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< title > Mu - linux/110stop.subx< / title >
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< a href = 'https://github.com/akkartik/mu/blob/main/linux/110stop.subx' > https://github.com/akkartik/mu/blob/main/linux/110stop.subx< / a >
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< pre id = 'vimCodeElement' >
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< span id = "L1" class = "LineNr" > 1 < / span > < span class = "subxComment" > # stop: dependency-injected wrapper around the exit() syscall< / span >
< span id = "L2" class = "LineNr" > 2 < / span > < span class = "subxComment" > #< / span >
< span id = "L3" class = "LineNr" > 3 < / span > < span class = "subxComment" > # We'd like to be able to write tests for functions that call exit(), and to< / span >
< span id = "L4" class = "LineNr" > 4 < / span > < span class = "subxComment" > # make assertions about whether they exit() or not in a given situation. To< / span >
< span id = "L5" class = "LineNr" > 5 < / span > < span class = "subxComment" > # achieve this we'll call exit() via a smarter wrapper called 'stop'.< / span >
< span id = "L6" class = "LineNr" > 6 < / span > < span class = "subxComment" > #< / span >
< span id = "L7" class = "LineNr" > 7 < / span > < span class = "subxComment" > # In the context of a test, calling a function X that calls 'stop' (directly< / span >
< span id = "L8" class = "LineNr" > 8 < / span > < span class = "subxComment" > # or through further intervening calls) will unwind the stack until X returns,< / span >
< span id = "L9" class = "LineNr" > 9 < / span > < span class = "subxComment" > # so that we can say check any further assertions after the execution of X. To< / span >
< span id = "L10" class = "LineNr" > 10 < / span > < span class = "subxComment" > # achieve this end, we'll pass the return address of X as a 'target' argument< / span >
< span id = "L11" class = "LineNr" > 11 < / span > < span class = "subxComment" > # into X, plumbing it through to 'stop'. When 'stop' gets a non-null target it< / span >
< span id = "L12" class = "LineNr" > 12 < / span > < span class = "subxComment" > # unwinds the stack until the target. If it gets a null target it calls< / span >
< span id = "L13" class = "LineNr" > 13 < / span > < span class = "subxComment" > # exit().< / span >
< span id = "L14" class = "LineNr" > 14 < / span > < span class = "subxComment" > #< / span >
< span id = "L15" class = "LineNr" > 15 < / span > < span class = "subxComment" > # We'd also like to get the exit status out of 'stop', so we'll combine the< / span >
< span id = "L16" class = "LineNr" > 16 < / span > < span class = "subxComment" > # input target with an output status parameter into a type called 'exit-descriptor'.< / span >
< span id = "L17" class = "LineNr" > 17 < / span > < span class = "subxComment" > #< / span >
< span id = "L18" class = "LineNr" > 18 < / span > < span class = "subxComment" > # So the exit-descriptor looks like this:< / span >
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< span id = "L19" class = "LineNr" > 19 < / span > < span class = "subxComment" > # target: address # return address for 'stop' to unwind to< / span >
< span id = "L20" class = "LineNr" > 20 < / span > < span class = "subxComment" > # value: int # exit status stop was called with< / span >
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< span id = "L21" class = "LineNr" > 21 < / span > < span class = "subxComment" > #< / span >
< span id = "L22" class = "LineNr" > 22 < / span > < span class = "subxComment" > # 'stop' thus takes two parameters: an exit-descriptor and the exit status.< / span >
< span id = "L23" class = "LineNr" > 23 < / span > < span class = "subxComment" > #< / span >
< span id = "L24" class = "LineNr" > 24 < / span > < span class = "subxComment" > # 'stop' won't bother cleaning up any other processor state besides the stack,< / span >
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< span id = "L25" class = "LineNr" > 25 < / span > < span class = "subxComment" > # such as registers. Only esp will have a well-defined value after 'stop'< / span >
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< span id = "L26" class = "LineNr" > 26 < / span > < span class = "subxComment" > # returns. (This is a poor man's setjmp/longjmp, if you know what that is.)< / span >
