From d2d8936f3faf747a3305f39bc4d12a37fbe3e8cb Mon Sep 17 00:00:00 2001
From: Jeff Law <law@redhat.com>
Date: Thu, 24 Jun 2004 09:59:52 -0600
Subject: [PATCH] tree-ssa-dom.c (record_dominating_conditions): New function.
* tree-ssa-dom.c (record_dominating_conditions): New function.
(dom_opt_finalize_block, get_eq_expr_value): Use it.
* gcc.dg/tree-ssa/20040624-1.c: New test.
From-SVN: r83597
---
gcc/ChangeLog | 5 +
gcc/testsuite/ChangeLog | 4 +
gcc/testsuite/gcc.dg/tree-ssa/20040624-1.c | 21 +++
gcc/tree-ssa-dom.c | 177 +++++++++++++++++++++
4 files changed, 207 insertions(+)
create mode 100644 gcc/testsuite/gcc.dg/tree-ssa/20040624-1.c
diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index d50d7f061b5d..9876fc878ae1 100644
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,3 +1,8 @@
+2004-06-24 Jeff Law <law@redhat.com>
+
+ * tree-ssa-dom.c (record_dominating_conditions): New function.
+ (dom_opt_finalize_block, get_eq_expr_value): Use it.
+
2004-06-24 Richard Sandiford <rsandifo@redhat.com>
* calls.c (shift_returned_value): Fix handling of non-integer
diff --git a/gcc/testsuite/ChangeLog b/gcc/testsuite/ChangeLog
index 07f99b51338b..f7acf36ee0b5 100644
--- a/gcc/testsuite/ChangeLog
+++ b/gcc/testsuite/ChangeLog
@@ -1,3 +1,7 @@
+2004-06-24 Jeff Law <law@redhat.com>
+
+ * gcc.dg/tree-ssa/20040624-1.c: New test.
+
2004-06-24 Richard Sandiford <rsandifo@redhat.com>
* gcc.c-torture/compile/20040624-1.c: New test.
diff --git a/gcc/testsuite/gcc.dg/tree-ssa/20040624-1.c b/gcc/testsuite/gcc.dg/tree-ssa/20040624-1.c
new file mode 100644
index 000000000000..54f37433d95f
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/tree-ssa/20040624-1.c
@@ -0,0 +1,21 @@
+/* { dg-do compile } */
+/* { dg-options "-O1 -fdump-tree-dom1" } */
+
+void bar1 (void);
+void bar2 (void);
+
+void
+foo (unsigned int a, unsigned int b)
+{
+ if (a >= b)
+ bar1 ();
+ else if (a <= b)
+ bar2 ();
+}
+
+/* The second conditional is redundant since we know it must be
+ true (to reach the second condition we know a < b via the first
+ conditional. */
+
+/* { dg-final { scan-tree-dump-times "if " 1 "dom1" } } */
+
diff --git a/gcc/tree-ssa-dom.c b/gcc/tree-ssa-dom.c
index 2be24ae1c8d9..a4151423cf36 100644
--- a/gcc/tree-ssa-dom.c
+++ b/gcc/tree-ssa-dom.c
@@ -226,6 +226,7 @@ static hashval_t avail_expr_hash (const void *);
static int avail_expr_eq (const void *, const void *);
static void htab_statistics (FILE *, htab_t);
static void record_cond (tree, tree, varray_type *);
+static void record_dominating_conditions (tree, varray_type *);
static void record_const_or_copy (tree, tree, varray_type *);
static void record_equality (tree, tree, varray_type *);
static tree update_rhs_and_lookup_avail_expr (tree, tree, varray_type *,
@@ -1228,6 +1229,7 @@ dom_opt_finalize_block (struct dom_walk_data *walk_data, basic_block bb)
if (TREE_CODE_CLASS (cond_code) == '<')
{
record_cond (cond, boolean_true_node, &bd->avail_exprs);
+ record_dominating_conditions (cond, &bd->avail_exprs);
record_cond (inverted, boolean_false_node, &bd->avail_exprs);
}
else if (cond_code == SSA_NAME)
@@ -1257,6 +1259,7 @@ dom_opt_finalize_block (struct dom_walk_data *walk_data, basic_block bb)
{
record_cond (cond, boolean_false_node, &bd->avail_exprs);
record_cond (inverted, boolean_true_node, &bd->avail_exprs);
+ record_dominating_conditions (inverted, &bd->avail_exprs);
}
else if (cond_code == SSA_NAME)
record_const_or_copy (cond, boolean_false_node,
@@ -1606,6 +1609,178 @@ record_cond (tree cond, tree value, varray_type *block_avail_exprs_p)
free (element);
}
+/* COND is a condition which is known to be true. Record variants of
+ COND which must also be true.
