[PATCH]AArch64: Do not allow SIMD clones with simdlen 1 [PR113552]

[Tamar Christina]

Hi All,

The AArch64 vector PCS does not allow simd calls with simdlen 1,
however due to a bug we currently do allow it for num == 0.

This causes us to emit a symbol that doesn't exist and we fail to link.

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

Ok for master? and for backport to GCC 13,12,11?

Thanks,
Tamar



gcc/ChangeLog:

        PR tree-optimization/113552
        * config/aarch64/aarch64.cc
        (aarch64_simd_clone_compute_vecsize_and_simdlen): Block simdlen 1.

gcc/testsuite/ChangeLog:

        PR tree-optimization/113552
        * gcc.target/aarch64/pr113552.c: New test.
        * gcc.target/aarch64/simd_pcs_attribute-3.c: Remove bogus check.

--- inline copy of patch -- 
diff --git a/gcc/config/aarch64/aarch64.cc b/gcc/config/aarch64/aarch64.cc
index 
e6bd3fd0bb42c70603d5335402b89c9deeaf48d8..a2fc1a5d9d27e9d837e4d616e3feaf38f7272b4f
 100644
--- a/gcc/config/aarch64/aarch64.cc
+++ b/gcc/config/aarch64/aarch64.cc
@@ -28620,7 +28620,8 @@ aarch64_simd_clone_compute_vecsize_and_simdlen (struct 
cgraph_node *node,
   if (known_eq (clonei->simdlen, 0U))
     {
       simdlen = exact_div (poly_uint64 (64), nds_elt_bits);
-      simdlens.safe_push (simdlen);
+      if (known_ne (simdlen, 1U))
+       simdlens.safe_push (simdlen);
       simdlens.safe_push (simdlen * 2);
     }
   else
diff --git a/gcc/testsuite/gcc.target/aarch64/pr113552.c 
b/gcc/testsuite/gcc.target/aarch64/pr113552.c
new file mode 100644
index 
0000000000000000000000000000000000000000..9c96b061ed2b4fcc57e58925277f74d14f79c51f
--- /dev/null
+++ b/gcc/testsuite/gcc.target/aarch64/pr113552.c
@@ -0,0 +1,17 @@
+/* { dg-do compile } */
+/* { dg-options "-Ofast -march=armv8-a" } */
+
+__attribute__ ((__simd__ ("notinbranch"), const))
+double cos (double);
+
+void foo (float *a, double *b)
+{
+    for (int i = 0; i < 12; i+=3)
+      {
+        b[i] = cos (5.0 * a[i]);
+        b[i+1] = cos (5.0 * a[i+1]);
+        b[i+2] = cos (5.0 * a[i+2]);
+      }
+}
+
+/* { dg-final { scan-assembler-times {bl\t_ZGVnN2v_cos} 6 } } */
diff --git a/gcc/testsuite/gcc.target/aarch64/simd_pcs_attribute-3.c 
b/gcc/testsuite/gcc.target/aarch64/simd_pcs_attribute-3.c
index 
95f6a6803e889c02177ef10972962ed62d2095eb..661764b3d4a89e08951a7a3c0495d5b7ba7f0871
 100644
--- a/gcc/testsuite/gcc.target/aarch64/simd_pcs_attribute-3.c
+++ b/gcc/testsuite/gcc.target/aarch64/simd_pcs_attribute-3.c
@@ -18,7 +18,5 @@ double foo(double x)
 }
 
 /* { dg-final { scan-assembler-not {\.variant_pcs\tfoo} } } */
-/* { dg-final { scan-assembler-times {\.variant_pcs\t_ZGVnM1v_foo} 1 } } */
 /* { dg-final { scan-assembler-times {\.variant_pcs\t_ZGVnM2v_foo} 1 } } */
-/* { dg-final { scan-assembler-times {\.variant_pcs\t_ZGVnN1v_foo} 1 } } */
 /* { dg-final { scan-assembler-times {\.variant_pcs\t_ZGVnN2v_foo} 1 } } */




-- 

diff --git a/gcc/config/aarch64/aarch64.cc b/gcc/config/aarch64/aarch64.cc
index 
e6bd3fd0bb42c70603d5335402b89c9deeaf48d8..a2fc1a5d9d27e9d837e4d616e3feaf38f7272b4f
 100644
--- a/gcc/config/aarch64/aarch64.cc
+++ b/gcc/config/aarch64/aarch64.cc
@@ -28620,7 +28620,8 @@ aarch64_simd_clone_compute_vecsize_and_simdlen (struct 
cgraph_node *node,
   if (known_eq (clonei->simdlen, 0U))
     {
       simdlen = exact_div (poly_uint64 (64), nds_elt_bits);
-      simdlens.safe_push (simdlen);
+      if (known_ne (simdlen, 1U))
+       simdlens.safe_push (simdlen);
       simdlens.safe_push (simdlen * 2);
     }
   else
diff --git a/gcc/testsuite/gcc.target/aarch64/pr113552.c 
b/gcc/testsuite/gcc.target/aarch64/pr113552.c
new file mode 100644
index 
0000000000000000000000000000000000000000..9c96b061ed2b4fcc57e58925277f74d14f79c51f
--- /dev/null
+++ b/gcc/testsuite/gcc.target/aarch64/pr113552.c
@@ -0,0 +1,17 @@
+/* { dg-do compile } */
+/* { dg-options "-Ofast -march=armv8-a" } */
+
+__attribute__ ((__simd__ ("notinbranch"), const))
+double cos (double);
+
+void foo (float *a, double *b)
+{
+    for (int i = 0; i < 12; i+=3)
+      {
+        b[i] = cos (5.0 * a[i]);
+        b[i+1] = cos (5.0 * a[i+1]);
+        b[i+2] = cos (5.0 * a[i+2]);
+      }
+}
+
+/* { dg-final { scan-assembler-times {bl\t_ZGVnN2v_cos} 6 } } */
diff --git a/gcc/testsuite/gcc.target/aarch64/simd_pcs_attribute-3.c 
b/gcc/testsuite/gcc.target/aarch64/simd_pcs_attribute-3.c
index 
95f6a6803e889c02177ef10972962ed62d2095eb..661764b3d4a89e08951a7a3c0495d5b7ba7f0871
 100644
--- a/gcc/testsuite/gcc.target/aarch64/simd_pcs_attribute-3.c
+++ b/gcc/testsuite/gcc.target/aarch64/simd_pcs_attribute-3.c
@@ -18,7 +18,5 @@ double foo(double x)
 }
 
 /* { dg-final { scan-assembler-not {\.variant_pcs\tfoo} } } */
-/* { dg-final { scan-assembler-times {\.variant_pcs\t_ZGVnM1v_foo} 1 } } */
 /* { dg-final { scan-assembler-times {\.variant_pcs\t_ZGVnM2v_foo} 1 } } */
-/* { dg-final { scan-assembler-times {\.variant_pcs\t_ZGVnN1v_foo} 1 } } */
 /* { dg-final { scan-assembler-times {\.variant_pcs\t_ZGVnN2v_foo} 1 } } */