diff options
| author | rguenth <rguenth@138bc75d-0d04-0410-961f-82ee72b054a4> | 2007-12-05 21:45:15 +0000 |
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| committer | rguenth <rguenth@138bc75d-0d04-0410-961f-82ee72b054a4> | 2007-12-05 21:45:15 +0000 |
| commit | d9d723d91ff90f13e0162307658b2cb9e92d6dff (patch) | |
| tree | 560a457c88a46b8a12942c609706fa03abae2aa0 /gcc/tree-ssa-forwprop.c | |
| parent | 68685205020781b84a8bccca470b36443e963c08 (diff) | |
| download | gcc-d9d723d91ff90f13e0162307658b2cb9e92d6dff.tar.gz | |
2007-12-05 Richard Guenther <rguenther@suse.de>
PR tree-optimization/34138
* tree-ssa-forwprop.c (tree_ssa_forward_propagate_single_use_vars):
Do not forward propagate addresses if that changes volatileness of
the pointed-to type.
* gcc.c-torture/compile/pr34138.c: New testcase.
git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@130632 138bc75d-0d04-0410-961f-82ee72b054a4
Diffstat (limited to 'gcc/tree-ssa-forwprop.c')
| -rw-r--r-- | gcc/tree-ssa-forwprop.c | 5 |
1 files changed, 4 insertions, 1 deletions
diff --git a/gcc/tree-ssa-forwprop.c b/gcc/tree-ssa-forwprop.c index f368c3321c4..2da17c8827d 100644 --- a/gcc/tree-ssa-forwprop.c +++ b/gcc/tree-ssa-forwprop.c @@ -956,12 +956,15 @@ tree_ssa_forward_propagate_single_use_vars (void) } if (TREE_CODE (rhs) == ADDR_EXPR - /* We can also disregard changes in CV qualifiers for + /* We can also disregard changes in const qualifiers for the dereferenced value. */ || ((TREE_CODE (rhs) == NOP_EXPR || TREE_CODE (rhs) == CONVERT_EXPR) && TREE_CODE (TREE_OPERAND (rhs, 0)) == ADDR_EXPR && POINTER_TYPE_P (TREE_TYPE (rhs)) + /* But do not propagate changes in volatileness. */ + && (TYPE_VOLATILE (TREE_TYPE (TREE_TYPE (rhs))) + == TYPE_VOLATILE (TREE_TYPE (TREE_TYPE (TREE_OPERAND (rhs, 0))))) && types_compatible_p (TREE_TYPE (TREE_TYPE (TREE_OPERAND (rhs, 0))), TREE_TYPE (TREE_TYPE (rhs))))) { |