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-rw-r--r--gcc/tree-ssa-dom.c319
1 files changed, 10 insertions, 309 deletions
diff --git a/gcc/tree-ssa-dom.c b/gcc/tree-ssa-dom.c
index 2ec3f97..ad71269 100644
--- a/gcc/tree-ssa-dom.c
+++ b/gcc/tree-ssa-dom.c
@@ -48,15 +48,6 @@ along with GCC; see the file COPYING3. If not see
/* This file implements optimizations on the dominator tree. */
-/* Structure for recording known values of a conditional expression
- at the exits from its block. */
-
-struct cond_equivalence
-{
- struct hashable_expr cond;
- tree value;
-};
-
/* Structure for recording edge equivalences.
Computing and storing the edge equivalences instead of creating
@@ -103,9 +94,6 @@ static struct opt_stats_d opt_stats;
static edge optimize_stmt (basic_block, gimple_stmt_iterator,
class const_and_copies *,
class avail_exprs_stack *);
-static tree lookup_avail_expr (gimple *, bool, class avail_exprs_stack *,
- bool = true);
-static void record_cond (cond_equivalence *, class avail_exprs_stack *);
static void record_equality (tree, tree, class const_and_copies *);
static void record_equivalences_from_phis (basic_block);
static void record_equivalences_from_incoming_edge (basic_block,
@@ -175,148 +163,6 @@ free_all_edge_infos (void)
}
}
-/* Build a cond_equivalence record indicating that the comparison
- CODE holds between operands OP0 and OP1 and push it to **P. */
-
-static void
-build_and_record_new_cond (enum tree_code code,
- tree op0, tree op1,
- vec<cond_equivalence> *p,
- bool val = true)
-{
- cond_equivalence c;
- struct hashable_expr *cond = &c.cond;
-
- gcc_assert (TREE_CODE_CLASS (code) == tcc_comparison);
-
- cond->type = boolean_type_node;
- cond->kind = EXPR_BINARY;
- cond->ops.binary.op = code;
- cond->ops.binary.opnd0 = op0;
- cond->ops.binary.opnd1 = op1;
-
- c.value = val ? boolean_true_node : boolean_false_node;
- p->safe_push (c);
-}
-
-/* Record that COND is true and INVERTED is false into the edge information
- structure. Also record that any conditions dominated by COND are true
- as well.
-
- For example, if a < b is true, then a <= b must also be true. */
-
-static void
-record_conditions (struct edge_info *edge_info, tree cond, tree inverted)
-{
- tree op0, op1;
- cond_equivalence c;
-
- if (!COMPARISON_CLASS_P (cond))
- return;
-
- op0 = TREE_OPERAND (cond, 0);
- op1 = TREE_OPERAND (cond, 1);
-
- switch (TREE_CODE (cond))
- {
- case LT_EXPR:
- case GT_EXPR:
- if (FLOAT_TYPE_P (TREE_TYPE (op0)))
- {
- build_and_record_new_cond (ORDERED_EXPR, op0, op1,
- &edge_info->cond_equivalences);
- build_and_record_new_cond (LTGT_EXPR, op0, op1,
- &edge_info->cond_equivalences);
- }
-
- build_and_record_new_cond ((TREE_CODE (cond) == LT_EXPR
- ? LE_EXPR : GE_EXPR),
- op0, op1, &edge_info->cond_equivalences);
- build_and_record_new_cond (NE_EXPR, op0, op1,
- &edge_info->cond_equivalences);
- build_and_record_new_cond (EQ_EXPR, op0, op1,
- &edge_info->cond_equivalences, false);
- break;
-
- case GE_EXPR:
- case LE_EXPR:
- if (FLOAT_TYPE_P (TREE_TYPE (op0)))
- {
- build_and_record_new_cond (ORDERED_EXPR, op0, op1,
- &edge_info->cond_equivalences);
- }
- break;
-
- case EQ_EXPR:
- if (FLOAT_TYPE_P (TREE_TYPE (op0)))
- {
- build_and_record_new_cond (ORDERED_EXPR, op0, op1,
- &edge_info->cond_equivalences);
- }
