salsa20/salsa: fix amd64 assembly not to smash SP
For golang/go#44269.
Change-Id: Ica352261d696317addbdd422d4cde5bf07fef839
Reviewed-on: https://go-review.googlesource.com/c/crypto/+/292050
Trust: Russ Cox <rsc@golang.org>
Trust: Jason A. Donenfeld <Jason@zx2c4.com>
Reviewed-by: Jason A. Donenfeld <Jason@zx2c4.com>
diff --git a/salsa20/salsa/salsa20_amd64.s b/salsa20/salsa/salsa20_amd64.s
index 9c84012..f97efc6 100644
--- a/salsa20/salsa/salsa20_amd64.s
+++ b/salsa20/salsa/salsa20_amd64.s
@@ -8,7 +8,7 @@
// domain sources in SUPERCOP: https://bench.cr.yp.to/supercop.html
// func salsa2020XORKeyStream(out, in *byte, n uint64, nonce, key *byte)
-// This needs up to 64 bytes at 360(SP); hence the non-obvious frame size.
+// This needs up to 64 bytes at 360(R12); hence the non-obvious frame size.
TEXT ·salsa2020XORKeyStream(SB),0,$456-40 // frame = 424 + 32 byte alignment
MOVQ out+0(FP),DI
MOVQ in+8(FP),SI
@@ -17,10 +17,8 @@
MOVQ key+32(FP),R8
MOVQ SP,R12
- MOVQ SP,R9
- ADDQ $31, R9
- ANDQ $~31, R9
- MOVQ R9, SP
+ ADDQ $31, R12
+ ANDQ $~31, R12
MOVQ DX,R9
MOVQ CX,DX
@@ -32,116 +30,116 @@
MOVL 0(R10),R8
MOVL 0(DX),AX
MOVL 16(R10),R11
- MOVL CX,0(SP)
- MOVL R8, 4 (SP)
- MOVL AX, 8 (SP)
- MOVL R11, 12 (SP)
+ MOVL CX,0(R12)
+ MOVL R8, 4 (R12)
+ MOVL AX, 8 (R12)
+ MOVL R11, 12 (R12)
MOVL 8(DX),CX
MOVL 24(R10),R8
MOVL 4(R10),AX
MOVL 4(DX),R11
- MOVL CX,16(SP)
- MOVL R8, 20 (SP)
- MOVL AX, 24 (SP)
- MOVL R11, 28 (SP)
+ MOVL CX,16(R12)
+ MOVL R8, 20 (R12)
+ MOVL AX, 24 (R12)
+ MOVL R11, 28 (R12)
MOVL 12(DX),CX
MOVL 12(R10),DX
MOVL 28(R10),R8
MOVL 8(R10),AX
- MOVL DX,32(SP)
- MOVL CX, 36 (SP)
- MOVL R8, 40 (SP)
- MOVL AX, 44 (SP)
+ MOVL DX,32(R12)
+ MOVL CX, 36 (R12)
+ MOVL R8, 40 (R12)
+ MOVL AX, 44 (R12)
MOVQ $1634760805,DX
MOVQ $857760878,CX
MOVQ $2036477234,R8
MOVQ $1797285236,AX
- MOVL DX,48(SP)
- MOVL CX, 52 (SP)
- MOVL R8, 56 (SP)
- MOVL AX, 60 (SP)
+ MOVL DX,48(R12)
+ MOVL CX, 52 (R12)
+ MOVL R8, 56 (R12)
+ MOVL AX, 60 (R12)
