From 37e9221a5d1905cba45c96ac44dbe26d947bc4af Mon Sep 17 00:00:00 2001 From: charles forsyth Date: Sun, 18 May 2014 14:19:01 +0100 Subject: 20140518-1419 --- lib9/setfcr-OpenBSD-386.c | 57 +++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 57 insertions(+) create mode 100644 lib9/setfcr-OpenBSD-386.c (limited to 'lib9/setfcr-OpenBSD-386.c') diff --git a/lib9/setfcr-OpenBSD-386.c b/lib9/setfcr-OpenBSD-386.c new file mode 100644 index 00000000..c512f033 --- /dev/null +++ b/lib9/setfcr-OpenBSD-386.c @@ -0,0 +1,57 @@ +/* + * 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"); +} -- cgit v1.2.3