (sra_mode == SRA_MODE_EARLY_IPA)
{
- tree *lhs_ptr = gimple_call_lhs_ptr (stmt);
- if (!analysis_stage
- || !disqualify_ops_if_throwing_stmt (stmt,
- *lhs_ptr, NULL))
+ tree dest = gimple_call_fndecl (stmt);
+ int flags = gimple_call_flags (stmt);
+
+ if (dest)
{
- any |= scan_expr (lhs_ptr, &gsi, true, data);
- if (handle_ssa_defs)
- any |= handle_ssa_defs (stmt, data);
+ if (DECL_BUILT_IN_CLASS (dest) == BUILT_IN_NORMAL
+ && DECL_FUNCTION_CODE (dest) == BUILT_IN_APPLY_ARGS)
+ encountered_apply_args = true;
+ if (cgraph_get_node (dest)
+ == cgraph_get_node (current_function_decl))
+ {
+ encountered_recursive_call = true;
+ if (!callsite_has_enough_arguments_p (stmt))
+ encountered_unchangable_recursive_call = true;
+ }
}
+
+ if (final_bbs
+ && (flags & (ECF_CONST | ECF_PURE)) == 0)
+ bitmap_set_bit (final_bbs, bb->index);
}
+
+ t = gimple_call_lhs (stmt);
+ if (t && !disqualify_ops_if_throwing_stmt (stmt, t, NULL))
+ ret |= build_access_from_expr (t, stmt, true);
break;
case GIMPLE_ASM:
+ walk_stmt_load_store_addr_ops (stmt, NULL, NULL, NULL,
+ asm_visit_addr);
+ if (final_bbs)
+ bitmap_set_bit (final_bbs, bb->index);
- if (analysis_stage)
- walk_stmt_load_store_addr_ops (stmt, NULL, NULL, NULL,
- asm_visit_addr);
for (i = 0; i < gimple_asm_ninputs (stmt); i++)
{
- tree *op = &TREE_VALUE (gimple_asm_input_op (stmt, i));
- any |= scan_expr (op, &gsi, false, data);
+ t = TREE_VALUE (gimple_asm_input_op (stmt, i));
+ ret |= build_access_from_expr (t, stmt, false);
}
for (i = 0; i < gimple_asm_noutputs (stmt); i++)
{
- tree *op = &TREE_VALUE (gimple_asm_output_op (stmt, i));
- any |= scan_expr (op, &gsi, true, data);
+ t = TREE_VALUE (gimple_asm_output_op (stmt, i));
+ ret |= build_access_from_expr (t, stmt, true);
}
+ break;
default:
break;
}
-
- if (any)
- {
- ret = true;
- bb_changed = true;
-
- if (!analysis_stage)
- {
- update_stmt (stmt);
- if (!stmt_could_throw_p (stmt))
- remove_stmt_from_eh_region (stmt);
- }
- }
- if (deleted)
- bb_changed = true;
- else
- {
- gsi_next (&gsi);
- ret = true;
- }
}
- if (!analysis_stage && bb_changed)
- gimple_purge_dead_eh_edges (bb);
}
return ret;
if (f1->size == f2->size)
{
+ if (f1->type == f2->type)
+ return 0;
/* Put any non-aggregate type before any aggregate type. */
- if (!is_gimple_reg_type (f1->type)
- && is_gimple_reg_type (f2->type))
+ else if (!is_gimple_reg_type (f1->type)
+ && is_gimple_reg_type (f2->type))
return 1;
else if (is_gimple_reg_type (f1->type)
&& !is_gimple_reg_type (f2->type))
return -1;
+ /* Put any complex or vector type before any other scalar type. */
+ else if (TREE_CODE (f1->type) != COMPLEX_TYPE
+ && TREE_CODE (f1->type) != VECTOR_TYPE
+ && (TREE_CODE (f2->type) == COMPLEX_TYPE
+ || TREE_CODE (f2->type) == VECTOR_TYPE))
+ return 1;
+ else if ((TREE_CODE (f1->type) == COMPLEX_TYPE
+ || TREE_CODE (f1->type) == VECTOR_TYPE)
+ && TREE_CODE (f2->type) != COMPLEX_TYPE
+ && TREE_CODE (f2->type) != VECTOR_TYPE)
+ return -1;
/* Put the integral type with the bigger precision first. */
else if (INTEGRAL_TYPE_P (f1->type)
- && INTEGRAL_TYPE_P (f2->type))
- return TYPE_PRECISION (f1->type) > TYPE_PRECISION (f2->type) ? -1 : 1;
+ && INTEGRAL_TYPE_P (f2->type))
+ return TYPE_PRECISION (f2->type) - TYPE_PRECISION (f1->type);
/* Put any integral type with non-full precision last. */
else if (INTEGRAL_TYPE_P (f1->type)
&& (TREE_INT_CST_LOW (TYPE_SIZE (f1->type))
case UNION_TYPE:
case QUAL_UNION_TYPE:
case RECORD_TYPE:
- /* Some ADA records are half-unions, treat all of them the same. */
for (fld = TYPE_FIELDS (type); fld; fld = TREE_CHAIN (fld))
{
HOST_WIDE_INT pos, size;
pos = int_bit_position (fld);
gcc_assert (TREE_CODE (type) == RECORD_TYPE || pos == 0);
- size = tree_low_cst (DECL_SIZE (fld), 1);
- if (pos > offset || (pos + size) <= offset)
+ tr_size = DECL_SIZE (fld);
+ if (!tr_size || !host_integerp (tr_size, 1))
+ continue;
+ size = tree_low_cst (tr_size, 1);
+ if (size == 0)
+ {
+ if (pos != offset)
+ continue;
+ }
+ else if (pos > offset || (pos + size) <= offset)
continue;
if (res)
el_size = tree_low_cst (tr_size, 1);
minidx = TYPE_MIN_VALUE (TYPE_DOMAIN (type));
- if (TREE_CODE (minidx) != INTEGER_CST)
+ if (TREE_CODE (minidx) != INTEGER_CST || el_size == 0)
return false;
if (res)
{
/* Construct an expression that would reference a part of aggregate *EXPR of
type TYPE at the given OFFSET of the type EXP_TYPE. If EXPR is NULL, the
function only determines whether it can build such a reference without
- actually doing it.
+ actually doing it, otherwise, the tree it points to is unshared first and
+ then used as a base for furhter sub-references.
FIXME: Eventually this should be replaced with
maybe_fold_offset_to_reference() from tree-ssa-ccp.c but that requires a
{
location_t loc = expr ? EXPR_LOCATION (*expr) : UNKNOWN_LOCATION;
+ if (expr)
+ *expr = unshare_expr (*expr);
+
if (allow_ptr && POINTER_TYPE_P (type))
{
type = TREE_TYPE (type);
return build_ref_for_offset_1 (expr, type, offset, exp_type);
}
+/* Return true iff TYPE is stdarg va_list type. */
+
+static inline bool
+is_va_list_type (tree type)
+{
+ return TYPE_MAIN_VARIANT (type) == TYPE_MAIN_VARIANT (va_list_type_node);
+}
+
/* The very first phase of intraprocedural SRA. It marks in candidate_bitmap
those with type which is suitable for scalarization. */
|| !COMPLETE_TYPE_P (type)
|| !host_integerp (TYPE_SIZE (type), 1)
|| tree_low_cst (TYPE_SIZE (type), 1) == 0
- || type_internals_preclude_sra_p (type))
+ || type_internals_preclude_sra_p (type)
+ /* Fix for PR 41089. tree-stdarg.c needs to have va_lists intact but
+ we also want to schedule it rather late. Thus we ignore it in
+ the early pass. */
+ || (sra_mode == SRA_MODE_EARLY_INTRA
+ && is_va_list_type (type)))
continue;
bitmap_set_bit (candidate_bitmap, DECL_UID (var));
struct access *access = VEC_index (access_p, access_vec, i);
bool grp_write = access->write;
bool grp_read = !access->write;
+ bool grp_assignment_read = access->grp_assignment_read;
bool multiple_reads = false;
+ bool total_scalarization = access->total_scalarization;
bool grp_partial_lhs = access->grp_partial_lhs;
bool first_scalar = is_gimple_reg_type (access->type);
bool unscalarizable_region = access->grp_unscalarizable_region;
else
grp_read = true;
}
+ grp_assignment_read |= ac2->grp_assignment_read;
grp_partial_lhs |= ac2->grp_partial_lhs;
unscalarizable_region |= ac2->grp_unscalarizable_region;
+ total_scalarization |= ac2->total_scalarization;
relink_to_new_repr (access, ac2);
/* If there are both aggregate-type and scalar-type accesses with
access->group_representative = access;
access->grp_write = grp_write;
access->grp_read = grp_read;
- access->grp_hint = multiple_reads;
+ access->grp_assignment_read = grp_assignment_read;
+ access->grp_hint = multiple_reads || total_scalarization;
access->grp_partial_lhs = grp_partial_lhs;
access->grp_unscalarizable_region = unscalarizable_region;
if (access->first_link)
ACCESS->replacement. */
static tree
-create_access_replacement (struct access *access)
+create_access_replacement (struct access *access, bool rename)
{
tree repl;
repl = create_tmp_var (access->type, "SR");
get_var_ann (repl);
add_referenced_var (repl);
- mark_sym_for_renaming (repl);
+ if (rename)
+ mark_sym_for_renaming (repl);
if (!access->grp_partial_lhs
&& (TREE_CODE (access->type) == COMPLEX_TYPE
DECL_SOURCE_LOCATION (repl) = DECL_SOURCE_LOCATION (access->base);
DECL_ARTIFICIAL (repl) = 1;
+ DECL_IGNORED_P (repl) = DECL_IGNORED_P (access->base);
if (DECL_NAME (access->base)
&& !DECL_IGNORED_P (access->base)
&& !DECL_ARTIFICIAL (access->base))
{
char *pretty_name = make_fancy_name (access->expr);
+ tree debug_expr = unshare_expr (access->expr), d;
DECL_NAME (repl) = get_identifier (pretty_name);
obstack_free (&name_obstack, pretty_name);
- SET_DECL_DEBUG_EXPR (repl, access->expr);
+ /* Get rid of any SSA_NAMEs embedded in debug_expr,
+ as DECL_DEBUG_EXPR isn't considered when looking for still
+ used SSA_NAMEs and thus they could be freed. All debug info
+ generation cares is whether something is constant or variable
+ and that get_ref_base_and_extent works properly on the
+ expression. */
+ for (d = debug_expr; handled_component_p (d); d = TREE_OPERAND (d, 0))
+ switch (TREE_CODE (d))
+ {
+ case ARRAY_REF:
+ case ARRAY_RANGE_REF:
+ if (TREE_OPERAND (d, 1)
+ && TREE_CODE (TREE_OPERAND (d, 1)) == SSA_NAME)
+ TREE_OPERAND (d, 1) = SSA_NAME_VAR (TREE_OPERAND (d, 1));
+ if (TREE_OPERAND (d, 3)
+ && TREE_CODE (TREE_OPERAND (d, 3)) == SSA_NAME)
+ TREE_OPERAND (d, 3) = SSA_NAME_VAR (TREE_OPERAND (d, 3));
+ /* FALLTHRU */
+ case COMPONENT_REF:
+ if (TREE_OPERAND (d, 2)
+ && TREE_CODE (TREE_OPERAND (d, 2)) == SSA_NAME)
+ TREE_OPERAND (d, 2) = SSA_NAME_VAR (TREE_OPERAND (d, 2));
+ break;
+ default:
+ break;
+ }
+ SET_DECL_DEBUG_EXPR (repl, debug_expr);
DECL_DEBUG_EXPR_IS_FROM (repl) = 1;
- DECL_IGNORED_P (repl) = 0;
+ TREE_NO_WARNING (repl) = TREE_NO_WARNING (access->base);
}
-
- DECL_IGNORED_P (repl) = DECL_IGNORED_P (access->base);
- TREE_NO_WARNING (repl) = TREE_NO_WARNING (access->base);
+ else
+ TREE_NO_WARNING (repl) = 1;
if (dump_file)
{
gcc_assert (access->grp_to_be_replaced);
if (!access->replacement_decl)
- access->replacement_decl = create_access_replacement (access);
+ access->replacement_decl = create_access_replacement (access, true);
+ return access->replacement_decl;
+}
+
+/* Return ACCESS scalar replacement, create it if it does not exist yet but do
+ not mark it for renaming. */
+
+static inline tree
+get_unrenamed_access_replacement (struct access *access)
+{
+ gcc_assert (!access->grp_to_be_replaced);
+
+ if (!access->replacement_decl)
+ access->replacement_decl = create_access_replacement (access, false);
return access->replacement_decl;
}
+
/* Build a subtree of accesses rooted in *ACCESS, and move the pointer in the
linked list along the way. Stop when *ACCESS is NULL or the access pointed
- to it is not "within" the root. */
+ to it is not "within" the root. Return false iff some accesses partially
+ overlap. */
-static void
+static bool
build_access_subtree (struct access **access)
{
struct access *root = *access, *last_child = NULL;
last_child->next_sibling = *access;
last_child = *access;
- build_access_subtree (access);
+ if (!build_access_subtree (access))
+ return false;
}
+
