xref: /XiangShan/src/main/scala/xiangshan/backend/decode/DecodeUnit.scala (revision dc597826530cb6803c2396d6ab0e5eb176b732e0)
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
210    MIN     -> List(SrcType.reg, SrcType.reg, SrcType.DC, FuType.alu, ALUOpType.min, Y, N, N, N, N, N, N, SelImm.IMM_X),
211    MINU    -> List(SrcType.reg, SrcType.reg, SrcType.DC, FuType.alu, ALUOpType.minu, Y, N, N, N, N, N, N, SelImm.IMM_X),
212    MAX     -> List(SrcType.reg, SrcType.reg, SrcType.DC, FuType.alu, ALUOpType.max, Y, N, N, N, N, N, N, SelImm.IMM_X),
213    MAXU    -> List(SrcType.reg, SrcType.reg, SrcType.DC, FuType.alu, ALUOpType.maxu, Y, N, N, N, N, N, N, SelImm.IMM_X),
214
215    SEXT_B  -> List(SrcType.reg, SrcType.DC, SrcType.DC, FuType.alu, ALUOpType.sext_b, Y, N, N, N, N, N, N, SelImm.IMM_X),
216    SEXT_H  -> List(SrcType.reg, SrcType.DC, SrcType.DC, FuType.alu, ALUOpType.sext_h, Y, N, N, N, N, N, N, SelImm.IMM_X),
217    ZEXT_H  -> List(SrcType.reg, SrcType.DC, SrcType.DC, FuType.alu, ALUOpType.zext_h, Y, N, N, N, N, N, N, SelImm.IMM_X),
218
219    ORC_B   -> List(SrcType.reg, SrcType.DC, SrcType.DC, FuType.alu, ALUOpType.orc_b, Y, N, N, N, N, N, N, SelImm.IMM_X),
220    REV8    -> List(SrcType.reg, SrcType.DC, SrcType.DC, FuType.alu, ALUOpType.rev8, Y, N, N, N, N, N, N, SelImm.IMM_X),
221
222    BSET    -> List(SrcType.reg, SrcType.reg, SrcType.DC, FuType.alu, ALUOpType.bset, Y, N, N, N, N, N, N, SelImm.IMM_X),
223    BSETI   -> List(SrcType.reg, SrcType.imm, SrcType.DC, FuType.alu, ALUOpType.bset, Y, N, N, N, N, N, N, SelImm.IMM_I),
224    BCLR    -> List(SrcType.reg, SrcType.reg, SrcType.DC, FuType.alu, ALUOpType.bclr, Y, N, N, N, N, N, N, SelImm.IMM_X),
225    BCLRI   -> List(SrcType.reg, SrcType.imm, SrcType.DC, FuType.alu, ALUOpType.bclr, Y, N, N, N, N, N, N, SelImm.IMM_I),
226    BINV    -> List(SrcType.reg, SrcType.reg, SrcType.DC, FuType.alu, ALUOpType.binv, Y, N, N, N, N, N, N, SelImm.IMM_X),
227    BINVI   -> List(SrcType.reg, SrcType.imm, SrcType.DC, FuType.alu, ALUOpType.binv, Y, N, N, N, N, N, N, SelImm.IMM_I),
228    BEXT    -> List(SrcType.reg, SrcType.reg, SrcType.DC, FuType.alu, ALUOpType.bext, Y, N, N, N, N, N, N, SelImm.IMM_X),
229    BEXTI   -> List(SrcType.reg, SrcType.imm, SrcType.DC, FuType.alu, ALUOpType.bext, Y, N, N, N, N, N, N, SelImm.IMM_I),
230
231    ROR     -> List(SrcType.reg, SrcType.reg, SrcType.DC, FuType.alu, ALUOpType.ror, Y, N, N, N, N, N, N, SelImm.IMM_X),
232    RORI    -> List(SrcType.reg, SrcType.imm, SrcType.DC, FuType.alu, ALUOpType.ror, Y, N, N, N, N, N, N, SelImm.IMM_I),
