diff --git a/ChangeLog b/ChangeLog
index 1a891e48a4896cb7fca001031b4d147df13692bf..d9166612c0ffb01d92b032eba8017312dd7fe5c5 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,9 @@
+2024-01-28  Niels Möller  <nisse@lysator.liu.se>
+
+	* powerpc64/p8/aes-encrypt-internal.asm: Use r10-r12 consistently
+	for indexing, and reducing number of used callee-save registers.
+	* powerpc64/p8/aes-decrypt-internal.asm: Likewise.
+
 2024-01-26  Niels Möller  <nisse@lysator.liu.se>
 
 	Delete all sparc32 assembly.
diff --git a/powerpc64/p8/aes-decrypt-internal.asm b/powerpc64/p8/aes-decrypt-internal.asm
index 1c33f2799feb18d95b6df86bfb7be5e4336a5223..6336e5b78c01265e0b925100c5bee65f6a981678 100644
--- a/powerpc64/p8/aes-decrypt-internal.asm
+++ b/powerpc64/p8/aes-decrypt-internal.asm
@@ -39,6 +39,7 @@ define(`KEYS', `r4')
 define(`LENGTH', `r6')
 define(`DST', `r7')
 define(`SRC', `r8')
+C r9 used as loop index register, r10-r12, r14-r17 as constants.
 
 define(`SWAP_MASK', `v0')
 
@@ -76,25 +77,24 @@ PROLOGUE(_nettle_aes_decrypt)
  subi ROUNDS,ROUNDS,1
  srdi LENGTH,LENGTH,4
 
+ C Used as offsets for load/store, throughout this function
+ li             r10,0x10
+ li             r11,0x20
+ li             r12,0x30
+
  srdi r5,LENGTH,3 #8x loop count
  cmpldi r5,0
  beq L4x
 
- std r25,-56(SP)
- std r26,-48(SP)
- std r27,-40(SP)
- std r28,-32(SP)
- std r29,-24(SP)
- std r30,-16(SP)
- std r31,-8(SP)
-
- li r25,0x10
- li r26,0x20
- li r27,0x30
- li r28,0x40
- li r29,0x50
- li r30,0x60
- li r31,0x70
+ std r14,-32(SP)
+ std r15,-24(SP)
+ std r16,-16(SP)
+ std r17,-8(SP)
+
+ li r14,0x40
+ li r15,0x50
+ li r16,0x60
+ li r17,0x70
 
 .align 5
 Lx8_loop:
@@ -102,56 +102,55 @@ Lx8_loop:
  vperm   K,K,K,SWAP_MASK
 
  lxvd2x VSR(S0),0,SRC
- lxvd2x VSR(S1),r25,SRC
- lxvd2x VSR(S2),r26,SRC
- lxvd2x VSR(S3),r27,SRC
- lxvd2x VSR(S4),r28,SRC
- lxvd2x VSR(S5),r29,SRC
- lxvd2x VSR(S6),r30,SRC
- lxvd2x VSR(S7),r31,SRC
+ lxvd2x VSR(S1),r10,SRC
+ lxvd2x VSR(S2),r11,SRC
+ lxvd2x VSR(S3),r12,SRC
+ lxvd2x VSR(S4),r14,SRC
+ lxvd2x VSR(S5),r15,SRC
+ lxvd2x VSR(S6),r16,SRC
+ lxvd2x VSR(S7),r17,SRC
 
 IF_LE(`OPN_XXXY(vperm, SWAP_MASK, S0,S1,S2,S3,S4,S5,S6,S7)')
 
  OPN_XXY(vxor, K, S0, S1, S2, S3, S4, S5, S6, S7)
 
  mtctr ROUNDS
- li r10,0x10
+ li r9,0x10
+
 .align 5
 L8x_round_loop:
- lxvd2x VSR(K),r10,KEYS
+ lxvd2x VSR(K),r9,KEYS
  vperm   K,K,K,SWAP_MASK
  OPN_XXY(vncipher, ZERO, S0, S1, S2, S3, S4, S5, S6, S7)
  OPN_XXY(vxor, K, S0, S1, S2, S3, S4, S5, S6, S7)
- addi r10,r10,0x10
+ addi r9,r9,0x10
  bdnz L8x_round_loop
 
