In the testcase provided, we would match f_plus but not g_plus due to a missing `:c` on the plus operator. This fixes the oversight there.
Note this was noted in https://github.com/llvm/llvm-project/issues/76318 . Committed as obvious after bootstrap/test on x86_64-linux-gnu. PR tree-optimization/19832 gcc/ChangeLog: * match.pd (`(a != b) ? (a + b) : (2 * a)`): Add `:c` on the plus operator. gcc/testsuite/ChangeLog: * gcc.dg/tree-ssa/phi-opt-same-2.c: New test. Signed-off-by: Andrew Pinski <quic_apin...@quicinc.com> --- gcc/match.pd | 2 +- .../gcc.dg/tree-ssa/phi-opt-same-2.c | 19 +++++++++++++++++++ 2 files changed, 20 insertions(+), 1 deletion(-) create mode 100644 gcc/testsuite/gcc.dg/tree-ssa/phi-opt-same-2.c diff --git a/gcc/match.pd b/gcc/match.pd index d57e29bfe1d..a980c4d7e94 100644 --- a/gcc/match.pd +++ b/gcc/match.pd @@ -5694,7 +5694,7 @@ DEFINE_INT_AND_FLOAT_ROUND_FN (RINT) @2))) /* (a != b) ? (a + b) : (2 * a) -> (a + b) */ (simplify - (cnd (ne:c @0 @1) (plus@2 @0 @1) (mult @0 uniform_integer_cst_p@3)) + (cnd (ne:c @0 @1) (plus:c@2 @0 @1) (mult @0 uniform_integer_cst_p@3)) (if (wi::to_wide (uniform_integer_cst_p (@3)) == 2) @2)) ) diff --git a/gcc/testsuite/gcc.dg/tree-ssa/phi-opt-same-2.c b/gcc/testsuite/gcc.dg/tree-ssa/phi-opt-same-2.c new file mode 100644 index 00000000000..94fb6a92cea --- /dev/null +++ b/gcc/testsuite/gcc.dg/tree-ssa/phi-opt-same-2.c @@ -0,0 +1,19 @@ +/* { dg-do compile } */ +/* { dg-options "-O2 -fdump-tree-phiopt1 -fdump-tree-optimized" } */ +/* PR tree-optimization/19832 */ + +int f_plus(int a, int b) +{ + if (a != b) return a + b; + return a + a; +} + +int g_plus(int a, int b) +{ + if (b != a) return a + b; + return a + a; +} + +/* All of the above function's if should have been optimized away even in phiopt1. */ +/* { dg-final { scan-tree-dump-not "if " "phiopt1" } } */ +/* { dg-final { scan-tree-dump-not "if " "optimized" } } */ -- 2.39.3
