[llvm] [DirectX] Introduce the DXILResourceAccess pass (PR #116726)

[Justin Bogner via llvm-commits]

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@@ -0,0 +1,103 @@
+; RUN: opt -S -dxil-resource-access %s | FileCheck %s
+
+target triple = "dxil-pc-shadermodel6.6-compute"
+
+; CHECK-LABEL: define void @store_float4
+define void @store_float4(<4 x float> %data, i32 %index, i32 %elemindex) {
+  %buffer = call target("dx.TypedBuffer", <4 x float>, 1, 0, 0)
+      @llvm.dx.handle.fromBinding.tdx.TypedBuffer_v4f32_1_0_0(
+          i32 0, i32 0, i32 1, i32 0, i1 false)
+
+  ; CHECK-NOT: @llvm.dx.resource.getpointer
+  %ptr = call ptr @llvm.dx.resource.getpointer(
+      target("dx.TypedBuffer", <4 x float>, 1, 0, 0) %buffer, i32 %index)
+
+  ; Store the whole value
+  ; CHECK: call void @llvm.dx.typedBufferStore.tdx.TypedBuffer_v4f32_1_0_0t.v4f32(target("dx.TypedBuffer", <4 x float>, 1, 0, 0) %buffer, i32 %index, <4 x float> %data)
+  store <4 x float> %data, ptr %ptr
+
+  ; Store just the .x component
+  %scalar = extractelement <4 x float> %data, i32 0
+  ; CHECK: %[[LOAD:.*]] = call <4 x float> @llvm.dx.typedBufferLoad.v4f32.tdx.TypedBuffer_v4f32_1_0_0t(target("dx.TypedBuffer", <4 x float>, 1, 0, 0) %buffer, i32 %index)
+  ; CHECK: %[[INSERT:.*]] = insertelement <4 x float> %[[LOAD]], float %scalar, i32 0
+  ; CHECK: call void @llvm.dx.typedBufferStore.tdx.TypedBuffer_v4f32_1_0_0t.v4f32(target("dx.TypedBuffer", <4 x float>, 1, 0, 0) %buffer, i32 %index, <4 x float> %[[INSERT]])
+  store float %scalar, ptr %ptr
+
+  ; Store just the .y component
+  ; CHECK: %[[LOAD:.*]] = call <4 x float> @llvm.dx.typedBufferLoad.v4f32.tdx.TypedBuffer_v4f32_1_0_0t(target("dx.TypedBuffer", <4 x float>, 1, 0, 0) %buffer, i32 %index)
+  ; CHECK: %[[INSERT:.*]] = insertelement <4 x float> %[[LOAD]], float %scalar, i32 1
+  ; CHECK: call void @llvm.dx.typedBufferStore.tdx.TypedBuffer_v4f32_1_0_0t.v4f32(target("dx.TypedBuffer", <4 x float>, 1, 0, 0) %buffer, i32 %index, <4 x float> %[[INSERT]])
+  %y_ptr = getelementptr inbounds i8, ptr %ptr, i32 4
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bogner wrote:

This is intentional. LLVM seems to canonicalize some geps to work on `i8` like this (I think as part of the work for the proposal to replace gep with a generic "pointer add"). I added the test case because I was seeing this come out of the frontend.

https://github.com/llvm/llvm-project/pull/116726