[Polly] Do not use -O3 pipeline for single pass test.

GitOrigin-RevId: 11511ee3438ad319ae99270d371285a30d8839d6
diff --git a/test/GPGPU/spir-codegen.ll b/test/GPGPU/spir-codegen.ll
index 26373e6..a464bfd 100644
--- a/test/GPGPU/spir-codegen.ll
+++ b/test/GPGPU/spir-codegen.ll
@@ -1,4 +1,4 @@
-; RUN: opt %loadPolly -O3 -polly -polly-target=gpu \
+; RUN: opt %loadPolly -polly-codegen-ppcg -polly-target=gpu \
 ; RUN: -polly-gpu-arch=spir32 \
 ; RUN: -polly-acc-dump-kernel-ir -polly-process-unprofitable -disable-output -enable-new-pm=0 < %s | \
 ; RUN: FileCheck %s