/* Scalar Replacement of Aggregates (SRA) converts some structure
references into scalar references, exposing them to the scalar
optimizers.
- Copyright (C) 2003, 2004 Free Software Foundation, Inc.
+ Copyright (C) 2003, 2004, 2005 Free Software Foundation, Inc.
Contributed by Diego Novillo <dnovillo@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 2, or (at your option) any
later version.
-
+
GCC is distributed in the hope that it will be useful, but WITHOUT
ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
for more details.
-
+
You should have received a copy of the GNU General Public License
along with GCC; see the file COPYING. If not, write to the Free
-Software Foundation, 59 Temple Place - Suite 330, Boston, MA
-02111-1307, USA. */
+Software Foundation, 51 Franklin Street, Fifth Floor, Boston, MA
+02110-1301, USA. */
#include "config.h"
#include "system.h"
#include "coretypes.h"
#include "tm.h"
-#include "errors.h"
#include "ggc.h"
#include "tree.h"
#include "bitmap.h"
#include "obstack.h"
#include "target.h"
+/* expr.h is needed for MOVE_RATIO. */
+#include "expr.h"
+#include "params.h"
/* This object of this pass is to replace a non-addressable aggregate with a
set of independent variables. Most of the time, all of these variables
- will be scalars. But a secondary objective is to break up larger
+ will be scalars. But a secondary objective is to break up larger
aggregates into smaller aggregates. In the process we may find that some
bits of the larger aggregate can be deleted as unreferenced.
};
/* Random access to the child of a parent is performed by hashing.
- This prevents quadratic behaviour, and allows SRA to function
+ This prevents quadratic behavior, and allows SRA to function
reasonably on larger records. */
static htab_t sra_map;
static void dump_sra_elt_name (FILE *, struct sra_elt *);
extern void debug_sra_elt_name (struct sra_elt *);
+/* Forward declarations. */
+static tree generate_element_ref (struct sra_elt *);
\f
/* Return true if DECL is an SRA candidate. */
static bool
is_sra_candidate_decl (tree decl)
{
- return DECL_P (decl) && bitmap_bit_p (sra_candidates, var_ann (decl)->uid);
+ return DECL_P (decl) && bitmap_bit_p (sra_candidates, DECL_UID (decl));
}
/* Return true if TYPE is a scalar type. */
instantiated, just that if we decide to break up the type into
separate pieces that it can be done. */
-static bool
-type_can_be_decomposed_p (tree type)
+bool
+sra_type_can_be_decomposed_p (tree type)
{
unsigned int cache = TYPE_UID (TYPE_MAIN_VARIANT (type)) * 2;
tree t;
if (bitmap_bit_p (sra_type_decomp_cache, cache+1))
return false;
- /* The type must have a definite non-zero size. */
- if (TYPE_SIZE (type) == NULL || integer_zerop (TYPE_SIZE (type)))
+ /* The type must have a definite nonzero size. */
+ if (TYPE_SIZE (type) == NULL || TREE_CODE (TYPE_SIZE (type)) != INTEGER_CST
+ || integer_zerop (TYPE_SIZE (type)))
goto fail;
/* The type must be a non-union aggregate. */
}
/* We must be able to decompose the variable's type. */
- if (!type_can_be_decomposed_p (TREE_TYPE (var)))
+ if (!sra_type_can_be_decomposed_p (TREE_TYPE (var)))
{
if (dump_file && (dump_flags & TDF_DETAILS))
{
{
if (is_sra_scalar_type (type))
return true;
- if (!type_can_be_decomposed_p (type))
+ if (!sra_type_can_be_decomposed_p (type))
return false;
switch (TREE_CODE (type))
return true;
default:
- abort ();
+ gcc_unreachable ();
}
}
static hashval_t
sra_hash_tree (tree t)
{
+ hashval_t h;
+
switch (TREE_CODE (t))
{
case VAR_DECL:
case PARM_DECL:
case RESULT_DECL:
- case FIELD_DECL:
- return DECL_UID (t);
+ h = DECL_UID (t);
+ break;
+
case INTEGER_CST:
- return TREE_INT_CST_LOW (t) ^ TREE_INT_CST_HIGH (t);
+ h = TREE_INT_CST_LOW (t) ^ TREE_INT_CST_HIGH (t);
+ break;
+
+ case FIELD_DECL:
+ /* We can have types that are compatible, but have different member
+ lists, so we can't hash fields by ID. Use offsets instead. */
+ h = iterative_hash_expr (DECL_FIELD_OFFSET (t), 0);
+ h = iterative_hash_expr (DECL_FIELD_BIT_OFFSET (t), h);
+ break;
+
default:
- abort ();
+ gcc_unreachable ();
}
+
+ return h;
}
/* Hash function for type SRA_PAIR. */
/* Take into account everything back up the chain. Given that chain
lengths are rarely very long, this should be acceptable. If we
- truely identify this as a performance problem, it should work to
+ truly identify this as a performance problem, it should work to
hash the pointer value "e->parent". */
for (p = e->parent; p ; p = p->parent)
h = (h * 65521) ^ sra_hash_tree (p->element);
return h;
}
-
+
/* Equality function for type SRA_PAIR. */
static int
{
const struct sra_elt *a = x;
const struct sra_elt *b = y;
+ tree ae, be;
if (a->parent != b->parent)
return false;
- /* All the field/decl stuff is unique. */
- if (a->element == b->element)
- return true;
+ ae = a->element;
+ be = b->element;
- /* The only thing left is integer equality. */
- if (TREE_CODE (a->element) == INTEGER_CST
- && TREE_CODE (b->element) == INTEGER_CST)
