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

[Helena Kotas via llvm-commits]

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@@ -0,0 +1,35 @@
+; RUN: opt -S -dxil-resource-access %s | FileCheck %s
+
+target triple = "dxil-pc-shadermodel6.6-compute"
+
+declare void @use_float4(<4 x float>)
+declare void @use_float(<4 x float>)
+
+; CHECK-LABEL: define void @load_float4
+define void @load_float4(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)
+
+  ; CHECK: %[[VALUE:.*]] = 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)
+  %vec_data = load <4 x float>, ptr %ptr
+  call void @use_float4(<4 x float> %vec_data)
+
+  ; CHECK: %[[VALUE:.*]] = 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: extractelement <4 x float> %[[VALUE]], i32 4
+  %y_ptr = getelementptr inbounds <4 x float>, ptr %ptr, i32 0, i32 4
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hekota wrote:

Is the `4` here byte offset, or an index of the `y` element, in which case it should be `1`? 

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