diff options
author | Kartik Agaram <vc@akkartik.com> | 2018-08-03 23:23:39 -0700 |
---|---|---|
committer | Kartik Agaram <vc@akkartik.com> | 2018-08-03 23:23:39 -0700 |
commit | 12adb3da8a8979c207b2e7fd17bdb05bacefeb44 (patch) | |
tree | 12c1a96ffe7feb8b41613e0b2cead1c3919db8d9 | |
parent | 85173b622021de062706df81947df7ae2300b654 (diff) | |
download | mu-12adb3da8a8979c207b2e7fd17bdb05bacefeb44.tar.gz |
4467
-rw-r--r-- | subx/022check_instruction.cc | 16 | ||||
-rw-r--r-- | subx/024pack_operands.cc | 32 | ||||
-rw-r--r-- | subx/026labels.cc | 20 | ||||
-rw-r--r-- | subx/ex1.2.subx | 12 | ||||
-rw-r--r-- | subx/ex2.subx | 14 | ||||
-rw-r--r-- | subx/ex3.subx | 24 | ||||
-rw-r--r-- | subx/ex4.subx | 30 | ||||
-rw-r--r-- | subx/ex5.subx | 36 | ||||
-rw-r--r-- | subx/ex6.subx | 22 | ||||
-rw-r--r-- | subx/ex7.subx | 56 |
10 files changed, 131 insertions, 131 deletions
diff --git a/subx/022check_instruction.cc b/subx/022check_instruction.cc index 1e0bf7de..97dc8140 100644 --- a/subx/022check_instruction.cc +++ b/subx/022check_instruction.cc @@ -55,10 +55,10 @@ cerr << " instructions\n"; :(scenario check_missing_imm8_operand) % Hide_errors = true; == 0x1 -# instruction effective address operand displacement immediate -# op subop mod rm32 base index scale r32 -# 1-3 bytes 3 bits 2 bits 3 bits 3 bits 3 bits 2 bits 2 bits 0/1/2/4 bytes 0/1/2/4 bytes - cd # int ?? +# instruction effective address operand displacement immediate +# op subop mod rm32 base index scale r32 +# 1-3 bytes 3 bits 2 bits 3 bits 3 bits 3 bits 2 bits 2 bits 0/1/2/4 bytes 0/1/2/4 bytes + cd # int ?? +error: 'cd' (software interrupt): missing imm8 operand :(before "End One-time Setup") @@ -584,10 +584,10 @@ void check_operands_f3(const line& /*unused*/) { :(scenario check_missing_disp16_operand) % Hide_errors = true; == 0x1 -# instruction effective address operand displacement immediate -# op subop mod rm32 base index scale r32 -# 1-3 bytes 3 bits 2 bits 3 bits 3 bits 3 bits 2 bits 2 bits 0/1/2/4 bytes 0/1/2/4 bytes - 0f 84 # jmp if ZF to ?? +# instruction effective address operand displacement immediate +# op subop mod rm32 base index scale r32 +# 1-3 bytes 3 bits 2 bits 3 bits 3 bits 3 bits 2 bits 2 bits 0/1/2/4 bytes 0/1/2/4 bytes + 0f 84 # jmp if ZF to ?? +error: '0f 84' (jump disp16 bytes away if ZF is set): missing disp16 operand :(before "End Globals") diff --git a/subx/024pack_operands.cc b/subx/024pack_operands.cc index 26573395..f8effd16 100644 --- a/subx/024pack_operands.cc +++ b/subx/024pack_operands.cc @@ -3,10 +3,10 @@ :(scenario pack_immediate_constants) == 0x1 -# instruction effective address operand displacement immediate -# op subop mod rm32 base index scale r32 -# 1-3 bytes 3 bits 2 bits 3 bits 3 bits 3 bits 