- extract valid instruction set extensions
#include <sys/auxv.h> uint_t getisax(uint32_t *array, uint_t n);
The getisax() function sets the vector array of n 32–bit integers to contain the bits from the AV_xxx_yyy namespace of the given instruction set architecture.
Values for AV_xxx_yyy for SPARC and SPARCV9, and their associated descriptions, can be found in <sys/auxv_SPARC.h>.
Values for AV_xxx_yyy for i386 and AMD64, and their associated descriptions, can be found in <sys/auxv_386.h>.
The getisax() function returns the number of array elements that contain non-zero values.
Example 1 Use getisax() to determine if the SSE2 instruction set is present.
In the following example, if the message is written, the SSE2 instruction set is present and fully supportred by the operating system.
uint_t ui; (void) getisax(&ui, 1); if (ui & AV_386_SSE2) printf("SSE2 instruction set extension is present.\n");
See attributes(5) for descriptions of the following attributes: