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| author | Richard Biener <rguenther@suse.de> | 2022-12-02 14:52:20 +0100 |
|---|---|---|
| committer | Richard Biener <rguenther@suse.de> | 2022-12-05 10:22:53 +0100 |
| commit | 44c8402d35160515b3c09fd2bc239587e0c32a2b (patch) | |
| tree | f592f253098750358187f2ee53bce15c1b97b175 /gcc/tree-ssa.h | |
| parent | 824542bec24c09319fa55922a0162209a5f64963 (diff) | |
| download | gcc-44c8402d35160515b3c09fd2bc239587e0c32a2b.zip gcc-44c8402d35160515b3c09fd2bc239587e0c32a2b.tar.gz gcc-44c8402d35160515b3c09fd2bc239587e0c32a2b.tar.bz2 | |
tree-optimization/107833 - invariant motion of uninit uses
The following fixes a wrong-code bug caused by loop invariant motion
hoisting an expression using an uninitialized value outside of its
controlling condition causing IVOPTs to use that to rewrite a defined
value. PR107839 is a similar case involving a bogus uninit diagnostic.
PR tree-optimization/107833
PR tree-optimization/107839
* cfghooks.cc: Include tree.h.
* tree-ssa-loop-im.cc (movement_possibility): Wrap and
make stmts using any ssa_name_maybe_undef_p operand
to preserve execution.
(loop_invariant_motion_in_fun): Call mark_ssa_maybe_undefs
to init maybe-undefined status.
* tree-ssa-loop-ivopts.cc (ssa_name_maybe_undef_p,
ssa_name_set_maybe_undef, ssa_name_any_use_dominates_bb_p,
mark_ssa_maybe_undefs): Move ...
* tree-ssa.cc: ... here.
* tree-ssa.h (ssa_name_any_use_dominates_bb_p,
mark_ssa_maybe_undefs): Declare.
(ssa_name_maybe_undef_p, ssa_name_set_maybe_undef): Define.
* gcc.dg/torture/pr107833.c: New testcase.
* gcc.dg/uninit-pr107839.c: Likewise.
Diffstat (limited to 'gcc/tree-ssa.h')
| -rw-r--r-- | gcc/tree-ssa.h | 25 |
1 files changed, 25 insertions, 0 deletions
diff --git a/gcc/tree-ssa.h b/gcc/tree-ssa.h index 0085354..19c1eed 100644 --- a/gcc/tree-ssa.h +++ b/gcc/tree-ssa.h @@ -55,6 +55,31 @@ extern tree find_released_ssa_name (tree *, int *, void *); extern bool ssa_defined_default_def_p (tree t); extern bool ssa_undefined_value_p (tree, bool = true); extern bool gimple_uses_undefined_value_p (gimple *); + + +bool ssa_name_any_use_dominates_bb_p (tree var, basic_block bb); +extern void mark_ssa_maybe_undefs (void); + +/* Return TRUE iff VAR is marked as maybe-undefined. See + mark_ssa_maybe_undefs. */ + +static inline bool +ssa_name_maybe_undef_p (tree var) +{ + gcc_checking_assert (TREE_CODE (var) == SSA_NAME); + return TREE_VISITED (var); +} + +/* Set (or clear, depending on VALUE) VAR's maybe-undefined mark. */ + +static inline void +ssa_name_set_maybe_undef (tree var, bool value = true) +{ + gcc_checking_assert (TREE_CODE (var) == SSA_NAME); + TREE_VISITED (var) = value; +} + + extern void execute_update_addresses_taken (void); /* Given an edge_var_map V, return the PHI arg definition. */ |