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| author | Andrew Pinski <quic_apinski@quicinc.com> | 2024-05-06 23:53:41 -0700 |
|---|---|---|
| committer | Andrew Pinski <quic_apinski@quicinc.com> | 2024-05-08 08:36:59 -0700 |
| commit | 5726de79e2154a16d8a045567d2cfad035f7ed19 (patch) | |
| tree | 57e8b06a5307fd2b9c706730fe4e34ecbc930f02 /gcc/match.pd | |
| parent | f4b86ab09dfe258c4780fcc7567ca8a275c96e7a (diff) | |
| download | gcc-5726de79e2154a16d8a045567d2cfad035f7ed19.zip gcc-5726de79e2154a16d8a045567d2cfad035f7ed19.tar.gz gcc-5726de79e2154a16d8a045567d2cfad035f7ed19.tar.bz2 | |
match: `a CMP nonnegative ? a : ABS<a>` simplified to just `ABS<a>` [PR112392]
We can optimize `a == nonnegative ? a : ABS<a>`, `a > nonnegative ? a : ABS<a>`
and `a >= nonnegative ? a : ABS<a>` into `ABS<a>`. This allows removal of
some extra comparison and extra conditional moves in some cases.
I don't remember where I had found though but it is simple to add so
let's add it.
Bootstrapped and tested on x86_64-linux-gnu with no regressions.
Note I have a secondary pattern for the equal case as either a or nonnegative
could be used.
PR tree-optimization/112392
gcc/ChangeLog:
* match.pd (`x CMP nonnegative ? x : ABS<x>`): New pattern;
where CMP is ==, > and >=.
(`x CMP nonnegative@y ? y : ABS<x>`): New pattern.
gcc/testsuite/ChangeLog:
* gcc.dg/tree-ssa/phi-opt-41.c: New test.
Signed-off-by: Andrew Pinski <quic_apinski@quicinc.com>
Diffstat (limited to 'gcc/match.pd')
| -rw-r--r-- | gcc/match.pd | 15 |
1 files changed, 15 insertions, 0 deletions
diff --git a/gcc/match.pd b/gcc/match.pd index 03a03c3..07e743a 100644 --- a/gcc/match.pd +++ b/gcc/match.pd @@ -5876,6 +5876,21 @@ DEFINE_INT_AND_FLOAT_ROUND_FN (RINT) (convert (absu:utype @0))) @3)))) +/* X > Positive ? X : ABS(X) -> ABS(X) */ +/* X >= Positive ? X : ABS(X) -> ABS(X) */ +/* X == Positive ? X : ABS(X) -> ABS(X) */ +(for cmp (eq gt ge) + (simplify + (cond (cmp:c @0 tree_expr_nonnegative_p@1) @0 (abs@3 @0)) + (if (INTEGRAL_TYPE_P (type)) + @3))) + +/* X == Positive ? Positive : ABS(X) -> ABS(X) */ +(simplify + (cond (eq:c @0 tree_expr_nonnegative_p@1) @1 (abs@3 @0)) + (if (INTEGRAL_TYPE_P (type)) + @3)) + /* (X + 1) > Y ? -X : 1 simplifies to X >= Y ? -X : 1 when X is unsigned, as when X + 1 overflows, X is -1, so -X == 1. */ (simplify |