[src/trunk]: src/sys/arch/i386 In setregs(), initialize the process's MXCSR t...

[thorpej <thorpej%NetBSD.org@localhost>]

details:   https://anonhg.NetBSD.org/src/rev/67b2f3c676a5
branches:  trunk
changeset: 513534:67b2f3c676a5
user:      thorpej <thorpej%NetBSD.org@localhost>
date:      Fri Aug 03 01:24:39 2001 +0000

description:
In setregs(), initialize the process's MXCSR to the reset-default
value as documented in the IA-32 Instruction Set Reference (in the
description of the LDMXCSR insn).

diffstat:

 sys/arch/i386/i386/machdep.c |  7 ++++---
 sys/arch/i386/include/npx.h  |  8 +++++++-
 2 files changed, 11 insertions(+), 4 deletions(-)

diffs (44 lines):

diff -r e63e7d21ffd3 -r 67b2f3c676a5 sys/arch/i386/i386/machdep.c
--- a/sys/arch/i386/i386/machdep.c      Fri Aug 03 01:21:34 2001 +0000
+++ b/sys/arch/i386/i386/machdep.c      Fri Aug 03 01:24:39 2001 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: machdep.c,v 1.451 2001/08/02 22:04:28 thorpej Exp $    */
+/*     $NetBSD: machdep.c,v 1.452 2001/08/03 01:24:40 thorpej Exp $    */
 
 /*-
  * Copyright (c) 1996, 1997, 1998, 2000 The NetBSD Foundation, Inc.
@@ -2166,9 +2166,10 @@
 
        p->p_md.md_flags &= ~MDP_USEDFPU;
        pcb->pcb_flags = 0;
-       if (i386_use_fxsave)
+       if (i386_use_fxsave) {
                pcb->pcb_savefpu.sv_xmm.sv_env.en_cw = __NetBSD_NPXCW__;
-       else
+               pcb->pcb_savefpu.sv_xmm.sv_env.en_mxcsr = __INITIAL_MXCSR__;
+       } else
                pcb->pcb_savefpu.sv_87.sv_env.en_cw = __NetBSD_NPXCW__;
 
        tf = p->p_md.md_regs;
diff -r e63e7d21ffd3 -r 67b2f3c676a5 sys/arch/i386/include/npx.h
--- a/sys/arch/i386/include/npx.h       Fri Aug 03 01:21:34 2001 +0000
+++ b/sys/arch/i386/include/npx.h       Fri Aug 03 01:24:39 2001 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: npx.h,v 1.16 2001/08/03 01:11:49 thorpej Exp $ */
+/*     $NetBSD: npx.h,v 1.17 2001/08/03 01:24:39 thorpej Exp $ */
 
 /*-
  * Copyright (c) 1990 The Regents of the University of California.
@@ -150,6 +150,12 @@
 #define        __SVR4_NPXCW__          0x0262
 
 /*
+ * The default MXCSR value at reset is 0x1f80, IA-32 Instruction
+ * Set Reference, pg. 3-369.
+ */
+#define        __INITIAL_MXCSR__       0x1f80
+
+/*
  * The standard control word from finit is 0x37F, giving:
  *     round to nearest
  *     64-bit precision