/* Optimization of PHI nodes by converting them into straightline code.
- Copyright (C) 2004, 2005, 2006, 2007, 2008 Free Software Foundation,
- Inc.
+ Copyright (C) 2004, 2005, 2006, 2007, 2008, 2009, 2010
+ Free Software Foundation, Inc.
This file is part of GCC.
#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 "pointer-set.h"
#include "domwalk.h"
+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);
+ 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, tree, tree);
+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
bb0:
if (cond) goto bb2; else goto bb1;
bb1:
- *p = RHS
+ *p = RHS;
bb2:
with
condtmp' = *p;
bb2:
condtmp = PHI <RHS, condtmp'>
- *p = condtmp
+ *p = condtmp;
This transformation can only be done under several constraints,
- documented below. */
+ 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 <RHS1, RHS2>
+ *p = condtmp; */
static unsigned int
tree_ssa_cs_elim (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);
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);
}
else
{
- phi = phi_nodes (bb2);
+ gimple_seq phis = 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)
+ if (! gimple_seq_singleton_p (phis))
continue;
- arg0 = PHI_ARG_DEF_TREE (phi, e1->dest_idx);
- arg1 = PHI_ARG_DEF_TREE (phi, e2->dest_idx);
+ phi = gsi_stmt (gsi_start (phis));
+ 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. */
}
free (bb_order);
-
+
if (do_store_elim)
pointer_set_destroy (nontrap);
/* If the CFG has changed, we should cleanup the CFG. */
{
/* In cond-store replacement we have added some loads on edges
and new VOPS (as we moved the store, and created a load). */
- bsi_commit_edge_inserts ();
+ gsi_commit_edge_inserts ();
return TODO_cleanup_cfg | TODO_update_ssa_only_virtuals;
}
else if (cfgchanged)
{
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);
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.
static void
replace_phi_edge_with_variable (basic_block cond_block,
- edge e, tree phi, tree new_tree)
+ 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_tree);
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,
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_stmt, 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
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
- && !useless_type_conversion_p (TREE_TYPE (result), TREE_TYPE (cond)))
- {
- tree tmp;
-
- if (!COMPARISON_CLASS_P (cond))
- return false;
-
- tmp = create_tmp_var (TREE_TYPE (cond), NULL);
- add_referenced_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 (!useless_type_conversion_p (TREE_TYPE (result), TREE_TYPE (cond)))
- 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 = build_gimple_modify_stmt (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.
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_stmt = build_gimple_modify_stmt (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;
- }
- /* 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;
- }
+ stmt = last_stmt (cond_bb);
+ result = PHI_RESULT (phi);
- /* 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 (CONVERT_EXPR_P (cond));
-
- op0 = TREE_OPERAND (cond, 0);
- tmp = create_tmp_var (TREE_TYPE (op0), NULL);
- add_referenced_var (tmp);
- cond_tmp = make_ssa_name (tmp, NULL);
- new_stmt = build_gimple_modify_stmt (cond_tmp, op0);
- SSA_NAME_DEF_STMT (cond_tmp) = new_stmt;
-
- bsi_insert_after (&bsi, new_stmt, BSI_NEW_STMT);
- cond = fold_convert (TREE_TYPE (result), cond_tmp);
- }
+ /* 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));
- new_stmt = build_gimple_modify_stmt (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_stmt, BSI_NEW_STMT);
-
- SSA_NAME_DEF_STMT (new_var1) = new_stmt;
-
- 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;
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. */
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
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;
/* 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
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_stmt;