CMPQ R9,$256
JB BYTESBETWEEN1AND255
- MOVOA 48(SP),X0
+ MOVOA 48(R12),X0
PSHUFL $0X55,X0,X1
PSHUFL $0XAA,X0,X2
PSHUFL $0XFF,X0,X3
PSHUFL $0X00,X0,X0
- MOVOA X1,64(SP)
- MOVOA X2,80(SP)
- MOVOA X3,96(SP)
- MOVOA X0,112(SP)
- MOVOA 0(SP),X0
+ MOVOA X1,64(R12)
+ MOVOA X2,80(R12)
+ MOVOA X3,96(R12)
+ MOVOA X0,112(R12)
+ MOVOA 0(R12),X0
PSHUFL $0XAA,X0,X1
PSHUFL $0XFF,X0,X2
PSHUFL $0X00,X0,X3
PSHUFL $0X55,X0,X0
- MOVOA X1,128(SP)
- MOVOA X2,144(SP)
- MOVOA X3,160(SP)
- MOVOA X0,176(SP)
- MOVOA 16(SP),X0
+ MOVOA X1,128(R12)
+ MOVOA X2,144(R12)
+ MOVOA X3,160(R12)
+ MOVOA X0,176(R12)
+ MOVOA 16(R12),X0
PSHUFL $0XFF,X0,X1
PSHUFL $0X55,X0,X2
PSHUFL $0XAA,X0,X0
- MOVOA X1,192(SP)
- MOVOA X2,208(SP)
- MOVOA X0,224(SP)
- MOVOA 32(SP),X0
+ MOVOA X1,192(R12)
+ MOVOA X2,208(R12)
+ MOVOA X0,224(R12)
+ MOVOA 32(R12),X0
PSHUFL $0X00,X0,X1
PSHUFL $0XAA,X0,X2
PSHUFL $0XFF,X0,X0
- MOVOA X1,240(SP)
- MOVOA X2,256(SP)
- MOVOA X0,272(SP)
+ MOVOA X1,240(R12)
+ MOVOA X2,256(R12)
+ MOVOA X0,272(R12)
BYTESATLEAST256:
- MOVL 16(SP),DX
- MOVL 36 (SP),CX
- MOVL DX,288(SP)
- MOVL CX,304(SP)
+ MOVL 16(R12),DX
+ MOVL 36 (R12),CX
+ MOVL DX,288(R12)
+ MOVL CX,304(R12)
SHLQ $32,CX
ADDQ CX,DX
ADDQ $1,DX
MOVQ DX,CX
SHRQ $32,CX
- MOVL DX, 292 (SP)
- MOVL CX, 308 (SP)
+ MOVL DX, 292 (R12)
+ MOVL CX, 308 (R12)
ADDQ $1,DX
MOVQ DX,CX
SHRQ $32,CX
- MOVL DX, 296 (SP)
- MOVL CX, 312 (SP)
+ MOVL DX, 296 (R12)
+ MOVL CX, 312 (R12)
ADDQ $1,DX
MOVQ DX,CX
SHRQ $32,CX
- MOVL DX, 300 (SP)
- MOVL CX, 316 (SP)
+ MOVL DX, 300 (R12)
+ MOVL CX, 316 (R12)
ADDQ $1,DX
MOVQ DX,CX
SHRQ $32,CX
- MOVL DX,16(SP)
- MOVL CX, 36 (SP)
- MOVQ R9,352(SP)
+ MOVL DX,16(R12)
+ MOVL CX, 36 (R12)
+ MOVQ R9,352(R12)
MOVQ $20,DX
- MOVOA 64(SP),X0
- MOVOA 80(SP),X1
- MOVOA 96(SP),X2
- MOVOA 256(SP),X3
- MOVOA 272(SP),X4
- MOVOA 128(SP),X5
- MOVOA 144(SP),X6
- MOVOA 176(SP),X7
- MOVOA 192(SP),X8
- MOVOA 208(SP),X9
- MOVOA 224(SP),X10
- MOVOA 304(SP),X11
- MOVOA 112(SP),X12
- MOVOA 160(SP),X13
- MOVOA 240(SP),X14
