Implement the `isfinite` HLSL Function

[farzonl]

• Implement isfinite clang builtin,
• Link isfinite clang builtin with hlsl_intrinsics.h
• Add sema checks for isfinite to CheckHLSLBuiltinFunctionCall in SemaChecking.cpp
• Add codegen for isfinite to EmitHLSLBuiltinExpr in CGBuiltin.cpp
• Add codegen tests to clang/test/CodeGenHLSL/builtins/isfinite.hlsl
• Add sema tests to clang/test/SemaHLSL/BuiltIns/isfinite-errors.hlsl
• Create the int_dx_isfinite intrinsic in IntrinsicsDirectX.td
• Create the DXILOpMapping of int_dx_isfinite to 10 in DXIL.td
• Create the isfinite.ll and isfinite_errors.ll tests in llvm/test/CodeGen/DirectX/

DirectX

DXIL Opcode	DXIL OpName	Shader Model	Shader Stages
10	IsFinite	6.0	()

SPIR-V

There were no SPIR-V opcodes found for isfinite.

Test Case(s)

Example 1

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

export bool4 fn(float4 p1) {
    return isfinite(p1);
}

HLSL:

Determines if the specified floating-point value is finite.

ret isfinite(x)

Parameters

Item	Description
x	[in] The specified value.

Return Value

Returns a value of the same size as the input, with a value set to True if the x parameter is finite; otherwise False.

Type Description

Name	Template Type	Component Type	Size
x	scalar, vector, or matrix	float	any
ret	scalar, vector, or matrix	bool	as input

Minimum Shader Model

This function is supported in the following shader models.

Shader Model	Supported
Shader Model 2 (DirectX HLSL) and higher shader models	yes
Shader Model 1 (DirectX HLSL)	yes (vs_1_1 only)

Requirements

Requirement	Value
Header	Corecrt_math.h

See also

Intrinsic Functions (DirectX HLSL)