- lxvd2x VSR(K),r10,KEYS
+ lxvd2x VSR(K),r9,KEYS
  vperm   K,K,K,SWAP_MASK
  OPN_XXY(vncipherlast, K, S0, S1, S2, S3, S4, S5, S6, S7)
 
 IF_LE(`OPN_XXXY(vperm, SWAP_MASK, S0,S1,S2,S3,S4,S5,S6,S7)')
 
  stxvd2x VSR(S0),0,DST
- stxvd2x VSR(S1),r25,DST
- stxvd2x VSR(S2),r26,DST
- stxvd2x VSR(S3),r27,DST
- stxvd2x VSR(S4),r28,DST
- stxvd2x VSR(S5),r29,DST
- stxvd2x VSR(S6),r30,DST
- stxvd2x VSR(S7),r31,DST
+ stxvd2x VSR(S1),r10,DST
+ stxvd2x VSR(S2),r11,DST
+ stxvd2x VSR(S3),r12,DST
+ stxvd2x VSR(S4),r14,DST
+ stxvd2x VSR(S5),r15,DST
+ stxvd2x VSR(S6),r16,DST
+ stxvd2x VSR(S7),r17,DST
 
  addi SRC,SRC,0x80
  addi DST,DST,0x80
+
  subic. r5,r5,1
  bne Lx8_loop
 
- ld r25,-56(SP)
- ld r26,-48(SP)
- ld r27,-40(SP)
- ld r28,-32(SP)
- ld r29,-24(SP)
- ld r30,-16(SP)
- ld r31,-8(SP)
+ ld r14,-32(SP)
+ ld r15,-24(SP)
+ ld r16,-16(SP)
+ ld r17,-8(SP)
 
  clrldi LENGTH,LENGTH,61
 
@@ -164,41 +163,35 @@ L4x:
  vperm   K,K,K,SWAP_MASK
 
  lxvd2x VSR(S0),0,SRC
- li  r9,0x10
- lxvd2x VSR(S1),r9,SRC
- addi   r9,r9,0x10
- lxvd2x VSR(S2),r9,SRC
- addi   r9,r9,0x10
- lxvd2x VSR(S3),r9,SRC
+ lxvd2x VSR(S1),r10,SRC
+ lxvd2x VSR(S2),r11,SRC
+ lxvd2x VSR(S3),r12,SRC
 
 IF_LE(`OPN_XXXY(vperm, SWAP_MASK, S0,S1,S2,S3)')
 
  OPN_XXY(vxor, K, S0, S1, S2, S3)
 
  mtctr ROUNDS
- li r10,0x10
+ li r9,0x10
 .align 5
 L4x_round_loop:
- lxvd2x VSR(K),r10,KEYS
+ lxvd2x VSR(K),r9,KEYS
  vperm  K,K,K,SWAP_MASK
  OPN_XXY(vncipher, ZERO, S0, S1, S2, S3)
  OPN_XXY(vxor, K, S0, S1, S2, S3)
- addi   r10,r10,0x10
+ addi   r9,r9,0x10
  bdnz  L4x_round_loop
 
- lxvd2x VSR(K),r10,KEYS
+ lxvd2x VSR(K),r9,KEYS
  vperm   K,K,K,SWAP_MASK
  OPN_XXY(vncipherlast, K, S0, S1, S2, S3)
 
 IF_LE(`OPN_XXXY(vperm, SWAP_MASK, S0,S1,S2,S3)')
 
  stxvd2x VSR(S0),0,DST
- li  r9,0x10
- stxvd2x VSR(S1),r9,DST
- addi   r9,r9,0x10
- stxvd2x VSR(S2),r9,DST
- addi  r9,r9,0x10
- stxvd2x VSR(S3),r9,DST
+ stxvd2x VSR(S1),r10,DST
+ stxvd2x VSR(S2),r11,DST
+ stxvd2x VSR(S3),r12,DST
 
  addi   SRC,SRC,0x40
  addi   DST,DST,0x40
@@ -214,8 +207,7 @@ L2x:
  vperm K,K,K,SWAP_MASK
 
  lxvd2x VSR(S0),0,SRC
- li   r9,0x10
- lxvd2x VSR(S1),r9,SRC
+ lxvd2x VSR(S1),r10,SRC
 
