usubb (sm5 - asm)

Unsigned integer subtract with borrow.

usubb dst0[.mask], dst1[.mask], src0[.swizzle], src1[.swizzle]

Item	Description
dst0	[in] Contains the LSAB results of the instruction.
dst1	[in] The corresponding component of dst0 that specifies if a borrow was produced.
src0	[in] The value from which to subtract.
src1	[in] The amount to subtract from src0.

Remarks

This instruction performs a component-wise unsigned subtract of 32-bit operands src1 from src0, placing the LSB part of the 32-bit result in dst0.

The corresponding component in dst1 is written with 1 if a borrow is produced, 0 otherwise.

dst1 can be NULL if the borrow is not needed.

This instruction applies to the following shader stages:

Vertex	Hull	Domain	Geometry	Pixel	Compute
X	X	X	X	X	X

Minimum Shader Model

This instruction is supported in the following shader models:

Shader Model	Supported
Shader Model 5	yes
Shader Model 4.1	no
Shader Model 4	no
Shader Model 3 (DirectX HLSL)	no
Shader Model 2 (DirectX HLSL)	no
Shader Model 1 (DirectX HLSL)	no

Related topics

Shader Model 5 Assembly (DirectX HLSL)