diff options
Diffstat (limited to 'gcc/tree-ssa-ifcombine.c')
| -rw-r--r-- | gcc/tree-ssa-ifcombine.c | 13 |
1 files changed, 9 insertions, 4 deletions
diff --git a/gcc/tree-ssa-ifcombine.c b/gcc/tree-ssa-ifcombine.c index 89fd61d..9403857 100644 --- a/gcc/tree-ssa-ifcombine.c +++ b/gcc/tree-ssa-ifcombine.c @@ -167,17 +167,22 @@ recognize_single_bit_test (tree cond_expr, tree *name, tree *bit) && integer_onep (TREE_OPERAND (t, 1)) && TREE_CODE (TREE_OPERAND (t, 0)) == SSA_NAME) { - t = TREE_OPERAND (t, 0); + tree orig_name = TREE_OPERAND (t, 0); + + /* Look through copies and conversions to eventually + find the stmt that computes the shift. */ + t = orig_name; do { t = SSA_NAME_DEF_STMT (t); if (TREE_CODE (t) != GIMPLE_MODIFY_STMT) - return false; + break; t = GIMPLE_STMT_OPERAND (t, 1); if (TREE_CODE (t) == NOP_EXPR || TREE_CODE (t) == CONVERT_EXPR) t = TREE_OPERAND (t, 0); } while (TREE_CODE (t) == SSA_NAME); + /* If we found such, decompose it. */ if (TREE_CODE (t) == RSHIFT_EXPR) { /* op0 & (1 << op1) */ @@ -187,8 +192,8 @@ recognize_single_bit_test (tree cond_expr, tree *name, tree *bit) else { /* t & 1 */ - *bit = integer_one_node; - *name = t; + *bit = integer_zero_node; + *name = orig_name; } return true; |