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scripts: improve the decodecode script

PATCH In review Arjan van de Ven 3 participants 5 messages Oct 29, 2008 – Oct 31, 2008

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#0 lore raw

PATCH 1/1 scripts: improve the decodecode script

Quoted 1 line

From 80bf813c2bdc3538d823bb59c2611b40673e395a Mon Sep 17 00:00:00 2001

From: Arjan van de Ven <[email protected]>
Date: Wed, 29 Oct 2008 09:57:07 -0700
Subject: [PATCH] scripts: improve the decodecode script

kerneloops.org has been using an improved "decodecode" script, specifically it has a special marker that shows which line in the assembly the oops happened at, like this:

  20:	83 e0 03             	and    $0x3,%eax
  23:	09 d8                	or     %ebx,%eax
  25:	85 db                	test   %ebx,%ebx
  27:	89 02                	mov    %eax,(%edx)
  29:	74 0f                	je     0x3a
  2b:*	3b 73 04             	cmp    0x4(%ebx),%esi     <-- trapping instruction
  2e:	75 05                	jne    0x35
  30:	89 53 04             	mov    %edx,0x4(%ebx)
  33:	eb 07                	jmp    0x3c
  35:	89 53 08             	mov    %edx,0x8(%ebx)

this patch updates the kernel copy to also have this functionality.

Signed-off-by Arjan van de Ven <[email protected]>
---
 scripts/decodecode |   32 ++++++++++++++++++++++----------
 1 files changed, 22 insertions(+), 10 deletions(-)
scripts/decodecode +22 -10
index 235d393..dd9bf17 100755
@@ -7,7 +7,7 @@
 # AFLAGS=--32 decodecode < 386.oops
 
 cleanup() {
-	rm -f $T $T.s $T.o
+	rm -f $T $T.s $T.o $T.oo $T.aa  $T.aaa
 	exit 1
 }
 

@@ -44,21 +44,33 @@ if [ $marker -eq 0 ]; then
 	marker=`expr index "$code" "\("`
 fi
 
+touch $T.oo
 if [ $marker -ne 0 ]; then
-	beforemark=`echo "$code" | cut -c-$((${marker} - 1))`
+	echo All code >> $T.oo
+	echo ======== >> $T.oo
+	beforemark=`echo "$code"`
 	echo -n "	.byte 0x" > $T.s
-	echo $beforemark | sed -e 's/ /,0x/g' >> $T.s
-	as $AFLAGS -o $T.o $T.s
-	objdump -S $T.o
-	rm $T.o $T.s
+	echo $beforemark | sed -e 's/ /,0x/g' | sed -e 's/<//g' | sed -e 's/>//g' >> $T.s
+	as $AFLAGS -o $T.o $T.s &> /dev/null
+	objdump -S $T.o | grep -v "/tmp" | grep -v "Disassembly" | grep -v "\.text" | grep -v "^$" &> $T.ooo
+	cat $T.ooo >> $T.oo
+	rm -f $T.o $T.s  $T.ooo
 
 # and fix code at-and-after marker
 	code=`echo "$code" | cut -c$((${marker} + 1))-`
 fi
-
+echo Code starting with the faulting instruction  > $T.aa
+echo =========================================== >> $T.aa
 code=`echo $code | sed -e 's/ [<(]/ /;s/[>)] / /;s/ /,0x/g'`
 echo -n "	.byte 0x" > $T.s
 echo $code >> $T.s
-as $AFLAGS -o $T.o $T.s
-objdump -S $T.o
-rm $T $T.s $T.o
+as $AFLAGS -o $T.o $T.s &> /dev/null
+objdump -S $T.o | grep -v "Disassembly" | grep -v "/tmp" | grep -v "\.text" | grep -v "^$" &> $T.aaa
+cat $T.aaa >> $T.aa
+
+faultline=`cat $T.aaa | head -1 | cut -d":" -f2`
+
+cat $T.oo | sed -e "s/\($faultline\)/\*\1     <-- trapping instruction/g"
+echo
+cat $T.aa
+rm -f $T.o $T.s $T $T.oo $T.aa  $T.aaa[5~
Signature · 8 lines
1.5.5.1



-- 
Arjan van de Ven 	Intel Open Source Technology Centre
For development, discussion and tips for power savings, 
visit http://www.lesswatts.org
#1 lore raw
Quoted 73 lines · Arjan van de Ven

