Raghu Gandham | a8b91c5 | 2012-05-02 14:27:16 -0700 | [diff] [blame] | 1 | %default {"preinstr":"", "result":"a0", "chkzero":"0"} |
| 2 | /* |
| 3 | * Generic 32-bit "lit8" binary operation. Provide an "instr" line |
| 4 | * that specifies an instruction that performs "result = a0 op a1". |
| 5 | * This could be an 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 | * vCC (a1). Useful for integer division and modulus. |
| 10 | * |
| 11 | * For: add-int/lit8, rsub-int/lit8, mul-int/lit8, div-int/lit8, |
| 12 | * rem-int/lit8, and-int/lit8, or-int/lit8, xor-int/lit8, |
| 13 | * shl-int/lit8, shr-int/lit8, ushr-int/lit8 |
| 14 | */ |
| 15 | # binop/lit8 vAA, vBB, /* +CC */ |
| 16 | FETCH_S(a3, 1) # a3 <- ssssCCBB (sign-extended for CC) |
| 17 | GET_OPA(rOBJ) # rOBJ <- AA |
| 18 | and a2, a3, 255 # a2 <- BB |
| 19 | GET_VREG(a0, a2) # a0 <- vBB |
| 20 | sra a1, a3, 8 # a1 <- ssssssCC (sign extended) |
| 21 | .if $chkzero |
| 22 | # is second operand zero? |
| 23 | beqz a1, common_errDivideByZero |
| 24 | .endif |
| 25 | FETCH_ADVANCE_INST(2) # advance rPC, load rINST |
| 26 | |
| 27 | $preinstr # optional op |
| 28 | $instr # $result <- op, a0-a3 changed |
| 29 | GET_INST_OPCODE(t0) # extract opcode from rINST |
| 30 | SET_VREG_GOTO($result, rOBJ, t0) # vAA <- $result |
| 31 | /* 10-12 instructions */ |
| 32 | |