- build_and_record_new_cond (LE_EXPR, op0, op1,
- &edge_info->cond_equivalences);
- build_and_record_new_cond (GE_EXPR, op0, op1,
- &edge_info->cond_equivalences);
- break;
-
- case UNORDERED_EXPR:
- build_and_record_new_cond (NE_EXPR, op0, op1,
- &edge_info->cond_equivalences);
- build_and_record_new_cond (UNLE_EXPR, op0, op1,
- &edge_info->cond_equivalences);
- build_and_record_new_cond (UNGE_EXPR, op0, op1,
- &edge_info->cond_equivalences);
- build_and_record_new_cond (UNEQ_EXPR, op0, op1,
- &edge_info->cond_equivalences);
- build_and_record_new_cond (UNLT_EXPR, op0, op1,
- &edge_info->cond_equivalences);
- build_and_record_new_cond (UNGT_EXPR, op0, op1,
- &edge_info->cond_equivalences);
- break;
-
- case UNLT_EXPR:
- case UNGT_EXPR:
- build_and_record_new_cond ((TREE_CODE (cond) == UNLT_EXPR
- ? UNLE_EXPR : UNGE_EXPR),
- op0, op1, &edge_info->cond_equivalences);
- build_and_record_new_cond (NE_EXPR, op0, op1,
- &edge_info->cond_equivalences);
- break;
-
- case UNEQ_EXPR:
- build_and_record_new_cond (UNLE_EXPR, op0, op1,
- &edge_info->cond_equivalences);
- build_and_record_new_cond (UNGE_EXPR, op0, op1,
- &edge_info->cond_equivalences);
- break;
-
- case LTGT_EXPR:
- build_and_record_new_cond (NE_EXPR, op0, op1,
- &edge_info->cond_equivalences);
- build_and_record_new_cond (ORDERED_EXPR, op0, op1,
- &edge_info->cond_equivalences);
- break;
-
- default:
- break;
- }
-
- /* Now store the original true and false conditions into the first
- two slots. */
- initialize_expr_from_cond (cond, &c.cond);
- c.value = boolean_true_node;
- edge_info->cond_equivalences.safe_push (c);
-
- /* It is possible for INVERTED to be the negation of a comparison,
- and not a valid RHS or GIMPLE_COND condition. This happens because
- invert_truthvalue may return such an expression when asked to invert
- a floating-point comparison. These comparisons are not assumed to
- obey the trichotomy law. */
- initialize_expr_from_cond (inverted, &c.cond);
- c.value = boolean_false_node;
- edge_info->cond_equivalences.safe_push (c);
-}
-
/* We have finished optimizing BB, record any information implied by
taking a specific outgoing edge from BB. */
@@ -435,7 +281,7 @@ record_edge_info (basic_block bb)
struct edge_info *edge_info;
edge_info = allocate_edge_info (true_edge);
- record_conditions (edge_info, cond, inverted);
+ record_conditions (&edge_info->cond_equivalences, cond, inverted);
if (can_infer_simple_equiv && code == EQ_EXPR)
{
@@ -444,7 +290,7 @@ record_edge_info (basic_block bb)
}
edge_info = allocate_edge_info (false_edge);
- record_conditions (edge_info, inverted, cond);
+ record_conditions (&edge_info->cond_equivalences, inverted, cond);
if (can_infer_simple_equiv && TREE_CODE (inverted) == EQ_EXPR)
{
@@ -465,7 +311,7 @@ record_edge_info (basic_block bb)
struct edge_info *edge_info;
edge_info = allocate_edge_info (true_edge);
- record_conditions (edge_info, cond, inverted);
+ record_conditions (&edge_info->cond_equivalences, cond, inverted);
if (can_infer_simple_equiv && code == EQ_EXPR)
{
@@ -474,7 +320,7 @@ record_edge_info (basic_block bb)
}
edge_info = allocate_edge_info (false_edge);
- record_conditions (edge_info, inverted, cond);
+ record_conditions (&edge_info->cond_equivalences, inverted, cond);
if (can_infer_simple_equiv && TREE_CODE (inverted) == EQ_EXPR)
{