2 bits 2 bits 0/1/2/4 bytes 0/1/2/4 bytes - bb 0x2a/imm32 # copy 42 to EBX +# instruction effective address operand displacement immediate +# op subop mod rm32 base index scale r32 +# 1-3 bytes 3 bits 2 bits 3 bits 3 bits 3 bits 2 bits 2 bits 0/1/2/4 bytes 0/1/2/4 bytes + bb 0x2a/imm32 # copy 42 to EBX +transform: packing instruction 'bb 0x2a/imm32' +transform: instruction after packing: 'bb 2a 00 00 00' +run: copy imm32 0x0000002a to EBX @@ -28,10 +28,10 @@ :(scenario pack_modrm_imm32) == 0x1 -# instruction effective address operand displacement immediate -# op subop mod rm32 base index scale r32 -# 1-3 bytes 3 bits 2 bits 3 bits 3 bits 3 bits 2 bits 2 bits 0/1/2/4 bytes 0/1/2/4 bytes - 81 0/add/subop 3/mod/direct 3/ebx/rm32 1/imm32 # add 1 to EBX +# instruction effective address operand displacement immediate +# op subop mod rm32 base index scale r32 +# 1-3 bytes 3 bits 2 bits 3 bits 3 bits 3 bits 2 bits 2 bits 0/1/2/4 bytes 0/1/2/4 bytes + 81 0/add/subop 3/mod/direct 3/ebx/rm32 1/imm32 # add 1 to EBX +transform: packing instruction '81 0/add/subop 3/mod/direct 3/ebx/rm32 1/imm32' +transform: instruction after packing: '81 c3 01 00 00 00' @@ -183,10 +183,10 @@ string to_string(const vector<word>& in) { :(scenario pack_immediate_constants_hex) == 0x1 -# instruction effective address operand displacement immediate -# op subop mod rm32 base index scale r32 -# 1-3 bytes 3 bits 2 bits 3 bits 3 bits 3 bits 2 bits 2 bits 0/1/2/4 bytes 0/1/2/4 bytes - bb 0x2a/imm32 # copy 42 to EBX +# instruction effective address operand displacement immediate +# op subop mod rm32 base index scale r32 +# 1-3 bytes 3 bits 2 bits 3 bits 3 bits 3 bits 2 bits 2 bits 0/1/2/4 bytes 0/1/2/4 bytes + bb 0x2a/imm32 # copy 42 to EBX +transform: packing instruction 'bb 0x2a/imm32' +transform: instruction after packing: 'bb 2a 00 00 00' +run: copy imm32 0x0000002a to EBX @@ -194,10 +194,10 @@ string to_string(const vector<word>& in) { :(scenarios transform) :(scenario pack_silently_ignores_non_hex) == 0x1 -# instruction effective address operand displacement immediate -# op subop mod rm32 base index scale r32 -# 1-3 bytes 3 bits 2 bits 3 bits 3 bits 3 bits 2 bits 2 bits 0/1/2/4 bytes 0/1/2/4 bytes - bb foo/imm32 # copy foo to EBX +# instruction effective address operand displacement immediate +# op subop mod rm32 base index scale r32 +# 1-3 bytes 3 bits 2 bits 3 bits 3 bits 3 bits 2 bits 2 bits 0/1/2/4 bytes 0/1/2/4 bytes + bb foo/imm32 # copy foo to EBX +transform: packing instruction 'bb foo/imm32' # no change (we're just not printing metadata to the trace) +transform: instruction after packing: 'bb foo' diff --git a/subx/026labels.cc b/subx/026labels.cc index db6091d6..78190c6d 100644 --- a/subx/026labels.cc +++ b/subx/026labels.cc @@ -4,11 +4,11 @@ :(scenarios transform) :(scenario map_label) == 0x1 - # instruction effective address operand displacement immediate - # op subop mod rm32 base index scale r32 - # 1-3 bytes 3 bits 2 bits 3 bits 3 bits 3 bits 2 bits 2 bits 0/1/2/4 bytes 0/1/2/4 bytes + # instruction effective address operand displacement immediate + # op subop mod rm32 base index scale r32 + # 1-3 bytes 3 bits 2 bits 3 bits 3 bits 3 bits 2 bits 2 bits 0/1/2/4 bytes 0/1/2/4 bytes loop: - 05 0x0d0c0b0a/imm32 # add to EAX + 05 0x0d0c0b0a/imm32 # add to EAX +transform: label 'loop' is at address 1 :(before "End One-time Setup") @@ -138,18 +138,18 @@ string data_to_string(const line& inst) { :(scenario multiple_labels_at) == 0x1 - # instruction effective address operand displacement immediate - # op subop mod rm32 base index scale r32 - # 1-3 bytes 3 bits 2 bits 3 bits 3 bits 3 bits 2 bits 2 bits 0/1/2/4 bytes 0/1/2/4 bytes + # instruction effective address operand displacement immediate + # op subop mod rm32 base index scale r32 + # 1-3 bytes 3 bits 2 bits 3 bits 3 bits 3 bits 2 bits 2 bits 0/1/2/4 bytes 0/1/2/4 bytes # address 1 loop: loop2: # address 1 (labels take up no space) - 05 0x0d0c0b0a/imm32 # add to EAX + 05 0x0d0c0b0a/imm32 # add to EAX # address 6 - eb loop2/disp8 + eb loop2/disp8 # address 8 - eb loop3/disp8 + eb loop3/disp8 # address 10 loop3: +transform: label 'loop' is at address 1 diff --git a/subx/ex1.2.subx b/subx/ex1.2.subx index 844678b7..2652037a 100644 --- a/subx/ex1.2.subx +++ b/subx/ex1.2.subx @@ -9,12 +9,12 @@ # 42 == 0x08048054 # code segment, after leaving room for ELF header -# instruction effective address operand displacement immediate -# op subop mod rm32 base index scale r32 -# 1-3 bytes 3 bits 2 bits 3 bits 3 bits 3 bits 2 bits 2 bits 0/1/2/4 bytes 0/1/2/4 bytes - bb/copy 2a/imm32 # copy 42 to EBX +# instruction effective address operand displacement immediate +# op subop mod rm32 base index scale r32 +# 1-3 bytes 3 bits 2 bits 3 bits 3 bits 3 bits 2 bits 2 bits 0/1/2/4 bytes 0/1/2/4 bytes + bb/copy 2a/imm32 # copy 42 to EBX # exit(EBX) - b8/copy 1/imm32 # copy 1 to EAX - cd/syscall 0x80/imm8 # int 80h + b8/copy 1/imm32 # copy 1 to EAX + cd/syscall 0x80/imm8 # int 80h # vim:ft=subx diff --git a/subx/ex2.subx b/subx/ex2.subx index 20cee840..c63b7eb6 100644 --- a/subx/ex2.subx +++ b/subx/ex2.subx @@ -8,13 +8,13 @@ # 2 == 0x08048054 # code segment, after leaving room for ELF header -# instruction effective address operand displacement immediate -# op subop mod rm32 base index scale r32 -# 1-3 bytes 3 bits 2 bits 3 bits 3 bits 3 bits 2 bits 2 bits 0/1/2/4 bytes 0/1/2/4 bytes - bb/copy 1/imm32 # copy 1 to EBX - 81 0/subop/add 3/mod/direct 3/rm32/ebx 1/imm32 # add 1 