233    ROL     -> List(SrcType.reg, SrcType.reg, SrcType.DC, FuType.alu, ALUOpType.rol, Y, N, N, N, N, N, N, SelImm.IMM_X),
234
235    SH1ADD  -> List(SrcType.reg, SrcType.reg, SrcType.DC, FuType.alu, ALUOpType.sh1add, Y, N, N, N, N, N, N, SelImm.IMM_X),
236    SH2ADD  -> List(SrcType.reg, SrcType.reg, SrcType.DC, FuType.alu, ALUOpType.sh2add, Y, N, N, N, N, N, N, SelImm.IMM_X),
237    SH3ADD  -> List(SrcType.reg, SrcType.reg, SrcType.DC, FuType.alu, ALUOpType.sh3add, Y, N, N, N, N, N, N, SelImm.IMM_X),
238    SH1ADDU_W   -> List(SrcType.reg, SrcType.reg, SrcType.DC, FuType.alu, ALUOpType.sh1add_uw, Y, N, N, N, N, N, N, SelImm.IMM_X),
239    SH2ADDU_W   -> List(SrcType.reg, SrcType.reg, SrcType.DC, FuType.alu, ALUOpType.sh2add_uw, Y, N, N, N, N, N, N, SelImm.IMM_X),
240    SH3ADDU_W   -> List(SrcType.reg, SrcType.reg, SrcType.DC, FuType.alu, ALUOpType.sh3add_uw, Y, N, N, N, N, N, N, SelImm.IMM_X),
241    ADDU_W      -> List(SrcType.reg, SrcType.reg, SrcType.DC, FuType.alu, ALUOpType.add_uw, Y, N, N, N, N, N, N, SelImm.IMM_X),
242    SLLIU_W     -> List(SrcType.reg, SrcType.imm, SrcType.DC, FuType.alu, ALUOpType.slli_uw, Y, N, N, N, N, N, N, SelImm.IMM_I),
243  )
244}
245
246/**
247 * FP Decode constants
248 */
249object FDecode extends DecodeConstants{
250  val table: Array[(BitPat, List[BitPat])] = Array(
251
252  FLW     -> List(SrcType.reg, SrcType.imm, SrcType.DC, FuType.ldu, LSUOpType.lw, N, Y, N, N, N, N, Y, SelImm.IMM_I),
253  FLD     -> List(SrcType.reg, SrcType.imm, SrcType.DC, FuType.ldu, LSUOpType.ld, N, Y, N, N, N, N, N, SelImm.IMM_I),
254  FSW     -> List(SrcType.reg, SrcType.fp, SrcType.DC, FuType.stu, LSUOpType.sw, N, N, N, N, N, N, Y, SelImm.IMM_S),
255  FSD     -> List(SrcType.reg, SrcType.fp, SrcType.DC, FuType.stu, LSUOpType.sd, N, N, N, N, N, N, N, SelImm.IMM_S),
256
257  FCLASS_S-> List(SrcType.fp , SrcType.imm, SrcType.DC, FuType.fmisc, X, Y, N, N, N, N, N, Y, SelImm.IMM_X),
258  FCLASS_D-> List(SrcType.fp , SrcType.imm, SrcType.DC, FuType.fmisc, X, Y, N, N, N, N, N, N, SelImm.IMM_X),
259
260  FMV_D_X -> List(SrcType.reg, SrcType.imm, SrcType.DC, FuType.i2f, X, N, Y, N, N, N, N, N, SelImm.IMM_X),
261  FMV_X_D -> List(SrcType.fp , SrcType.imm, SrcType.DC, FuType.fmisc, X, Y, N, N, N, N, N, N, SelImm.IMM_X),
262  FMV_X_W -> List(SrcType.fp , SrcType.imm, SrcType.DC, FuType.fmisc, X, Y, N, N, N, N, N, Y, SelImm.IMM_X),
263  FMV_W_X -> List(SrcType.reg, SrcType.imm, SrcType.DC, FuType.i2f, X, N, Y, N, N, N, N, Y, SelImm.IMM_X),
264
265  FSGNJ_S -> List(SrcType.fp,  SrcType.fp, SrcType.DC, FuType.fmisc, X, N, Y, N, N, N, N, Y, SelImm.IMM_X),
266  FSGNJ_D -> List(SrcType.fp,  SrcType.fp, SrcType.DC, FuType.fmisc, X, N, Y, N, N, N, N, N, SelImm.IMM_X),
267  FSGNJX_S-> List(SrcType.fp,  SrcType.fp, SrcType.DC, FuType.fmisc, X, N, Y, N, N, N, N, Y, SelImm.IMM_X),
268  FSGNJX_D-> List(SrcType.fp,  SrcType.fp, SrcType.DC, FuType.fmisc, X, N, Y, N, N, N, N, N, SelImm.IMM_X),
269  FSGNJN_S-> List(SrcType.fp,  SrcType.fp, SrcType.DC, FuType.fmisc, X, N, Y, N, N, N, N, Y, SelImm.IMM_X),
270  FSGNJN_D-> List(SrcType.fp,  SrcType.fp, SrcType.DC, FuType.fmisc, X, N, Y, N, N, N, N, N, SelImm.IMM_X),
271
272  // FP to FP
273  FCVT_S_D-> List(SrcType.fp, SrcType.imm, SrcType.DC, FuType.fmisc, X, N, Y, N, N, N, N, Y, SelImm.IMM_X),
274  FCVT_D_S-> List(SrcType.fp, SrcType.imm, SrcType.DC, FuType.fmisc, X, N, Y, N, N, N, N, N, SelImm.IMM_X),
275
276  // Int to FP
277  FCVT_S_W-> List(SrcType.reg, SrcType.imm, SrcType.DC, FuType.i2f, X, N, Y, N, N, N, N, Y, SelImm.IMM_X),
278  FCVT_S_WU->List(SrcType.reg, SrcType.imm, SrcType.DC, FuType.i2f, X, N, Y, N, N, N, N, Y, SelImm.IMM_X),
279  FCVT_S_L-> List(SrcType.reg, SrcType.imm, SrcType.DC, FuType.i2f, X, N, Y, N, N, N, N, Y, SelImm.IMM_X),
280  FCVT_S_LU->List(SrcType.reg, SrcType.imm, SrcType.DC, FuType.i2f, X, N, Y, N, N, N, N, Y, SelImm.IMM_X),
281
282  FCVT_D_W-> List(SrcType.reg, SrcType.imm, SrcType.DC, FuType.i2f, X, N, Y, N, N, N, N, N, SelImm.IMM_X),
283  FCVT_D_WU->List(SrcType.reg, SrcType.imm, SrcType.DC, FuType.i2f, X, N, Y, N, N, N, N, N, SelImm.IMM_X),
284  FCVT_D_L-> List(SrcType.reg, SrcType.imm, SrcType.DC, FuType.i2f, X, N, Y, N, N, N, N, N, SelImm.IMM_X),
285  FCVT_D_LU->List(SrcType.reg, SrcType.imm, SrcType.DC, FuType.i2f, X, N, Y, N, N, N, N, N, SelImm.IMM_X),
286
287  // FP to Int
288  FCVT_W_S-> List(SrcType.fp , SrcType.imm, SrcType.DC, FuType.fmisc, X, Y, N, N, N, N, N, Y, SelImm.IMM_X),
289  FCVT_WU_S->List(SrcType.fp , SrcType.imm, SrcType.DC, FuType.fmisc, X, Y, N, N, N, N, N, Y, SelImm.IMM_X),
290  FCVT_L_S-> List(SrcType.fp , SrcType.imm, SrcType.DC, FuType.fmisc, X, Y, N, N, N, N, N, Y, SelImm.IMM_X),
291  FCVT_LU_S->List(SrcType.fp , SrcType.imm, SrcType.DC, FuType.fmisc, X, Y, N, N, N, N, N, Y, SelImm.IMM_X),
292
293  FCVT_W_D-> List(SrcType.fp , SrcType.imm, SrcType.DC, FuType.fmisc, X, Y, N, N, N, N, N, N, SelImm.IMM_X),
294  FCVT_WU_D->List(SrcType.fp , SrcType.imm, SrcType.DC, FuType.fmisc, X, Y, N, N, N, N, N, N, SelImm.IMM_X),
295  FCVT_L_D-> List(SrcType.fp , SrcType.imm, SrcType.DC, FuType.fmisc, X, Y, N, N, N, N, N, N, SelImm.IMM_X),
