contrib/restricted/aws/aws-c-common/source/arch/intel/asm/cpuid.c


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/**
 * Copyright Amazon.com, Inc. or its affiliates. All Rights Reserved.
 * SPDX-License-Identifier: Apache-2.0.
 */

#include <aws/common/cpuid.h>

void aws_run_cpuid(uint32_t eax, uint32_t ecx, uint32_t *abcd) {
    uint32_t ebx = 0;
    uint32_t edx = 0;

#if defined(__i386__) && defined(__PIC__)
    /* in case of PIC under 32-bit EBX cannot be clobbered */
    __asm__ __volatile__("movl %%ebx, %%edi \n\t "
                         "cpuid \n\t "
                         "xchgl %%ebx, %%edi"
                         : "=D"(ebx),
#else
    __asm__ __volatile__("cpuid"
                         : "+b"(ebx),
#endif
                           "+a"(eax),
                           "+c"(ecx),
                           "=d"(edx));
    abcd[0] = eax;
    abcd[1] = ebx;
    abcd[2] = ecx;
    abcd[3] = edx;
}