+ if (*access && (*access)->offset < limit)
+ return false;
+
+ return true;
}
/* Build a tree of access representatives, ACCESS is the pointer to the first
- one, others are linked in a list by the next_grp field. Decide about scalar
- replacements on the way, return true iff any are to be created. */
+ one, others are linked in a list by the next_grp field. Return false iff
+ some accesses partially overlap. */
-static void
+static bool
build_access_trees (struct access *access)
{
while (access)
{
struct access *root = access;
- build_access_subtree (&access);
+ if (!build_access_subtree (&access))
+ return false;
root->next_grp = access;
}
+ return true;
}
/* Return true if expr contains some ARRAY_REFs into a variable bounded
return false;
}
+enum mark_read_status { SRA_MR_NOT_READ, SRA_MR_READ, SRA_MR_ASSIGN_READ};
+
/* Analyze the subtree of accesses rooted in ROOT, scheduling replacements when
- both seeming beneficial and when ALLOW_REPLACEMENTS allows it. Also set
- all sorts of access flags appropriately along the way, notably always ser
- grp_read when MARK_READ is true and grp_write when MARK_WRITE is true. */
+ both seeming beneficial and when ALLOW_REPLACEMENTS allows it. Also set all
+ sorts of access flags appropriately along the way, notably always set
+ grp_read and grp_assign_read according to MARK_READ and grp_write when
+ MARK_WRITE is true. */
static bool
analyze_access_subtree (struct access *root, bool allow_replacements,
- bool mark_read, bool mark_write)
+ enum mark_read_status mark_read, bool mark_write)
{
struct access *child;
HOST_WIDE_INT limit = root->offset + root->size;
bool hole = false, sth_created = false;
bool direct_read = root->grp_read;
- if (mark_read)
- root->grp_read = true;
+ if (mark_read == SRA_MR_ASSIGN_READ)
+ {
+ root->grp_read = 1;
+ root->grp_assignment_read = 1;
+ }
+ if (mark_read == SRA_MR_READ)
+ root->grp_read = 1;
+ else if (root->grp_assignment_read)
+ mark_read = SRA_MR_ASSIGN_READ;
else if (root->grp_read)
- mark_read = true;
+ mark_read = SRA_MR_READ;
if (mark_write)
root->grp_write = true;
else
covered_to += child->size;
- sth_created |= analyze_access_subtree (child, allow_replacements,
+ sth_created |= analyze_access_subtree (child,
+ allow_replacements && !scalar,
mark_read, mark_write);
root->grp_unscalarized_data |= child->grp_unscalarized_data;
if (allow_replacements && scalar && !root->first_child
&& (root->grp_hint
- || (direct_read && root->grp_write)))
+ || (root->grp_write && (direct_read || root->grp_assignment_read)))
+ /* We must not ICE later on when trying to build an access to the
+ original data within the aggregate even when it is impossible to do in
+ a defined way like in the PR 42703 testcase. Therefore we check
+ pre-emptively here that we will be able to do that. */
+ && build_ref_for_offset (NULL, TREE_TYPE (root->base), root->offset,
+ root->type, false))
{
if (dump_file && (dump_flags & TDF_DETAILS))
{
while (access)
{
- if (analyze_access_subtree (access, true, false, false))
+ if (analyze_access_subtree (access, true, SRA_MR_NOT_READ, false))
ret = true;
access = access->next_grp;
}
/* Create a new child access of PARENT, with all properties just like MODEL
except for its offset and with its grp_write false and grp_read true.
- Return the new access. Note that this access is created long after all
- splicing and sorting, it's not located in any access vector and is
- automatically a representative of its group. */
+ Return the new access or NULL if it cannot be created. Note that this access
+ is created long after all splicing and sorting, it's not located in any
+ access vector and is automatically a representative of its group. */
static struct access *
create_artificial_child_access (struct access *parent, struct access *model,
{
struct access *access;
struct access **child;
- bool ok;
+ tree expr = parent->base;;
gcc_assert (!model->grp_unscalarizable_region);
+ if (!build_ref_for_offset (&expr, TREE_TYPE (expr), new_offset,
+ model->type, false))
+ return NULL;
+
access = (struct access *) pool_alloc (access_pool);
memset (access, 0, sizeof (struct access));
access->base = parent->base;
+ access->expr = expr;
access->offset = new_offset;
access->size = model->size;
access->type = model->type;
access->grp_write = true;
access->grp_read = false;
- access->expr = access->base;
- ok = build_ref_for_offset (&access->expr, TREE_TYPE (access->expr),
- new_offset, access->type, false);
- gcc_assert (ok);
child = &parent->first_child;
while (*child && (*child)->offset < new_offset)
/* Propagate all subaccesses of RACC across an assignment link to LACC. Return
true if any new subaccess was created. Additionally, if RACC is a scalar
- access but LACC is not, change the type of the latter. */
+ access but LACC is not, change the type of the latter, if possible. */
static bool
-propagate_subacesses_accross_link (struct access *lacc, struct access *racc)
+propagate_subaccesses_across_link (struct access *lacc, struct access *racc)
{
struct access *rchild;
HOST_WIDE_INT norm_delta = lacc->offset - racc->offset;
if (!lacc->first_child && !racc->first_child
&& is_gimple_reg_type (racc->type))
{
- bool ok;
+ tree t = lacc->base;
- lacc->expr = lacc->base;
- ok = build_ref_for_offset (&lacc->expr, TREE_TYPE (lacc->expr),
- lacc->offset, racc->type, false);
- gcc_assert (ok);
- lacc->type = racc->type;
+ if (build_ref_for_offset (&t, TREE_TYPE (t), lacc->offset, racc->type,
+ false))
+ {
+ lacc->expr = t;
+ lacc->type = racc->type;
+ }
return false;
}
rchild->grp_hint = 1;
new_acc->grp_hint |= new_acc->grp_read;
if (rchild->first_child)
- ret |= propagate_subacesses_accross_link (new_acc, rchild);
+ ret |= propagate_subaccesses_across_link (new_acc, rchild);
}
continue;
}
rchild->grp_hint = 1;
new_acc = create_artificial_child_access (lacc, rchild, norm_offset);
- if (racc->first_child)
- propagate_subacesses_accross_link (new_acc, rchild);
-
- ret = true;
+ if (new_acc)
+ {
+ ret = true;
+ if (racc->first_child)
+ propagate_subaccesses_across_link (new_acc, rchild);
+ }
}
return ret;
if (!bitmap_bit_p (candidate_bitmap, DECL_UID (lacc->base)))
continue;
lacc = lacc->group_representative;
- if (propagate_subacesses_accross_link (lacc, racc)
+ if (propagate_subaccesses_across_link (lacc, racc)
&& lacc->first_link)
add_access_to_work_queue (lacc);
}
static bool
analyze_all_variable_accesses (void)
{
- tree var;
- referenced_var_iterator rvi;
int res = 0;
+ bitmap tmp = BITMAP_ALLOC (NULL);
+ bitmap_iterator bi;
+ unsigned i, max_total_scalarization_size;
- FOR_EACH_REFERENCED_VAR (var, rvi)
- if (bitmap_bit_p (candidate_bitmap, DECL_UID (var)))
- {
- struct access *access;
-
- access = sort_and_splice_var_accesses (var);
- if (access)
- build_access_trees (access);
- else
- disqualify_candidate (var,
- "No or inhibitingly overlapping accesses.");
- }
-
- propagate_all_subaccesses ();
+ max_total_scalarization_size = UNITS_PER_WORD * BITS_PER_UNIT
+ * MOVE_RATIO (optimize_function_for_speed_p (cfun));
- FOR_EACH_REFERENCED_VAR (var, rvi)
- if (bitmap_bit_p (candidate_bitmap, DECL_UID (var)))
+ EXECUTE_IF_SET_IN_BITMAP (candidate_bitmap, 0, i, bi)
+ if (bitmap_bit_p (should_scalarize_away_bitmap, i)
+ && !bitmap_bit_p (cannot_scalarize_away_bitmap, i))
{
- struct access *access = get_first_repr_for_decl (var);
+ tree var = referenced_var (i);
- if (analyze_access_trees (access))
+ if (TREE_CODE (var) == VAR_DECL
+ && ((unsigned) tree_low_cst (TYPE_SIZE (TREE_TYPE (var)), 1)
+ <= max_total_scalarization_size)
+ && type_consists_of_records_p (TREE_TYPE (var)))
{
- res++;
+ completely_scalarize_record (var, var, 0);
if (dump_file && (dump_flags & TDF_DETAILS))
{
- fprintf (dump_file, "\nAccess trees for ");
+ fprintf (dump_file, "Will attempt to totally scalarize ");
print_generic_expr (dump_file, var, 0);
fprintf (dump_file, " (UID: %u): \n", DECL_UID (var));
- dump_access_tree (dump_file, access);
- fprintf (dump_file, "\n");
}
}
- else
- disqualify_candidate (var, "No scalar replacements to be created.");
}
- if (res)
+ bitmap_copy (tmp, candidate_bitmap);
+ EXECUTE_IF_SET_IN_BITMAP (tmp, 0, i, bi)
+ {
+ tree var = referenced_var (i);
+ struct access *access;
+
+ access = sort_and_splice_var_accesses (var);
+ if (!access || !build_access_trees (access))
+ disqualify_candidate (var,
+ "No or inhibitingly overlapping accesses.");
+ }
+
+ propagate_all_subaccesses ();
+
+ bitmap_copy (tmp, candidate_bitmap);
+ EXECUTE_IF_SET_IN_BITMAP (tmp, 0, i, bi)
+ {
+ tree var = referenced_var (i);
+ struct access *access = get_first_repr_for_decl (var);
+
+ if (analyze_access_trees (access))
+ {
+ res++;
+ if (dump_file && (dump_flags & TDF_DETAILS))
+ {
+ fprintf (dump_file, "\nAccess trees for ");
+ print_generic_expr (dump_file, var, 0);
+ fprintf (dump_file, " (UID: %u): \n", DECL_UID (var));
+ dump_access_tree (dump_file, access);
+ fprintf (dump_file, "\n");
+ }
+ }
+ else
+ disqualify_candidate (var, "No scalar replacements to be created.");
+ }
+
+ BITMAP_FREE (tmp);
+
+ if (res)
{
statistics_counter_event (cfun, "Scalarized aggregates", res);
return true;
{
do
{
- tree expr = unshare_expr (agg);
+ tree expr = agg;
if (chunk_size && access->offset >= start_offset + chunk_size)
return;
return get_var_base_offset_size_access (base, offset, max_size);
}
-/* Callback for scan_function. Replace the expression EXPR with a scalar
- replacement if there is one and generate other statements to do type
- conversion or subtree copying if necessary. GSI is used to place newly
- created statements, WRITE is true if the expression is being written to (it
- is on a LHS of a statement or output in an assembly statement). */
+/* Replace the expression EXPR with a scalar replacement if there is one and
+ generate other statements to do type conversion or subtree copying if
+ necessary. GSI is used to place newly created statements, WRITE is true if
+ the expression is being written to (it is on a LHS of a statement or output
+ in an assembly statement). */
static bool
-sra_modify_expr (tree *expr, gimple_stmt_iterator *gsi, bool write,
- void *data ATTRIBUTE_UNUSED)
+sra_modify_expr (tree *expr, gimple_stmt_iterator *gsi, bool write)
{
struct access *access;
tree type, bfr;
access expression to extract the scalar component afterwards.
