[PATCH]AArch64: check for vector mode in get_mask_mode [PR116074]

[Tamar Christina]

Hi All,

For historical reasons AArch64 has TI mode vector types but does not consider
TImode a vector mode.

What's happening in the PR is that get_vectype_for_scalar_type is returning
vector(1) TImode for a TImode scalar.  This then fails when we call
targetm.vectorize.get_mask_mode (vecmode).exists (&) on the TYPE_MODE.

I've checked other usages of get_mask_mode and none of them have anything that
would prevent this same issue from happening.  It only happens that normally
the vectorizer rejects the vector(1) type early, but in this case we get
further because the COND_EXPR hasn't been analyzed yet for a type.

I believe get_mask_mode shouldn't fault, and so this adds the check for vector
mode in the hook and returns nothing if it's not.  I did not add this to the
generic function because I believe this is an AArch64 quirk.

Bootstrapped Regtested on aarch64-none-linux-gnu and no issues.

Ok for master?

Thanks,
Tamar

gcc/ChangeLog:

        PR target/116074
        * config/aarch64/aarch64.cc (aarch64_get_mask_mode): Check vector mode.

gcc/testsuite/ChangeLog:

        PR target/116074
        * g++.target/aarch64/pr116074.C: New test.

---
diff --git a/gcc/config/aarch64/aarch64.cc b/gcc/config/aarch64/aarch64.cc
index 
355ab97891cf0a7d487fa4c69ae23a5f75897851..045ac0e09b0eaa14935db3924798402c9dd1947c
 100644
--- a/gcc/config/aarch64/aarch64.cc
+++ b/gcc/config/aarch64/aarch64.cc
@@ -1870,6 +1870,9 @@ aarch64_sve_pred_mode (machine_mode mode)
 static opt_machine_mode
 aarch64_get_mask_mode (machine_mode mode)
 {
+  if (!VECTOR_MODE_P (mode))
+    return opt_machine_mode ();
+
   unsigned int vec_flags = aarch64_classify_vector_mode (mode);
   if (vec_flags & VEC_SVE_DATA)
     return aarch64_sve_pred_mode (mode);
diff --git a/gcc/testsuite/g++.target/aarch64/pr116074.C 
b/gcc/testsuite/g++.target/aarch64/pr116074.C
new file mode 100644
index 
0000000000000000000000000000000000000000..54cf561510c460499a816ab6a84603fc20a5f1e5
--- /dev/null
+++ b/gcc/testsuite/g++.target/aarch64/pr116074.C
@@ -0,0 +1,24 @@
+/* { dg-do compile } */
+/* { dg-additional-options "-O3" } */
+
+int m[40];
+
+template <typename k> struct j {
+  int length;
+  k *e;
+  void operator[](int) {
+    if (length)
+      __builtin___memcpy_chk(m, m+3, sizeof (k), -1);
+  }
+};
+
+j<j<int>> o;
+
+int *q;
+
+void ao(int i) {
+  for (; i > 0; i--) {
+    o[1];
+    *q = 1;
+  }
+}




-- 

diff --git a/gcc/config/aarch64/aarch64.cc b/gcc/config/aarch64/aarch64.cc
index 355ab97891cf0a7d487fa4c69ae23a5f75897851..045ac0e09b0eaa14935db3924798402c9dd1947c 100644
--- a/gcc/config/aarch64/aarch64.cc
+++ b/gcc/config/aarch64/aarch64.cc
@@ -1870,6 +1870,9 @@ aarch64_sve_pred_mode (machine_mode mode)
 static opt_machine_mode
 aarch64_get_mask_mode (machine_mode mode)
 {
+  if (!VECTOR_MODE_P (mode))
+    return opt_machine_mode ();
+
   unsigned int vec_flags = aarch64_classify_vector_mode (mode);
   if (vec_flags & VEC_SVE_DATA)
     return aarch64_sve_pred_mode (mode);
diff --git a/gcc/testsuite/g++.target/aarch64/pr116074.C b/gcc/testsuite/g++.target/aarch64/pr116074.C
new file mode 100644
index 0000000000000000000000000000000000000000..54cf561510c460499a816ab6a84603fc20a5f1e5
--- /dev/null
+++ b/gcc/testsuite/g++.target/aarch64/pr116074.C
@@ -0,0 +1,24 @@
+/* { dg-do compile } */
+/* { dg-additional-options "-O3" } */
+
+int m[40];
+
+template <typename k> struct j {
+  int length;
+  k *e;
+  void operator[](int) {
+    if (length)
+      __builtin___memcpy_chk(m, m+3, sizeof (k), -1);
+  }
+};
+
+j<j<int>> o;
+
+int *q;
+
+void ao(int i) {
+  for (; i > 0; i--) {
+    o[1];
+    *q = 1;
+  }
+}