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pc64: assign fpsave/fprestore only once in fpuinit()

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This commit is contained in:
cinap_lenrek 2020-12-06 22:05:00 +01:00
parent cd38d41356
commit 23b52bbf23
1 changed files with 10 additions and 9 deletions
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19
sys/src/9/pc64/fpu.c
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@ -253,25 +253,26 @@ fpuinit(void)
ulong regs[4];
cr4 = getcr4() | CR4Osfxsr|CR4Oxmmex;
putcr4(cr4);
fpsave = fpssesave;
fprestore = fpsserestore;
if((m->cpuidcx & (Xsave|Avx)) == (Xsave|Avx) && getconf("*noavx") == nil){
cr4 |= CR4Oxsave;
putcr4(cr4);
m->xcr0 = 7; /* x87, sse, avx */
putxcr0(m->xcr0);
fpsave = fpxsave;
fprestore = fpxrestore;
cpuid(0xd, 1, regs);
if(regs[0] & Xsaveopt)
fpsave = fpxsaveopt;
if(regs[0] & Xsaves){
fpsave = fpxsaves;
fprestore = fpxrestores;
} else {
if(regs[0] & Xsaveopt)
fpsave = fpxsaveopt;
else
fpsave = fpxsave;
fprestore = fpxrestore;
}
} else {
putcr4(cr4);
fpsave = fpssesave;
fprestore = fpsserestore;
}
}