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| author | Martin Jambor <mjambor@suse.cz> | 2008-12-02 15:30:55 +0100 |
|---|---|---|
| committer | Martin Jambor <jamborm@gcc.gnu.org> | 2008-12-02 15:30:55 +0100 |
| commit | d47a01516c91f35d0f60d2e636d6e3724ee400b3 (patch) | |
| tree | 773f6a892e8147c25699be344fdb943a6a5c0ae3 /gcc/tree-ssa-forwprop.c | |
| parent | 96e4a79fbd9ee3c390c77bc2bff69a783ee13ff2 (diff) | |
| download | gcc-d47a01516c91f35d0f60d2e636d6e3724ee400b3.tar.gz | |
re PR middle-end/37861 (Bogus array bounds warning)
2008-12-02 Martin Jambor <mjambor@suse.cz>
PR middle-end/37861
* tree-ssa-forwprop.c (forward_propagate_addr_expr_1): Do not check
for INDIRECT_REFs.
(forward_propagate_addr_into_variable_array_index): Check that the
offset is not computed from a MULT_EXPR, use is_gimple_assign rather
than the gimple code directly.
From-SVN: r142355
Diffstat (limited to 'gcc/tree-ssa-forwprop.c')
| -rw-r--r-- | gcc/tree-ssa-forwprop.c | 27 |
1 files changed, 16 insertions, 11 deletions
diff --git a/gcc/tree-ssa-forwprop.c b/gcc/tree-ssa-forwprop.c index b19879f7909..bfd7146d490 100644 --- a/gcc/tree-ssa-forwprop.c +++ b/gcc/tree-ssa-forwprop.c @@ -613,19 +613,27 @@ forward_propagate_addr_into_variable_array_index (tree offset, tree index; gimple offset_def, use_stmt = gsi_stmt (*use_stmt_gsi); - /* Try to find an expression for a proper index. This is either - a multiplication expression by the element size or just the - ssa name we came along in case the element size is one. */ + /* Get the offset's defining statement. */ + offset_def = SSA_NAME_DEF_STMT (offset); + + /* Try to find an expression for a proper index. This is either a + multiplication expression by the element size or just the ssa name we came + along in case the element size is one. In that case, however, we do not + allow multiplications because they can be computing index to a higher + level dimension (PR 37861). */ if (integer_onep (TYPE_SIZE_UNIT (TREE_TYPE (TREE_TYPE (def_rhs))))) - index = offset; - else { - /* Get the offset's defining statement. */ - offset_def = SSA_NAME_DEF_STMT (offset); + if (is_gimple_assign (offset_def) + && gimple_assign_rhs_code (offset_def) == MULT_EXPR) + return false; + index = offset; + } + else + { /* The statement which defines OFFSET before type conversion must be a simple GIMPLE_ASSIGN. */ - if (gimple_code (offset_def) != GIMPLE_ASSIGN) + if (!is_gimple_assign (offset_def)) return false; /* The RHS of the statement which defines OFFSET must be a @@ -805,9 +813,6 @@ forward_propagate_addr_expr_1 (tree name, tree def_rhs, array_ref = TREE_OPERAND (def_rhs, 0); if (TREE_CODE (array_ref) != ARRAY_REF || TREE_CODE (TREE_TYPE (TREE_OPERAND (array_ref, 0))) != ARRAY_TYPE - /* Avoid accessing hidden multidimensional arrays in this way or VRP - might give out bogus warnings (see PR 37861) */ - || TREE_CODE (TREE_OPERAND (array_ref, 0)) == INDIRECT_REF || !integer_zerop (TREE_OPERAND (array_ref, 1))) return false; |