- return tree_int_cst_equal (a->element, b->element);
- else
+ if (ae == be)
+ return true;
+ if (TREE_CODE (ae) != TREE_CODE (be))
return false;
+
+ switch (TREE_CODE (ae))
+ {
+ case VAR_DECL:
+ case PARM_DECL:
+ case RESULT_DECL:
+ /* These are all pointer unique. */
+ return false;
+
+ case INTEGER_CST:
+ /* Integers are not pointer unique, so compare their values. */
+ return tree_int_cst_equal (ae, be);
+
+ case FIELD_DECL:
+ /* Fields are unique within a record, but not between
+ compatible records. */
+ if (DECL_FIELD_CONTEXT (ae) == DECL_FIELD_CONTEXT (be))
+ return false;
+ return fields_compatible_p (ae, be);
+
+ default:
+ gcc_unreachable ();
+ }
}
/* Create or return the SRA_ELT structure for CHILD in PARENT. PARENT
if (TREE_CODE (child) == PARM_DECL)
{
elt->n_copies = 1;
- bitmap_set_bit (needs_copy_in, var_ann (child)->uid);
+ bitmap_set_bit (needs_copy_in, DECL_UID (child));
}
}
return true;
}
-/* Create or return the SRA_ELT structure for EXPR if the expression
+/* Create or return the SRA_ELT structure for EXPR if the expression
refers to a scalarizable variable. */
static struct sra_elt *
};
#ifdef ENABLE_CHECKING
-/* Invoked via walk_tree, if *TP contains an candidate decl, return it. */
+/* Invoked via walk_tree, if *TP contains a candidate decl, return it. */
static tree
sra_find_candidate_decl (tree *tp, int *walk_subtrees,
{
tree expr = *expr_p;
tree inner = expr;
+ bool disable_scalarization = false;
/* We're looking to collect a reference expression between EXPR and INNER,
such that INNER is a scalarizable decl and all other nodes through EXPR
if (is_sra_candidate_decl (inner))
{
struct sra_elt *elt = maybe_lookup_element_for_expr (expr);
- fns->use (elt, expr_p, bsi, is_output);
+ if (disable_scalarization)
+ elt->cannot_scalarize = true;
+ else
+ fns->use (elt, expr_p, bsi, is_output);
}
return;
index reference inside a loop being overridden by several constant
index references during loop setup. It's possible that this could
be avoided by using dynamic usage counts based on BB trip counts
- (based on loop analysis or profiling), but that hardly seems worth
+ (based on loop analysis or profiling), but that hardly seems worth
the effort. */
/* ??? Hack. Figure out how to push this into the scan routines
without duplicating too much code. */
if (!is_valid_const_index (inner))
{
- if (fns->initial_scan)
- {
- struct sra_elt *elt
- = maybe_lookup_element_for_expr (TREE_OPERAND (inner, 0));
- if (elt)
- elt->cannot_scalarize = true;
- }
- return;
+ disable_scalarization = true;
+ goto use_all;
}
/* ??? Are we assured that non-constant bounds and stride will have
the same value everywhere? I don't think Fortran will... */
case BIT_FIELD_REF:
/* A bit field reference (access to *multiple* fields simultaneously)
- is not currently scalarized. Consider this an access to the
+ is not currently scalarized. Consider this an access to the
complete outer element, to which walk_tree will bring us next. */
goto use_all;
case ARRAY_RANGE_REF:
- /* Similarly, an subrange reference is used to modify indexing. Which
+ /* Similarly, a subrange reference is used to modify indexing. Which
means that the canonical element names that we have won't work. */
goto use_all;
type other than the one we've scalarized. */
goto use_all;
+ case WITH_SIZE_EXPR:
+ /* This is a transparent wrapper. The entire inner expression really
+ is being used. */
+ goto use_all;
+
use_all:
expr_p = &TREE_OPERAND (inner, 0);
inner = expr = *expr_p;
default:
#ifdef ENABLE_CHECKING
/* Validate that we're not missing any references. */
- if (walk_tree (&inner, sra_find_candidate_decl, NULL, NULL))
- abort ();
+ gcc_assert (!walk_tree (&inner, sra_find_candidate_decl, NULL, NULL));
#endif
return;
}
return;
}
+ /* If the RHS is scalarizable, handle it. There are only two cases. */
+ if (rhs_elt)
+ {
+ if (!rhs_elt->is_scalar)
+ fns->ldst (rhs_elt, lhs, bsi, false);
+ else
+ fns->use (rhs_elt, &TREE_OPERAND (expr, 1), bsi, false);
+ }
+
+ /* If it isn't scalarizable, there may be scalarizable variables within, so
+ check for a call or else walk the RHS to see if we need to do any
+ copy-in operations. We need to do it before the LHS is scalarized so
+ that the statements get inserted in the proper place, before any
+ copy-out operations. */
+ else
+ {
+ tree call = get_call_expr_in (rhs);
+ if (call)
+ sra_walk_call_expr (call, bsi, fns);
+ else
+ sra_walk_expr (&TREE_OPERAND (expr, 1), bsi, false, fns);
+ }
+
+ /* Likewise, handle the LHS being scalarizable. We have cases similar
+ to those above, but also want to handle RHS being constant. */
if (lhs_elt)
{
/* If this is an assignment from a constant, or constructor, then
&& TREE_STATIC (rhs)
&& TREE_READONLY (rhs)
&& targetm.binds_local_p (rhs))
- {
- if (DECL_INITIAL (rhs) != error_mark_node)
- fns->init (lhs_elt, DECL_INITIAL (rhs), bsi);
- }
+ fns->init (lhs_elt, DECL_INITIAL (rhs), bsi);
/* If this is a copy from a non-scalarizable lvalue, invoke LDST.