- MOVOA 288(SP),X15
+ MOVOA 64(R12),X0
+ MOVOA 80(R12),X1
+ MOVOA 96(R12),X2
+ MOVOA 256(R12),X3
+ MOVOA 272(R12),X4
+ MOVOA 128(R12),X5
+ MOVOA 144(R12),X6
+ MOVOA 176(R12),X7
+ MOVOA 192(R12),X8
+ MOVOA 208(R12),X9
+ MOVOA 224(R12),X10
+ MOVOA 304(R12),X11
+ MOVOA 112(R12),X12
+ MOVOA 160(R12),X13
+ MOVOA 240(R12),X14
+ MOVOA 288(R12),X15
MAINLOOP1:
- MOVOA X1,320(SP)
- MOVOA X2,336(SP)
+ MOVOA X1,320(R12)
+ MOVOA X2,336(R12)
MOVOA X13,X1
PADDL X12,X1
MOVOA X1,X2
@@ -191,8 +189,8 @@
PXOR X1,X12
PSRLL $14,X2
PXOR X2,X12
- MOVOA 320(SP),X1
- MOVOA X12,320(SP)
+ MOVOA 320(R12),X1
+ MOVOA X12,320(R12)
MOVOA X9,X2
PADDL X7,X2
MOVOA X2,X12
@@ -207,8 +205,8 @@
PXOR X2,X3
PSRLL $25,X12
PXOR X12,X3
- MOVOA 336(SP),X2
- MOVOA X0,336(SP)
+ MOVOA 336(R12),X2
+ MOVOA X0,336(R12)
MOVOA X6,X0
PADDL X2,X0
MOVOA X0,X12
@@ -251,8 +249,8 @@
PXOR X0,X1
PSRLL $14,X12
PXOR X12,X1
- MOVOA 320(SP),X0
- MOVOA X1,320(SP)
+ MOVOA 320(R12),X0
+ MOVOA X1,320(R12)
MOVOA X4,X1
PADDL X0,X1
MOVOA X1,X12
@@ -267,8 +265,8 @@
PXOR X1,X2
PSRLL $14,X12
PXOR X12,X2
- MOVOA 336(SP),X12
- MOVOA X2,336(SP)
+ MOVOA 336(R12),X12
+ MOVOA X2,336(R12)
MOVOA X14,X1
PADDL X12,X1
MOVOA X1,X2
@@ -311,8 +309,8 @@
PXOR X1,X0
PSRLL $14,X2
PXOR X2,X0
- MOVOA 320(SP),X1
- MOVOA X0,320(SP)
+ MOVOA 320(R12),X1
+ MOVOA X0,320(R12)
MOVOA X8,X0
PADDL X14,X0
MOVOA X0,X2
@@ -327,8 +325,8 @@
PXOR X0,X6
PSRLL $25,X2
PXOR X2,X6
- MOVOA 336(SP),X2
- MOVOA X12,336(SP)
+ MOVOA 336(R12),X2
+ MOVOA X12,336(R12)
MOVOA X3,X0
PADDL X2,X0
MOVOA X0,X12
@@ -378,14 +376,14 @@
PXOR X0,X2
PSRLL $14,X12
PXOR X12,X2
- MOVOA 320(SP),X12
- MOVOA 336(SP),X0
+ MOVOA 320(R12),X12
+ MOVOA 336(R12),X0
SUBQ $2,DX
JA MAINLOOP1
- PADDL 112(SP),X12
- PADDL 176(SP),X7
- PADDL 224(SP),X10
- PADDL 272(SP),X4
+ PADDL 112(R12),X12
+ PADDL 176(R12),X7
+ PADDL 224(R12),X10
+ PADDL 272(R12),X4
MOVD X12,DX
MOVD X7,CX
MOVD X10,R8
@@ -446,10 +444,10 @@
MOVL CX,196(DI)
MOVL R8,200(DI)
MOVL R9,204(DI)
- PADDL 240(SP),X14
