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This commit is contained in:
Antoni Piasecki
2026-03-09 15:26:41 +01:00
parent daad92956e
commit cc868fa6ec
1 changed files with 125 additions and 13 deletions
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140
riscv64.cc
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@@ -46,6 +46,7 @@ enum Op {
ADDI,
ADDIW,
ADDW,
AMOSWAP_D,
AND,
ANDI,
AUIPC,
@@ -60,21 +61,32 @@ enum Op {
C_ADDIW,
C_ADDI16SP,
C_ADDI4SPN,
C_ADDW,
C_AND,
C_ANDI,
C_BEQZ,
C_BNEZ,
C_EBREAK,
C_FLDSP,
C_J,
C_JALR,
C_JR,
C_LD,
C_LDSP,
C_LI,
C_LUI,
C_LW,
C_MV,
C_OR,
C_SD,
C_SDSP,
C_SRAI,
C_SRLI,
C_SLLI,
C_SUB,
C_SUBW,
C_SW,
C_XOR,
DIV,
DIVU,
DIVUW,
@@ -161,8 +173,10 @@ enum class Format {
U,
J,
CI,
CJ,
CSS,
CR,
CR1,
CL,
R_ATOMIC,
R_ATOMIC_LR
@@ -173,12 +187,13 @@ struct OpDef {
Format format;
};
static constexpr std::array<OpDef, 88> OP_TABLE = {{
static constexpr std::array<OpDef, 100> OP_TABLE = {{
{"???", Format::NONE},
{"add", Format::R},
{"addi", Format::I},
{"addiw", Format::I},
{"addw", Format::R},
{"amoswap.d", Format::R_ATOMIC},
{"and", Format::R},
{"andi", Format::I},
{"auipc", Format::U},
@@ -193,21 +208,32 @@ static constexpr std::array<OpDef, 88> OP_TABLE = {{
{"c.addiw", Format::CI},
{"c.addi16sp", Format::CI},
{"c.addi4spn", Format::CI},
{"c.addw", Format::CI},
{"c.and", Format::CR},
{"c.andi", Format::CI},
{"c.beqz", Format::B},
{"c.bnez", Format::B},
{"c.ebreak", Format::CR},
{"c.fldsp", Format::CSS},
{"c.jalr", Format::CR},
{"c.j", Format::CJ},
{"c.jalr", Format::CR1},
{"c.jr", Format::CR1},
{"c.ld", Format::CL},
{"c.ldsp", Format::CL},
{"c.li", Format::CI},
{"c.lui", Format::CI},
{"c.lw", Format::CL},
{"c.mv", Format::CR},
{"c.or", Format::CR},
{"c.sd", Format::S},
{"c.sdsp", Format::CSS},
{"c.slli", Format::CI},
{"c.srai", Format::CI},
{"c.srli", Format::CI},
{"c.sub", Format::CR},
{"c.subw", Format::CR},
{"c.sw", Format::S},
{"c.xor", Format::CR},
{"div", Format::R},
{"divu", Format::R},
{"divuw", Format::R},
@@ -308,6 +334,7 @@ public:
Ins ins = decode_raw(raw);
ins.length = ((raw & 0b11) == 0b11) ? 4 : 2;
m_decoded[offset / 2] = ins;
disassemble_ins(ins);
offset += ins.length;
}
@@ -318,13 +345,13 @@ public:
void disassemble_all() {
m_pc = m_code_section.offset;
while (m_pc < m_code_section.offset + m_code_section.size) {
disassemble_one();
}
}
void disassemble_one() {
Ins ins = m_decoded[(m_pc - m_code_section.offset) / 2];
disassemble_ins(ins);
m_pc += ins.length;
}
}
void disassemble_ins(Ins ins) {
const OpDef &def = OP_TABLE[ins.op];
switch (def.format) {
@@ -361,12 +388,18 @@ public:
case Format::CI:
std::println("{} {}, {}", def.mnemonic, REGS[ins.rd], ins.imm);
break;