The lvalue requirement prevents us from trying to directly scalarize
the result of a function call. Which would result in trying to call
the function multiple times, and other evil things. */
- else if (!lhs_elt->is_scalar && is_gimple_addr_expr_arg (rhs))
+ else if (!lhs_elt->is_scalar && is_gimple_addressable (rhs))
fns->ldst (lhs_elt, rhs, bsi, true);
-
+
/* Otherwise we're being used in some context that requires the
aggregate to be seen as a whole. Invoke USE. */
else
fns->use (lhs_elt, &TREE_OPERAND (expr, 0), bsi, true);
}
- else
- {
- /* LHS_ELT being null only means that the LHS as a whole is not a
- scalarizable reference. There may be occurrences of scalarizable
- variables within, which implies a USE. */
- sra_walk_expr (&TREE_OPERAND (expr, 0), bsi, true, fns);
- }
- /* Likewise for the right-hand side. The only difference here is that
- we don't have to handle constants, and the RHS may be a call. */
- if (rhs_elt)
- {
- if (!rhs_elt->is_scalar)
- fns->ldst (rhs_elt, lhs, bsi, false);
- else
- fns->use (rhs_elt, &TREE_OPERAND (expr, 1), bsi, false);
- }
- else if (TREE_CODE (rhs) == CALL_EXPR)
- sra_walk_call_expr (rhs, bsi, fns);
+ /* Similarly to above, LHS_ELT being null only means that the LHS as a
+ whole is not a scalarizable reference. There may be occurrences of
+ scalarizable variables within, which implies a USE. */
else
- sra_walk_expr (&TREE_OPERAND (expr, 1), bsi, false, fns);
+ sra_walk_expr (&TREE_OPERAND (expr, 0), bsi, true, fns);
}
/* Entry point to the walk functions. Search the entire function,
sra_walk_function (const struct sra_walk_fns *fns)
{
basic_block bb;
- block_stmt_iterator si;
+ block_stmt_iterator si, ni;
/* ??? Phase 4 could derive some benefit to walking the function in
dominator tree order. */
FOR_EACH_BB (bb)
- for (si = bsi_start (bb); !bsi_end_p (si); bsi_next (&si))
+ for (si = bsi_start (bb); !bsi_end_p (si); si = ni)
{
tree stmt, t;
stmt_ann_t ann;
stmt = bsi_stmt (si);
ann = stmt_ann (stmt);
+ ni = si;
+ bsi_next (&ni);
+
/* If the statement has no virtual operands, then it doesn't
make any structure references that we care about. */
- if (NUM_V_MAY_DEFS (V_MAY_DEF_OPS (ann)) == 0
- && NUM_VUSES (VUSE_OPS (ann)) == 0
- && NUM_V_MUST_DEFS (V_MUST_DEF_OPS (ann)) == 0)
+ if (ZERO_SSA_OPERANDS (stmt, (SSA_OP_VIRTUAL_DEFS | SSA_OP_VUSE)))
continue;
switch (TREE_CODE (stmt))
static bool
find_candidates_for_sra (void)
{
- size_t i;
bool any_set = false;
+ tree var;
+ referenced_var_iterator rvi;
- for (i = 0; i < num_referenced_vars; i++)
+ FOR_EACH_REFERENCED_VAR (var, rvi)
{
- tree var = referenced_var (i);
if (decl_can_be_decomposed_p (var))
{
- bitmap_set_bit (sra_candidates, var_ann (var)->uid);
+ bitmap_set_bit (sra_candidates, DECL_UID (var));
any_set = true;
}
}
-
+
return any_set;
}
static const struct sra_walk_fns fns = {
scan_use, scan_copy, scan_init, scan_ldst, true
};
+ bitmap_iterator bi;
sra_walk_function (&fns);
if (dump_file && (dump_flags & TDF_DETAILS))
{
