%default {"preinstr":"", "result":"r0", "chkzero":"0"} | |
/* | |
* Generic 32-bit "lit8" binary operation. Provide an "instr" line | |
* that specifies an instruction that performs "result = r0 op r1". | |
* This could be an ARM instruction or a function call. (If the result | |
* comes back in a register other than r0, you can override "result".) | |
* | |
* If "chkzero" is set to 1, we perform a divide-by-zero check on | |
* vCC (r1). Useful for integer division and modulus. | |
* | |
* For: add-int/lit8, rsub-int/lit8, mul-int/lit8, div-int/lit8, | |
* rem-int/lit8, and-int/lit8, or-int/lit8, xor-int/lit8, | |
* shl-int/lit8, shr-int/lit8, ushr-int/lit8 | |
*/ | |
/* binop/lit8 vAA, vBB, #+CC */ | |
FETCH_S(r3, 1) @ r3<- ssssCCBB (sign-extended for CC) | |
mov r9, rINST, lsr #8 @ r9<- AA | |
and r2, r3, #255 @ r2<- BB | |
GET_VREG(r0, r2) @ r0<- vBB | |
movs r1, r3, asr #8 @ r1<- ssssssCC (sign extended) | |
.if $chkzero | |
@cmp r1, #0 @ is second operand zero? | |
beq common_errDivideByZero | |
.endif | |
FETCH_ADVANCE_INST(2) @ advance rPC, load rINST | |
$preinstr @ optional op; may set condition codes | |
$instr @ $result<- op, r0-r3 changed | |
GET_INST_OPCODE(ip) @ extract opcode from rINST | |
SET_VREG($result, r9) @ vAA<- $result | |
GOTO_OPCODE(ip) @ jump to next instruction | |
/* 10-12 instructions */ | |