[clang] [Clang][OpenCL] Mark scalar loads from constant address space invariant (PR #218356)

[Matt Arsenault via cfe-commits]

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@@ -0,0 +1,24 @@
+// REQUIRES: amdgpu-registered-target
+// RUN: %clang_cc1 -triple amdgcn-amd-amdhsa -cl-std=CL2.0 -O0 -emit-llvm -o - %s | FileCheck %s --check-prefix=AMDGCN
+// RUN: %clang_cc1 -triple spir64-unknown-unknown -cl-std=CL2.0 -O0 -emit-llvm -o - %s | FileCheck %s --check-prefix=SPIR
+
+kernel void constant_load(global int *out, constant int *in) {
+  out[0] = in[0];
+}
+
+// AMDGCN-LABEL: define{{.*}}@constant_load(
+// AMDGCN: load i32, ptr addrspace(4) %{{.*}}, align 4, !invariant.load [[INVARIANT:![0-9]+]]
+// SPIR-LABEL: define{{.*}}@constant_load(
+// SPIR: load i32, ptr addrspace(2) %{{.*}}, align 4, !invariant.load [[INVARIANT:![0-9]+]]
+
+kernel void global_const_load(global int *out, global const int *in) {
+  out[0] = in[0];
+}
+
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arsenm wrote:

Also check the Cuda case? 

https://github.com/llvm/llvm-project/pull/218356