Implement the `InstanceID` HLSL Function

[farzonl]

• [ ] Implement InstanceID clang builtin,
• [ ] Link InstanceID clang builtin with hlsl_intrinsics.h
• [ ] Add sema checks for InstanceID to CheckHLSLBuiltinFunctionCall in SemaChecking.cpp
• [ ] Add codegen for InstanceID to EmitHLSLBuiltinExpr in CGBuiltin.cpp
• [ ] Add codegen tests to clang/test/CodeGenHLSL/builtins/InstanceID.hlsl
• [ ] Add sema tests to clang/test/SemaHLSL/BuiltIns/InstanceID-errors.hlsl
• [ ] Create the int_dx_InstanceID intrinsic in IntrinsicsDirectX.td
• [ ] Create the DXILOpMapping of int_dx_InstanceID to 141 in DXIL.td
• [ ] Create the InstanceID.ll and InstanceID_errors.ll tests in llvm/test/CodeGen/DirectX/
• [ ] Create the int_spv_InstanceID intrinsic in IntrinsicsSPIRV.td
• [ ] In SPIRVInstructionSelector.cpp create the InstanceID lowering and map it to int_spv_InstanceID in SPIRVInstructionSelector::selectIntrinsic.
• [ ] Create SPIR-V backend test case in llvm/test/CodeGen/SPIRV/hlsl-intrinsics/InstanceID.ll

DirectX

DXIL Opcode	DXIL OpName	Shader Model	Shader Stages
141	InstanceID	6.3	('library', 'intersection', 'anyhit', 'closesthit')

SPIR-V

See https://registry.khronos.org/vulkan/specs/1.3-extensions/man/html/InstanceCustomIndexKHR.html

Test Case(s)

Example 1

//dxc InstanceID_test.hlsl -T lib_6_8 -enable-16bit-types -O0

export uint fn() {
    return InstanceID();
}

SPIRV Example(s):

Example 2

//dxc InstanceID_spirv_test.hlsl -T lib_6_8 -E fn -enable-16bit-types -spirv -fspv-target-env=universal1.5 -fcgl -O0

[shader("intersection")]
void fn() {
uint    ret = InstanceID();
}

HLSL:

The user-provided identifier for the instance on the bottom-level acceleration structure instance within the top-level structure.

Syntax

uint InstanceID();

Remarks

This function can be called from the following raytracing shader types:

• Any Hit Shader
• Closest Hit Shader
• Intersection Shader

See also

[Direct3D 12 Raytracing HLSL Reference](https://github.com/MicrosoftDocs/win32/blob/docs/desktop-src//direct3d12/direct3d-12-raytracing-hlsl-reference.md)

[farzonl]

@EugeneZelenko These bugs were created via automation. There are going to be about 160+ of these coming in. This first run was just a test. Would you like me to add the metabug label to all the issues created by the bot?

[EugeneZelenko]

@farzonl: metabug label should be used for issues that are used for tracking multiple issues, so bot could apply the label to such issues.