xref: /XiangShan/src/main/scala/xiangshan/backend/decode/DecodeUnit.scala (revision 708ceed4afe43fb0ea3a52407e46b2794c573634)
1/***************************************************************************************
2* Copyright (c) 2020-2021 Institute of Computing Technology, Chinese Academy of Sciences
3* Copyright (c) 2020-2021 Peng Cheng Laboratory
4*
5* XiangShan is licensed under Mulan PSL v2.
6* You can use this software according to the terms and conditions of the Mulan PSL v2.
7* You may obtain a copy of Mulan PSL v2 at:
8*          http://license.coscl.org.cn/MulanPSL2
9*
10* THIS SOFTWARE IS PROVIDED ON AN "AS IS" BASIS, WITHOUT WARRANTIES OF ANY KIND,
11* EITHER EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO NON-INFRINGEMENT,
12* MERCHANTABILITY OR FIT FOR A PARTICULAR PURPOSE.
13*
14* See the Mulan PSL v2 for more details.
15***************************************************************************************/
16
17package xiangshan.backend.decode
18
19import chipsalliance.rocketchip.config.Parameters
20import chisel3._
21import chisel3.util._
22import freechips.rocketchip.util.{UIntIsOneOf, uintToBitPat}
23import xiangshan._
24import utils._
25import xiangshan.backend._
26import xiangshan.backend.decode.BDecode.{N, Y}
27import xiangshan.backend.decode.Instructions._
28
29/**
30 * Abstract trait giving defaults and other relevant values to different Decode constants/
31 */
32abstract trait DecodeConstants {
33  def X = BitPat("b?")
34  def N = BitPat("b0")
35  def Y = BitPat("b1")
36
37  def decodeDefault: List[BitPat] = // illegal instruction
38    //   srcType(0)     srcType(1)     srcType(2)     fuType      fuOpType    rfWen
39    //   |            |            |            |           |           |  fpWen
40    //   |            |            |            |           |           |  |  isXSTrap
41    //   |            |            |            |           |           |  |  |  noSpecExec
42    //   |            |            |            |           |           |  |  |  |  blockBackward
43    //   |            |            |            |           |           |  |  |  |  |  flushPipe
44    //   |            |            |            |           |           |  |  |  |  |  |  isRVF
45    //   |            |            |            |           |           |  |  |  |  |  |  |  selImm
46    List(SrcType.DC, SrcType.DC, SrcType.DC, FuType.alu, ALUOpType.sll, N, N, N, N, N, N, N, SelImm.INVALID_INSTR) // Use SelImm to indicate invalid instr
47
48    val table: Array[(BitPat, List[BitPat])]
49}
50
51trait DecodeUnitConstants
52{
53  // abstract out instruction decode magic numbers
54  val RD_MSB  = 11
55  val RD_LSB  = 7
56  val RS1_MSB = 19
57  val RS1_LSB = 15
58  val RS2_MSB = 24
59  val RS2_LSB = 20
60  val RS3_MSB = 31
61  val RS3_LSB = 27
62}
63
64/**
65 * Decoded control signals
66 * See xiangshan/package.scala, xiangshan/backend/package.scala, Bundle.scala
67 */
68
69/**
70 * Decode constants for RV64
71 */
72object X64Decode extends DecodeConstants {
73  val table: Array[(BitPat, List[BitPat])] = Array(
74    LD      -> List(SrcType.reg, SrcType.imm, SrcType.DC, FuType.ldu, LSUOpType.ld, Y, N, N, N, N, N, N, SelImm.IMM_I),
75    LWU     -> List(SrcType.reg, SrcType.imm, SrcType.DC, FuType.ldu, LSUOpType.lwu, Y, N, N, N, N, N, N, SelImm.IMM_I),
76    SD      -> List(SrcType.reg, SrcType.reg, SrcType.DC, FuType.stu, LSUOpType.sd, N, N, N, N, N, N, N, SelImm.IMM_S),
77
78    SLLI    -> List(SrcType.reg, SrcType.imm, SrcType.DC, FuType.alu, ALUOpType.sll, Y, N, N, N, N, N, N, SelImm.IMM_I),
79    SRLI    -> List(SrcType.reg, SrcType.imm, SrcType.DC, FuType.alu, ALUOpType.srl, Y, N, N, N, N, N, N, SelImm.IMM_I),
80    SRAI    -> List(SrcType.reg, SrcType.imm, SrcType.DC, FuType.alu, ALUOpType.sra, Y, N, N, N, N, N, N, SelImm.IMM_I),
81
82    ADDIW   -> List(SrcType.reg, SrcType.imm, SrcType.DC, FuType.alu, ALUOpType.addw, Y, N, N, N, N, N, N, SelImm.IMM_I),
83    SLLIW   -> List(SrcType.reg, SrcType.imm, SrcType.DC, FuType.alu, ALUOpType.sllw, Y, N, N, N, N, N, N, SelImm.IMM_I),
84    SRAIW   -> List(SrcType.reg, SrcType.imm, SrcType.DC, FuType.alu, ALUOpType.sraw, Y, N, N, N, N, N, N, SelImm.IMM_I),
85    SRLIW   -> List(SrcType.reg, SrcType.imm, SrcType.DC, FuType.alu, ALUOpType.srlw, Y, N, N, N, N, N, N, SelImm.IMM_I),
86
87    ADDW    -> List(SrcType.reg, SrcType.reg, SrcType.DC, FuType.alu, ALUOpType.addw, Y, N, N, N, N, N, N, SelImm.IMM_X),
88    SUBW    -> List(SrcType.reg, SrcType.reg, SrcType.DC, FuType.alu, ALUOpType.subw, Y, N, N, N, N, N, N, SelImm.IMM_X),
89    SLLW    -> List(SrcType.reg, SrcType.reg, SrcType.DC, FuType.alu, ALUOpType.sllw, Y, N, N, N, N, N, N, SelImm.IMM_X),
90    SRAW    -> List(SrcType.reg, SrcType.reg, SrcType.DC, FuType.alu, ALUOpType.sraw, Y, N, N, N, N, N, N, SelImm.IMM_X),
91    SRLW    -> List(SrcType.reg, SrcType.reg, SrcType.DC, FuType.alu, ALUOpType.srlw, Y, N, N, N, N, N, N, SelImm.IMM_X),
92
93    RORW    -> List(SrcType.reg, SrcType.reg, SrcType.DC, FuType.alu, ALUOpType.rorw, Y, N, N, N, N, N, N, SelImm.IMM_X),
94    RORIW   -> List(SrcType.reg, SrcType.imm, SrcType.DC, FuType.alu, ALUOpType.rorw, Y, N, N, N, N, N, N, SelImm.IMM_I),
95    ROLW    -> List(SrcType.reg, SrcType.reg, SrcType.DC, FuType.alu, ALUOpType.rolw, Y, N, N, N, N, N, N, SelImm.IMM_X)
96  )
97}
98
99/**
100 * Overall Decode constants
101 */
102object XDecode extends DecodeConstants {
103  val table: Array[(BitPat, List[BitPat])] = Array(
104    LW      -> List(SrcType.reg, SrcType.imm, SrcType.DC, FuType.ldu, LSUOpType.lw, Y, N, N, N, N, N, N, SelImm.IMM_I),
105    LH      -> List(SrcType.reg, SrcType.imm, SrcType.DC, FuType.ldu, LSUOpType.lh, Y, N, N, N, N, N, N, SelImm.IMM_I),
