Re: [PATCH] test: Isolate slp-1.c check of target supports vect_strided5

[Andrew Stubbs]

On 15/09/2023 10:16, Juzhe-Zhong wrote:
This test failed in RISC-V:
FAIL: gcc.dg/vect/slp-1.c -flto -ffat-lto-objects  scan-tree-dump-times vect 
"vectorizing stmts using SLP" 4
FAIL: gcc.dg/vect/slp-1.c scan-tree-dump-times vect "vectorizing stmts using 
SLP" 4
Because this loop:
   /* SLP with unrolling by 8.  */
   for (i = 0; i < N; i++)
     {
       out[i*5] = 8;
       out[i*5 + 1] = 7;
       out[i*5 + 2] = 81;
       out[i*5 + 3] = 28;
       out[i*5 + 4] = 18;
     }

is using vect_load_lanes with array size = 5.
instead of SLP.

When we adjust the COST of LANES load store, then it will use SLP.

gcc/testsuite/ChangeLog:

        * gcc.dg/vect/slp-1.c: Add vect_stried5.

---
  gcc/testsuite/gcc.dg/vect/slp-1.c | 4 ++--
  1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/gcc/testsuite/gcc.dg/vect/slp-1.c 
b/gcc/testsuite/gcc.dg/vect/slp-1.c
index 82e4f6469fb..d4a13f12df6 100644
--- a/gcc/testsuite/gcc.dg/vect/slp-1.c
+++ b/gcc/testsuite/gcc.dg/vect/slp-1.c
@@ -122,5 +122,5 @@ int main (void)
  }
  
  /* { dg-final { scan-tree-dump-times "vectorized 4 loops" 1 "vect"  } } */
-/* { dg-final { scan-tree-dump-times "vectorizing stmts using SLP" 4 "vect" } 
} */
-
+/* { dg-final { scan-tree-dump-times "vectorizing stmts using SLP" 4 "vect" { 
target {! vect_strided5 } } } } */
+/* { dg-final { scan-tree-dump-times "vectorizing stmts using SLP" 3 "vect" { 
target vect_strided5 } } } */

This patch causes a test regression on amdgcn because vect_strided5 is 
true (because check_effective_target_vect_fully_masked is true), but the 
testcase still gives the message 4 times. Perhaps because amdgcn uses 
masking and not vect_load_lanes?

Andrew