https://gcc.gnu.org/g:046aeffba336295fbdaf0e1ecf64b582d08f0aa6
commit r11-11419-g046aeffba336295fbdaf0e1ecf64b582d08f0aa6
Author: Andrew Pinski <quic_apin...@quicinc.com>
Date: Tue Feb 20 13:38:28 2024 -0800
c++/c-common: Fix convert_vector_to_array_for_subscript for qualified
vector types [PR89224]
After r7-987-gf17a223de829cb, the access for the elements of a vector type
would lose the qualifiers.
So if we had `constvector[0]`, the type of the element of the array would
not have const on it.
This was due to a missing build_qualified_type for the inner type of the
vector when building the array type.
We need to add back the call to build_qualified_type and now the access has
the correct qualifiers. So the
overloads and even if it is a lvalue or rvalue is correctly done.
Note we correctly now reject the testcase gcc.dg/pr83415.c which was
incorrectly accepted after r7-987-gf17a223de829cb.
Built and tested for aarch64-linux-gnu.
PR c++/89224
gcc/c-family/ChangeLog:
* c-common.c (convert_vector_to_array_for_subscript): Call
build_qualified_type
for the inner type.
gcc/cp/ChangeLog:
* constexpr.c (cxx_eval_array_reference): Compare main variants
for the vector/array types instead of the types directly.
gcc/testsuite/ChangeLog:
* g++.dg/torture/vector-subaccess-1.C: New test.
* gcc.dg/pr83415.c: Change warning to error.
Signed-off-by: Andrew Pinski <quic_apin...@quicinc.com>
(cherry picked from commit 4421d35167b3083e0f2e4c84c91fded09a30cf22)
Diff:
---
gcc/c-family/c-common.c | 7 ++++++-
gcc/cp/constexpr.c | 3 ++-
gcc/testsuite/g++.dg/torture/vector-subaccess-1.C | 23 +++++++++++++++++++++++
gcc/testsuite/gcc.dg/pr83415.c | 2 +-
4 files changed, 32 insertions(+), 3 deletions(-)
diff --git a/gcc/c-family/c-common.c b/gcc/c-family/c-common.c
index 9417b7fb4d1f..ae3ef89b05cb 100644
--- a/gcc/c-family/c-common.c
+++ b/gcc/c-family/c-common.c
@@ -8274,6 +8274,7 @@ convert_vector_to_array_for_subscript (location_t loc,
if (gnu_vector_type_p (TREE_TYPE (*vecp)))
{
tree type = TREE_TYPE (*vecp);
+ tree newitype;
ret = !lvalue_p (*vecp);
@@ -8288,8 +8289,12 @@ convert_vector_to_array_for_subscript (location_t loc,
for function parameters. */
c_common_mark_addressable_vec (*vecp);
+ /* Make sure qualifiers are copied from the vector type to the new
element
+ of the array type. */
+ newitype = build_qualified_type (TREE_TYPE (type), TYPE_QUALS (type));
+
*vecp = build1 (VIEW_CONVERT_EXPR,
- build_array_type_nelts (TREE_TYPE (type),
+ build_array_type_nelts (newitype,
TYPE_VECTOR_SUBPARTS (type)),
*vecp);
}
diff --git a/gcc/cp/constexpr.c b/gcc/cp/constexpr.c
index 38f684144f0c..eb18b5b35378 100644
--- a/gcc/cp/constexpr.c
+++ b/gcc/cp/constexpr.c
@@ -3767,7 +3767,8 @@ cxx_eval_array_reference (const constexpr_ctx *ctx, tree
t,
if (!lval
&& TREE_CODE (ary) == VIEW_CONVERT_EXPR
&& VECTOR_TYPE_P (TREE_TYPE (TREE_OPERAND (ary, 0)))
- && TREE_TYPE (t) == TREE_TYPE (TREE_TYPE (TREE_OPERAND (ary, 0))))
+ && (TYPE_MAIN_VARIANT (TREE_TYPE (t))
+ == TYPE_MAIN_VARIANT (TREE_TYPE (TREE_TYPE (TREE_OPERAND (ary, 0))))))
ary = TREE_OPERAND (ary, 0);
tree oldidx = TREE_OPERAND (t, 1);
diff --git a/gcc/testsuite/g++.dg/torture/vector-subaccess-1.C
b/gcc/testsuite/g++.dg/torture/vector-subaccess-1.C
new file mode 100644
index 000000000000..0c8958a4e034
--- /dev/null
+++ b/gcc/testsuite/g++.dg/torture/vector-subaccess-1.C
@@ -0,0 +1,23 @@
+/* PR c++/89224 */
+
+/* The access of `vector[i]` has the same qualifiers as the original
+ vector which was missing. */
+
+typedef __attribute__((vector_size(16))) unsigned char Int8x8_t;
+
+template <class T>
+void g(T &x) {
+ __builtin_abort();
+}
+template <class T>
+void g(const T &x) {
+ __builtin_exit(0);
+}
+void f(const Int8x8_t x) {
+ g(x[0]);
+}
+int main(void)
+{
+ Int8x8_t x ={};
+ f(x);
+}
diff --git a/gcc/testsuite/gcc.dg/pr83415.c b/gcc/testsuite/gcc.dg/pr83415.c
index 5934c16d97cb..2fc85031505d 100644
--- a/gcc/testsuite/gcc.dg/pr83415.c
+++ b/gcc/testsuite/gcc.dg/pr83415.c
@@ -7,6 +7,6 @@ int
main (int argc, short *argv[])
{
int i = argc;
- y[i] = 7 - i; /* { dg-warning "read-only" } */
+ y[i] = 7 - i; /* { dg-error "read-only" } */
return 0;
}