This happens if scalarizing a function return value or parameter
like in gcc.c-torture/execute/20041124-1.c, 20050316-1.c and
- gcc.c-torture/compile/20011217-1.c. */
- if (!is_gimple_reg_type (type))
+ gcc.c-torture/compile/20011217-1.c.
+
+ We also want to use this when accessing a complex or vector which can
+ be accessed as a different type too, potentially creating a need for
+ type conversion (see PR42196) and when scalarized unions are involved
+ in assembler statements (see PR42398). */
+ if (!useless_type_conversion_p (type, access->type))
{
- gimple stmt;
+ tree ref = access->base;
+ bool ok;
+
+ ok = build_ref_for_offset (&ref, TREE_TYPE (ref),
+ access->offset, access->type, false);
+ gcc_assert (ok);
+
if (write)
{
- tree ref = unshare_expr (access->expr);
+ gimple stmt;
+
if (access->grp_partial_lhs)
ref = force_gimple_operand_gsi (gsi, ref, true, NULL_TREE,
false, GSI_NEW_STMT);
}
else
{
+ gimple stmt;
+
if (access->grp_partial_lhs)
repl = force_gimple_operand_gsi (gsi, repl, true, NULL_TREE,
true, GSI_SAME_STMT);
- stmt = gimple_build_assign (unshare_expr (access->expr), repl);
+ stmt = gimple_build_assign (ref, repl);
gsi_insert_before (gsi, stmt, GSI_SAME_STMT);
}
}
else
- {
- gcc_assert (useless_type_conversion_p (type, access->type));
- *expr = repl;
- }
+ *expr = repl;
sra_stats.exprs++;
}
}
else
{
- bool repl_found;
-
/* No suitable access on the right hand side, need to load from
the aggregate. See if we have to update it first... */
if (*refreshed == SRA_UDH_NONE)
lhs, old_gsi);
if (*refreshed == SRA_UDH_LEFT)
- rhs = unshare_expr (lacc->expr);
+ {
+ bool repl_found;
+
+ rhs = lacc->base;
+ repl_found = build_ref_for_offset (&rhs, TREE_TYPE (rhs),
+ lacc->offset, lacc->type,
+ false);
+ gcc_assert (repl_found);
+ }
else
{
- rhs = unshare_expr (top_racc->base);
+ bool repl_found;
+
+ rhs = top_racc->base;
repl_found = build_ref_for_offset (&rhs,
TREE_TYPE (top_racc->base),
offset, lacc->type, false);
while (lacc);
}
+/* Result code for SRA assignment modification. */
+enum assignment_mod_result { SRA_AM_NONE, /* nothing done for the stmt */
+ SRA_AM_MODIFIED, /* stmt changed but not
+ removed */
+ SRA_AM_REMOVED }; /* stmt eliminated */
+
/* Modify assignments with a CONSTRUCTOR on their RHS. STMT contains a pointer
to the assignment and GSI is the statement iterator pointing at it. Returns
the same values as sra_modify_assign. */
-static enum scan_assign_result
+static enum assignment_mod_result
sra_modify_constructor_assign (gimple *stmt, gimple_stmt_iterator *gsi)
{
tree lhs = gimple_assign_lhs (*stmt);
acc = get_access_for_expr (lhs);
if (!acc)
- return SRA_SA_NONE;
+ return SRA_AM_NONE;
if (VEC_length (constructor_elt,
CONSTRUCTOR_ELTS (gimple_assign_rhs1 (*stmt))) > 0)
if (access_has_children_p (acc))
generate_subtree_copies (acc->first_child, acc->base, 0, 0, 0, gsi,
true, true);
- return SRA_SA_PROCESSED;
+ return SRA_AM_MODIFIED;
}
if (acc->grp_covered)
init_subtree_with_zero (acc, gsi, false);
unlink_stmt_vdef (*stmt);
gsi_remove (gsi, true);
- return SRA_SA_REMOVED;
+ return SRA_AM_REMOVED;
}
else
{
init_subtree_with_zero (acc, gsi, true);
- return SRA_SA_PROCESSED;
+ return SRA_AM_MODIFIED;
}
}
+/* Create a new suitable default definition SSA_NAME and replace all uses of
+ SSA with it, RACC is access describing the uninitialized part of an
+ aggregate that is being loaded. */
+
+static void
+replace_uses_with_default_def_ssa_name (tree ssa, struct access *racc)
+{
+ tree repl, decl;
+
+ decl = get_unrenamed_access_replacement (racc);
+
+ repl = gimple_default_def (cfun, decl);
+ if (!repl)
+ {
+ repl = make_ssa_name (decl, gimple_build_nop ());
+ set_default_def (decl, repl);
+ }
+
+ replace_uses_by (ssa, repl);
+}
-/* Callback of scan_function to process assign statements. It examines both
- sides of the statement, replaces them with a scalare replacement if there is
- one and generating copying of replacements if scalarized aggregates have been
- used in the assignment. STMT is a pointer to the assign statement, GSI is
- used to hold generated statements for type conversions and subtree
+/* Examine both sides of the assignment statement pointed to by STMT, replace
+ them with a scalare replacement if there is one and generate copying of
+ replacements if scalarized aggregates have been used in the assignment. GSI
+ is used to hold generated statements for type conversions and subtree
copying. */
-static enum scan_assign_result
-sra_modify_assign (gimple *stmt, gimple_stmt_iterator *gsi,
- void *data ATTRIBUTE_UNUSED)
+static enum assignment_mod_result
+sra_modify_assign (gimple *stmt, gimple_stmt_iterator *gsi)
{
struct access *lacc, *racc;
tree lhs, rhs;
bool modify_this_stmt = false;
bool force_gimple_rhs = false;
location_t loc = gimple_location (*stmt);
+ gimple_stmt_iterator orig_gsi = *gsi;
if (!gimple_assign_single_p (*stmt))
- return SRA_SA_NONE;
+ return SRA_AM_NONE;
lhs = gimple_assign_lhs (*stmt);
rhs = gimple_assign_rhs1 (*stmt);
|| TREE_CODE (rhs) == BIT_FIELD_REF || TREE_CODE (lhs) == BIT_FIELD_REF)
{
modify_this_stmt = sra_modify_expr (gimple_assign_rhs1_ptr (*stmt),
- gsi, false, data);
+ gsi, false);
modify_this_stmt |= sra_modify_expr (gimple_assign_lhs_ptr (*stmt),
- gsi, true, data);
- return modify_this_stmt ? SRA_SA_PROCESSED : SRA_SA_NONE;
+ gsi, true);
+ return modify_this_stmt ? SRA_AM_MODIFIED : SRA_AM_NONE;
}
lacc = get_access_for_expr (lhs);
racc = get_access_for_expr (rhs);
if (!lacc && !racc)
- return SRA_SA_NONE;
+ return SRA_AM_NONE;
if (lacc && lacc->grp_to_be_replaced)
{
if (AGGREGATE_TYPE_P (TREE_TYPE (lhs))
&& !access_has_children_p (lacc))
{
- tree expr = unshare_expr (lhs);
+ tree expr = lhs;
if (build_ref_for_offset (&expr, TREE_TYPE (lhs), 0,
TREE_TYPE (rhs), false))
{
else if (AGGREGATE_TYPE_P (TREE_TYPE (rhs))
&& !access_has_children_p (racc))
{
- tree expr = unshare_expr (rhs);
+ tree expr = rhs;
if (build_ref_for_offset (&expr, TREE_TYPE (rhs), 0,
TREE_TYPE (lhs), false))
rhs = expr;
if (!useless_type_conversion_p (TREE_TYPE (lhs), TREE_TYPE (rhs)))
{
rhs = fold_build1_loc (loc, VIEW_CONVERT_EXPR, TREE_TYPE (lhs), rhs);
- if (!is_gimple_reg (lhs))
+ if (is_gimple_reg_type (TREE_TYPE (lhs))
+ && TREE_CODE (lhs) != SSA_NAME)
force_gimple_rhs = true;
}
}
-
- if (force_gimple_rhs)
- rhs = force_gimple_operand_gsi (gsi, rhs, true, NULL_TREE,
- true, GSI_SAME_STMT);
- if (gimple_assign_rhs1 (*stmt) != rhs)
- {
- gimple_assign_set_rhs_from_tree (gsi, rhs);
- gcc_assert (*stmt == gsi_stmt (*gsi));
- }
}
/* From this point on, the function deals with assignments in between
there to do the copying and then load the scalar replacements of the LHS.