 IF_LE(`vperm S0,S0,S0,SWAP_MASK
  vperm S1,S1,S1,SWAP_MASK')
@@ -224,19 +216,19 @@ IF_LE(`vperm S0,S0,S0,SWAP_MASK
  vxor   S1,S1,K
 
  mtctr   ROUNDS
- li  r10,0x10
+ li  r9,0x10
 .align 5
 L2x_round_loop:
- lxvd2x VSR(K),r10,KEYS
+ lxvd2x VSR(K),r9,KEYS
  vperm  K,K,K,SWAP_MASK
  vncipher S0,S0,ZERO
  vncipher S1,S1,ZERO
  vxor  S0,S0,K
  vxor  S1,S1,K
- addi   r10,r10,0x10
+ addi   r9,r9,0x10
  bdnz   L2x_round_loop
 
- lxvd2x VSR(K),r10,KEYS
+ lxvd2x VSR(K),r9,KEYS
  vperm  K,K,K,SWAP_MASK
  vncipherlast S0,S0,K
  vncipherlast S1,S1,K
@@ -245,8 +237,7 @@ IF_LE(`vperm S0,S0,S0,SWAP_MASK
  vperm S1,S1,S1,SWAP_MASK')
 
  stxvd2x VSR(S0),0,DST
- li  r9,0x10
- stxvd2x VSR(S1),r9,DST
+ stxvd2x VSR(S1),r10,DST
 
  addi   SRC,SRC,0x20
  addi   DST,DST,0x20
@@ -267,17 +258,17 @@ IF_LE(`vperm S0,S0,S0,SWAP_MASK')
  vxor   S0,S0,K
 
  mtctr   ROUNDS
- li   r10,0x10
+ li   r9,0x10
 .align 5
 L1x_round_loop:
- lxvd2x VSR(K),r10,KEYS
+ lxvd2x VSR(K),r9,KEYS
  vperm  K,K,K,SWAP_MASK
  vncipher S0,S0,ZERO
  vxor   S0,S0,K
- addi   r10,r10,0x10
+ addi   r9,r9,0x10
  bdnz   L1x_round_loop
 
- lxvd2x VSR(K),r10,KEYS
+ lxvd2x VSR(K),r9,KEYS
  vperm  K,K,K,SWAP_MASK
  vncipherlast S0,S0,K
 
diff --git a/powerpc64/p8/aes-encrypt-internal.asm b/powerpc64/p8/aes-encrypt-internal.asm
index 9ae8bc0e9836e8ee7b3ab7f4ff9b63ad09346412..1af50b1479e15c5c31e6825921cbd9c01b9c3129 100644
--- a/powerpc64/p8/aes-encrypt-internal.asm
+++ b/powerpc64/p8/aes-encrypt-internal.asm
@@ -39,6 +39,7 @@ define(`KEYS', `r4')
 define(`LENGTH', `r6')
 define(`DST', `r7')
 define(`SRC', `r8')
+C r9 used as loop index register, r10-r12, r14-r17 as constants.
 
 define(`SWAP_MASK', `v0')
 
@@ -68,25 +69,24 @@ PROLOGUE(_nettle_aes_encrypt)
  subi ROUNDS,ROUNDS,1
  srdi LENGTH,LENGTH,4
 
+ C Used as offsets for load/store, throughout this function
+ li             r10,0x10
+ li             r11,0x20
+ li             r12,0x30
+
  srdi r5,LENGTH,3 #8x loop count
  cmpldi r5,0
  beq L4x
 
- std r25,-56(SP)
- std r26,-48(SP)
- std r27,-40(SP)
- std r28,-32(SP)
- std r29,-24(SP)
- std r30,-16(SP)
- std r31,-8(SP)
-
- li r25,0x10
- li r26,0x20
- li r27,0x30
- li r28,0x40
- li r29,0x50
- li r30,0x60
- li r31,0x70
+ std r14,-32(SP)
+ std r15,-24(SP)
+ std r16,-16(SP)
+ std r17,-8(SP)
+
+ li r14,0x40
+ li r15,0x50
+ li r16,0x60
+ li r17,0x70
 