< span id = "L27" class = "LineNr" > 27 < / span > < span class = "subxComment" > #< / span >
< span id = "L28" class = "LineNr" > 28 < / span > < span class = "subxComment" > # Before you can call any function that may call 'stop', you need to pass in an< / span >
< span id = "L29" class = "LineNr" > 29 < / span > < span class = "subxComment" > # exit-descriptor to it. To create an exit-descriptor use 'tailor-exit-descriptor'< / span >
< span id = "L30" class = "LineNr" > 30 < / span > < span class = "subxComment" > # below. It's not the most pleasant abstraction in the world.< / span >
< span id = "L31" class = "LineNr" > 31 < / span > < span class = "subxComment" > #< / span >
< span id = "L32" class = "LineNr" > 32 < / span > < span class = "subxComment" > # An exit-descriptor's target is its input, computed during 'tailor-exit-descriptor'.< / span >
< span id = "L33" class = "LineNr" > 33 < / span > < span class = "subxComment" > # Its value is its output, computed during stop and available to the test.< / span >
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< span id = "L34" class = "LineNr" > 34 < / span >
< span id = "L35" class = "LineNr" > 35 < / span > == code
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< span id = "L36" class = "LineNr" > 36 < / span > < span class = "subxComment" > # instruction effective address register displacement immediate< / span >
< span id = "L37" class = "LineNr" > 37 < / span > < span class = "subxS1Comment" > # . op subop mod rm32 base index scale r32< / span >
< span id = "L38" class = "LineNr" > 38 < / span > < span class = "subxS1Comment" > # . 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< / span >
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< span id = "L39" class = "LineNr" > 39 < / span >
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< span id = "L40" class = "LineNr" > 40 < / span > < span class = "subxComment" > # Configure an exit-descriptor for a call pushing 'nbytes' bytes of args to< / span >
< span id = "L41" class = "LineNr" > 41 < / span > < span class = "subxComment" > # the stack.< / span >
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< span id = "L42" class = "LineNr" > 42 < / span > < span class = "subxComment" > # Ugly that we need to know the size of args. Don't allocate variables between< / span >
< span id = "L43" class = "LineNr" > 43 < / span > < span class = "subxComment" > # tailor-exit-descriptor and the call it's for.< / span >
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< span id = "L44" class = "LineNr" > 44 < / span > < span class = "subxFunction" > tailor-exit-descriptor< / span > : < span class = "subxComment" > # ed: (addr exit-descriptor), nbytes: int< / span >
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< span id = "L45" class = "LineNr" > 45 < / span > < span class = "subxS1Comment" > # . prologue< / span >
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< span id = "L46" class = "LineNr" > 46 < / span > 55/push-ebp
< span id = "L47" class = "LineNr" > 47 < / span > 89/copy 3/mod/direct 5/rm32/ebp < span class = "Normal" > . < / span > < span class = "Normal" > . < / span > < span class = "Normal" > . < / span > 4/r32/esp < span class = "Normal" > . < / span > < span class = "Normal" > . < / span > < span class = "subxComment" > # copy esp to ebp< / span >
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< span id = "L48" class = "LineNr" > 48 < / span > < span class = "subxS1Comment" > # . save registers< / span >
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< span id = "L49" class = "LineNr" > 49 < / span > 50/push-eax
< span id = "L50" class = "LineNr" > 50 < / span > 51/push-ecx
< span id = "L51" class = "LineNr" > 51 < / span > < span class = "subxComment" > # eax = nbytes< / span >
< span id = "L52" class = "LineNr" > 52 < / span > 8b/copy 1/mod/*+disp8 5/rm32/ebp < span class = "Normal" > . < / span > < span class = "Normal" > . < / span > < span class = "Normal" > . < / span > 0/r32/eax 0xc/disp8 < span class = "Normal" > . < / span > < span class = "subxComment" > # copy *(ebp+12) to eax< / span >
< span id = "L53" class = "LineNr" > 53 < / span > < span class = "subxComment" > # Let X be the value of esp in the caller, before the call to tailor-exit-descriptor.< / span >