106    LHU     -> List(SrcType.reg, SrcType.imm, SrcType.DC, FuType.ldu, LSUOpType.lhu, Y, N, N, N, N, N, N, SelImm.IMM_I),
107    LB      -> List(SrcType.reg, SrcType.imm, SrcType.DC, FuType.ldu, LSUOpType.lb, Y, N, N, N, N, N, N, SelImm.IMM_I),
108    LBU     -> List(SrcType.reg, SrcType.imm, SrcType.DC, FuType.ldu, LSUOpType.lbu, Y, N, N, N, N, N, N, SelImm.IMM_I),
109
110    SW      -> List(SrcType.reg, SrcType.reg, SrcType.DC, FuType.stu, LSUOpType.sw, N, N, N, N, N, N, N, SelImm.IMM_S),
111    SH      -> List(SrcType.reg, SrcType.reg, SrcType.DC, FuType.stu, LSUOpType.sh, N, N, N, N, N, N, N, SelImm.IMM_S),
112    SB      -> List(SrcType.reg, SrcType.reg, SrcType.DC, FuType.stu, LSUOpType.sb, N, N, N, N, N, N, N, SelImm.IMM_S),
113
114    LUI     -> List(SrcType.reg, SrcType.imm, SrcType.DC, FuType.alu, ALUOpType.add, Y, N, N, N, N, N, N, SelImm.IMM_U),
115
116    ADDI    -> List(SrcType.reg, SrcType.imm, SrcType.DC, FuType.alu, ALUOpType.add, Y, N, N, N, N, N, N, SelImm.IMM_I),
117    ANDI    -> List(SrcType.reg, SrcType.imm, SrcType.DC, FuType.alu, ALUOpType.and, Y, N, N, N, N, N, N, SelImm.IMM_I),
118    ORI     -> List(SrcType.reg, SrcType.imm, SrcType.DC, FuType.alu, ALUOpType.or, Y, N, N, N, N, N, N, SelImm.IMM_I),
119    XORI    -> List(SrcType.reg, SrcType.imm, SrcType.DC, FuType.alu, ALUOpType.xor, Y, N, N, N, N, N, N, SelImm.IMM_I),
120    SLTI    -> List(SrcType.reg, SrcType.imm, SrcType.DC, FuType.alu, ALUOpType.slt, Y, N, N, N, N, N, N, SelImm.IMM_I),
121    SLTIU   -> List(SrcType.reg, SrcType.imm, SrcType.DC, FuType.alu, ALUOpType.sltu, Y, N, N, N, N, N, N, SelImm.IMM_I),
122
123    SLL     -> List(SrcType.reg, SrcType.reg, SrcType.DC, FuType.alu, ALUOpType.sll, Y, N, N, N, N, N, N, SelImm.IMM_X),
124    ADD     -> List(SrcType.reg, SrcType.reg, SrcType.DC, FuType.alu, ALUOpType.add, Y, N, N, N, N, N, N, SelImm.IMM_X),
125    SUB     -> List(SrcType.reg, SrcType.reg, SrcType.DC, FuType.alu, ALUOpType.sub, Y, N, N, N, N, N, N, SelImm.IMM_X),
126    SLT     -> List(SrcType.reg, SrcType.reg, SrcType.DC, FuType.alu, ALUOpType.slt, Y, N, N, N, N, N, N, SelImm.IMM_X),
127    SLTU    -> List(SrcType.reg, SrcType.reg, SrcType.DC, FuType.alu, ALUOpType.sltu, Y, N, N, N, N, N, N, SelImm.IMM_X),
128    AND     -> List(SrcType.reg, SrcType.reg, SrcType.DC, FuType.alu, ALUOpType.and, Y, N, N, N, N, N, N, SelImm.IMM_X),
129    OR      -> List(SrcType.reg, SrcType.reg, SrcType.DC, FuType.alu, ALUOpType.or, Y, N, N, N, N, N, N, SelImm.IMM_X),
130    XOR     -> List(SrcType.reg, SrcType.reg, SrcType.DC, FuType.alu, ALUOpType.xor, Y, N, N, N, N, N, N, SelImm.IMM_X),
131    SRA     -> List(SrcType.reg, SrcType.reg, SrcType.DC, FuType.alu, ALUOpType.sra, Y, N, N, N, N, N, N, SelImm.IMM_X),
132    SRL     -> List(SrcType.reg, SrcType.reg, SrcType.DC, FuType.alu, ALUOpType.srl, Y, N, N, N, N, N, N, SelImm.IMM_X),
133
134    MUL     -> List(SrcType.reg, SrcType.reg, SrcType.DC, FuType.mul, MDUOpType.mul, Y, N, N, N, N, N, N, SelImm.IMM_X),
135    MULH    -> List(SrcType.reg, SrcType.reg, SrcType.DC, FuType.mul, MDUOpType.mulh, Y, N, N, N, N, N, N, SelImm.IMM_X),
136    MULHU   -> List(SrcType.reg, SrcType.reg, SrcType.DC, FuType.mul, MDUOpType.mulhu, Y, N, N, N, N, N, N, SelImm.IMM_X),
137    MULHSU  -> List(SrcType.reg, SrcType.reg, SrcType.DC, FuType.mul, MDUOpType.mulhsu, Y, N, N, N, N, N, N, SelImm.IMM_X),
138    MULW    -> List(SrcType.reg, SrcType.reg, SrcType.DC, FuType.mul, MDUOpType.mulw, Y, N, N, N, N, N, N, SelImm.IMM_X),
139
140    DIV     -> List(SrcType.reg, SrcType.reg, SrcType.DC, FuType.div, MDUOpType.div, Y, N, N, N, N, N, N, SelImm.IMM_X),
141    DIVU    -> List(SrcType.reg, SrcType.reg, SrcType.DC, FuType.div, MDUOpType.divu, Y, N, N, N, N, N, N, SelImm.IMM_X),
142    REM     -> List(SrcType.reg, SrcType.reg, SrcType.DC, FuType.div, MDUOpType.rem, Y, N, N, N, N, N, N, SelImm.IMM_X),
143    REMU    -> List(SrcType.reg, SrcType.reg, SrcType.DC, FuType.div, MDUOpType.remu, Y, N, N, N, N, N, N, SelImm.IMM_X),
144    DIVW    -> List(SrcType.reg, SrcType.reg, SrcType.DC, FuType.div, MDUOpType.divw, Y, N, N, N, N, N, N, SelImm.IMM_X),
145    DIVUW   -> List(SrcType.reg, SrcType.reg, SrcType.DC, FuType.div, MDUOpType.divuw, Y, N, N, N, N, N, N, SelImm.IMM_X),
146    REMW    -> List(SrcType.reg, SrcType.reg, SrcType.DC, FuType.div, MDUOpType.remw, Y, N, N, N, N, N, N, SelImm.IMM_X),
147    REMUW   -> List(SrcType.reg, SrcType.reg, SrcType.DC, FuType.div, MDUOpType.remuw, Y, N, N, N, N, N, N, SelImm.IMM_X),
148
149    AUIPC   -> List(SrcType.pc , SrcType.imm, SrcType.DC, FuType.jmp, JumpOpType.auipc, Y, N, N, N, N, N, N, SelImm.IMM_U),
150    JAL     -> List(SrcType.pc , SrcType.imm, SrcType.DC, FuType.jmp, JumpOpType.jal, Y, N, N, N, N, N, N, SelImm.IMM_UJ),
151    JALR    -> List(SrcType.reg, SrcType.imm, SrcType.DC, FuType.jmp, JumpOpType.jalr, Y, N, N, N, N, N, N, SelImm.IMM_I),
152    BEQ     -> List(SrcType.reg, SrcType.reg, SrcType.DC, FuType.alu, ALUOpType.beq, N, N, N, N, N, N, N, SelImm.IMM_SB),
153    BNE     -> List(SrcType.reg, SrcType.reg, SrcType.DC, FuType.alu, ALUOpType.bne, N, N, N, N, N, N, N, SelImm.IMM_SB),
154    BGE     -> List(SrcType.reg, SrcType.reg, SrcType.DC, FuType.alu, ALUOpType.bge, N, N, N, N, N, N, N, SelImm.IMM_SB),
155    BGEU    -> List(SrcType.reg, SrcType.reg, SrcType.DC, FuType.alu, ALUOpType.bgeu, N, N, N, N, N, N, N, SelImm.IMM_SB),
156    BLT     -> List(SrcType.reg, SrcType.reg, SrcType.DC, FuType.alu, ALUOpType.blt, N, N, N, N, N, N, N, SelImm.IMM_SB),
157    BLTU    -> List(SrcType.reg, SrcType.reg, SrcType.DC, FuType.alu, ALUOpType.bltu, N, N, N, N, N, N, N, SelImm.IMM_SB),
158
159    // I-type, the immediate12 holds the CSR register.
