[llvm] [DirectX] Add `llvm.dx.resource.getdimensions` intrinsic and lowering to DXIL (PR #161753)

[Joshua Batista via llvm-commits]

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@@ -0,0 +1,34 @@
+; RUN: opt -S -dxil-op-lower %s | FileCheck %s
+
+target triple = "dxil-pc-shadermodel6.6-compute"
+
+define i32 @test_getdimensions_no_mips() {
+  ; CHECK: [[HANDLE1:%.*]] = call %dx.types.Handle @dx.op.createHandleFromBinding(i32 217, 
+  ; CHECK-NEXT: [[ANNOT_HANDLE1:%.*]] = call %dx.types.Handle @dx.op.annotateHandle(i32 216, %dx.types.Handle [[HANDLE1]]
+  %handle1 = call target("dx.TypedBuffer", <4 x float>, 0, 0, 0) @llvm.dx.resource.handlefrombinding(i32 0, i32 0, i32 1, i32 0, ptr null)
+
+  ; CHECK-NEXT: [[RETVAL1:%.*]] = call %dx.types.Dimensions @dx.op.getDimensions(i32 72, %dx.types.Handle [[ANNOT_HANDLE1]], i32 undef)
+  %1 = call { i32, i32, i32, i32 } @llvm.dx.resource.getdimensions.tdx.RawBuffer_i32_1_0t(target("dx.TypedBuffer", <4 x float>, 0, 0, 0) %handle1, i32 poison)
+  
+  ; CHECK-NEXT: %[[DIM1:.*]] = extractvalue %dx.types.Dimensions [[RETVAL1]], 0
+  %2 = extractvalue { i32, i32, i32, i32 } %1, 0
+  
+  ; CHECK-NEXT: ret i32 %[[DIM1]]
+  ret i32 %2
+}
+
+
+define i32 @test_getdimensions_with_0_mips() {
+  ; CHECK: [[HANDLE2:%.*]] = call %dx.types.Handle @dx.op.createHandleFromBinding(i32 217, 
+  ; CHECK-NEXT: [[ANNOT_HANDLE2:%.*]] = call %dx.types.Handle @dx.op.annotateHandle(i32 216, %dx.types.Handle [[HANDLE2]]
+  %handle1 = call target("dx.RawBuffer", float, 0, 0) @llvm.dx.resource.handlefrombinding(i32 0, i32 0, i32 1, i32 0, ptr null)
+
+  ; CHECK-NEXT: [[RETVAL2:%.*]] = call %dx.types.Dimensions @dx.op.getDimensions(i32 72, %dx.types.Handle [[ANNOT_HANDLE2]], i32 0)
+  %1 = call { i32, i32, i32, i32 } @llvm.dx.resource.getdimensions.tdx.RawBuffer_i32_1_0t(target("dx.RawBuffer", float, 0, 0) %handle1, i32 0)
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bob80905 wrote:

Why is there a different number of args to target here, compared to the 5 args above?

https://github.com/llvm/llvm-project/pull/161753