This is what the first branch does. */
- if (contains_view_convert_expr_p (rhs) || contains_view_convert_expr_p (lhs)
+ if (gimple_has_volatile_ops (*stmt)
+ || contains_view_convert_expr_p (rhs)
+ || contains_view_convert_expr_p (lhs)
|| (access_has_children_p (racc)
&& !ref_expr_for_all_replacements_p (racc, lhs, racc->offset))
|| (access_has_children_p (lacc)
unlink_stmt_vdef (*stmt);
gsi_remove (&orig_gsi, true);
sra_stats.deleted++;
- return SRA_SA_REMOVED;
+ return SRA_AM_REMOVED;
}
}
else
{
- if (access_has_children_p (racc))
+ if (racc)
{
- if (!racc->grp_unscalarized_data)
+ if (!racc->grp_to_be_replaced && !racc->grp_unscalarized_data)
{
- generate_subtree_copies (racc->first_child, lhs,
- racc->offset, 0, 0, gsi,
- false, false);
+ if (racc->first_child)
+ generate_subtree_copies (racc->first_child, lhs,
+ racc->offset, 0, 0, gsi,
+ false, false);
gcc_assert (*stmt == gsi_stmt (*gsi));
+ if (TREE_CODE (lhs) == SSA_NAME)
+ replace_uses_with_default_def_ssa_name (lhs, racc);
+
unlink_stmt_vdef (*stmt);
gsi_remove (gsi, true);
sra_stats.deleted++;
- return SRA_SA_REMOVED;
+ return SRA_AM_REMOVED;
}
- else
+ else if (racc->first_child)
generate_subtree_copies (racc->first_child, lhs,
racc->offset, 0, 0, gsi, false, true);
}
- else if (access_has_children_p (lacc))
+ if (access_has_children_p (lacc))
generate_subtree_copies (lacc->first_child, rhs, lacc->offset,
0, 0, gsi, true, true);
}
}
- return modify_this_stmt ? SRA_SA_PROCESSED : SRA_SA_NONE;
+
+ /* This gimplification must be done after generate_subtree_copies, lest we
+ insert the subtree copies in the middle of the gimplified sequence. */
+ if (force_gimple_rhs)
+ rhs = force_gimple_operand_gsi (&orig_gsi, rhs, true, NULL_TREE,
+ true, GSI_SAME_STMT);
+ if (gimple_assign_rhs1 (*stmt) != rhs)
+ {
+ gimple_assign_set_rhs_from_tree (&orig_gsi, rhs);
+ gcc_assert (*stmt == gsi_stmt (orig_gsi));
+ }
+
+ return modify_this_stmt ? SRA_AM_MODIFIED : SRA_AM_NONE;
+}
+
+/* Traverse the function body and all modifications as decided in
+ analyze_all_variable_accesses. */
+
+static void
+sra_modify_function_body (void)
+{
+ basic_block bb;
+
+ FOR_EACH_BB (bb)
+ {
+ gimple_stmt_iterator gsi = gsi_start_bb (bb);
+ while (!gsi_end_p (gsi))
+ {
+ gimple stmt = gsi_stmt (gsi);
+ enum assignment_mod_result assign_result;
+ bool modified = false, deleted = false;
+ tree *t;
+ unsigned i;
+
+ switch (gimple_code (stmt))
+ {
+ case GIMPLE_RETURN:
+ t = gimple_return_retval_ptr (stmt);
+ if (*t != NULL_TREE)
+ modified |= sra_modify_expr (t, &gsi, false);
+ break;
+
+ case GIMPLE_ASSIGN:
+ assign_result = sra_modify_assign (&stmt, &gsi);
+ modified |= assign_result == SRA_AM_MODIFIED;
+ deleted = assign_result == SRA_AM_REMOVED;
+ break;
+
+ case GIMPLE_CALL:
+ /* Operands must be processed before the lhs. */
+ for (i = 0; i < gimple_call_num_args (stmt); i++)
+ {
+ t = gimple_call_arg_ptr (stmt, i);
+ modified |= sra_modify_expr (t, &gsi, false);
+ }
+
+ if (gimple_call_lhs (stmt))
+ {
+ t = gimple_call_lhs_ptr (stmt);
+ modified |= sra_modify_expr (t, &gsi, true);
+ }
+ break;
+
+ case GIMPLE_ASM:
+ for (i = 0; i < gimple_asm_ninputs (stmt); i++)
+ {
+ t = &TREE_VALUE (gimple_asm_input_op (stmt, i));
+ modified |= sra_modify_expr (t, &gsi, false);
+ }
+ for (i = 0; i < gimple_asm_noutputs (stmt); i++)
+ {
+ t = &TREE_VALUE (gimple_asm_output_op (stmt, i));
+ modified |= sra_modify_expr (t, &gsi, true);
+ }
+ break;
+
+ default:
+ break;
+ }
+
+ if (modified)
+ {
+ update_stmt (stmt);
+ maybe_clean_eh_stmt (stmt);
+ }
+ if (!deleted)
+ gsi_next (&gsi);
+ }
+ }
}
/* Generate statements initializing scalar replacements of parts of function
if (!find_var_candidates ())
goto out;
- if (!scan_function (build_access_from_expr, build_accesses_from_assign, NULL,
- true, NULL))
+ if (!scan_function ())
goto out;
if (!analyze_all_variable_accesses ())
goto out;
- scan_function (sra_modify_expr, sra_modify_assign, NULL,
- false, NULL);
+ sra_modify_function_body ();
initialize_parameter_reductions ();
statistics_counter_event (cfun, "Scalar replacements created",
static bool
gate_intra_sra (void)
{
- return flag_tree_sra != 0;
+ return flag_tree_sra != 0 && dbg_cnt (tree_sra);
}
}
};
-
struct gimple_opt_pass pass_sra =
{
{
| TODO_verify_ssa /* todo_flags_finish */
}
};
+
+
+/* Return true iff PARM (which must be a parm_decl) is an unused scalar
+ parameter. */
+
+static bool
+is_unused_scalar_param (tree parm)
+{
+ tree name;
+ return (is_gimple_reg (parm)
+ && (!(name = gimple_default_def (cfun, parm))
+ || has_zero_uses (name)));
+}
+
+/* Scan immediate uses of a default definition SSA name of a parameter PARM and
+ examine whether there are any direct or otherwise infeasible ones. If so,
+ return true, otherwise return false. PARM must be a gimple register with a
+ non-NULL default definition. */
+
+static bool
+ptr_parm_has_direct_uses (tree parm)
+{
+ imm_use_iterator ui;
+ gimple stmt;
+ tree name = gimple_default_def (cfun, parm);
+ bool ret = false;
+
+ FOR_EACH_IMM_USE_STMT (stmt, ui, name)
+ {
+ int uses_ok = 0;
+ use_operand_p use_p;
+
+ if (is_gimple_debug (stmt))
+ continue;
+
+ /* Valid uses include dereferences on the lhs and the rhs. */
+ if (gimple_has_lhs (stmt))
+ {
+ tree lhs = gimple_get_lhs (stmt);
+ while (handled_component_p (lhs))
+ lhs = TREE_OPERAND (lhs, 0);
+ if (INDIRECT_REF_P (lhs)
+ && TREE_OPERAND (lhs, 0) == name)
+ uses_ok++;
+ }
+ if (gimple_assign_single_p (stmt))
+ {
+ tree rhs = gimple_assign_rhs1 (stmt);
+ while (handled_component_p (rhs))
+ rhs = TREE_OPERAND (rhs, 0);
+ if (INDIRECT_REF_P (rhs)
+ && TREE_OPERAND (rhs, 0) == name)
+ uses_ok++;
+ }
+ else if (is_gimple_call (stmt))
+ {
+ unsigned i;
+ for (i = 0; i < gimple_call_num_args (stmt); ++i)
+ {
+ tree arg = gimple_call_arg (stmt, i);
+ while (handled_component_p (arg))
+ arg = TREE_OPERAND (arg, 0);
+ if (INDIRECT_REF_P (arg)
+ && TREE_OPERAND (arg, 0) == name)
+ uses_ok++;
+ }
+ }
+
+ /* If the number of valid uses does not match the number of
+ uses in this stmt there is an unhandled use. */
+ FOR_EACH_IMM_USE_ON_STMT (use_p, ui)
+ --uses_ok;
+
+ if (uses_ok != 0)
+ ret = true;
+
+ if (ret)
+ BREAK_FROM_IMM_USE_STMT (ui);
+ }
+
+ return ret;
+}
+
+/* Identify candidates for reduction for IPA-SRA based on their type and mark
+ them in candidate_bitmap. Note that these do not necessarily include
+ parameter which are unused and thus can be removed. Return true iff any
+ such candidate has been found. */
+
+static bool
+find_param_candidates (void)
+{
+ tree parm;
+ int count = 0;
+ bool ret = false;
+
+ for (parm = DECL_ARGUMENTS (current_function_decl);
+ parm;
+ parm = TREE_CHAIN (parm))
+ {
+ tree type = TREE_TYPE (parm);
+
+ count++;
+
+ if (TREE_THIS_VOLATILE (parm)
+ || TREE_ADDRESSABLE (parm)
+ || (!is_gimple_reg_type (type) && is_va_list_type (type)))
+ continue;
+
+ if (is_unused_scalar_param (parm))
+ {
+ ret = true;
+ continue;
+ }
+
+ if (POINTER_TYPE_P (type))
+ {
+ type = TREE_TYPE (type);
+
+ if (TREE_CODE (type) == FUNCTION_TYPE
+ || TYPE_VOLATILE (type)
+ || !is_gimple_reg (parm)
+ || is_va_list_type (type)
+ || ptr_parm_has_direct_uses (parm))
+ continue;
+ }
+ else if (!AGGREGATE_TYPE_P (type))
+ continue;
+
+ if (!COMPLETE_TYPE_P (type)
+ || !host_integerp (TYPE_SIZE (type), 1)
+ || tree_low_cst (TYPE_SIZE (type), 1) == 0
+ || (AGGREGATE_TYPE_P (type)
+ && type_internals_preclude_sra_p (type)))
+ continue;
+
+ bitmap_set_bit (candidate_bitmap, DECL_UID (parm));
+ ret = true;
+ if (dump_file && (dump_flags & TDF_DETAILS))
+ {
+ fprintf (dump_file, "Candidate (%d): ", DECL_UID (parm));
+ print_generic_expr (dump_file, parm, 0);
+ fprintf (dump_file, "\n");
+ }
+ }
+
+ func_param_count = count;
+ return ret;
+}
+
+/* Callback of walk_aliased_vdefs, marks the access passed as DATA as
+ maybe_modified. */
+
+static bool
+mark_maybe_modified (ao_ref *ao ATTRIBUTE_UNUSED, tree vdef ATTRIBUTE_UNUSED,
+ void *data)
+{
+ struct access *repr = (struct access *) data;
+
+ repr->grp_maybe_modified = 1;
+ return true;
+}
+
+/* Analyze what representatives (in linked lists accessible from
+ REPRESENTATIVES) can be modified by side effects of statements in the
+ current function. */
+
+static void
+analyze_modified_params (VEC (access_p, heap) *representatives)
+{
+ int i;
+
+ for (i = 0; i < func_param_count; i++)
+ {
+ struct access *repr;
+
+ for (repr = VEC_index (access_p, representatives, i);
+ repr;
+ repr = repr->next_grp)
+ {
+ struct access *access;
+ bitmap visited;
+ ao_ref ar;
+
+ if (no_accesses_p (repr))
+ continue;
+ if (!POINTER_TYPE_P (TREE_TYPE (repr->base))
+ || repr->grp_maybe_modified)
+ continue;
+
+ ao_ref_init (&ar, repr->expr);
+ visited = BITMAP_ALLOC (NULL);
+ for (access = repr; access; access = access->next_sibling)
+ {
+ /* All accesses are read ones, otherwise grp_maybe_modified would
+ be trivially set. */
+ walk_aliased_vdefs (&ar, gimple_vuse (access->stmt),