296  FCVT_LU_D->List(SrcType.fp , SrcType.imm, SrcType.DC, FuType.fmisc, X, Y, N, N, N, N, N, N, SelImm.IMM_X),
297
298  // "fp_single" is used for wb_data formatting (and debugging)
299  FEQ_S    ->List(SrcType.fp , SrcType.fp, SrcType.DC, FuType.fmisc, X, Y, N, N, N, N, N, Y, SelImm.IMM_X),
300  FLT_S    ->List(SrcType.fp , SrcType.fp, SrcType.DC, FuType.fmisc, X, Y, N, N, N, N, N, Y, SelImm.IMM_X),
301  FLE_S    ->List(SrcType.fp , SrcType.fp, SrcType.DC, FuType.fmisc, X, Y, N, N, N, N, N, Y, SelImm.IMM_X),
302
303  FEQ_D    ->List(SrcType.fp , SrcType.fp, SrcType.DC, FuType.fmisc, X, Y, N, N, N, N, N, N, SelImm.IMM_X),
304  FLT_D    ->List(SrcType.fp , SrcType.fp, SrcType.DC, FuType.fmisc, X, Y, N, N, N, N, N, N, SelImm.IMM_X),
305  FLE_D    ->List(SrcType.fp , SrcType.fp, SrcType.DC, FuType.fmisc, X, Y, N, N, N, N, N, N, SelImm.IMM_X),
306
307  FMIN_S   ->List(SrcType.fp,  SrcType.fp, SrcType.DC, FuType.fmisc, X, N, Y, N, N, N, N, Y, SelImm.IMM_X),
308  FMAX_S   ->List(SrcType.fp,  SrcType.fp, SrcType.DC, FuType.fmisc, X, N, Y, N, N, N, N, Y, SelImm.IMM_X),
309  FMIN_D   ->List(SrcType.fp,  SrcType.fp, SrcType.DC, FuType.fmisc, X, N, Y, N, N, N, N, N, SelImm.IMM_X),
310  FMAX_D   ->List(SrcType.fp,  SrcType.fp, SrcType.DC, FuType.fmisc, X, N, Y, N, N, N, N, N, SelImm.IMM_X),
311
312  FADD_S   ->List(SrcType.fp,  SrcType.fp, SrcType.DC, FuType.fmac, X, N, Y, N, N, N, N, Y, SelImm.IMM_X),
313  FSUB_S   ->List(SrcType.fp,  SrcType.fp, SrcType.DC, FuType.fmac, X, N, Y, N, N, N, N, Y, SelImm.IMM_X),
314  FMUL_S   ->List(SrcType.fp,  SrcType.fp, SrcType.DC, FuType.fmac, X, N, Y, N, N, N, N, Y, SelImm.IMM_X),
315  FADD_D   ->List(SrcType.fp,  SrcType.fp, SrcType.DC, FuType.fmac, X, N, Y, N, N, N, N, N, SelImm.IMM_X),
316  FSUB_D   ->List(SrcType.fp,  SrcType.fp, SrcType.DC, FuType.fmac, X, N, Y, N, N, N, N, N, SelImm.IMM_X),
317  FMUL_D   ->List(SrcType.fp,  SrcType.fp, SrcType.DC, FuType.fmac, X, N, Y, N, N, N, N, N, SelImm.IMM_X),
318
319  FMADD_S  ->List(SrcType.fp,  SrcType.fp, SrcType.fp, FuType.fmac, X, N, Y, N, N, N, N, Y, SelImm.IMM_X),
320  FMSUB_S  ->List(SrcType.fp,  SrcType.fp, SrcType.fp, FuType.fmac, X, N, Y, N, N, N, N, Y, SelImm.IMM_X),
321  FNMADD_S ->List(SrcType.fp,  SrcType.fp, SrcType.fp, FuType.fmac, X, N, Y, N, N, N, N, Y, SelImm.IMM_X),
322  FNMSUB_S ->List(SrcType.fp,  SrcType.fp, SrcType.fp, FuType.fmac, X, N, Y, N, N, N, N, Y, SelImm.IMM_X),
323  FMADD_D  ->List(SrcType.fp,  SrcType.fp, SrcType.fp, FuType.fmac, X, N, Y, N, N, N, N, N, SelImm.IMM_X),