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< span id = "L54" class = "LineNr" > 54 < / span > < span class = "subxComment" > # The return address for a call in the caller's body will be at:< / span >
< span id = "L55" class = "LineNr" > 55 < / span > < span class = "subxComment" > # X-8 if the caller takes 4 bytes of args for the exit-descriptor (add 4 bytes for the return address)< / span >
< span id = "L56" class = "LineNr" > 56 < / span > < span class = "subxComment" > # X-12 if the caller takes 8 bytes of args< / span >
< span id = "L57" class = "LineNr" > 57 < / span > < span class = "subxComment" > # ..and so on< / span >
< span id = "L58" class = "LineNr" > 58 < / span > < span class = "subxComment" > # That's the value we need to return: X-nbytes-4< / span >
< span id = "L59" class = "LineNr" > 59 < / span > < span class = "subxComment" > #< / span >
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< span id = "L60" class = "LineNr" > 60 < / span > < span class = "subxComment" > # However, we also need to account for the perturbance to esp caused by the< / span >
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< span id = "L61" class = "LineNr" > 61 < / span > < span class = "subxComment" > # call to tailor-exit-descriptor. It pushes 8 bytes of args followed by 4< / span >
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< span id = "L62" class = "LineNr" > 62 < / span > < span class = "subxComment" > # bytes for the return address and 4 bytes to push ebp above.< / span >
< span id = "L63" class = "LineNr" > 63 < / span > < span class = "subxComment" > # So ebp at this point is X-16.< / span >
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< span id = "L64" class = "LineNr" > 64 < / span > < span class = "subxComment" > #< / span >
< span id = "L65" class = "LineNr" > 65 < / span > < span class = "subxComment" > # So the return address for the next call in the caller is:< / span >
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< span id = "L66" class = "LineNr" > 66 < / span > < span class = "subxComment" > # ebp+8 if the caller takes 4 bytes of args< / span >
< span id = "L67" class = "LineNr" > 67 < / span > < span class = "subxComment" > # ebp+4 if the caller takes 8 bytes of args< / span >
< span id = "L68" class = "LineNr" > 68 < / span > < span class = "subxComment" > # ebp if the caller takes 12 bytes of args< / span >
< span id = "L69" class = "LineNr" > 69 < / span > < span class = "subxComment" > # ebp-4 if the caller takes 16 bytes of args< / span >
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< span id = "L70" class = "LineNr" > 70 < / span > < span class = "subxComment" > # ..and so on< / span >
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< span id = "L71" class = "LineNr" > 71 < / span > < span class = "subxComment" > # That's ebp+12-nbytes.< / span >
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< span id = "L72" class = "LineNr" > 72 < / span > < span class = "subxComment" > # option 1: 6 + 3 bytes< / span >
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< span id = "L73" class = "LineNr" > 73 < / span > < span class = "CommentedCode" > #? 2d/subtract 3/mod/direct 0/rm32/eax . . . . . 8/imm32 # subtract from eax< / span >
< span id = "L74" class = "LineNr" > 74 < / span > < span class = "CommentedCode" > #? 8d/copy-address 0/mod/indirect 4/rm32/sib 5/base/ebp 0/index/eax . 0/r32/eax . . # copy ebp+eax to eax< / span >
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< span id = "L75" class = "LineNr" > 75 < / span > < span class = "subxComment" > # option 2: 2 + 4 bytes< / span >
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< span id = "L76" class = "LineNr" > 76 < / span > f7 3/subop/negate 3/mod/direct 0/rm32/eax < span class = "Normal" > . < / span > < span class = "Normal" > . < / span > < span class = "Normal" > . < / span > < span class = "Normal" > . < / span > < span class = "Normal" > . < / span > < span class = "Normal" > . < / span > < span class = "subxComment" > # negate eax< / span >
< span id = "L77" class = "LineNr" > 77 < / span > 8d/copy-address 1/mod/*+disp8 4/rm32/sib 5/base/ebp 0/index/eax < span class = "Normal" > . < / span > 0/r32/eax 0xc/disp8 < span class = "Normal" > . < / span > < span class = "subxComment" > # copy ebp+eax+12 to eax< / span >
