X-Git-Url: http://git.sourceforge.jp/view?a=blobdiff_plain;f=gcc%2Ftree-ssa-phiopt.c;h=6b15ae09488be00fd039c369a32d06f5e1331d81;hb=ad5e18de84e08637208a4820dc5314674f68019e;hp=2b772db6873653476777b400ed56cab7a974e983;hpb=f2428b62bb52fd982221f7033f53df7c9669dc0b;p=pf3gnuchains%2Fgcc-fork.git
diff --git a/gcc/tree-ssa-phiopt.c b/gcc/tree-ssa-phiopt.c
index 2b772db6873..6b15ae09488 100644
--- a/gcc/tree-ssa-phiopt.c
+++ b/gcc/tree-ssa-phiopt.c
@@ -1,11 +1,12 @@
/* Optimization of PHI nodes by converting them into straightline code.
- Copyright (C) 2004, 2005 Free Software Foundation, Inc.
+ Copyright (C) 2004, 2005, 2006, 2007, 2008, 2009, 2010
+ Free Software Foundation, Inc.
This file is part of GCC.
GCC is free software; you can redistribute it and/or modify it
under the terms of the GNU General Public License as published by the
-Free Software Foundation; either version 2, or (at your option) any
+Free Software Foundation; either version 3, or (at your option) any
later version.
GCC is distributed in the hope that it will be useful, but WITHOUT
@@ -14,9 +15,8 @@ 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, 51 Franklin Street, Fifth Floor, Boston, MA
-02110-1301, USA. */
+along with GCC; see the file COPYING3. If not see
+. */
#include "config.h"
#include "system.h"
@@ -24,28 +24,34 @@ Software Foundation, 51 Franklin Street, Fifth Floor, Boston, MA
#include "tm.h"
#include "ggc.h"
#include "tree.h"
-#include "rtl.h"
#include "flags.h"
#include "tm_p.h"
#include "basic-block.h"
#include "timevar.h"
-#include "diagnostic.h"
#include "tree-flow.h"
#include "tree-pass.h"
#include "tree-dump.h"
#include "langhooks.h"
+#include "pointer-set.h"
+#include "domwalk.h"
+#include "cfgloop.h"
+#include "tree-data-ref.h"
-static void tree_ssa_phiopt (void);
+static unsigned int tree_ssa_phiopt (void);
+static unsigned int tree_ssa_phiopt_worker (bool);
static bool conditional_replacement (basic_block, basic_block,
- edge, edge, tree, tree, tree);
+ edge, edge, gimple, tree, tree);
static bool value_replacement (basic_block, basic_block,
- edge, edge, tree, tree, tree);
+ edge, edge, gimple, tree, tree);
static bool minmax_replacement (basic_block, basic_block,
- edge, edge, tree, tree, tree);
+ edge, edge, gimple, tree, tree);
static bool abs_replacement (basic_block, basic_block,
- edge, edge, tree, tree, tree);
-static void replace_phi_edge_with_variable (basic_block, edge, tree, tree);
-static basic_block *blocks_in_phiopt_order (void);
+ edge, edge, gimple, tree, tree);
+static bool cond_store_replacement (basic_block, basic_block, edge, edge,
+ struct pointer_set_t *);
+static bool cond_if_else_store_replacement (basic_block, basic_block, basic_block);
+static struct pointer_set_t * get_non_trapping (void);
+static void replace_phi_edge_with_variable (basic_block, edge, gimple, tree);
/* This pass tries to replaces an if-then-else block with an
assignment. We have four kinds of transformations. Some of these
@@ -133,12 +139,82 @@ static basic_block *blocks_in_phiopt_order (void);
A similar transformation is done for MAX_EXPR. */
-static void
+static unsigned int
tree_ssa_phiopt (void)
{
+ return tree_ssa_phiopt_worker (false);
+}
+
+/* This pass tries to transform conditional stores into unconditional
+ ones, enabling further simplifications with the simpler then and else
+ blocks. In particular it replaces this:
+
+ bb0:
+ if (cond) goto bb2; else goto bb1;
+ bb1:
+ *p = RHS;
+ bb2:
+
+ with
+
+ bb0:
+ if (cond) goto bb1; else goto bb2;
+ bb1:
+ condtmp' = *p;
+ bb2:
+ condtmp = PHI
+ *p = condtmp;
+
+ This transformation can only be done under several constraints,
+ documented below. It also replaces:
+
+ bb0:
+ if (cond) goto bb2; else goto bb1;
+ bb1:
+ *p = RHS1;
+ goto bb3;
+ bb2:
+ *p = RHS2;
+ bb3:
+
+ with
+
+ bb0:
+ if (cond) goto bb3; else goto bb1;
+ bb1:
+ bb3:
+ condtmp = PHI
+ *p = condtmp; */
+
+static unsigned int
+tree_ssa_cs_elim (void)
+{
+ return tree_ssa_phiopt_worker (true);
+}
+
+/* For conditional store replacement we need a temporary to
+ put the old contents of the memory in. */
+static tree condstoretemp;
+
+/* The core routine of conditional store replacement and normal
+ phi optimizations. Both share much of the infrastructure in how
+ to match applicable basic block patterns. DO_STORE_ELIM is true
+ when we want to do conditional store replacement, false otherwise. */
+static unsigned int
+tree_ssa_phiopt_worker (bool do_store_elim)
+{
basic_block bb;
basic_block *bb_order;
unsigned n, i;
+ bool cfgchanged = false;
+ struct pointer_set_t *nontrap = 0;
+
+ if (do_store_elim)
+ {
+ condstoretemp = NULL_TREE;
+ /* Calculate the set of non-trapping memory accesses. */
+ nontrap = get_non_trapping ();
+ }
/* Search every basic block for COND_EXPR we may be able to optimize.
@@ -150,20 +226,19 @@ tree_ssa_phiopt (void)
bb_order = blocks_in_phiopt_order ();
n = n_basic_blocks - NUM_FIXED_BLOCKS;
- for (i = 0; i < n; i++)
+ for (i = 0; i < n; i++)
{
- tree cond_expr;
- tree phi;
+ gimple cond_stmt, phi;
basic_block bb1, bb2;
edge e1, e2;
tree arg0, arg1;
bb = bb_order[i];
- cond_expr = last_stmt (bb);
- /* Check to see if the last statement is a COND_EXPR. */
- if (!cond_expr
- || TREE_CODE (cond_expr) != COND_EXPR)
+ cond_stmt = last_stmt (bb);
+ /* Check to see if the last statement is a GIMPLE_COND. */
+ if (!cond_stmt
+ || gimple_code (cond_stmt) != GIMPLE_COND)
continue;
e1 = EDGE_SUCC (bb, 0);
@@ -194,8 +269,23 @@ tree_ssa_phiopt (void)
e1 = e2;
e2 = e_tmp;
}
+ else if (do_store_elim
+ && EDGE_SUCC (bb1, 0)->dest == EDGE_SUCC (bb2, 0)->dest)
+ {
+ basic_block bb3 = EDGE_SUCC (bb1, 0)->dest;
+
+ if (!single_succ_p (bb1)
+ || (EDGE_SUCC (bb1, 0)->flags & EDGE_FALLTHRU) == 0
+ || !single_succ_p (bb2)
+ || (EDGE_SUCC (bb2, 0)->flags & EDGE_FALLTHRU) == 0
+ || EDGE_COUNT (bb3->preds) != 2)
+ continue;
+ if (cond_if_else_store_replacement (bb1, bb2, bb3))
+ cfgchanged = true;
+ continue;
+ }
else
- continue;
+ continue;
e1 = EDGE_SUCC (bb1, 0);
@@ -210,50 +300,90 @@ tree_ssa_phiopt (void)
|| single_pred (bb1) != bb)
continue;
- phi = phi_nodes (bb2);
-
- /* Check to make sure that there is only one PHI node.