324  FMSUB_D  ->List(SrcType.fp,  SrcType.fp, SrcType.fp, FuType.fmac, X, N, Y, N, N, N, N, N, SelImm.IMM_X),
325  FNMADD_D ->List(SrcType.fp,  SrcType.fp, SrcType.fp, FuType.fmac, X, N, Y, N, N, N, N, N, SelImm.IMM_X),
326  FNMSUB_D ->List(SrcType.fp,  SrcType.fp, SrcType.fp, FuType.fmac, X, N, Y, N, N, N, N, N, SelImm.IMM_X)
327  )
328}
329
330/**
331  * Bit Manipulation Decode
332  */
333object BDecode extends DecodeConstants{
334  val table: Array[(BitPat, List[BitPat])] = Array(
335    // Basic bit manipulation
336    CLZ     -> List(SrcType.reg, SrcType.DC, SrcType.DC, FuType.bmu, BMUOpType.clz, Y, N, N, N, N, N, N, SelImm.IMM_X),
337    CTZ     -> List(SrcType.reg, SrcType.DC, SrcType.DC, FuType.bmu, BMUOpType.ctz, Y, N, N, N, N, N, N, SelImm.IMM_X),
338    CPOP    -> List(SrcType.reg, SrcType.DC, SrcType.DC, FuType.bmu, BMUOpType.cpop, Y, N, N, N, N, N, N, SelImm.IMM_X),
339
340    CLZW    -> List(SrcType.reg, SrcType.DC, SrcType.DC, FuType.bmu, BMUOpType.clzw, Y, N, N, N, N, N, N, SelImm.IMM_X),
341    CTZW    -> List(SrcType.reg, SrcType.DC, SrcType.DC, FuType.bmu, BMUOpType.ctzw, Y, N, N, N, N, N, N, SelImm.IMM_X),
342    CPOPW   -> List(SrcType.reg, SrcType.DC, SrcType.DC, FuType.bmu, BMUOpType.cpopw, Y, N, N, N, N, N, N, SelImm.IMM_X),
343
344    CLMUL   -> List(SrcType.reg, SrcType.reg, SrcType.DC, FuType.bmu, BMUOpType.clmul, Y, N, N, N, N, N, N, SelImm.IMM_X),
345    CLMULH  -> List(SrcType.reg, SrcType.reg, SrcType.DC, FuType.bmu, BMUOpType.clmulh, Y, N, N, N, N, N, N, SelImm.IMM_X),
346    CLMULR  -> List(SrcType.reg, SrcType.reg, SrcType.DC, FuType.bmu, BMUOpType.clmulr, Y, N, N, N, N, N, N, SelImm.IMM_X)
347  )
348}
349
350/**
351 * FP Divide SquareRoot Constants
352 */
353object FDivSqrtDecode extends DecodeConstants {
354  val table: Array[(BitPat, List[BitPat])] = Array(
355  FDIV_S    ->List(SrcType.fp,  SrcType.fp, SrcType.DC, FuType.fmisc, X, N, Y, N, N, N, N, Y, SelImm.IMM_X),
356  FDIV_D    ->List(SrcType.fp,  SrcType.fp, SrcType.DC, FuType.fmisc, X, N, Y, N, N, N, N, N, SelImm.IMM_X),
357  FSQRT_S   ->List(SrcType.fp,  SrcType.imm, SrcType.DC, FuType.fmisc, X, N, Y, N, N, N, N, Y, SelImm.IMM_X),
358  FSQRT_D   ->List(SrcType.fp,  SrcType.imm, SrcType.DC, FuType.fmisc, X, N, Y, N, N, N, N, N, SelImm.IMM_X)
359  )
360}
361
362/**
363 * XiangShan Trap Decode constants
364 */
365object XSTrapDecode extends DecodeConstants {
366  // calculate as ADDI => addi zero, a0, 0
367  // replace rs '?????' with '01010'(a0) in decode stage
368  def lsrc1 = "b01010".U // $a0
369  val table: Array[(BitPat, List[BitPat])] = Array(
