x20090325-1559

1 files changed, 76 insertions, 0 deletions

diff --git a/Linux/386/include/fpuctl.h b/Linux/386/include/fpuctl.h
new file mode 100644
index 00000000..8389f6ee
--- /dev/null
+++ b/Linux/386/include/fpuctl.h
@@ -0,0 +1,76 @@
+/*
+ * Linux 386 fpu support
+ * Mimic Plan9 floating point support
+ */
+
+static 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)
+	);
+}
+
+static 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; 
+}
+
+static 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;
+}
+
+static void
+setfsr(ulong fsr)
+{
+	__asm__("fclex\n\t");
+}
+
+/* FCR */
+#define	FPINEX	(1<<5)
+#define	FPUNFL	((1<<4)|(1<<1))
+#define	FPOVFL	(1<<3)
+#define	FPZDIV	(1<<2)
+#define	FPINVAL	(1<<0)
+#define	FPRNR	(0<<10)
+#define	FPRZ	(3<<10)
+#define	FPRPINF	(2<<10)
+#define	FPRNINF	(1<<10)
+#define	FPRMASK	(3<<10)
+#define	FPPEXT	(3<<8)
+#define	FPPSGL	(0<<8)
+#define	FPPDBL	(2<<8)
+#define	FPPMASK	(3<<8)
+/* FSR */
+#define	FPAINEX	FPINEX
+#define	FPAOVFL	FPOVFL
+#define	FPAUNFL	FPUNFL
+#define	FPAZDIV	FPZDIV
+#define	FPAINVAL	FPINVAL