- TODO: we could do it with more than one iff the other PHI nodes
- have the same elements for these two edges. */
- if (!phi || PHI_CHAIN (phi) != NULL)
- continue;
-
- arg0 = PHI_ARG_DEF_TREE (phi, e1->dest_idx);
- arg1 = PHI_ARG_DEF_TREE (phi, e2->dest_idx);
-
- /* Something is wrong if we cannot find the arguments in the PHI
- node. */
- gcc_assert (arg0 != NULL && arg1 != NULL);
-
- /* Do the replacement of conditional if it can be done. */
- if (conditional_replacement (bb, bb1, e1, e2, phi, arg0, arg1))
- ;
- else if (value_replacement (bb, bb1, e1, e2, phi, arg0, arg1))
- ;
- else if (abs_replacement (bb, bb1, e1, e2, phi, arg0, arg1))
- ;
+ if (do_store_elim)
+ {
+ /* bb1 is the middle block, bb2 the join block, bb the split block,
+ e1 the fallthrough edge from bb1 to bb2. We can't do the
+ optimization if the join block has more than two predecessors. */
+ if (EDGE_COUNT (bb2->preds) > 2)
+ continue;
+ if (cond_store_replacement (bb1, bb2, e1, e2, nontrap))
+ cfgchanged = true;
+ }
else
- minmax_replacement (bb, bb1, e1, e2, phi, arg0, arg1);
+ {
+ gimple_seq phis = phi_nodes (bb2);
+ gimple_stmt_iterator gsi;
+
+ /* Check to make sure that there is only one non-virtual PHI node.
+ TODO: we could do it with more than one iff the other PHI nodes
+ have the same elements for these two edges. */
+ phi = NULL;
+ for (gsi = gsi_start (phis); !gsi_end_p (gsi); gsi_next (&gsi))
+ {
+ if (!is_gimple_reg (gimple_phi_result (gsi_stmt (gsi))))
+ continue;
+ if (phi)
+ {
+ phi = NULL;
+ break;
+ }
+ phi = gsi_stmt (gsi);
+ }
+ if (!phi)
+ continue;
+
+ arg0 = gimple_phi_arg_def (phi, e1->dest_idx);
+ arg1 = gimple_phi_arg_def (phi, e2->dest_idx);
+
+ /* Something is wrong if we cannot find the arguments in the PHI
+ node. */
+ gcc_assert (arg0 != NULL && arg1 != NULL);
+
+ /* Do the replacement of conditional if it can be done. */
+ if (conditional_replacement (bb, bb1, e1, e2, phi, arg0, arg1))
+ cfgchanged = true;
+ else if (value_replacement (bb, bb1, e1, e2, phi, arg0, arg1))
+ cfgchanged = true;
+ else if (abs_replacement (bb, bb1, e1, e2, phi, arg0, arg1))
+ cfgchanged = true;
+ else if (minmax_replacement (bb, bb1, e1, e2, phi, arg0, arg1))
+ cfgchanged = true;
+ }
}
free (bb_order);
+
+ if (do_store_elim)
+ pointer_set_destroy (nontrap);
+ /* If the CFG has changed, we should cleanup the CFG. */
+ if (cfgchanged && do_store_elim)
+ {
+ /* In cond-store replacement we have added some loads on edges
+ and new VOPS (as we moved the store, and created a load). */
+ gsi_commit_edge_inserts ();
+ return TODO_cleanup_cfg | TODO_update_ssa_only_virtuals;
+ }
+ else if (cfgchanged)
+ return TODO_cleanup_cfg;
+ return 0;
}
/* Returns the list of basic blocks in the function in an order that guarantees
that if a block X has just a single predecessor Y, then Y is after X in the
ordering. */
-static basic_block *
+basic_block *
blocks_in_phiopt_order (void)
{
basic_block x, y;
basic_block *order = XNEWVEC (basic_block, n_basic_blocks);
- unsigned n = n_basic_blocks - NUM_FIXED_BLOCKS;
+ unsigned n = n_basic_blocks - NUM_FIXED_BLOCKS;
unsigned np, i;
- sbitmap visited = sbitmap_alloc (last_basic_block);
+ sbitmap visited = sbitmap_alloc (last_basic_block);
-#define MARK_VISITED(BB) (SET_BIT (visited, (BB)->index))
-#define VISITED_P(BB) (TEST_BIT (visited, (BB)->index))
+#define MARK_VISITED(BB) (SET_BIT (visited, (BB)->index))
+#define VISITED_P(BB) (TEST_BIT (visited, (BB)->index))
sbitmap_zero (visited);
@@ -292,24 +422,20 @@ blocks_in_phiopt_order (void)
#undef VISITED_P
}
+
/* Return TRUE if block BB has no executable statements, otherwise return
FALSE. */
+
bool
empty_block_p (basic_block bb)
{
- block_stmt_iterator bsi;
-
/* BB must have no executable statements. */
- bsi = bsi_start (bb);
- while (!bsi_end_p (bsi)
- && (TREE_CODE (bsi_stmt (bsi)) == LABEL_EXPR
- || IS_EMPTY_STMT (bsi_stmt (bsi))))
- bsi_next (&bsi);
-
- if (!bsi_end_p (bsi))
- return false;
-
- return true;
+ gimple_stmt_iterator gsi = gsi_after_labels (bb);
+ if (gsi_end_p (gsi))
+ return true;
+ if (is_gimple_debug (gsi_stmt (gsi)))
+ gsi_next_nondebug (&gsi);
+ return gsi_end_p (gsi);
}
/* Replace PHI node element whose edge is E in block BB with variable NEW.