< span id = "L78" class = "LineNr" > 78 < / span > < span class = "subxComment" > # copy eax to ed-> target< / span >
< span id = "L79" class = "LineNr" > 79 < / span > 8b/copy 1/mod/*+disp8 5/rm32/ebp < span class = "Normal" > . < / span > < span class = "Normal" > . < / span > < span class = "Normal" > . < / span > 1/r32/ecx 8/disp8 < span class = "Normal" > . < / span > < span class = "subxComment" > # copy *(ebp+8) to ecx< / span >
< span id = "L80" class = "LineNr" > 80 < / span > 89/copy 0/mod/indirect 1/rm32/ecx < span class = "Normal" > . < / span > < span class = "Normal" > . < / span > < span class = "Normal" > . < / span > 0/r32/eax < span class = "Normal" > . < / span > < span class = "Normal" > . < / span > < span class = "subxComment" > # copy eax to *ecx< / span >
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< span id = "L81" class = "LineNr" > 81 < / span > < span class = "subxComment" > # initialize ed-> value< / span >
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< span id = "L82" class = "LineNr" > 82 < / span > c7 0/subop/copy 1/mod/*+disp8 1/rm32/ecx < span class = "Normal" > . < / span > < span class = "Normal" > . < / span > < span class = "Normal" > . < / span > < span class = "Normal" > . < / span > 4/disp8 0/imm32 < span class = "subxComment" > # copy to *(ecx+4)< / span >
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< span id = "L83" class = "LineNr" > 83 < / span > < span class = "Constant" > $tailor-exit-descriptor:end< / span > :
< span id = "L84" class = "LineNr" > 84 < / span > < span class = "subxS1Comment" > # . restore registers< / span >
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< span id = "L85" class = "LineNr" > 85 < / span > 59/pop-to-ecx
< span id = "L86" class = "LineNr" > 86 < / span > 58/pop-to-eax
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< span id = "L87" class = "LineNr" > 87 < / span > < span class = "subxS1Comment" > # . epilogue< / span >
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< span id = "L88" class = "LineNr" > 88 < / span > 89/copy 3/mod/direct 4/rm32/esp < span class = "Normal" > . < / span > < span class = "Normal" > . < / span > < span class = "Normal" > . < / span > 5/r32/ebp < span class = "Normal" > . < / span > < span class = "Normal" > . < / span > < span class = "subxComment" > # copy ebp to esp< / span >
< span id = "L89" class = "LineNr" > 89 < / span > 5d/pop-to-ebp
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< span id = "L90" class = "LineNr" > 90 < / span > c3/return
< span id = "L91" class = "LineNr" > 91 < / span >
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< span id = "L92" class = "LineNr" > 92 < / span > < span class = "subxFunction" > stop< / span > : < span class = "subxComment" > # ed: (addr exit-descriptor), value: int< / span >
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< span id = "L93" class = "LineNr" > 93 < / span > < span class = "subxComment" > # no prologue; one way or another, we're going to clobber registers< / span >
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< span id = "L94" class = "LineNr" > 94 < / span > < span class = "subxComment" > # eax = ed< / span >
< span id = "L95" class = "LineNr" > 95 < / span > 8b/copy 1/mod/*+disp8 4/rm32/sib 4/base/esp 4/index/none < span class = "Normal" > . < / span > 0/r32/eax 4/disp8 < span class = "Normal" > . < / span > < span class = "subxComment" > # copy *(esp+4) to eax< / span >
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< span id = "L96" class = "LineNr" > 96 < / span > < span class = "subxComment" > # if (ed == 0) really exit< / span >
< span id = "L97" class = "LineNr" > 97 < / span > 3d/compare-eax-and 0/imm32
< span id = "L98" class = "LineNr" > 98 < / span > 74/jump-if-= $stop:real/disp8
< span id = "L99" class = "LineNr" > 99 < / span > < span class = "subxComment" > # if (ed-> target == 0) really exit< / span >
< span id = "L100" class = "LineNr" > 100 < / span > 81 7/subop/compare 0/mod/indirect 0/rm32/eax < span class = "Normal" > . < / span > < span class = "Normal" > . < / span > < span class = "Normal" > . < / span > < span class = "Normal" > . < / span > < span class = "Normal" > . < / span > 0/imm32 < span class = "subxComment" > # compare *eax< / span >