- size_t i;
+ unsigned i;
fputs ("\nScan results:\n", dump_file);
- EXECUTE_IF_SET_IN_BITMAP (sra_candidates, 0, i,
+ EXECUTE_IF_SET_IN_BITMAP (sra_candidates, 0, i, bi)
{
tree var = referenced_var (i);
struct sra_elt *elt = lookup_element (NULL, var, NULL, NO_INSERT);
if (elt)
scan_dump (elt);
- });
+ }
fputc ('\n', dump_file);
}
}
{
build_element_name_1 (elt);
obstack_1grow (&sra_obstack, '\0');
- return obstack_finish (&sra_obstack);
+ return XOBFINISH (&sra_obstack, char *);
}
/* Instantiate an element as an independent variable. */
elt->replacement = var = make_rename_temp (elt->type, "SR");
DECL_SOURCE_LOCATION (var) = DECL_SOURCE_LOCATION (base);
- TREE_NO_WARNING (var) = TREE_NO_WARNING (base);
- DECL_ARTIFICIAL (var) = DECL_ARTIFICIAL (base);
+ DECL_ARTIFICIAL (var) = 1;
+
+ if (TREE_THIS_VOLATILE (elt->type))
+ {
+ TREE_THIS_VOLATILE (var) = 1;
+ TREE_SIDE_EFFECTS (var) = 1;
+ }
if (DECL_NAME (base) && !DECL_IGNORED_P (base))
{
char *pretty_name = build_element_name (elt);
DECL_NAME (var) = get_identifier (pretty_name);
obstack_free (&sra_obstack, pretty_name);
+
+ SET_DECL_DEBUG_EXPR (var, generate_element_ref (elt));
+ DECL_DEBUG_EXPR_IS_FROM (var) = 1;
+
+ DECL_IGNORED_P (var) = 0;
+ TREE_NO_WARNING (var) = TREE_NO_WARNING (base);
+ }
+ else
+ {
+ DECL_IGNORED_P (var) = 1;
+ /* ??? We can't generate any warning that would be meaningful. */
+ TREE_NO_WARNING (var) = 1;
}
if (dump_file)
break;
default:
- abort ();
+ gcc_unreachable ();
}
}
fputc ('\n', dump_file);
}
+ /* Disable scalarization of sub-elements */
+ for (c = elt->children; c; c = c->sibling)
+ {
+ c->cannot_scalarize = 1;
+ decide_block_copy (c);
+ }
return false;
}
tree size_tree = TYPE_SIZE_UNIT (elt->type);
bool use_block_copy = true;
+ /* Tradeoffs for COMPLEX types pretty much always make it better
+ to go ahead and split the components. */
+ if (TREE_CODE (elt->type) == COMPLEX_TYPE)
+ use_block_copy = false;
+
/* Don't bother trying to figure out the rest if the structure is
so large we can't do easy arithmetic. This also forces block
copies for variable sized structures. */
- if (host_integerp (size_tree, 1))
+ else if (host_integerp (size_tree, 1))
{
unsigned HOST_WIDE_INT full_size, inst_size = 0;
- unsigned int inst_count;
+ unsigned int max_size, max_count, inst_count, full_count;
+
+ /* If the sra-max-structure-size parameter is 0, then the
+ user has not overridden the parameter and we can choose a
+ sensible default. */
+ max_size = SRA_MAX_STRUCTURE_SIZE
+ ? SRA_MAX_STRUCTURE_SIZE
+ : MOVE_RATIO * UNITS_PER_WORD;
+ max_count = SRA_MAX_STRUCTURE_COUNT
+ ? SRA_MAX_STRUCTURE_COUNT
+ : MOVE_RATIO;
full_size = tree_low_cst (size_tree, 1);
+ full_count = count_type_elements (elt->type, false);
+ inst_count = sum_instantiated_sizes (elt, &inst_size);
- /* ??? What to do here. If there are two fields, and we've only
+ /* ??? What to do here. If there are two fields, and we've only
instantiated one, then instantiating the other is clearly a win.
