diff options
Diffstat (limited to 'subx/apps/factorial.subx')
| -rw-r--r-- | subx/apps/factorial.subx | 126 |
1 files changed, 63 insertions, 63 deletions
diff --git a/subx/apps/factorial.subx b/subx/apps/factorial.subx index 43a61dcf..1e0191d1 100644 --- a/subx/apps/factorial.subx +++ b/subx/apps/factorial.subx @@ -15,94 +15,94 @@ # When running tests the exit status doesn't mean anything. Yet. == code -# 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: - # prolog - 89/copy 3/mod/direct 5/rm32/EBP . . . 4/r32/ESP . . # copy ESP to EBP - # if (argc > 1) - 81 7/subop/compare 1/mod/*+disp8 4/rm32/sib 5/base/EBP 4/index/none . . 0/disp8 1/imm32 # compare *EBP - 7e/jump-if-lesser-or-equal $run-main/disp8 - # and if (argv[1] == "test") + # prolog + 89/copy 3/mod/direct 5/rm32/EBP . . . 4/r32/ESP . . # copy ESP to EBP + # if (argc > 1) + 81 7/subop/compare 1/mod/*+disp8 4/rm32/sib 5/base/EBP 4/index/none . . 0/disp8 1/imm32 # compare *EBP + 7e/jump-if-lesser-or-equal $run-main/disp8 + # and if (argv[1] == "test") # push args - 68/push "test"/imm32 - ff 6/subop/push 1/mod/*+disp8 4/rm32/sib 5/base/EBP 4/index/none . . 0x8/disp8 . # push *(EBP+8) + 68/push "test"/imm32 + ff 6/subop/push 1/mod/*+disp8 4/rm32/sib 5/base/EBP 4/index/none . . 0x8/disp8 . # push *(EBP+8) # call - e8/call kernel-string-equal/disp32 + e8/call kernel-string-equal/disp32 # discard args - 81 0/subop/add 3/mod/direct 4/rm32/ESP . . . . . 8/imm32 # add to ESP + 81 0/subop/add 3/mod/direct 4/rm32/ESP . . . . . 8/imm32 # add to ESP # check result - 3d/compare-EAX 1/imm32 - 75/jump-if-not-equal $run-main/disp8 - # then return run-tests() - e8/call run-tests/disp32 - 8b/copy 0/mod/indirect 5/rm32/.disp32 . . 0/r32/EAX Num-test-failures/disp32 # copy *Num-test-failures to EAX - eb/jump $main:end/disp8 # where EAX will get copied to EBX - # else EAX = factorial(5) + 3d/compare-EAX 1/imm32 + 75/jump-if-not-equal $run-main/disp8 + # then return run-tests() + e8/call run-tests/disp32 + 8b/copy 0/mod/indirect 5/rm32/.disp32 . . 0/r32/EAX Num-test-failures/disp32 # copy *Num-test-failures to EAX + eb/jump $main:end/disp8 # where EAX will get copied to EBX + # else EAX = factorial(5) $run-main: # push args - 68/push 5/imm32 + 68/push 5/imm32 # call - e8/call factorial/disp32 + e8/call factorial/disp32 # discard args - 81 0/subop/add 3/mod/direct 4/rm32/ESP . . . . . 4/imm32 # add to ESP + 81 0/subop/add 3/mod/direct 4/rm32/ESP . . . . . 4/imm32 # add to ESP $main:end: - # exit(EAX) - 89/copy 3/mod/direct 3/rm32/EBX . . . 0/r32/EAX . . # copy EAX to EBX - b8/copy-to-EAX 1/imm32 - cd/syscall 0x80/imm8 + # exit(EAX) + 89/copy 3/mod/direct 3/rm32/EBX . . . 0/r32/EAX . . # copy EAX to EBX + b8/copy-to-EAX 1/imm32 + cd/syscall 0x80/imm8 # factorial(n) factorial: - # prolog - 55/push-EBP - 89/copy 3/mod/direct 5/rm32/EBP . . . 