to EBX +# instruction effective address operand displacement immediate +# op subop mod rm32 base index scale r32 +# 1-3 bytes 3 bits 2 bits 3 bits 3 bits 3 bits 2 bits 2 bits 0/1/2/4 bytes 0/1/2/4 bytes + bb/copy 1/imm32 # copy 1 to EBX + 81 0/subop/add 3/mod/direct 3/rm32/ebx 1/imm32 # add 1 to EBX # exit(EBX) - b8/copy 1/imm32 # copy 1 to EAX - cd/syscall 0x80/imm8 # int 80h + b8/copy 1/imm32 # copy 1 to EAX + cd/syscall 0x80/imm8 # int 80h # vim:ft=subx diff --git a/subx/ex3.subx b/subx/ex3.subx index 2ad61edd..eb66f1bf 100644 --- a/subx/ex3.subx +++ b/subx/ex3.subx @@ -8,28 +8,28 @@ # 55 == 0x08048054 # code segment, after leaving room for ELF header -# instruction effective address operand displacement immediate -# op subop mod rm32 base index scale r32 -# 1-3 bytes 3 bits 2 bits 3 bits 3 bits 3 bits 2 bits 2 bits 0/1/2/4 bytes 0/1/2/4 bytes +# instruction effective address operand displacement immediate +# op subop mod rm32 base index scale r32 +# 1-3 bytes 3 bits 2 bits 3 bits 3 bits 3 bits 2 bits 2 bits 0/1/2/4 bytes 0/1/2/4 bytes # result: EBX = 0 - bb/copy 0/imm32 # copy 0 to EBX + bb/copy 0/imm32 # copy 0 to EBX # counter: ECX = 1 - b9/copy 1/imm32 # copy 1 to ECX + b9/copy 1/imm32 # copy 1 to ECX loop: # while (counter <= 10) - 81 7/subop/compare 3/mod/direct 1/rm32/ecx 0xa/imm32 # compare ECX, 10/imm - 7f/jump-if exit/disp8 # jump-if-greater exit + 81 7/subop/compare 3/mod/direct 1/rm32/ecx 0xa/imm32 # compare ECX, 10/imm + 7f/jump-if exit/disp8 # jump-if-greater exit # result += counter - 01/add 3/mod/direct 3/rm32/ebx 1/r32/ecx # add ECX to EBX + 01/add 3/mod/direct 3/rm32/ebx 1/r32/ecx # add ECX to EBX # ++counter - 81 0/subop/add 3/mod/direct 1/rm32/ecx 1/imm32 # add 1 to ECX + 81 0/subop/add 3/mod/direct 1/rm32/ecx 1/imm32 # add 1 to ECX # loop - eb/jump loop/disp8 # jump loop + eb/jump loop/disp8 # jump loop exit: # exit(EBX) - b8/copy 1/imm32 # copy 1 to EAX - cd/syscall 0x80/imm8 # int 80h + b8/copy 1/imm32 # copy 1 to EAX + cd/syscall 0x80/imm8 # int 80h # vim:ft=subx:nowrap diff --git a/subx/ex4.subx b/subx/ex4.subx index 0d5f76a8..59dd14e1 100644 --- a/subx/ex4.subx +++ b/subx/ex4.subx @@ -5,35 +5,35 @@ # $ subx run ex4 == 0x08048074 # code segment, after leaving room for ELF header and segment headers -# instruction effective address operand displacement immediate -# op subop mod rm32 base index scale r32 -# 1-3 bytes 3 bits 2 bits 3 bits 3 bits 3 bits 2 bits 2 bits 0/1/2/4 bytes 0/1/2/4 bytes +# instruction effective address operand displacement immediate +# op subop mod rm32 base index scale r32 +# 1-3 bytes 3 bits 2 bits 3 bits 3 bits 3 bits 2 bits 2 bits 0/1/2/4 bytes 0/1/2/4 bytes ## read(stdin, x, 1) # fd = 0 (stdin) - bb/copy 0/imm32 # copy 0 to EBX + bb/copy 