160    CSRRW   -> List(SrcType.reg, SrcType.imm, SrcType.DC, FuType.csr, CSROpType.wrt, Y, N, N, Y, Y, N, N, SelImm.IMM_I),
161    CSRRS   -> List(SrcType.reg, SrcType.imm, SrcType.DC, FuType.csr, CSROpType.set, Y, N, N, Y, Y, N, N, SelImm.IMM_I),
162    CSRRC   -> List(SrcType.reg, SrcType.imm, SrcType.DC, FuType.csr, CSROpType.clr, Y, N, N, Y, Y, N, N, SelImm.IMM_I),
163
164    CSRRWI  -> List(SrcType.reg, SrcType.imm, SrcType.DC, FuType.csr, CSROpType.wrti, Y, N, N, Y, Y, N, N, SelImm.IMM_Z),
165    CSRRSI  -> List(SrcType.reg, SrcType.imm, SrcType.DC, FuType.csr, CSROpType.seti, Y, N, N, Y, Y, N, N, SelImm.IMM_Z),
166    CSRRCI  -> List(SrcType.reg, SrcType.imm, SrcType.DC, FuType.csr, CSROpType.clri, Y, N, N, Y, Y, N, N, SelImm.IMM_Z),
167
168    SFENCE_VMA->List(SrcType.reg, SrcType.imm, SrcType.DC, FuType.fence, FenceOpType.sfence, N, N, N, Y, Y, Y, N, SelImm.IMM_X),
169    EBREAK  -> List(SrcType.reg, SrcType.imm, SrcType.DC, FuType.csr, CSROpType.jmp, Y, N, N, Y, Y, N, N, SelImm.IMM_I),
170    ECALL   -> List(SrcType.reg, SrcType.imm, SrcType.DC, FuType.csr, CSROpType.jmp, Y, N, N, Y, Y, N, N, SelImm.IMM_I),
171    SRET    -> List(SrcType.reg, SrcType.imm, SrcType.DC, FuType.csr, CSROpType.jmp, Y, N, N, Y, Y, N, N, SelImm.IMM_I),
172    MRET    -> List(SrcType.reg, SrcType.imm, SrcType.DC, FuType.csr, CSROpType.jmp, Y, N, N, Y, Y, N, N, SelImm.IMM_I),
173    DRET    -> List(SrcType.reg, SrcType.imm, SrcType.DC, FuType.csr, CSROpType.jmp, Y, N, N, Y, Y, N, N, SelImm.IMM_I),
174
175    WFI     -> List(SrcType.pc, SrcType.imm, SrcType.DC, FuType.alu, ALUOpType.sll, Y, N, N, N, N, N, N, SelImm.IMM_X),
176
177    FENCE_I -> List(SrcType.pc, SrcType.imm, SrcType.DC, FuType.fence, FenceOpType.fencei, N, N, N, Y, Y, Y, N, SelImm.IMM_X),
178    FENCE   -> List(SrcType.pc, SrcType.imm, SrcType.DC, FuType.fence, FenceOpType.fence, N, N, N, Y, Y, Y, N, SelImm.IMM_X),
179
180    // A-type
181    AMOADD_W-> List(SrcType.reg, SrcType.reg, SrcType.DC, FuType.mou, LSUOpType.amoadd_w, Y, N, N, Y, Y, N, N, SelImm.IMM_X),
182    AMOXOR_W-> List(SrcType.reg, SrcType.reg, SrcType.DC, FuType.mou, LSUOpType.amoxor_w, Y, N, N, Y, Y, N, N, SelImm.IMM_X),
183    AMOSWAP_W->List(SrcType.reg, SrcType.reg, SrcType.DC, FuType.mou, LSUOpType.amoswap_w, Y, N, N, Y, Y, N, N, SelImm.IMM_X),
184    AMOAND_W-> List(SrcType.reg, SrcType.reg, SrcType.DC, FuType.mou, LSUOpType.amoand_w, Y, N, N, Y, Y, N, N, SelImm.IMM_X),
185    AMOOR_W -> List(SrcType.reg, SrcType.reg, SrcType.DC, FuType.mou, LSUOpType.amoor_w, Y, N, N, Y, Y, N, N, SelImm.IMM_X),
186    AMOMIN_W-> List(SrcType.reg, SrcType.reg, SrcType.DC, FuType.mou, LSUOpType.amomin_w, Y, N, N, Y, Y, N, N, SelImm.IMM_X),
187    AMOMINU_W->List(SrcType.reg, SrcType.reg, SrcType.DC, FuType.mou, LSUOpType.amominu_w, Y, N, N, Y, Y, N, N, SelImm.IMM_X),
188    AMOMAX_W-> List(SrcType.reg, SrcType.reg, SrcType.DC, FuType.mou, LSUOpType.amomax_w, Y, N, N, Y, Y, N, N, SelImm.IMM_X),
189    AMOMAXU_W->List(SrcType.reg, SrcType.reg, SrcType.DC, FuType.mou, LSUOpType.amomaxu_w, Y, N, N, Y, Y, N, N, SelImm.IMM_X),
190
191    AMOADD_D-> List(SrcType.reg, SrcType.reg, SrcType.DC, FuType.mou, LSUOpType.amoadd_d, Y, N, N, Y, Y, N, N, SelImm.IMM_X),
192    AMOXOR_D-> List(SrcType.reg, SrcType.reg, SrcType.DC, FuType.mou, LSUOpType.amoxor_d, Y, N, N, Y, Y, N, N, SelImm.IMM_X),
193    AMOSWAP_D->List(SrcType.reg, SrcType.reg, SrcType.DC, FuType.mou, LSUOpType.amoswap_d, Y, N, N, Y, Y, N, N, SelImm.IMM_X),
194    AMOAND_D-> List(SrcType.reg, SrcType.reg, SrcType.DC, FuType.mou, LSUOpType.amoand_d, Y, N, N, Y, Y, N, N, SelImm.IMM_X),
195    AMOOR_D -> List(SrcType.reg, SrcType.reg, SrcType.DC, FuType.mou, LSUOpType.amoor_d, Y, N, N, Y, Y, N, N, SelImm.IMM_X),
196    AMOMIN_D-> List(SrcType.reg, SrcType.reg, SrcType.DC, FuType.mou, LSUOpType.amomin_d, Y, N, N, Y, Y, N, N, SelImm.IMM_X),
197    AMOMINU_D->List(SrcType.reg, SrcType.reg, SrcType.DC, FuType.mou, LSUOpType.amominu_d, Y, N, N, Y, Y, N, N, SelImm.IMM_X),
198    AMOMAX_D-> List(SrcType.reg, SrcType.reg, SrcType.DC, FuType.mou, LSUOpType.amomax_d, Y, N, N, Y, Y, N, N, SelImm.IMM_X),
199    AMOMAXU_D->List(SrcType.reg, SrcType.reg, SrcType.DC, FuType.mou, LSUOpType.amomaxu_d, Y, N, N, Y, Y, N, N, SelImm.IMM_X),
200
201    LR_W    -> List(SrcType.reg, SrcType.imm, SrcType.DC, FuType.mou, LSUOpType.lr_w, Y, N, N, Y, Y, N, N, SelImm.IMM_X),
202    LR_D    -> List(SrcType.reg, SrcType.imm, SrcType.DC, FuType.mou, LSUOpType.lr_d, Y, N, N, Y, Y, N, N, SelImm.IMM_X),