< span id = "L101" class = "LineNr" > 101 < / span > 74/jump-if-= $stop:real/disp8
< span id = "L102" class = "LineNr" > 102 < / span > < span class = "Constant" > $stop:fake< / span > :
< span id = "L103" class = "LineNr" > 103 < / span > < span class = "subxComment" > # ed-> value = value+1< / span >
< span id = "L104" class = "LineNr" > 104 < / span > 8b/copy 1/mod/*+disp8 4/rm32/sib 4/base/esp 4/index/none < span class = "Normal" > . < / span > 1/r32/ecx 8/disp8 < span class = "Normal" > . < / span > < span class = "subxComment" > # copy *(esp+8) to ecx< / span >
< span id = "L105" class = "LineNr" > 105 < / span > 41/increment-ecx
< span id = "L106" class = "LineNr" > 106 < / span > 89/copy 1/mod/*+disp8 0/rm32/eax < span class = "Normal" > . < / span > < span class = "Normal" > . < / span > < span class = "Normal" > . < / span > 1/r32/ecx 4/disp8 < span class = "Normal" > . < / span > < span class = "subxComment" > # copy ecx to *(eax+4)< / span >
< span id = "L107" class = "LineNr" > 107 < / span > < span class = "subxComment" > # perform a non-local jump to ed-> target< / span >
< span id = "L108" class = "LineNr" > 108 < / span > 8b/copy 0/mod/indirect 0/rm32/eax < span class = "Normal" > . < / span > < span class = "Normal" > . < / span > < span class = "Normal" > . < / span > 4/r32/esp < span class = "Normal" > . < / span > < span class = "Normal" > . < / span > < span class = "subxComment" > # copy *eax to esp< / span >
< span id = "L109" class = "LineNr" > 109 < / span > < span class = "Constant" > $stop:end1< / span > :
< span id = "L110" class = "LineNr" > 110 < / span > < span class = "subxComment" > # never gets here< / span >
< span id = "L111" class = "LineNr" > 111 < / span > c3/return < span class = "subxComment" > # doesn't return to caller< / span >
< span id = "L112" class = "LineNr" > 112 < / span > < span class = "Constant" > $stop:real< / span > :
< span id = "L113" class = "LineNr" > 113 < / span > < span class = "subxS1Comment" > # . syscall(exit, value)< / span >
< span id = "L114" class = "LineNr" > 114 < / span > 8b/copy 1/mod/*+disp8 4/rm32/sib 4/base/esp 4/index/none < span class = "Normal" > . < / span > 3/r32/ebx 8/disp8 < span class = "Normal" > . < / span > < span class = "subxComment" > # copy *(esp+8) to ebx< / span >
2021-03-24 00:31:08 +00:00
< span id = "L115" class = "LineNr" > 115 < / span > e8/call < a href = '000init.subx.html#L18' > syscall_exit< / a > /disp32
2020-06-12 14:57:27 +00:00
< span id = "L116" class = "LineNr" > 116 < / span > < span class = "Constant" > $stop:end2< / span > :
< span id = "L117" class = "LineNr" > 117 < / span > < span class = "subxComment" > # never gets here< / span >
< span id = "L118" class = "LineNr" > 118 < / span > c3/return < span class = "subxComment" > # doesn't return to caller< / span >
< span id = "L119" class = "LineNr" > 119 < / span >
< span id = "L120" class = "LineNr" > 120 < / span > < span class = "subxTest" > test-stop-skips-returns-on-exit< / span > :
< span id = "L121" class = "LineNr" > 121 < / span > < span class = "subxComment" > # This looks like the standard prologue, but is here for different reasons.< / span >
< span id = "L122" class = "LineNr" > 122 < / span > < span class = "subxComment" > # A function calling 'stop' can't rely on ebp persisting past the call.< / span >
< span id = "L123" class = "LineNr" > 123 < / span > < span class = "subxComment" > #< / span >
< span id = "L124" class = "LineNr" > 124 < / span > < span class = "subxComment" > # Use ebp here as a stable base to refer to locals and arguments from in the< / span >
< span id = "L125" class = "LineNr" > 125 < / span > < span class = "subxComment" > # presence of push/pop/call instructions.< / span >
< span id = "L126" class = "LineNr" > 126 < / span > < span class = "subxComment" > # *Don't* use ebp as a way to restore esp.< / span >
< span id = "L127" class = "LineNr" > 127 < / span > 55/push-ebp
< span id = "L128" class = "LineNr" > 128 < / span > 89/copy 3/mod/direct 5/rm32/ebp < span class = "Normal" > . < / span > < span class = "Normal" > . < / span > < span class = "Normal" > . < / span > 4/r32/esp < span class = "Normal" > . < / span > < span class = "Normal" > . < / span > < span class = "subxComment" > # copy esp to ebp< / span >
