Index: hal/powerpc/arch/current/src/vectors.S
===================================================================
--- hal/powerpc/arch/current/src/vectors.S	(revision 3391)
+++ hal/powerpc/arch/current/src/vectors.S	(working copy)
@@ -368,11 +368,13 @@
         li      r0,0            # r0 = 0
         cmplw   r3,r4           # skip if no bss
         beq     2f
+        sub     r4,r4,r3        # compute number of words to clear
+        srwi    r4,r4,2
+        mtctr   r4
+        subi    r3,r3,4
         
-1:      stw     r0,0(r3)        # store zero
-        addi    r3,r3,4         # increment by 1 word
-        cmplw   r3,r4           # compare
-        blt     1b              # loop if not yet done
+1:      stwu    r0,4(r3)        # store zero & increment pointer
+        bdnz    1b
 2:
 
         # clear SBSS
@@ -380,11 +382,13 @@
         lwi     r4,__sbss_end   # r4 = end
         cmplw   r3,r4           # skip if no sbss
         beq     2f
+        sub     r4,r4,r3        # compute number of words to clear
+        srwi    r4,r4,2
+        mtctr   r4
+        subi    r3,r3,4
         
-1:      stw     r0,0(r3)        # store zero
-        addi    r3,r3,4         # increment by 1 word
-        cmplw   r3,r4           # compare
-        blt     1b              # loop if not yet done
+1:      stwu    r0,4(r3)        # store zero & increment pointer
+        bdnz    1b
 2:
 
         # It is now safe to call C functions which may rely on initialized