+ 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));
if (HONOR_NANS (TYPE_MODE (type)))
return false;
- cond = COND_EXPR_COND (last_stmt (cond_bb));
- cmp = TREE_CODE (cond);
+ cond = last_stmt (cond_bb);
+ cmp = gimple_cond_code (cond);
result = PHI_RESULT (phi);
/* 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;
&& operand_equal_for_phi_arg_p (arg_false, larger))
{
/* Case
-
+
if (smaller < larger)
rslt = smaller;
else
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) != GIMPLE_MODIFY_STMT)
+ || gimple_code (assign) != GIMPLE_ASSIGN)
return false;
- lhs = GIMPLE_STMT_OPERAND (assign, 0);
- rhs = GIMPLE_STMT_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)
{
}
/* 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_stmt = build_gimple_modify_stmt (result, build2 (minmax, type, arg0, arg1));
- SSA_NAME_DEF_STMT (result) = new_stmt;
- bsi = bsi_last (cond_bb);
- bsi_insert_before (&bsi, new_stmt, 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;
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_stmt, 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;
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) != GIMPLE_MODIFY_STMT)
+ if (gimple_code (assign) != GIMPLE_ASSIGN)
return false;
- lhs = GIMPLE_STMT_OPERAND (assign, 0);
- rhs = GIMPLE_STMT_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;
lhs = result;
/* Build the modify expression with abs expression. */
- new_stmt = build_gimple_modify_stmt (lhs,
- build1 (ABS_EXPR, TREE_TYPE (lhs), rhs));
- SSA_NAME_DEF_STMT (lhs) = new_stmt;
+ new_stmt = gimple_build_assign_with_ops (ABS_EXPR, lhs, rhs, NULL);
- bsi = bsi_last (cond_bb);
- bsi_insert_before (&bsi, new_stmt, 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_stmt = build_gimple_modify_stmt (result,
- build1 (NEGATE_EXPR, TREE_TYPE (lhs),
- lhs));
- SSA_NAME_DEF_STMT (result) = new_stmt;
+ new_stmt = gimple_build_assign_with_ops (NEGATE_EXPR, result, lhs, NULL);
- bsi_insert_after (&bsi, new_stmt, BSI_NEW_STMT);
+ gsi_insert_after (&gsi, new_stmt, GSI_NEW_STMT);
}
replace_phi_edge_with_variable (cond_bb, e1, phi, result);
/* 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 INDIRECT_REFs, so we only need to track
+ 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 INDIRECT_REF we determine if we've already seen a same
+ 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
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 INDIRECT_REF
+/* 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
/* The hash table for remembering what we've seen. */
static htab_t seen_ssa_names;
-/* The set of INDIRECT_REFs which can't trap. */
+/* 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. */
}
/* We see the expression EXP in basic block BB. If it's an interesting
- expression (an INDIRECT_REF through an SSA_NAME) possibly insert the
+ 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. */
add_or_mark_expr (basic_block bb, tree exp,
struct pointer_set_t *nontrap, bool store)
{
- if (INDIRECT_REF_P (exp)
+ if (TREE_CODE (exp) == MEM_REF
&& TREE_CODE (TREE_OPERAND (exp, 0)) == SSA_NAME)
{
tree name = TREE_OPERAND (exp, 0);
struct name_to_bb *n2bb;
basic_block found_bb = 0;
- /* Try to find the last seen INDIRECT_REF through the same
+ /* Try to find the last seen MEM_REF through the same
SSA_NAME, which can trap. */
map.ssa_name = name;
map.bb = 0;
if (n2bb)
found_bb = n2bb->bb;
- /* If we've found a trapping INDIRECT_REF, _and_ it dominates EXP
+ /* 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)
static void
nt_init_block (struct dom_walk_data *data ATTRIBUTE_UNUSED, basic_block bb)
{
- block_stmt_iterator bsi;
+ 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 (bsi = bsi_start (bb); !bsi_end_p (bsi); bsi_next (&bsi))
+ for (gsi = gsi_start_bb (bb); !gsi_end_p (gsi); gsi_next (&gsi))
{
- tree stmt = bsi_stmt (bsi);
+ gimple stmt = gsi_stmt (gsi);
- if (TREE_CODE (stmt) == GIMPLE_MODIFY_STMT)
+ if (is_gimple_assign (stmt))
{
- tree lhs = GIMPLE_STMT_OPERAND (stmt, 0);
- tree rhs = GIMPLE_STMT_OPERAND (stmt, 1);