< span id = "L129" class = "LineNr" > 129 < / span > < span class = "subxComment" > # Make room for an exit descriptor on the stack. That's almost always the< / span >
< span id = "L130" class = "LineNr" > 130 < / span > < span class = "subxComment" > # right place for it, available only as long as it's legal to use. Once this< / span >
< span id = "L131" class = "LineNr" > 131 < / span > < span class = "subxComment" > # containing function returns we'll need a new exit descriptor.< / span >
< span id = "L132" class = "LineNr" > 132 < / span > < span class = "subxComment" > # var ed/eax: exit-descriptor< / span >
< span id = "L133" class = "LineNr" > 133 < / span > 68/push 0/imm32
< span id = "L134" class = "LineNr" > 134 < / span > 68/push 0/imm32
< span id = "L135" class = "LineNr" > 135 < / span > 89/copy 3/mod/direct 0/rm32/eax < span class = "Normal" > . < / span > < span class = "Normal" > . < / span > < span class = "Normal" > . < / span > 4/r32/esp < span class = "Normal" > . < / span > < span class = "Normal" > . < / span > < span class = "subxComment" > # copy esp to eax< / span >
< span id = "L136" class = "LineNr" > 136 < / span > < span class = "subxComment" > # Size the exit-descriptor precisely for the next call below, to _test-stop-1.< / span >
< span id = "L137" class = "LineNr" > 137 < / span > < span class = "subxComment" > # tailor-exit-descriptor(ed, 4)< / span >
< span id = "L138" class = "LineNr" > 138 < / span > < span class = "subxS2Comment" > # . . push args< / span >
< span id = "L139" class = "LineNr" > 139 < / span > 68/push 4/imm32/nbytes-of-args-for-_test-stop-1
< span id = "L140" class = "LineNr" > 140 < / span > 50/push-eax
< span id = "L141" class = "LineNr" > 141 < / span > < span class = "subxS2Comment" > # . . call< / span >
2020-07-11 06:44:10 +00:00
< span id = "L142" class = "LineNr" > 142 < / span > e8/call < a href = '110stop.subx.html#L44' > tailor-exit-descriptor< / a > /disp32
2020-06-12 14:57:27 +00:00
< span id = "L143" class = "LineNr" > 143 < / span > < span class = "subxS2Comment" > # . . discard args< / span >
< span id = "L144" class = "LineNr" > 144 < / span > 81 0/subop/add 3/mod/direct 4/rm32/esp < span class = "Normal" > . < / span > < span class = "Normal" > . < / span > < span class = "Normal" > . < / span > < span class = "Normal" > . < / span > < span class = "Normal" > . < / span > 8/imm32 < span class = "subxComment" > # add to esp< / span >
< span id = "L145" class = "LineNr" > 145 < / span > < span class = "subxS1Comment" > # . _test-stop-1(ed)< / span >
< span id = "L146" class = "LineNr" > 146 < / span > < span class = "subxS2Comment" > # . . push args< / span >
< span id = "L147" class = "LineNr" > 147 < / span > 50/push-eax
< span id = "L148" class = "LineNr" > 148 < / span > < span class = "subxS2Comment" > # . . call< / span >
2020-07-11 06:44:10 +00:00
< span id = "L149" class = "LineNr" > 149 < / span > e8/call < a href = '110stop.subx.html#L170' > _test-stop-1< / a > /disp32
2020-06-12 14:57:27 +00:00
< span id = "L150" class = "LineNr" > 150 < / span > < span class = "subxComment" > # registers except esp may be clobbered at this point< / span >
< span id = "L151" class = "LineNr" > 151 < / span > < span class = "subxComment" > # restore args< / span >
< span id = "L152" class = "LineNr" > 152 < / span > 58/pop-to-eax
< span id = "L153" class = "LineNr" > 153 < / span > < span class = "subxComment" > # check that _test-stop-1 tried to call exit(1)< / span >
< span id = "L154" class = "LineNr" > 154 < / span > < span class = "subxS1Comment" > # . check-ints-equal(ed-> value, 2, msg) # i.e. stop was called with value 1< / span >
< span id = "L155" class = "LineNr" > 155 < / span > < span class = "subxS2Comment" > # . . push args< / span >
< span id = "L156" class = "LineNr" > 156 < / span > 68/push < span class = "Constant" > " F - test-stop-skips-returns-on-exit" < / span > /imm32
< span id = "L157" class = "LineNr" > 157 < / span > 68/push 2/imm32
< span id = "L158" class = "LineNr" > 158 < / span > < span class = "subxS2Comment" > # . . push ed-> value< / span >
< span id = "L159" class = "LineNr" > 159 < / span > ff 6/subop/push 1/mod/*+disp8 0/rm32/eax < span class = "Normal" > . < / span > < span class = "Normal" > . < / span > < span class = "Normal" > . < / span > < span class = "Normal" > . < / span > 4/disp8 < span class = "Normal" > . < / span > < span class = "subxComment" > # push *(eax+4)< / span >