 .align 5
 Lx8_loop:
@@ -94,55 +94,54 @@ Lx8_loop:
  vperm   K,K,K,SWAP_MASK
 
  lxvd2x VSR(S0),0,SRC
- lxvd2x VSR(S1),r25,SRC
- lxvd2x VSR(S2),r26,SRC
- lxvd2x VSR(S3),r27,SRC
- lxvd2x VSR(S4),r28,SRC
- lxvd2x VSR(S5),r29,SRC
- lxvd2x VSR(S6),r30,SRC
- lxvd2x VSR(S7),r31,SRC
+ lxvd2x VSR(S1),r10,SRC
+ lxvd2x VSR(S2),r11,SRC
+ lxvd2x VSR(S3),r12,SRC
+ lxvd2x VSR(S4),r14,SRC
+ lxvd2x VSR(S5),r15,SRC
+ lxvd2x VSR(S6),r16,SRC
+ lxvd2x VSR(S7),r17,SRC
 
 IF_LE(`OPN_XXXY(vperm, SWAP_MASK, S0,S1,S2,S3,S4,S5,S6,S7)')
 
  OPN_XXY(vxor, K, S0, S1, S2, S3, S4, S5, S6, S7)
 
  mtctr ROUNDS
- li r10,0x10
+ li r9,0x10
+
 .align 5
 L8x_round_loop:
- lxvd2x VSR(K),r10,KEYS
+ lxvd2x VSR(K),r9,KEYS
  vperm   K,K,K,SWAP_MASK
  OPN_XXY(vcipher, K, S0, S1, S2, S3, S4, S5, S6, S7)
- addi r10,r10,0x10
+ addi r9,r9,0x10
  bdnz L8x_round_loop
 
- lxvd2x VSR(K),r10,KEYS
+ lxvd2x VSR(K),r9,KEYS
  vperm   K,K,K,SWAP_MASK
  OPN_XXY(vcipherlast, K, S0, S1, S2, S3, S4, S5, S6, S7)
 
 IF_LE(`OPN_XXXY(vperm, SWAP_MASK, S0,S1,S2,S3,S4,S5,S6,S7)')
 
  stxvd2x VSR(S0),0,DST
- stxvd2x VSR(S1),r25,DST
- stxvd2x VSR(S2),r26,DST
- stxvd2x VSR(S3),r27,DST
- stxvd2x VSR(S4),r28,DST
- stxvd2x VSR(S5),r29,DST
- stxvd2x VSR(S6),r30,DST
- stxvd2x VSR(S7),r31,DST
+ stxvd2x VSR(S1),r10,DST
+ stxvd2x VSR(S2),r11,DST
+ stxvd2x VSR(S3),r12,DST
+ stxvd2x VSR(S4),r14,DST
+ stxvd2x VSR(S5),r15,DST
+ stxvd2x VSR(S6),r16,DST
+ stxvd2x VSR(S7),r17,DST
 
  addi SRC,SRC,0x80
  addi DST,DST,0x80
+
  subic. r5,r5,1
  bne Lx8_loop
 
- ld r25,-56(SP)
- ld r26,-48(SP)
- ld r27,-40(SP)
- ld r28,-32(SP)
- ld r29,-24(SP)
- ld r30,-16(SP)
- ld r31,-8(SP)
+ ld r14,-32(SP)
+ ld r15,-24(SP)
+ ld r16,-16(SP)
+ ld r17,-8(SP)
 
  clrldi LENGTH,LENGTH,61
 
@@ -155,40 +154,34 @@ L4x:
  vperm   K,K,K,SWAP_MASK
 
  lxvd2x VSR(S0),0,SRC
- li  r9,0x10
- lxvd2x VSR(S1),r9,SRC
- addi   r9,r9,0x10
- lxvd2x VSR(S2),r9,SRC
- addi   r9,r9,0x10
- lxvd2x VSR(S3),r9,SRC
+ lxvd2x VSR(S1),r10,SRC
+ lxvd2x VSR(S2),r11,SRC
+ lxvd2x VSR(S3),r12,SRC
 
