diff options
Diffstat (limited to 'gcc/fold-const.c')
| -rw-r--r-- | gcc/fold-const.c | 31 |
1 files changed, 31 insertions, 0 deletions
diff --git a/gcc/fold-const.c b/gcc/fold-const.c index 220d1af..517d550 100644 --- a/gcc/fold-const.c +++ b/gcc/fold-const.c @@ -9267,6 +9267,37 @@ tree_expr_nonnegative_p (tree t) case RTL_EXPR: return rtl_expr_nonnegative_p (RTL_EXPR_RTL (t)); + case TARGET_EXPR: + { + tree temp = TARGET_EXPR_SLOT (t); + t = TARGET_EXPR_INITIAL (t); + + /* If the initializer is non-void, then it's a normal expression + that will be assigned to the slot. */ + if (!VOID_TYPE_P (t)) + return tree_expr_nonnegative_p (t); + + /* Otherwise, the initializer sets the slot in some way. One common + way is an assignment statement at the end of the initializer. */ + while (1) + { + if (TREE_CODE (t) == BIND_EXPR) + t = expr_last (BIND_EXPR_BODY (t)); + else if (TREE_CODE (t) == TRY_FINALLY_EXPR + || TREE_CODE (t) == TRY_CATCH_EXPR) + t = expr_last (TREE_OPERAND (t, 0)); + else if (TREE_CODE (t) == STATEMENT_LIST) + t = expr_last (t); + else + break; + } + if (TREE_CODE (t) == MODIFY_EXPR + && TREE_OPERAND (t, 0) == temp) + return tree_expr_nonnegative_p (TREE_OPERAND (t, 1)); + + return 0; + } + case CALL_EXPR: { tree fndecl = get_callee_fndecl (t); |