[clang] [HLSL] Add RWStructuredBuffer definition to HLSLExternalSemaSource (PR #113477)

[Helena Kotas via cfe-commits]

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@@ -0,0 +1,70 @@
+// RUN: %clang_cc1 -triple dxil-pc-shadermodel6.2-compute -finclude-default-header -fnative-half-type -emit-llvm -o - %s | FileCheck %s
+
+// NOTE: The number in type name and whether the struct is packed or not will mostly
+// likely change once subscript operators are properly implemented (llvm/llvm-project#95956) 
+// and theinterim field of the contained type is removed.
+
+// CHECK: %"class.hlsl::RWStructuredBuffer" = type <{ target("dx.RawBuffer", i16, 1, 0)
+// CHECK: %"class.hlsl::RWStructuredBuffer.0" = type <{ target("dx.RawBuffer", i16, 1, 0)
+// CHECK: %"class.hlsl::RWStructuredBuffer.2" = type { target("dx.RawBuffer", i32, 1, 0)
+// CHECK: %"class.hlsl::RWStructuredBuffer.3" = type { target("dx.RawBuffer", i32, 1, 0)
+// CHECK: %"class.hlsl::RWStructuredBuffer.4" = type { target("dx.RawBuffer", i64, 1, 0)
+// CHECK: %"class.hlsl::RWStructuredBuffer.5" = type { target("dx.RawBuffer", i64, 1, 0)
+// CHECK: %"class.hlsl::RWStructuredBuffer.6" = type <{ target("dx.RawBuffer", half, 1, 0) 
+// CHECK: %"class.hlsl::RWStructuredBuffer.8" = type { target("dx.RawBuffer", float, 1, 0)
+// CHECK: %"class.hlsl::RWStructuredBuffer.9" = type { target("dx.RawBuffer", double, 1, 0)
+// CHECK: %"class.hlsl::RWStructuredBuffer.10" = type { target("dx.RawBuffer", <4 x i16>, 1, 0)
+// CHECK: %"class.hlsl::RWStructuredBuffer.11" = type { target("dx.RawBuffer", <3 x i32>, 1, 0)
+// CHECK: %"class.hlsl::RWStructuredBuffer.12" = type { target("dx.RawBuffer", <2 x half>, 1, 0)
+// CHECK: %"class.hlsl::RWStructuredBuffer.13" = type { target("dx.RawBuffer", <3 x float>, 1, 0)
+
+RWStructuredBuffer<int16_t> BufI16;
+RWStructuredBuffer<uint16_t> BufU16;
+RWStructuredBuffer<int> BufI32;
+RWStructuredBuffer<uint> BufU32;
+RWStructuredBuffer<int64_t> BufI64;
+RWStructuredBuffer<uint64_t> BufU64;
+RWStructuredBuffer<half> BufF16;
+RWStructuredBuffer<float> BufF32;
+RWStructuredBuffer<double> BufF64;
+RWStructuredBuffer< vector<int16_t, 4> > BufI16x4;
+RWStructuredBuffer< vector<uint, 3> > BufU32x3;
+RWStructuredBuffer<half2> BufF16x2;
+RWStructuredBuffer<float3> BufF32x3;
+// TODO: RWStructuredBuffer<snorm half> BufSNormF16;
+// TODO: RWStructuredBuffer<unorm half> BufUNormF16;
+// TODO: RWStructuredBuffer<snorm float> BufSNormF32;
+// TODO: RWStructuredBuffer<unorm float> BufUNormF32;
+// TODO: RWStructuredBuffer<snorm double> BufSNormF64;
+// TODO: RWStructuredBuffer<unorm double> BufUNormF64;
+
+[numthreads(1,1,1)]
+void main(int GI : SV_GroupIndex) {
+  BufI16[GI] = 0;
+  BufU16[GI] = 0;
+  BufI32[GI] = 0;
+  BufU32[GI] = 0;
+  BufI64[GI] = 0;
+  BufU64[GI] = 0;
+  BufF16[GI] = 0;
+  BufF32[GI] = 0;
+  BufF64[GI] = 0;
+  BufI16x4[GI] = 0;
+  BufU32x3[GI] = 0;
+  BufF16x2[GI] = 0;
+  BufF32x3[GI] = 0;
+}
+
+// CHECK: !{{[0-9]+}} = !{ptr @BufI16, i32 10, i32 2,
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hekota wrote:

Yes, these are stable. The first number is the [ResourceKind](https://github.com/llvm/llvm-project/blob/33363521ca24f912cc25530f6cecbca53acce8a3/llvm/include/llvm/Support/DXILABI.h#L34) and the second is the [ElementType](https://github.com/llvm/llvm-project/blob/33363521ca24f912cc25530f6cecbca53acce8a3/llvm/include/llvm/Support/DXILABI.h#L58).

Also, I believe these will away once we [remove the HLSLResource](https://github.com/llvm/llvm-project/issues/104862) attribute.

https://github.com/llvm/llvm-project/pull/113477