From 80bf813c2bdc3538d823bb59c2611b40673e395a Mon Sep 17 00:00:00 2001
From: Arjan van de Ven <[email protected]>
Date: Wed, 29 Oct 2008 09:57:07 -0700
Subject: [PATCH] scripts: improve the decodecode script

kerneloops.org has been using an improved "decodecode" script, specifically it has a special marker that shows which line in the assembly the oops happened at, like this:

 20:	83 e0 03             	and    $0x3,%eax
 23:	09 d8                	or     %ebx,%eax
 25:	85 db                	test   %ebx,%ebx
 27:	89 02                	mov    %eax,(%edx)
 29:	74 0f                	je     0x3a
 2b:*	3b 73 04             	cmp    0x4(%ebx),%esi     <-- trapping instruction
 2e:	75 05                	jne    0x35
 30:	89 53 04             	mov    %edx,0x4(%ebx)
 33:	eb 07                	jmp    0x3c
 35:	89 53 08             	mov    %edx,0x8(%ebx)

this patch updates the kernel copy to also have this functionality.

Signed-off-by Arjan van de Ven <[email protected]>

---
scripts/decodecode | 32 ++++++++++++++++++++++----------

1 files changed, 22 insertions(+), 10 deletions(-)
scripts/decodecode +1 -1
index 235d393..dd9bf17 100755
@@ -7,7 +7,7 @@
 # AFLAGS=--32 decodecode < 386.oops
 
 cleanup() {
-	rm -f $T $T.s $T.o
+	rm -f $T $T.s $T.o $T.oo $T.aa  $T.aaa
 	exit 1
 }
 

@@ -44,21 +44,33 @@ if [ $marker -eq 0 ]; then
 	marker=`expr index "$code" "\("`

fi

+touch $T.oo
if [ $marker -ne 0 ]; then

scripts/decodecode +3 -1
-	beforemark=`echo "$code" | cut -c-$((${marker} - 1))`
+	echo All code >> $T.oo
+	echo ======== >> $T.oo
+	beforemark=`echo "$code"`

	echo -n "	.byte 0x" > $T.s
scripts/decodecode +5 -4
-	echo $beforemark | sed -e 's/ /,0x/g' >> $T.s
-	as $AFLAGS -o $T.o $T.s
-	objdump -S $T.o
-	rm $T.o $T.s
+	echo $beforemark | sed -e 's/ /,0x/g' | sed -e 's/<//g' | sed -e 's/>//g' >> $T.s
+	as $AFLAGS -o $T.o $T.s &> /dev/null
+	objdump -S $T.o | grep -v "/tmp" | grep -v "Disassembly" | grep -v "\.text" | grep -v "^$" &> $T.ooo
+	cat $T.ooo >> $T.oo
+	rm -f $T.o $T.s  $T.ooo

# and fix code at-and-after marker
	code=`echo "$code" | cut -c$((${marker} + 1))-`
fi
scripts/decodecode +2 -1
-
+echo Code starting with the faulting instruction  > $T.aa
+echo =========================================== >> $T.aa

code=echo $code | sed -e 's/ [<(]/ /;s/[>)] / /;s/ /,0x/g'
echo -n " .byte 0x" > $T.s
echo $code >> $T.s

scripts/decodecode +0 -3
-as $AFLAGS -o $T.o $T.s
-objdump -S $T.o
-rm $T $T.s $T.o

scripts/decodecode if [ $marker -eq 0 ]; then · line 76

Quoted 10 lines
scripts/decodecode +10 -0
+as $AFLAGS -o $T.o $T.s &> /dev/null
+objdump -S $T.o | grep -v "Disassembly" | grep -v "/tmp" | grep -v "\.text" | grep -v "^$" &> $T.aaa
+cat $T.aaa >> $T.aa
+
+faultline=`cat $T.aaa | head -1 | cut -d":" -f2`
+
+cat $T.oo | sed -e "s/\($faultline\)/\*\1     <-- trapping instruction/g"
+echo
+cat $T.aa
+rm -f $T.o $T.s $T $T.oo $T.aa  $T.aaa[5~

what is $T.aaa[5~ ? :-)

And why not call cleanup() here?

