/*************************************************************************************** * Copyright (c) 2014-2022 Zihao Yu, Nanjing University * * NEMU is licensed under Mulan PSL v2. * You can use this software according to the terms and conditions of the Mulan PSL v2. * You may obtain a copy of Mulan PSL v2 at: * http://license.coscl.org.cn/MulanPSL2 * * THIS SOFTWARE IS PROVIDED ON AN "AS IS" BASIS, WITHOUT WARRANTIES OF ANY KIND, * EITHER EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO NON-INFRINGEMENT, * MERCHANTABILITY OR FIT FOR A PARTICULAR PURPOSE. * * See the Mulan PSL v2 for more details. ***************************************************************************************/ #include "common.h" #include "local-include/reg.h" #include #include #include #define R(i) gpr(i) #define Mr vaddr_read #define Mw vaddr_write enum { TYPE_R, TYPE_I, TYPE_I_SHIFT, TYPE_U, TYPE_S, TYPE_B, TYPE_J, TYPE_N, // none }; #define src1R() do { *src1 = R(rs1); } while (0) #define src2R() do { *src2 = R(rs2); } while (0) #define immI() do { *imm = SEXT(BITS(i, 31, 20), 12); } while(0) #define immU() do { *imm = SEXT(BITS(i, 31, 12), 20) << 12; } while(0) #define immS() do { *imm = (SEXT(BITS(i, 31, 25), 7) << 5) | BITS(i, 11, 7); } while(0) #define immB() do { *imm = (SEXT(BITS(i, 31, 31), 1) << 12 | BITS(i, 30, 25) << 5 | BITS(i, 11, 8) << 1 | BITS(i, 8, 8) << 11); } while(0) #define immJ() do { *imm = (SEXT(BITS(i, 31, 31), 1) << 20) | BITS(i, 30, 21) << 1 | BITS(i, 20, 20) << 11 | BITS(i, 19, 12) << 12; } while(0) static void decode_operand(Decode *s, int *rd, word_t *src1, word_t *src2, word_t *imm, int type) { uint32_t i = s->isa.inst.val; int rs1 = BITS(i, 19, 15); int rs2 = BITS(i, 24, 20); *rd = BITS(i, 11, 7); switch (type) { case TYPE_R: src1R(); src2R(); break; case TYPE_I: src1R(); immI(); break; case TYPE_U: immU(); break; case TYPE_J: immJ(); break; case TYPE_S: src1R(); src2R(); immS(); break; case TYPE_B: src1R(); src2R(); immB(); break; } } static void do_branch(Decode *s, bool condition, word_t offset) { if (condition) { s->dnpc = s->pc + offset; } } static int decode_exec(Decode *s) { int rd = 0; word_t src1 = 0, src2 = 0, imm = 0; s->dnpc = s->snpc; #define INSTPAT_INST(s) ((s)->isa.inst.val) #define INSTPAT_MATCH(s, name, type, ... /* execute body */ ) { \ decode_operand(s, &rd, &src1, &src2, &imm, concat(TYPE_, type)); \ __VA_ARGS__ ; \ } INSTPAT_START(); INSTPAT("??????? ????? ????? ??? ????? 01101 11", lui , U, R(rd) = imm); INSTPAT("??????? ????? ????? ??? ????? 00101 11", auipc , U, R(rd) = s->pc + imm); INSTPAT("??????? ????? ????? ??? ????? 11011 11", jal , J, do {s->dnpc = s->pc + imm; R(rd) = s->pc + 4; } while(0)); INSTPAT("??????? ????? ????? ??? ????? 11001 11", jalr , I, do {s->dnpc = src1 + imm; R(rd) = s->pc + 4; } while(0)); INSTPAT("??????? ????? ????? 000 ????? 11000 11", beq , B, do_branch(s, src1 == src2, imm)); INSTPAT("??????? ????? ????? 001 ????? 11000 11", bne , B, do_branch(s, src1 != src2, imm)); INSTPAT("??????? ????? ????? 100 ????? 