203    SC_W    -> List(SrcType.reg, SrcType.reg, SrcType.DC, FuType.mou, LSUOpType.sc_w, Y, N, N, Y, Y, N, N, SelImm.IMM_X),
204    SC_D    -> List(SrcType.reg, SrcType.reg, SrcType.DC, FuType.mou, LSUOpType.sc_d, Y, N, N, Y, Y, N, N, SelImm.IMM_X),
205
206    ANDN    -> List(SrcType.reg, SrcType.reg, SrcType.DC, FuType.alu, ALUOpType.andn, Y, N, N, N, N, N, N, SelImm.IMM_X),
207    ORN     -> List(SrcType.reg, SrcType.reg, SrcType.DC, FuType.alu, ALUOpType.orn, Y, N, N, N, N, N, N, SelImm.IMM_X),
208    XNOR    -> List(SrcType.reg, SrcType.reg, SrcType.DC, FuType.alu, ALUOpType.xnor, Y, N, N, N, N, N, N, SelImm.IMM_X),
209    ORC_B   -> List(SrcType.reg, SrcType.DC, SrcType.DC, FuType.alu, ALUOpType.orcb, Y, N, N, N, N, N, N, SelImm.IMM_X),
210
211    MIN     -> List(SrcType.reg, SrcType.reg, SrcType.DC, FuType.alu, ALUOpType.min, Y, N, N, N, N, N, N, SelImm.IMM_X),
212    MINU    -> List(SrcType.reg, SrcType.reg, SrcType.DC, FuType.alu, ALUOpType.minu, Y, N, N, N, N, N, N, SelImm.IMM_X),
213    MAX     -> List(SrcType.reg, SrcType.reg, SrcType.DC, FuType.alu, ALUOpType.max, Y, N, N, N, N, N, N, SelImm.IMM_X),
214    MAXU    -> List(SrcType.reg, SrcType.reg, SrcType.DC, FuType.alu, ALUOpType.maxu, Y, N, N, N, N, N, N, SelImm.IMM_X),
215
216    SEXT_B  -> List(SrcType.reg, SrcType.DC, SrcType.DC, FuType.alu, ALUOpType.sextb, Y, N, N, N, N, N, N, SelImm.IMM_X),
217    PACKH   -> List(SrcType.reg, SrcType.reg, SrcType.DC, FuType.alu, ALUOpType.packh, Y, N, N, N, N, N, N, SelImm.IMM_X),
218    SEXT_H  -> List(SrcType.reg, SrcType.DC, SrcType.DC, FuType.alu, ALUOpType.sexth, Y, N, N, N, N, N, N, SelImm.IMM_X),
219    PACKW   -> List(SrcType.reg, SrcType.reg, SrcType.DC, FuType.alu, ALUOpType.packw, Y, N, N, N, N, N, N, SelImm.IMM_X),
220    REVB    -> List(SrcType.reg, SrcType.DC, SrcType.DC, FuType.alu, ALUOpType.revb, Y, N, N, N, N, N, N, SelImm.IMM_X),
221    REV8    -> List(SrcType.reg, SrcType.DC, SrcType.DC, FuType.alu, ALUOpType.rev8, Y, N, N, N, N, N, N, SelImm.IMM_X),
222    PACK    -> List(SrcType.reg, SrcType.reg, SrcType.DC, FuType.alu, ALUOpType.pack, Y, N, N, N, N, N, N, SelImm.IMM_X),
223
224    BSET    -> List(SrcType.reg, SrcType.reg, SrcType.DC, FuType.alu, ALUOpType.bset, Y, N, N, N, N, N, N, SelImm.IMM_X),
225    BSETI   -> List(SrcType.reg, SrcType.imm, SrcType.DC, FuType.alu, ALUOpType.bset, Y, N, N, N, N, N, N, SelImm.IMM_I),
226    BCLR    -> List(SrcType.reg, SrcType.reg, SrcType.DC, FuType.alu, ALUOpType.bclr, Y, N, N, N, N, N, N, SelImm.IMM_X),
227    BCLRI   -> List(SrcType.reg, SrcType.imm, SrcType.DC, FuType.alu, ALUOpType.bclr, Y, N, N, N, N, N, N, SelImm.IMM_I),
228    BINV    -> List(SrcType.reg, SrcType.reg, SrcType.DC, FuType.alu, ALUOpType.binv, Y, N, N, N, N, N, N, SelImm.IMM_X),
229    BINVI   -> List(SrcType.reg, SrcType.imm, SrcType.DC, FuType.alu, ALUOpType.binv, Y, N, N, N, N, N, N, SelImm.IMM_I),
230    BEXT    -> List(SrcType.reg, SrcType.reg, SrcType.DC, FuType.alu, ALUOpType.bext, Y, N, N, N, N, N, N, SelImm.IMM_X),
231    BEXTI   -> List(SrcType.reg, SrcType.imm, SrcType.DC, FuType.alu, ALUOpType.bext, Y, N, N, N, N, N, N, SelImm.IMM_I),
232
233    ROR     -> List(SrcType.reg, SrcType.reg, SrcType.DC, FuType.alu, ALUOpType.ror, Y, N, N, N, N, N, N, SelImm.IMM_X),
234    RORI    -> List(SrcType.reg, SrcType.imm, SrcType.DC, FuType.alu, ALUOpType.ror, Y, N, N, N, N, N, N, SelImm.IMM_I),
235    ROL     -> List(SrcType.reg, SrcType.reg, SrcType.DC, FuType.alu, ALUOpType.rol, Y, N, N, N, N, N, N, SelImm.IMM_X),
236
237    SH1ADD  -> List(SrcType.reg, SrcType.reg, SrcType.DC, FuType.alu, ALUOpType.sh1add, Y, N, N, N, N, N, N, SelImm.IMM_X),
238    SH2ADD  -> List(SrcType.reg, SrcType.reg, SrcType.DC, FuType.alu, ALUOpType.sh2add, Y, N, N, N, N, N, N, SelImm.IMM_X),
239    SH3ADD  -> List(SrcType.reg, SrcType.reg, SrcType.DC, FuType.alu, ALUOpType.sh3add, Y, N, N, N, N, N, N, SelImm.IMM_X),
240    SH1ADDU_W   -> List(SrcType.reg, SrcType.reg, SrcType.DC, FuType.alu, ALUOpType.sh1adduw, Y, N, N, N, N, N, N, SelImm.IMM_X),
241    SH2ADDU_W   -> List(SrcType.reg, SrcType.reg, SrcType.DC, FuType.alu, ALUOpType.sh2adduw, Y, N, N, N, N, N, N, SelImm.IMM_X),
242    SH3ADDU_W   -> List(SrcType.reg, SrcType.reg, SrcType.DC, FuType.alu, ALUOpType.sh3adduw, Y, N, N, N, N, N, N, SelImm.IMM_X),
243    ADDU_W      -> List(SrcType.reg, SrcType.reg, SrcType.DC, FuType.alu, ALUOpType.adduw, Y, N, N, N, N, N, N, SelImm.IMM_X),
