newivs_index, params_index);
tree ub = clast_to_gcc_expression (type, stmt->UB, region, newivs,
newivs_index, params_index);
- tree one = POINTER_TYPE_P (type) ? size_one_node
- : fold_convert (type, integer_one_node);
- /* Adding +1 and using LT_EXPR helps with loop latches that have a
- loop iteration count of "PARAMETER - 1". For PARAMETER == 0 this becomes
- 2^{32|64}, and the condition lb <= ub is true, even if we do not want this.
- However lb < ub + 1 is false, as expected. */
- tree ub_one = fold_build2 (POINTER_TYPE_P (type) ? POINTER_PLUS_EXPR
- : PLUS_EXPR, type, ub, one);
-
- /* When ub + 1 wraps around, use lb <= ub. */
- if (integer_zerop (ub_one))
+ /* When ub is simply a constant or a parameter, use lb <= ub. */
+ if (TREE_CODE (ub) == INTEGER_CST || TREE_CODE (ub) == SSA_NAME)
cond_expr = fold_build2 (LE_EXPR, boolean_type_node, lb, ub);
else
- cond_expr = fold_build2 (LT_EXPR, boolean_type_node, lb, ub_one);
+ {
+ tree one = (POINTER_TYPE_P (type)
+ ? size_one_node
+ : fold_convert (type, integer_one_node));
+ /* Adding +1 and using LT_EXPR helps with loop latches that have a
+ loop iteration count of "PARAMETER - 1". For PARAMETER == 0 this becomes
+ 2^k-1 due to integer overflow, and the condition lb <= ub is true,
+ even if we do not want this. However lb < ub + 1 is false, as
+ expected. */
+ tree ub_one = fold_build2 (POINTER_TYPE_P (type) ? POINTER_PLUS_EXPR
+ : PLUS_EXPR, type, ub, one);
+
+ cond_expr = fold_build2 (LT_EXPR, boolean_type_node, lb, ub_one);
+ }
exit_edge = create_empty_if_region_on_edge (entry_edge, cond_expr);