diff --git a/basis/cpu/ppc/bootstrap.factor b/basis/cpu/ppc/bootstrap.factor
index 7d5e359a80..9bf88185c5 100644
--- a/basis/cpu/ppc/bootstrap.factor
+++ b/basis/cpu/ppc/bootstrap.factor
@@ -11,8 +11,8 @@ big-endian on
 
 4 jit-code-format set
 
-: ds-reg 30 ;
-: rs-reg 31 ;
+: ds-reg 29 ;
+: rs-reg 30 ;
 
 : factor-area-size ( -- n ) 4 bootstrap-cells ;
 
diff --git a/basis/cpu/ppc/ppc.factor b/basis/cpu/ppc/ppc.factor
index 0857c4405c..77c4320f0c 100644
--- a/basis/cpu/ppc/ppc.factor
+++ b/basis/cpu/ppc/ppc.factor
@@ -19,10 +19,10 @@ namespaces compiler.codegen.fixup ;
 IN: cpu.ppc
 
 ! PowerPC register assignments:
-! r2-r28: integer vregs
-! r29: integer scratch
-! r30: data stack
-! r31: retain stack
+! r2-r27: integer vregs
+! r28: integer scratch
+! r29: data stack
+! r30: retain stack
 ! f0-f29: float vregs
 ! f30, f31: float scratch
 
@@ -40,13 +40,13 @@ IN: cpu.ppc
 
 M: ppc machine-registers
     {
-        { int-regs T{ range f 2 27 1 } }
+        { int-regs T{ range f 2 26 1 } }
         { double-float-regs T{ range f 0 28 1 } }
     } ;
 
-: scratch-reg 29 ; inline
-: fp-scratch-reg-1 30 ; inline
-: fp-scratch-reg-2 31 ; inline
+: scratch-reg 28 ; inline
+: fp-scratch-reg-1 29 ; inline
+: fp-scratch-reg-2 30 ; inline
 
 M: ppc two-operand? f ;
 
diff --git a/vm/cpu-ppc.S b/vm/cpu-ppc.S
index 9fadc5df4a..620bc9e991 100755
--- a/vm/cpu-ppc.S
+++ b/vm/cpu-ppc.S
@@ -60,8 +60,8 @@ DEF(void,c_to_factor,(CELL quot)):
 	PROLOGUE
 
 	SAVE_INT(r13,0)	   /* save GPRs */
-			   /* don't save ds pointer */
-			   /* don't save rs pointer */
+	SAVE_INT(r14,1)
+	SAVE_INT(r15,2)
 	SAVE_INT(r16,3)
 	SAVE_INT(r17,4)
 	SAVE_INT(r18,5)
@@ -75,9 +75,6 @@ DEF(void,c_to_factor,(CELL quot)):
 	SAVE_INT(r26,13)
 	SAVE_INT(r27,14)
 	SAVE_INT(r28,15)
-	SAVE_INT(r29,16)
-	SAVE_INT(r30,17)
-	SAVE_INT(r31,18)
 
 	SAVE_FP(f14,20)    /* save FPRs */
 	SAVE_FP(f15,22)
@@ -125,10 +122,7 @@ DEF(void,c_to_factor,(CELL quot)):
 	RESTORE_FP(f15,22)
 	RESTORE_FP(f14,20)    /* save FPRs */
 
-	RESTORE_INT(r31,18)    /* restore GPRs */
-	RESTORE_INT(r30,17)
-	RESTORE_INT(r29,16)
-	RESTORE_INT(r28,15)
+	RESTORE_INT(r28,15)   /* restore GPRs */
 	RESTORE_INT(r27,14)
 	RESTORE_INT(r26,13)
 	RESTORE_INT(r25,12)
@@ -141,8 +135,8 @@ DEF(void,c_to_factor,(CELL quot)):
 	RESTORE_INT(r18,5)
 	RESTORE_INT(r17,4)
 	RESTORE_INT(r16,3)
-			   /* don't restore rs pointer */
-			   /* don't restore ds pointer */
+	RESTORE_INT(r15,2)
+	RESTORE_INT(r14,1)
 	RESTORE_INT(r13,0)
 
 	EPILOGUE
diff --git a/vm/cpu-ppc.h b/vm/cpu-ppc.h
index 0f10aa34aa..298e21aa7d 100755
--- a/vm/cpu-ppc.h
+++ b/vm/cpu-ppc.h
@@ -1,8 +1,8 @@
 #define FACTOR_CPU_STRING "ppc"
 #define F_FASTCALL
 
-register CELL ds asm("r30");
-register CELL rs asm("r31");
+register CELL ds asm("r29");
+register CELL rs asm("r30");
 
 void c_to_factor(CELL quot);
 void undefined(CELL word);