case Format::CJ:
std::println("{} {}", def.mnemonic, ins.imm);
break;
case Format::CSS:
std::println("{} {}, {}(sp)", def.mnemonic, REGS[ins.rs2], ins.imm);
break;
case Format::CR:
std::println("{} {}, {}", def.mnemonic, REGS[ins.rd], REGS[ins.rs2]);
break;
case Format::CR1:
std::println("{} {}", def.mnemonic, REGS[ins.rs1]);
break;
case Format::CL:
std::println("{} {}, {}({})", def.mnemonic, REGS[ins.rd], ins.imm,
REGS[ins.rs1]);
@@ -382,8 +415,6 @@ public:
std::println("{}", def.mnemonic);
break;
}
m_pc += ins.length;
}
void dump() {
@@ -908,6 +939,85 @@ private:
}
}; break;
case 0b100: {
u8 funct2 = (raw >> 10) & 0b11;
if (funct2 == 0b11) {
bool bit12 = (raw >> 12) & 0b1;
i.rs2 = ((raw >> 2) & 0b111) + 8;
u8 sub_op = (raw >> 5) & 0b11;
if (bit12 == 0) {
switch (sub_op) {
case 0b00:
i.op = Op::C_SUB;
break;
case 0b01:
i.op = Op::C_XOR;
break;
case 0b10:
i.op = Op::C_OR;
break;
case 0b11:
i.op = Op::C_AND;
break;
default:
std::println(
stderr,
"C: opcode=01: funct3=100: bit12=0: unrecognized sub_op");
exit(1);
}
} else {
switch (sub_op) {
case 0b00:
i.op = Op::C_SUBW;
break;
case 0b01:
i.op = Op::C_ADDW;
break;
default:
std::println(stderr,
"C: opcode=01: funct3=100: bit12=1: unrecognized "
"sub_op: {:b}",
sub_op);
exit(1);
}
}
} else {
i.rd = ((raw >> 7) & 0b111) + 8;
i.rs1 = i.rd;
i.imm = ((raw >> 2) & 0b11111) | (((raw >> 12) & 0b1) << 5);
switch (funct2) {
case 0b00:
i.op = Op::C_SRLI;
break;
case 0b01:
i.op = Op::C_SRAI;
break;
case 0b10:
i.imm = (i.imm << 26) >> 26;
i.op = Op::C_ANDI;
break;
default:
std::println(
stderr,
"C: opcode=01: funct3=100: funct2!=11: unrecognized funct2");
exit(1);
}
}
}; break;
case 0b101: {
i.rd = 0;
i.imm = (((raw >> 12) & 0b1) << 11) | (((raw >> 11) & 0b1) << 4) |
(((raw >> 9) & 0b11) << 8) | (((raw >> 8) & 0b1) << 10) |
(((raw >> 7) & 0b1) << 6) | (((raw >> 6) & 0b1) << 7) |
(((raw >> 5) & 0b1) << 3) | (((raw >> 3) & 0b11) << 1) |
(((raw >> 2) & 0b1) << 5);
i.imm = (i.imm << 20) >> 20;
i.op = Op::C_J;
}; break;
case 0b110: {
i.rs1 = ((raw >> 7) & 0b111) + 8;
i.rs2 = 0;
@@ -947,7 +1057,6 @@ private:
}; break;
case 0b011: {
i.rs1 = 2;
i.rd = (raw >> 7) & 0b11111;
i.imm = (((raw >> 12) & 0b1) << 5) | (((raw >> 5) & 0b11) << 3) |
(((raw >> 2) & 0b111) << 6);
i.op = Op::C_LDSP;
@@ -958,10 +1067,10 @@ private:
if (bit12 == 0) {
if (i.rs2 == 0) {
std::println(
stderr,
"C: opcode=10: funct3=100: bit12=0: rs2=0: unimplemented");
exit(1);
i.rs1 = i.rd;
i.rd = 0;
i.imm = 0;
i.op = Op::C_JR;
} else {
i.rs1 = 0;
i.op = Op::C_MV;
@@ -1260,6 +1369,9 @@ private:
if (funct3 == 0b011) {
switch (funct7) {
case 0b00001: {
i.op = Op::AMOSWAP_D;
}; break;
case 0b00010: {
i.op = Op::LR_D;
}; break;