244    SLLIU_W     -> List(SrcType.reg, SrcType.imm, SrcType.DC, FuType.alu, ALUOpType.slliuw, Y, N, N, N, N, N, N, SelImm.IMM_I)
245  )
246}
247
248/**
249 * FP Decode constants
250 */
251object FDecode extends DecodeConstants{
252  val table: Array[(BitPat, List[BitPat])] = Array(
253
254  FLW     -> List(SrcType.reg, SrcType.imm, SrcType.DC, FuType.ldu, LSUOpType.lw, N, Y, N, N, N, N, Y, SelImm.IMM_I),
255  FLD     -> List(SrcType.reg, SrcType.imm, SrcType.DC, FuType.ldu, LSUOpType.ld, N, Y, N, N, N, N, N, SelImm.IMM_I),
256  FSW     -> List(SrcType.reg, SrcType.fp, SrcType.DC, FuType.stu, LSUOpType.sw, N, N, N, N, N, N, Y, SelImm.IMM_S),
257  FSD     -> List(SrcType.reg, SrcType.fp, SrcType.DC, FuType.stu, LSUOpType.sd, N, N, N, N, N, N, N, SelImm.IMM_S),
258
259  FCLASS_S-> List(SrcType.fp , SrcType.imm, SrcType.DC, FuType.fmisc, X, Y, N, N, N, N, N, Y, SelImm.IMM_X),
260  FCLASS_D-> List(SrcType.fp , SrcType.imm, SrcType.DC, FuType.fmisc, X, Y, N, N, N, N, N, N, SelImm.IMM_X),
261
262  FMV_D_X -> List(SrcType.reg, SrcType.imm, SrcType.DC, FuType.i2f, X, N, Y, N, N, N, N, N, SelImm.IMM_X),
263  FMV_X_D -> List(SrcType.fp , SrcType.imm, SrcType.DC, FuType.fmisc, X, Y, N, N, N, N, N, N, SelImm.IMM_X),
264  FMV_X_W -> List(SrcType.fp , SrcType.imm, SrcType.DC, FuType.fmisc, X, Y, N, N, N, N, N, Y, SelImm.IMM_X),
265  FMV_W_X -> List(SrcType.reg, SrcType.imm, SrcType.DC, FuType.i2f, X, N, Y, N, N, N, N, Y, SelImm.IMM_X),
266
267  FSGNJ_S -> List(SrcType.fp,  SrcType.fp, SrcType.DC, FuType.fmisc, X, N, Y, N, N, N, N, Y, SelImm.IMM_X),
268  FSGNJ_D -> List(SrcType.fp,  SrcType.fp, SrcType.DC, FuType.fmisc, X, N, Y, N, N, N, N, N, SelImm.IMM_X),
269  FSGNJX_S-> List(SrcType.fp,  SrcType.fp, SrcType.DC, FuType.fmisc, X, N, Y, N, N, N, N, Y, SelImm.IMM_X),
270  FSGNJX_D-> List(SrcType.fp,  SrcType.fp, SrcType.DC, FuType.fmisc, X, N, Y, N, N, N, N, N, SelImm.IMM_X),
271  FSGNJN_S-> List(SrcType.fp,  SrcType.fp, SrcType.DC, FuType.fmisc, X, N, Y, N, N, N, N, Y, SelImm.IMM_X),
272  FSGNJN_D-> List(SrcType.fp,  SrcType.fp, SrcType.DC, FuType.fmisc, X, N, Y, N, N, N, N, N, SelImm.IMM_X),
273
274  // FP to FP
275  FCVT_S_D-> List(SrcType.fp, SrcType.imm, SrcType.DC, FuType.fmisc, X, N, Y, N, N, N, N, Y, SelImm.IMM_X),
276  FCVT_D_S-> List(SrcType.fp, SrcType.imm, SrcType.DC, FuType.fmisc, X, N, Y, N, N, N, N, N, SelImm.IMM_X),
277
278  // Int to FP
279  FCVT_S_W-> List(SrcType.reg, SrcType.imm, SrcType.DC, FuType.i2f, X, N, Y, N, N, N, N, Y, SelImm.IMM_X),
280  FCVT_S_WU->List(SrcType.reg, SrcType.imm, SrcType.DC, FuType.i2f, X, N, Y, N, N, N, N, Y, SelImm.IMM_X),
281  FCVT_S_L-> List(SrcType.reg, SrcType.imm, SrcType.DC, FuType.i2f, X, N, Y, N, N, N, N, Y, SelImm.IMM_X),
282  FCVT_S_LU->List(SrcType.reg, SrcType.imm, SrcType.DC, FuType.i2f, X, N, Y, N, N, N, N, Y, SelImm.IMM_X),
283
284  FCVT_D_W-> List(SrcType.reg, SrcType.imm, SrcType.DC, FuType.i2f, X, N, Y, N, N, N, N, N, SelImm.IMM_X),
285  FCVT_D_WU->List(SrcType.reg, SrcType.imm, SrcType.DC, FuType.i2f, X, N, Y, N, N, N, N, N, SelImm.IMM_X),
286  FCVT_D_L-> List(SrcType.reg, SrcType.imm, SrcType.DC, FuType.i2f, X, N, Y, N, N, N, N, N, SelImm.IMM_X),
287  FCVT_D_LU->List(SrcType.reg, SrcType.imm, SrcType.DC, FuType.i2f, X, N, Y, N, N, N, N, N, SelImm.IMM_X),
288
289  // FP to Int
290  FCVT_W_S-> List(SrcType.fp , SrcType.imm, SrcType.DC, FuType.fmisc, X, Y, N, N, N, N, N, Y, SelImm.IMM_X),
291  FCVT_WU_S->List(SrcType.fp , SrcType.imm, SrcType.DC, FuType.fmisc, X, Y, N, N, N, N, N, Y, SelImm.IMM_X),
292  FCVT_L_S-> List(SrcType.fp , SrcType.imm, SrcType.DC, FuType.fmisc, X, Y, N, N, N, N, N, Y, SelImm.IMM_X),
293  FCVT_LU_S->List(SrcType.fp , SrcType.imm, SrcType.DC, FuType.fmisc, X, Y, N, N, N, N, N, Y, SelImm.IMM_X),
294
295  FCVT_W_D-> List(SrcType.fp , SrcType.imm, SrcType.DC, FuType.fmisc, X, Y, N, N, N, N, N, N, SelImm.IMM_X),
296  FCVT_WU_D->List(SrcType.fp , SrcType.imm, SrcType.DC, FuType.fmisc, X, Y, N, N, N, N, N, N, SelImm.IMM_X),
297  FCVT_L_D-> List(SrcType.fp , SrcType.imm, SrcType.DC, FuType.fmisc, X, Y, N, N, N, N, N, N, SelImm.IMM_X),
298  FCVT_LU_D->List(SrcType.fp , SrcType.imm, SrcType.DC, FuType.fmisc, X, Y, N, N, N, N, N, N, SelImm.IMM_X),
299
300  // "fp_single" is used for wb_data formatting (and debugging)
301  FEQ_S    ->List(SrcType.fp , SrcType.fp, SrcType.DC, FuType.fmisc, X, Y, N, N, N, N, N, Y, SelImm.IMM_X),