370    TRAP    -> List(SrcType.reg, SrcType.imm, SrcType.DC, FuType.alu, ALUOpType.add, Y, N, Y, Y, Y, N, N, SelImm.IMM_I)
371  )
372}
373
374//object Imm32Gen {
375//  def apply(sel: UInt, inst: UInt) = {
376//    val sign = Mux(sel === SelImm.IMM_Z, 0.S, inst(31).asSInt)
377//    val b30_20 = Mux(sel === SelImm.IMM_U, inst(30,20).asSInt, sign)
378//    val b19_12 = Mux(sel =/= SelImm.IMM_U && sel =/= SelImm.IMM_UJ, sign, inst(19,12).asSInt)
379//    val b11 = Mux(sel === SelImm.IMM_U || sel === SelImm.IMM_Z, 0.S,
380//              Mux(sel === SelImm.IMM_UJ, inst(20).asSInt,
381//              Mux(sel === SelImm.IMM_SB, inst(7).asSInt, sign)))
382//    val b10_5 = Mux(sel === SelImm.IMM_U || sel === SelImm.IMM_Z, 0.U(1.W), inst(30,25))
383//    val b4_1 = Mux(sel === SelImm.IMM_U, 0.U(1.W),
384//               Mux(sel === SelImm.IMM_S || sel === SelImm.IMM_SB, inst(11,8),
385//               Mux(sel === SelImm.IMM_Z, inst(19,16), inst(24,21))))
386//    val b0 = Mux(sel === SelImm.IMM_S, inst(7),
387//             Mux(sel === SelImm.IMM_I, inst(20),
388//             Mux(sel === SelImm.IMM_Z, inst(15), 0.U(1.W))))
389//
390//    Cat(sign, b30_20, b19_12, b11, b10_5, b4_1, b0)
391//  }
392//}
393
394abstract class Imm(val len: Int) extends Bundle {
395  def toImm32(minBits: UInt): UInt = do_toImm32(minBits(len - 1, 0))
396  def do_toImm32(minBits: UInt): UInt
397  def minBitsFromInstr(instr: UInt): UInt
398}
399
400case class Imm_I() extends Imm(12) {
401  override def do_toImm32(minBits: UInt): UInt = SignExt(minBits, 32)
402
403  override def minBitsFromInstr(instr: UInt): UInt =
404    Cat(instr(31, 20))
405}
406
407case class Imm_S() extends Imm(12) {
408  override def do_toImm32(minBits: UInt): UInt = SignExt(minBits, 32)
409
410  override def minBitsFromInstr(instr: UInt): UInt =
411    Cat(instr(31, 25), instr(11, 7))
412}
413
414case class Imm_B() extends Imm(12) {
415  override def do_toImm32(minBits: UInt): UInt = SignExt(Cat(minBits, 0.U(1.W)), 32)
416
417  override def minBitsFromInstr(instr: UInt): UInt =
418    Cat(instr(31), instr(7), instr(30, 25), instr(11, 8))
419}
420
421case class Imm_U() extends Imm(20){
422  override def do_toImm32(minBits: UInt): UInt = Cat(minBits, 0.U(12.W))
423
424  override def minBitsFromInstr(instr: UInt): UInt = {
425    instr(31, 12)
426  }
427}
428
429case class Imm_J() extends Imm(20){
430  override def do_toImm32(minBits: UInt): UInt = SignExt(Cat(minBits, 0.U(1.W)), 32)
431
432  override def minBitsFromInstr(instr: UInt): UInt = {
433    Cat(instr(31), instr(19, 12), instr(20), instr(30, 25), instr(24, 21))
