diff options
| author | Richard Biener <rguenther@suse.de> | 2023-07-04 12:52:27 +0200 |
|---|---|---|
| committer | Richard Biener <rguenther@suse.de> | 2023-07-04 14:13:33 +0200 |
| commit | 819285ef10a87d663f8c181c06aa88d1d9f75aed (patch) | |
| tree | 362a9bf09cf73b7063c2136ad1d58cd8b3725f56 /gcc/tree-ssa-phiopt.cc | |
| parent | 86ff0533fcb442be17942eef16f8b8db466c4fd4 (diff) | |
| download | gcc-819285ef10a87d663f8c181c06aa88d1d9f75aed.zip gcc-819285ef10a87d663f8c181c06aa88d1d9f75aed.tar.gz gcc-819285ef10a87d663f8c181c06aa88d1d9f75aed.tar.bz2 | |
tree-optimization/110491 - PHI-OPT and undefs
The following makes sure to not make conditional undefs in PHI arguments
unconditional by folding cond ? arg1 : arg2.
PR tree-optimization/110491
* tree-ssa-phiopt.cc (match_simplify_replacement): Check
whether the PHI args are possibly undefined before folding
the COND_EXPR.
* gcc.dg/torture/pr110491.c: New testcase.
Diffstat (limited to 'gcc/tree-ssa-phiopt.cc')
| -rw-r--r-- | gcc/tree-ssa-phiopt.cc | 7 |
1 files changed, 7 insertions, 0 deletions
diff --git a/gcc/tree-ssa-phiopt.cc b/gcc/tree-ssa-phiopt.cc index 31a7c39..467c9fd 100644 --- a/gcc/tree-ssa-phiopt.cc +++ b/gcc/tree-ssa-phiopt.cc @@ -785,6 +785,13 @@ match_simplify_replacement (basic_block cond_bb, basic_block middle_bb, arg_false = arg0; } + /* Do not make conditional undefs unconditional. */ + if ((TREE_CODE (arg_true) == SSA_NAME + && ssa_name_maybe_undef_p (arg_true)) + || (TREE_CODE (arg_false) == SSA_NAME + && ssa_name_maybe_undef_p (arg_false))) + return false; + tree type = TREE_TYPE (gimple_phi_result (phi)); result = gimple_simplify_phiopt (early_p, type, stmt, arg_true, arg_false, |