+
+ For example, if a < b is true, then a <= b must also be true. */
+
+static void
+record_dominating_conditions (tree cond, varray_type *block_avail_exprs_p)
+{
+ switch (TREE_CODE (cond))
+ {
+ case LT_EXPR:
+ record_cond (build2 (LE_EXPR, boolean_type_node,
+ TREE_OPERAND (cond, 0),
+ TREE_OPERAND (cond, 1)),
+ boolean_true_node,
+ block_avail_exprs_p);
+ record_cond (build2 (ORDERED_EXPR, boolean_type_node,
+ TREE_OPERAND (cond, 0),
+ TREE_OPERAND (cond, 1)),
+ boolean_true_node,
+ block_avail_exprs_p);
+ record_cond (build2 (NE_EXPR, boolean_type_node,
+ TREE_OPERAND (cond, 0),
+ TREE_OPERAND (cond, 1)),
+ boolean_true_node,
+ block_avail_exprs_p);
+ record_cond (build2 (LTGT_EXPR, boolean_type_node,
+ TREE_OPERAND (cond, 0),
+ TREE_OPERAND (cond, 1)),
+ boolean_true_node,
+ block_avail_exprs_p);
+ break;
+
+ case GT_EXPR:
+ record_cond (build2 (GE_EXPR, boolean_type_node,
+ TREE_OPERAND (cond, 0),
+ TREE_OPERAND (cond, 1)),
+ boolean_true_node,
+ block_avail_exprs_p);
+ record_cond (build2 (ORDERED_EXPR, boolean_type_node,
+ TREE_OPERAND (cond, 0),
+ TREE_OPERAND (cond, 1)),
+ boolean_true_node,
+ block_avail_exprs_p);
+ record_cond (build2 (NE_EXPR, boolean_type_node,
+ TREE_OPERAND (cond, 0),
+ TREE_OPERAND (cond, 1)),
+ boolean_true_node,
+ block_avail_exprs_p);
+ record_cond (build2 (LTGT_EXPR, boolean_type_node,
+ TREE_OPERAND (cond, 0),
+ TREE_OPERAND (cond, 1)),
+ boolean_true_node,
+ block_avail_exprs_p);
+ break;
+
+ case GE_EXPR:
+ case LE_EXPR:
+ record_cond (build2 (ORDERED_EXPR, boolean_type_node,
+ TREE_OPERAND (cond, 0),
+ TREE_OPERAND (cond, 1)),
+ boolean_true_node,
+ block_avail_exprs_p);
+ break;
+
+ case EQ_EXPR:
+ record_cond (build2 (ORDERED_EXPR, boolean_type_node,
+ TREE_OPERAND (cond, 0),
+ TREE_OPERAND (cond, 1)),
+ boolean_true_node,
+ block_avail_exprs_p);
+ record_cond (build2 (LE_EXPR, boolean_type_node,
+ TREE_OPERAND (cond, 0),
+ TREE_OPERAND (cond, 1)),
+ boolean_true_node,
+ block_avail_exprs_p);
+ record_cond (build2 (GE_EXPR, boolean_type_node,
+ TREE_OPERAND (cond, 0),
+ TREE_OPERAND (cond, 1)),
+ boolean_true_node,
+ block_avail_exprs_p);
+ break;
+
+ case UNORDERED_EXPR:
+ record_cond (build2 (NE_EXPR, boolean_type_node,
+ TREE_OPERAND (cond, 0),
+ TREE_OPERAND (cond, 1)),
+ boolean_true_node,
+ block_avail_exprs_p);
+ record_cond (build2 (UNLE_EXPR, boolean_type_node,
+ TREE_OPERAND (cond, 0),
+ TREE_OPERAND (cond, 1)),
+ boolean_true_node,
+ block_avail_exprs_p);
+ record_cond (build2 (UNGE_EXPR, boolean_type_node,
+ TREE_OPERAND (cond, 0),
+ TREE_OPERAND (cond, 1)),