11000 11", blt , B, do_branch(s, (sword_t)src1 < (sword_t)src2, imm)); INSTPAT("??????? ????? ????? 101 ????? 11000 11", bge , B, do_branch(s, (sword_t)src1 >= (sword_t)src2, imm)); INSTPAT("??????? ????? ????? 110 ????? 11000 11", bltu , B, do_branch(s, src1 < src2, imm)); INSTPAT("??????? ????? ????? 111 ????? 11000 11", bgeu , B, do_branch(s, src1 >= src2, imm)); INSTPAT("??????? ????? ????? 000 ????? 00000 11", lb , I, R(rd) = SEXT(Mr(src1 + imm, 1), 8)); INSTPAT("??????? ????? ????? 001 ????? 00000 11", lh , I, R(rd) = SEXT(Mr(src1 + imm, 2), 16)); INSTPAT("??????? ????? ????? 010 ????? 00000 11", lw , I, R(rd) = SEXT(Mr(src1 + imm, 4), 32)); INSTPAT("??????? ????? ????? 100 ????? 00000 11", lbu , I, R(rd) = Mr(src1 + imm, 1)); INSTPAT("??????? ????? ????? 101 ????? 00000 11", lhu , I, R(rd) = Mr(src1 + imm, 2)); INSTPAT("??????? ????? ????? 000 ????? 01000 11", sb , S, Mw(src1 + imm, 1, src2)); INSTPAT("??????? ????? ????? 001 ????? 01000 11", sh , S, Mw(src1 + imm, 2, src2)); INSTPAT("??????? ????? ????? 010 ????? 01000 11", sw , S, Mw(src1 + imm, 4, src2)); INSTPAT("??????? ????? ????? 000 ????? 00100 11", addi , I, R(rd) = src1 + imm); INSTPAT("??????? ????? ????? 010 ????? 00100 11", slti , I, R(rd) = (sword_t)src1 < (sword_t)imm ? 1 : 0); INSTPAT("??????? ????? ????? 011 ????? 00100 11", sltiu , I, R(rd) = src1 < imm ? 1 : 0); INSTPAT("??????? ????? ????? 100 ????? 00100 11", xori , I, R(rd) = src1 ^ imm); INSTPAT("??????? ????? ????? 110 ????? 00100 11", ori , I, R(rd) = src1 | imm); INSTPAT("??????? ????? ????? 111 ????? 00100 11", andi , I, R(rd) = src1 & imm); INSTPAT("0000000 ????? ????? 001 ????? 00100 11", slli , I, R(rd) = src1 << imm); INSTPAT("0000000 ????? ????? 101 ????? 00100 11", srli , I, R(rd) = src1 >> imm); INSTPAT("0100000 ????? ????? 101 ????? 00100 11", srai , I, R(rd) = (sword_t)src1 >> (imm & 0x01F)); INSTPAT("0000000 ????? ????? 000 ????? 01100 11", add , R, R(rd) = src1 + src2); INSTPAT("0100000 ????? ????? 000 ????? 01100 11", sub , R, R(rd) = src1 - src2); INSTPAT("0000000 ????? ????? 001 ????? 01100 11", sll , R, R(rd) = src1 << src2); INSTPAT("0000000 ????? ????? 010 ????? 01100 11", slt , R, R(rd) = (sword_t)src1 < (sword_t)src2 ? 1 : 0); INSTPAT("0000000 ????? ????? 011 ????? 01100 11", sltu , R, R(rd) = src1 < src2 ? 1 : 0); INSTPAT("0000000 ????? ????? 100 ????? 01100 11", xor , R, R(rd) = src1 ^ src2); INSTPAT("0000000 ????? ????? 101 ????? 01100 11", srl , R, R(rd) = src1 >> src2); INSTPAT("0100000 ????? ????? 101 ????? 01100 11", sra , R, R(rd) = (sword_t)src1 >> (src2 & 0x01F)); INSTPAT("0000000 ????? ????? 110 ????? 01100 11", or , R, R(rd) = src1 | src2); INSTPAT("0000000 ????? ????? 111 ????? 01100 11", and , R, R(rd) = src1 & src2); INSTPAT("0000000 00001 00000 000 00000 11100 11", ebreak , N, NEMUTRAP(s->pc, R(10))); // R(10) is $a0 INSTPAT("??????? ????? ????? ??? ????? ????? ??", inv , N, INV(s->pc)); INSTPAT_END(); R(0) = 0; // reset $zero to 0 return 0; } int isa_exec_once(Decode *s) { s->isa.inst.val = inst_fetch(&s->snpc, 4); return decode_exec(s); }