Signature · 1 line
"Sometimes the only way to stay sane is to go a little crazy."
author
#2 lore raw
Quoted 89 lines · On Wed, 29 Oct 2008 17:22:26 +0000 Américo Wang <[email protected]>…
Quoted 83 lines · Arjan van de Ven

From 80bf813c2bdc3538d823bb59c2611b40673e395a Mon Sep 17 00:00:00 2001 From: Arjan van de Ven <[email protected]>
Date: Wed, 29 Oct 2008 09:57:07 -0700
Subject: [PATCH] scripts: improve the decodecode script

kerneloops.org has been using an improved "decodecode" script, specifically it has a special marker that shows which line in the assembly the oops happened at, like this:

 20:	83 e0 03             	and    $0x3,%eax
 23:	09 d8                	or     %ebx,%eax
 25:	85 db                	test   %ebx,%ebx
 27:	89 02                	mov    %eax,(%edx)
 29:	74 0f                	je     0x3a

2b:* 3b 73 04 cmp 0x4(%ebx),%esi
<-- trapping instruction 2e: 75 05
jne 0x35 30: 89 53 04 mov
%edx,0x4(%ebx) 33: eb 07 jmp 0x3c
35: 89 53 08 mov %edx,0x8(%ebx)

this patch updates the kernel copy to also have this functionality.

Signed-off-by Arjan van de Ven <[email protected]>

---
scripts/decodecode | 32 ++++++++++++++++++++++----------

1 files changed, 22 insertions(+), 10 deletions(-)
scripts/decodecode +1 -1
index 235d393..dd9bf17 100755
@@ -7,7 +7,7 @@
 # AFLAGS=--32 decodecode < 386.oops
 
 cleanup() {
-	rm -f $T $T.s $T.o
+	rm -f $T $T.s $T.o $T.oo $T.aa  $T.aaa
 	exit 1
 }
 

@@ -44,21 +44,33 @@ if [ $marker -eq 0 ]; then
 	marker=`expr index "$code" "\("`

fi

+touch $T.oo
if [ $marker -ne 0 ]; then

scripts/decodecode +3 -1
-	beforemark=`echo "$code" | cut -c-$((${marker} - 1))`
+	echo All code >> $T.oo
+	echo ======== >> $T.oo
+	beforemark=`echo "$code"`

	echo -n "	.byte 0x" > $T.s
scripts/decodecode +1 -4
-	echo $beforemark | sed -e 's/ /,0x/g' >> $T.s
-	as $AFLAGS -o $T.o $T.s
-	objdump -S $T.o
-	rm $T.o $T.s
+	echo $beforemark | sed -e 's/ /,0x/g' | sed -e 's/<//g' |

sed -e 's/>//g' >> $T.s

scripts/decodecode +2 -0
+	as $AFLAGS -o $T.o $T.s &> /dev/null
+	objdump -S $T.o | grep -v "/tmp" | grep -v "Disassembly" |

grep -v "\.text" | grep -v "^$" &> $T.ooo

scripts/decodecode +2 -0
+	cat $T.ooo >> $T.oo
+	rm -f $T.o $T.s  $T.ooo

# and fix code at-and-after marker
	code=`echo "$code" | cut -c$((${marker} + 1))-`
fi
scripts/decodecode +2 -1
-
+echo Code starting with the faulting instruction  > $T.aa
+echo =========================================== >> $T.aa

code=echo $code | sed -e 's/ [<(]/ /;s/[>)] / /;s/ /,0x/g'
echo -n " .byte 0x" > $T.s
echo $code >> $T.s

scripts/decodecode +2 -3
-as $AFLAGS -o $T.o $T.s
-objdump -S $T.o
-rm $T $T.s $T.o
+as $AFLAGS -o $T.o $T.s &> /dev/null
+objdump -S $T.o | grep -v "Disassembly" | grep -v "/tmp" | grep -v

"\.text" | grep -v "^$" &> $T.aaa +cat $T.aaa >> $T.aa

scripts/decodecode +4 -0
+
+faultline=`cat $T.aaa | head -1 | cut -d":" -f2`
+
+cat $T.oo | sed -e "s/\($faultline\)/\*\1     <-- trapping

instruction/g" +echo

scripts/decodecode

Quoted 2 lines
scripts/decodecode +2 -0
+cat $T.aa
+rm -f $T.o $T.s $T $T.oo $T.aa  $T.aaa[5~

what is $T.aaa[5~ ? :-)

