[clang] [HLSL] Implement RWBuffer::operator[] via __builtin_hlsl_resource_getpointer (PR #117017)

[Justin Bogner via cfe-commits]

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@@ -6,14 +6,17 @@ RasterizerOrderedStructuredBuffer<int> Out2;
 
 [numthreads(1,1,1)]
 void main(unsigned GI : SV_GroupIndex) {
+  // CHECK: define void @main()
+
+  // CHECK: %[[INPTR:.*]] = call noundef nonnull align 4 dereferenceable(4) ptr @llvm.dx.resource.getpointer.p0.tdx.RawBuffer_i32_0_0t(target("dx.RawBuffer", i32, 0, 0) %{{.*}}, i32 %{{.*}})
+  // CHECK: %[[LOAD:.*]] = load i32, ptr %[[INPTR]]
+  // CHECK: %[[OUT1PTR:.*]] = call noundef nonnull align 4 dereferenceable(4) ptr @llvm.dx.resource.getpointer.p0.tdx.RawBuffer_i32_1_0t(target("dx.RawBuffer", i32, 1, 0) %{{.*}}, i32 %{{.*}})
+  // CHECK: store i32 %[[LOAD]], ptr %[[OUT1PTR]]
   Out1[GI] = In[GI];
+
+  // CHECK: %[[INPTR:.*]] = call noundef nonnull align 4 dereferenceable(4) ptr @llvm.dx.resource.getpointer.p0.tdx.RawBuffer_i32_0_0t(target("dx.RawBuffer", i32, 0, 0) %{{.*}}, i32 %{{.*}})
+  // CHECK: %[[LOAD:.*]] = load i32, ptr %[[INPTR]]
+  // CHECK: %[[OUT2PTR:.*]] = call noundef nonnull align 4 dereferenceable(4) ptr @llvm.dx.resource.getpointer.p0.tdx.RawBuffer_i32_1_1t(target("dx.RawBuffer", i32, 1, 1) %{{.*}}, i32 %{{.*}})
+  // CHECK: store i32 %[[LOAD]], ptr %[[OUT2PTR]]
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bogner wrote:

I've commented in the other PR - I think this highlights that we will need to make sure we change this to use an address space for the device memory sooner rather than later, as mixing pointers between resource types would cause all sorts of trouble.

https://github.com/llvm/llvm-project/pull/117017