diff options
Diffstat (limited to 'gcc/tree.c')
| -rw-r--r-- | gcc/tree.c | 11 |
1 files changed, 9 insertions, 2 deletions
@@ -1742,10 +1742,12 @@ save_expr (expr) /* If the tree evaluates to a constant, then we don't want to hide that fact (i.e. this allows further folding, and direct checks for constants). + However, a read-only object that has side effects cannot be bypassed. Since it is no problem to reevaluate literals, we just return the literal node. */ - if (TREE_CONSTANT (t) || TREE_READONLY (t) || TREE_CODE (t) == SAVE_EXPR) + if (TREE_CONSTANT (t) || (TREE_READONLY (t) && ! TREE_SIDE_EFFECTS (t)) + || TREE_CODE (t) == SAVE_EXPR) return t; t = build (SAVE_EXPR, TREE_TYPE (expr), t, current_function_decl, NULL); @@ -1852,7 +1854,12 @@ stabilize_reference_1 (e) register int length; register enum tree_code code = TREE_CODE (e); - if (TREE_CONSTANT (e) || TREE_READONLY (e) || code == SAVE_EXPR) + /* We cannot ignore const expressions because it might be a reference + to a const array but whose index contains side-effects. But we can + ignore things that are actual constant or that already have been + handled by this function. */ + + if (TREE_CONSTANT (e) || code == SAVE_EXPR) return e; switch (TREE_CODE_CLASS (code)) |