[llvm-branch-commits] [DirectX] Lower `@llvm.dx.typedBufferLoad` to DXIL ops (PR #104252)

[David Peixotto via llvm-branch-commits]

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@@ -0,0 +1,102 @@
+; RUN: opt -S -dxil-op-lower %s | FileCheck %s
+
+target triple = "dxil-pc-shadermodel6.6-compute"
+
+declare void @scalar_user(float)
+declare void @vector_user(<4 x float>)
+
+define void @loadfloats() {
+  ; CHECK: [[BIND:%.*]] = call %dx.types.Handle @dx.op.createHandleFromBinding
+  ; CHECK: [[HANDLE:%.*]] = call %dx.types.Handle @dx.op.annotateHandle(i32 217, %dx.types.Handle [[BIND]]
+  %buffer = call target("dx.TypedBuffer", <4 x float>, 0, 0, 0)
+              @llvm.dx.handle.fromBinding.tdx.TypedBuffer_v4f32_0_0_0(
+                  i32 0, i32 0, i32 1, i32 0, i1 false)
+
+  ; The temporary casts should all have been cleaned up
+  ; CHECK-NOT: %dx.cast_handle
+
+  ; CHECK: [[DATA0:%.*]] = call %dx.types.ResRet.f32 @dx.op.bufferLoad.f32(i32 68, %dx.types.Handle [[HANDLE]], i32 0, i32 undef)
+  %data0 = call <4 x float> @llvm.dx.typedBufferLoad(
+             target("dx.TypedBuffer", <4 x float>, 0, 0, 0) %buffer, i32 0)
+
+  ; The extract order depends on the users, so don't enforce that here.
+  ; CHECK-DAG: extractvalue %dx.types.ResRet.f32 [[DATA0]], 0
+  %data0_0 = extractelement <4 x float> %data0, i32 0
+  ; CHECK-DAG: extractvalue %dx.types.ResRet.f32 [[DATA0]], 2
+  %data0_2 = extractelement <4 x float> %data0, i32 2
+
+  ; If all of the uses are extracts, we skip creating a vector
+  ; CHECK-NOT: insertelement
+  call void @scalar_user(float %data0_0)
+  call void @scalar_user(float %data0_2)
+
+  ; CHECK: [[DATA4:%.*]] = call %dx.types.ResRet.f32 @dx.op.bufferLoad.f32(i32 68, %dx.types.Handle [[HANDLE]], i32 4, i32 undef)
+  %data4 = call <4 x float> @llvm.dx.typedBufferLoad(
+             target("dx.TypedBuffer", <4 x float>, 0, 0, 0) %buffer, i32 4)
+
+  ; CHECK: extractvalue %dx.types.ResRet.f32 [[DATA4]], 0
+  ; CHECK: extractvalue %dx.types.ResRet.f32 [[DATA4]], 1
+  ; CHECK: extractvalue %dx.types.ResRet.f32 [[DATA4]], 2
+  ; CHECK: extractvalue %dx.types.ResRet.f32 [[DATA4]], 3
+  ; CHECK: insertelement <4 x float> undef
+  ; CHECK: insertelement <4 x float>
+  ; CHECK: insertelement <4 x float>
+  ; CHECK: insertelement <4 x float>
+  call void @vector_user(<4 x float> %data4)
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dmpots wrote:

I understand why you use a call here, but this is going to produce something that we cannot actually generate valid dxil for right? Should we have tests where we produce invalid dxil?

Maybe this is fine here because it is only lowering ops and we have some dxil validation later?

https://github.com/llvm/llvm-project/pull/104252