gem5/src/arch/riscv/isa/decoder.isa

333 lines
9.7 KiB
C++

// -*- mode:c++ -*-
// Copyright (c) 2015 RISC-V Foundation
// Copyright (c) 2016 The University of Virginia
// All rights reserved.
//
// Redistribution and use in source and binary forms, with or without
// modification, are permitted provided that the following conditions are
// met: redistributions of source code must retain the above copyright
// notice, this list of conditions and the following disclaimer;
// redistributions in binary form must reproduce the above copyright
// notice, this list of conditions and the following disclaimer in the
// documentation and/or other materials provided with the distribution;
// neither the name of the copyright holders nor the names of its
// contributors may be used to endorse or promote products derived from
// this software without specific prior written permission.
//
// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
//
// Authors: Alec Roelke
////////////////////////////////////////////////////////////////////
//
// The RISC-V ISA decoder
//
decode OPCODE default Unknown::unknown() {
0x03: decode FUNCT3 {
format Load {
0x0: lb({{
Rd_sd = Mem_sb;
}});
0x1: lh({{
Rd_sd = Mem_sh;
}});
0x2: lw({{
Rd_sd = Mem_sw;
}});
0x3: ld({{
Rd_sd = Mem_sd;
}});
0x4: lbu({{
Rd = Mem_ub;
}});
0x5: lhu({{
Rd = Mem_uh;
}});
0x6: lwu({{
Rd = Mem_uw;
}});
}
}
0x0f: decode FUNCT3 {
format IOp {
0x0: fence({{
}}, IsNonSpeculative, IsMemBarrier, No_OpClass);
0x1: fence_i({{
}}, IsNonSpeculative, IsSerializeAfter, No_OpClass);
}
}
0x13: decode FUNCT3 {
format IOp {
0x0: addi({{
Rd_sd = Rs1_sd + imm;
}});
0x1: slli({{
Rd = Rs1 << SHAMT6;
}});
0x2: slti({{
Rd = (Rs1_sd < imm) ? 1 : 0;
}});
0x3: sltiu({{
Rd = (Rs1 < (uint64_t)imm) ? 1 : 0;
}});
0x4: xori({{
Rd = Rs1 ^ (uint64_t)imm;
}});
0x5: decode SRTYPE {
0x0: srli({{
Rd = Rs1 >> SHAMT6;
}});
0x1: srai({{
Rd_sd = Rs1_sd >> SHAMT6;
}});
}
0x6: ori({{
Rd = Rs1 | (uint64_t)imm;
}});
0x7: andi({{
Rd = Rs1 & (uint64_t)imm;
}});
}
}
0x17: UOp::auipc({{
Rd = PC + imm;
}});
0x1b: decode FUNCT3 {
format IOp {
0x0: addiw({{
Rd_sd = (int32_t)Rs1 + (int32_t)imm;
}});
0x1: slliw({{
Rd_sd = Rs1_sw << SHAMT5;
}});
0x5: decode SRTYPE {
0x0: srliw({{
Rd = Rs1_uw >> SHAMT5;
}});
0x1: sraiw({{
Rd_sd = Rs1_sw >> SHAMT5;
}});
}
}
}
0x23: decode FUNCT3 {
format Store {
0x0: sb({{
Mem_ub = Rs2_ub;
}});
0x1: sh({{
Mem_uh = Rs2_uh;
}});
0x2: sw({{
Mem_uw = Rs2_uw;
}});
0x3: sd({{
Mem_ud = Rs2_ud;
}});
}
}
0x33: decode FUNCT3 {
format ROp {
0x0: decode FUNCT7 {
0x0: add({{
Rd = Rs1_sd + Rs2_sd;
}});
0x20: sub({{
Rd = Rs1_sd - Rs2_sd;
}});
}
0x1: decode FUNCT7 {
0x0: sll({{
Rd = Rs1 << Rs2<5:0>;
}});
}
0x2: decode FUNCT7 {
0x0: slt({{
Rd = (Rs1_sd < Rs2_sd) ? 1 : 0;
}});
}