If there are a large number of fields then the size of the copy
is much more of a factor. */
/* If the structure is small, and we've made copies, go ahead
and instantiate, hoping that the copies will go away. */
- if (full_size <= (unsigned) MOVE_RATIO * UNITS_PER_WORD
+ if (full_size <= max_size
+ && (full_count - inst_count) <= max_count
&& elt->n_copies > elt->n_uses)
use_block_copy = false;
- else
- {
- inst_count = sum_instantiated_sizes (elt, &inst_size);
-
- if (inst_size * 4 >= full_size * 3)
- use_block_copy = false;
- }
+ else if (inst_count * 100 >= full_count * SRA_FIELD_STRUCTURE_RATIO
+ && inst_size * 100 >= full_size * SRA_FIELD_STRUCTURE_RATIO)
+ use_block_copy = false;
/* In order to avoid block copy, we have to be able to instantiate
all elements of the type. See if this is possible. */
{
unsigned int i;
bool cleared_any;
- struct bitmap_head_def done_head;
+ bitmap_head done_head;
+ bitmap_iterator bi;
/* We cannot clear bits from a bitmap we're iterating over,
so save up all the bits to clear until the end. */
- bitmap_initialize (&done_head, 1);
+ bitmap_initialize (&done_head, &bitmap_default_obstack);
cleared_any = false;
- EXECUTE_IF_SET_IN_BITMAP (sra_candidates, 0, i,
+ EXECUTE_IF_SET_IN_BITMAP (sra_candidates, 0, i, bi)
{
tree var = referenced_var (i);
struct sra_elt *elt = lookup_element (NULL, var, NULL, NO_INSERT);
bitmap_set_bit (&done_head, i);
cleared_any = true;
}
- });
+ }
if (cleared_any)
{
- bitmap_operation (sra_candidates, sra_candidates, &done_head,
- BITMAP_AND_COMPL);
- bitmap_operation (needs_copy_in, needs_copy_in, &done_head,
- BITMAP_AND_COMPL);
+ bitmap_and_compl_into (sra_candidates, &done_head);
+ bitmap_and_compl_into (needs_copy_in, &done_head);
}
bitmap_clear (&done_head);
+ mark_set_for_renaming (sra_candidates);
+
if (dump_file)
fputc ('\n', dump_file);
}
renaming. This becomes necessary when we modify all of a non-scalar. */
static void
-mark_all_v_defs (tree stmt)
+mark_all_v_defs_1 (tree stmt)
{
- v_may_def_optype v_may_defs;
- v_must_def_optype v_must_defs;
- size_t i, n;
+ tree sym;
+ ssa_op_iter iter;
- get_stmt_operands (stmt);
+ update_stmt_if_modified (stmt);
- v_may_defs = V_MAY_DEF_OPS (stmt_ann (stmt));
- n = NUM_V_MAY_DEFS (v_may_defs);
- for (i = 0; i < n; i++)
+ FOR_EACH_SSA_TREE_OPERAND (sym, stmt, iter, SSA_OP_ALL_VIRTUALS)
{
- tree sym = V_MAY_DEF_RESULT (v_may_defs, i);
if (TREE_CODE (sym) == SSA_NAME)
sym = SSA_NAME_VAR (sym);
- bitmap_set_bit (vars_to_rename, var_ann (sym)->uid);
+ mark_sym_for_renaming (sym);
}
+}
+
- v_must_defs = V_MUST_DEF_OPS (stmt_ann (stmt));
- n = NUM_V_MUST_DEFS (v_must_defs);
- for (i = 0; i < n; i++)
+/* Mark all the variables in virtual operands in all the statements in
+ LIST for renaming. */
+
+static void
+mark_all_v_defs (tree list)
+{
+ if (TREE_CODE (list) != STATEMENT_LIST)
+ mark_all_v_defs_1 (list);
+ else
{
- tree sym = V_MUST_DEF_OP (v_must_defs, i);
- if (TREE_CODE (sym) == SSA_NAME)
- sym = SSA_NAME_VAR (sym);
- bitmap_set_bit (vars_to_rename, var_ann (sym)->uid);
+ tree_stmt_iterator i;
+ for (i = tsi_start (list); !tsi_end_p (i); tsi_next (&i))
+ mark_all_v_defs_1 (tsi_stmt (i));
}
}
+
/* Build a single level component reference to ELT rooted at BASE. */
static tree
switch (TREE_CODE (TREE_TYPE (base)))
{
case RECORD_TYPE:
- return build (COMPONENT_REF, elt->type, base, elt->element, NULL);
+ {
+ tree field = elt->element;
+
+ /* Watch out for compatible records with differing field lists. */
+ if (DECL_FIELD_CONTEXT (field) != TYPE_MAIN_VARIANT (TREE_TYPE (base)))
+ field = find_compatible_field (TREE_TYPE (base), field);
+
+ return build (COMPONENT_REF, elt->type, base, field, NULL);
+ }
case ARRAY_TYPE:
return build (ARRAY_REF, elt->type, base, elt->element, NULL, NULL);
return build (IMAGPART_EXPR, elt->type, base);
default:
- abort ();
+ gcc_unreachable ();
}
}
struct sra_elt *c;
tree t;
- if (elt->replacement)
+ if (!copy_out && TREE_CODE (expr) == SSA_NAME
+ && TREE_CODE (TREE_TYPE (expr)) == COMPLEX_TYPE)
+ {
+ tree r, i;
+
+ c = lookup_element (elt, integer_zero_node, NULL, NO_INSERT);
+ r = c->replacement;
+ c = lookup_element (elt, integer_one_node, NULL, NO_INSERT);
+ i = c->replacement;
+
+ t = build (COMPLEX_EXPR, elt->type, r, i);
+ t = build (MODIFY_EXPR, void_type_node, expr, t);
+ SSA_NAME_DEF_STMT (expr) = t;
+ append_to_statement_list (t, list_p);
+ }
+ else if (elt->replacement)
{
if (copy_out)
t = build (MODIFY_EXPR, void_type_node, elt->replacement, expr);
for (dc = dst->children; dc ; dc = dc->sibling)
{
sc = lookup_element (src, dc->element, NULL, NO_INSERT);
- if (sc == NULL)
- abort ();
+ gcc_assert (sc);
generate_element_copy (dc, sc, list_p);
}
{
tree t;
- if (src->replacement == NULL)
- abort ();
+ gcc_assert (src->replacement);
t = build (MODIFY_EXPR, void_type_node, dst->replacement,
src->replacement);
{
struct sra_elt *c;
+ if (elt->visited)
+ {
+ elt->visited = false;
+ return;
+ }
+
for (c = elt->children; c ; c = c->sibling)
generate_element_zero (c, list_p);
- if (elt->visited)
- elt->visited = false;
- else if (elt->replacement)
+ if (elt->replacement)
{
tree t;
- if (elt->is_scalar)
- t = fold_convert (elt->type, integer_zero_node);
- else
- /* We generated a replacement for a non-scalar? */
- abort ();
+ gcc_assert (elt->is_scalar);
+ t = fold_convert (elt->type, integer_zero_node);
t = build (MODIFY_EXPR, void_type_node, elt->replacement, t);
append_to_statement_list (t, list_p);
}
}
+/* Generate an assignment VAR = INIT, where INIT may need gimplification.
