//: instructions that (immediately) contain an argument to act with :(scenario add_imm32_to_r32) % Reg[3].i = 1; # op ModR/M SIB displacement immediate 81 c3 0a 0b 0c 0d # add 0x0d0c0b0a to EBX # ModR/M in binary: 11 (direct mode) 000 (add imm32) 011 (dest EBX) +run: combine imm32 0x0d0c0b0a with effective address +run: effective address is EBX +run: subop add +run: storing 0x0d0c0b0b :(before "End Single-Byte Opcodes") case 0x81: { // combine imm32 with r/m32 uint8_t modrm = next(); int32_t arg2 = imm32(); trace(2, "run") << "combine imm32 0x" << HEXWORD << arg2 << " with effective address" << end(); int32_t* arg1 = effective_address(modrm); uint8_t subop = (modrm>>3)&0x7; // middle 3 'reg opcode' bits switch (subop) { case 0: trace(2, "run") << "subop add" << end(); BINARY_ARITHMETIC_OP(+, *arg1, arg2); break; // End Op 81 Subops default: cerr << "unrecognized sub-opcode after 81: " << NUM(subop) << '\n'; exit(1); } break; } //: :(scenario add_imm32_to_mem_at_r32) % Reg[3].i = 0x60; % SET_WORD_IN_MEM(0x60, 1); # op ModR/M SIB displacement immediate 81 03 0a 0b 0c 0d # add 0x0d0c0b0a to *EBX # ModR/M in binary: 00 (indirect mode) 000 (add imm32) 011 (dest EBX) +run: combine imm32 0x0d0c0b0a with effective address +run: effective address is mem at address 0x60 (EBX) +run: subop add +run: storing 0x0d0c0b0b //:: subtract :(scenario subtract_imm32_from_eax) % Reg[EAX].i = 0x0d0c0baa; # op ModR/M SIB displacement immediate 2d 0a 0b 0c 0d # subtract 0x0d0c0b0a from EAX +run: subtract imm32 0x0d0c0b0a from EAX +run: storing 0x000000a0 :(before "End Single-Byte Opcodes") case 0x2d: { // subtract imm32 from EAX int32_t arg2 = imm32(); trace(2, "run") << "subtract imm32 0x" << HEXWORD << arg2 << " from EAX" << end(); BINARY_ARITHMETIC_OP(-, Reg[EAX].i, arg2); break; } //: :(scenario subtract_imm32_from_mem_at_r32) % Reg[3].i = 0x60; % SET_WORD_IN_MEM(0x60, 10); # op ModR/M SIB displacement immediate 81 2b 01 00 00 00 # subtract 1 from *EBX # ModR/M in binary: 00 (indirect mode) 101 (subtract imm32) 011 (dest EBX) +run: combine imm32 0x00000001 with effective address +run: effective address is mem at address 0x60 (EBX) +run: subop subtract +run: storing 0x00000009 :(before "End Op 81 Subops") case 5: { trace(2, "run") << "subop subtract" << end(); BINARY_ARITHMETIC_OP(-, *arg1, arg2); break; } //: :(scenario subtract_imm32_from_r32) % Reg[3].i = 10; # op ModR/M SIB displacement immediate 81 eb 01 00 00 00 # subtract 1 from EBX # ModR/M in binary: 11 (direct mode) 101 (subtract imm32) 011 (dest EBX) +run: combine imm32 0x00000001 with effective address +run: effective address is EBX +run: subop subtract +run: storing 0x00000009 //:: and :(scenario and_imm32_with_eax) % Reg[EAX].i = 0xff; # op ModR/M SIB displacement immediate 25 0a 0b 0c 0d # and 0x0d0c0b0a with EAX +run: and imm32 0x0d0c0b0a with EAX +run: storing 0x0000000a :(before "End Single-Byte Opcodes") case 0x25: { // and imm32 