302  FLT_S    ->List(SrcType.fp , SrcType.fp, SrcType.DC, FuType.fmisc, X, Y, N, N, N, N, N, Y, SelImm.IMM_X),
303  FLE_S    ->List(SrcType.fp , SrcType.fp, SrcType.DC, FuType.fmisc, X, Y, N, N, N, N, N, Y, SelImm.IMM_X),
304
305  FEQ_D    ->List(SrcType.fp , SrcType.fp, SrcType.DC, FuType.fmisc, X, Y, N, N, N, N, N, N, SelImm.IMM_X),
306  FLT_D    ->List(SrcType.fp , SrcType.fp, SrcType.DC, FuType.fmisc, X, Y, N, N, N, N, N, N, SelImm.IMM_X),
307  FLE_D    ->List(SrcType.fp , SrcType.fp, SrcType.DC, FuType.fmisc, X, Y, N, N, N, N, N, N, SelImm.IMM_X),
308
309  FMIN_S   ->List(SrcType.fp,  SrcType.fp, SrcType.DC, FuType.fmisc, X, N, Y, N, N, N, N, Y, SelImm.IMM_X),
310  FMAX_S   ->List(SrcType.fp,  SrcType.fp, SrcType.DC, FuType.fmisc, X, N, Y, N, N, N, N, Y, SelImm.IMM_X),
311  FMIN_D   ->List(SrcType.fp,  SrcType.fp, SrcType.DC, FuType.fmisc, X, N, Y, N, N, N, N, N, SelImm.IMM_X),
312  FMAX_D   ->List(SrcType.fp,  SrcType.fp, SrcType.DC, FuType.fmisc, X, N, Y, N, N, N, N, N, SelImm.IMM_X),
313
314  FADD_S   ->List(SrcType.fp,  SrcType.fp, SrcType.DC, FuType.fmac, X, N, Y, N, N, N, N, Y, SelImm.IMM_X),
315  FSUB_S   ->List(SrcType.fp,  SrcType.fp, SrcType.DC, FuType.fmac, X, N, Y, N, N, N, N, Y, SelImm.IMM_X),
316  FMUL_S   ->List(SrcType.fp,  SrcType.fp, SrcType.DC, FuType.fmac, X, N, Y, N, N, N, N, Y, SelImm.IMM_X),
317  FADD_D   ->List(SrcType.fp,  SrcType.fp, SrcType.DC, FuType.fmac, X, N, Y, N, N, N, N, N, SelImm.IMM_X),
318  FSUB_D   ->List(SrcType.fp,  SrcType.fp, SrcType.DC, FuType.fmac, X, N, Y, N, N, N, N, N, SelImm.IMM_X),
319  FMUL_D   ->List(SrcType.fp,  SrcType.fp, SrcType.DC, FuType.fmac, X, N, Y, N, N, N, N, N, SelImm.IMM_X),
320
321  FMADD_S  ->List(SrcType.fp,  SrcType.fp, SrcType.fp, FuType.fmac, X, N, Y, N, N, N, N, Y, SelImm.IMM_X),
322  FMSUB_S  ->List(SrcType.fp,  SrcType.fp, SrcType.fp, FuType.fmac, X, N, Y, N, N, N, N, Y, SelImm.IMM_X),
323  FNMADD_S ->List(SrcType.fp,  SrcType.fp, SrcType.fp, FuType.fmac, X, N, Y, N, N, N, N, Y, SelImm.IMM_X),
324  FNMSUB_S ->List(SrcType.fp,  SrcType.fp, SrcType.fp, FuType.fmac, X, N, Y, N, N, N, N, Y, SelImm.IMM_X),
325  FMADD_D  ->List(SrcType.fp,  SrcType.fp, SrcType.fp, FuType.fmac, X, N, Y, N, N, N, N, N, SelImm.IMM_X),
326  FMSUB_D  ->List(SrcType.fp,  SrcType.fp, SrcType.fp, FuType.fmac, X, N, Y, N, N, N, N, N, SelImm.IMM_X),
327  FNMADD_D ->List(SrcType.fp,  SrcType.fp, SrcType.fp, FuType.fmac, X, N, Y, N, N, N, N, N, SelImm.IMM_X),
328  FNMSUB_D ->List(SrcType.fp,  SrcType.fp, SrcType.fp, FuType.fmac, X, N, Y, N, N, N, N, N, SelImm.IMM_X)
329  )
330}
331
332/**
333  * Bit Manipulation Decode
334  */
335object BDecode extends DecodeConstants{
336  val table: Array[(BitPat, List[BitPat])] = Array(
337    // Basic bit manipulation
338    CLZ     -> List(SrcType.reg, SrcType.DC, SrcType.DC, FuType.bmu, BMUOpType.clz, Y, N, N, N, N, N, N, SelImm.IMM_X),
339    CTZ     -> List(SrcType.reg, SrcType.DC, SrcType.DC, FuType.bmu, BMUOpType.ctz, Y, N, N, N, N, N, N, SelImm.IMM_X),
340    CPOP    -> List(SrcType.reg, SrcType.DC, SrcType.DC, FuType.bmu, BMUOpType.cpop, Y, N, N, N, N, N, N, SelImm.IMM_X),
341    XPERM_B -> List(SrcType.reg, SrcType.reg, SrcType.DC, FuType.bmu, BMUOpType.xpermb, Y, N, N, N, N, N, N, SelImm.IMM_X),
342    XPERM_N -> List(SrcType.reg, SrcType.reg, SrcType.DC, FuType.bmu, BMUOpType.xpermn, Y, N, N, N, N, N, N, SelImm.IMM_X),
343
344    CLZW    -> List(SrcType.reg, SrcType.DC, SrcType.DC, FuType.bmu, BMUOpType.clzw, Y, N, N, N, N, N, N, SelImm.IMM_X),
345    CTZW    -> List(SrcType.reg, SrcType.DC, SrcType.DC, FuType.bmu, BMUOpType.ctzw, Y, N, N, N, N, N, N, SelImm.IMM_X),
346    CPOPW   -> List(SrcType.reg, SrcType.DC, SrcType.DC, FuType.bmu, BMUOpType.cpopw, Y, N, N, N, N, N, N, SelImm.IMM_X),
347
348    CLMUL   -> List(SrcType.reg, SrcType.reg, SrcType.DC, FuType.bmu, BMUOpType.clmul, Y, N, N, N, N, N, N, SelImm.IMM_X),
349    CLMULH  -> List(SrcType.reg, SrcType.reg, SrcType.DC, FuType.bmu, BMUOpType.clmulh, Y, N, N, N, N, N, N, SelImm.IMM_X),
350    CLMULR  -> List(SrcType.reg, SrcType.reg, SrcType.DC, FuType.bmu, BMUOpType.clmulr, Y, N, N, N, N, N, N, SelImm.IMM_X)
351  )
352}
353
354/**
355 * FP Divide SquareRoot Constants
356 */
357object FDivSqrtDecode extends DecodeConstants {
358  val table: Array[(BitPat, List[BitPat])] = Array(
359  FDIV_S    ->List(SrcType.fp,  SrcType.fp, SrcType.DC, FuType.fmisc, X, N, Y, N, N, N, N, Y, SelImm.IMM_X),
360  FDIV_D    ->List(SrcType.fp,  SrcType.fp, SrcType.DC, FuType.fmisc, X, N, Y, N, N, N, N, N, SelImm.IMM_X),