Quoted 1 line

And why not call cleanup() here?

good point

update below

Quoted 1 line

From 232b53efebc0bdba0be17dd0a695494faf3fdb60 Mon Sep 17 00:00:00 2001

From: Arjan van de Ven <[email protected]>
Date: Wed, 29 Oct 2008 09:57:07 -0700
Subject: [PATCH] scripts: improve the decodecode script

kerneloops.org has been using an improved "decodecode" script, specifically it has a special marker that shows which line in the assembly the oops happened at, like this:

  20:	83 e0 03             	and    $0x3,%eax
  23:	09 d8                	or     %ebx,%eax
  25:	85 db                	test   %ebx,%ebx
  27:	89 02                	mov    %eax,(%edx)
  29:	74 0f                	je     0x3a
  2b:*	3b 73 04             	cmp    0x4(%ebx),%esi     <-- trapping instruction
  2e:	75 05                	jne    0x35
  30:	89 53 04             	mov    %edx,0x4(%ebx)
  33:	eb 07                	jmp    0x3c
  35:	89 53 08             	mov    %edx,0x8(%ebx)

this patch updates the kernel copy to also have this functionality.

Signed-off-by Arjan van de Ven <[email protected]>
---
 scripts/decodecode |   32 ++++++++++++++++++++++----------
 1 files changed, 22 insertions(+), 10 deletions(-)
scripts/decodecode +22 -10
index 235d393..4b00647 100755
@@ -7,7 +7,7 @@
 # AFLAGS=--32 decodecode < 386.oops
 
 cleanup() {
-	rm -f $T $T.s $T.o
+	rm -f $T $T.s $T.o $T.oo $T.aa  $T.aaa
 	exit 1
 }
 

@@ -44,21 +44,33 @@ if [ $marker -eq 0 ]; then
 	marker=`expr index "$code" "\("`
 fi
 
+touch $T.oo
 if [ $marker -ne 0 ]; then
-	beforemark=`echo "$code" | cut -c-$((${marker} - 1))`
+	echo All code >> $T.oo
+	echo ======== >> $T.oo
+	beforemark=`echo "$code"`
 	echo -n "	.byte 0x" > $T.s
-	echo $beforemark | sed -e 's/ /,0x/g' >> $T.s
-	as $AFLAGS -o $T.o $T.s
-	objdump -S $T.o
-	rm $T.o $T.s
+	echo $beforemark | sed -e 's/ /,0x/g' | sed -e 's/<//g' | sed -e 's/>//g' >> $T.s
+	as $AFLAGS -o $T.o $T.s &> /dev/null
+	objdump -S $T.o | grep -v "/tmp" | grep -v "Disassembly" | grep -v "\.text" | grep -v "^$" &> $T.ooo
+	cat $T.ooo >> $T.oo
+	rm -f $T.o $T.s  $T.ooo
 
 # and fix code at-and-after marker
 	code=`echo "$code" | cut -c$((${marker} + 1))-`
 fi
-
+echo Code starting with the faulting instruction  > $T.aa
+echo =========================================== >> $T.aa
 code=`echo $code | sed -e 's/ [<(]/ /;s/[>)] / /;s/ /,0x/g'`
 echo -n "	.byte 0x" > $T.s
 echo $code >> $T.s
-as $AFLAGS -o $T.o $T.s
-objdump -S $T.o
-rm $T $T.s $T.o
+as $AFLAGS -o $T.o $T.s &> /dev/null
+objdump -S $T.o | grep -v "Disassembly" | grep -v "/tmp" | grep -v "\.text" | grep -v "^$" &> $T.aaa
+cat $T.aaa >> $T.aa
+
+faultline=`cat $T.aaa | head -1 | cut -d":" -f2`
+
+cat $T.oo | sed -e "s/\($faultline\)/\*\1     <-- trapping instruction/g"
+echo
+cat $T.aa
+cleanup
Signature · 7 lines
1.5.5.1


-- 
Arjan van de Ven 	Intel Open Source Technology Centre
For development, discussion and tips for power savings, 
visit http://www.lesswatts.org
Reviewed-by WANG Cong
#3 lore raw
Quoted 92 lines · Arjan van de Ven
Quoted 89 lines · On Wed, 29 Oct 2008 17:22:26 +0000 Américo Wang <[email protected]>…
Quoted 83 lines · Arjan van de Ven

