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| author | Richard Biener <rguenther@suse.de> | 2022-07-05 11:38:52 +0200 |
|---|---|---|
| committer | Richard Biener <rguenther@suse.de> | 2022-07-05 14:11:51 +0200 |
| commit | c3d2600cfb476e576fd27f3f29f49e968e86774d (patch) | |
| tree | 628cabfcc381f5391a4feca01a243160c50a0897 | |
| parent | 1a6e0d8252a71c61d4dc616044fb25b5ac2cfffb (diff) | |
| download | gcc-c3d2600cfb476e576fd27f3f29f49e968e86774d.zip gcc-c3d2600cfb476e576fd27f3f29f49e968e86774d.tar.gz gcc-c3d2600cfb476e576fd27f3f29f49e968e86774d.tar.bz2 | |
tree-optimization/106186 - propagate out virtual LC PHI nodes properly
The code to remove LC PHI nodes in clean_up_loop_closed_phi does not handle
virtual operands because may_propagate_copy generally returns false
for them. The following copies the merge_blocks variant for
dealing with them.
This fixes a missed jump threading in gcc.dg/auto-init-uninit-4.c
which manifests in bogus uninit diagnostics.
PR tree-optimization/106186
* tree-ssa-propagate.cc (clean_up_loop_closed_phi):
Properly handle virtual PHI nodes.
| -rw-r--r-- | gcc/tree-ssa-propagate.cc | 16 |
1 files changed, 15 insertions, 1 deletions
diff --git a/gcc/tree-ssa-propagate.cc b/gcc/tree-ssa-propagate.cc index 163b24f..9dc4bfd 100644 --- a/gcc/tree-ssa-propagate.cc +++ b/gcc/tree-ssa-propagate.cc @@ -1272,7 +1272,21 @@ clean_up_loop_closed_phi (function *fun) rhs = gimple_phi_arg_def (phi, 0); lhs = gimple_phi_result (phi); - if (rhs && may_propagate_copy (lhs, rhs)) + if (virtual_operand_p (rhs)) + { + imm_use_iterator iter; + use_operand_p use_p; + gimple *stmt; + + FOR_EACH_IMM_USE_STMT (stmt, iter, lhs) + FOR_EACH_IMM_USE_ON_STMT (use_p, iter) + SET_USE (use_p, rhs); + + if (SSA_NAME_OCCURS_IN_ABNORMAL_PHI (lhs)) + SSA_NAME_OCCURS_IN_ABNORMAL_PHI (rhs) = 1; + remove_phi_node (&gsi, true); + } + else if (may_propagate_copy (lhs, rhs)) { /* Dump details. */ if (dump_file && (dump_flags & TDF_DETAILS)) |