@@ -318,14 +444,14 @@ empty_block_p (basic_block bb)
static void
replace_phi_edge_with_variable (basic_block cond_block,
- edge e, tree phi, tree new)
+ edge e, gimple phi, tree new_tree)
{
- basic_block bb = bb_for_stmt (phi);
+ basic_block bb = gimple_bb (phi);
basic_block block_to_remove;
- block_stmt_iterator bsi;
+ gimple_stmt_iterator gsi;
/* Change the PHI argument to new. */
- SET_USE (PHI_ARG_DEF_PTR (phi, e->dest_idx), new);
+ SET_USE (PHI_ARG_DEF_PTR (phi, e->dest_idx), new_tree);
/* Remove the empty basic block. */
if (EDGE_SUCC (cond_block, 0)->dest == bb)
@@ -350,8 +476,8 @@ replace_phi_edge_with_variable (basic_block cond_block,
delete_basic_block (block_to_remove);
/* Eliminate the COND_EXPR at the end of COND_BLOCK. */
- bsi = bsi_last (cond_block);
- bsi_remove (&bsi, true);
+ gsi = gsi_last_bb (cond_block);
+ gsi_remove (&gsi, true);
if (dump_file && (dump_flags & TDF_DETAILS))
fprintf (dump_file,
@@ -368,16 +494,20 @@ replace_phi_edge_with_variable (basic_block cond_block,
static bool
conditional_replacement (basic_block cond_bb, basic_block middle_bb,
- edge e0, edge e1, tree phi,
+ edge e0, edge e1, gimple phi,
tree arg0, tree arg1)
{
tree result;
- tree old_result = NULL;
- tree new, cond;
- block_stmt_iterator bsi;
+ gimple stmt, new_stmt;
+ tree cond;
+ gimple_stmt_iterator gsi;
edge true_edge, false_edge;
- tree new_var = NULL;
- tree new_var1;
+ tree new_var, new_var2;
+
+ /* FIXME: Gimplification of complex type is too hard for now. */
+ if (TREE_CODE (TREE_TYPE (arg0)) == COMPLEX_TYPE
+ || TREE_CODE (TREE_TYPE (arg1)) == COMPLEX_TYPE)
+ return false;
/* The PHI arguments have the constants 0 and 1, then convert
it to the conditional. */
@@ -390,61 +520,7 @@ conditional_replacement (basic_block cond_bb, basic_block middle_bb,
if (!empty_block_p (middle_bb))
return false;
- /* If the condition is not a naked SSA_NAME and its type does not
- match the type of the result, then we have to create a new
- variable to optimize this case as it would likely create
- non-gimple code when the condition was converted to the
- result's type. */
- cond = COND_EXPR_COND (last_stmt (cond_bb));
- result = PHI_RESULT (phi);
- if (TREE_CODE (cond) != SSA_NAME
- && !lang_hooks.types_compatible_p (TREE_TYPE (cond), TREE_TYPE (result)))
- {
- tree tmp;
-
- if (!COMPARISON_CLASS_P (cond))
- return false;
-
- tmp = create_tmp_var (TREE_TYPE (cond), NULL);
- add_referenced_tmp_var (tmp);
- new_var = make_ssa_name (tmp, NULL);
- old_result = cond;
- cond = new_var;
- }
-
- /* If the condition was a naked SSA_NAME and the type is not the
- same as the type of the result, then convert the type of the
- condition. */
- if (!lang_hooks.types_compatible_p (TREE_TYPE (cond), TREE_TYPE (result)))
- cond = fold_convert (TREE_TYPE (result), cond);
-
- /* We need to know which is the true edge and which is the false
- edge so that we know when to invert the condition below. */
- extract_true_false_edges_from_block (cond_bb, &true_edge, &false_edge);
-
- /* Insert our new statement at the end of conditional block before the
- COND_EXPR. */
- bsi = bsi_last (cond_bb);
- bsi_insert_before (&bsi, build_empty_stmt (), BSI_NEW_STMT);
-
- if (old_result)
- {
- tree new1;
-
- new1 = build2 (TREE_CODE (old_result), TREE_TYPE (old_result),
- TREE_OPERAND (old_result, 0),
- TREE_OPERAND (old_result, 1));
-
- new1 = build2 (MODIFY_EXPR, TREE_TYPE (old_result), new_var, new1);
- SSA_NAME_DEF_STMT (new_var) = new1;
-
- bsi_insert_after (&bsi, new1, BSI_NEW_STMT);
- }
-
- new_var1 = duplicate_ssa_name (PHI_RESULT (phi), NULL);
-
-
- /* At this point we know we have a COND_EXPR with two successors.
+ /* At this point we know we have a GIMPLE_COND with two successors.
One successor is BB, the other successor is an empty block which
falls through into BB.
@@ -459,72 +535,55 @@ conditional_replacement (basic_block cond_bb, basic_block middle_bb,
We use the condition as-is if the argument associated with the
true edge has the value one or the argument associated with the
false edge as the value zero. Note that those conditions are not
- the same since only one of the outgoing edges from the COND_EXPR
+ the same since only one of the outgoing edges from the GIMPLE_COND
will directly reach BB and thus be associated with an argument. */
- if ((e0 == true_edge && integer_onep (arg0))
- || (e0 == false_edge && integer_zerop (arg0))
- || (e1 == true_edge && integer_onep (arg1))
- || (e1 == false_edge && integer_zerop (arg1)))
- {
- new = build2 (MODIFY_EXPR, TREE_TYPE (new_var1), new_var1, cond);
- }
- else
- {
- tree cond1 = invert_truthvalue (cond);
-
- cond = cond1;
- /* If what we get back is a conditional expression, there is no
- way that it can be gimple. */
- if (TREE_CODE (cond) == COND_EXPR)
- {
- release_ssa_name (new_var1);
- return false;
- }
+ stmt = last_stmt (cond_bb);
+ result = PHI_RESULT (phi);
- /* If COND is not something we can expect to be reducible to a GIMPLE
- condition, return early. */
- if (is_gimple_cast (cond))
- cond1 = TREE_OPERAND (cond, 0);
- if (TREE_CODE (cond1) == TRUTH_NOT_EXPR
- && !is_gimple_val (TREE_OPERAND (cond1, 0)))
- {
- release_ssa_name (new_var1);
- return false;
- }
+ /* To handle special cases like floating point comparison, it is easier and
+ less error-prone to build a tree and gimplify it on the fly though it is
+ less efficient. */
+ cond = fold_build2 (gimple_cond_code (stmt), boolean_type_node,
+ gimple_cond_lhs (stmt), gimple_cond_rhs (stmt));
- /* If what we get back is not gimple try to create it as gimple by
- using a temporary variable. */
- if (is_gimple_cast (cond)
- && !is_gimple_val (TREE_OPERAND (cond, 0)))
- {
- tree op0, tmp, cond_tmp;
-
- /* Only "real" casts are OK here, not everything that is
- acceptable to is_gimple_cast. Make sure we don't do
- anything stupid here. */
- gcc_assert (TREE_CODE (cond) == NOP_EXPR
- || TREE_CODE (cond) == CONVERT_EXPR);
-
- op0 = TREE_OPERAND (cond, 0);