+ boolean_true_node,
+ block_avail_exprs_p);
+ record_cond (build2 (UNEQ_EXPR, boolean_type_node,
+ TREE_OPERAND (cond, 0),
+ TREE_OPERAND (cond, 1)),
+ boolean_true_node,
+ block_avail_exprs_p);
+ record_cond (build2 (UNLT_EXPR, boolean_type_node,
+ TREE_OPERAND (cond, 0),
+ TREE_OPERAND (cond, 1)),
+ boolean_true_node,
+ block_avail_exprs_p);
+ record_cond (build2 (UNGT_EXPR, boolean_type_node,
+ TREE_OPERAND (cond, 0),
+ TREE_OPERAND (cond, 1)),
+ boolean_true_node,
+ block_avail_exprs_p);
+ break;
+
+ case UNLT_EXPR:
+ record_cond (build2 (UNLE_EXPR, boolean_type_node,
+ TREE_OPERAND (cond, 0),
+ TREE_OPERAND (cond, 1)),
+ boolean_true_node,
+ block_avail_exprs_p);
+ record_cond (build2 (NE_EXPR, boolean_type_node,
+ TREE_OPERAND (cond, 0),
+ TREE_OPERAND (cond, 1)),
+ boolean_true_node,
+ block_avail_exprs_p);
+ break;
+
+ case UNGT_EXPR:
+ record_cond (build2 (UNGE_EXPR, boolean_type_node,
+ TREE_OPERAND (cond, 0),
+ TREE_OPERAND (cond, 1)),
+ boolean_true_node,
+ block_avail_exprs_p);
+ record_cond (build2 (NE_EXPR, boolean_type_node,
+ TREE_OPERAND (cond, 0),
+ TREE_OPERAND (cond, 1)),
+ boolean_true_node,
+ block_avail_exprs_p);
+ break;
+
+ case UNEQ_EXPR:
+ record_cond (build2 (UNLE_EXPR, boolean_type_node,
+ TREE_OPERAND (cond, 0),
+ TREE_OPERAND (cond, 1)),
+ boolean_true_node,
+ block_avail_exprs_p);
+ record_cond (build2 (UNGE_EXPR, boolean_type_node,
+ TREE_OPERAND (cond, 0),
+ TREE_OPERAND (cond, 1)),
+ boolean_true_node,
+ block_avail_exprs_p);
+ break;
+
+ case LTGT_EXPR:
+ record_cond (build2 (NE_EXPR, boolean_type_node,
+ TREE_OPERAND (cond, 0),
+ TREE_OPERAND (cond, 1)),
+ boolean_true_node,
+ block_avail_exprs_p);
+ record_cond (build2 (ORDERED_EXPR, boolean_type_node,
+ TREE_OPERAND (cond, 0),
+ TREE_OPERAND (cond, 1)),
+ boolean_true_node,
+ block_avail_exprs_p);
+
+ default:
+ break;
+ }
+}
+
/* A helper function for record_const_or_copy and record_equality.
Do the work of recording the value and undo info. */
@@ -3044,6 +3219,7 @@ get_eq_expr_value (tree if_stmt,
if (true_arm)
{
record_cond (cond, boolean_true_node, block_avail_exprs_p);
+ record_dominating_conditions (cond, block_avail_exprs_p);
record_cond (inverted, boolean_false_node, block_avail_exprs_p);
if (TREE_CONSTANT (op1))
@@ -3062,6 +3238,7 @@ get_eq_expr_value (tree if_stmt,
{
record_cond (inverted, boolean_true_node, block_avail_exprs_p);
+ record_dominating_conditions (inverted, block_avail_exprs_p);
record_cond (cond, boolean_false_node, block_avail_exprs_p);
if (TREE_CONSTANT (op1))
--
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