urbackup_backend/external/aws-cpp-sdk/AwsChecksums/source/intel/cpuid.c
2021-07-07 18:47:38 +02:00

42 lines
1.3 KiB
C
Executable File

/*
* Copyright 2010-2017 Amazon.com, Inc. or its affiliates. All Rights Reserved.
*
* Licensed under the Apache License, Version 2.0 (the "License").
* You may not use this file except in compliance with the License.
* A copy of the License is located at
*
* http://aws.amazon.com/apache2.0
*
* or in the "license" file accompanying this file. This file is distributed
* on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either
* express or implied. See the License for the specific language governing
* permissions and limitations under the License.
*/
#include <aws/checksums/private/cpuid.h>
#include <stdint.h>
#if defined(__x86_64__) && !(defined(__GNUC__) && defined(DEBUG_BUILD))
static int32_t s_cpuid_output = 0;
static int s_cpuid_ran = 0;
int aws_checksums_do_cpu_id(int32_t *cpuid) {
if (!s_cpuid_ran) {
asm volatile("XOR %%rax, %%rax # zero the eax register\n"
"INC %%eax # eax=1 for processor feature bits\n"
"CPUID #get feature bits\n"
: "=c"(s_cpuid_output)
: // none
: "%rax", "%rbx", "%rdx", "cc");
s_cpuid_ran = 1;
}
*cpuid = s_cpuid_output;
return 1;
}
#endif /* defined(__x86_64__) && !(defined(__GNUC__) && defined(DEBUG_BUILD)) */