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| author | Richard Biener <rguenther@suse.de> | 2022-07-26 11:52:49 +0200 |
|---|---|---|
| committer | Richard Biener <rguenther@suse.de> | 2022-11-11 15:04:53 +0100 |
| commit | 4b3874d803e7961f38b22fa798517a63171bb985 (patch) | |
| tree | 6ff6be0480daf66bd4865141212a859ded2b1e93 /gcc | |
| parent | e0cfde7e8b36a8176b661af16dff91ebf4f99a8e (diff) | |
| download | gcc-4b3874d803e7961f38b22fa798517a63171bb985.zip gcc-4b3874d803e7961f38b22fa798517a63171bb985.tar.gz gcc-4b3874d803e7961f38b22fa798517a63171bb985.tar.bz2 | |
tree-optimization/105142 - improve maybe_fold_comparisons_from_match_pd fix
The following improves on the fix for PR105142 which restricted the
expression lookup used for maybe_fold_comparisons_from_match_pd to
avoid picking up flow-sensitive info for use in places where guarding
conditions do not hold. Instead of not allowing to expand SSA
definitions there the following temporarily clears flow-sensitive
info on the SSA names and restores it when finished matching.
PR tree-optimization/105142
* gimple-fold.cc (fosa_unwind): New global.
(follow_outer_ssa_edges): When the SSA definition to follow
is does not dominate fosa_bb, temporarily clear flow-sensitive
info. Make sure to not expand stmts with not defined overflow.
(maybe_fold_comparisons_from_match_pd): Set up unwind stack
for follow_outer_ssa_edges and unwind flow-sensitive info
clearing after matching.
Diffstat (limited to 'gcc')
| -rw-r--r-- | gcc/gimple-fold.cc | 25 |
1 files changed, 24 insertions, 1 deletions
diff --git a/gcc/gimple-fold.cc b/gcc/gimple-fold.cc index 8d40798..0a212e6 100644 --- a/gcc/gimple-fold.cc +++ b/gcc/gimple-fold.cc @@ -6916,6 +6916,7 @@ and_comparisons_1 (tree type, enum tree_code code1, tree op1a, tree op1b, } static basic_block fosa_bb; +static vec<std::pair<tree, void *> > *fosa_unwind; static tree follow_outer_ssa_edges (tree val) { @@ -6929,7 +6930,21 @@ follow_outer_ssa_edges (tree val) && (def_bb == fosa_bb || dominated_by_p (CDI_DOMINATORS, fosa_bb, def_bb)))) return val; - return NULL_TREE; + /* We cannot temporarily rewrite stmts with undefined overflow + behavior, so avoid expanding them. */ + if ((ANY_INTEGRAL_TYPE_P (TREE_TYPE (val)) + || POINTER_TYPE_P (TREE_TYPE (val))) + && !TYPE_OVERFLOW_WRAPS (TREE_TYPE (val))) + return NULL_TREE; + /* If the definition does not dominate fosa_bb temporarily reset + flow-sensitive info. */ + if (val->ssa_name.info.range_info) + { + fosa_unwind->safe_push (std::make_pair + (val, val->ssa_name.info.range_info)); + val->ssa_name.info.range_info = NULL; + } + return val; } return val; } @@ -6988,9 +7003,14 @@ maybe_fold_comparisons_from_match_pd (tree type, enum tree_code code, type, gimple_assign_lhs (stmt1), gimple_assign_lhs (stmt2)); fosa_bb = outer_cond_bb; + auto_vec<std::pair<tree, void *>, 8> unwind_stack; + fosa_unwind = &unwind_stack; if (op.resimplify (NULL, (!outer_cond_bb ? follow_all_ssa_edges : follow_outer_ssa_edges))) { + fosa_unwind = NULL; + for (auto p : unwind_stack) + p.first->ssa_name.info.range_info = p.second; if (gimple_simplified_result_is_gimple_val (&op)) { tree res = op.ops[0]; @@ -7012,6 +7032,9 @@ maybe_fold_comparisons_from_match_pd (tree type, enum tree_code code, return build2 ((enum tree_code)op.code, op.type, op0, op1); } } + fosa_unwind = NULL; + for (auto p : unwind_stack) + p.first->ssa_name.info.range_info = p.second; return NULL_TREE; } |