0/imm32 # copy 0 to EBX # initialize x (location to write result to) - b9/copy 0x080490a7/imm32 # copy to ECX + b9/copy 0x080490a7/imm32 # copy to ECX # size = 1 character - ba/copy 1/imm32 # copy 1 to EDX + ba/copy 1/imm32 # copy 1 to EDX # read(fd, x, size) - b8/copy 3/imm32 # copy 3 to EAX - cd/syscall 0x80/imm8 # int 80h + b8/copy 3/imm32 # copy 3 to EAX + cd/syscall 0x80/imm8 # int 80h ## write(stdout, x, 1) # fd = 1 (stdout) - bb/copy 1/imm32 # copy 1 to EBX + bb/copy 1/imm32 # copy 1 to EBX # initialize x (location to read from) - b9/copy 0x080490a7/imm32 # copy to ECX + b9/copy 0x080490a7/imm32 # copy to ECX # size = 1 character - ba/copy 1/imm32 # copy 1 to EDX + ba/copy 1/imm32 # copy 1 to EDX # write(fd, x, size) - b8/copy 4/imm32 # copy 4 to EAX - cd/syscall 0x80/imm8 # int 80h + b8/copy 4/imm32 # copy 4 to EAX + cd/syscall 0x80/imm8 # int 80h ## exit(EBX) - b8/copy 1/imm32 # copy 1 to EAX - cd/syscall 0x80/imm8 # int 80h + b8/copy 1/imm32 # copy 1 to EAX + cd/syscall 0x80/imm8 # int 80h == 0x080490a7 00 00 00 00 # space for read() to write to diff --git a/subx/ex5.subx b/subx/ex5.subx index bdbfe6f4..e4a2db81 100644 --- a/subx/ex5.subx +++ b/subx/ex5.subx @@ -5,41 +5,41 @@ # $ subx run ex5 == 0x08048054 # code segment, after leaving room for ELF header and segment headers -# instruction effective address operand displacement immediate -# op subop mod rm32 base index scale r32 -# 1-3 bytes 3 bits 2 bits 3 bits 3 bits 3 bits 2 bits 2 bits 0/1/2/4 bytes 0/1/2/4 bytes +# instruction effective address operand displacement immediate +# op subop mod rm32 base index scale r32 +# 1-3 bytes 3 bits 2 bits 3 bits 3 bits 3 bits 2 bits 2 bits 0/1/2/4 bytes 0/1/2/4 bytes ## function main # prolog - 55/push # push EBP - 89/copy 3/mod/direct 5/rm32/EBP 4/r32/ESP # copy ESP to EBP + 55/push # push EBP + 89/copy 3/mod/direct 5/rm32/EBP 4/r32/ESP # copy ESP to EBP # allocate x on the stack - 81 5/subop/subtract 3/mod/direct 4/rm32/ESP 4/imm32 # subtract 4 bytes from ESP + 81 5/subop/subtract 3/mod/direct 4/rm32/ESP 4/imm32 # subtract 4 bytes from ESP ## read(stdin, x, 1) # fd = 0 (stdin) - bb/copy 0/imm32 # copy 0 to EBX + bb/copy 0/imm32 # copy 0 to EBX # initialize x (location to write result to) - 89/copy 3/mod/direct 1/rm32/ECX 5/r32/EBP # copy EBP to ECX + 89/copy 3/mod/direct 1/rm32/ECX 5/r32/EBP # copy EBP to ECX # size = 1 character - ba/copy 1/imm32 # copy 1 to EDX + ba/copy 1/imm32 # copy 1 to EDX # read(fd, x, size) - b8/copy 3/imm32 # copy 3 to EAX - cd/syscall 0x80/imm8 # int 80h + b8/copy 3/imm32 # copy 3 to EAX + cd/syscall 0x80/imm8 # int 80h ## write(stdout, x, 1) # fd = 1 (stdout) - bb/copy 1/imm32 # copy 1 to EBX + bb/copy 1/imm32 # copy 1 to EBX # initialize x (location to read