with EAX int32_t arg2 = imm32(); trace(2, "run") << "and imm32 0x" << HEXWORD << arg2 << " with EAX" << end(); BINARY_BITWISE_OP(&, Reg[EAX].i, arg2); break; } //: :(scenario and_imm32_with_mem_at_r32) % Reg[3].i = 0x60; % SET_WORD_IN_MEM(0x60, 0x000000ff); # op ModR/M SIB displacement immediate 81 23 0a 0b 0c 0d # and 0x0d0c0b0a with *EBX # ModR/M in binary: 00 (indirect mode) 100 (and imm32) 011 (dest EBX) +run: combine imm32 0x0d0c0b0a with effective address +run: effective address is mem at address 0x60 (EBX) +run: subop and +run: storing 0x0000000a :(before "End Op 81 Subops") case 4: { trace(2, "run") << "subop and" << end(); BINARY_BITWISE_OP(&, *arg1, arg2); break; } //: :(scenario and_imm32_with_r32) % Reg[3].i = 0xff; # op ModR/M SIB displacement immediate 81 e3 0a 0b 0c 0d # and 0x0d0c0b0a with EBX # ModR/M in binary: 11 (direct mode) 100 (and imm32) 011 (dest EBX) +run: combine imm32 0x0d0c0b0a with effective address +run: effective address is EBX +run: subop and +run: storing 0x0000000a //:: or :(scenario or_imm32_with_eax) % Reg[EAX].i = 0xd0c0b0a0; # op ModR/M SIB displacement immediate 0d 0a 0b 0c 0d # or 0x0d0c0b0a with EAX +run: or imm32 0x0d0c0b0a with EAX +run: storing 0xddccbbaa :(before "End Single-Byte Opcodes") case 0x0d: { // or imm32 with EAX int32_t arg2 = imm32(); trace(2, "run") << "or imm32 0x" << HEXWORD << arg2 << " with EAX" << end(); BINARY_BITWISE_OP(|, Reg[EAX].i, arg2); break; } //: :(scenario or_imm32_with_mem_at_r32) % Reg[3].i = 0x60; % SET_WORD_IN_MEM(0x60, 0xd0c0b0a0); # op ModR/M SIB displacement immediate 81 0b 0a 0b 0c 0d # or 0x0d0c0b0a with *EBX # ModR/M in binary: 00 (indirect mode) 001 (or imm32) 011 (dest EBX) +run: combine imm32 0x0d0c0b0a with effective address +run: effective address is mem at address 0x60 (EBX) +run: subop or +run: storing 0xddccbbaa :(before "End Op 81 Subops") case 1: { trace(2, "run") << "subop or" << end(); BINARY_BITWISE_OP(|, *arg1, arg2); break; } :(scenario or_imm32_with_r32) % Reg[3].i = 0xd0c0b0a0; # op ModR/M SIB displacement immediate 81 cb 0a 0b 0c 0d # or 0x0d0c0b0a with EBX # ModR/M in binary: 11 (direct mode) 001 (or imm32) 011 (dest EBX) +run: combine imm32 0x0d0c0b0a with effective address +run: effective address is EBX +run: subop or +run: storing 0xddccbbaa //:: xor :(scenario xor_imm32_with_eax) % Reg[EAX].i = 0xddccb0a0; # op ModR/M SIB displacement immediate 35 0a 0b 0c 0d # xor 0x0d0c0b0a with EAX +run: xor imm32 0x0d0c0b0a with EAX +run: storing 0xd0c0bbaa :(before "End Single-Byte Opcodes") case 0x35: { // xor imm32 with EAX int32_t arg2 = imm32(); trace(2, "run") << "xor imm32 0x" << HEXWORD << arg2 << " with EAX" << end(); BINARY_BITWISE_OP(^, Reg[EAX].i, arg2); break; } //: :(scenario xor_imm32_with_mem_at_r32) % Reg[3].i = 0x60; % SET_WORD_IN_MEM(0x60, 0xd0c0b0a0); # op ModR/M SIB displacement immediate 81 33 0a 0b 0c 0d # xor 0x0d0c0b0a with *EBX # ModR/M in binary: 00 (indirect