diff --git a/src/runtime/memclr_ppc64x.s b/src/runtime/memclr_ppc64x.s
index 3b23ce89d8..072963f756 100644
--- a/src/runtime/memclr_ppc64x.s
+++ b/src/runtime/memclr_ppc64x.s
@@ -14,34 +14,68 @@ TEXT runtime·memclrNoHeapPointers(SB), NOSPLIT|NOFRAME, $0-16
 	// Determine if there are doublewords to clear
 check:
 	ANDCC $7, R4, R5  // R5: leftover bytes to clear
-	SRAD  $3, R4, R6  // R6: double words to clear
+	SRD   $3, R4, R6  // R6: double words to clear
 	CMP   R6, $0, CR1 // CR1[EQ] set if no double words
 
-	BC     12, 6, nozerolarge // only single bytes
-	MOVD   R6, CTR            // R6 = number of double words
-	SRADCC $2, R6, R7         // 32 byte chunks?
-	BNE    zero32setup
+	BC    12, 6, nozerolarge // only single bytes
+	CMP   R4, $512
+	BLT   under512           // special case for < 512
+	ANDCC $127, R3, R8       // check for 128 alignment of address
+	BEQ   zero512setup
+
+	ANDCC $7, R3, R15
+	BEQ   zero512xsetup // at least 8 byte aligned
+
+	// zero bytes up to 8 byte alignment
+
+	ANDCC $1, R3, R15 // check for byte alignment
+	BEQ   byte2
+	MOVB  R0, 0(R3)   // zero 1 byte
+	ADD   $1, R3      // bump ptr by 1
+	ADD   $-1, R4
+
+byte2:
+	ANDCC $2, R3, R15 // check for 2 byte alignment
+	BEQ   byte4
+	MOVH  R0, 0(R3)   // zero 2 bytes
+	ADD   $2, R3      // bump ptr by 2
+	ADD   $-2, R4
+
+byte4:
+	ANDCC $4, R3, R15   // check for 4 byte alignment
+	BEQ   zero512xsetup
+	MOVW  R0, 0(R3)     // zero 4 bytes
+	ADD   $4, R3        // bump ptr by 4
+	ADD   $-4, R4
+	BR    zero512xsetup // ptr should now be 8 byte aligned
+
+under512:
+	MOVD  R6, CTR     // R6 = number of double words
+	SRDCC $2, R6, R7  // 32 byte chunks?
+	BNE   zero32setup
 
 	// Clear double words
 
 zero8:
 	MOVD R0, 0(R3)    // double word
 	ADD  $8, R3
+	ADD  $-8, R4
 	BC   16, 0, zero8 // dec ctr, br zero8 if ctr not 0
-	BR   nozerolarge  // handle remainder
+	BR   nozerolarge  // handle leftovers
 
 	// Prepare to clear 32 bytes at a time.
 
 zero32setup:
-	DCBTST (R3)    // prepare data cache
-	MOVD   R7, CTR // number of 32 byte chunks
+	DCBTST (R3)             // prepare data cache
+	XXLXOR VS32, VS32, VS32 // clear VS32 (V0)
+	MOVD   R7, CTR          // number of 32 byte chunks
+	MOVD   $16, R8
 
 zero32:
-	MOVD    R0, 0(R3)       // clear 4 double words
-	MOVD    R0, 8(R3)
-	MOVD    R0, 16(R3)
-	MOVD    R0, 24(R3)
+	STXVD2X VS32, (R3+R0)   // store 16 bytes
+	STXVD2X VS32, (R3+R8)
 	ADD     $32, R3
+	ADD     $-32, R4
 	BC      16, 0, zero32   // dec ctr, br zero32 if ctr not 0
 	RLDCLCC $61, R4, $3, R6 // remaining doublewords
 	BEQ     nozerolarge
@@ -49,8 +83,8 @@ zero32:
 	BR      zero8
 
 nozerolarge:
-	CMP R5, $0   // any remaining bytes
-	BC  4, 1, LR // ble lr
+	ANDCC $7, R4, R5 // any remaining bytes
+	BC    4, 1, LR   // ble lr
 
