Intel® C++ Compiler Classic Developer Guide and Reference

ID 767249
Date 7/13/2023
Public
Document Table of Contents

Test Intrinsics

These Intel® Streaming SIMD Extensions (Intel® SSE4) intrinsics perform packed integer 128-bit comparisons. The prototypes for these intrinsics are in the smmintrin.h file.

To use these intrinsics, include the immintrin.h file as follows:

#include <immintrin.h>

Intrinsic Name

Operation

Corresponding
Intel® SSE4 Instruction

_mm_testz_si128

Checks for all zeros in specified bits of a 128-bit value

PTEST

_mm_testc_si128

Checks for all ones in specified bits of a 128-bit value

PTEST

_mm_testnzc_si128

Checks for at least one '0' and at least one '1' in the specified bits of a 128-bit value

PTEST

_mm_testz_si128

int _mm_testz_si128(__m128i s1, __m128i s2);

Returns '1' if the bitwise AND operation on s1 and s2 results in all zeros, else returns '0'. That is,

_mm_testz_si128 := ( (s1 & s2) == 0 ? 1 : 0 )

This intrinsic checks if the ZF flag equals '1' as a result of the instruction PTEST s1, s2. For example, it allows you to check if all set bits in s2 (mask) are zeros in s1.

Corresponding instruction: PTEST

_mm_testc_si128

int _mm_testc_si128(__m128i s1, __m128i s2);

Returns '1' if the bitwise AND operation on s2 and logical NOT s1 results in all zeros, else returns '0'. That is,

_mm_testc_si128 := ( (~s1 & s2) == 0 ? 1 : 0 )

This intrinsic checks if the CF flag equals '1' as a result of the instruction PTEST s1, s2. For example it allows you to check if all set bits in s2 (mask) are also set in s1.

Corresponding instruction: PTEST

_mm_testnzc_si128

int _mm_testnzc_si128(__m128i s1, __m128i s2);

Returns '1' if the following conditions are true: bitwise operation of s1 AND s2 does not equal all zeros and bitwise operation of NOT s1 AND s2 does not equal all zeros, otherwise returns '0'. That is,

_mm_testnzc_si128 := ( ( (s1 & s2) != 0 && (~s1 & s2) != 0 ) ? 1 : 0 )

This intrinsic checks if both the CF and ZF flags are not '1' as a result of the instruction PTEST s1, s2. For example, it allows you to check that the result has both zeros and ones in s1 on positions specified as set bits in s2 (mask).

Corresponding instruction: PTEST