434  }
435}
436
437case class Imm_Z() extends Imm(12 + 5){
438  override def do_toImm32(minBits: UInt): UInt = minBits
439
440  override def minBitsFromInstr(instr: UInt): UInt = {
441    Cat(instr(19, 15), instr(31, 20))
442  }
443}
444
445case class Imm_B6() extends Imm(6){
446  override def do_toImm32(minBits: UInt): UInt = ZeroExt(minBits, 32)
447
448  override def minBitsFromInstr(instr: UInt): UInt = {
449    instr(25, 20)
450  }
451}
452
453object ImmUnion {
454  val I = Imm_I()
455  val S = Imm_S()
456  val B = Imm_B()
457  val U = Imm_U()
458  val J = Imm_J()
459  val Z = Imm_Z()
460  val B6 = Imm_B6()
461  val imms = Seq(I, S, B, U, J, Z, B6)
462  val maxLen = imms.maxBy(_.len).len
463  val immSelMap = Seq(
464    SelImm.IMM_I,
465    SelImm.IMM_S,
466    SelImm.IMM_SB,
467    SelImm.IMM_U,
468    SelImm.IMM_UJ,
469    SelImm.IMM_Z,
470    SelImm.IMM_B6
471  ).zip(imms)
472  println(s"ImmUnion max len: $maxLen")
473}
474
475
476/**
477 * IO bundle for the Decode unit
478 */
479class DecodeUnitIO(implicit p: Parameters) extends XSBundle {
480  val enq = new Bundle { val ctrl_flow = Input(new CtrlFlow) }
481  val deq = new Bundle { val cf_ctrl = Output(new CfCtrl) }
482}
483
484/**
485 * Decode unit that takes in a single CtrlFlow and generates a CfCtrl.
486 */
487class DecodeUnit(implicit p: Parameters) extends XSModule with DecodeUnitConstants {
488  val io = IO(new DecodeUnitIO)
489
490  val ctrl_flow = Wire(new CtrlFlow) // input with RVC Expanded
491  val cf_ctrl = Wire(new CfCtrl)
492
493  ctrl_flow := io.enq.ctrl_flow
494
495  var decode_table = XDecode.table ++ FDecode.table ++ FDivSqrtDecode.table ++ X64Decode.table ++ XSTrapDecode.table ++ BDecode.table
496
497  // output
498  cf_ctrl.cf := ctrl_flow
499  val cs = Wire(new CtrlSignals()).decode(ctrl_flow.instr, decode_table)
500  cs.singleStep := false.B
501
502  val fpDecoder = Module(new FPDecoder)
503  fpDecoder.io.instr := ctrl_flow.instr
504  cs.fpu := fpDecoder.io.fpCtrl
505
506  // read src1~3 location
507  cs.lsrc(0) := Mux(ctrl_flow.instr === LUI, 0.U,ctrl_flow.instr(RS1_MSB,RS1_LSB))
508  cs.lsrc(1) := ctrl_flow.instr(RS2_MSB,RS2_LSB)
509  cs.lsrc(2) := ctrl_flow.instr(RS3_MSB,RS3_LSB)
510  // read dest location
511  cs.ldest := Mux(cs.fpWen || cs.rfWen, ctrl_flow.instr(RD_MSB,RD_LSB), 0.U)
512
513  // fill in exception vector
514  cf_ctrl.cf.exceptionVec := io.enq.ctrl_flow.exceptionVec
515  cf_ctrl.cf.exceptionVec(illegalInstr) := cs.selImm === SelImm.INVALID_INSTR
516
517  // fix frflags
