ref: c8b187f9db503465460d8bafa2d7a758bbcf59ca
dir: /lib9/setfcr-MacOSX-386.c/
/* * Linux 386 fpu support * Mimic Plan9 floating point support */ #include "lib9.h" void setfcr(ulong fcr) { __asm__( "xorb $0x3f, %%al\n\t" "pushw %%ax\n\t" "fwait\n\t" "fldcw (%%esp)\n\t" "popw %%ax\n\t" : /* no output */ : "al" (fcr) ); } ulong getfcr(void) { ulong fcr = 0; __asm__( "pushl %%eax\n\t" "fwait\n\t" "fstcw (%%esp)\n\t" "popl %%eax\n\t" "xorb $0x3f, %%al\n\t" : "=a" (fcr) : "eax" (fcr) ); return fcr; } ulong getfsr(void) { ulong fsr = -1; __asm__( "fwait\n\t" "fstsw (%%eax)\n\t" "movl (%%eax), %%eax\n\t" "andl $0xffff, %%eax\n\t" : "=a" (fsr) : "eax" (&fsr) ); return fsr; } void setfsr(ulong fsr) { __asm__("fclex\n\t"); }