| Message ID | 20240924085736.29467-1-quic_eikagupt@quicinc.com |
|---|---|
| State | New |
| Headers | show |
| Series | MATCH: Simplify `(trunc)copysign ((extend)x, CST)` to `copysign (x, -1.0/1.0)` [PR112472] | expand |
On 9/24/24 2:57 AM, Eikansh Gupta wrote: > 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. One might argue that -0.0/+0.0 are even better than -1.0/1.0 as the 0.0 variants are cheaper to construct. You'd have to check that we honor signed zeros.... jeff
On Tue, Sep 24, 2024 at 10:58 AM Eikansh Gupta <quic_eikagupt@quicinc.com> wrote: > > 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)`. Please always split unrelated transforms. The abs transform is OK. We already have /* Simplify (trunc)copysign ((extend)x, (extend)y) to copysignf (x, y), x,y is float value, similar for _Float16/double. */ (for copysigns (COPYSIGN_ALL) (simplify (convert (copysigns (convert@2 @0) (convert @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)))) you could have extended that to cover the REAL_CST case via matching (convert (copysigns (convert@2 @0) (convert2? @1))) I think. Can you try? > 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. > --- > gcc/match.pd | 24 +++++++++++++++++++++++- > gcc/testsuite/gcc.dg/tree-ssa/pr112472.c | 22 ++++++++++++++++++++++ > 2 files changed, 45 insertions(+), 1 deletion(-) > create mode 100644 gcc/testsuite/gcc.dg/tree-ssa/pr112472.c > > diff --git a/gcc/match.pd b/gcc/match.pd > index 940292d0d49..52dc8b539fc 100644 > --- a/gcc/match.pd > +++ b/gcc/match.pd > @@ -8535,7 +8535,29 @@ DEFINE_INT_AND_FLOAT_ROUND_FN (RINT) > && TYPE_PRECISION (type) < TYPE_PRECISION (TREE_TYPE (@2)) > && direct_internal_fn_supported_p (IFN_COPYSIGN, > type, OPTIMIZE_FOR_BOTH)) > - (IFN_COPYSIGN @0 @1)))) > + (IFN_COPYSIGN @0 @1))) > + /* (trunc)copysign (extend)x, CST) to copysign (x, -1.0/1.0) */ > + (simplify > + (convert (copysigns (convert@2 @0) REAL_CST@1)) > + (if (optimize > + && !HONOR_SNANS (@2) > + && types_match (type, TREE_TYPE (@0)) > + && TYPE_PRECISION (type) < TYPE_PRECISION (TREE_TYPE (@2)) > + && direct_internal_fn_supported_p (IFN_COPYSIGN, > + type, OPTIMIZE_FOR_BOTH)) > + (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 >
diff --git a/gcc/match.pd b/gcc/match.pd index 940292d0d49..52dc8b539fc 100644 --- a/gcc/match.pd +++ b/gcc/match.pd @@ -8535,7 +8535,29 @@ DEFINE_INT_AND_FLOAT_ROUND_FN (RINT) && TYPE_PRECISION (type) < TYPE_PRECISION (TREE_TYPE (@2)) && direct_internal_fn_supported_p (IFN_COPYSIGN, type, OPTIMIZE_FOR_BOTH)) - (IFN_COPYSIGN @0 @1)))) + (IFN_COPYSIGN @0 @1))) + /* (trunc)copysign (extend)x, CST) to copysign (x, -1.0/1.0) */ + (simplify + (convert (copysigns (convert@2 @0) REAL_CST@1)) + (if (optimize + && !HONOR_SNANS (@2) + && types_match (type, TREE_TYPE (@0)) + && TYPE_PRECISION (type) < TYPE_PRECISION (TREE_TYPE (@2)) + && direct_internal_fn_supported_p (IFN_COPYSIGN, + type, OPTIMIZE_FOR_BOTH)) + (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 } } } */