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Diffstat (limited to 'subx/013indirect_addressing.cc')
-rw-r--r-- | subx/013indirect_addressing.cc | 561 |
1 files changed, 561 insertions, 0 deletions
diff --git a/subx/013indirect_addressing.cc b/subx/013indirect_addressing.cc new file mode 100644 index 00000000..df56a248 --- /dev/null +++ b/subx/013indirect_addressing.cc @@ -0,0 +1,561 @@ +//: operating on memory at the address provided by some register +//: we'll now start providing data in a separate segment + +:(scenario add_r32_to_mem_at_r32) +% Reg[EBX].i = 0x10; +% Reg[EAX].i = 0x60; +== 0x01 # code segment +# op ModR/M SIB displacement immediate + 01 18 # add EBX to *EAX +# ModR/M in binary: 00 (indirect mode) 011 (src EAX) 000 (dest EAX) +== 0x60 # data segment +01 00 00 00 # 1 ++run: add EBX to r/m32 ++run: effective address is 0x60 (EAX) ++run: storing 0x00000011 + +:(before "End Mod Special-cases(addr)") +case 0: // indirect addressing + switch (rm) { + default: // address in register + trace(2, "run") << "effective address is 0x" << std::hex << Reg[rm].u << " (" << rname(rm) << ")" << end(); + addr = Reg[rm].u; + break; + // End Mod 0 Special-cases(addr) + } + break; + +//: + +:(scenario add_mem_at_r32_to_r32) +% Reg[EAX].i = 0x60; +% Reg[EBX].i = 0x10; +== 0x01 # code segment +# op ModR/M SIB displacement immediate + 03 18 # add *EAX to EBX +# ModR/M in binary: 00 (indirect mode) 011 (src EAX) 000 (dest EAX) +== 0x60 # data segment +01 00 00 00 # 1 ++run: add r/m32 to EBX ++run: effective address is 0x60 (EAX) ++run: storing 0x00000011 + +:(before "End Single-Byte Opcodes") +case 0x03: { // add r/m32 to r32 + uint8_t modrm = next(); + uint8_t arg1 = (modrm>>3)&0x7; + trace(2, "run") << "add r/m32 to " << rname(arg1) << end(); + const int32_t* arg2 = effective_address(modrm); + BINARY_ARITHMETIC_OP(+, Reg[arg1].i, *arg2); + break; +} + +//:: subtract + +:(scenario subtract_r32_from_mem_at_r32) +% Reg[EAX].i = 0x60; +% Reg[EBX].i = 1; +== 0x01 # code segment +# op ModR/M SIB displacement immediate + 29 18 # subtract EBX from *EAX +# ModR/M in binary: 00 (indirect mode) 011 (src EAX) 000 (dest EAX) +== 0x60 # data segment +0a 00 00 00 # 10 ++run: subtract EBX from r/m32 ++run: effective address is 0x60 (EAX) ++run: storing 0x00000009 + +//: + +:(scenario subtract_mem_at_r32_from_r32) +% Reg[EAX].i = 0x60; +% Reg[EBX].i = 10; +== 0x01 # code segment +# op ModR/M SIB displacement immediate + 2b 18 # subtract *EAX from EBX +# ModR/M in binary: 00 (indirect mode) 011 (src EAX) 000 (dest EAX) +== 0x60 # data segment +01 00 00 00 # 1 ++run: subtract r/m32 from EBX ++run: effective address is 0x60 (EAX) ++run: storing 0x00000009 + +:(before "End Single-Byte Opcodes") +case 0x2b: { // subtract r/m32 from r32 + uint8_t modrm = next(); + uint8_t arg1 = (modrm>>3)&0x7; + trace(2, "run") << "subtract r/m32 from " << rname(arg1) << end(); + const int32_t* arg2 = effective_address(modrm); + BINARY_ARITHMETIC_OP(-, Reg[arg1].i, *arg2); + break; +} + +//:: and + +:(scenario and_r32_with_mem_at_r32) +% Reg[EAX].i = 0x60; +% Reg[EBX].i = 0xff; +== 0x01 # code segment +# op ModR/M SIB displacement immediate + 21 18 # and EBX with *EAX +# ModR/M in binary: 00 (indirect mode) 011 (src EAX) 000 (dest