< span id = "L160" class = "LineNr" > 160 < / span > < span class = "subxS2Comment" > # . . call< / span >
2020-07-11 06:44:10 +00:00
< span id = "L161" class = "LineNr" > 161 < / span > e8/call < a href = '102test.subx.html#L23' > check-ints-equal< / a > /disp32
2020-06-12 14:57:27 +00:00
< span id = "L162" class = "LineNr" > 162 < / span > < span class = "subxS2Comment" > # . . discard args< / span >
< span id = "L163" class = "LineNr" > 163 < / span > 81 0/subop/add 3/mod/direct 4/rm32/esp < span class = "Normal" > . < / span > < span class = "Normal" > . < / span > < span class = "Normal" > . < / span > < span class = "Normal" > . < / span > < span class = "Normal" > . < / span > 0xc/imm32 < span class = "subxComment" > # add to esp< / span >
< span id = "L164" class = "LineNr" > 164 < / span > < span class = "subxS1Comment" > # . epilogue< / span >
< span id = "L165" class = "LineNr" > 165 < / span > < span class = "subxComment" > # don't restore esp from ebp; manually reclaim locals< / span >
< span id = "L166" class = "LineNr" > 166 < / span > 81 0/subop/add 3/mod/direct 4/rm32/esp < span class = "Normal" > . < / span > < span class = "Normal" > . < / span > < span class = "Normal" > . < / span > < span class = "Normal" > . < / span > < span class = "Normal" > . < / span > 8/imm32 < span class = "subxComment" > # add to esp< / span >
< span id = "L167" class = "LineNr" > 167 < / span > 5d/pop-to-ebp
< span id = "L168" class = "LineNr" > 168 < / span > c3/return
< span id = "L169" class = "LineNr" > 169 < / span >
< span id = "L170" class = "LineNr" > 170 < / span > < span class = "subxMinorFunction" > _test-stop-1< / span > : < span class = "subxComment" > # ed: (addr exit-descriptor)< / span >
< span id = "L171" class = "LineNr" > 171 < / span > < span class = "subxS1Comment" > # . prologue< / span >
< span id = "L172" class = "LineNr" > 172 < / span > 55/push-ebp
< span id = "L173" class = "LineNr" > 173 < / span > 89/copy 3/mod/direct 5/rm32/ebp < span class = "Normal" > . < / span > < span class = "Normal" > . < / span > < span class = "Normal" > . < / span > 4/r32/esp < span class = "Normal" > . < / span > < span class = "Normal" > . < / span > < span class = "subxComment" > # copy esp to ebp< / span >
< span id = "L174" class = "LineNr" > 174 < / span > < span class = "subxComment" > # _test-stop-2(ed)< / span >
< span id = "L175" class = "LineNr" > 175 < / span > < span class = "subxS2Comment" > # . . push args< / span >
< span id = "L176" class = "LineNr" > 176 < / span > ff 6/subop/push 1/mod/*+disp8 5/rm32/ebp < span class = "Normal" > . < / span > < span class = "Normal" > . < / span > < span class = "Normal" > . < / span > < span class = "Normal" > . < / span > 8/disp8 < span class = "Normal" > . < / span > < span class = "subxComment" > # push *(ebp+8)< / span >
< span id = "L177" class = "LineNr" > 177 < / span > < span class = "subxS2Comment" > # . . call< / span >
2020-07-11 06:44:10 +00:00
< span id = "L178" class = "LineNr" > 178 < / span > e8/call < a href = '110stop.subx.html#L197' > _test-stop-2< / a > /disp32
2020-06-12 14:57:27 +00:00
< span id = "L179" class = "LineNr" > 179 < / span > < span class = "subxComment" > # should never get past this point< / span >
< span id = "L180" class = "LineNr" > 180 < / span > < span class = "Constant" > $_test-stop-1:dead-end< / span > :
< span id = "L181" class = "LineNr" > 181 < / span > < span class = "subxS2Comment" > # . . discard args< / span >
< span id = "L182" class = "LineNr" > 182 < / span > 81 0/subop/add 3/mod/direct 4/rm32/esp < span class = "Normal" > . < / span > < span class = "Normal" > . < / span > < span class = "Normal" > . < / span > < span class = "Normal" > . < / span > < span class = "Normal" > . < / span > 4/imm32 < span class = "subxComment" > # add to esp< / span >
< span id = "L183" class = "LineNr" > 183 < / span > < span class = "subxComment" > # signal test failed: check-ints-equal(1, 0, msg)< / span >
< span id = "L184" class = "LineNr" > 184 < / span > < span class = "subxS2Comment" > # . . push args< / span >
< span id = "L185" class = "LineNr" > 185 < / span > 68/push < span class = "Constant" > " F - test-stop-skips-returns-on-exit" < / span > /imm32