@@ -760,7 +606,7 @@ simplify_stmt_for_jump_threading (gimple *stmt,
gimple *within_stmt ATTRIBUTE_UNUSED,
class avail_exprs_stack *avail_exprs_stack)
{
- return lookup_avail_expr (stmt, false, avail_exprs_stack);
+ return avail_exprs_stack->lookup_avail_expr (stmt, false, true);
}
/* Valueize hook for gimple_fold_stmt_to_constant_1. */
@@ -865,7 +711,7 @@ record_temporary_equivalences (edge e,
/* If we have 0 = COND or 1 = COND equivalences, record them
into our expression hash tables. */
for (i = 0; edge_info->cond_equivalences.iterate (i, &eq); ++i)
- record_cond (eq, avail_exprs_stack);
+ avail_exprs_stack->record_cond (eq);
tree lhs = edge_info->lhs;
if (!lhs || TREE_CODE (lhs) != SSA_NAME)
@@ -1105,29 +951,6 @@ dump_dominator_optimization_stats (FILE *file,
}
-/* Enter condition equivalence P into AVAIL_EXPRS_HASH.
-
- This indicates that a conditional expression has a known
- boolean value. */
-
-static void
-record_cond (cond_equivalence *p,
- class avail_exprs_stack *avail_exprs_stack)
-{
- class expr_hash_elt *element = new expr_hash_elt (&p->cond, p->value);
- expr_hash_elt **slot;
-
- hash_table<expr_elt_hasher> *avail_exprs = avail_exprs_stack->avail_exprs ();
- slot = avail_exprs->find_slot_with_hash (element, element->hash (), INSERT);
- if (*slot == NULL)
- {
- *slot = element;
- avail_exprs_stack->record_expr (element, NULL, '1');
- }
- else
- delete element;
-}
-
/* Similarly, but assume that X and Y are the two operands of an EQ_EXPR.
This constrains the cases in which we may treat this as assignment. */
@@ -1426,7 +1249,7 @@ eliminate_redundant_computations (gimple_stmt_iterator* gsi,
insert = false;
/* Check if the expression has been computed before. */
- cached_lhs = lookup_avail_expr (stmt, insert, avail_exprs_stack);
+ cached_lhs = avail_exprs_stack->lookup_avail_expr (stmt, insert, true);
opt_stats.num_exprs_considered++;
@@ -1611,7 +1434,7 @@ record_equivalences_from_stmt (gimple *stmt, int may_optimize_p,
/* Finally enter the statement into the available expression
table. */
- lookup_avail_expr (new_stmt, true, avail_exprs_stack);
+ avail_exprs_stack->lookup_avail_expr (new_stmt, true, true);
}
}
@@ -1865,8 +1688,8 @@ optimize_stmt (basic_block bb, gimple_stmt_iterator si,
else
new_stmt = gimple_build_assign (rhs, lhs);
gimple_set_vuse (new_stmt, gimple_vuse (stmt));
- cached_lhs = lookup_avail_expr (new_stmt, false, avail_exprs_stack,
- false);
+ cached_lhs = avail_exprs_stack->lookup_avail_expr (new_stmt, false,
+ false);
if (cached_lhs
&& rhs == cached_lhs)
{
@@ -1942,125 +1765,3 @@ optimize_stmt (basic_block bb, gimple_stmt_iterator si,
}
return retval;
}
-
-/* Helper for walk_non_aliased_vuses. Determine if we arrived at
- the desired memory state. */
-
-static void *
-vuse_eq (ao_ref *, tree vuse1, unsigned int cnt, void *data)
-{
- tree vuse2 = (tree) data;
- if (vuse1 == vuse2)
- return data;
-
- /* This bounds the stmt walks we perform on reference lookups
- to O(1) instead of O(N) where N is the number of dominating
- stores leading to a candidate. We re-use the SCCVN param
- for this as it is basically the same complexity. */
- if (cnt > (unsigned) PARAM_VALUE (PARAM_SCCVN_MAX_ALIAS_QUERIES_PER_ACCESS))
- return (void *)-1;
-
- return NULL;
-}
-
-/* Search for an existing instance of STMT in the AVAIL_EXPRS_STACK table.