+ mark_maybe_modified, repr, &visited);
+ if (repr->grp_maybe_modified)
+ break;
+ }
+ BITMAP_FREE (visited);
+ }
+ }
+}
+
+/* Propagate distances in bb_dereferences in the opposite direction than the
+ control flow edges, in each step storing the maximum of the current value
+ and the minimum of all successors. These steps are repeated until the table
+ stabilizes. Note that BBs which might terminate the functions (according to
+ final_bbs bitmap) never updated in this way. */
+
+static void
+propagate_dereference_distances (void)
+{
+ VEC (basic_block, heap) *queue;
+ basic_block bb;
+
+ queue = VEC_alloc (basic_block, heap, last_basic_block_for_function (cfun));
+ VEC_quick_push (basic_block, queue, ENTRY_BLOCK_PTR);
+ FOR_EACH_BB (bb)
+ {
+ VEC_quick_push (basic_block, queue, bb);
+ bb->aux = bb;
+ }
+
+ while (!VEC_empty (basic_block, queue))
+ {
+ edge_iterator ei;
+ edge e;
+ bool change = false;
+ int i;
+
+ bb = VEC_pop (basic_block, queue);
+ bb->aux = NULL;
+
+ if (bitmap_bit_p (final_bbs, bb->index))
+ continue;
+
+ for (i = 0; i < func_param_count; i++)
+ {
+ int idx = bb->index * func_param_count + i;
+ bool first = true;
+ HOST_WIDE_INT inh = 0;
+
+ FOR_EACH_EDGE (e, ei, bb->succs)
+ {
+ int succ_idx = e->dest->index * func_param_count + i;
+
+ if (e->src == EXIT_BLOCK_PTR)
+ continue;
+
+ if (first)
+ {
+ first = false;
+ inh = bb_dereferences [succ_idx];
+ }
+ else if (bb_dereferences [succ_idx] < inh)
+ inh = bb_dereferences [succ_idx];
+ }
+
+ if (!first && bb_dereferences[idx] < inh)
+ {
+ bb_dereferences[idx] = inh;
+ change = true;
+ }
+ }
+
+ if (change && !bitmap_bit_p (final_bbs, bb->index))
+ FOR_EACH_EDGE (e, ei, bb->preds)
+ {
+ if (e->src->aux)
+ continue;
+
+ e->src->aux = e->src;
+ VEC_quick_push (basic_block, queue, e->src);
+ }
+ }
+
+ VEC_free (basic_block, heap, queue);
+}
+
+/* Dump a dereferences TABLE with heading STR to file F. */
+
+static void
+dump_dereferences_table (FILE *f, const char *str, HOST_WIDE_INT *table)
+{
+ basic_block bb;
+
+ fprintf (dump_file, str);
+ FOR_BB_BETWEEN (bb, ENTRY_BLOCK_PTR, EXIT_BLOCK_PTR, next_bb)
+ {
+ fprintf (f, "%4i %i ", bb->index, bitmap_bit_p (final_bbs, bb->index));
+ if (bb != EXIT_BLOCK_PTR)
+ {
+ int i;
+ for (i = 0; i < func_param_count; i++)
+ {
+ int idx = bb->index * func_param_count + i;
+ fprintf (f, " %4" HOST_WIDE_INT_PRINT "d", table[idx]);
+ }
+ }
+ fprintf (f, "\n");
+ }
+ fprintf (dump_file, "\n");
+}
+
+/* Determine what (parts of) parameters passed by reference that are not
+ assigned to are not certainly dereferenced in this function and thus the
+ dereferencing cannot be safely moved to the caller without potentially
+ introducing a segfault. Mark such REPRESENTATIVES as
+ grp_not_necessarilly_dereferenced.
+
+ The dereferenced maximum "distance," i.e. the offset + size of the accessed
+ part is calculated rather than simple booleans are calculated for each
+ pointer parameter to handle cases when only a fraction of the whole
+ aggregate is allocated (see testsuite/gcc.c-torture/execute/ipa-sra-2.c for
+ an example).
+
+ The maximum dereference distances for each pointer parameter and BB are
+ already stored in bb_dereference. This routine simply propagates these
+ values upwards by propagate_dereference_distances and then compares the
+ distances of individual parameters in the ENTRY BB to the equivalent
+ distances of each representative of a (fraction of a) parameter. */
+
+static void
+analyze_caller_dereference_legality (VEC (access_p, heap) *representatives)
+{
+ int i;
+
+ if (dump_file && (dump_flags & TDF_DETAILS))
+ dump_dereferences_table (dump_file,
+ "Dereference table before propagation:\n",
+ bb_dereferences);
+
+ propagate_dereference_distances ();
+
+ if (dump_file && (dump_flags & TDF_DETAILS))
+ dump_dereferences_table (dump_file,
+ "Dereference table after propagation:\n",
+ bb_dereferences);
+
+ for (i = 0; i < func_param_count; i++)
+ {
+ struct access *repr = VEC_index (access_p, representatives, i);
+ int idx = ENTRY_BLOCK_PTR->index * func_param_count + i;
+
+ if (!repr || no_accesses_p (repr))
+ continue;
+
+ do
+ {
+ if ((repr->offset + repr->size) > bb_dereferences[idx])
+ repr->grp_not_necessarilly_dereferenced = 1;
+ repr = repr->next_grp;
+ }
+ while (repr);
+ }
+}
+
+/* Return the representative access for the parameter declaration PARM if it is
+ a scalar passed by reference which is not written to and the pointer value
+ is not used directly. Thus, if it is legal to dereference it in the caller
+ and we can rule out modifications through aliases, such parameter should be
+ turned into one passed by value. Return NULL otherwise. */
+
+static struct access *
+unmodified_by_ref_scalar_representative (tree parm)
+{
+ int i, access_count;
+ struct access *repr;
+ VEC (access_p, heap) *access_vec;
+
+ access_vec = get_base_access_vector (parm);
+ gcc_assert (access_vec);
+ repr = VEC_index (access_p, access_vec, 0);
+ if (repr->write)
+ return NULL;
+ repr->group_representative = repr;
+
+ access_count = VEC_length (access_p, access_vec);
+ for (i = 1; i < access_count; i++)
+ {
+ struct access *access = VEC_index (access_p, access_vec, i);
+ if (access->write)
+ return NULL;
+ access->group_representative = repr;
+ access->next_sibling = repr->next_sibling;
+ repr->next_sibling = access;
+ }
+
+ repr->grp_read = 1;
+ repr->grp_scalar_ptr = 1;
+ return repr;
+}
+
+/* Return true iff this access precludes IPA-SRA of the parameter it is
+ associated with. */
+
+static bool
+access_precludes_ipa_sra_p (struct access *access)
+{
+ /* Avoid issues such as the second simple testcase in PR 42025. The problem
+ is incompatible assign in a call statement (and possibly even in asm
+ statements). This can be relaxed by using a new temporary but only for
+ non-TREE_ADDRESSABLE types and is probably not worth the complexity. (In
+ intraprocedural SRA we deal with this by keeping the old aggregate around,
+ something we cannot do in IPA-SRA.) */
+ if (access->write
+ && (is_gimple_call (access->stmt)
+ || gimple_code (access->stmt) == GIMPLE_ASM))
+ return true;
+
+ return false;
+}
+
+
+/* Sort collected accesses for parameter PARM, identify representatives for
+ each accessed region and link them together. Return NULL if there are
+ different but overlapping accesses, return the special ptr value meaning
+ there are no accesses for this parameter if that is the case and return the
+ first representative otherwise. Set *RO_GRP if there is a group of accesses
+ with only read (i.e. no write) accesses. */
+
+static struct access *
+splice_param_accesses (tree parm, bool *ro_grp)
+{
+ int i, j, access_count, group_count;
+ int agg_size, total_size = 0;
+ struct access *access, *res, **prev_acc_ptr = &res;
+ VEC (access_p, heap) *access_vec;
+
+ access_vec = get_base_access_vector (parm);
+ if (!access_vec)
+ return &no_accesses_representant;
+ access_count = VEC_length (access_p, access_vec);
+
+ qsort (VEC_address (access_p, access_vec), access_count, sizeof (access_p),
+ compare_access_positions);
+
+ i = 0;
+ total_size = 0;
+ group_count = 0;
+ while (i < access_count)
+ {
+ bool modification;
+ access = VEC_index (access_p, access_vec, i);
+ modification = access->write;
+ if (access_precludes_ipa_sra_p (access))
+ return NULL;
+
+ /* Access is about to become group representative unless we find some
+ nasty overlap which would preclude us from breaking this parameter
+ apart. */
+
+ j = i + 1;
+ while (j < access_count)
+ {
+ struct access *ac2 = VEC_index (access_p, access_vec, j);
+ if (ac2->offset != access->offset)
+ {
+ /* All or nothing law for parameters. */
+ if (access->offset + access->size > ac2->offset)
+ return NULL;
+ else
+ break;
+ }
+ else if (ac2->size != access->size)
+ return NULL;
+
+ if (access_precludes_ipa_sra_p (ac2))
+ return NULL;
+
+ modification |= ac2->write;
+ ac2->group_representative = access;
+ ac2->next_sibling = access->next_sibling;
+ access->next_sibling = ac2;
+ j++;
+ }
+
+ group_count++;
+ access->grp_maybe_modified = modification;
+ if (!modification)
+ *ro_grp = true;
+ *prev_acc_ptr = access;
+ prev_acc_ptr = &access->next_grp;
+ total_size += access->size;
+ i = j;
+ }
+
+ if (POINTER_TYPE_P (TREE_TYPE (parm)))
+ agg_size = tree_low_cst (TYPE_SIZE (TREE_TYPE (TREE_TYPE (parm))), 1);
+ else
+ agg_size = tree_low_cst (TYPE_SIZE (TREE_TYPE (parm)), 1);
+ if (total_size >= agg_size)
+ return NULL;
+
+ gcc_assert (group_count > 0);
+ return res;
+}
+
+/* Decide whether parameters with representative accesses given by REPR should
+ be reduced into components. */
+
+static int
+decide_one_param_reduction (struct access *repr)
+{
+ int total_size, cur_parm_size, agg_size, new_param_count, parm_size_limit;
+ bool by_ref;
+ tree parm;
+
+ parm = repr->base;
+ cur_parm_size = tree_low_cst (TYPE_SIZE (TREE_TYPE (parm)), 1);