518  //                           fflags    zero csrrs rd    csr
519  val isFrflags = BitPat("b000000000001_00000_010_?????_1110011") === ctrl_flow.instr
520  when (cs.fuType === FuType.csr && isFrflags) {
521    cs.blockBackward := false.B
522  }
523
524  // fix isXSTrap
525  when (cs.isXSTrap) {
526    cs.lsrc(0) := XSTrapDecode.lsrc1
527  }
528
529  cs.imm := LookupTree(cs.selImm, ImmUnion.immSelMap.map(
530    x => {
531      val minBits = x._2.minBitsFromInstr(ctrl_flow.instr)
532      require(minBits.getWidth == x._2.len)
533      x._1 -> minBits
534    }
535  ))
536
537  cs.isMove := BitPat("b000000000000_?????_000_?????_0010011") === ctrl_flow.instr &&
538    cs.lsrc(0) =/= 0.U && cs.ldest =/= 0.U &&
539    cs.lsrc(0) =/= cs.ldest /* TODO these special Move instructions can be optimized */
540
541  cf_ctrl.ctrl := cs
542
543  // TODO: do we still need this?
544  // fix ret and call
545//  when (cs.fuType === FuType.jmp) {
546//    def isLink(reg: UInt) = (reg === 1.U || reg === 5.U)
547//    when (isLink(cs.ldest) && cs.fuOpType === JumpOpType.jal) { cf_ctrl.ctrl.fuOpType := JumpOpType.call }
548//    when (cs.fuOpType === JumpOpType.jalr) {
549//      when (isLink(cs.lsrc(0))) { cf_ctrl.ctrl.fuOpType := JumpOpType.ret  }
550//      when (isLink(cs.ldest)) { cf_ctrl.ctrl.fuOpType := JumpOpType.call }
551//    }
552//  }
553
554  io.deq.cf_ctrl := cf_ctrl
555
556  //-------------------------------------------------------------
557  // Debug Info
558  XSDebug("in:  instr=%x pc=%x excepVec=%b intrVec=%b crossPageIPFFix=%d\n",
559    io.enq.ctrl_flow.instr, io.enq.ctrl_flow.pc, io.enq.ctrl_flow.exceptionVec.asUInt,
560    io.enq.ctrl_flow.intrVec.asUInt, io.enq.ctrl_flow.crossPageIPFFix)
561  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",
562    io.deq.cf_ctrl.ctrl.srcType(0), io.deq.cf_ctrl.ctrl.srcType(1), io.deq.cf_ctrl.ctrl.srcType(2),
563    io.deq.cf_ctrl.ctrl.lsrc(0), io.deq.cf_ctrl.ctrl.lsrc(1), io.deq.cf_ctrl.ctrl.lsrc(2),
564    io.deq.cf_ctrl.ctrl.ldest, io.deq.cf_ctrl.ctrl.fuType, io.deq.cf_ctrl.ctrl.fuOpType)
565  XSDebug("out: rfWen=%d fpWen=%d isXSTrap=%d noSpecExec=%d isBlocked=%d flushPipe=%d isRVF=%d imm=%x\n",
566    io.deq.cf_ctrl.ctrl.rfWen, io.deq.cf_ctrl.ctrl.fpWen, io.deq.cf_ctrl.ctrl.isXSTrap,
567    io.deq.cf_ctrl.ctrl.noSpecExec, io.deq.cf_ctrl.ctrl.blockBackward, io.deq.cf_ctrl.ctrl.flushPipe,
568    io.deq.cf_ctrl.ctrl.isRVF, io.deq.cf_ctrl.ctrl.imm)
569  XSDebug("out: excepVec=%b intrVec=%b\n",
570    io.deq.cf_ctrl.cf.exceptionVec.asUInt, io.deq.cf_ctrl.cf.intrVec.asUInt)
571}
572