0x3: decode FUNCT7 {
0x0: sltu({{
Rd = (Rs1 < Rs2) ? 1 : 0;
}});
}
0x4: decode FUNCT7 {
0x0: xor({{
Rd = Rs1 ^ Rs2;
}});
}
0x5: decode FUNCT7 {
0x0: srl({{
Rd = Rs1 >> Rs2<5:0>;
}});
0x20: sra({{
Rd_sd = Rs1_sd >> Rs2<5:0>;
}});
}
0x6: decode FUNCT7 {
0x0: or({{
Rd = Rs1 | Rs2;
}});
}
0x7: decode FUNCT7 {
0x0: and({{
Rd = Rs1 & Rs2;
}});
}
}
}
0x37: UOp::lui({{
Rd = (uint64_t)imm;
}});
0x3b: decode FUNCT3 {
format ROp {
0x0: decode FUNCT7 {
0x0: addw({{
Rd_sd = Rs1_sw + Rs2_sw;
}});
0x20: subw({{
Rd_sd = Rs1_sw - Rs2_sw;
}});
}
0x1: sllw({{
Rd_sd = Rs1_sw << Rs2<4:0>;
}});
0x5: decode FUNCT7 {
0x0: srlw({{
Rd_uw = Rs1_uw >> Rs2<4:0>;
}});
0x20: sraw({{
Rd_sd = Rs1_sw >> Rs2<4:0>;
}});
}
}
}
0x63: decode FUNCT3 {
format SBOp {
0x0: beq({{
if (Rs1 == Rs2) {
NPC = PC + imm;
} else {
NPC = NPC;
}
}}, IsDirectControl, IsCondControl);
0x1: bne({{
if (Rs1 != Rs2) {
NPC = PC + imm;
} else {
NPC = NPC;
}
}}, IsDirectControl, IsCondControl);
0x4: blt({{
if (Rs1_sd < Rs2_sd) {
NPC = PC + imm;
} else {
NPC = NPC;
}
}}, IsDirectControl, IsCondControl);
0x5: bge({{
if (Rs1_sd >= Rs2_sd) {
NPC = PC + imm;
} else {
NPC = NPC;
}
}}, IsDirectControl, IsCondControl);
0x6: bltu({{
if (Rs1 < Rs2) {
NPC = PC + imm;
} else {
NPC = NPC;
}
}}, IsDirectControl, IsCondControl);
0x7: bgeu({{
if (Rs1 >= Rs2) {
NPC = PC + imm;
} else {
NPC = NPC;
}
}}, IsDirectControl, IsCondControl);
}
}
0x67: decode FUNCT3 {
0x0: Jump::jalr({{
Rd = NPC;
NPC = (imm + Rs1) & (~0x1);
}}, IsIndirectControl, IsUncondControl, IsCall);
}
0x6f: UJOp::jal({{
Rd = NPC;
NPC = PC + imm;
}}, IsDirectControl, IsUncondControl, IsCall);
0x73: decode FUNCT3 {
format IOp {
0x0: decode FUNCT12 {
0x0: ecall({{
fault = std::make_shared<SyscallFault>();
}}, IsSerializeAfter, IsNonSpeculative, IsSyscall, No_OpClass);
0x1: ebreak({{
fault = std::make_shared<BreakpointFault>();
}}, IsSerializeAfter, IsNonSpeculative, No_OpClass);
0x100: eret({{
fault = std::make_shared<UnimplementedFault>("eret");
}}, No_OpClass);
}
0x1: csrrw({{
Rd = xc->readMiscReg(FUNCT12);
xc->setMiscReg(FUNCT12, Rs1);
}}, IsNonSpeculative, No_OpClass);
0x2: csrrs({{
Rd = xc->readMiscReg(FUNCT12);
if (Rs1 != 0) {
xc->setMiscReg(FUNCT12, Rd | Rs1);
}
}}, IsNonSpeculative, No_OpClass);
0x3: csrrc({{
Rd = xc->readMiscReg(FUNCT12);
if (Rs1 != 0) {
xc->setMiscReg(FUNCT12, Rd & ~Rs1);
}
}}, IsNonSpeculative, No_OpClass);
0x5: csrrwi({{
Rd = xc->readMiscReg(FUNCT12);
xc->setMiscReg(FUNCT12, ZIMM);
}}, IsNonSpeculative, No_OpClass);
0x6: csrrsi({{
Rd = xc->readMiscReg(FUNCT12);
if (ZIMM != 0) {
xc->setMiscReg(FUNCT12, Rd | ZIMM);
}
}}, IsNonSpeculative, No_OpClass);
0x7: csrrci({{
Rd = xc->readMiscReg(FUNCT12);
if (ZIMM != 0) {
xc->setMiscReg(FUNCT12, Rd & ~ZIMM);
}
}}, IsNonSpeculative, No_OpClass);
}
}
}