EAX) +== 0x60 # data segment +0d 0c 0b 0a # 0x0a0b0c0d ++run: and EBX with r/m32 ++run: effective address is 0x60 (EAX) ++run: storing 0x0000000d + +//: + +:(scenario and_mem_at_r32_with_r32) +% Reg[EAX].i = 0x60; +% Reg[EBX].i = 0x0a0b0c0d; +== 0x01 # code segment +# op ModR/M SIB displacement immediate + 23 18 # and *EAX with EBX +# ModR/M in binary: 00 (indirect mode) 011 (src EAX) 000 (dest EAX) +== 0x60 # data segment +ff 00 00 00 # 0xff ++run: and r/m32 with EBX ++run: effective address is 0x60 (EAX) ++run: storing 0x0000000d + +:(before "End Single-Byte Opcodes") +case 0x23: { // and r/m32 with r32 + uint8_t modrm = next(); + uint8_t arg1 = (modrm>>3)&0x7; + trace(2, "run") << "and r/m32 with " << rname(arg1) << end(); + const int32_t* arg2 = effective_address(modrm); + BINARY_BITWISE_OP(&, Reg[arg1].u, *arg2); + break; +} + +//:: or + +:(scenario or_r32_with_mem_at_r32) +% Reg[EAX].i = 0x60; +% Reg[EBX].i = 0xa0b0c0d0; +== 0x01 # code segment +# op ModR/M SIB displacement immediate + 09 18 # or EBX with *EAX +# ModR/M in binary: 00 (indirect mode) 011 (src EAX) 000 (dest EAX) +== 0x60 # data segment +0d 0c 0b 0a # 0x0a0b0c0d ++run: or EBX with r/m32 ++run: effective address is 0x60 (EAX) ++run: storing 0xaabbccdd + +//: + +:(scenario or_mem_at_r32_with_r32) +% Reg[EAX].i = 0x60; +% Reg[EBX].i = 0xa0b0c0d0; +== 0x01 # code segment +# op ModR/M SIB displacement immediate + 0b 18 # or *EAX with EBX +# ModR/M in binary: 00 (indirect mode) 011 (src EAX) 000 (dest EAX) +== 0x60 # data segment +0d 0c 0b 0a # 0x0a0b0c0d ++run: or r/m32 with EBX ++run: effective address is 0x60 (EAX) ++run: storing 0xaabbccdd + +:(before "End Single-Byte Opcodes") +case 0x0b: { // or r/m32 with r32 + uint8_t modrm = next(); + uint8_t arg1 = (modrm>>3)&0x7; + trace(2, "run") << "or r/m32 with " << rname(arg1) << end(); + const int32_t* arg2 = effective_address(modrm); + BINARY_BITWISE_OP(|, Reg[arg1].u, *arg2); + break; +} + +//:: xor + +:(scenario xor_r32_with_mem_at_r32) +% Reg[EAX].i = 0x60; +% Reg[EBX].i = 0xa0b0c0d0; +== 0x01 # code segment +# op ModR/M SIB displacement immediate + 31 18 # xor EBX with *EAX +# ModR/M in binary: 00 (indirect mode) 011 (src EAX) 000 (dest EAX) +== 0x60 # data segment +0d 0c bb aa # 0xaabb0c0d ++run: xor EBX with r/m32 ++run: effective address is 0x60 (EAX) ++run: storing 0x0a0bccdd + +//: + +:(scenario xor_mem_at_r32_with_r32) +% Reg[EAX].i = 0x60; +% Reg[EBX].i = 0xa0b0c0d0; +== 0x01 # code segment +# op ModR/M SIB displacement immediate + 33 18 # xor *EAX with EBX +# ModR/M in binary: 00 (indirect mode) 011 (src EAX) 000 (dest EAX) +== 0x60 # data segment +0d 0c 0b 0a # 0x0a0b0c0d ++run: xor r/m32 with EBX ++run: effective address is 0x60 (EAX) ++run: storing 0xaabbccdd + +:(before "End Single-Byte Opcodes") +case 0x33: { // xor r/m32 with r32 + uint8_t modrm = next(); + uint8_t arg1 = (modrm>>3)&0x7; + trace(2, "run") << "xor r/m32 with " << rname(arg1) << end(); + const int32_t* arg2 = effective_address(modrm); + BINARY_BITWISE_OP(|, Reg[arg1].u, *arg2); + break; +} + +//:: not + +:(scenario not_r32_with_mem_at_r32) +% Reg[EBX].i = 0x60; +== 0x01 # code segment +# op ModR/M SIB displacement immediate + f7 03 # negate *EBX +# ModR/M in binary: 00 (indirect mode) 000 (unused) 011 (dest EBX) +== 0x60 # data segment +ff 00 0f 0f # 0x0f0f00ff ++run: 'not' of r/m32 ++run: effective address is 0x60 (EBX) ++run: storing 0xf0f0ff00 + +//:: compare (cmp) + +:(scenario compare_mem_at_r32_with_r32_greater) +% Reg[EAX].i = 0x60; +% Reg[EBX].i = 0x0a0b0c07; +== 0x01 # code segment +# op ModR/M SIB displacement immediate + 39 18 # compare EBX with *EAX +# ModR/M in binary: 00 (indirect mode) 011 (src EAX) 000 (dest EAX) +== 0x60 # data segment +0d 0c 0b 0a # 0x0a0b0c0d ++run: compare EBX with r/m32 ++run: effective address is 0x60 (EAX) ++run: SF=0; ZF=0; OF=0 + +:(scenario compare_mem_at_r32_with_r32_lesser) +% Reg[EAX].i = 0x60; +% Reg[EBX].i = 0x0a0b0c0d; +== 0x01 # code segment +# op ModR/M SIB displacement immediate + 39 18 # compare EBX with *EAX +# ModR/M in binary: 00 (indirect mode) 011 (src EAX) 000 (dest EAX) +== 0x60 # data segment +07 0c 0b 0a # 0x0a0b0c0d ++run: compare EBX with r/m32 ++run: effective address is 0x60 (EAX) ++run: SF=1; ZF=0; OF=0 + +:(scenario compare_mem_at_r32_with_r32_equal) +% Reg[EAX].i = 0x60; +% Reg[EBX].i = 0x0a0b0c0d; +== 0x01 # code segment +# op ModR/M SIB displacement immediate + 39 18 # compare EBX with *EAX +# ModR/M in binary: 00 (indirect mode) 011 (src EAX) 000 (dest EAX) +== 0x60 # data segment +0d 0c 0b 0a # 0x0a0b0c0d ++run: compare EBX with r/m32 ++run: effective address is 0x60 (EAX) ++run: SF=0; ZF=1; OF=0 + +//: + +:(scenario compare_r32_with_mem_at_r32_greater) +% Reg[EAX].i = 0x60; +% Reg[EBX].i = 0x0a0b0c0d; +== 0x01 # code segment +# op ModR/M SIB displacement immediate + 3b 18 # compare *EAX with EBX +# ModR/M in binary: 00 (indirect mode) 011 (src EAX) 000 (dest EAX) +== 0x60 # data segment +07 0c 0b 0a # 0x0a0b0c0d ++run: compare r/m32 with EBX ++run: effective address is 0x60 (EAX) ++run: SF=0; ZF=0; OF=0 + +:(before "End Single-Byte Opcodes") +case 0x3b: { // set SF if r32 < r/m32 + uint8_t modrm = next(); + uint8_t reg1 = (modrm>>3)&0x7; + trace(2, "run") << "compare r/m32 with " << rname(reg1) << end(); + int32_t arg1 = Reg[reg1].i; + int32_t* arg2 = effective_address(modrm); + 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_r32_with_mem_at_r32_lesser) +% Reg[EAX].i = 0x60; +% Reg[EBX].i = 0x0a0b0c07; +== 0x01 # code segment +# op ModR/M SIB displacement immediate + 3b 18 # compare *EAX with EBX +# ModR/M in binary: 00 (indirect mode) 011 (src EAX) 000 (dest EAX) +== 0x60 # data segment +0d 0c 0b 0a # 0x0a0b0c0d ++run: compare r/m32 with EBX ++run: effective address is 0x60 (EAX) ++run: SF=1; ZF=0; OF=0 + +:(scenario compare_r32_with_mem_at_r32_equal) +% Reg[EAX].i = 0x60; +% Reg[EBX].i = 0x0a0b0c0d; +== 0x01 # code segment +# op ModR/M SIB displacement immediate + 3b 18 # compare *EAX with EBX +# ModR/M in binary: 00 (indirect mode) 011 (src EAX) 000 (dest EAX) +== 0x60 # data segment +0d 0c 0b 0a # 0x0a0b0c0d ++run: compare r/m32 with EBX ++run: effective address is 0x60 (EAX) ++run: SF=0; ZF=1; OF=0 + +//:: copy (mov) + +:(scenario copy_r32_to_mem_at_r32) +% Reg[EBX].i = 0xaf; +% Reg[EAX].i = 0x60; +# op ModR/M SIB displacement immediate + 89 18 # copy EBX to *EAX +# ModR/M in binary: 00 (indirect mode) 011 (src EAX) 000 (dest EAX) ++run: copy EBX to r/m32 ++run: effective address is 0x60 (EAX) ++run: storing 0x000000af + +//: + +:(scenario copy_mem_at_r32_to_r32) +% Reg[EAX].i = 0x60; +== 0x01 # code segment +# op ModR/M SIB displacement immediate + 8b 18 # copy *EAX to EBX +# ModR/M in binary: 00 (indirect mode) 011 (src EAX) 000 (dest EAX) +== 0x60 # data segment +af 00 00 00 # 0xaf ++run: copy r/m32 to EBX ++run: effective address is 0x60 (EAX) ++run: storing 0x000000af + +:(before "End Single-Byte Opcodes") +case 0x8b: { // copy r32 to r/m32 + uint8_t modrm = next(); + uint8_t reg1 = (modrm>>3)&0x7; + trace(2, "run") << "copy r/m32 to " << rname(reg1) << end(); + int32_t* arg2 = effective_address(modrm); + Reg[reg1].i = *arg2; + trace(2, "run") << "storing 0x" << HEXWORD << *arg2 << end(); + break; +} + +//:: jump + +:(scenario jump_mem_at_r32) +% Reg[EAX].i = 0x60; +== 0x01 # code segment +# op ModR/M SIB displacement immediate + ff 20 # jump to *EAX +# ModR/M in binary: 00 (indirect mode) 100 (jump to r/m32) 000 (src EAX) + 05 00 00 00 01 + 05 00 00 00 02 +== 0x60 # data segment +08 00 00 00 # 8 ++run: inst: 0x00000001 ++run: jump to r/m32 ++run: effective address is 0x60 (EAX) ++run: jumping to 0x00000008 ++run: inst: 0x00000008 +-run: inst: 0x00000003 + +:(before "End Single-Byte Opcodes") +case 0xff: { + uint8_t modrm = next(); + uint8_t subop = (modrm>>3)&0x7; // middle 3 'reg opcode' bits + switch (subop) { + case 4: { // jump to r/m32 + trace(2, "run") << "jump to r/m32" << end(); + int32_t* arg2 = effective_address(modrm); + EIP = *arg2; + trace(2, "run") << "jumping to 0x" << HEXWORD << EIP << end(); + break; + } + // End Op ff Subops + } + break; +} + +//:: push + +:(scenario push_mem_at_r32) +% Reg[EAX].i = 0x60; +% Reg[ESP].u = 0x14; +== 0x01 # code segment +# op ModR/M SIB displacement immediate + ff 30 # push *EAX to stack +# ModR/M in binary: 00 (indirect mode) 110 (push r/m32) 000 (src EAX) +== 0x60 # data segment +af 00 00 00 # 0xaf ++run: push r/m32 ++run: effective address is 0x60 (EAX) ++run: decrementing ESP to 0x00000010 ++run: pushing value 0x000000af + +:(before "End Op ff Subops") +case 6: { // push r/m32 to stack + trace(2, "run") << "push r/m32" << end(); + const int32_t* val = effective_address(modrm); + push(*val); + break; +} + +//:: pop + +:(scenario pop_mem_at_r32) +% Reg[EAX].i = 0x60; +% Reg[ESP].u = 0x10; +== 0x01 # code segment +# op ModR/M SIB displacement immediate + 8f 00 # pop stack into *EAX +# ModR/M in binary: 00 (indirect mode) 000 (pop r/m32) 000 (dest EAX) +== 0x10 # data segment +30 00 00 00 # 0x30 ++run: pop into r/m32 ++run: effective address is 0x60 (EAX) ++run: popping value 0x00000030 ++run: incrementing ESP to 0x00000014 + +:(before "End Single-Byte Opcodes") +case 0x8f: { // pop stack into r/m32 + uint8_t modrm = next(); + uint8_t subop = (modrm>>3)&0x7; + switch (subop) { + case 0: { + trace(2, "run") << "pop into r/m32" << end(); + int32_t* dest = effective_address(modrm); + *dest = pop(); + break; + } + } + break; +} + +//:: special-case for loading address from disp32 rather than register + +:(scenario add_r32_to_mem_at_displacement) +% Reg[EBX].i = 0x10; // source +== 0x01 # code segment +# op ModR/M SIB displacement immediate + 01 1d 60 00 00 00 # add EBX to *0x60 +# ModR/M in binary: 00 (indirect mode) 011 (src EBX) 101 (dest in disp32) +== 0x60 # data segment +01 00 00 00 # 1 ++run: add EBX to r/m32 ++run: effective address is 0x60 (disp32) ++run: storing 0x00000011 + +:(before "End Mod 0 Special-cases(addr)") +case 5: // exception: mod 0b00 rm 0b101 => incoming disp32 + addr = imm32(); + trace(2, "run") << "effective address is 0x" << std::hex << addr << " (disp32)" << end(); + break; + +//: + +:(scenario add_r32_to_mem_at_r32_plus_disp8) +% Reg[EBX].i = 0x10; // source +% Reg[EAX].i = 0x5e; // dest +== 0x01 # code segment +# op ModR/M SIB displacement immediate + 01 58 02 # add EBX to *(EAX+2) +# ModR/M in binary: 01 (indirect+disp8 mode) 011 (src EBX) 000 (dest EAX) +== 0x60 # data segment +01 00 00 00 # 1 ++run: add EBX to r/m32 ++run: effective address is initially 0x5e (EAX) ++run: effective address is 0x60 (after adding disp8) ++run: storing 0x00000011 + +:(before "End Mod Special-cases(addr)") +case 1: // indirect + disp8 addressing + switch (rm) { + default: + addr = Reg[rm].u; + trace(2, "run") << "effective address is initially 0x" << std::hex << addr << " (" << rname(rm) << ")" << end(); + break; + // End Mod 1 Special-cases(addr) + } + if (addr > 0) { + addr += static_cast<int8_t>(next()); + trace(2, "run") << "effective address is 0x" << std::hex << addr << " (after adding disp8)" << end(); + } + break; + +:(scenario add_r32_to_mem_at_r32_plus_negative_disp8) +% Reg[EBX].i = 0x10; // source +% Reg[EAX].i = 0x61; // dest +== 0x01 # code segment +# op ModR/M SIB displacement immediate + 01 58 ff # add EBX to *(EAX-1) +# ModR/M in binary: 01 (indirect+disp8 mode) 011 (src EBX) 000 (dest EAX) +== 0x60 # data segment +01 00 00 00 # 1 ++run: add EBX to r/m32 ++run: effective address is initially 0x61 (EAX) ++run: effective address is 0x60 (after adding disp8) ++run: storing 0x00000011 + +//: + +:(scenario add_r32_to_mem_at_r32_plus_disp32) +% Reg[EBX].i = 0x10; // source +% Reg[EAX].i = 0x5e; // dest +== 0x01 # code segment +# op ModR/M SIB displacement immediate + 01 98 02 00 00 00 # add EBX to *(EAX+2) +# ModR/M in binary: 10 (indirect+disp32 mode) 011 (src EBX) 000 (dest EAX) +== 0x60 # data segment +01 00 00 00 # 1 ++run: add EBX to r/m32 ++run: effective address is initially 0x5e (EAX) ++run: effective address is 0x60 (after adding disp32) ++run: storing 0x00000011 + +:(before "End Mod Special-cases(addr)") +case 2: // indirect + disp32 addressing + switch (rm) { + default: + addr = Reg[rm].u; + trace(2, "run") << "effective address is initially 0x" << std::hex << addr << " (" << rname(rm) << ")" << end(); + break; + // End Mod 2 Special-cases(addr) + } + if (addr > 0) { + addr += imm32(); + trace(2, "run") << "effective address is 0x" << std::hex << addr << " (after adding disp32)" << end(); + } + break; + +:(scenario add_r32_to_mem_at_r32_plus_negative_disp32) +% Reg[EBX].i = 0x10; // source +% Reg[EAX].i = 0x61; // dest +== 0x01 # code segment +# op ModR/M SIB displacement immediate + 01 98 ff ff ff ff # add EBX to *(EAX-1) +# ModR/M in binary: 10 (indirect+disp32 mode) 011 (src EBX) 000 (dest EAX) +== 0x60 # data segment +01 00 00 00 # 1 ++run: add EBX to r/m32 ++run: effective address is initially 0x61 (EAX) ++run: effective address is 0x60 (after adding disp32) ++run: storing 0x00000011 |