diff options
Diffstat (limited to 'gcc/builtins.c')
| -rw-r--r-- | gcc/builtins.c | 60 |
1 files changed, 49 insertions, 11 deletions
diff --git a/gcc/builtins.c b/gcc/builtins.c index 8621e0db511..e3c91dc635b 100644 --- a/gcc/builtins.c +++ b/gcc/builtins.c @@ -479,13 +479,16 @@ c_strlen (tree src, int only_value) else offset = tree_low_cst (offset_node, 0); - /* If the offset is known to be out of bounds, the front-end should - have warned already. We call strlen at runtime. - - ??? Perhaps we should turn this into an assert and force - front-ends to define offsets whtin boundaries. */ + /* If the offset is known to be out of bounds, warn, and call strlen at + runtime. */ if (offset < 0 || offset > max) { + /* Suppress multiple warnings for propagated constant strings. */ + if (! TREE_NO_WARNING (src)) + { + warning (0, "offset outside bounds of constant string"); + TREE_NO_WARNING (src) = 1; + } return NULL_TREE; } @@ -8734,7 +8737,7 @@ var_decl_component_p (tree var) static tree fold_builtin_memset (tree dest, tree c, tree len, tree type, bool ignore) { - tree var, ret; + tree var, ret, etype; unsigned HOST_WIDE_INT length, cval; if (! validate_arg (dest, POINTER_TYPE) @@ -8761,15 +8764,19 @@ fold_builtin_memset (tree dest, tree c, tree len, tree type, bool ignore) if (TREE_THIS_VOLATILE (var)) return NULL_TREE; - if (!INTEGRAL_TYPE_P (TREE_TYPE (var)) - && !POINTER_TYPE_P (TREE_TYPE (var))) + etype = TREE_TYPE (var); + if (TREE_CODE (etype) == ARRAY_TYPE) + etype = TREE_TYPE (etype); + + if (!INTEGRAL_TYPE_P (etype) + && !POINTER_TYPE_P (etype)) return NULL_TREE; if (! var_decl_component_p (var)) return NULL_TREE; length = tree_low_cst (len, 1); - if (GET_MODE_SIZE (TYPE_MODE (TREE_TYPE (var))) != length + if (GET_MODE_SIZE (TYPE_MODE (etype)) != length || get_pointer_alignment (dest, BIGGEST_ALIGNMENT) / BITS_PER_UNIT < (int) length) return NULL_TREE; @@ -8791,8 +8798,10 @@ fold_builtin_memset (tree dest, tree c, tree len, tree type, bool ignore) cval |= (cval << 31) << 1; } - ret = build_int_cst_type (TREE_TYPE (var), cval); - ret = build2 (MODIFY_EXPR, TREE_TYPE (var), var, ret); + ret = build_int_cst_type (etype, cval); + var = build_fold_indirect_ref (fold_convert (build_pointer_type (etype), + dest)); + ret = build2 (MODIFY_EXPR, etype, var, ret); if (ignore) return ret; @@ -8944,8 +8953,37 @@ fold_builtin_memory_op (tree dest, tree src, tree len, tree type, bool ignore, i Perhaps we ought to inherit type from non-VOID argument here? */ STRIP_NOPS (src); STRIP_NOPS (dest); + /* As we fold (void *)(p + CST) to (void *)p + CST undo this here. */ + if (TREE_CODE (src) == POINTER_PLUS_EXPR) + { + tree tem = TREE_OPERAND (src, 0); + STRIP_NOPS (tem); + if (tem != TREE_OPERAND (src, 0)) + src = build1 (NOP_EXPR, TREE_TYPE (tem), src); + } + if (TREE_CODE (dest) == POINTER_PLUS_EXPR) + { + tree tem = TREE_OPERAND (dest, 0); + STRIP_NOPS (tem); + if (tem != TREE_OPERAND (dest, 0)) + dest = build1 (NOP_EXPR, TREE_TYPE (tem), dest); + } srctype = TREE_TYPE (TREE_TYPE (src)); + if (srctype + && TREE_CODE (srctype) == ARRAY_TYPE) + { + srctype = TREE_TYPE (srctype); + STRIP_NOPS (src); + src = build1 (NOP_EXPR, build_pointer_type (srctype), src); + } desttype = TREE_TYPE (TREE_TYPE (dest)); + if (desttype + && TREE_CODE (desttype) == ARRAY_TYPE) + { + desttype = TREE_TYPE (desttype); + STRIP_NOPS (dest); + dest = build1 (NOP_EXPR, build_pointer_type (desttype), dest); + } if (!srctype || !desttype || !TYPE_SIZE_UNIT (srctype) || !TYPE_SIZE_UNIT (desttype) |