From: Andrew Pinski <apin...@marvell.com>
This PR was orignally for the missed optimization of a few isnegative which
had been solved a long time ago (sometime before 4.4.0). I noticed there was
one missed optimization on the gimple level. There is a match.pd pattern
for ~a < CST but we miss that there could be a nop_convert between the the
comparison and the bit_not. This adds the optional option cast to the current
match.pd pattern.
OK? Bootstrapped and tested on x86_64 with no regressions.
PR tree-optimization/31531
gcc/ChangeLog:
* match.pd (~X op C): Allow for an optional nop convert.
gcc/testsuite/ChangeLog:
* gcc.dg/tree-ssa/pr31531-1.c: New test.
---
gcc/match.pd | 5 +++--
gcc/testsuite/gcc.dg/tree-ssa/pr31531-1.c | 19 +++++++++++++++++++
2 files changed, 22 insertions(+), 2 deletions(-)
create mode 100644 gcc/testsuite/gcc.dg/tree-ssa/pr31531-1.c
diff --git a/gcc/match.pd b/gcc/match.pd
index 37c5be9e5f4..ca6c9eff624 100644
--- a/gcc/match.pd
+++ b/gcc/match.pd
@@ -4729,10 +4729,11 @@ DEFINE_INT_AND_FLOAT_ROUND_FN (RINT)
(for cmp (simple_comparison)
scmp (swapped_simple_comparison)
(simplify
- (cmp (bit_not@2 @0) CONSTANT_CLASS_P@1)
+ (cmp (nop_convert?:s (bit_not@2 @0)) CONSTANT_CLASS_P@1)
(if (single_use (@2)
&& (TREE_CODE (@1) == INTEGER_CST || TREE_CODE (@1) == VECTOR_CST))
- (scmp @0 (bit_not @1)))))
+ (with { tree type1 = TREE_TYPE (@1); }
+ (scmp (convert:type1 @0) (bit_not @1))))))
(for cmp (simple_comparison)
/* Fold (double)float1 CMP (double)float2 into float1 CMP float2. */
diff --git a/gcc/testsuite/gcc.dg/tree-ssa/pr31531-1.c
b/gcc/testsuite/gcc.dg/tree-ssa/pr31531-1.c
new file mode 100644
index 00000000000..c27299151eb
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/tree-ssa/pr31531-1.c
@@ -0,0 +1,19 @@
+/* { dg-do compile } */
+/* { dg-options "-O2 -fdump-tree-optimized" } */
+/* PR tree-optimization/31531 */
+
+int f(int a)
+{
+ int b = ~a;
+ return b<0;
+}
+
+
+int f1(unsigned a)
+{
+ int b = ~a;
+ return b<0;
+}
+/* We should convert the above two functions from b <0 to ((int)a) >= 0. */
+/* { dg-final { scan-tree-dump-times ">= 0" 2 "optimized"} } */
+/* { dg-final { scan-tree-dump-times "~" 0 "optimized"} } */
--
2.17.1
