[src/trunk]: src/sys/arch/vax/vax Bugfixes for emulated instructions MOVTC an...

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

details:   https://anonhg.NetBSD.org/src/rev/7f4e4acf2c5f
branches:  trunk
changeset: 555829:7f4e4acf2c5f
user:      ragge <ragge%NetBSD.org@localhost>
date:      Sun Nov 30 10:02:21 2003 +0000

description:
Bugfixes for emulated instructions MOVTC and MOVTUC, from Bertram Barth:

> - condition-codes should be set from (unmodified) srclen vs. dstlen
>   instead from the modified (register-) values after completion.
>
> - for MOVTUC the V-bit should be set if the esc-char was found.
>
> - the arguments for comparison should be reversed.
>
> - count is unsigned word, but for condition-codes the comparison
>   should be done with signed words (ie. N = srclen LSS dstlen)

diffstat:

 sys/arch/vax/vax/emulate.S |  18 ++++++++++++------
 1 files changed, 12 insertions(+), 6 deletions(-)

diffs (50 lines):

diff -r b4c9989df883 -r 7f4e4acf2c5f sys/arch/vax/vax/emulate.S
--- a/sys/arch/vax/vax/emulate.S        Sun Nov 30 09:22:25 2003 +0000
+++ b/sys/arch/vax/vax/emulate.S        Sun Nov 30 10:02:21 2003 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: emulate.S,v 1.3 2003/08/07 16:30:18 agc Exp $ */
+/*     $NetBSD: emulate.S,v 1.4 2003/11/30 10:02:21 ragge Exp $ */
 /*
  * Copyright (c) 1986, 1987 The Regents of the University of California.
  * All rights reserved.
@@ -126,7 +126,7 @@
        movb    %r11,(%r5)+
        sobgtr  %r4,Lmovtc_2loop
 Lmovtc_out:
-       cmpl    %r4,%r0
+       cmpw    arg1,arg5
        savepsl
        clrl    %r2
        return
@@ -140,21 +140,27 @@
        argl(4,%r3)             # (4) table address == %r3
        argl(6,%r5)             # (6) destination address == %r5
        arguw(5,%r4)            # (5) destination length == %r4
-       jeql    Lmovtuc_out
+       jeql    Lmovtuc_out1
 Lmovtuc_loop:
        tstl    %r0
-       jeql    Lmovtuc_out
+       jeql    Lmovtuc_out1
        movzbl  (%r1),%r2
        movzbl  (%r3)[%r2],%r2
        cmpl    %r2,%r11
-       jeql    Lmovtuc_out
+       jeql    Lmovtuc_out2
        movzbl  (%r1)+,%r2
        movb    (%r3)[%r2],(%r5)+
        decl    %r0
        sobgtr  %r4,Lmovtuc_loop
+Lmovtuc_out1:
+       clrl    %r2             # clear V-bit
+       brb     Lmovtuc_out
+Lmovtuc_out2:
+       movl    $2,%r2          # set V-bit
 Lmovtuc_out:
-       cmpl    %r4,%r0
+       cmpw    arg1,arg5
        savepsl
+       bisl2   %r2,4(%sp)      # merge V-bit into psl
        clrl    %r2
        return