From 80bf813c2bdc3538d823bb59c2611b40673e395a Mon Sep 17 00:00:00 2001 From: Arjan van de Ven <[email protected]>
Date: Wed, 29 Oct 2008 09:57:07 -0700
Subject: [PATCH] scripts: improve the decodecode script

kerneloops.org has been using an improved "decodecode" script, specifically it has a special marker that shows which line in the assembly the oops happened at, like this:

 20:	83 e0 03             	and    $0x3,%eax
 23:	09 d8                	or     %ebx,%eax
 25:	85 db                	test   %ebx,%ebx
 27:	89 02                	mov    %eax,(%edx)
 29:	74 0f                	je     0x3a

2b:* 3b 73 04 cmp 0x4(%ebx),%esi
<-- trapping instruction 2e: 75 05
jne 0x35 30: 89 53 04 mov
%edx,0x4(%ebx) 33: eb 07 jmp 0x3c
35: 89 53 08 mov %edx,0x8(%ebx)

this patch updates the kernel copy to also have this functionality.

Signed-off-by Arjan van de Ven <[email protected]>

---
scripts/decodecode | 32 ++++++++++++++++++++++----------

1 files changed, 22 insertions(+), 10 deletions(-)
scripts/decodecode +1 -1
index 235d393..dd9bf17 100755
@@ -7,7 +7,7 @@
 # AFLAGS=--32 decodecode < 386.oops
 
 cleanup() {
-	rm -f $T $T.s $T.o
+	rm -f $T $T.s $T.o $T.oo $T.aa  $T.aaa
 	exit 1
 }
 

@@ -44,21 +44,33 @@ if [ $marker -eq 0 ]; then
 	marker=`expr index "$code" "\("`

fi

+touch $T.oo
if [ $marker -ne 0 ]; then

scripts/decodecode +3 -1
-	beforemark=`echo "$code" | cut -c-$((${marker} - 1))`
+	echo All code >> $T.oo
+	echo ======== >> $T.oo
+	beforemark=`echo "$code"`

	echo -n "	.byte 0x" > $T.s
scripts/decodecode +1 -4
-	echo $beforemark | sed -e 's/ /,0x/g' >> $T.s
-	as $AFLAGS -o $T.o $T.s
-	objdump -S $T.o
-	rm $T.o $T.s
+	echo $beforemark | sed -e 's/ /,0x/g' | sed -e 's/<//g' |

sed -e 's/>//g' >> $T.s

scripts/decodecode +2 -0
+	as $AFLAGS -o $T.o $T.s &> /dev/null
+	objdump -S $T.o | grep -v "/tmp" | grep -v "Disassembly" |

grep -v "\.text" | grep -v "^$" &> $T.ooo

scripts/decodecode +2 -0
+	cat $T.ooo >> $T.oo
+	rm -f $T.o $T.s  $T.ooo

# and fix code at-and-after marker
	code=`echo "$code" | cut -c$((${marker} + 1))-`
fi
scripts/decodecode +2 -1
-
+echo Code starting with the faulting instruction  > $T.aa
+echo =========================================== >> $T.aa

code=echo $code | sed -e 's/ [<(]/ /;s/[>)] / /;s/ /,0x/g'
echo -n " .byte 0x" > $T.s
echo $code >> $T.s

scripts/decodecode +2 -3
-as $AFLAGS -o $T.o $T.s
-objdump -S $T.o
-rm $T $T.s $T.o
+as $AFLAGS -o $T.o $T.s &> /dev/null
+objdump -S $T.o | grep -v "Disassembly" | grep -v "/tmp" | grep -v

"\.text" | grep -v "^$" &> $T.aaa +cat $T.aaa >> $T.aa

scripts/decodecode +4 -0
+
+faultline=`cat $T.aaa | head -1 | cut -d":" -f2`
+
+cat $T.oo | sed -e "s/\($faultline\)/\*\1     <-- trapping

instruction/g" +echo

scripts/decodecode

Quoted 2 lines
scripts/decodecode +2 -0
+cat $T.aa
+rm -f $T.o $T.s $T $T.oo $T.aa  $T.aaa[5~

what is $T.aaa[5~ ? :-)

Quoted 6 lines
Quoted 1 line

And why not call cleanup() here?

good point

update below

Looks good, thanks!

