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Diffstat (limited to 'gcc/tree-ssa-strlen.c')
| -rw-r--r-- | gcc/tree-ssa-strlen.c | 19 |
1 files changed, 16 insertions, 3 deletions
diff --git a/gcc/tree-ssa-strlen.c b/gcc/tree-ssa-strlen.c index a2d514c..8971c7d 100644 --- a/gcc/tree-ssa-strlen.c +++ b/gcc/tree-ssa-strlen.c @@ -3155,14 +3155,27 @@ strlen_check_and_optimize_stmt (gimple_stmt_iterator *gsi) { tree off = integer_zero_node; unsigned HOST_WIDE_INT coff = 0; - int idx = -1; + int idx = 0; tree rhs1 = gimple_assign_rhs1 (stmt); if (code == MEM_REF) { idx = get_stridx (TREE_OPERAND (rhs1, 0)); - off = TREE_OPERAND (rhs1, 1); + if (idx > 0) + { + strinfo *si = get_strinfo (idx); + if (si + && si->nonzero_chars + && TREE_CODE (si->nonzero_chars) == INTEGER_CST + && (wi::to_widest (si->nonzero_chars) + >= wi::to_widest (off))) + off = TREE_OPERAND (rhs1, 1); + else + /* This case is not useful. See if get_addr_stridx + returns something usable. */ + idx = 0; + } } - else + if (idx <= 0) idx = get_addr_stridx (rhs1, NULL_TREE, &coff); if (idx > 0) { |