+ Add the result to *LIST_P. */
+
+static void
+generate_one_element_init (tree var, tree init, tree *list_p)
+{
+ /* The replacement can be almost arbitrarily complex. Gimplify. */
+ tree stmt = build (MODIFY_EXPR, void_type_node, var, init);
+ gimplify_and_add (stmt, list_p);
+}
+
/* Generate a set of assignment statements in *LIST_P to set all instantiated
elements under ELT with the contents of the initializer INIT. In addition,
mark all assigned elements VISITED; this allows easy coordination with
- generate_element_zero. */
+ generate_element_zero. Return false if we found a case we couldn't
+ handle. */
-static void
-generate_element_init (struct sra_elt *elt, tree init, tree *list_p)
+static bool
+generate_element_init_1 (struct sra_elt *elt, tree init, tree *list_p)
{
- enum tree_code init_code = TREE_CODE (init);
+ bool result = true;
+ enum tree_code init_code;
struct sra_elt *sub;
tree t;
+ unsigned HOST_WIDE_INT idx;
+ tree value, purpose;
+
+ /* We can be passed DECL_INITIAL of a static variable. It might have a
+ conversion, which we strip off here. */
+ STRIP_USELESS_TYPE_CONVERSION (init);
+ init_code = TREE_CODE (init);
if (elt->is_scalar)
{
if (elt->replacement)
{
- t = build (MODIFY_EXPR, void_type_node, elt->replacement, init);
- append_to_statement_list (t, list_p);
+ generate_one_element_init (elt->replacement, init, list_p);
elt->visited = true;
}
- return;
+ return result;
}
switch (init_code)
else
t = (init_code == COMPLEX_EXPR
? TREE_OPERAND (init, 1) : TREE_IMAGPART (init));
- generate_element_init (sub, t, list_p);
+ result &= generate_element_init_1 (sub, t, list_p);
}
break;
case CONSTRUCTOR:
- for (t = CONSTRUCTOR_ELTS (init); t ; t = TREE_CHAIN (t))
+ FOR_EACH_CONSTRUCTOR_ELT (CONSTRUCTOR_ELTS (init), idx, purpose, value)
{
- sub = lookup_element (elt, TREE_PURPOSE (t), NULL, NO_INSERT);
- if (sub == NULL)
- continue;
- generate_element_init (sub, TREE_VALUE (t), list_p);
+ if (TREE_CODE (purpose) == RANGE_EXPR)
+ {
+ tree lower = TREE_OPERAND (purpose, 0);
+ tree upper = TREE_OPERAND (purpose, 1);
+
+ while (1)
+ {
+ sub = lookup_element (elt, lower, NULL, NO_INSERT);
+ if (sub != NULL)
+ result &= generate_element_init_1 (sub, value, list_p);
+ if (tree_int_cst_equal (lower, upper))
+ break;
+ lower = int_const_binop (PLUS_EXPR, lower,
+ integer_one_node, true);
+ }
+ }
+ else
+ {
+ sub = lookup_element (elt, purpose, NULL, NO_INSERT);
+ if (sub != NULL)
+ result &= generate_element_init_1 (sub, value, list_p);
+ }
}
break;
default:
- abort ();
+ elt->visited = true;
+ result = false;
+ }
+
+ return result;
+}
+
+/* A wrapper function for generate_element_init_1 that handles cleanup after
+ gimplification. */
+
+static bool
+generate_element_init (struct sra_elt *elt, tree init, tree *list_p)
+{
+ bool ret;
+
+ push_gimplify_context ();
+ ret = generate_element_init_1 (elt, init, list_p);
+ pop_gimplify_context (NULL);
+
+ /* The replacement can expose previously unreferenced variables. */
+ if (ret && *list_p)
+ {
+ tree_stmt_iterator i;
+
+ for (i = tsi_start (*list_p); !tsi_end_p (i); tsi_next (&i))
+ find_new_referenced_vars (tsi_stmt_ptr (i));
}
+
+ return ret;
}
/* Insert STMT on all the outgoing edges out of BB. Note that if BB
insert_edge_copies (tree stmt, basic_block bb)
{
edge e;
+ edge_iterator ei;
bool first_copy;
first_copy = true;
- for (e = bb->succ; e; e = e->succ_next)
+ FOR_EACH_EDGE (e, ei, bb->succs)
{
/* We don't need to insert copies on abnormal edges. The
value of the scalar replacement is not guaranteed to
first_copy = false;
}
else
- bsi_insert_on_edge (e, lhd_unsave_expr_now (stmt));
+ bsi_insert_on_edge (e, unsave_expr_now (stmt));
}
}
}
/* Helper function to insert LIST before BSI, and set up line number info. */
-static void
+void