If you need, add:

Reviewed-by WANG Cong <[email protected]>
Signature · 1 line
"Sometimes the only way to stay sane is to go a little crazy."
#4 lore raw
In reply to Arjan van de Ven
Quoted 74 lines · On Wed, 29 Oct 2008 10:00:45 -0700 Arjan van de Ven wrote:

From 80bf813c2bdc3538d823bb59c2611b40673e395a Mon Sep 17 00:00:00 2001
From: Arjan van de Ven <[email protected]>
Date: Wed, 29 Oct 2008 09:57:07 -0700
Subject: [PATCH] scripts: improve the decodecode script

kerneloops.org has been using an improved "decodecode" script, specifically it has a special marker that shows which line in the assembly the oops happened at, like this:

  20:	83 e0 03             	and    $0x3,%eax
  23:	09 d8                	or     %ebx,%eax
  25:	85 db                	test   %ebx,%ebx
  27:	89 02                	mov    %eax,(%edx)
  29:	74 0f                	je     0x3a
  2b:*	3b 73 04             	cmp    0x4(%ebx),%esi     <-- trapping instruction
  2e:	75 05                	jne    0x35
  30:	89 53 04             	mov    %edx,0x4(%ebx)
  33:	eb 07                	jmp    0x3c
  35:	89 53 08             	mov    %edx,0x8(%ebx)

this patch updates the kernel copy to also have this functionality.

Signed-off-by Arjan van de Ven <[email protected]>
---
 scripts/decodecode |   32 ++++++++++++++++++++++----------
 1 files changed, 22 insertions(+), 10 deletions(-)
scripts/decodecode +12 -10
index 235d393..dd9bf17 100755
@@ -7,7 +7,7 @@
 # AFLAGS=--32 decodecode < 386.oops
 
 cleanup() {
-	rm -f $T $T.s $T.o
+	rm -f $T $T.s $T.o $T.oo $T.aa  $T.aaa
 	exit 1
 }
 

@@ -44,21 +44,33 @@ if [ $marker -eq 0 ]; then
 	marker=`expr index "$code" "\("`
 fi
 
+touch $T.oo
 if [ $marker -ne 0 ]; then
-	beforemark=`echo "$code" | cut -c-$((${marker} - 1))`
+	echo All code >> $T.oo
+	echo ======== >> $T.oo
+	beforemark=`echo "$code"`
 	echo -n "	.byte 0x" > $T.s
-	echo $beforemark | sed -e 's/ /,0x/g' >> $T.s
-	as $AFLAGS -o $T.o $T.s
-	objdump -S $T.o
-	rm $T.o $T.s
+	echo $beforemark | sed -e 's/ /,0x/g' | sed -e 's/<//g' | sed -e 's/>//g' >> $T.s
+	as $AFLAGS -o $T.o $T.s &> /dev/null
+	objdump -S $T.o | grep -v "/tmp" | grep -v "Disassembly" | grep -v "\.text" | grep -v "^$" &> $T.ooo
+	cat $T.ooo >> $T.oo
+	rm -f $T.o $T.s  $T.ooo
 
 # and fix code at-and-after marker
 	code=`echo "$code" | cut -c$((${marker} + 1))-`
 fi
-
+echo Code starting with the faulting instruction  > $T.aa
+echo =========================================== >> $T.aa
 code=`echo $code | sed -e 's/ [<(]/ /;s/[>)] / /;s/ /,0x/g'`
 echo -n "	.byte 0x" > $T.s
 echo $code >> $T.s
-as $AFLAGS -o $T.o $T.s
-objdump -S $T.o
-rm $T $T.s $T.o

scripts/decodecode if [ $marker -eq 0 ]; then · line 76

Quoted 10 lines
scripts/decodecode +10 -0
+as $AFLAGS -o $T.o $T.s &> /dev/null
+objdump -S $T.o | grep -v "Disassembly" | grep -v "/tmp" | grep -v "\.text" | grep -v "^$" &> $T.aaa
+cat $T.aaa >> $T.aa
+
+faultline=`cat $T.aaa | head -1 | cut -d":" -f2`
+
+cat $T.oo | sed -e "s/\($faultline\)/\*\1     <-- trapping instruction/g"
+echo
+cat $T.aa
+rm -f $T.o $T.s $T $T.oo $T.aa  $T.aaa[5~

Looks good with the exception of Américo's comments.

Thanks.
---
~Randy