from) - 89/copy 3/mod/direct 1/rm32/ECX 5/r32/EBP # copy EBP to ECX + 89/copy 3/mod/direct 1/rm32/ECX 5/r32/EBP # copy EBP to ECX # size = 1 character - ba/copy 1/imm32 # copy 1 to EDX + ba/copy 1/imm32 # copy 1 to EDX # write(fd, x, size) - b8/copy 4/imm32 # copy 4 to EAX - cd/syscall 0x80/imm8 # int 80h + b8/copy 4/imm32 # copy 4 to EAX + cd/syscall 0x80/imm8 # int 80h ## exit(EBX) - b8/copy 1/imm32 # copy 1 to EAX - cd/syscall 0x80/imm8 # int 80h + b8/copy 1/imm32 # copy 1 to EAX + cd/syscall 0x80/imm8 # int 80h # vim:ft=subx:nowrap diff --git a/subx/ex6.subx b/subx/ex6.subx index 2c9555d8..8f4f6b40 100644 --- a/subx/ex6.subx +++ b/subx/ex6.subx @@ -6,25 +6,25 @@ # Hello, world! == 0x08048074 # code segment, after leaving room for ELF header and segment headers -# instruction effective address operand displacement immediate -# op subop mod rm32 base index scale r32 -# 1-3 bytes 3 bits 2 bits 3 bits 3 bits 3 bits 2 bits 2 bits 0/1/2/4 bytes 0/1/2/4 bytes +# instruction effective address operand displacement immediate +# op subop mod rm32 base index scale r32 +# 1-3 bytes 3 bits 2 bits 3 bits 3 bits 3 bits 2 bits 2 bits 0/1/2/4 bytes 0/1/2/4 bytes ## write(stdout, x, 1) # fd = 1 (stdout) - bb/copy 1/imm32 # copy 1 to EBX + bb/copy 1/imm32 # copy 1 to EBX # initialize x (location to write result to) - b9/copy 0x08049097/imm32 # copy to ECX + b9/copy 0x08049097/imm32 # copy to ECX # initialize size - ba/copy 0x08049093/imm32 # copy to EDX - 8b/copy 0/mod/indirect 2/rm32/edx 2/r32/edx # copy *EDX to EDX + ba/copy 0x08049093/imm32 # copy to EDX + 8b/copy 0/mod/indirect 2/rm32/edx 2/r32/edx # copy *EDX to EDX # write(fd, x, size) - b8/copy 4/imm32 # copy 4 to EAX - cd/syscall 0x80/imm8 # int 80h + b8/copy 4/imm32 # copy 4 to EAX + cd/syscall 0x80/imm8 # int 80h ## exit(EBX) - b8/copy 1/imm32 # copy 1 to EAX - cd/syscall 0x80/imm8 # int 80h + b8/copy 1/imm32 # copy 1 to EAX + cd/syscall 0x80/imm8 # int 80h == 0x08049093 # size of string diff --git a/subx/ex7.subx b/subx/ex7.subx index fab91b6a..4474e110 100644 --- a/subx/ex7.subx +++ b/subx/ex7.subx @@ -8,80 +8,80 @@ # 120 == 0x08048054 # code segment, after leaving room for ELF header -# instruction effective address operand displacement immediate -# op subop mod rm32 base index scale r32 -# 1-3 bytes 3 bits 2 bits 3 bits 3 bits 3 bits 2 bits 2 bits 0/1/2/4 bytes 0/1/2/4 bytes +# instruction effective address operand displacement immediate +# op subop mod rm32 base index scale r32 +# 1-3 bytes 3 bits 2 bits 3 bits 3 bits 3 bits 2 bits 2 bits 0/1/2/4 bytes 0/1/2/4 bytes # main: # prepare to make a call # 54 - 55/push # push EBP + 55/push # push EBP # 55 - 89/copy 3/mod/direct 5/rm32/EBP 4/r32/ESP # copy ESP to EBP + 89/copy 3/mod/direct 