Add XMM FPU registers save/restore support.

	* i386/include/mach/i386/fp_reg.h (struct i386_fp_regs): Invert array
	indices.
	(struct i386_xfp_save): New structure.
	(FP_387X): New macro.
	* i386/i386/thread.h (struct i386_fpsave_state): Add xfp_save_state
	member, keep existing fp_save_state and fp_regs members in an unnamed
	union member.  Move fp_valid member to the end of the structure.
	* i386/i386/fpu.h (fxsave, fxrstor): New macros.
	(fpu_save_context): Use fxsave() when FPU is FXSR-capable.
	* i386/i386/fpu.c: Include <i386/locore.h>
	(mxcsr_feature_mask): New variable.
	(fp_save, fp_load): Add declaration.
	(init_fpu): Add FXSR-capable FPU detection.
	(fpu_module_init): Request 16-byte alignment to zinit() for
	i386_fpsave_state structures.
	(twd_i387_to_fxsr, twd_fxsr_to_i387): New functions.
	(fpu_set_state): Convert FPU state when FPU is FXSR-capable.
	(fpu_get_state): Convert FPU state when FPU is FXSR-capable.
        (fpexterrflt): Pass to i386_exception either xfp_save_state or
        fp_save_state according to FPU type.
	(fpastintr): Likewise.
	(fp_load): Likewise.  Use fxrstor() when FPU is FXSR-capable.
	(fp_save): Use fxsave() when FPU is FXSR-capable.
	(fp_state_alloc): Add FXSR-aware initialization.

1 files changed, 10 insertions, 1 deletions

diff --git a/i386/i386/fpu.h b/i386/i386/fpu.h
index 7efb7e2..1a1b61f 100644
--- a/i386/i386/fpu.h
+++ b/i386/i386/fpu.h
@@ -67,6 +67,12 @@
 #define	frstor(state) \
 	asm volatile("frstor %0" : : "m" (state))
 
+#define	fxsave(state) \
+	asm volatile("fxsave %0" : "=m" (*state))
+
+#define	fxrstor(state) \
+	asm volatile("fxrstor %0" : : "m" (state))
+
 #define fwait() \
     	asm("fwait");
 
@@ -86,7 +92,10 @@
 	if (ifps != 0 && !ifps->fp_valid) { \
 	    /* registers are in FPU - save to memory */ \
 	    ifps->fp_valid = TRUE; \
-	    fnsave(&ifps->fp_save_state); \
+	    if (fp_kind == FP_387X) \
+		fxsave(&ifps->xfp_save_state); \
+	    else \
+		fnsave(&ifps->fp_save_state); \
 	    set_ts(); \
 	} \
     }