Implement the `asint` HLSL Function

[farzonl]

Note: see how we did asfloat and asuint.

• Link bitcast clang builtin for int with asint hlsl_intrinsics.h
• Add checks for asint
• Add codegen tests to clang/test/CodeGenHLSL/builtins/asint.hlsl
• Add sema tests to clang/test/SemaHLSL/BuiltIns/asint-errors.hlsl

DirectX

There were no DXIL opcodes found for asint.

SPIR-V

There were no SPIRV opcodes found for asint.

Test Case(s)

Example 1

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

export int4 fn(float p1) {
    return asint(p1);
}

Example 2

//dxc asint_1_test.hlsl -T lib_6_8 -enable-16bit-types -O0

export int4 fn(uint p1) {
    return asint(p1);
}

Example 3

//dxc asint_2_test.hlsl -T lib_6_8 -enable-16bit-types -O0

export int4 fn(int p1) {
    return asint(p1);
}

HLSL:

Interprets the bit pattern of x as an integer.

ret asint(x)

Parameters

Item	Description
x	[in] The input value.

Return Value

The input interpreted as an integer.

Type Description

Name	Template Type	Component Type	Size
x	scalar, vector, or matrix	float, uint	any
ret	same as input x	int	same dimension(s) as input x

Minimum Shader Model

This function is supported in the following shader models.

Shader Model	Supported
Shader Model 4 and higher shader models	yes
Shader Model 3 (DirectX HLSL)	no
Shader Model 2 (DirectX HLSL)	no
Shader Model 1 (DirectX HLSL)	no

See also

Intrinsic Functions (DirectX HLSL)

[inbelic]

I will start working on this