5/rm32/EBP 4/r32/ESP # copy ESP to EBP # 57 # factorial(5) - 68/push 5/imm32 # push 5 + 68/push 5/imm32 # push 5 # 5c - e8/call factorial/disp32 + e8/call factorial/disp32 # 61 # discard arg - 5a/pop # pop into EDX + 5a/pop # pop into EDX # 62 # clean up after call - 89/copy 3/mod/direct 4/rm32/ESP 5/r32/EBP # copy EBP to ESP + 89/copy 3/mod/direct 4/rm32/ESP 5/r32/EBP # copy EBP to ESP # 64 - 5d/pop # pop to EBP + 5d/pop # pop to EBP # exit(EAX) # 65 - 89/copy 3/mod/direct 3/rm32/EBX 0/r32/EAX # copy EAX to EBX + 89/copy 3/mod/direct 3/rm32/EBX 0/r32/EAX # copy EAX to EBX # 67 - b8/copy 1/imm32 # copy 1 to EAX + b8/copy 1/imm32 # copy 1 to EAX # 6c - cd/syscall 0x80/imm8 # int 80h + cd/syscall 0x80/imm8 # int 80h # factorial(n) # 6e factorial: # initialize n - 8b/copy 1/mod/*+disp8 4/rm32/sib 4/base/ESP 4/index/none 2/r32/EDX 4/disp8 # copy *(ESP+4) to EDX + 8b/copy 1/mod/*+disp8 4/rm32/sib 4/base/ESP 4/index/none 2/r32/EDX 4/disp8 # copy *(ESP+4) to EDX # 72 # initialize EAX to 1 (base case) - b8/copy 1/imm32 # copy 1 to EAX + b8/copy 1/imm32 # copy 1 to EAX # 77 # if (n <= 1) jump exit - 81 7/subop/compare 3/mod/direct 2/rm32/EDX 1/imm32 # compare EDX with 1 + 81 7/subop/compare 3/mod/direct 2/rm32/EDX 1/imm32 # compare EDX with 1 # 7d - 7e/jump-if factorial:exit/disp8 # jump if <= to exit + 7e/jump-if factorial:exit/disp8 # jump if <= to exit # 7f # EBX: n-1 - 89/copy 3/mod/direct 3/rm32/EBX 2/r32/EDX # copy EDX to EBX + 89/copy 3/mod/direct 3/rm32/EBX 2/r32/EDX # copy EDX to EBX # 81 - 81 5/subop/subtract 3/mod/direct 3/rm32/EBX 1/imm32 # subtract 1 from EBX + 81 5/subop/subtract 3/mod/direct 3/rm32/EBX 1/imm32 # subtract 1 from EBX # 87 # prepare call - 55/push # push EBP + 55/push # push EBP # 88 - 89/copy 3/mod/direct 5/rm32/EBP 4/r32/ESP # copy ESP to EBP + 89/copy 3/mod/direct 5/rm32/EBP 4/r32/ESP # copy ESP to EBP # EAX: factorial(n-1) # 8a - 53/push # push EBX + 53/push # push EBX # 8b - e8/call factorial/disp32 + e8/call factorial/disp32 # 90 # discard arg - 5e/pop # pop into ESI + 5e/pop # pop into ESI # 91 # clean up after call - 89/copy 3/mod/direct 4/rm32/ESP 5/r32/EBP # copy EBP to ESP + 89/copy 3/mod/direct 4/rm32/ESP 5/r32/EBP # copy EBP to ESP # 93 - 5d/pop # pop to EBP + 5d/pop # pop to EBP # 94 # refresh n - 8b/copy 1/mod/*+disp8 4/rm32/sib 4/base/ESP 4/index/none 2/r32/EDX 4/disp8 # copy *(ESP+4) to EDX + 8b/copy 1/mod/*+disp8 4/rm32/sib 4/base/ESP 4/index/none 2/r32/EDX 4/disp8 # copy *(ESP+4) to EDX # 98 # return n * factorial(n-1) - 0f af/multiply 3/mod/direct 2/rm32/EDX 0/r32/EAX # multiply EDX (n) into EAX (factorial(n-1)) + 0f af/multiply 3/mod/direct 2/rm32/EDX 0/r32/EAX # multiply EDX (n) into EAX (factorial(n-1)) # TODO: check for overflow # 9b factorial:exit: |