+ gcc_assert (cur_parm_size > 0);
+
+ if (POINTER_TYPE_P (TREE_TYPE (parm)))
+ {
+ by_ref = true;
+ agg_size = tree_low_cst (TYPE_SIZE (TREE_TYPE (TREE_TYPE (parm))), 1);
+ }
+ else
+ {
+ by_ref = false;
+ agg_size = cur_parm_size;
+ }
+
+ if (dump_file)
+ {
+ struct access *acc;
+ fprintf (dump_file, "Evaluating PARAM group sizes for ");
+ print_generic_expr (dump_file, parm, 0);
+ fprintf (dump_file, " (UID: %u): \n", DECL_UID (parm));
+ for (acc = repr; acc; acc = acc->next_grp)
+ dump_access (dump_file, acc, true);
+ }
+
+ total_size = 0;
+ new_param_count = 0;
+
+ for (; repr; repr = repr->next_grp)
+ {
+ gcc_assert (parm == repr->base);
+ new_param_count++;
+
+ if (!by_ref || (!repr->grp_maybe_modified
+ && !repr->grp_not_necessarilly_dereferenced))
+ total_size += repr->size;
+ else
+ total_size += cur_parm_size;
+ }
+
+ gcc_assert (new_param_count > 0);
+
+ if (optimize_function_for_size_p (cfun))
+ parm_size_limit = cur_parm_size;
+ else
+ parm_size_limit = (PARAM_VALUE (PARAM_IPA_SRA_PTR_GROWTH_FACTOR)
+ * cur_parm_size);
+
+ if (total_size < agg_size
+ && total_size <= parm_size_limit)
+ {
+ if (dump_file)
+ fprintf (dump_file, " ....will be split into %i components\n",
+ new_param_count);
+ return new_param_count;
+ }
+ else
+ return 0;
+}
+
+/* The order of the following enums is important, we need to do extra work for
+ UNUSED_PARAMS, BY_VAL_ACCESSES and UNMODIF_BY_REF_ACCESSES. */
+enum ipa_splicing_result { NO_GOOD_ACCESS, UNUSED_PARAMS, BY_VAL_ACCESSES,
+ MODIF_BY_REF_ACCESSES, UNMODIF_BY_REF_ACCESSES };
+
+/* Identify representatives of all accesses to all candidate parameters for
+ IPA-SRA. Return result based on what representatives have been found. */
+
+static enum ipa_splicing_result
+splice_all_param_accesses (VEC (access_p, heap) **representatives)
+{
+ enum ipa_splicing_result result = NO_GOOD_ACCESS;
+ tree parm;
+ struct access *repr;
+
+ *representatives = VEC_alloc (access_p, heap, func_param_count);
+
+ for (parm = DECL_ARGUMENTS (current_function_decl);
+ parm;
+ parm = TREE_CHAIN (parm))
+ {
+ if (is_unused_scalar_param (parm))
+ {
+ VEC_quick_push (access_p, *representatives,
+ &no_accesses_representant);
+ if (result == NO_GOOD_ACCESS)
+ result = UNUSED_PARAMS;
+ }
+ else if (POINTER_TYPE_P (TREE_TYPE (parm))
+ && is_gimple_reg_type (TREE_TYPE (TREE_TYPE (parm)))
+ && bitmap_bit_p (candidate_bitmap, DECL_UID (parm)))
+ {
+ repr = unmodified_by_ref_scalar_representative (parm);
+ VEC_quick_push (access_p, *representatives, repr);
+ if (repr)
+ result = UNMODIF_BY_REF_ACCESSES;
+ }
+ else if (bitmap_bit_p (candidate_bitmap, DECL_UID (parm)))
+ {
+ bool ro_grp = false;
+ repr = splice_param_accesses (parm, &ro_grp);
+ VEC_quick_push (access_p, *representatives, repr);
+
+ if (repr && !no_accesses_p (repr))
+ {
+ if (POINTER_TYPE_P (TREE_TYPE (parm)))
+ {
+ if (ro_grp)
+ result = UNMODIF_BY_REF_ACCESSES;
+ else if (result < MODIF_BY_REF_ACCESSES)
+ result = MODIF_BY_REF_ACCESSES;
+ }
+ else if (result < BY_VAL_ACCESSES)
+ result = BY_VAL_ACCESSES;
+ }
+ else if (no_accesses_p (repr) && (result == NO_GOOD_ACCESS))
+ result = UNUSED_PARAMS;
+ }
+ else
+ VEC_quick_push (access_p, *representatives, NULL);
+ }
+
+ if (result == NO_GOOD_ACCESS)
+ {
+ VEC_free (access_p, heap, *representatives);
+ *representatives = NULL;
+ return NO_GOOD_ACCESS;
+ }
+
+ return result;
+}
+
+/* Return the index of BASE in PARMS. Abort if it is not found. */
+
+static inline int
+get_param_index (tree base, VEC(tree, heap) *parms)
+{
+ int i, len;
+
+ len = VEC_length (tree, parms);
+ for (i = 0; i < len; i++)
+ if (VEC_index (tree, parms, i) == base)
+ return i;
+ gcc_unreachable ();
+}
+
+/* Convert the decisions made at the representative level into compact
+ parameter adjustments. REPRESENTATIVES are pointers to first
+ representatives of each param accesses, ADJUSTMENTS_COUNT is the expected
+ final number of adjustments. */
+
+static ipa_parm_adjustment_vec
+turn_representatives_into_adjustments (VEC (access_p, heap) *representatives,
+ int adjustments_count)
+{
+ VEC (tree, heap) *parms;
+ ipa_parm_adjustment_vec adjustments;
+ tree parm;
+ int i;
+
+ gcc_assert (adjustments_count > 0);
+ parms = ipa_get_vector_of_formal_parms (current_function_decl);
+ adjustments = VEC_alloc (ipa_parm_adjustment_t, heap, adjustments_count);
+ parm = DECL_ARGUMENTS (current_function_decl);
+ for (i = 0; i < func_param_count; i++, parm = TREE_CHAIN (parm))
+ {
+ struct access *repr = VEC_index (access_p, representatives, i);
+
+ if (!repr || no_accesses_p (repr))
+ {
+ struct ipa_parm_adjustment *adj;
+
+ adj = VEC_quick_push (ipa_parm_adjustment_t, adjustments, NULL);
+ memset (adj, 0, sizeof (*adj));
+ adj->base_index = get_param_index (parm, parms);
+ adj->base = parm;
+ if (!repr)
+ adj->copy_param = 1;
+ else
+ adj->remove_param = 1;
+ }
+ else
+ {
+ struct ipa_parm_adjustment *adj;
+ int index = get_param_index (parm, parms);
+
+ for (; repr; repr = repr->next_grp)
+ {
+ adj = VEC_quick_push (ipa_parm_adjustment_t, adjustments, NULL);
+ memset (adj, 0, sizeof (*adj));
+ gcc_assert (repr->base == parm);
+ adj->base_index = index;
+ adj->base = repr->base;
+ adj->type = repr->type;
+ adj->offset = repr->offset;
+ adj->by_ref = (POINTER_TYPE_P (TREE_TYPE (repr->base))
+ && (repr->grp_maybe_modified
+ || repr->grp_not_necessarilly_dereferenced));
+
+ }
+ }
+ }
+ VEC_free (tree, heap, parms);
+ return adjustments;
+}
+
+/* Analyze the collected accesses and produce a plan what to do with the
+ parameters in the form of adjustments, NULL meaning nothing. */
+
+static ipa_parm_adjustment_vec
+analyze_all_param_acesses (void)
+{
+ enum ipa_splicing_result repr_state;
+ bool proceed = false;
+ int i, adjustments_count = 0;
+ VEC (access_p, heap) *representatives;
+ ipa_parm_adjustment_vec adjustments;
+
+ repr_state = splice_all_param_accesses (&representatives);
+ if (repr_state == NO_GOOD_ACCESS)
+ return NULL;
+
+ /* If there are any parameters passed by reference which are not modified
+ directly, we need to check whether they can be modified indirectly. */
+ if (repr_state == UNMODIF_BY_REF_ACCESSES)
+ {
+ analyze_caller_dereference_legality (representatives);
+ analyze_modified_params (representatives);
+ }
+
+ for (i = 0; i < func_param_count; i++)
+ {
+ struct access *repr = VEC_index (access_p, representatives, i);
+
+ if (repr && !no_accesses_p (repr))
+ {
+ if (repr->grp_scalar_ptr)
+ {
+ adjustments_count++;
+ if (repr->grp_not_necessarilly_dereferenced
+ || repr->grp_maybe_modified)
+ VEC_replace (access_p, representatives, i, NULL);
+ else
+ {
+ proceed = true;
+ sra_stats.scalar_by_ref_to_by_val++;
+ }
+ }
+ else
+ {
+ int new_components = decide_one_param_reduction (repr);
+
+ if (new_components == 0)
+ {
+ VEC_replace (access_p, representatives, i, NULL);
+ adjustments_count++;
+ }
+ else
+ {
+ adjustments_count += new_components;
+ sra_stats.aggregate_params_reduced++;
+ sra_stats.param_reductions_created += new_components;
+ proceed = true;
+ }
+ }
+ }
+ else
+ {
+ if (no_accesses_p (repr))
+ {
+ proceed = true;
+ sra_stats.deleted_unused_parameters++;
+ }
+ adjustments_count++;
+ }
+ }
+
+ if (!proceed && dump_file)
+ fprintf (dump_file, "NOT proceeding to change params.\n");
+
+ if (proceed)
+ adjustments = turn_representatives_into_adjustments (representatives,
+ adjustments_count);
+ else
+ adjustments = NULL;
+
+ VEC_free (access_p, heap, representatives);
+ return adjustments;
+}
+
+/* If a parameter replacement identified by ADJ does not yet exist in the form
+ of declaration, create it and record it, otherwise return the previously
+ created one. */
+
+static tree
+get_replaced_param_substitute (struct ipa_parm_adjustment *adj)
+{
+ tree repl;
+ if (!adj->new_ssa_base)
+ {
+ char *pretty_name = make_fancy_name (adj->base);
+
+ repl = create_tmp_reg (TREE_TYPE (adj->base), "ISR");
+ DECL_NAME (repl) = get_identifier (pretty_name);
+ obstack_free (&name_obstack, pretty_name);
+
+ get_var_ann (repl);
+ add_referenced_var (repl);
+ adj->new_ssa_base = repl;
+ }
+ else
+ repl = adj->new_ssa_base;
+ return repl;
+}
+
+/* Find the first adjustment for a particular parameter BASE in a vector of
+ ADJUSTMENTS which is not a copy_param. Return NULL if there is no such
+ adjustment. */
+
+static struct ipa_parm_adjustment *
+get_adjustment_for_base (ipa_parm_adjustment_vec adjustments, tree base)
+{
+ int i, len;
+
+ len = VEC_length (ipa_parm_adjustment_t, adjustments);
+ for (i = 0; i < len; i++)
+ {
+ struct ipa_parm_adjustment *adj;
+
+ adj = VEC_index (ipa_parm_adjustment_t, adjustments, i);
+ if (!adj->copy_param && adj->base == base)
+ return adj;
+ }
+
+ return NULL;
+}
+
+/* If the statement STMT defines an SSA_NAME of a parameter which is to be
+ removed because its value is not used, replace the SSA_NAME with a one
+ relating to a created VAR_DECL together all of its uses and return true.
