callnz pred (Pixel Shader) 
Call if not zero, with a predicate. Performs a conditional call to the instruction marked by the label index. Predication uses a boolean value to determine whether of not to perform the instruction.
Syntax
| callnz label, [!] p0.replicateSwizzle | 
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where:
- label specifies a label number.
 - [!] is an optional boolean NOT.
 - p0 is the predicate register. See Predicate. 
 - replicateSwizzle specifies the component that contains the predicate value. Valid components are: x, y, z, w or r, g, b, a. The predicate value can be modified with the negate modifier. 
 
Remarks
| Pixel shader versions | 1_1 | 1_2 | 1_3 | 1_4 | 2_0 | 2_x | 2_sw | 3_0 | 3_sw | 
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| callnz pred |  |  |  |  |  | x | x | x | x | 
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This instruction does the following:
if (specified register component is not zero)
{
    Push address of the next instruction to the return address stack.
    Continue execution from the instruction marked by the label.
}
| Minimum operating system | Windows 98 | 
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