Implement the `GetRemainingRecursionLevels` HLSL Function

[farzonl]

• Implement GetRemainingRecursionLevels clang builtin,
• Link GetRemainingRecursionLevels clang builtin with hlsl_intrinsics.h
• Add sema checks for GetRemainingRecursionLevels to CheckHLSLBuiltinFunctionCall in SemaChecking.cpp
• Add codegen for GetRemainingRecursionLevels to EmitHLSLBuiltinExpr in CGBuiltin.cpp
• Add codegen tests to clang/test/CodeGenHLSL/builtins/GetRemainingRecursionLevels.hlsl
• Add sema tests to clang/test/SemaHLSL/BuiltIns/GetRemainingRecursionLevels-errors.hlsl
• Create the int_dx_GetRemainingRecursionLevels intrinsic in IntrinsicsDirectX.td
• Create the DXILOpMapping of int_dx_GetRemainingRecursionLevels to 253 in DXIL.td
• Create the GetRemainingRecursionLevels.ll and GetRemainingRecursionLevels_errors.ll tests in llvm/test/CodeGen/DirectX/

DirectX

DXIL Opcode	DXIL OpName	Shader Model	Shader Stages
253	GetRemainingRecursionLevels	6.8	('node',)

SPIR-V

There is no support for GetRemainingRecursionLevels when targeting SPIR-V.

Test Case(s)

Example 1

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

RWBuffer<uint> buf0;

[shader("node")]
[NodeDispatchGrid(1, 1, 1)]
[numthreads(1, 1, 1)]
void fn() {

buf0[0] = GetRemainingRecursionLevels();
}

HLSL:

Syntax

uint GetRemainingRecursionLevels();

Type Description

Name	Template Type	Component Type	Size
ret	scalar	uint	1

Minimum Shader Model

This function is supported in the following shader models.

Shader Model	Supported
Shader Model 6.8 and higher shader models	yes

Shader Stages

• Node Shader

See also

• Intrinsic Functions (DirectX HLSL)
• See GetRemainingRecursionLevels