Visible to Intel only — GUID: GUID-4A6AFD3E-C7E5-4666-8A0F-AE0661A4D726
Visible to Intel only — GUID: GUID-4A6AFD3E-C7E5-4666-8A0F-AE0661A4D726
Conditional Select Operators
For conditional select operands, the third and fourth operands determine the type returned. Third and fourth operands with same size, but different signedness, return the nearest common ancestor data type. For example:
- Return the nearest common ancestor data type if third and fourth operands are of the same size, but different signs:
I16vec4 R = select_neq(Is16vec4, Is16vec4, Is16vec4, Iu16vec4);
- Conditional select for equality:
R0 := (A0 == B0) ? C0 : D0; R1 := (A1 == B1) ? C1 : D1; R2 := (A2 == B2) ? C2 : D2; R3 := (A3 == B3) ? C3 : D3;
- Conditional select for inequality:
R0 := (A0 != B0) ? C0 : D0; R1 := (A1 != B1) ? C1 : D1; R2 := (A2 != B2) ? C2 : D2; R3 := (A3 != B3) ? C3 : D3;
Conditional Select Symbols and Corresponding Intrinsics
The following table lists the conditional select symbols and their corresponding intrinsics:
Conditional Select |
Operators |
Syntax |
Corresponding Intrinsic |
Additional Intrinsic (Applies to All) |
---|---|---|---|---|
Equality |
select_eq |
R = select_eq(A, B, C, D) |
_mm_cmpeq_pi32 |
_mm_and_si64
|
Inequality |
select_neq |
R = select_neq(A, B, C, D) |
_mm_cmpeq_pi32 |
|
Greater Than |
select_gt |
R = select_gt(A, B, C, D) |
_mm_cmpgt_pi32 |
|
Greater Than |
select_ge |
R = select_gt(A, B, C, D) |
_mm_cmpge_pi32 |
|
Less Than |
select_lt |
R = select_lt(A, B, C, D) |
_mm_cmplt_pi32 |
|
Less Than |
select_le |
R = select_le(A, B, C, D) |
_mm_cmple_pi32 |
Conditional Select Operator Overloading
All conditional select operands must be of the same size. The return data type is the nearest common ancestor of operands C and D. For conditional select operations using greater-than or less-than operations, the first and second operands must be signed as listed in the following table:
R |
Comparison |
A and B |
C |
D |
---|---|---|---|---|
I32vec2 R |
select_eq |
I[s|u]32vec2 |
I[s|u]32vec2 |
I[s|u]32vec2 |
I16vec4 R |
|
I[s|u]16vec4 |
I[s|u]16vec4 |
|
I8vec8 R |
|
I[s|u]8vec8 |
I[s|u]8vec8 |
|
I32vec2 R |
select_gt |
Is32vec2 |
Is32vec2 |
Is32vec2 |
I16vec4 R |
|
Is16vec4 |
Is16vec4 |
|
I8vec8 R |
|
Is8vec8 |
Is8vec8 |
Conditional Select Operator Return Value Mapping
The following table lists the mapping of return values from R0 to R7 for any number of elements. The same return value mappings also apply when there are fewer than four return values.
Return Value |
A Operands |
Available Operators | B Operands |
C and D Operands |
|||||
---|---|---|---|---|---|---|---|---|---|
R0:= |
A0 |
== |
!= |
> |
>= |
< |
<= |
B0 |
C0 : D0; |
R1:= |
A0 |
== |
!= |
> |
>= |
< |
<= |
B0 |
C1 : D1; |
R2:= |
A0 |
== |
!= |
> |
>= |
< |
<= |
B0 |
C2 : D2; |
R3:= |
A0 |
== |
!= |
> |
>= |
< |
<= |
B0 |
C3 : D3; |
R4:= |
A0 |
== |
!= |
> |
>= |
< |
<= |
B0 |
C4 : D4; |
R5:= |
A0 |
== |
!= |
> |
>= |
< |
<= |
B0 |
C5 : D5; |
R6:= |
A0 |
== |
!= |
> |
>= |
< |
<= |
B0 |
C6 : D6; |
R7:= |
A0 |
== |
!= |
> |
>= |
< |
<= |
B0 |
C7 : D7; |