mirrors/qemu
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity

Revert "host/i386: assume presence of SSE2"

Browse Source 
This reverts commit b18236897c.
The x86-64 instruction set can now be tuned down to x86-64 v1
or i386 Pentium Pro.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
This commit is contained in:
Paolo Bonzini 2024-06-18 17:34:48 +02:00
parent 39a367a42a
commit 87b8bde55d
3 changed files with 5 additions and 2 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

5
host/include/i386/host/bufferiszero.c.inc
View File

@ -110,13 +110,14 @@ static biz_accel_fn const accel_table[] = {
static unsigned best_accel(void)
{
#ifdef CONFIG_AVX2_OPT
unsigned info = cpuinfo_init();
#ifdef CONFIG_AVX2_OPT
if (info & CPUINFO_AVX2) {
return 2;
}
#endif
return 1;
return info & CPUINFO_SSE2 ? 1 : 0;
}
#else

1
host/include/i386/host/cpuinfo.h
View File

@ -14,6 +14,7 @@
#define CPUINFO_POPCNT (1u << 4)
#define CPUINFO_BMI1 (1u << 5)
#define CPUINFO_BMI2 (1u << 6)
#define CPUINFO_SSE2 (1u << 7)
#define CPUINFO_AVX1 (1u << 9)
#define CPUINFO_AVX2 (1u << 10)
#define CPUINFO_AVX512F (1u << 11)

1
util/cpuinfo-i386.c
View File

@ -34,6 +34,7 @@ unsigned __attribute__((constructor)) cpuinfo_init(void)
if (max >= 1) {
__cpuid(1, a, b, c, d);
info |= (d & bit_SSE2 ? CPUINFO_SSE2 : 0);
info |= (c & bit_MOVBE ? CPUINFO_MOVBE : 0);
info |= (c & bit_POPCNT ? CPUINFO_POPCNT : 0);
info |= (c & bit_PCLMUL ? CPUINFO_PCLMUL : 0);