ref: 2efaa1c5d93983daf4a4541a3c196bda4d4bb5fd
dir: /sys/src/libsec/amd64/chachablock.s/
#define ROTATE(n, v1, v2) \ MOVO v1, v2; \ PSLLL $(n), v1; \ PSRLL $(32-n), v2; \ POR v1, v2 TEXT _chachablock(SB), 0, $0 MOVOU 0(RARG), X0 MOVOU 16(RARG), X1 MOVOU 32(RARG), X2 MOVOU 48(RARG), X3 MOVL rounds+8(FP), CX SHRL $1, CX _loop: PADDL X1, X0 PXOR X0, X3 /* ROTATE(16, X3, X3) */ PSHUFLW $(1<<0 | 0<<2 | 3<<4 | 2<<6), X3, X3 PSHUFHW $(1<<0 | 0<<2 | 3<<4 | 2<<6), X3, X3 PADDL X3, X2 MOVO X1, X4 PXOR X2, X4 ROTATE(12, X4, X1) PADDL X1, X0 MOVO X0, X4 PXOR X3, X4 ROTATE(8, X4, X3) PADDL X3, X2 MOVO X1, X4 PXOR X2, X4 ROTATE(7, X4, X1) PSHUFL $(1<<0 | 2<<2 | 3<<4 | 0<<6), X1, X1 PSHUFL $(2<<0 | 3<<2 | 0<<4 | 1<<6), X2, X2 PSHUFL $(3<<0 | 0<<2 | 1<<4 | 2<<6), X3, X3 PADDL X1, X0 PXOR X0, X3 /* ROTATE(16, X3, X3) */ PSHUFLW $(1<<0 | 0<<2 | 3<<4 | 2<<6), X3, X3 PSHUFHW $(1<<0 | 0<<2 | 3<<4 | 2<<6), X3, X3 PADDL X3, X2 MOVO X1, X4 PXOR X2, X4 ROTATE(12, X4, X1) PADDL X1, X0 MOVO X0, X4 PXOR X3, X4 ROTATE(8, X4, X3) PADDL X3, X2 MOVO X1, X4 PXOR X2, X4 ROTATE(7, X4, X1) PSHUFL $(3<<0 | 0<<2 | 1<<4 | 2<<6), X1, X1 PSHUFL $(2<<0 | 3<<2 | 0<<4 | 1<<6), X2, X2 PSHUFL $(1<<0 | 2<<2 | 3<<4 | 0<<6), X3, X3 DECL CX JNE _loop MOVOU X0, 0(RARG) MOVOU X1, 16(RARG) MOVOU X2, 32(RARG) MOVOU X3, 48(RARG) RET