4/r32/ESP . . # copy ESP to EBP - 53/push-EBX - # initialize EAX to 1 (base case) - b8/copy-to-EAX 1/imm32 - # if (n <= 1) jump exit - 81 7/subop/compare 1/mod/*+disp8 4/rm32/sib 5/base/EBP 4/index/none . . 8/disp8 1/imm32 # compare *(EBP+8) - 7e/jump-if-<= $factorial:end/disp8 - # EBX = n-1 - 8b/copy 1/mod/*+disp8 4/rm32/sib 5/base/EBP 4/index/none 3/r32/EBX 8/disp8 . # copy *(EBP+8) to EBX - 81 5/subop/subtract 3/mod/direct 3/rm32/EBX . . . . . 1/imm32 # subtract from EBX - # EAX = factorial(n-1) + # prolog + 55/push-EBP + 89/copy 3/mod/direct 5/rm32/EBP . . . 4/r32/ESP . . # copy ESP to EBP + 53/push-EBX + # initialize EAX to 1 (base case) + b8/copy-to-EAX 1/imm32 + # if (n <= 1) jump exit + 81 7/subop/compare 1/mod/*+disp8 4/rm32/sib 5/base/EBP 4/index/none . . 8/disp8 1/imm32 # compare *(EBP+8) + 7e/jump-if-<= $factorial:end/disp8 + # EBX = n-1 + 8b/copy 1/mod/*+disp8 4/rm32/sib 5/base/EBP 4/index/none 3/r32/EBX 8/disp8 . # copy *(EBP+8) to EBX + 81 5/subop/subtract 3/mod/direct 3/rm32/EBX . . . . . 1/imm32 # subtract from EBX + # EAX = factorial(n-1) # push args - 53/push-EBX + 53/push-EBX # call - e8/call factorial/disp32 + e8/call factorial/disp32 # discard args - 81 0/subop/add 3/mod/direct 4/rm32/ESP . . . . . 4/imm32 # add to ESP - # return n * factorial(n-1) - f7 4/subop/multiply 1/mod/*+disp8 4/rm32/sib 5/base/EBP 4/index/none 8/disp8 . # multiply *(EBP+8) into EAX - # TODO: check for overflow + 81 0/subop/add 3/mod/direct 4/rm32/ESP . . . . . 4/imm32 # add to ESP + # return n * factorial(n-1) + f7 4/subop/multiply 1/mod/*+disp8 4/rm32/sib 5/base/EBP 4/index/none 8/disp8 . # multiply *(EBP+8) into EAX + # TODO: check for overflow $factorial:end: - # epilog - 5b/pop-to-EBX - 89/copy 3/mod/direct 4/rm32/ESP . . . 5/r32/EBP . . # copy EBP to ESP - 5d/pop-to-EBP - c3/return + # epilog + 5b/pop-to-EBX + 89/copy 3/mod/direct 4/rm32/ESP . . . 5/r32/EBP . . # copy EBP to ESP + 5d/pop-to-EBP + c3/return test-factorial: - # factorial(5) + # factorial(5) # push args - 68/push 5/imm32 + 68/push 5/imm32 # call - e8/call factorial/disp32 + e8/call factorial/disp32 # discard args - 81 0/subop/add 3/mod/direct 4/rm32/ESP . . . . . 4/imm32 # add to ESP - # check-ints-equal(EAX, 120, failure message) + 81 0/subop/add 3/mod/direct 4/rm32/ESP . . . . . 4/imm32 # add to ESP + # check-ints-equal(EAX, 120, failure message) # push args - 68/push "F - test-factorial"/imm32 - 68/push 0x78/imm32/expected-120 - 50/push-EAX + 68/push "F - test-factorial"/imm32 + 68/push 0x78/imm32/expected-120 + 50/push-EAX # call - e8/call check-ints-equal/disp32 + e8/call check-ints-equal/disp32 # discard args - 81 0/subop/add 3/mod/direct 4/rm32/ESP . . . . . 0xc/imm32 # add to ESP - # end - c3/return + 81 0/subop/add 3/mod/direct 4/rm32/ESP . . . . . 0xc/imm32 # add to ESP + # end + c3/return # vim:nowrap:textwidth=0 |