%verify "executed" /* * Signed 64-bit integer multiply. * * Consider WXxYZ (r1r0 x r3r2) with a long multiply: * WX * x YZ * -------- * ZW ZX * YW YX * * The low word of the result holds ZX, the high word holds * (ZW+YX) + (the high overflow from ZX). YW doesn't matter because * it doesn't fit in the low 64 bits. * * Unlike most ARM math operations, multiply instructions have * restrictions on using the same register more than once (Rd and Rm * cannot be the same). */ /* mul-long vAA, vBB, vCC */ FETCH(r0, 1) @ r0<- CCBB and r2, r0, #255 @ r2<- BB mov r3, r0, lsr #8 @ r3<- CC add r2, rFP, r2, lsl #2 @ r2<- &fp[BB] add r3, rFP, r3, lsl #2 @ r3<- &fp[CC] ldmia r2, {r0-r1} @ r0/r1<- vBB/vBB+1 ldmia r3, {r2-r3} @ r2/r3<- vCC/vCC+1 mul ip, r2, r1 @ ip<- ZxW umull r9, r10, r2, r0 @ r9/r10 <- ZxX mla r2, r0, r3, ip @ r2<- YxX + (ZxW) mov r0, rINST, lsr #8 @ r0<- AA add r10, r2, r10 @ r10<- r10 + low(ZxW + (YxX)) add r0, rFP, r0, lsl #2 @ r0<- &fp[AA] FETCH_ADVANCE_INST(2) @ advance rPC, load rINST b .L${opcode}_finish %break .L${opcode}_finish: GET_INST_OPCODE(ip) @ extract opcode from rINST stmia r0, {r9-r10} @ vAA/vAA+1<- r9/r10 GOTO_OPCODE(ip) @ jump to next instruction