Files
wasmtime/meta/isa/riscv/encodings.py
Jakob Stoklund Olesen 1da15a10d7 Add RISC-V arithmetic w/immediate operand encodings.
Add new instruction predicates to support the 'I' encoding recipe: IsSignedInt,
IsUnsignedInt used to test that an immediate operand is in the allowed range.
2016-08-24 08:53:44 -07:00

45 lines
1.6 KiB
Python

"""
RISC-V Encodings.
"""
from __future__ import absolute_import
from cretonne import base
from .defs import RV32, RV64
from .recipes import OPIMM, OPIMM32, OP, OP32, R, Rshamt, I
# Basic arithmetic binary instructions are encoded in an R-type instruction.
for inst, inst_imm, f3, f7 in [
(base.iadd, base.iadd_imm, 0b000, 0b0000000),
(base.isub, None, 0b000, 0b0100000),
(base.bxor, base.bxor_imm, 0b100, 0b0000000),
(base.bor, base.bor_imm, 0b110, 0b0000000),
(base.band, base.band_imm, 0b111, 0b0000000)
]:
RV32.enc(inst.i32, R, OP(f3, f7))
RV64.enc(inst.i64, R, OP(f3, f7))
# Immediate versions for add/xor/or/and.
if inst_imm:
RV32.enc(inst_imm.i32, I, OPIMM(f3))
RV64.enc(inst_imm.i64, I, OPIMM(f3))
# There are no andiw/oriw/xoriw variations.
RV64.enc(base.iadd_imm.i32, I, OPIMM32(0b000))
# Dynamic shifts have the same masking semantics as the cton base instructions.
for inst, inst_imm, f3, f7 in [
(base.ishl, base.ishl_imm, 0b001, 0b0000000),
(base.ushr, base.ushr_imm, 0b101, 0b0000000),
(base.sshr, base.sshr_imm, 0b101, 0b0100000),
]:
RV32.enc(inst.i32.i32, R, OP(f3, f7))
RV64.enc(inst.i64.i64, R, OP(f3, f7))
RV64.enc(inst.i32.i32, R, OP32(f3, f7))
# Allow i32 shift amounts in 64-bit shifts.
RV64.enc(inst.i64.i32, R, OP(f3, f7))
RV64.enc(inst.i32.i64, R, OP32(f3, f7))
# Immediate shifts.
RV32.enc(inst_imm.i32, Rshamt, OPIMM(f3, f7))
RV64.enc(inst_imm.i64, Rshamt, OPIMM(f3, f7))
RV64.enc(inst_imm.i32, Rshamt, OPIMM32(f3, f7))