 zerotail:
 	MOVD R5, CTR // set up to clear tail bytes
@@ -60,3 +94,70 @@ zerotailloop:
 	ADD  $1, R3
 	BC   16, 0, zerotailloop // dec ctr, br zerotailloop if ctr not 0
 	RET
+
+zero512xsetup:  // 512 chunk with extra needed
+	ANDCC $8, R3, R11    // 8 byte alignment?
+	BEQ   zero512setup16
+	MOVD  R0, 0(R3)      // clear 8 bytes
+	ADD   $8, R3         // update ptr to next 8
+	ADD   $-8, R4        // dec count by 8
+
+zero512setup16:
+	ANDCC $127, R3, R14 // < 128 byte alignment
+	BEQ   zero512setup  // handle 128 byte alignment
+	MOVD  $128, R15
+	SUB   R14, R15, R14 // find increment to 128 alignment
+	SRD   $4, R14, R15  // number of 16 byte chunks
+
+zero512presetup:
+	MOVD   R15, CTR         // loop counter of 16 bytes
+	XXLXOR VS32, VS32, VS32 // clear VS32 (V0)
+
+zero512preloop:  // clear up to 128 alignment
+	STXVD2X VS32, (R3+R0)         // clear 16 bytes
+	ADD     $16, R3               // update ptr
+	ADD     $-16, R4              // dec count
+	BC      16, 0, zero512preloop
+
+zero512setup:  // setup for dcbz loop
+	CMP  R4, $512   // check if at least 512
+	BLT  remain
+	SRD  $9, R4, R8 // loop count for 512 chunks
+	MOVD R8, CTR    // set up counter
+	MOVD $128, R9   // index regs for 128 bytes
+	MOVD $256, R10
+	MOVD $384, R11
+
+zero512:
+	DCBZ (R3+R0)        // clear first chunk
+	DCBZ (R3+R9)        // clear second chunk
+	DCBZ (R3+R10)       // clear third chunk
+	DCBZ (R3+R11)       // clear fourth chunk
+	ADD  $512, R3
+	ADD  $-512, R4
+	BC   16, 0, zero512
+
+remain:
+	CMP  R4, $128  // check if 128 byte chunks left
+	BLT  smaller
+	DCBZ (R3+R0)   // clear 128
+	ADD  $128, R3
+	ADD  $-128, R4
+	BR   remain
+
+smaller:
+	ANDCC $127, R4, R7 // find leftovers
+	BEQ   done
+	CMP   R7, $64      // more than 64, do 32 at a time
+	BLT   zero8setup   // less than 64, do 8 at a time
+	SRD   $5, R7, R7   // set up counter for 32
+	BR    zero32setup
+
+zero8setup:
+	SRDCC $3, R7, R7  // less than 8 bytes
+	BEQ   nozerolarge
+	MOVD  R7, CTR
+	BR    zero8
+
+done:
+	RET
diff --git a/src/runtime/memmove_ppc64x.s b/src/runtime/memmove_ppc64x.s
index b79f76d388..60cbcc41ec 100644
--- a/src/runtime/memmove_ppc64x.s
+++ b/src/runtime/memmove_ppc64x.s
@@ -16,7 +16,7 @@ TEXT runtime·memmove(SB), NOSPLIT|NOFRAME, $0-24
 	// copy so a more efficient move can be done
 check:
 	ANDCC	$7, R5, R7	// R7: bytes to copy
-	SRAD	$3, R5, R6	// R6: double words to copy
+	SRD	$3, R5, R6	// R6: double words to copy
 	CMP	R6, $0, CR1	// CR1[EQ] set if no double words to copy
 
 	// Determine overlap by subtracting dest - src and comparing against the
@@ -31,9 +31,9 @@ check:
 	// Copying forward if no overlap.
 
 	BC	12, 6, noforwardlarge	// "BEQ CR1, noforwardlarge"
-	MOVD	R6,CTR			// R6 = number of double words
-	SRADCC	$2,R6,R8		// 32 byte chunks?
+	SRDCC	$2,R6,R8		// 32 byte chunks?
 	BNE	forward32setup		//
+	MOVD	R6,CTR			// R6 = number of double words
 
 	// Move double words
 
@@ -51,17 +51,14 @@ forward32setup:
 	DCBTST	(R3)			// prepare data cache
 	DCBT	(R4)
 	MOVD	R8, CTR			// double work count
+	MOVD	$16, R8
 
 forward32:
-	MOVD	0(R4), R8		// load 4 double words
-	MOVD	8(R4), R9
-	MOVD	16(R4), R14
-	MOVD	24(R4), R15
-	ADD	$32,R4
-	MOVD	R8, 0(R3)		// store those 4
-	MOVD	R9, 8(R3)
-	MOVD	R14,16(R3)
-	MOVD	R15,24(R3)
+	LXVD2X	(R4+R0), VS32		// load 16 bytes
+	LXVD2X	(R4+R8), VS33
+	ADD	$32, R4
+	STXVD2X	VS32, (R3+R0)		// store 16 bytes
+	STXVD2X	VS33, (R3+R8)
 	ADD	$32,R3			// bump up for next set
 	BC	16, 0, forward32	// continue
 	RLDCLCC	$61,R5,$3,R6		// remaining doublewords
@@ -71,7 +68,7 @@ forward32:
 
 noforwardlarge:
 	CMP	R7,$0			// any remaining bytes
-	BC	4, 1, LR
+	BC	4, 1, LR		// ble lr
 
 forwardtail:
 	MOVD	R7, CTR			// move tail bytes
@@ -101,19 +98,39 @@ backwardtailloop:
 	SUB	$1,R4
 	MOVBZ 	R8, -1(R3)
 	SUB	$1,R3
-	BC	16, 0, backwardtailloop
+	BC	16, 0, backwardtailloop // bndz
 
 nobackwardtail:
-	CMP	R6,$0
-	BC	4, 5, LR
+	BC	4, 5, LR		// ble CR1 lr
 
 backwardlarge:
 	MOVD	R6, CTR
+	SUB	R3, R4, R9		// Use vsx if moving
+	CMP	R9, $32			// at least 32 byte chunks
+	BLT	backwardlargeloop	// and distance >= 32
+	SRDCC	$2,R6,R8		// 32 byte chunks
+	BNE	backward32setup
 
 backwardlargeloop:
 	MOVD 	-8(R4), R8
 	SUB	$8,R4
 	MOVD 	R8, -8(R3)
 	SUB	$8,R3
-	BC	16, 0, backwardlargeloop	//
+	BC	16, 0, backwardlargeloop // bndz
 	RET
+
+backward32setup:
+	MOVD	R8, CTR			// set up loop ctr
+	MOVD	$16, R8			// 32 bytes at at time
+
+backward32loop:
+	SUB	$32, R4
+	SUB	$32, R3
+	LXVD2X	(R4+R0), VS32           // load 16 bytes
+	LXVD2X	(R4+R8), VS33
+	STXVD2X	VS32, (R3+R0)           // store 16 bytes
+	STXVD2X	VS33, (R3+R8)
+	BC      16, 0, backward32loop   // bndz
+	BC	4, 5, LR		// ble CR1 lr
+	MOVD	R6, CTR
+	BR	backwardlargeloop