361  FSQRT_S   ->List(SrcType.fp,  SrcType.imm, SrcType.DC, FuType.fmisc, X, N, Y, N, N, N, N, Y, SelImm.IMM_X),
362  FSQRT_D   ->List(SrcType.fp,  SrcType.imm, SrcType.DC, FuType.fmisc, X, N, Y, N, N, N, N, N, SelImm.IMM_X)
363  )
364}
365
366/**
367 * XiangShan Trap Decode constants
368 */
369object XSTrapDecode extends DecodeConstants {
370  // calculate as ADDI => addi zero, a0, 0
371  // replace rs '?????' with '01010'(a0) in decode stage
372  def lsrc1 = "b01010".U // $a0
373  val table: Array[(BitPat, List[BitPat])] = Array(
374    TRAP    -> List(SrcType.reg, SrcType.imm, SrcType.DC, FuType.alu, ALUOpType.add, Y, N, Y, Y, Y, N, N, SelImm.IMM_I)
375  )
376}
377
378//object Imm32Gen {
379//  def apply(sel: UInt, inst: UInt) = {
380//    val sign = Mux(sel === SelImm.IMM_Z, 0.S, inst(31).asSInt)
381//    val b30_20 = Mux(sel === SelImm.IMM_U, inst(30,20).asSInt, sign)
382//    val b19_12 = Mux(sel =/= SelImm.IMM_U && sel =/= SelImm.IMM_UJ, sign, inst(19,12).asSInt)
383//    val b11 = Mux(sel === SelImm.IMM_U || sel === SelImm.IMM_Z, 0.S,
384//              Mux(sel === SelImm.IMM_UJ, inst(20).asSInt,
385//              Mux(sel === SelImm.IMM_SB, inst(7).asSInt, sign)))
386//    val b10_5 = Mux(sel === SelImm.IMM_U || sel === SelImm.IMM_Z, 0.U(1.W), inst(30,25))
387//    val b4_1 = Mux(sel === SelImm.IMM_U, 0.U(1.W),
388//               Mux(sel === SelImm.IMM_S || sel === SelImm.IMM_SB, inst(11,8),
389//               Mux(sel === SelImm.IMM_Z, inst(19,16), inst(24,21))))
390//    val b0 = Mux(sel === SelImm.IMM_S, inst(7),
391//             Mux(sel === SelImm.IMM_I, inst(20),
392//             Mux(sel === SelImm.IMM_Z, inst(15), 0.U(1.W))))
393//
394//    Cat(sign, b30_20, b19_12, b11, b10_5, b4_1, b0)
395//  }
396//}
397
398abstract class Imm(val len: Int) extends Bundle {
399  def toImm32(minBits: UInt): UInt = do_toImm32(minBits(len - 1, 0))
400  def do_toImm32(minBits: UInt): UInt
401  def minBitsFromInstr(instr: UInt): UInt
402}
403
404case class Imm_I() extends Imm(12) {
405  override def do_toImm32(minBits: UInt): UInt = SignExt(minBits, 32)
406
407  override def minBitsFromInstr(instr: UInt): UInt =
408    Cat(instr(31, 20))
409}
410
411case class Imm_S() extends Imm(12) {
412  override def do_toImm32(minBits: UInt): UInt = SignExt(minBits, 32)
413
414  override def minBitsFromInstr(instr: UInt): UInt =
415    Cat(instr(31, 25), instr(11, 7))
416}
417
418case class Imm_B() extends Imm(12) {
419  override def do_toImm32(minBits: UInt): UInt = SignExt(Cat(minBits, 0.U(1.W)), 32)
420
421  override def minBitsFromInstr(instr: UInt): UInt =
422    Cat(instr(31), instr(7), instr(30, 25), instr(11, 8))
423}
424
425case class Imm_U() extends Imm(20){
426  override def do_toImm32(minBits: UInt): UInt = Cat(minBits, 0.U(12.W))
427
428  override def minBitsFromInstr(instr: UInt): UInt = {
429    instr(31, 12)
430  }
431}
432
433case class Imm_J() extends Imm(20){
434  override def do_toImm32(minBits: UInt): UInt = SignExt(Cat(minBits, 0.U(1.W)), 32)
435
436  override def minBitsFromInstr(instr: UInt): UInt = {
437    Cat(instr(31), instr(19, 12), instr(20), instr(30, 25), instr(24, 21))
438  }
439}
440
441case class Imm_Z() extends Imm(12 + 5){
442  override def do_toImm32(minBits: UInt): UInt = minBits
443
444  override def minBitsFromInstr(instr: UInt): UInt = {
445    Cat(instr(19, 15), instr(31, 20))
446  }
447}
448
449case class Imm_B6() extends Imm(6){
450  override def do_toImm32(minBits: UInt): UInt = ZeroExt(minBits, 32)
451
452  override def minBitsFromInstr(instr: UInt): UInt = {
453    instr(25, 20)
454  }
455}
456
457object ImmUnion {
458  val I = Imm_I()
459  val S = Imm_S()
460  val B = Imm_B()
461  val U = Imm_U()
462  val J = Imm_J()
463  val Z = Imm_Z()
464  val B6 = Imm_B6()
465  val imms = Seq(I, S, B, U, J, Z, B6)
466  val maxLen = imms.maxBy(_.len).len
467  val immSelMap = Seq(
468    SelImm.IMM_I,
469    SelImm.IMM_S,
470    SelImm.IMM_SB,
471    SelImm.IMM_U,
472    SelImm.IMM_UJ,
473    SelImm.IMM_Z,
474    SelImm.IMM_B6
475  ).zip(imms)
476  println(s"ImmUnion max len: $maxLen")
477}
478
479
480/**
481 * IO bundle for the Decode unit
482 */
483class DecodeUnitIO(implicit p: Parameters) extends XSBundle {
484  val enq = new Bundle { val ctrl_flow = Input(new CtrlFlow) }
485  val deq = new Bundle { val cf_ctrl = Output(new CfCtrl) }
486}
487
488/**
489 * Decode unit that takes in a single CtrlFlow and generates a CfCtrl.