- tmp = create_tmp_var (TREE_TYPE (op0), NULL);
- add_referenced_tmp_var (tmp);
- cond_tmp = make_ssa_name (tmp, NULL);
- new = build2 (MODIFY_EXPR, TREE_TYPE (cond_tmp), cond_tmp, op0);
- SSA_NAME_DEF_STMT (cond_tmp) = new;
-
- bsi_insert_after (&bsi, new, BSI_NEW_STMT);
- cond = fold_convert (TREE_TYPE (result), cond_tmp);
- }
-
- new = build2 (MODIFY_EXPR, TREE_TYPE (new_var1), new_var1, cond);
+ /* We need to know which is the true edge and which is the false
+ edge so that we know when to invert the condition below. */
+ extract_true_false_edges_from_block (cond_bb, &true_edge, &false_edge);
+ if ((e0 == true_edge && integer_zerop (arg0))
+ || (e0 == false_edge && integer_onep (arg0))
+ || (e1 == true_edge && integer_zerop (arg1))
+ || (e1 == false_edge && integer_onep (arg1)))
+ cond = fold_build1 (TRUTH_NOT_EXPR, TREE_TYPE (cond), cond);
+
+ /* Insert our new statements at the end of conditional block before the
+ COND_STMT. */
+ gsi = gsi_for_stmt (stmt);
+ new_var = force_gimple_operand_gsi (&gsi, cond, true, NULL, true,
+ GSI_SAME_STMT);
+
+ if (!useless_type_conversion_p (TREE_TYPE (result), TREE_TYPE (new_var)))
+ {
+ source_location locus_0, locus_1;
+
+ new_var2 = create_tmp_var (TREE_TYPE (result), NULL);
+ add_referenced_var (new_var2);
+ new_stmt = gimple_build_assign_with_ops (CONVERT_EXPR, new_var2,
+ new_var, NULL);
+ new_var2 = make_ssa_name (new_var2, new_stmt);
+ gimple_assign_set_lhs (new_stmt, new_var2);
+ gsi_insert_before (&gsi, new_stmt, GSI_SAME_STMT);
+ new_var = new_var2;
+
+ /* Set the locus to the first argument, unless is doesn't have one. */
+ locus_0 = gimple_phi_arg_location (phi, 0);
+ locus_1 = gimple_phi_arg_location (phi, 1);
+ if (locus_0 == UNKNOWN_LOCATION)
+ locus_0 = locus_1;
+ gimple_set_location (new_stmt, locus_0);
}
- bsi_insert_after (&bsi, new, BSI_NEW_STMT);
-
- SSA_NAME_DEF_STMT (new_var1) = new;
-
- replace_phi_edge_with_variable (cond_bb, e1, phi, new_var1);
+ replace_phi_edge_with_variable (cond_bb, e1, phi, new_var);
/* Note that we optimized this PHI. */
return true;
@@ -538,11 +597,12 @@ conditional_replacement (basic_block cond_bb, basic_block middle_bb,
static bool
value_replacement (basic_block cond_bb, basic_block middle_bb,
- edge e0, edge e1, tree phi,
+ edge e0, edge e1, gimple phi,
tree arg0, tree arg1)
{
- tree cond;
+ gimple cond;
edge true_edge, false_edge;
+ enum tree_code code;
/* If the type says honor signed zeros we cannot do this
optimization. */
@@ -552,10 +612,11 @@ value_replacement (basic_block cond_bb, basic_block middle_bb,
if (!empty_block_p (middle_bb))
return false;
- cond = COND_EXPR_COND (last_stmt (cond_bb));
+ cond = last_stmt (cond_bb);
+ code = gimple_cond_code (cond);
/* This transformation is only valid for equality comparisons. */
- if (TREE_CODE (cond) != NE_EXPR && TREE_CODE (cond) != EQ_EXPR)
+ if (code != NE_EXPR && code != EQ_EXPR)
return false;
/* We need to know which is the true edge and which is the false
@@ -573,10 +634,10 @@ value_replacement (basic_block cond_bb, basic_block middle_bb,
We now need to verify that the two arguments in the PHI node match
the two arguments to the equality comparison. */
- if ((operand_equal_for_phi_arg_p (arg0, TREE_OPERAND (cond, 0))
- && operand_equal_for_phi_arg_p (arg1, TREE_OPERAND (cond, 1)))
- || (operand_equal_for_phi_arg_p (arg1, TREE_OPERAND (cond, 0))
- && operand_equal_for_phi_arg_p (arg0, TREE_OPERAND (cond, 1))))
+ if ((operand_equal_for_phi_arg_p (arg0, gimple_cond_lhs (cond))
+ && operand_equal_for_phi_arg_p (arg1, gimple_cond_rhs (cond)))
+ || (operand_equal_for_phi_arg_p (arg1, gimple_cond_lhs (cond))
+ && operand_equal_for_phi_arg_p (arg0, gimple_cond_rhs (cond))))
{
edge e;
tree arg;
@@ -584,7 +645,7 @@ value_replacement (basic_block cond_bb, basic_block middle_bb,
/* For NE_EXPR, we want to build an assignment result = arg where
arg is the PHI argument associated with the true edge. For
EQ_EXPR we want the PHI argument associated with the false edge. */
- e = (TREE_CODE (cond) == NE_EXPR ? true_edge : false_edge);
+ e = (code == NE_EXPR ? true_edge : false_edge);
/* Unfortunately, E may not reach BB (it may instead have gone to
OTHER_BLOCK). If that is the case, then we want the single outgoing
@@ -616,15 +677,15 @@ value_replacement (basic_block cond_bb, basic_block middle_bb,
static bool
minmax_replacement (basic_block cond_bb, basic_block middle_bb,
- edge e0, edge e1, tree phi,
+ edge e0, edge e1, gimple phi,
tree arg0, tree arg1)
{
tree result, type;
- tree cond, new;
+ gimple cond, new_stmt;
edge true_edge, false_edge;
enum tree_code cmp, minmax, ass_code;
tree smaller, larger, arg_true, arg_false;
- block_stmt_iterator bsi, bsi_from;
+ gimple_stmt_iterator gsi, gsi_from;
type = TREE_TYPE (PHI_RESULT (phi));
@@ -632,21 +693,20 @@ minmax_replacement (basic_block cond_bb, basic_block middle_bb,
if (HONOR_NANS (TYPE_MODE (type)))
return false;
- cond = COND_EXPR_COND (last_stmt (cond_bb));
- cmp = TREE_CODE (cond);
- result = PHI_RESULT (phi);
+ cond = last_stmt (cond_bb);
+ cmp = gimple_cond_code (cond);
/* This transformation is only valid for order comparisons. Record which
operand is smaller/larger if the result of the comparison is true. */
if (cmp == LT_EXPR || cmp == LE_EXPR)
{
- smaller = TREE_OPERAND (cond, 0);
- larger = TREE_OPERAND (cond, 1);
+ smaller = gimple_cond_lhs (cond);
+ larger = gimple_cond_rhs (cond);
}
else if (cmp == GT_EXPR || cmp == GE_EXPR)
{
- smaller = TREE_OPERAND (cond, 1);
- larger = TREE_OPERAND (cond, 0);
+ smaller = gimple_cond_rhs (cond);
+ larger = gimple_cond_lhs (cond);
}
else
return false;
@@ -681,7 +741,7 @@ minmax_replacement (basic_block cond_bb, basic_block middle_bb,
&& operand_equal_for_phi_arg_p (arg_false, larger))
{
/* Case
-
+
if (smaller < larger)
rslt = smaller;
else
@@ -707,20 +767,19 @@ minmax_replacement (basic_block cond_bb, basic_block middle_bb,
b = MAX (a, d);
x = MIN (b, u); */
