1%default {"preinstr":"", "result":"a0", "chkzero":"0"}
2    /*
3     * Generic 32-bit "/2addr" binary operation.  Provide an "instr" line
4     * that specifies an instruction that performs "result = a0 op a1".
5     * This could be a MIPS instruction or a function call.  (If the result
6     * comes back in a register other than a0, you can override "result".)
7     *
8     * If "chkzero" is set to 1, we perform a divide-by-zero check on
9     * vB (a1).  Useful for integer division and modulus.  Note that we
10     * *don't* check for (INT_MIN / -1) here, because the CPU handles it
11     * correctly.
12     *
13     * For: add-int/2addr, sub-int/2addr, mul-int/2addr, div-int/2addr,
14     *      rem-int/2addr, and-int/2addr, or-int/2addr, xor-int/2addr,
15     *      shl-int/2addr, shr-int/2addr, ushr-int/2addr
16     */
17    /* binop/2addr vA, vB */
18    ext     a2, rINST, 8, 4             # a2 <- A
19    ext     a3, rINST, 12, 4            # a3 <- B
20    GET_VREG a0, a2                     # a0 <- vA
21    GET_VREG a1, a3                     # a1 <- vB
22    .if $chkzero
23    beqz    a1, common_errDivideByZero  # is second operand zero?
24    .endif
25    FETCH_ADVANCE_INST 1                # advance rPC, load rINST
26    $preinstr                           # optional op
27    $instr                              # $result <- op, a0-a3 changed
28    GET_INST_OPCODE v0                  # extract opcode from rINST
29    SET_VREG $result, a2                # vA <- $result
30    GOTO_OPCODE v0                      # jump to next instruction
31