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 <quic_eikag...@quicinc.com> --- gcc/match.pd | 20 +++++++++++++++++--- gcc/testsuite/gcc.dg/tree-ssa/pr112472.c | 22 ++++++++++++++++++++++ 2 files changed, 39 insertions(+), 3 deletions(-) create mode 100644 gcc/testsuite/gcc.dg/tree-ssa/pr112472.c diff --git a/gcc/match.pd b/gcc/match.pd index 940292d0d49..a1668c4c9dc 100644 --- a/gcc/match.pd +++ b/gcc/match.pd @@ -8527,15 +8527,29 @@ DEFINE_INT_AND_FLOAT_ROUND_FN (RINT) 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 (types_match (type, TREE_TYPE (@1))) + (IFN_COPYSIGN @0 @1) + /* (trunc)copysign (extend)x, CST) to copysign (x, -1.0/1.0) */ + (if (REAL_VALUE_NEGATIVE (TREE_REAL_CST (@1))) + (IFN_COPYSIGN @0 { build_minus_one_cst (type); }) + (IFN_COPYSIGN @0 { build_one_cst (type); })))))) + +/* (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