- If found, return its LHS. Otherwise insert STMT in the table and
- return NULL_TREE.
-
- Also, when an expression is first inserted in the table, it is also
- is also added to AVAIL_EXPRS_STACK, so that it can be removed when
- we finish processing this block and its children. */
-
-static tree
-lookup_avail_expr (gimple *stmt, bool insert,
- class avail_exprs_stack *avail_exprs_stack, bool tbaa_p)
-{
- expr_hash_elt **slot;
- tree lhs;
-
- /* Get LHS of phi, assignment, or call; else NULL_TREE. */
- if (gimple_code (stmt) == GIMPLE_PHI)
- lhs = gimple_phi_result (stmt);
- else
- lhs = gimple_get_lhs (stmt);
-
- class expr_hash_elt element (stmt, lhs);
-
- if (dump_file && (dump_flags & TDF_DETAILS))
- {
- fprintf (dump_file, "LKUP ");
- element.print (dump_file);
- }
-
- /* Don't bother remembering constant assignments and copy operations.
- Constants and copy operations are handled by the constant/copy propagator
- in optimize_stmt. */
- if (element.expr()->kind == EXPR_SINGLE
- && (TREE_CODE (element.expr()->ops.single.rhs) == SSA_NAME
- || is_gimple_min_invariant (element.expr()->ops.single.rhs)))
- return NULL_TREE;
-
- /* Finally try to find the expression in the main expression hash table. */
- hash_table<expr_elt_hasher> *avail_exprs = avail_exprs_stack->avail_exprs ();
- slot = avail_exprs->find_slot (&element, (insert ? INSERT : NO_INSERT));
- if (slot == NULL)
- {
- return NULL_TREE;
- }
- else if (*slot == NULL)
- {
- class expr_hash_elt *element2 = new expr_hash_elt (element);
- *slot = element2;
-
- avail_exprs_stack->record_expr (element2, NULL, '2');
- return NULL_TREE;
- }
-
- /* If we found a redundant memory operation do an alias walk to
- check if we can re-use it. */
- if (gimple_vuse (stmt) != (*slot)->vop ())
- {
- tree vuse1 = (*slot)->vop ();
- tree vuse2 = gimple_vuse (stmt);
- /* If we have a load of a register and a candidate in the
- hash with vuse1 then try to reach its stmt by walking
- up the virtual use-def chain using walk_non_aliased_vuses.
- But don't do this when removing expressions from the hash. */
- ao_ref ref;
- if (!(vuse1 && vuse2
- && gimple_assign_single_p (stmt)
- && TREE_CODE (gimple_assign_lhs (stmt)) == SSA_NAME
- && (ao_ref_init (&ref, gimple_assign_rhs1 (stmt)),
- ref.base_alias_set = ref.ref_alias_set = tbaa_p ? -1 : 0, true)
- && walk_non_aliased_vuses (&ref, vuse2,
- vuse_eq, NULL, NULL, vuse1) != NULL))
- {
- if (insert)
- {
- class expr_hash_elt *element2 = new expr_hash_elt (element);
-
- /* Insert the expr into the hash by replacing the current
- entry and recording the value to restore in the
- avail_exprs_stack. */
- avail_exprs_stack->record_expr (element2, *slot, '2');
- *slot = element2;
- }
- return NULL_TREE;
- }
- }
-
- /* Extract the LHS of the assignment so that it can be used as the current
- definition of another variable. */
- lhs = (*slot)->lhs ();
-
- lhs = dom_valueize (lhs);
-
- if (dump_file && (dump_flags & TDF_DETAILS))
- {
- fprintf (dump_file, "FIND: ");
- print_generic_expr (dump_file, lhs, 0);
- fprintf (dump_file, "\n");
- }
-
- return lhs;
-}