- tree assign = last_and_only_stmt (middle_bb);
- tree lhs, rhs, op0, op1, bound;
+ gimple assign = last_and_only_stmt (middle_bb);
+ tree lhs, op0, op1, bound;
if (!assign
- || TREE_CODE (assign) != MODIFY_EXPR)
+ || gimple_code (assign) != GIMPLE_ASSIGN)
return false;
- lhs = TREE_OPERAND (assign, 0);
- rhs = TREE_OPERAND (assign, 1);
- ass_code = TREE_CODE (rhs);
+ lhs = gimple_assign_lhs (assign);
+ ass_code = gimple_assign_rhs_code (assign);
if (ass_code != MAX_EXPR && ass_code != MIN_EXPR)
return false;
- op0 = TREE_OPERAND (rhs, 0);
- op1 = TREE_OPERAND (rhs, 1);
+ op0 = gimple_assign_rhs1 (assign);
+ op1 = gimple_assign_rhs2 (assign);
if (true_edge->src == middle_bb)
{
@@ -842,18 +901,16 @@ minmax_replacement (basic_block cond_bb, basic_block middle_bb,
}
/* Move the statement from the middle block. */
- bsi = bsi_last (cond_bb);
- bsi_from = bsi_last (middle_bb);
- bsi_move_before (&bsi_from, &bsi);
+ gsi = gsi_last_bb (cond_bb);
+ gsi_from = gsi_last_nondebug_bb (middle_bb);
+ gsi_move_before (&gsi_from, &gsi);
}
/* Emit the statement to compute min/max. */
result = duplicate_ssa_name (PHI_RESULT (phi), NULL);
- new = build2 (MODIFY_EXPR, type, result,
- build2 (minmax, type, arg0, arg1));
- SSA_NAME_DEF_STMT (result) = new;
- bsi = bsi_last (cond_bb);
- bsi_insert_before (&bsi, new, BSI_NEW_STMT);
+ new_stmt = gimple_build_assign_with_ops (minmax, result, arg0, arg1);
+ gsi = gsi_last_bb (cond_bb);
+ gsi_insert_before (&gsi, new_stmt, GSI_NEW_STMT);
replace_phi_edge_with_variable (cond_bb, e1, phi, result);
return true;
@@ -868,13 +925,13 @@ minmax_replacement (basic_block cond_bb, basic_block middle_bb,
static bool
abs_replacement (basic_block cond_bb, basic_block middle_bb,
edge e0 ATTRIBUTE_UNUSED, edge e1,
- tree phi, tree arg0, tree arg1)
+ gimple phi, tree arg0, tree arg1)
{
tree result;
- tree new, cond;
- block_stmt_iterator bsi;
+ gimple new_stmt, cond;
+ gimple_stmt_iterator gsi;
edge true_edge, false_edge;
- tree assign;
+ gimple assign;
edge e;
tree rhs, lhs;
bool negate;
@@ -893,42 +950,41 @@ abs_replacement (basic_block cond_bb, basic_block middle_bb,
optimize. */
if (assign == NULL)
return false;
-
+
/* If we got here, then we have found the only executable statement
in OTHER_BLOCK. If it is anything other than arg = -arg1 or
arg1 = -arg0, then we can not optimize. */
- if (TREE_CODE (assign) != MODIFY_EXPR)
+ if (gimple_code (assign) != GIMPLE_ASSIGN)
return false;
- lhs = TREE_OPERAND (assign, 0);
- rhs = TREE_OPERAND (assign, 1);
+ lhs = gimple_assign_lhs (assign);
- if (TREE_CODE (rhs) != NEGATE_EXPR)
+ if (gimple_assign_rhs_code (assign) != NEGATE_EXPR)
return false;
- rhs = TREE_OPERAND (rhs, 0);
-
+ rhs = gimple_assign_rhs1 (assign);
+
/* The assignment has to be arg0 = -arg1 or arg1 = -arg0. */
if (!(lhs == arg0 && rhs == arg1)
&& !(lhs == arg1 && rhs == arg0))
return false;
- cond = COND_EXPR_COND (last_stmt (cond_bb));
+ cond = last_stmt (cond_bb);
result = PHI_RESULT (phi);
/* Only relationals comparing arg[01] against zero are interesting. */
- cond_code = TREE_CODE (cond);
+ cond_code = gimple_cond_code (cond);
if (cond_code != GT_EXPR && cond_code != GE_EXPR
&& cond_code != LT_EXPR && cond_code != LE_EXPR)
return false;
/* Make sure the conditional is arg[01] OP y. */
- if (TREE_OPERAND (cond, 0) != rhs)
+ if (gimple_cond_lhs (cond) != rhs)
return false;
- if (FLOAT_TYPE_P (TREE_TYPE (TREE_OPERAND (cond, 1)))
- ? real_zerop (TREE_OPERAND (cond, 1))
- : integer_zerop (TREE_OPERAND (cond, 1)))
+ if (FLOAT_TYPE_P (TREE_TYPE (gimple_cond_rhs (cond)))
+ ? real_zerop (gimple_cond_rhs (cond))
+ : integer_zerop (gimple_cond_rhs (cond)))
;
else
return false;
@@ -955,30 +1011,26 @@ abs_replacement (basic_block cond_bb, basic_block middle_bb,
if (negate)
{
tree tmp = create_tmp_var (TREE_TYPE (result), NULL);
- add_referenced_tmp_var (tmp);
+ add_referenced_var (tmp);
lhs = make_ssa_name (tmp, NULL);
}
else
lhs = result;
/* Build the modify expression with abs expression. */
- new = build2 (MODIFY_EXPR, TREE_TYPE (lhs),
- lhs, build1 (ABS_EXPR, TREE_TYPE (lhs), rhs));
- SSA_NAME_DEF_STMT (lhs) = new;
+ new_stmt = gimple_build_assign_with_ops (ABS_EXPR, lhs, rhs, NULL);
- bsi = bsi_last (cond_bb);
- bsi_insert_before (&bsi, new, BSI_NEW_STMT);
+ gsi = gsi_last_bb (cond_bb);
+ gsi_insert_before (&gsi, new_stmt, GSI_NEW_STMT);
if (negate)
{
- /* Get the right BSI. We want to insert after the recently
+ /* Get the right GSI. We want to insert after the recently
added ABS_EXPR statement (which we know is the first statement
in the block. */
- new = build2 (MODIFY_EXPR, TREE_TYPE (result),
- result, build1 (NEGATE_EXPR, TREE_TYPE (lhs), lhs));
- SSA_NAME_DEF_STMT (result) = new;
+ new_stmt = gimple_build_assign_with_ops (NEGATE_EXPR, result, lhs, NULL);
- bsi_insert_after (&bsi, new, BSI_NEW_STMT);
+ gsi_insert_after (&gsi, new_stmt, GSI_NEW_STMT);
}
replace_phi_edge_with_variable (cond_bb, e1, phi, result);
@@ -987,6 +1039,531 @@ abs_replacement (basic_block cond_bb, basic_block middle_bb,
return true;
}
+/* Auxiliary functions to determine the set of memory accesses which
+ can't trap because they are preceded by accesses to the same memory
+ portion. We do that for MEM_REFs, so we only need to track
+ the SSA_NAME of the pointer indirectly referenced. The algorithm
+ simply is a walk over all instructions in dominator order. When
+ we see an MEM_REF we determine if we've already seen a same
+ ref anywhere up to the root of the dominator tree. If we do the
+ current access can't trap. If we don't see any dominating access
+ the current access might trap, but might also make later accesses
+ non-trapping, so we remember it. We need to be careful with loads
+ or stores, for instance a load might not trap, while a store would,
+ so if we see a dominating read access this doesn't mean that a later
+ write access would not trap. Hence we also need to differentiate the
+ type of access(es) seen.
