diff --git a/mach/vax4/libem/lpb.s b/mach/vax4/libem/lpb.s
index 4150bb4ab..8d92d6754 100644
--- a/mach/vax4/libem/lpb.s
+++ b/mach/vax4/libem/lpb.s
@@ -1,18 +1,25 @@
         # $Header$
+	# special version to work with A68S, by CHL
 .globl	.lpb
-
+        # compute AB, given LB
 .lpb:
 	cmpl	r0,fp
 	bneq	L1
 	moval	4(ap),r0
 	rsb
 L1:
-	movl	fp,r1
+        movl    4(r0),r1        # mask for saved registers
+        addl2   $24,r0          # position of AB if no registers saved
+        movl    $16,r2          # position of first bit to test
 L2:
-	cmpl	12(r1),r0
-	beql	L3
-	movl	12(r1),r1
-	jbr	L2
+        subl3   r2,$28,r3       # remaining size of mask
+        ffs     r2,r3,r1,r2     # find first bit set in mask
+        beql    L3              # no more bits set
+        addl2   $4,r0           # for each saved register
+        incl    r2
+        jbr     L2
 L3:
-	addl3	$4,8(r1),r0	# Argument Base = ap + 4
-	rsb
+        extzv   $30,$2,r1,r2    # Now find out about the stack alignment
+                                # between fp and ap
+        addl2   r2,r0           # add alignment
+        rsb
diff --git a/mach/vax4/libem/strlb.s b/mach/vax4/libem/strlb.s
index 463f8bbb3..23065e107 100644
--- a/mach/vax4/libem/strlb.s
+++ b/mach/vax4/libem/strlb.s
@@ -1,4 +1,5 @@
 	# $Header$
+	# revised version by CHL
 .globl .strlb
 	# Store the value that is on the stack in fp.
 	# Compute ap.
@@ -9,16 +10,16 @@
 	movl	$20,ap		# Compute argumentbase from local base.
 				# Distance is 5 longwords + the number of
 				# registers saved.
-	movl	$1,r3		# Now check register save mask
-	movl	$12,r2
-L1:
-	bitl	r3,6(fp)
-	beql	L2
-	addl2	$4,ap		# Add 1 longword for each register saved
-L2:
-	ashl	$1,r3,r3
-	sobgeq	r2,L1
-
+	movl	4(fp),r3	# mask for saved registers
+	movl	$16,r2		# position of first bit to test
+L4:
+        subl3   r2,$28,r1       # remaining size of mask
+        ffs     r2,r1,r3,r2     # find first bit set in mask
+        beql    L5              # no more bits set
+        addl2   $4,ap           # for each saved register
+        incl    r2
+        jbr     L4
+L5:
 	extzv	$14,$2,6(fp),r3	# Now find out about the stack alignment
 				# between fp and ap
 	addl2	r3,ap		# add alignment