- add_or_mark_expr (bb, rhs, nontrap_set, false);
- add_or_mark_expr (bb, lhs, nontrap_set, true);
+ 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);
}
}
}
/* 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 INDIRECT_REFs itself) which can't trap. */
+ (the MEM_REFs itself) which can't trap. */
static struct pointer_set_t *
get_non_trapping (void)
{
/* Setup callbacks for the generic dominator tree walker. */
nontrap_set = nontrap;
- walk_data.walk_stmts_backward = false;
walk_data.dom_direction = CDI_DOMINATORS;
walk_data.initialize_block_local_data = NULL;
- walk_data.before_dom_children_before_stmts = nt_init_block;
- walk_data.before_dom_children_walk_stmts = NULL;
- walk_data.before_dom_children_after_stmts = NULL;
- walk_data.after_dom_children_before_stmts = NULL;
- walk_data.after_dom_children_walk_stmts = NULL;
- walk_data.after_dom_children_after_stmts = nt_fini_block;
+ 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;
- walk_data.interesting_blocks = NULL;
init_walk_dominator_tree (&walk_data);
walk_dominator_tree (&walk_data, ENTRY_BLOCK_PTR);
cond_store_replacement (basic_block middle_bb, basic_block join_bb,
edge e0, edge e1, struct pointer_set_t *nontrap)
{
- tree assign = last_and_only_stmt (middle_bb);
- tree lhs, rhs, newexpr, name;
- tree newphi;
- block_stmt_iterator bsi;
+ 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
- || TREE_CODE (assign) != GIMPLE_MODIFY_STMT)
+ || !gimple_assign_single_p (assign))
return false;
- lhs = GIMPLE_STMT_OPERAND (assign, 0);
- if (!INDIRECT_REF_P (lhs))
- return false;
- rhs = GIMPLE_STMT_OPERAND (assign, 1);
- if (TREE_CODE (rhs) != SSA_NAME && !is_gimple_min_invariant (rhs))
+ 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. */
/* Now we've checked the constraints, so do the transformation:
1) Remove the single store. */
- mark_symbols_for_renaming (assign);
- bsi = bsi_for_stmt (assign);
- bsi_remove (&bsi, true);
+ 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_var (TREE_TYPE (lhs), "cstore");
+ condstoretemp = create_tmp_reg (TREE_TYPE (lhs), "cstore");
get_var_ann (condstoretemp);
- if (TREE_CODE (TREE_TYPE (lhs)) == COMPLEX_TYPE
- || TREE_CODE (TREE_TYPE (lhs)) == VECTOR_TYPE)
- DECL_GIMPLE_REG_P (condstoretemp) = 1;
}
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);
- newexpr = build_gimple_modify_stmt (condstoretemp, lhs);
- name = make_ssa_name (condstoretemp, newexpr);
- GIMPLE_STMT_OPERAND (newexpr, 0) = name;
- mark_symbols_for_renaming (newexpr);
- bsi_insert_on_edge (e1, newexpr);
+ 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);
- add_phi_arg (newphi, name, e1);
+ add_phi_arg (newphi, rhs, e0, locus);
+ add_phi_arg (newphi, name, e1, locus);
lhs = unshare_expr (lhs);
- newexpr = build_gimple_modify_stmt (lhs, PHI_RESULT (newphi));
- mark_symbols_for_renaming (newexpr);
+ new_stmt = gimple_build_assign (lhs, PHI_RESULT (newphi));
/* 5) Insert that PHI node. */
- bsi = bsi_start (join_bb);
- while (!bsi_end_p (bsi) && TREE_CODE (bsi_stmt (bsi)) == LABEL_EXPR)
- bsi_next (&bsi);
- if (bsi_end_p (bsi))
+ 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. 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 THEN_BB and ELSE_BB contain only one store
+ that the stores have a "simple" RHS. */
+
+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);
+ tree lhs_base, lhs, then_rhs, else_rhs;
+ source_location then_locus, else_locus;
+ gimple_stmt_iterator gsi;
+ gimple newphi, new_stmt;
+
+ /* Check if then_bb and else_bb contain only one store each. */
+ 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))
{
- bsi = bsi_last (join_bb);
- bsi_insert_after (&bsi, newexpr, BSI_NEW_STMT);
+ gsi = gsi_last_bb (join_bb);
+ gsi_insert_after (&gsi, new_stmt, GSI_NEW_STMT);
}
else
- bsi_insert_before (&bsi, newexpr, BSI_NEW_STMT);
+ gsi_insert_before (&gsi, new_stmt, GSI_NEW_STMT);
return true;
}
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 */
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 */
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