490 */
491class DecodeUnit(implicit p: Parameters) extends XSModule with DecodeUnitConstants {
492  val io = IO(new DecodeUnitIO)
493
494  val ctrl_flow = Wire(new CtrlFlow) // input with RVC Expanded
495  val cf_ctrl = Wire(new CfCtrl)
496
497  ctrl_flow := io.enq.ctrl_flow
498
499  val decode_table = XDecode.table ++ FDecode.table ++ FDivSqrtDecode.table ++ X64Decode.table ++ XSTrapDecode.table ++ BDecode.table
500
501  // output
502  cf_ctrl.cf := ctrl_flow
503  val cs = Wire(new CtrlSignals()).decode(ctrl_flow.instr, decode_table)
504  cs.singleStep := false.B
505  cs.replayInst := false.B
506
507  cs.isFused := 0.U
508
509  val fpDecoder = Module(new FPDecoder)
510  fpDecoder.io.instr := ctrl_flow.instr
511  cs.fpu := fpDecoder.io.fpCtrl
512
513  val isMove = BitPat("b000000000000_?????_000_?????_0010011") === ctrl_flow.instr
514  cs.isMove := isMove
515
516  // read src1~3 location
517  cs.lsrc(0) := Mux(ctrl_flow.instr === LUI, 0.U,ctrl_flow.instr(RS1_MSB,RS1_LSB))
518  cs.lsrc(1) := ctrl_flow.instr(RS2_MSB,RS2_LSB)
519  cs.lsrc(2) := ctrl_flow.instr(RS3_MSB,RS3_LSB)
520  // read dest location
521  cs.ldest := Mux((cs.fpWen || cs.rfWen) && !(isMove && ctrl_flow.instr(RS1_MSB,RS1_LSB) === ctrl_flow.instr(RD_MSB,RD_LSB)), ctrl_flow.instr(RD_MSB,RD_LSB), 0.U)
522
523  // fill in exception vector
524  cf_ctrl.cf.exceptionVec := io.enq.ctrl_flow.exceptionVec
525  cf_ctrl.cf.exceptionVec(illegalInstr) := cs.selImm === SelImm.INVALID_INSTR
526
527  // fix frflags
528  //                           fflags    zero csrrs rd    csr
529  val isFrflags = BitPat("b000000000001_00000_010_?????_1110011") === ctrl_flow.instr
530  when (cs.fuType === FuType.csr && isFrflags) {
531    cs.blockBackward := false.B
532  }
533
534  // fix isXSTrap
535  when (cs.isXSTrap) {
536    cs.lsrc(0) := XSTrapDecode.lsrc1
537  }
538
539  cs.imm := LookupTree(cs.selImm, ImmUnion.immSelMap.map(
540    x => {
541      val minBits = x._2.minBitsFromInstr(ctrl_flow.instr)
542      require(minBits.getWidth == x._2.len)
543      x._1 -> minBits
544    }
545  ))
546
547  cf_ctrl.ctrl := cs
548
549  // TODO: do we still need this?
550  // fix ret and call
551//  when (cs.fuType === FuType.jmp) {
552//    def isLink(reg: UInt) = (reg === 1.U || reg === 5.U)
553//    when (isLink(cs.ldest) && cs.fuOpType === JumpOpType.jal) { cf_ctrl.ctrl.fuOpType := JumpOpType.call }
554//    when (cs.fuOpType === JumpOpType.jalr) {
555//      when (isLink(cs.lsrc(0))) { cf_ctrl.ctrl.fuOpType := JumpOpType.ret  }
556//      when (isLink(cs.ldest)) { cf_ctrl.ctrl.fuOpType := JumpOpType.call }
557//    }
558//  }
559
560  io.deq.cf_ctrl := cf_ctrl
561
562  //-------------------------------------------------------------
563  // Debug Info
564  XSDebug("in:  instr=%x pc=%x excepVec=%b intrVec=%b crossPageIPFFix=%d\n",
565    io.enq.ctrl_flow.instr, io.enq.ctrl_flow.pc, io.enq.ctrl_flow.exceptionVec.asUInt,
566    io.enq.ctrl_flow.intrVec.asUInt, io.enq.ctrl_flow.crossPageIPFFix)
567  XSDebug("out: srcType(0)=%b srcType(1)=%b srcType(2)=%b lsrc(0)=%d lsrc(1)=%d lsrc(2)=%d ldest=%d fuType=%b fuOpType=%b\n",
568    io.deq.cf_ctrl.ctrl.srcType(0), io.deq.cf_ctrl.ctrl.srcType(1), io.deq.cf_ctrl.ctrl.srcType(2),
569    io.deq.cf_ctrl.ctrl.lsrc(0), io.deq.cf_ctrl.ctrl.lsrc(1), io.deq.cf_ctrl.ctrl.lsrc(2),
570    io.deq.cf_ctrl.ctrl.ldest, io.deq.cf_ctrl.ctrl.fuType, io.deq.cf_ctrl.ctrl.fuOpType)
571  XSDebug("out: rfWen=%d fpWen=%d isXSTrap=%d noSpecExec=%d isBlocked=%d flushPipe=%d isRVF=%d imm=%x\n",
572    io.deq.cf_ctrl.ctrl.rfWen, io.deq.cf_ctrl.ctrl.fpWen, io.deq.cf_ctrl.ctrl.isXSTrap,
573    io.deq.cf_ctrl.ctrl.noSpecExec, io.deq.cf_ctrl.ctrl.blockBackward, io.deq.cf_ctrl.ctrl.flushPipe,
574    io.deq.cf_ctrl.ctrl.isRVF, io.deq.cf_ctrl.ctrl.imm)
575  XSDebug("out: excepVec=%b intrVec=%b\n",
576    io.deq.cf_ctrl.cf.exceptionVec.asUInt, io.deq.cf_ctrl.cf.intrVec.asUInt)
577}
578