- PADDL 64(SP),X0
- PADDL 128(SP),X5
- PADDL 192(SP),X8
+ PADDL 240(R12),X14
+ PADDL 64(R12),X0
+ PADDL 128(R12),X5
+ PADDL 192(R12),X8
MOVD X14,DX
MOVD X0,CX
MOVD X5,R8
@@ -510,10 +508,10 @@
MOVL CX,212(DI)
MOVL R8,216(DI)
MOVL R9,220(DI)
- PADDL 288(SP),X15
- PADDL 304(SP),X11
- PADDL 80(SP),X1
- PADDL 144(SP),X6
+ PADDL 288(R12),X15
+ PADDL 304(R12),X11
+ PADDL 80(R12),X1
+ PADDL 144(R12),X6
MOVD X15,DX
MOVD X11,CX
MOVD X1,R8
@@ -574,10 +572,10 @@
MOVL CX,228(DI)
MOVL R8,232(DI)
MOVL R9,236(DI)
- PADDL 160(SP),X13
- PADDL 208(SP),X9
- PADDL 256(SP),X3
- PADDL 96(SP),X2
+ PADDL 160(R12),X13
+ PADDL 208(R12),X9
+ PADDL 256(R12),X3
+ PADDL 96(R12),X2
MOVD X13,DX
MOVD X9,CX
MOVD X3,R8
@@ -638,7 +636,7 @@
MOVL CX,244(DI)
MOVL R8,248(DI)
MOVL R9,252(DI)
- MOVQ 352(SP),R9
+ MOVQ 352(R12),R9
SUBQ $256,R9
ADDQ $256,SI
ADDQ $256,DI
@@ -650,17 +648,17 @@
CMPQ R9,$64
JAE NOCOPY
MOVQ DI,DX
- LEAQ 360(SP),DI
+ LEAQ 360(R12),DI
MOVQ R9,CX
REP; MOVSB
- LEAQ 360(SP),DI
- LEAQ 360(SP),SI
+ LEAQ 360(R12),DI
+ LEAQ 360(R12),SI
NOCOPY:
- MOVQ R9,352(SP)
- MOVOA 48(SP),X0
- MOVOA 0(SP),X1
- MOVOA 16(SP),X2
- MOVOA 32(SP),X3
+ MOVQ R9,352(R12)
+ MOVOA 48(R12),X0
+ MOVOA 0(R12),X1
+ MOVOA 16(R12),X2
+ MOVOA 32(R12),X3
MOVOA X1,X4
MOVQ $20,CX
MAINLOOP2:
@@ -791,10 +789,10 @@
PSHUFL $0X39,X3,X3
PXOR X6,X0
JA MAINLOOP2
- PADDL 48(SP),X0
- PADDL 0(SP),X1
- PADDL 16(SP),X2
- PADDL 32(SP),X3
+ PADDL 48(R12),X0
+ PADDL 0(R12),X1
+ PADDL 16(R12),X2
+ PADDL 32(R12),X3
MOVD X0,CX
MOVD X1,R8
MOVD X2,R9
@@ -855,16 +853,16 @@
MOVL R8,44(DI)
MOVL R9,28(DI)
MOVL AX,12(DI)
- MOVQ 352(SP),R9
- MOVL 16(SP),CX
- MOVL 36 (SP),R8
+ MOVQ 352(R12),R9
+ MOVL 16(R12),CX
+ MOVL 36 (R12),R8
ADDQ $1,CX
SHLQ $32,R8
ADDQ R8,CX
MOVQ CX,R8
SHRQ $32,R8
- MOVL CX,16(SP)
- MOVL R8, 36 (SP)
+ MOVL CX,16(R12)
+ MOVL R8, 36 (R12)
CMPQ R9,$64
JA BYTESATLEAST65
JAE BYTESATLEAST64
@@ -874,7 +872,6 @@
REP; MOVSB
BYTESATLEAST64:
DONE:
- MOVQ R12,SP
RET
BYTESATLEAST65:
SUBQ $64,R9