+ ADJUSTMENTS is a pointer to an adjustments vector. */
+
+static bool
+replace_removed_params_ssa_names (gimple stmt,
+ ipa_parm_adjustment_vec adjustments)
+{
+ struct ipa_parm_adjustment *adj;
+ tree lhs, decl, repl, name;
+
+ if (gimple_code (stmt) == GIMPLE_PHI)
+ lhs = gimple_phi_result (stmt);
+ else if (is_gimple_assign (stmt))
+ lhs = gimple_assign_lhs (stmt);
+ else if (is_gimple_call (stmt))
+ lhs = gimple_call_lhs (stmt);
+ else
+ gcc_unreachable ();
+
+ if (TREE_CODE (lhs) != SSA_NAME)
+ return false;
+ decl = SSA_NAME_VAR (lhs);
+ if (TREE_CODE (decl) != PARM_DECL)
+ return false;
+
+ adj = get_adjustment_for_base (adjustments, decl);
+ if (!adj)
+ return false;
+
+ repl = get_replaced_param_substitute (adj);
+ name = make_ssa_name (repl, stmt);
+
+ if (dump_file)
+ {
+ fprintf (dump_file, "replacing an SSA name of a removed param ");
+ print_generic_expr (dump_file, lhs, 0);
+ fprintf (dump_file, " with ");
+ print_generic_expr (dump_file, name, 0);
+ fprintf (dump_file, "\n");
+ }
+
+ if (is_gimple_assign (stmt))
+ gimple_assign_set_lhs (stmt, name);
+ else if (is_gimple_call (stmt))
+ gimple_call_set_lhs (stmt, name);
+ else
+ gimple_phi_set_result (stmt, name);
+
+ replace_uses_by (lhs, name);
+ release_ssa_name (lhs);
+ return true;
+}
+
+/* If the expression *EXPR should be replaced by a reduction of a parameter, do
+ so. ADJUSTMENTS is a pointer to a vector of adjustments. CONVERT
+ specifies whether the function should care about type incompatibility the
+ current and new expressions. If it is false, the function will leave
+ incompatibility issues to the caller. Return true iff the expression
+ was modified. */
+
+static bool
+sra_ipa_modify_expr (tree *expr, bool convert,
+ ipa_parm_adjustment_vec adjustments)
+{
+ int i, len;
+ struct ipa_parm_adjustment *adj, *cand = NULL;
+ HOST_WIDE_INT offset, size, max_size;
+ tree base, src;
+
+ len = VEC_length (ipa_parm_adjustment_t, adjustments);
+
+ if (TREE_CODE (*expr) == BIT_FIELD_REF
+ || TREE_CODE (*expr) == IMAGPART_EXPR
+ || TREE_CODE (*expr) == REALPART_EXPR)
+ {
+ expr = &TREE_OPERAND (*expr, 0);
+ convert = true;
+ }
+
+ base = get_ref_base_and_extent (*expr, &offset, &size, &max_size);
+ if (!base || size == -1 || max_size == -1)
+ return false;
+
+ if (INDIRECT_REF_P (base))
+ base = TREE_OPERAND (base, 0);
+
+ base = get_ssa_base_param (base);
+ if (!base || TREE_CODE (base) != PARM_DECL)
+ return false;
+
+ for (i = 0; i < len; i++)
+ {
+ adj = VEC_index (ipa_parm_adjustment_t, adjustments, i);
+
+ if (adj->base == base &&
+ (adj->offset == offset || adj->remove_param))
+ {
+ cand = adj;
+ break;
+ }
+ }
+ if (!cand || cand->copy_param || cand->remove_param)
+ return false;
+
+ if (cand->by_ref)
+ {
+ tree folded;
+ src = build1 (INDIRECT_REF, TREE_TYPE (TREE_TYPE (cand->reduction)),
+ cand->reduction);
+ folded = gimple_fold_indirect_ref (src);
+ if (folded)
+ src = folded;
+ }
+ else
+ src = cand->reduction;
+
+ if (dump_file && (dump_flags & TDF_DETAILS))
+ {
+ fprintf (dump_file, "About to replace expr ");
+ print_generic_expr (dump_file, *expr, 0);
+ fprintf (dump_file, " with ");
+ print_generic_expr (dump_file, src, 0);
+ fprintf (dump_file, "\n");
+ }
+
+ if (convert && !useless_type_conversion_p (TREE_TYPE (*expr), cand->type))
+ {
+ tree vce = build1 (VIEW_CONVERT_EXPR, TREE_TYPE (*expr), src);
+ *expr = vce;
+ }
+ else
+ *expr = src;
+ return true;
+}
+
+/* If the statement pointed to by STMT_PTR contains any expressions that need
+ to replaced with a different one as noted by ADJUSTMENTS, do so. Handle any
+ potential type incompatibilities (GSI is used to accommodate conversion
+ statements and must point to the statement). Return true iff the statement
+ was modified. */
+
+static bool
+sra_ipa_modify_assign (gimple *stmt_ptr, gimple_stmt_iterator *gsi,
+ ipa_parm_adjustment_vec adjustments)
+{
+ gimple stmt = *stmt_ptr;
+ tree *lhs_p, *rhs_p;
+ bool any;
+
+ if (!gimple_assign_single_p (stmt))
+ return false;
+
+ rhs_p = gimple_assign_rhs1_ptr (stmt);
+ lhs_p = gimple_assign_lhs_ptr (stmt);
+
+ any = sra_ipa_modify_expr (rhs_p, false, adjustments);
+ any |= sra_ipa_modify_expr (lhs_p, false, adjustments);
+ if (any)
+ {
+ tree new_rhs = NULL_TREE;
+
+ if (!useless_type_conversion_p (TREE_TYPE (*lhs_p), TREE_TYPE (*rhs_p)))
+ {
+ if (TREE_CODE (*rhs_p) == CONSTRUCTOR)
+ {
+ /* V_C_Es of constructors can cause trouble (PR 42714). */
+ if (is_gimple_reg_type (TREE_TYPE (*lhs_p)))
+ *rhs_p = fold_convert (TREE_TYPE (*lhs_p), integer_zero_node);
+ else
+ *rhs_p = build_constructor (TREE_TYPE (*lhs_p), 0);
+ }
+ else
+ new_rhs = fold_build1_loc (gimple_location (stmt),
+ VIEW_CONVERT_EXPR, TREE_TYPE (*lhs_p),
+ *rhs_p);
+ }
+ else if (REFERENCE_CLASS_P (*rhs_p)
+ && is_gimple_reg_type (TREE_TYPE (*lhs_p))
+ && !is_gimple_reg (*lhs_p))
+ /* This can happen when an assignment in between two single field
+ structures is turned into an assignment in between two pointers to
+ scalars (PR 42237). */
+ new_rhs = *rhs_p;
+
+ if (new_rhs)
+ {
+ tree tmp = force_gimple_operand_gsi (gsi, new_rhs, true, NULL_TREE,
+ true, GSI_SAME_STMT);
+
+ gimple_assign_set_rhs_from_tree (gsi, tmp);
+ }
+
+ return true;
+ }
+
+ return false;
+}
+
+/* Traverse the function body and all modifications as described in
+ ADJUSTMENTS. */
+
+static void
+ipa_sra_modify_function_body (ipa_parm_adjustment_vec adjustments)
+{
+ basic_block bb;
+
+ FOR_EACH_BB (bb)
+ {
+ gimple_stmt_iterator gsi;
+ bool bb_changed = false;
+
+ for (gsi = gsi_start_phis (bb); !gsi_end_p (gsi); gsi_next (&gsi))
+ replace_removed_params_ssa_names (gsi_stmt (gsi), adjustments);
+
+ gsi = gsi_start_bb (bb);
+ while (!gsi_end_p (gsi))
+ {
+ gimple stmt = gsi_stmt (gsi);
+ bool modified = false;
+ tree *t;
+ unsigned i;
+
+ switch (gimple_code (stmt))
+ {
+ case GIMPLE_RETURN:
+ t = gimple_return_retval_ptr (stmt);
+ if (*t != NULL_TREE)
+ modified |= sra_ipa_modify_expr (t, true, adjustments);
+ break;
+
+ case GIMPLE_ASSIGN:
+ modified |= sra_ipa_modify_assign (&stmt, &gsi, adjustments);
+ modified |= replace_removed_params_ssa_names (stmt, adjustments);
+ break;
+
+ case GIMPLE_CALL:
+ /* Operands must be processed before the lhs. */
+ for (i = 0; i < gimple_call_num_args (stmt); i++)
+ {
+ t = gimple_call_arg_ptr (stmt, i);
+ modified |= sra_ipa_modify_expr (t, true, adjustments);
+ }
+
+ if (gimple_call_lhs (stmt))
+ {
+ t = gimple_call_lhs_ptr (stmt);
+ modified |= sra_ipa_modify_expr (t, false, adjustments);
+ modified |= replace_removed_params_ssa_names (stmt,
+ adjustments);
+ }
+ break;
+
+ case GIMPLE_ASM:
+ for (i = 0; i < gimple_asm_ninputs (stmt); i++)
+ {
+ t = &TREE_VALUE (gimple_asm_input_op (stmt, i));
+ modified |= sra_ipa_modify_expr (t, true, adjustments);
+ }
+ for (i = 0; i < gimple_asm_noutputs (stmt); i++)
+ {
+ t = &TREE_VALUE (gimple_asm_output_op (stmt, i));
+ modified |= sra_ipa_modify_expr (t, false, adjustments);
+ }
+ break;
+
+ default:
+ break;
+ }
+
+ if (modified)
+ {
+ bb_changed = true;
+ update_stmt (stmt);
+ maybe_clean_eh_stmt (stmt);
+ }
+ gsi_next (&gsi);
+ }
+ if (bb_changed)
+ gimple_purge_dead_eh_edges (bb);
+ }
+}
+
+/* Call gimple_debug_bind_reset_value on all debug statements describing
+ gimple register parameters that are being removed or replaced. */
+
+static void
+sra_ipa_reset_debug_stmts (ipa_parm_adjustment_vec adjustments)
+{
+ int i, len;
+
+ len = VEC_length (ipa_parm_adjustment_t, adjustments);
+ for (i = 0; i < len; i++)
+ {
+ struct ipa_parm_adjustment *adj;
+ imm_use_iterator ui;
