ref: e11c7aa718df592bd69de53ce1d6498cc870f256
dir: /libkern/vlop-thumb.s/
#define UMULL(Rs,Rm,Rhi,Rlo,S) WORD $((14<<28)|(4<<21)|(S<<20)|(Rhi<<16)|(Rlo<<12)|(Rs<<8)|(9<<4)|Rm) #define UMLAL(Rs,Rm,Rhi,Rlo,S) WORD $((14<<28)|(5<<21)|(S<<20)|(Rhi<<16)|(Rlo<<12)|(Rs<<8)|(9<<4)|Rm) #define MUL(Rs,Rm,Rd,S) WORD $((14<<28)|(0<<21)|(S<<20)|(Rd<<16)|(Rs<<8)|(9<<4)|Rm) arg=0 /* replaced use of R10 by R11 because the former can be the data segment base register */ TEXT _mulv(SB), $0 MOVW 4(FP), R9 /* l0 */ MOVW 8(FP), R11 /* h0 */ MOVW 12(FP), R4 /* l1 */ MOVW 16(FP), R5 /* h1 */ UMULL(4, 9, 7, 6, 0) MUL(11, 4, 8, 0) ADD R8, R7 MUL(9, 5, 8, 0) ADD R8, R7 MOVW R6, 0(R(arg)) MOVW R7, 4(R(arg)) RET /* multiply, add, and right-shift, yielding a 32-bit result, while using 64-bit accuracy for the multiply -- for fast fixed-point math */ TEXT _mularsv(SB), $0 MOVW 4(FP), R11 /* m1 */ MOVW 8(FP), R8 /* a */ MOVW 12(FP), R4 /* rs */ MOVW $0, R9 UMLAL(0, 11, 9, 8, 0) MOVW R8>>R4, R8 RSB $32, R4, R4 ORR R9<<R4, R8, R0 RET