 IF_LE(`OPN_XXXY(vperm, SWAP_MASK, S0,S1,S2,S3)')
 
  OPN_XXY(vxor, K, S0, S1, S2, S3)
 
  mtctr ROUNDS
- li r10,0x10
+ li r9,0x10
 .align 5
 L4x_round_loop:
- lxvd2x VSR(K),r10,KEYS
+ lxvd2x VSR(K),r9,KEYS
  vperm  K,K,K,SWAP_MASK
  OPN_XXY(vcipher, K, S0, S1, S2, S3)
- addi   r10,r10,0x10
+ addi   r9,r9,0x10
  bdnz  L4x_round_loop
 
- lxvd2x VSR(K),r10,KEYS
+ lxvd2x VSR(K),r9,KEYS
  vperm   K,K,K,SWAP_MASK
  OPN_XXY(vcipherlast, K, S0, S1, S2, S3)
 
 IF_LE(`OPN_XXXY(vperm, SWAP_MASK, S0,S1,S2,S3)')
 
  stxvd2x VSR(S0),0,DST
- li  r9,0x10
- stxvd2x VSR(S1),r9,DST
- addi   r9,r9,0x10
- stxvd2x VSR(S2),r9,DST
- addi  r9,r9,0x10
- stxvd2x VSR(S3),r9,DST
+ stxvd2x VSR(S1),r10,DST
+ stxvd2x VSR(S2),r11,DST
+ stxvd2x VSR(S3),r12,DST
 
  addi   SRC,SRC,0x40
  addi   DST,DST,0x40
@@ -204,8 +197,7 @@ L2x:
  vperm K,K,K,SWAP_MASK
 
  lxvd2x VSR(S0),0,SRC
- li   r9,0x10
- lxvd2x VSR(S1),r9,SRC
+ lxvd2x VSR(S1),r10,SRC
 
 IF_LE(`vperm S0,S0,S0,SWAP_MASK
  vperm S1,S1,S1,SWAP_MASK')
@@ -214,17 +206,17 @@ IF_LE(`vperm S0,S0,S0,SWAP_MASK
  vxor   S1,S1,K
 
  mtctr   ROUNDS
- li  r10,0x10
+ li  r9,0x10
 .align 5
 L2x_round_loop:
- lxvd2x VSR(K),r10,KEYS
+ lxvd2x VSR(K),r9,KEYS
  vperm  K,K,K,SWAP_MASK
  vcipher S0,S0,K
  vcipher S1,S1,K
- addi   r10,r10,0x10
+ addi   r9,r9,0x10
  bdnz   L2x_round_loop
 
- lxvd2x VSR(K),r10,KEYS
+ lxvd2x VSR(K),r9,KEYS
  vperm  K,K,K,SWAP_MASK
  vcipherlast S0,S0,K
  vcipherlast S1,S1,K
@@ -233,8 +225,7 @@ IF_LE(`vperm S0,S0,S0,SWAP_MASK
  vperm S1,S1,S1,SWAP_MASK')
 
  stxvd2x VSR(S0),0,DST
- li  r9,0x10
- stxvd2x VSR(S1),r9,DST
+ stxvd2x VSR(S1),r10,DST
 
  addi   SRC,SRC,0x20
  addi   DST,DST,0x20
@@ -255,16 +246,16 @@ IF_LE(`vperm S0,S0,S0,SWAP_MASK')
  vxor   S0,S0,K
 
  mtctr   ROUNDS
- li   r10,0x10
+ li   r9,0x10
 .align 5
 L1x_round_loop:
- lxvd2x VSR(K),r10,KEYS
+ lxvd2x VSR(K),r9,KEYS
  vperm  K,K,K,SWAP_MASK
  vcipher S0,S0,K
- addi   r10,r10,0x10
+ addi   r9,r9,0x10
  bdnz   L1x_round_loop
 
- lxvd2x VSR(K),r10,KEYS
+ lxvd2x VSR(K),r9,KEYS
  vperm  K,K,K,SWAP_MASK
  vcipherlast S0,S0,K