< span id = "L186" class = "LineNr" > 186 < / span > 68/push 0/imm32
< span id = "L187" class = "LineNr" > 187 < / span > 68/push 1/imm32
< span id = "L188" class = "LineNr" > 188 < / span > < span class = "subxS2Comment" > # . . call< / span >
2020-07-11 06:44:10 +00:00
< span id = "L189" class = "LineNr" > 189 < / span > e8/call < a href = '102test.subx.html#L23' > check-ints-equal< / a > /disp32
2020-06-12 14:57:27 +00:00
< span id = "L190" class = "LineNr" > 190 < / span > < span class = "subxS2Comment" > # . . discard args< / span >
< span id = "L191" class = "LineNr" > 191 < / span > 81 0/subop/add 3/mod/direct 4/rm32/esp < span class = "Normal" > . < / span > < span class = "Normal" > . < / span > < span class = "Normal" > . < / span > < span class = "Normal" > . < / span > < span class = "Normal" > . < / span > 0xc/imm32 < span class = "subxComment" > # add to esp< / span >
< span id = "L192" class = "LineNr" > 192 < / span > < span class = "subxS1Comment" > # . epilogue< / span >
< span id = "L193" class = "LineNr" > 193 < / span > 89/copy 3/mod/direct 4/rm32/esp < span class = "Normal" > . < / span > < span class = "Normal" > . < / span > < span class = "Normal" > . < / span > 5/r32/ebp < span class = "Normal" > . < / span > < span class = "Normal" > . < / span > < span class = "subxComment" > # copy ebp to esp< / span >
< span id = "L194" class = "LineNr" > 194 < / span > 5d/pop-to-ebp
< span id = "L195" class = "LineNr" > 195 < / span > c3/return
< span id = "L196" class = "LineNr" > 196 < / span >
< span id = "L197" class = "LineNr" > 197 < / span > < span class = "subxMinorFunction" > _test-stop-2< / span > : < span class = "subxComment" > # ed: (addr exit-descriptor)< / span >
< span id = "L198" class = "LineNr" > 198 < / span > < span class = "subxS1Comment" > # . prologue< / span >
< span id = "L199" class = "LineNr" > 199 < / span > 55/push-ebp
< span id = "L200" class = "LineNr" > 200 < / span > 89/copy 3/mod/direct 5/rm32/ebp < span class = "Normal" > . < / span > < span class = "Normal" > . < / span > < span class = "Normal" > . < / span > 4/r32/esp < span class = "Normal" > . < / span > < span class = "Normal" > . < / span > < span class = "subxComment" > # copy esp to ebp< / span >
< span id = "L201" class = "LineNr" > 201 < / span > < span class = "subxS1Comment" > # . stop(ed, 1)< / span >
< span id = "L202" class = "LineNr" > 202 < / span > < span class = "subxS2Comment" > # . . push args< / span >
< span id = "L203" class = "LineNr" > 203 < / span > 68/push 1/imm32
< span id = "L204" class = "LineNr" > 204 < / span > ff 6/subop/push 1/mod/*+disp8 5/rm32/ebp < span class = "Normal" > . < / span > < span class = "Normal" > . < / span > < span class = "Normal" > . < / span > < span class = "Normal" > . < / span > 8/disp8 < span class = "Normal" > . < / span > < span class = "subxComment" > # push *(ebp+8)< / span >
< span id = "L205" class = "LineNr" > 205 < / span > < span class = "subxS2Comment" > # . . call< / span >
2020-07-11 06:44:10 +00:00
< span id = "L206" class = "LineNr" > 206 < / span > e8/call < a href = '110stop.subx.html#L92' > stop< / a > /disp32
2020-06-12 14:57:27 +00:00
< span id = "L207" class = "LineNr" > 207 < / span > < span class = "subxComment" > # should never get past this point< / span >
< span id = "L208" class = "LineNr" > 208 < / span > < span class = "Constant" > $_test-stop-2:dead-end< / span > :
< span id = "L209" class = "LineNr" > 209 < / span > < span class = "subxS1Comment" > # . epilogue< / span >
< span id = "L210" class = "LineNr" > 210 < / span > 89/copy 3/mod/direct 4/rm32/esp < span class = "Normal" > . < / span > < span class = "Normal" > . < / span > < span class = "Normal" > . < / span > 5/r32/ebp < span class = "Normal" > . < / span > < span class = "Normal" > . < / span > < span class = "subxComment" > # copy ebp to esp< / span >
< span id = "L211" class = "LineNr" > 211 < / span > 5d/pop-to-ebp
< span id = "L212" class = "LineNr" > 212 < / span > c3/return
< span id = "L213" class = "LineNr" > 213 < / span >
< span id = "L214" class = "LineNr" > 214 < / span > < span class = "subxS2Comment" > # . . vim: nowrap:textwidth=0< / span >
2018-10-25 06:05:58 +00:00
< / pre >
< / body >
< / html >
<!-- vim: set foldmethod=manual : -->