[llvm] [SPIRV] Add reads from image buffer for shaders. (PR #115178)

[Steven Perron via llvm-commits]

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@@ -0,0 +1,66 @@
+; RUN: llc -O0 -verify-machineinstrs -mtriple=spirv-vulkan-library %s -o - | FileCheck %s
+; RUN: %if spirv-tools %{ llc -O0 -mtriple=spirv-vulkan-library %s -o - -filetype=obj | spirv-val %}
+
+; CHECK-NOT: OpCapability StorageImageReadWithoutFormat
+
+; CHECK-DAG: OpDecorate [[IntBufferVar:%[0-9]+]] DescriptorSet 16
+; CHECK-DAG: OpDecorate [[IntBufferVar]] Binding 7
+
+; CHECK-DAG: [[int:%[0-9]+]] = OpTypeInt 32 0
+; CHECK-DAG: [[zero:%[0-9]+]] = OpConstant [[int]] 0
+; CHECK-DAG: [[v4_int:%[0-9]+]] = OpTypeVector [[int]] 4
+; CHECK-DAG: [[v2_int:%[0-9]+]] = OpTypeVector [[int]] 2
+; CHECK-DAG: [[RWBufferTypeInt:%[0-9]+]] = OpTypeImage [[int]] Buffer 2 0 0 2 R32i {{$}}
+; CHECK-DAG: [[IntBufferPtrType:%[0-9]+]] = OpTypePointer UniformConstant [[RWBufferTypeInt]]
+; CHECK-DAG: [[IntBufferVar]] = OpVariable [[IntBufferPtrType]] UniformConstant
+
+; CHECK: {{%[0-9]+}} = OpFunction {{%[0-9]+}} DontInline {{%[0-9]+}}
+; CHECK-NEXT: OpLabel
+define void @RWBufferLoad_Vec4_I32() #0 {
+; CHECK: [[buffer:%[0-9]+]] = OpLoad [[RWBufferTypeInt]] [[IntBufferVar]]
+  %buffer0 = call target("spirv.Image", i32, 5, 2, 0, 0, 2, 24)
+      @llvm.spv.handle.fromBinding.tspirv.Image_i32_5_2_0_0_2_24(
+          i32 16, i32 7, i32 1, i32 0, i1 false)
+
+; CHECK: OpImageRead [[v4_int]] [[buffer]] [[zero]]
+  %data0 = call <4 x i32> @llvm.spv.typedBufferLoad(
+      target("spirv.Image", i32, 5, 2, 0, 0, 2, 24) %buffer0, i32 0)
+
+  ret void
+}
+
+; CHECK: {{%[0-9]+}} = OpFunction {{%[0-9]+}} DontInline {{%[0-9]+}}
+; CHECK-NEXT: OpLabel
+define void @RWBufferLoad_I32() #0 {
+; CHECK: [[buffer:%[0-9]+]] = OpLoad [[RWBufferTypeInt]] [[IntBufferVar]]
+  %buffer1 = call target("spirv.Image", i32, 5, 2, 0, 0, 2, 24)
+      @llvm.spv.handle.fromBinding.tspirv.Image_i32_5_2_0_0_2_24(
+          i32 16, i32 7, i32 1, i32 0, i1 false)
+
+; CHECK: [[V:%[0-9]+]] = OpImageRead [[v4_int]] [[buffer]] [[zero]]
+; CHECK: OpCompositeExtract [[int]] [[V]] 0
+  %data1 = call i32 @llvm.spv.typedBufferLoad(
+      target("spirv.Image", i32, 5, 2, 0, 0, 2, 24) %buffer1, i32 0)
+
+  ret void
+}
+
+; CHECK: {{%[0-9]+}} = OpFunction {{%[0-9]+}} DontInline {{%[0-9]+}}
+; CHECK-NEXT: OpLabel
+define void @RWBufferLoad_Vec2_I32() #0 {
+; CHECK: [[buffer:%[0-9]+]] = OpLoad [[RWBufferTypeInt]] [[IntBufferVar]]
+  %buffer0 = call target("spirv.Image", i32, 5, 2, 0, 0, 2, 24)
+      @llvm.spv.handle.fromBinding.tspirv.Image_i32_5_2_0_0_2_24(
+          i32 16, i32 7, i32 1, i32 0, i1 false)
----------------
s-perron wrote:

That is really a test for `handle.fromBinding`. I believe I have that covered in existing testing:

https://github.com/llvm/llvm-project/blob/60972a893e2bf915f6ff043c9396dea9619456fb/llvm/test/CodeGen/SPIRV/hlsl-resources/HlslBufferLoad.ll#L4-L7

and 

https://github.com/llvm/llvm-project/blob/60972a893e2bf915f6ff043c9396dea9619456fb/llvm/test/CodeGen/SPIRV/hlsl-resources/InputAttachmentImageDynIdx.ll#L9-L10

Is that enough, or do you need more?

https://github.com/llvm/llvm-project/pull/115178