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1%verify "executed"
2    /*
3     * Signed 64-bit integer multiply.
4     *
5     * Consider WXxYZ (r1r0 x r3r2) with a long multiply:
6     *        WX
7     *      x YZ
8     *  --------
9     *     ZW ZX
10     *  YW YX
11     *
12     * The low word of the result holds ZX, the high word holds
13     * (ZW+YX) + (the high overflow from ZX).  YW doesn't matter because
14     * it doesn't fit in the low 64 bits.
15     *
16     * Unlike most ARM math operations, multiply instructions have
17     * restrictions on using the same register more than once (Rd and Rm
18     * cannot be the same).
19     */
20    /* mul-long vAA, vBB, vCC */
21    FETCH(r0, 1)                        @ r0<- CCBB
22    and     r2, r0, #255                @ r2<- BB
23    mov     r3, r0, lsr #8              @ r3<- CC
24    add     r2, rFP, r2, lsl #2         @ r2<- &fp[BB]
25    add     r3, rFP, r3, lsl #2         @ r3<- &fp[CC]
26    ldmia   r2, {r0-r1}                 @ r0/r1<- vBB/vBB+1
27    ldmia   r3, {r2-r3}                 @ r2/r3<- vCC/vCC+1
28    mul     ip, r2, r1                  @  ip<- ZxW
29    umull   r9, r10, r2, r0             @  r9/r10 <- ZxX
30    mla     r2, r0, r3, ip              @  r2<- YxX + (ZxW)
31    mov     r0, rINST, lsr #8           @ r0<- AA
32    add     r10, r2, r10                @  r10<- r10 + low(ZxW + (YxX))
33    add     r0, rFP, r0, lsl #2         @ r0<- &fp[AA]
34    FETCH_ADVANCE_INST(2)               @ advance rPC, load rINST
35    b       .L${opcode}_finish
36%break
37
38.L${opcode}_finish:
39    GET_INST_OPCODE(ip)                 @ extract opcode from rINST
40    stmia   r0, {r9-r10}                @ vAA/vAA+1<- r9/r10
41    GOTO_OPCODE(ip)                     @ jump to next instruction
42