+
+ ??? We currently are very conservative and assume that a load might
+ trap even if a store doesn't (write-only memory). This probably is
+ overly conservative. */
+
+/* A hash-table of SSA_NAMEs, and in which basic block an MEM_REF
+ through it was seen, which would constitute a no-trap region for
+ same accesses. */
+struct name_to_bb
+{
+ tree ssa_name;
+ basic_block bb;
+ unsigned store : 1;
+};
+
+/* The hash table for remembering what we've seen. */
+static htab_t seen_ssa_names;
+
+/* The set of MEM_REFs which can't trap. */
+static struct pointer_set_t *nontrap_set;
+
+/* The hash function, based on the pointer to the pointer SSA_NAME. */
+static hashval_t
+name_to_bb_hash (const void *p)
+{
+ const_tree n = ((const struct name_to_bb *)p)->ssa_name;
+ return htab_hash_pointer (n) ^ ((const struct name_to_bb *)p)->store;
+}
+
+/* The equality function of *P1 and *P2. SSA_NAMEs are shared, so
+ it's enough to simply compare them for equality. */
+static int
+name_to_bb_eq (const void *p1, const void *p2)
+{
+ const struct name_to_bb *n1 = (const struct name_to_bb *)p1;
+ const struct name_to_bb *n2 = (const struct name_to_bb *)p2;
+
+ return n1->ssa_name == n2->ssa_name && n1->store == n2->store;
+}
+
+/* We see the expression EXP in basic block BB. If it's an interesting
+ expression (an MEM_REF through an SSA_NAME) possibly insert the
+ expression into the set NONTRAP or the hash table of seen expressions.
+ STORE is true if this expression is on the LHS, otherwise it's on
+ the RHS. */
+static void
+add_or_mark_expr (basic_block bb, tree exp,
+ struct pointer_set_t *nontrap, bool store)
+{
+ if (TREE_CODE (exp) == MEM_REF
+ && TREE_CODE (TREE_OPERAND (exp, 0)) == SSA_NAME)
+ {
+ tree name = TREE_OPERAND (exp, 0);
+ struct name_to_bb map;
+ void **slot;
+ struct name_to_bb *n2bb;
+ basic_block found_bb = 0;
+
+ /* Try to find the last seen MEM_REF through the same
+ SSA_NAME, which can trap. */
+ map.ssa_name = name;
+ map.bb = 0;
+ map.store = store;
+ slot = htab_find_slot (seen_ssa_names, &map, INSERT);
+ n2bb = (struct name_to_bb *) *slot;
+ if (n2bb)
+ found_bb = n2bb->bb;
+
+ /* If we've found a trapping MEM_REF, _and_ it dominates EXP
+ (it's in a basic block on the path from us to the dominator root)
+ then we can't trap. */
+ if (found_bb && found_bb->aux == (void *)1)
+ {
+ pointer_set_insert (nontrap, exp);
+ }
+ else
+ {
+ /* EXP might trap, so insert it into the hash table. */
+ if (n2bb)
+ {
+ n2bb->bb = bb;
+ }
+ else
+ {
+ n2bb = XNEW (struct name_to_bb);
+ n2bb->ssa_name = name;
+ n2bb->bb = bb;
+ n2bb->store = store;
+ *slot = n2bb;
+ }
+ }
+ }
+}
+
+/* Called by walk_dominator_tree, when entering the block BB. */
+static void
+nt_init_block (struct dom_walk_data *data ATTRIBUTE_UNUSED, basic_block bb)
+{
+ gimple_stmt_iterator gsi;
+ /* Mark this BB as being on the path to dominator root. */
+ bb->aux = (void*)1;
+
+ /* And walk the statements in order. */
+ for (gsi = gsi_start_bb (bb); !gsi_end_p (gsi); gsi_next (&gsi))
+ {
+ gimple stmt = gsi_stmt (gsi);
+
+ if (is_gimple_assign (stmt))
+ {
+ add_or_mark_expr (bb, gimple_assign_lhs (stmt), nontrap_set, true);
+ add_or_mark_expr (bb, gimple_assign_rhs1 (stmt), nontrap_set, false);
+ if (get_gimple_rhs_num_ops (gimple_assign_rhs_code (stmt)) > 1)
+ add_or_mark_expr (bb, gimple_assign_rhs2 (stmt), nontrap_set,
+ false);
+ }
+ }
+}
+
+/* Called by walk_dominator_tree, when basic block BB is exited. */
+static void
+nt_fini_block (struct dom_walk_data *data ATTRIBUTE_UNUSED, basic_block bb)
+{
+ /* This BB isn't on the path to dominator root anymore. */
+ bb->aux = NULL;
+}
+
+/* This is the entry point of gathering non trapping memory accesses.
+ It will do a dominator walk over the whole function, and it will
+ make use of the bb->aux pointers. It returns a set of trees
+ (the MEM_REFs itself) which can't trap. */
+static struct pointer_set_t *
+get_non_trapping (void)
+{
+ struct pointer_set_t *nontrap;
+ struct dom_walk_data walk_data;
+
+ nontrap = pointer_set_create ();
+ seen_ssa_names = htab_create (128, name_to_bb_hash, name_to_bb_eq,
+ free);
+ /* We're going to do a dominator walk, so ensure that we have
+ dominance information. */
+ calculate_dominance_info (CDI_DOMINATORS);
+
+ /* Setup callbacks for the generic dominator tree walker. */
+ nontrap_set = nontrap;
+ walk_data.dom_direction = CDI_DOMINATORS;
+ walk_data.initialize_block_local_data = NULL;
+ walk_data.before_dom_children = nt_init_block;
+ walk_data.after_dom_children = nt_fini_block;
+ walk_data.global_data = NULL;
+ walk_data.block_local_data_size = 0;
+
+ init_walk_dominator_tree (&walk_data);
+ walk_dominator_tree (&walk_data, ENTRY_BLOCK_PTR);
+ fini_walk_dominator_tree (&walk_data);
+ htab_delete (seen_ssa_names);
+
+ return nontrap;
+}
+
+/* Do the main work of conditional store replacement. We already know
+ that the recognized pattern looks like so:
+
+ split:
+ if (cond) goto MIDDLE_BB; else goto JOIN_BB (edge E1)
+ MIDDLE_BB:
+ something
+ fallthrough (edge E0)
+ JOIN_BB:
+ some more
+
+ We check that MIDDLE_BB contains only one store, that that store
+ doesn't trap (not via NOTRAP, but via checking if an access to the same
