From a34519735694f005b45a5ec04d33fa8a20e2071c Mon Sep 17 00:00:00 2001
From: kazu <kazu@138bc75d-0d04-0410-961f-82ee72b054a4>
Date: Fri, 15 Apr 2005 18:42:38 +0000
Subject: [PATCH] gcc/ PR tree-optimization/21031 * tree-ssa-forwprop.c
(ssa_name_defined_by_comparison_p): New.
(forward_propagate_into_cond_1): Call it. Forward propagate
integer-integer casts into COND_EXPRs.
testsuite/
PR tree-optimization/21031
* gcc.dg/tree-ssa/pr21031.c: New.
git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@98199 138bc75d-0d04-0410-961f-82ee72b054a4
---
gcc/ChangeLog | 7 +++++++
gcc/testsuite/ChangeLog | 5 +++++
gcc/testsuite/gcc.dg/tree-ssa/pr21031.c | 20 ++++++++++++++++++++
gcc/tree-ssa-forwprop.c | 23 +++++++++++++++++++++++
4 files changed, 55 insertions(+)
create mode 100644 gcc/testsuite/gcc.dg/tree-ssa/pr21031.c
diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index f1757895d318..2c6aa4331ecd 100644
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,3 +1,10 @@
+2005-04-15 Kazu Hirata <kazu@cs.umass.edu>
+
+ PR tree-optimization/21031
+ * tree-ssa-forwprop.c (ssa_name_defined_by_comparison_p): New.
+ (forward_propagate_into_cond_1): Call it. Forward propagate
+ integer-integer casts into COND_EXPRs.
+
2005-04-15 Dave Korn <dave.korn@artimi.com>
* gcc.c (default_compilers): Clarify obscure error message when
diff --git a/gcc/testsuite/ChangeLog b/gcc/testsuite/ChangeLog
index b2b8e9798e1d..41a3508a90c5 100644
--- a/gcc/testsuite/ChangeLog
+++ b/gcc/testsuite/ChangeLog
@@ -1,3 +1,8 @@
+2005-04-15 Kazu Hirata <kazu@cs.umass.edu>
+
+ PR tree-optimization/21031
+ * gcc.dg/tree-ssa/pr21031.c: New.
+
2005-04-15 Uros Bizjak <uros@kss-loka.si>
PR tree-optimization/21004
diff --git a/gcc/testsuite/gcc.dg/tree-ssa/pr21031.c b/gcc/testsuite/gcc.dg/tree-ssa/pr21031.c
new file mode 100644
index 000000000000..df200d564d34
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/tree-ssa/pr21031.c
@@ -0,0 +1,20 @@
+/* PR tree-optimization/21031
+
+ Make sure that a != 0 is propagated into the "if" statement. */
+
+/* { dg-do compile } */
+/* { dg-options "-O1 -fdump-tree-forwprop1-details" } */
+
+int
+foo (int a)
+{
+ int b = a != 0;
+ unsigned char c = b;
+ if (c)
+ return 1;
+ else
+ return 0;
+}
+
+/* { dg-final { scan-tree-dump-times "Replaced" 2 "forwprop1"} } */
+/* { dg-final { cleanup-tree-dump "forwprop1" } } */
diff --git a/gcc/tree-ssa-forwprop.c b/gcc/tree-ssa-forwprop.c
index 75fe6e17c764..a47d69ae7cc5 100644
--- a/gcc/tree-ssa-forwprop.c
+++ b/gcc/tree-ssa-forwprop.c
@@ -109,6 +109,23 @@ Boston, MA 02111-1307, USA. */
This will (of course) be extended as other needs arise. */
+/* Given an SSA_NAME VAR, return true if and only if VAR is defined by
+ a comparison. */
+
+static bool
+ssa_name_defined_by_comparison_p (tree var)
+{
+ tree def = SSA_NAME_DEF_STMT (var);
+
+ if (TREE_CODE (def) == MODIFY_EXPR)
+ {
+ tree rhs = TREE_OPERAND (def, 1);
+ return COMPARISON_CLASS_P (rhs);
+ }
+
+ return 0;
+}
+
/* Forward propagate a single-use variable into COND once. Return a
new condition if successful. Return NULL_TREE otherwise. */
@@ -303,6 +320,12 @@ forward_propagate_into_cond_1 (tree cond, tree *test_var_p)
|| (TREE_CODE (inner_type) == BOOLEAN_TYPE
&& INTEGRAL_TYPE_P (outer_type)))
;
+ else if (INTEGRAL_TYPE_P (outer_type)
+ && INTEGRAL_TYPE_P (inner_type)
+ && TREE_CODE (TREE_OPERAND (def_rhs, 0)) == SSA_NAME
+ && ssa_name_defined_by_comparison_p (TREE_OPERAND (def_rhs,
+ 0)))
+ ;
else
return NULL_TREE;
--
GitLab