+ gimple stmt;
+ tree name;
+
+ adj = VEC_index (ipa_parm_adjustment_t, adjustments, i);
+ if (adj->copy_param || !is_gimple_reg (adj->base))
+ continue;
+ name = gimple_default_def (cfun, adj->base);
+ if (!name)
+ continue;
+ FOR_EACH_IMM_USE_STMT (stmt, ui, name)
+ {
+ /* All other users must have been removed by
+ ipa_sra_modify_function_body. */
+ gcc_assert (is_gimple_debug (stmt));
+ gimple_debug_bind_reset_value (stmt);
+ update_stmt (stmt);
+ }
+ }
+}
+
+/* Return true iff all callers have at least as many actual arguments as there
+ are formal parameters in the current function. */
+
+static bool
+all_callers_have_enough_arguments_p (struct cgraph_node *node)
+{
+ struct cgraph_edge *cs;
+ for (cs = node->callers; cs; cs = cs->next_caller)
+ if (!callsite_has_enough_arguments_p (cs->call_stmt))
+ return false;
+
+ return true;
+}
+
+
+/* Convert all callers of NODE to pass parameters as given in ADJUSTMENTS. */
+
+static void
+convert_callers (struct cgraph_node *node, tree old_decl,
+ ipa_parm_adjustment_vec adjustments)
+{
+ tree old_cur_fndecl = current_function_decl;
+ struct cgraph_edge *cs;
+ basic_block this_block;
+ bitmap recomputed_callers = BITMAP_ALLOC (NULL);
+
+ for (cs = node->callers; cs; cs = cs->next_caller)
+ {
+ current_function_decl = cs->caller->decl;
+ push_cfun (DECL_STRUCT_FUNCTION (cs->caller->decl));
+
+ if (dump_file)
+ fprintf (dump_file, "Adjusting call (%i -> %i) %s -> %s\n",
+ cs->caller->uid, cs->callee->uid,
+ cgraph_node_name (cs->caller),
+ cgraph_node_name (cs->callee));
+
+ ipa_modify_call_arguments (cs, cs->call_stmt, adjustments);
+
+ pop_cfun ();
+ }
+
+ for (cs = node->callers; cs; cs = cs->next_caller)
+ if (!bitmap_bit_p (recomputed_callers, cs->caller->uid))
+ {
+ compute_inline_parameters (cs->caller);
+ bitmap_set_bit (recomputed_callers, cs->caller->uid);
+ }
+ BITMAP_FREE (recomputed_callers);
+
+ current_function_decl = old_cur_fndecl;
+
+ if (!encountered_recursive_call)
+ return;
+
+ FOR_EACH_BB (this_block)
+ {
+ gimple_stmt_iterator gsi;
+
+ for (gsi = gsi_start_bb (this_block); !gsi_end_p (gsi); gsi_next (&gsi))
+ {
+ gimple stmt = gsi_stmt (gsi);
+ tree call_fndecl;
+ if (gimple_code (stmt) != GIMPLE_CALL)
+ continue;
+ call_fndecl = gimple_call_fndecl (stmt);
+ if (call_fndecl == old_decl)
+ {
+ if (dump_file)
+ fprintf (dump_file, "Adjusting recursive call");
+ gimple_call_set_fndecl (stmt, node->decl);
+ ipa_modify_call_arguments (NULL, stmt, adjustments);
+ }
+ }
+ }
+
+ return;
+}
+
+/* Perform all the modification required in IPA-SRA for NODE to have parameters
+ as given in ADJUSTMENTS. */
+
+static void
+modify_function (struct cgraph_node *node, ipa_parm_adjustment_vec adjustments)
+{
+ struct cgraph_node *new_node;
+ struct cgraph_edge *cs;
+ VEC (cgraph_edge_p, heap) * redirect_callers;
+ int node_callers;
+
+ node_callers = 0;
+ for (cs = node->callers; cs != NULL; cs = cs->next_caller)
+ node_callers++;
+ redirect_callers = VEC_alloc (cgraph_edge_p, heap, node_callers);
+ for (cs = node->callers; cs != NULL; cs = cs->next_caller)
+ VEC_quick_push (cgraph_edge_p, redirect_callers, cs);
+
+ rebuild_cgraph_edges ();
+ pop_cfun ();
+ current_function_decl = NULL_TREE;
+
+ new_node = cgraph_function_versioning (node, redirect_callers, NULL, NULL,
+ NULL, NULL, "isra");
+ current_function_decl = new_node->decl;
+ push_cfun (DECL_STRUCT_FUNCTION (new_node->decl));
+
+ ipa_modify_formal_parameters (current_function_decl, adjustments, "ISRA");
+ ipa_sra_modify_function_body (adjustments);
+ sra_ipa_reset_debug_stmts (adjustments);
+ convert_callers (new_node, node->decl, adjustments);
+ cgraph_make_node_local (new_node);
+ return;
+}
+
+/* Return false the function is apparently unsuitable for IPA-SRA based on it's
+ attributes, return true otherwise. NODE is the cgraph node of the current
+ function. */
+
+static bool
+ipa_sra_preliminary_function_checks (struct cgraph_node *node)
+{
+ if (!cgraph_node_can_be_local_p (node))
+ {
+ if (dump_file)
+ fprintf (dump_file, "Function not local to this compilation unit.\n");
+ return false;
+ }
+
+ if (!tree_versionable_function_p (node->decl))
+ {
+ if (dump_file)
+ fprintf (dump_file, "Function not local to this compilation unit.\n");
+ return false;
+ }
+
+ if (DECL_VIRTUAL_P (current_function_decl))
+ {
+ if (dump_file)
+ fprintf (dump_file, "Function is a virtual method.\n");
+ return false;
+ }
+
+ if ((DECL_COMDAT (node->decl) || DECL_EXTERNAL (node->decl))
+ && node->global.size >= MAX_INLINE_INSNS_AUTO)
+ {
+ if (dump_file)
+ fprintf (dump_file, "Function too big to be made truly local.\n");
+ return false;
+ }
+
+ if (!node->callers)
+ {
+ if (dump_file)
+ fprintf (dump_file,
+ "Function has no callers in this compilation unit.\n");
+ return false;
+ }
+
+ if (cfun->stdarg)
+ {
+ if (dump_file)
+ fprintf (dump_file, "Function uses stdarg. \n");
+ return false;
+ }
+
+ if (TYPE_ATTRIBUTES (TREE_TYPE (node->decl)))
+ return false;
+
+ return true;
+}
+
+/* Perform early interprocedural SRA. */
+
+static unsigned int
+ipa_early_sra (void)
+{
+ struct cgraph_node *node = cgraph_node (current_function_decl);
+ ipa_parm_adjustment_vec adjustments;
+ int ret = 0;
+
+ if (!ipa_sra_preliminary_function_checks (node))
+ return 0;
+
+ sra_initialize ();
+ sra_mode = SRA_MODE_EARLY_IPA;
+
+ if (!find_param_candidates ())
+ {
+ if (dump_file)
+ fprintf (dump_file, "Function has no IPA-SRA candidates.\n");
+ goto simple_out;
+ }
+
+ if (!all_callers_have_enough_arguments_p (node))
+ {
+ if (dump_file)
+ fprintf (dump_file, "There are callers with insufficient number of "
+ "arguments.\n");
+ goto simple_out;
+ }
+
+ bb_dereferences = XCNEWVEC (HOST_WIDE_INT,
+ func_param_count
+ * last_basic_block_for_function (cfun));
+ final_bbs = BITMAP_ALLOC (NULL);
+
+ scan_function ();
+ if (encountered_apply_args)
+ {
+ if (dump_file)
+ fprintf (dump_file, "Function calls __builtin_apply_args().\n");
+ goto out;
+ }
+
+ if (encountered_unchangable_recursive_call)
+ {
+ if (dump_file)
+ fprintf (dump_file, "Function calls itself with insufficient "
+ "number of arguments.\n");
+ goto out;
+ }
+
+ adjustments = analyze_all_param_acesses ();
+ if (!adjustments)
+ goto out;
+ if (dump_file)
+ ipa_dump_param_adjustments (dump_file, adjustments, current_function_decl);
+
+ modify_function (node, adjustments);
+ VEC_free (ipa_parm_adjustment_t, heap, adjustments);
+ ret = TODO_update_ssa;
+
+ statistics_counter_event (cfun, "Unused parameters deleted",
+ sra_stats.deleted_unused_parameters);
+ statistics_counter_event (cfun, "Scalar parameters converted to by-value",
+ sra_stats.scalar_by_ref_to_by_val);
+ statistics_counter_event (cfun, "Aggregate parameters broken up",
+ sra_stats.aggregate_params_reduced);
+ statistics_counter_event (cfun, "Aggregate parameter components created",
+ sra_stats.param_reductions_created);
+
+ out:
+ BITMAP_FREE (final_bbs);
+ free (bb_dereferences);
+ simple_out:
+ sra_deinitialize ();
+ return ret;
+}
+
+/* Return if early ipa sra shall be performed. */
+static bool
+ipa_early_sra_gate (void)
+{
+ return flag_ipa_sra;
+}
+
+struct gimple_opt_pass pass_early_ipa_sra =
+{
+ {
+ GIMPLE_PASS,
+ "eipa_sra", /* name */
+ ipa_early_sra_gate, /* gate */
+ ipa_early_sra, /* execute */
+ NULL, /* sub */
+ NULL, /* next */
+ 0, /* static_pass_number */
+ TV_IPA_SRA, /* tv_id */
+ 0, /* properties_required */
+ 0, /* properties_provided */
+ 0, /* properties_destroyed */
+ 0, /* todo_flags_start */
+ TODO_dump_func | TODO_dump_cgraph /* todo_flags_finish */
+ }
+};
+
+