+ memory location dominates us) and that the store has a "simple" RHS. */
+
+static bool
+cond_store_replacement (basic_block middle_bb, basic_block join_bb,
+ edge e0, edge e1, struct pointer_set_t *nontrap)
+{
+ gimple assign = last_and_only_stmt (middle_bb);
+ tree lhs, rhs, name;
+ gimple newphi, new_stmt;
+ gimple_stmt_iterator gsi;
+ source_location locus;
+
+ /* Check if middle_bb contains of only one store. */
+ if (!assign
+ || !gimple_assign_single_p (assign))
+ return false;
+
+ locus = gimple_location (assign);
+ lhs = gimple_assign_lhs (assign);
+ rhs = gimple_assign_rhs1 (assign);
+ if (TREE_CODE (lhs) != MEM_REF
+ || TREE_CODE (TREE_OPERAND (lhs, 0)) != SSA_NAME
+ || !is_gimple_reg_type (TREE_TYPE (lhs)))
+ return false;
+
+ /* Prove that we can move the store down. We could also check
+ TREE_THIS_NOTRAP here, but in that case we also could move stores,
+ whose value is not available readily, which we want to avoid. */
+ if (!pointer_set_contains (nontrap, lhs))
+ return false;
+
+ /* Now we've checked the constraints, so do the transformation:
+ 1) Remove the single store. */
+ gsi = gsi_for_stmt (assign);
+ unlink_stmt_vdef (assign);
+ gsi_remove (&gsi, true);
+ release_defs (assign);
+
+ /* 2) Create a temporary where we can store the old content
+ of the memory touched by the store, if we need to. */
+ if (!condstoretemp || TREE_TYPE (lhs) != TREE_TYPE (condstoretemp))
+ {
+ condstoretemp = create_tmp_reg (TREE_TYPE (lhs), "cstore");
+ get_var_ann (condstoretemp);
+ }
+ add_referenced_var (condstoretemp);
+
+ /* 3) Insert a load from the memory of the store to the temporary
+ on the edge which did not contain the store. */
+ lhs = unshare_expr (lhs);
+ new_stmt = gimple_build_assign (condstoretemp, lhs);
+ name = make_ssa_name (condstoretemp, new_stmt);
+ gimple_assign_set_lhs (new_stmt, name);
+ gimple_set_location (new_stmt, locus);
+ gsi_insert_on_edge (e1, new_stmt);
+
+ /* 4) Create a PHI node at the join block, with one argument
+ holding the old RHS, and the other holding the temporary
+ where we stored the old memory contents. */
+ newphi = create_phi_node (condstoretemp, join_bb);
+ add_phi_arg (newphi, rhs, e0, locus);
+ add_phi_arg (newphi, name, e1, locus);
+
+ lhs = unshare_expr (lhs);
+ new_stmt = gimple_build_assign (lhs, PHI_RESULT (newphi));
+
+ /* 5) Insert that PHI node. */
+ gsi = gsi_after_labels (join_bb);
+ if (gsi_end_p (gsi))
+ {
+ gsi = gsi_last_bb (join_bb);
+ gsi_insert_after (&gsi, new_stmt, GSI_NEW_STMT);
+ }
+ else
+ gsi_insert_before (&gsi, new_stmt, GSI_NEW_STMT);
+
+ return true;
+}
+
+/* Do the main work of conditional store replacement. */
+
+static bool
+cond_if_else_store_replacement_1 (basic_block then_bb, basic_block else_bb,
+ basic_block join_bb, gimple then_assign,
+ gimple else_assign)
+{
+ tree lhs_base, lhs, then_rhs, else_rhs;
+ source_location then_locus, else_locus;
+ gimple_stmt_iterator gsi;
+ gimple newphi, new_stmt;
+
+ if (then_assign == NULL
+ || !gimple_assign_single_p (then_assign)
+ || else_assign == NULL
+ || !gimple_assign_single_p (else_assign))
+ return false;
+
+ lhs = gimple_assign_lhs (then_assign);
+ if (!is_gimple_reg_type (TREE_TYPE (lhs))
+ || !operand_equal_p (lhs, gimple_assign_lhs (else_assign), 0))
+ return false;
+
+ lhs_base = get_base_address (lhs);
+ if (lhs_base == NULL_TREE
+ || (!DECL_P (lhs_base) && TREE_CODE (lhs_base) != MEM_REF))
+ return false;
+
+ then_rhs = gimple_assign_rhs1 (then_assign);
+ else_rhs = gimple_assign_rhs1 (else_assign);
+ then_locus = gimple_location (then_assign);
+ else_locus = gimple_location (else_assign);
+
+ /* Now we've checked the constraints, so do the transformation:
+ 1) Remove the stores. */
+ gsi = gsi_for_stmt (then_assign);
+ unlink_stmt_vdef (then_assign);
+ gsi_remove (&gsi, true);
+ release_defs (then_assign);
+
+ gsi = gsi_for_stmt (else_assign);
+ unlink_stmt_vdef (else_assign);
+ gsi_remove (&gsi, true);
+ release_defs (else_assign);
+
+ /* 2) Create a temporary where we can store the old content
+ of the memory touched by the store, if we need to. */
+ if (!condstoretemp || TREE_TYPE (lhs) != TREE_TYPE (condstoretemp))
+ {
+ condstoretemp = create_tmp_reg (TREE_TYPE (lhs), "cstore");
+ get_var_ann (condstoretemp);
+ }
+ add_referenced_var (condstoretemp);
+
+ /* 3) Create a PHI node at the join block, with one argument
+ holding the old RHS, and the other holding the temporary
+ where we stored the old memory contents. */
+ newphi = create_phi_node (condstoretemp, join_bb);
+ add_phi_arg (newphi, then_rhs, EDGE_SUCC (then_bb, 0), then_locus);
+ add_phi_arg (newphi, else_rhs, EDGE_SUCC (else_bb, 0), else_locus);
+
+ new_stmt = gimple_build_assign (lhs, PHI_RESULT (newphi));
+
+ /* 4) Insert that PHI node. */
+ gsi = gsi_after_labels (join_bb);
+ if (gsi_end_p (gsi))
+ {
+ gsi = gsi_last_bb (join_bb);
+ gsi_insert_after (&gsi, new_stmt, GSI_NEW_STMT);
+ }
+ else
+ gsi_insert_before (&gsi, new_stmt, GSI_NEW_STMT);
+
+ return true;
+}
+
+/* Conditional store replacement. We already know
+ that the recognized pattern looks like so:
+
+ split:
+ if (cond) goto THEN_BB; else goto ELSE_BB (edge E1)
+ THEN_BB:
+ ...
+ X = Y;
+ ...
+ goto JOIN_BB;
+ ELSE_BB:
+ ...
+ X = Z;
+ ...