sra_insert_before (block_stmt_iterator *bsi, tree list)
{
tree stmt = bsi_stmt (*bsi);
/* Similarly, but insert after BSI. Handles insertion onto edges as well. */
-static void
+void
sra_insert_after (block_stmt_iterator *bsi, tree list)
{
tree stmt = bsi_stmt (*bsi);
if (stmt_ends_bb_p (stmt))
insert_edge_copies (list, bsi->bb);
else
- bsi_insert_after (bsi, list, BSI_CONTINUE_LINKING);
+ bsi_insert_after (bsi, list, BSI_SAME_STMT);
}
/* Similarly, but replace the statement at BSI. */
}
/* Scalarize a USE. To recap, this is either a simple reference to ELT,
- if elt is scalar, or some ocurrence of ELT that requires a complete
+ if elt is scalar, or some occurrence of ELT that requires a complete
aggregate. IS_OUTPUT is true if ELT is being modified. */
static void
if (is_output)
mark_all_v_defs (stmt);
*expr_p = elt->replacement;
- modify_stmt (stmt);
+ update_stmt (stmt);
}
else
{
generate_copy_inout (elt, is_output, generate_element_ref (elt), &list);
if (list == NULL)
return;
+ mark_all_v_defs (list);
if (is_output)
- {
- mark_all_v_defs (expr_first (list));
- sra_insert_after (bsi, list);
- }
+ sra_insert_after (bsi, list);
else
sra_insert_before (bsi, list);
}
/* If we have two scalar operands, modify the existing statement. */
stmt = bsi_stmt (*bsi);
-#ifdef ENABLE_CHECKING
/* See the commentary in sra_walk_function concerning
RETURN_EXPR, and why we should never see one here. */
- if (TREE_CODE (stmt) != MODIFY_EXPR)
- abort ();
-#endif
+ gcc_assert (TREE_CODE (stmt) == MODIFY_EXPR);
TREE_OPERAND (stmt, 0) = lhs_elt->replacement;
TREE_OPERAND (stmt, 1) = rhs_elt->replacement;
- modify_stmt (stmt);
+ update_stmt (stmt);
}
else if (lhs_elt->use_block_copy || rhs_elt->use_block_copy)
{
/* If either side requires a block copy, then sync the RHS back
- to the original structure, leave the original assignment
+ to the original structure, leave the original assignment
statement (which will perform the block copy), then load the
LHS values out of its now-updated original structure. */
/* ??? Could perform a modified pair-wise element copy. That
generate_element_ref (rhs_elt), &list);
if (list)
{
- mark_all_v_defs (expr_first (list));
+ mark_all_v_defs (list);
sra_insert_before (bsi, list);
}
generate_copy_inout (lhs_elt, true,
generate_element_ref (lhs_elt), &list);
if (list)
- sra_insert_after (bsi, list);
+ {
+ mark_all_v_defs (list);
+ sra_insert_after (bsi, list);
+ }
}
else
{
list = NULL;
generate_element_copy (lhs_elt, rhs_elt, &list);
- if (list == NULL)
- abort ();
+ gcc_assert (list);
+ mark_all_v_defs (list);
sra_replace (bsi, list);
}
}
static void
scalarize_init (struct sra_elt *lhs_elt, tree rhs, block_stmt_iterator *bsi)
{
+ bool result = true;
tree list = NULL;
/* Generate initialization statements for all members extant in the RHS. */
if (rhs)
- generate_element_init (lhs_elt, rhs, &list);
+ {
+ /* Unshare the expression just in case this is from a decl's initial. */
+ rhs = unshare_expr (rhs);
+ result = generate_element_init (lhs_elt, rhs, &list);
+ }
/* CONSTRUCTOR is defined such that any member not mentioned is assigned
a zero value. Initialize the rest of the instantiated elements. */
generate_element_zero (lhs_elt, &list);
- if (list == NULL)
- return;
- if (lhs_elt->use_block_copy)
+ if (!result)
+ {
+ /* If we failed to convert the entire initializer, then we must
+ leave the structure assignment in place and must load values
+ from the structure into the slots for which we did not find
+ constants. The easiest way to do this is to generate a complete
+ copy-out, and then follow that with the constant assignments
+ that we were able to build. DCE will clean things up. */
+ tree list0 = NULL;
+ generate_copy_inout (lhs_elt, true, generate_element_ref (lhs_elt),
+ &list0);
