diff options
| -rw-r--r-- | subx/010core.cc | 26 |
1 files changed, 13 insertions, 13 deletions
diff --git a/subx/010core.cc b/subx/010core.cc index 06f04b69..87c06d90 100644 --- a/subx/010core.cc +++ b/subx/010core.cc @@ -17,10 +17,10 @@ union reg { uint32_t u; }; :(before "End Globals") -reg R[NUM_INT_REGISTERS] = { {0} }; +reg Reg[NUM_INT_REGISTERS] = { {0} }; uint32_t EIP = 0; :(before "End Reset") -bzero(R, sizeof(R)); +bzero(Reg, sizeof(Reg)); EIP = 0; //:: simulated flag registers; just a subset that we care about @@ -56,10 +56,10 @@ SF = ZF = OF = false; //:: simulated RAM :(before "End Globals") -vector<uint8_t> Memory; +vector<uint8_t> Mem; uint32_t End_of_program = 0; :(before "End Reset") -Memory.resize(1024); +Mem.resize(1024); End_of_program = 0; //:: core interpreter loop @@ -69,10 +69,10 @@ End_of_program = 0; # instruction on one line. # # x86 instructions consist of the following parts (see cheatsheet.pdf): -# opcode ModRM SIB displacement immediate -# instruction mod, reg, R/M bits scale, index, base -# 1-3 bytes 0/1 byte 0/1 byte 0/1/2/4 bytes 0/1/2/4 bytes - 05 0a 0b 0c 0d # add 0x0d0c0b0a to EAX +# opcode ModR/M SIB displacement immediate +# instruction mod, reg, Reg/Mem bits scale, index, base +# 1-3 bytes 0/1 byte 0/1 byte 0/1/2/4 bytes 0/1/2/4 bytes + 05 0a 0b 0c 0d # add 0x0d0c0b0a to EAX # All hex bytes must be exactly 2 characters each. No '0x' prefixes. +load: 1 -> 05 +load: 2 -> 0a @@ -103,8 +103,8 @@ void run_one_instruction() { case 0x05: { // add imm32 to EAX int32_t arg2 = imm32(); trace(2, "run") << "add imm32 0x" << HEXWORD << arg2 << " to reg EAX" << end(); - BINARY_ARITHMETIC_OP(+, R[EAX].i, arg2); - trace(98, "reg") << "storing 0x" << HEXWORD << R[EAX].i << " in reg EAX" << end(); + BINARY_ARITHMETIC_OP(+, Reg[EAX].i, arg2); + trace(98, "reg") << "storing 0x" << HEXWORD << Reg[EAX].i << " in reg EAX" << end(); break; } // End Single-Byte Opcodes @@ -154,8 +154,8 @@ void load_program(const string& text_bytes) { raise << "input program truncated mid-byte\n" << end(); return; } - Memory.at(addr) = to_byte(c1, c2); - trace(99, "load") << addr << " -> " << HEXBYTE << static_cast<int>(Memory.at(addr)) << end(); // ugly that iostream doesn't print uint8_t as an integer + Mem.at(addr) = to_byte(c1, c2); + trace(99, "load") << addr << " -> " << HEXBYTE << static_cast<int>(Mem.at(addr)) << end(); // ugly that iostream doesn't print uint8_t as an integer addr++; } End_of_program = addr; @@ -198,7 +198,7 @@ uint8_t to_hex_num(char c) { } inline uint8_t next() { - return Memory.at(EIP++); + return Mem.at(EIP++); } // read a 32-bit immediate in little-endian order from the instruction stream |