This patch simplify `(trunc)copysign ((extend)x, CST)` to `copysign (x,
-1.0/1.0)`
depending on the sign of CST. Previously, it was simplified to `copysign (x,
CST)`.
It can be optimized as the sign of the CST matters, not the value.
The patch also simplify `(trunc)abs (extend x)` to `abs (x)`.
PR tree-optimization/112472
gcc/ChangeLog:
* match.pd ((trunc)copysign ((extend)x, -CST) --> copysign (x, -1.0)):
New pattern.
((trunc)abs (extend x) --> abs (x)): New pattern.
gcc/testsuite/ChangeLog:
* gcc.dg/tree-ssa/pr112472.c: New test.
Signed-off-by: Eikansh Gupta <[email protected]>
---
gcc/match.pd | 25 +++++++++++++++++++-----
gcc/testsuite/gcc.dg/tree-ssa/pr112472.c | 22 +++++++++++++++++++++
2 files changed, 42 insertions(+), 5 deletions(-)
create mode 100644 gcc/testsuite/gcc.dg/tree-ssa/pr112472.c
diff --git a/gcc/match.pd b/gcc/match.pd
index 00988241348..5b930beb418 100644
--- a/gcc/match.pd
+++ b/gcc/match.pd
@@ -8854,19 +8854,34 @@ DEFINE_INT_AND_FLOAT_ROUND_FN (RINT)
type, OPTIMIZE_FOR_BOTH))
(tos @0))))
-/* Simplify (trunc)copysign ((extend)x, (extend)y) to copysignf (x, y),
- x,y is float value, similar for _Float16/double. */
+/* Simplify (trunc)copysign ((extend)x, (extend)y) to copysignf (x, y) and
+ simplify (trunc)copysign ((extend)x, CST) to copysign (x, -1.0/1.0).
+ x,y is float value, similar for _Float16/double. */
(for copysigns (COPYSIGN_ALL)
(simplify
- (convert (copysigns (convert@2 @0) (convert @1)))
+ (convert (copysigns (convert@2 @0) (convert2? @1)))
(if (optimize
&& !HONOR_SNANS (@2)
&& types_match (type, TREE_TYPE (@0))
- && types_match (type, TREE_TYPE (@1))
&& TYPE_PRECISION (type) < TYPE_PRECISION (TREE_TYPE (@2))
&& direct_internal_fn_supported_p (IFN_COPYSIGN,
type, OPTIMIZE_FOR_BOTH))
- (IFN_COPYSIGN @0 @1))))
+ (if (TREE_CODE (@1) == REAL_CST)
+ (if (REAL_VALUE_NEGATIVE (TREE_REAL_CST (@1)))
+ (IFN_COPYSIGN @0 { build_minus_one_cst (type); })
+ (IFN_COPYSIGN @0 { build_one_cst (type); }))
+ (if (types_match (type, TREE_TYPE (@1)))
+ (IFN_COPYSIGN @0 @1))))))
+
+/* (trunc)abs (extend x) --> abs (x)
+ x is a float value */
+(simplify
+ (convert (abs (convert@1 @0)))
+ (if (optimize
+ && !HONOR_SNANS (@1)
+ && types_match (type, TREE_TYPE (@0))
+ && TYPE_PRECISION (type) < TYPE_PRECISION (TREE_TYPE (@1)))
+ (abs @0)))
(for froms (BUILT_IN_FMAF BUILT_IN_FMA BUILT_IN_FMAL)
tos (IFN_FMA IFN_FMA IFN_FMA)
diff --git a/gcc/testsuite/gcc.dg/tree-ssa/pr112472.c
b/gcc/testsuite/gcc.dg/tree-ssa/pr112472.c
new file mode 100644
index 00000000000..8f97278ffe8
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/tree-ssa/pr112472.c
@@ -0,0 +1,22 @@
+/* PR tree-optimization/109878 */
+/* { dg-do compile } */
+/* { dg-options "-O1 -fdump-tree-optimized" } */
+
+/* Optimized to .COPYSIGN(a, -1.0e+0) */
+float f(float a)
+{
+ return (float)__builtin_copysign(a, -3.0);
+}
+
+/* This gets converted to (float) abs((double) a)
+ With the patch it is optimized to abs(a) */
+float f2(float a)
+{
+ return (float)__builtin_copysign(a, 5.0);
+}
+
+/* { dg-final { scan-tree-dump-not "= __builtin_copysign" "optimized" } } */
+/* { dg-final { scan-tree-dump-not " double " "optimized" { target
ifn_copysign } } } */
+/* { dg-final { scan-tree-dump-times ".COPYSIGN" 1 "optimized" { target
ifn_copysign } } } */
+/* { dg-final { scan-tree-dump-times "-1.0e\\+0" 1 "optimized" { target
ifn_copysign } } } */
+/* { dg-final { scan-tree-dump-times " ABS_EXPR " 1 "optimized" { target
ifn_copysign } } } */
--
2.17.1