+ append_to_statement_list (list, &list0);
+ list = list0;
+ }
+
+ if (lhs_elt->use_block_copy || !result)
{
/* Since LHS is not fully instantiated, we must leave the structure
assignment in place. Treating this case differently from a USE
exposes constants to later optimizations. */
- mark_all_v_defs (expr_first (list));
- sra_insert_after (bsi, list);
+ if (list)
+ {
+ mark_all_v_defs (list);
+ sra_insert_after (bsi, list);
+ }
}
else
{
/* The LHS is fully instantiated. The list of initializations
replaces the original structure assignment. */
+ gcc_assert (list);
mark_all_v_defs (bsi_stmt (*bsi));
+ mark_all_v_defs (list);
sra_replace (bsi, list);
}
}
TREE_THIS_NOTRAP (t) = 1;
*walk_subtrees = 0;
}
- else if (DECL_P (t) || TYPE_P (t))
+ else if (IS_TYPE_OR_DECL_P (t))
*walk_subtrees = 0;
return NULL;
block_stmt_iterator *bsi, bool is_output)
{
/* Shouldn't have gotten called for a scalar. */
- if (elt->replacement)
- abort ();
+ gcc_assert (!elt->replacement);
if (elt->use_block_copy)
{
mark_all_v_defs (stmt);
generate_copy_inout (elt, is_output, other, &list);
- if (list == NULL)
- abort ();
+ mark_all_v_defs (list);
+ gcc_assert (list);
/* Preserve EH semantics. */
if (stmt_ends_bb_p (stmt))
/* Replace the old statement with this new representative. */
bsi_replace (bsi, first, true);
-
+
if (!tsi_end_p (tsi))
{
/* If any reference would trap, then they all would. And more
scalarize_parms (void)
{
tree list = NULL;
- size_t i;
+ unsigned i;
+ bitmap_iterator bi;
- EXECUTE_IF_SET_IN_BITMAP (needs_copy_in, 0, i,
- {
+ EXECUTE_IF_SET_IN_BITMAP (needs_copy_in, 0, i, bi)
+ {
tree var = referenced_var (i);
struct sra_elt *elt = lookup_element (NULL, var, NULL, NO_INSERT);
generate_copy_inout (elt, true, var, &list);
- });
+ }
if (list)
- insert_edge_copies (list, ENTRY_BLOCK_PTR);
+ {
+ insert_edge_copies (list, ENTRY_BLOCK_PTR);
+ mark_all_v_defs (list);
+ }
}
/* Entry point to phase 4. Update the function to match replacements. */
sra_walk_function (&fns);
scalarize_parms ();
- bsi_commit_edge_inserts (NULL);
+ bsi_commit_edge_inserts ();
}
\f
fputc ('\n', stderr);
}
+void
+sra_init_cache (void)
+{
+ if (sra_type_decomp_cache)
+ return;
+
+ sra_type_decomp_cache = BITMAP_ALLOC (NULL);
+ sra_type_inst_cache = BITMAP_ALLOC (NULL);
+}
+
/* Main entry point. */
static void
{
/* Initialize local variables. */
gcc_obstack_init (&sra_obstack);
- sra_candidates = BITMAP_XMALLOC ();
- needs_copy_in = BITMAP_XMALLOC ();
- sra_type_decomp_cache = BITMAP_XMALLOC ();
- sra_type_inst_cache = BITMAP_XMALLOC ();
+ sra_candidates = BITMAP_ALLOC (NULL);
+ needs_copy_in = BITMAP_ALLOC (NULL);
+ sra_init_cache ();
sra_map = htab_create (101, sra_elt_hash, sra_elt_eq, NULL);
/* Scan. If we find anything, instantiate and scalarize. */
/* Free allocated memory. */
htab_delete (sra_map);
sra_map = NULL;
- BITMAP_XFREE (sra_candidates);
- BITMAP_XFREE (needs_copy_in);
- BITMAP_XFREE (sra_type_decomp_cache);
- BITMAP_XFREE (sra_type_inst_cache);
+ BITMAP_FREE (sra_candidates);
+ BITMAP_FREE (needs_copy_in);
+ BITMAP_FREE (sra_type_decomp_cache);
+ BITMAP_FREE (sra_type_inst_cache);
obstack_free (&sra_obstack, NULL);
}
return flag_tree_sra != 0;
}
-struct tree_opt_pass pass_sra =
+struct tree_opt_pass pass_sra =
{
"sra", /* name */
gate_sra, /* gate */
NULL, /* next */
0, /* static_pass_number */
TV_TREE_SRA, /* tv_id */
- PROP_cfg | PROP_ssa, /* properties_required */
+ PROP_cfg | PROP_ssa | PROP_alias, /* properties_required */
0, /* properties_provided */
0, /* properties_destroyed */
0, /* todo_flags_start */
- TODO_dump_func | TODO_rename_vars
- | TODO_ggc_collect | TODO_verify_ssa /* todo_flags_finish */
+ TODO_dump_func | TODO_update_ssa
+ | TODO_ggc_collect | TODO_verify_ssa, /* todo_flags_finish */
+ 0 /* letter */
};