Intel® C++ Compiler Classic Developer Guide and Reference

ID 767249
Date 12/16/2022
Public

A newer version of this document is available. Customers should click here to go to the newest version.

Visible to Intel only — GUID: GUID-AD64EEC3-8913-4A84-B364-AC0D6C9FD47C

Document Table of Contents

Comparison Operators

The equality and inequality comparison operands can have mixed signedness, but they must be of the same size. The comparison operators for less-than and greater-than must be of the same sign and size.

Example of Syntax Usage for Comparison Operator

The nearest common ancestor is returned for compare for equal/not-equal operations.

Iu8vec8 A;

Is8vec8 B;

I8vec8 C;

C = cmpneq(A,B);

Type cast needed for different-sized elements for equal/not-equal comparisons.

Iu8vec8 A, C;

Is16vec4 B;

C = cmpeq(A,(Iu8vec8)B);

Type cast needed for sign or size differences for less-than and greater-than comparisons.

Iu16vec4 A;

Is16vec4 B, C;

C = cmpge((Is16vec4)A,B);

C = cmpgt(B,C);

Inequality Comparison Symbols and Corresponding Intrinsics

Compare For:

Operators

Syntax

Intrinsic

Equality

cmpeq

R = cmpeq(A, B)

_mm_cmpeq_pi32
_mm_cmpeq_pi16
_mm_cmpeq_pi8

Inequality

cmpneq

R = cmpneq(A, B)

_mm_cmpeq_pi32
_mm_cmpeq_pi16
_mm_cmpeq_pi8
_mm_andnot_si64

Greater Than

cmpgt

R = cmpgt(A, B)

_mm_cmpgt_pi32
_mm_cmpgt_pi16
_mm_cmpgt_pi8

Greater Than
or Equal To

cmpge

R = cmpge(A, B)

_mm_cmpgt_pi32
_mm_cmpgt_pi16
_mm_cmpgt_pi8
_mm_andnot_si64

Less Than

cmplt

R = cmplt(A, B)

_mm_cmpgt_pi32
_mm_cmpgt_pi16
_mm_cmpgt_pi8

Comparison operators have the restriction that the operands must be the size and sign as listed in the Compare Operator Overloading table.

Compare Operator Overloading

R

Comparison

A

B

I32vec2 R

cmpeq
cmpne

I[s|u]32vec2 B

I[s|u]32vec2 B

I16vec4 R

 

I[s|u]16vec4 B

I[s|u]16vec4 B

I8vec8 R

 

I[s|u]8vec8 B

I[s|u]8vec8 B

I32vec2 R

cmpgt
cmpge
cmplt
cmple

Is32vec2 B

Is32vec2 B

I16vec4 R

 

Is16vec4 B

Is16vec4 B