+/// GetX86CpuIDAndInfoEx - Execute the specified cpuid with subleaf and return the
+/// 4 values in the specified arguments. If we can't run cpuid on the host,
+/// return true.
+static bool GetX86CpuIDAndInfoEx(unsigned value, unsigned subleaf,
+ unsigned *rEAX, unsigned *rEBX, unsigned *rECX,
+ unsigned *rEDX) {
+#if defined(__x86_64__) || defined(_M_AMD64) || defined (_M_X64)
+ #if defined(__GNUC__)
+ // gcc doesn't know cpuid would clobber ebx/rbx. Preseve it manually.
+ asm ("movq\t%%rbx, %%rsi\n\t"
+ "cpuid\n\t"
+ "xchgq\t%%rbx, %%rsi\n\t"
+ : "=a" (*rEAX),
+ "=S" (*rEBX),
+ "=c" (*rECX),
+ "=d" (*rEDX)
+ : "a" (value),
+ "c" (subleaf));
+ return false;
+ #elif defined(_MSC_VER)
+ // __cpuidex was added in MSVC++ 9.0 SP1
+ #if (_MSC_VER > 1500) || (_MSC_VER == 1500 && _MSC_FULL_VER >= 150030729)
+ int registers[4];
+ __cpuidex(registers, value, subleaf);
+ *rEAX = registers[0];
+ *rEBX = registers[1];
+ *rECX = registers[2];
+ *rEDX = registers[3];
+ return false;
+ #else
+ return true;
+ #endif
+ #else
+ return true;
+ #endif
+#elif defined(i386) || defined(__i386__) || defined(__x86__) || defined(_M_IX86)
+ #if defined(__GNUC__)
+ asm ("movl\t%%ebx, %%esi\n\t"
+ "cpuid\n\t"
+ "xchgl\t%%ebx, %%esi\n\t"
+ : "=a" (*rEAX),
+ "=S" (*rEBX),
+ "=c" (*rECX),
+ "=d" (*rEDX)
+ : "a" (value),
+ "c" (subleaf));
+ return false;
+ #elif defined(_MSC_VER)
+ __asm {
+ mov eax,value
+ mov ecx,subleaf
+ cpuid
+ mov esi,rEAX
+ mov dword ptr [esi],eax
+ mov esi,rEBX
+ mov dword ptr [esi],ebx
+ mov esi,rECX
+ mov dword ptr [esi],ecx
+ mov esi,rEDX
+ mov dword ptr [esi],edx
+ }
+ return false;
+ #else
+ return true;
+ #endif
+#else
+ return true;
+#endif
+}
+