mode) 110 (xor imm32) 011 (dest EBX) +run: combine imm32 0x0d0c0b0a with effective address +run: effective address is mem at address 0x60 (EBX) +run: subop xor +run: storing 0xddccbbaa :(before "End Op 81 Subops") case 6: { trace(2, "run") << "subop xor" << end(); BINARY_BITWISE_OP(^, *arg1, arg2); break; } :(scenario xor_imm32_with_r32) % Reg[3].i = 0xd0c0b0a0; # op ModR/M SIB displacement immediate 81 f3 0a 0b 0c 0d # xor 0x0d0c0b0a with EBX # ModR/M in binary: 11 (direct mode) 110 (xor imm32) 011 (dest EBX) +run: combine imm32 0x0d0c0b0a with effective address +run: effective address is EBX +run: subop xor +run: storing 0xddccbbaa //:: compare (cmp) :(scenario compare_imm32_with_eax_greater) % Reg[0].i = 0x0d0c0b0a; # op ModR/M SIB displacement immediate 3d 07 0b 0c 0d # compare 0x0d0c0b07 with EAX +run: compare EAX and imm32 0x0d0c0b07 +run: SF=0; ZF=0; OF=0 :(before "End Single-Byte Opcodes") case 0x3d: { // subtract imm32 from EAX int32_t arg1 = Reg[EAX].i; int32_t arg2 = imm32(); trace(2, "run") << "compare EAX and imm32 0x" << HEXWORD << arg2 << end(); int32_t tmp1 = arg1 - arg2; SF = (tmp1 < 0); ZF = (tmp1 == 0); int64_t tmp2 = arg1 - arg2; OF = (tmp1 != tmp2); trace(2, "run") << "SF=" << SF << "; ZF=" << ZF << "; OF=" << OF << end(); break; } :(scenario compare_imm32_with_eax_lesser) % Reg[0].i = 0x0d0c0b07; # op ModR/M SIB displacement immediate 3d 0a 0b 0c 0d # compare 0x0d0c0b0a with EAX +run: compare EAX and imm32 0x0d0c0b0a +run: SF=1; ZF=0; OF=0 :(scenario compare_imm32_with_eax_equal) % Reg[0].i = 0x0d0c0b0a; # op ModR/M SIB displacement immediate 3d 0a 0b 0c 0d # compare 0x0d0c0b0a with EAX +run: compare EAX and imm32 0x0d0c0b0a +run: SF=0; ZF=1; OF=0 //: :(scenario compare_imm32_with_r32_greater) % Reg[3].i = 0x0d0c0b0a; # op ModR/M SIB displacement immediate 81 fb 07 0b 0c 0d # compare 0x0d0c0b07 with EBX # ModR/M in binary: 11 (direct mode) 111 (compare imm32) 011 (dest EBX) +run: combine imm32 0x0d0c0b07 with effective address +run: effective address is EBX +run: SF=0; ZF=0; OF=0 :(before "End Op 81 Subops") case 7: { trace(2, "run") << "subop compare" << end(); int32_t tmp1 = *arg1 - arg2; SF = (tmp1 < 0); ZF = (tmp1 == 0); int64_t tmp2 = *arg1 - arg2; OF = (tmp1 != tmp2); trace(2, "run") << "SF=" << SF << "; ZF=" << ZF << "; OF=" << OF << end(); break; } :(scenario compare_imm32_with_r32_lesser) % Reg[3].i = 0x0d0c0b07; # op ModR/M SIB displacement immediate 81 fb 0a 0b 0c 0d # compare 0x0d0c0b0a with EBX # ModR/M in binary: 11 (direct mode) 111 (compare imm32) 011 (dest EBX) +run: combine imm32 0x0d0c0b0a with effective address +run: effective address is EBX +run: SF=1; ZF=0; OF=0 :(scenario compare_imm32_with_r32_equal) % Reg[3].i = 0x0d0c0b0a; # op ModR/M SIB displacement immediate 81 fb 0a 0b 0c 0d # compare 0x0d0c0b0a with EBX # ModR/M in binary: 11 (direct mode) 111 (compare imm32) 011 (dest EBX) +run: combine imm32 0x0d0c0b0a with effective address +run: effective address is EBX +run: SF=0; ZF=1; OF=0 :(scenario compare_imm32_with_mem_at_r32_greater) % Reg[3].i = 0x60; % SET_WORD_IN_MEM(0x60, 0x0d0c0b0a); # op ModR/M SIB displacement immediate 81 3b 07 0b 0c 0d # compare 0x0d0c0b07 with *EBX # ModR/M in binary: 00 (indirect mode) 111 (compare imm32) 011 (dest EBX) +run: combine imm32 0x0d0c0b07 with effective address +run: effective address is mem at address 0x60 (EBX) +run: SF=0; ZF=0; OF=0 :(scenario compare_imm32_with_mem_at_r32_lesser) % Reg[3].i = 0x60; % SET_WORD_IN_MEM(0x60, 0x0d0c0b07); # op ModR/M SIB displacement immediate 81 3b 0a 0b 0c 0d # compare 0x0d0c0b0a with *EBX # ModR/M in binary: 00 (indirect mode) 111 (compare imm32) 011 (dest EBX) +run: combine imm32 0x0d0c0b0a with effective address +run: effective address is mem at address 0x60 (EBX) +run: SF=1; ZF=0; OF=0 :(scenario compare_imm32_with_mem_at_r32_equal) % Reg[3].i = 0x0d0c0b0a; % Reg[3].i = 0x60; % SET_WORD_IN_MEM(0x60, 0x0d0c0b0a); # op ModR/M SIB displacement immediate 81 3b 0a 0b 0c 0d # compare 0x0d0c0b0a with *EBX # ModR/M in binary: 00 (indirect mode) 111 (compare imm32) 011 (dest EBX) +run: combine imm32 0x0d0c0b0a with effective address +run: effective address is mem at address 0x60 (EBX) +run: SF=0; ZF=1; OF=0 //:: copy (mov) :(scenario copy_imm32_to_r32) # op ModR/M SIB displacement immediate bb 0a 0b 0c 0d # copy 0x0d0c0b0a to EBX +run: copy imm32 0x0d0c0b0a to EBX :(before "End Single-Byte Opcodes") case 0xb8: case 0xb9: case 0xba: case 0xbb: case 0xbc: case 0xbd: case 0xbe: case 0xbf: { // copy imm32 to r32 uint8_t reg1 = op & 0x7; int32_t arg2 = imm32(); trace(2, "run") << "copy imm32 0x" << HEXWORD << arg2 << " to " << rname(reg1) << end(); Reg[reg1].i = arg2; break; } //: :(scenario copy_imm32_to_mem_at_r32) % Reg[3].i = 0x60; # op ModR/M SIB displacement immediate c7 03 0a 0b 0c 0d # copy 0x0d0c0b0a to *EBX # ModR/M in binary: 00 (indirect mode) 000 (unused) 011 (dest EBX) +run: copy imm32 0x0d0c0b0a to effective address +run: effective address is mem at address 0x60 (EBX) :(before "End Single-Byte Opcodes") case 0xc7: { // copy imm32 to r32 uint8_t modrm = next(); int32_t arg2 = imm32(); trace(2, "run") << "copy imm32 0x" << HEXWORD << arg2 << " to effective address" << end(); int32_t* arg1 = effective_address(modrm); *arg1 = arg2; break; } //:: push :(scenario push_imm32) % Reg[ESP].u = 0x14; # op ModR/M SIB displacement immediate 68 af 00 00 00 # push *EAX to stack +run: push imm32 0x000000af +run: ESP is now 0x00000010 +run: contents at ESP: 0x000000af :(before "End Single-Byte Opcodes") case 0x68: { int32_t val = imm32(); trace(2, "run") << "push imm32 0x" << HEXWORD << val << end(); Reg[ESP].u -= 4; *reinterpret_cast(&Mem.at(Reg[ESP].u)) = val; trace(2, "run") << "ESP is now 0x" << HEXWORD << Reg[ESP].u << end(); trace(2, "run") << "contents at ESP: 0x" << HEXWORD << *reinterpret_cast(&Mem.at(Reg[ESP].u)) << end(); break; }