On 2 January 2018 at 19:29, Richard Biener <richard.guent...@gmail.com> wrote:
> On Thu, Dec 28, 2017 at 8:42 AM, Prathamesh Kulkarni
> <prathamesh.kulka...@linaro.org> wrote:
>> On 21 December 2017 at 12:53, Prathamesh Kulkarni
>> <prathamesh.kulka...@linaro.org> wrote:
>>> Hi Jakub,
>>> Based on your suggestions in PR83501, I have updated the patch to
>>> check for integer_zerop for 2nd operand of mem_ref.
>>>
>>> With the patch, Warray-bounds started warning for the following test
>>> in Warray-bounds-3.c in line 362 and thus I removed xfail on it:
>>> TM (a5, "0123", ma.a5 + i, ma.a5);
>>>
>>> Does it look OK ?
>>> Validation in progress.
>> ping https://gcc.gnu.org/ml/gcc-patches/2017-12/msg01415.html
>
> Ok.
Thanks, I removed the Warray-bounds-3.c hunk since that was added in
interim by Martin Sebor.
Committed the attached version in r256180 after verifying
bootstrap+test passes on x86_64-unknown-linux-gnu.
Thanks,
Prathamesh
>
> RIchard.
>
>> Thanks,
>> Prathamesh
>>>
>>> Thanks,
>>> Prathamesh
diff --git a/gcc/testsuite/gcc.dg/tree-ssa/pr83501.c
b/gcc/testsuite/gcc.dg/tree-ssa/pr83501.c
new file mode 100644
index 00000000000..d8d3bf6039a
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/tree-ssa/pr83501.c
@@ -0,0 +1,14 @@
+/* { dg-do compile } */
+/* { dg-options "-O2 -fdump-tree-strlen" } */
+
+char a[4];
+
+void f (void)
+{
+ __builtin_strcpy (a, "abc");
+
+ if (__builtin_strlen (a) != 3)
+ __builtin_abort ();
+}
+
+/* { dg-final { scan-tree-dump-not "__builtin_strlen" "strlen" } } */
diff --git a/gcc/tree-ssa-strlen.c b/gcc/tree-ssa-strlen.c
index 8971c7df4f3..f1d4f6ef059 100644
--- a/gcc/tree-ssa-strlen.c
+++ b/gcc/tree-ssa-strlen.c
@@ -2769,6 +2769,21 @@ handle_pointer_plus (gimple_stmt_iterator *gsi)
}
}
+/* Check if RHS is string_cst possibly wrapped by mem_ref. */
+static tree
+get_string_cst (tree rhs)
+{
+ if (TREE_CODE (rhs) == MEM_REF
+ && integer_zerop (TREE_OPERAND (rhs, 1)))
+ {
+ rhs = TREE_OPERAND (rhs, 0);
+ if (TREE_CODE (rhs) == ADDR_EXPR)
+ rhs = TREE_OPERAND (rhs, 0);
+ }
+
+ return (TREE_CODE (rhs) == STRING_CST) ? rhs : NULL_TREE;
+}
+
/* Handle a single character store. */
static bool
@@ -2924,11 +2939,11 @@ handle_char_store (gimple_stmt_iterator *gsi)
}
}
else if (idx == 0
- && TREE_CODE (gimple_assign_rhs1 (stmt)) == STRING_CST
+ && (rhs = get_string_cst (gimple_assign_rhs1 (stmt)))
&& ssaname == NULL_TREE
&& TREE_CODE (TREE_TYPE (lhs)) == ARRAY_TYPE)
{
- size_t l = strlen (TREE_STRING_POINTER (gimple_assign_rhs1 (stmt)));
+ size_t l = strlen (TREE_STRING_POINTER (rhs));
HOST_WIDE_INT a = int_size_in_bytes (TREE_TYPE (lhs));
if (a > 0 && (unsigned HOST_WIDE_INT) a > l)
{