+ fallthrough (edge E0)
+ JOIN_BB:
+ some more
+
+ We check that it is safe to sink the store to JOIN_BB by verifying that
+ there are no read-after-write or write-after-write dependencies in
+ THEN_BB and ELSE_BB. */
+
+static bool
+cond_if_else_store_replacement (basic_block then_bb, basic_block else_bb,
+ basic_block join_bb)
+{
+ gimple then_assign = last_and_only_stmt (then_bb);
+ gimple else_assign = last_and_only_stmt (else_bb);
+ VEC (data_reference_p, heap) *then_datarefs, *else_datarefs;
+ VEC (ddr_p, heap) *then_ddrs, *else_ddrs;
+ gimple then_store, else_store;
+ bool found, ok = false, res;
+ struct data_dependence_relation *ddr;
+ data_reference_p then_dr, else_dr;
+ int i, j;
+ tree then_lhs, else_lhs;
+ VEC (gimple, heap) *then_stores, *else_stores;
+ basic_block blocks[3];
+
+ if (MAX_STORES_TO_SINK == 0)
+ return false;
+
+ /* Handle the case with single statement in THEN_BB and ELSE_BB. */
+ if (then_assign && else_assign)
+ return cond_if_else_store_replacement_1 (then_bb, else_bb, join_bb,
+ then_assign, else_assign);
+
+ /* Find data references. */
+ then_datarefs = VEC_alloc (data_reference_p, heap, 1);
+ else_datarefs = VEC_alloc (data_reference_p, heap, 1);
+ if ((find_data_references_in_bb (NULL, then_bb, &then_datarefs)
+ == chrec_dont_know)
+ || !VEC_length (data_reference_p, then_datarefs)
+ || (find_data_references_in_bb (NULL, else_bb, &else_datarefs)
+ == chrec_dont_know)
+ || !VEC_length (data_reference_p, else_datarefs))
+ {
+ free_data_refs (then_datarefs);
+ free_data_refs (else_datarefs);
+ return false;
+ }
+
+ /* Find pairs of stores with equal LHS. */
+ then_stores = VEC_alloc (gimple, heap, 1);
+ else_stores = VEC_alloc (gimple, heap, 1);
+ FOR_EACH_VEC_ELT (data_reference_p, then_datarefs, i, then_dr)
+ {
+ if (DR_IS_READ (then_dr))
+ continue;
+
+ then_store = DR_STMT (then_dr);
+ then_lhs = gimple_assign_lhs (then_store);
+ found = false;
+
+ FOR_EACH_VEC_ELT (data_reference_p, else_datarefs, j, else_dr)
+ {
+ if (DR_IS_READ (else_dr))
+ continue;
+
+ else_store = DR_STMT (else_dr);
+ else_lhs = gimple_assign_lhs (else_store);
+
+ if (operand_equal_p (then_lhs, else_lhs, 0))
+ {
+ found = true;
+ break;
+ }
+ }
+
+ if (!found)
+ continue;
+
+ VEC_safe_push (gimple, heap, then_stores, then_store);
+ VEC_safe_push (gimple, heap, else_stores, else_store);
+ }
+
+ /* No pairs of stores found. */
+ if (!VEC_length (gimple, then_stores)
+ || VEC_length (gimple, then_stores) > (unsigned) MAX_STORES_TO_SINK)
+ {
+ free_data_refs (then_datarefs);
+ free_data_refs (else_datarefs);
+ VEC_free (gimple, heap, then_stores);
+ VEC_free (gimple, heap, else_stores);
+ return false;
+ }
+
+ /* Compute and check data dependencies in both basic blocks. */
+ then_ddrs = VEC_alloc (ddr_p, heap, 1);
+ else_ddrs = VEC_alloc (ddr_p, heap, 1);
+ compute_all_dependences (then_datarefs, &then_ddrs, NULL, false);
+ compute_all_dependences (else_datarefs, &else_ddrs, NULL, false);
+ blocks[0] = then_bb;
+ blocks[1] = else_bb;
+ blocks[2] = join_bb;
+ renumber_gimple_stmt_uids_in_blocks (blocks, 3);
+
+ /* Check that there are no read-after-write or write-after-write dependencies
+ in THEN_BB. */
+ FOR_EACH_VEC_ELT (ddr_p, then_ddrs, i, ddr)
+ {
+ struct data_reference *dra = DDR_A (ddr);
+ struct data_reference *drb = DDR_B (ddr);
+
+ if (DDR_ARE_DEPENDENT (ddr) != chrec_known
+ && ((DR_IS_READ (dra) && DR_IS_WRITE (drb)
+ && gimple_uid (DR_STMT (dra)) > gimple_uid (DR_STMT (drb)))
+ || (DR_IS_READ (drb) && DR_IS_WRITE (dra)
+ && gimple_uid (DR_STMT (drb)) > gimple_uid (DR_STMT (dra)))
+ || (DR_IS_WRITE (dra) && DR_IS_WRITE (drb))))
+ {
+ free_dependence_relations (then_ddrs);
+ free_dependence_relations (else_ddrs);
+ free_data_refs (then_datarefs);
+ free_data_refs (else_datarefs);
+ VEC_free (gimple, heap, then_stores);
+ VEC_free (gimple, heap, else_stores);
+ return false;
+ }
+ }
+
+ /* Check that there are no read-after-write or write-after-write dependencies
+ in ELSE_BB. */
+ FOR_EACH_VEC_ELT (ddr_p, else_ddrs, i, ddr)
+ {
+ struct data_reference *dra = DDR_A (ddr);
+ struct data_reference *drb = DDR_B (ddr);
+
+ if (DDR_ARE_DEPENDENT (ddr) != chrec_known
+ && ((DR_IS_READ (dra) && DR_IS_WRITE (drb)
+ && gimple_uid (DR_STMT (dra)) > gimple_uid (DR_STMT (drb)))
+ || (DR_IS_READ (drb) && DR_IS_WRITE (dra)
+ && gimple_uid (DR_STMT (drb)) > gimple_uid (DR_STMT (dra)))
+ || (DR_IS_WRITE (dra) && DR_IS_WRITE (drb))))
+ {
+ free_dependence_relations (then_ddrs);
+ free_dependence_relations (else_ddrs);
+ free_data_refs (then_datarefs);
+ free_data_refs (else_datarefs);
+ VEC_free (gimple, heap, then_stores);
+ VEC_free (gimple, heap, else_stores);
+ return false;
+ }
+ }
+
+ /* Sink stores with same LHS. */
+ FOR_EACH_VEC_ELT (gimple, then_stores, i, then_store)
+ {
+ else_store = VEC_index (gimple, else_stores, i);
+ res = cond_if_else_store_replacement_1 (then_bb, else_bb, join_bb,
+ then_store, else_store);
+ ok = ok || res;
+ }
+
+ free_dependence_relations (then_ddrs);
+ free_dependence_relations (else_ddrs);
+ free_data_refs (then_datarefs);
+ free_data_refs (else_datarefs);
+ VEC_free (gimple, heap, then_stores);
+ VEC_free (gimple, heap, else_stores);
+
+ return ok;
+}
/* Always do these optimizations if we have SSA
trees to work on. */
@@ -996,8 +1573,10 @@ gate_phiopt (void)
return 1;
}
-struct tree_opt_pass pass_phiopt =
+struct gimple_opt_pass pass_phiopt =
{
+ {
+ GIMPLE_PASS,
"phiopt", /* name */
gate_phiopt, /* gate */
tree_ssa_phiopt, /* execute */
@@ -1005,15 +1584,43 @@ struct tree_opt_pass pass_phiopt =
NULL, /* next */
0, /* static_pass_number */
TV_TREE_PHIOPT, /* tv_id */
- PROP_cfg | PROP_ssa | PROP_alias, /* properties_required */
+ PROP_cfg | PROP_ssa, /* properties_required */
+ 0, /* properties_provided */
+ 0, /* properties_destroyed */
+ 0, /* todo_flags_start */
+ TODO_dump_func
+ | TODO_ggc_collect
+ | TODO_verify_ssa
+ | TODO_verify_flow
+ | TODO_verify_stmts /* todo_flags_finish */
+ }
+};
+
+static bool
+gate_cselim (void)
+{
+ return flag_tree_cselim;
+}
+
+struct gimple_opt_pass pass_cselim =
+{
+ {
+ GIMPLE_PASS,
+ "cselim", /* name */
+ gate_cselim, /* gate */
+ tree_ssa_cs_elim, /* execute */
+ NULL, /* sub */
+ NULL, /* next */
+ 0, /* static_pass_number */
+ TV_TREE_PHIOPT, /* tv_id */
+ PROP_cfg | PROP_ssa, /* properties_required */
0, /* properties_provided */
0, /* properties_destroyed */
0, /* todo_flags_start */
- TODO_cleanup_cfg
- | TODO_dump_func
+ TODO_dump_func
| TODO_ggc_collect
| TODO_verify_ssa
| TODO_verify_flow
- | TODO_verify_stmts, /* todo_flags_finish */
- 0 /* letter */
+ | TODO_verify_stmts /* todo_flags_finish */
+ }
};