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| author | Kartik Agaram <vc@akkartik.com> | 2019-05-20 01:44:06 -0700 |
|---|---|---|
| committer | Kartik Agaram <vc@akkartik.com> | 2019-05-20 01:44:06 -0700 |
| commit | 52daf0722f7f4ad9d3f29e3cbbbaddde066f49f3 (patch) | |
| tree | dac2a82e0b7148f2f215dee77c013b7a6fb329a2 /html/subx/053new-segment.subx.html | |
| parent | cfea67e9a00419c4493699c0ac8691d9bbb0ceca (diff) | |
| download | mu-52daf0722f7f4ad9d3f29e3cbbbaddde066f49f3.tar.gz | |
5211
Update syntax-highlighted renderings after a _long_ time.
Diffstat (limited to 'html/subx/053new-segment.subx.html')
| -rw-r--r-- | html/subx/053new-segment.subx.html | 153 |
1 files changed, 90 insertions, 63 deletions
diff --git a/html/subx/053new-segment.subx.html b/html/subx/053new-segment.subx.html index d2aa0b40..91bccce0 100644 --- a/html/subx/053new-segment.subx.html +++ b/html/subx/053new-segment.subx.html @@ -58,69 +58,96 @@ if ('onhashchange' in window) { <body onload='JumpToLine();'> <a href='https://github.com/akkartik/mu/blob/master/subx/053new-segment.subx'>https://github.com/akkartik/mu/blob/master/subx/053new-segment.subx</a> <pre id='vimCodeElement'> -<span id="L1" class="LineNr"> 1 </span><span class="subxComment"># Create a new segment (for data) using mmap().</span> -<span id="L2" class="LineNr"> 2 </span> -<span id="L3" class="LineNr"> 3 </span>== code -<span id="L4" class="LineNr"> 4 </span><span class="subxComment"># instruction effective address register displacement immediate</span> -<span id="L5" class="LineNr"> 5 </span><span class="subxS1Comment"># . op subop mod rm32 base index scale r32</span> -<span id="L6" class="LineNr"> 6 </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> -<span id="L7" class="LineNr"> 7 </span> -<span id="L8" class="LineNr"> 8 </span><span class="SpecialChar">Entry</span>: <span class="subxComment"># manual test</span> -<span id="L9" class="LineNr"> 9 </span> <span class="subxComment"># EAX = new-segment(0x1000)</span> -<span id="L10" class="LineNr">10 </span> <span class="subxS2Comment"># . . push args</span> -<span id="L11" class="LineNr">11 </span> 68/push 0x1000/imm32 -<span id="L12" class="LineNr">12 </span> <span class="subxS2Comment"># . . call</span> -<span id="L13" class="LineNr">13 </span> e8/call <a href='053new-segment.subx.html#L25'>new-segment</a>/disp32 -<span id="L14" class="LineNr">14 </span> <span class="subxS2Comment"># . . discard args</span> -<span id="L15" class="LineNr">15 </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="L16" class="LineNr">16 </span> -<span id="L17" class="LineNr">17 </span> <span class="subxComment"># write to *EAX to check that we have access to the newly-allocated segment</span> -<span id="L18" class="LineNr">18 </span> c7 0/subop/copy 0/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> 0x34/imm32 <span class="subxComment"># copy to *EAX</span> -<span id="L19" class="LineNr">19 </span> -<span id="L20" class="LineNr">20 </span> <span class="subxComment"># syscall(exit, EAX)</span> -<span id="L21" class="LineNr">21 </span> 89/copy 3/mod/direct 3/rm32/EBX <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 EBX</span> -<span id="L22" class="LineNr">22 </span> b8/copy-to-EAX 1/imm32/exit -<span id="L23" class="LineNr">23 </span> cd/syscall 0x80/imm8 -<span id="L24" class="LineNr">24 </span> -<span id="L25" class="LineNr">25 </span><span class="subxFunction">new-segment</span>: <span class="subxComment"># len : int -> address</span> -<span id="L26" class="LineNr">26 </span> <span class="subxS1Comment"># . prolog</span> -<span id="L27" class="LineNr">27 </span> 55/push-EBP -<span id="L28" class="LineNr">28 </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="L29" class="LineNr">29 </span> 53/push-EBX -<span id="L30" class="LineNr">30 </span> <span class="subxComment"># copy len to _mmap-new-segment->len</span> -<span id="L31" class="LineNr">31 </span> <span class="subxComment"># TODO: compute _mmap-new-segment+4 before runtime</span> -<span id="L32" class="LineNr">32 </span> 8b/copy 1/mod/*+disp8 5/rm32/EBP <span class="Normal"> . </span> <span class="Normal"> . </span> <span class="Normal"> . </span> 0/r32/EAX 8/disp8 <span class="Normal"> . </span> <span class="subxComment"># copy *(EBP+8) to EAX</span> -<span id="L33" class="LineNr">33 </span> bb/copy-to-EBX <a href='053new-segment.subx.html#L49'>_mmap-new-segment</a>/imm32 -<span id="L34" class="LineNr">34 </span> 89/copy 1/mod/*+disp8 3/rm32/EBX <span class="Normal"> . </span> <span class="Normal"> . </span> <span class="Normal"> . </span> 0/r32/EAX 4/disp8 <span class="Normal"> . </span> <span class="subxComment"># copy EAX to *(EBX+4)</span> -<span id="L35" class="LineNr">35 </span> <span class="subxComment"># mmap(_mmap-new-segment)</span> -<span id="L36" class="LineNr">36 </span> bb/copy-to-EBX <a href='053new-segment.subx.html#L49'>_mmap-new-segment</a>/imm32 -<span id="L37" class="LineNr">37 </span> b8/copy-to-EAX 0x5a/imm32/mmap -<span id="L38" class="LineNr">38 </span> cd/syscall 0x80/imm8 -<span id="L39" class="LineNr">39 </span><span class="Constant">$new-segment:end</span>: -<span id="L40" class="LineNr">40 </span> <span class="subxS1Comment"># . epilog</span> -<span id="L41" class="LineNr">41 </span> 5b/pop-to-EBX -<span id="L42" class="LineNr">42 </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="L43" class="LineNr">43 </span> 5d/pop-to-EBP -<span id="L44" class="LineNr">44 </span> c3/return -<span id="L45" class="LineNr">45 </span> -<span id="L46" class="LineNr">46 </span>== data -<span id="L47" class="LineNr">47 </span> -<span id="L48" class="LineNr">48 </span><span class="subxComment"># various constants used here were found in the Linux sources (search for file mman-common.h)</span> -<span id="L49" class="LineNr">49 </span><span class="subxMinorFunction">_mmap-new-segment</span>: <span class="subxComment"># type mmap_arg_struct</span> -<span id="L50" class="LineNr">50 </span> <span class="subxComment"># addr</span> -<span id="L51" class="LineNr">51 </span> 0/imm32 -<span id="L52" class="LineNr">52 </span> <span class="subxComment"># len</span> -<span id="L53" class="LineNr">53 </span> 0/imm32 -<span id="L54" class="LineNr">54 </span> <span class="subxComment"># protection flags</span> -<span id="L55" class="LineNr">55 </span> 3/imm32 <span class="subxComment"># PROT_READ | PROT_WRITE</span> -<span id="L56" class="LineNr">56 </span> <span class="subxComment"># sharing flags</span> -<span id="L57" class="LineNr">57 </span> 0x22/imm32 <span class="subxComment"># MAP_PRIVATE | MAP_ANONYMOUS</span> -<span id="L58" class="LineNr">58 </span> <span class="subxComment"># fd</span> -<span id="L59" class="LineNr">59 </span> -1/imm32 <span class="subxComment"># since MAP_ANONYMOUS is specified</span> -<span id="L60" class="LineNr">60 </span> <span class="subxComment"># offset</span> -<span id="L61" class="LineNr">61 </span> 0/imm32 <span class="subxComment"># since MAP_ANONYMOUS is specified</span> -<span id="L62" class="LineNr">62 </span> -<span id="L63" class="LineNr">63 </span><span class="subxS2Comment"># . . vim:nowrap:textwidth=0</span> +<span id="L1" class="LineNr"> 1 </span><span class="subxComment"># Create a new segment (pool of memory for allocating chunks from) in the form</span> +<span id="L2" class="LineNr"> 2 </span><span class="subxComment"># of an *allocation descriptor* that can be passed to the memory allocator</span> +<span id="L3" class="LineNr"> 3 </span><span class="subxComment"># (defined in a later layer).</span> +<span id="L4" class="LineNr"> 4 </span><span class="subxComment">#</span> +<span id="L5" class="LineNr"> 5 </span><span class="subxComment"># Currently an allocation descriptor consists of just the bounds of the pool of</span> +<span id="L6" class="LineNr"> 6 </span><span class="subxComment"># available memory:</span> +<span id="L7" class="LineNr"> 7 </span><span class="subxComment">#</span> +<span id="L8" class="LineNr"> 8 </span><span class="subxComment"># curr : address</span> +<span id="L9" class="LineNr"> 9 </span><span class="subxComment"># end : address</span> +<span id="L10" class="LineNr">10 </span><span class="subxComment">#</span> +<span id="L11" class="LineNr">11 </span><span class="subxComment"># This isn't enough information to reclaim individual allocations. We can't</span> +<span id="L12" class="LineNr">12 </span><span class="subxComment"># support arbitrary reclamation yet.</span> +<span id="L13" class="LineNr">13 </span> +<span id="L14" class="LineNr">14 </span>== code +<span id="L15" class="LineNr">15 </span><span class="subxComment"># instruction effective address register displacement immediate</span> +<span id="L16" class="LineNr">16 </span><span class="subxS1Comment"># . op subop mod rm32 base index scale r32</span> +<span id="L17" class="LineNr">17 </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> +<span id="L18" class="LineNr">18 </span> +<span id="L19" class="LineNr">19 </span><span class="SpecialChar">Entry</span>: <span class="subxComment"># manual test</span> +<span id="L20" class="LineNr">20 </span> <span class="subxComment"># var ad/ECX : (address allocation-descriptor) = {0, 0}</span> +<span id="L21" class="LineNr">21 </span> 68/push 0/imm32/limit +<span id="L22" class="LineNr">22 </span> 68/push 0/imm32/curr +<span id="L23" class="LineNr">23 </span> 89/copy 3/mod/direct 1/rm32/ECX <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 ECX</span> +<span id="L24" class="LineNr">24 </span> <span class="subxComment"># new-segment(0x1000, ad)</span> +<span id="L25" class="LineNr">25 </span> <span class="subxS2Comment"># . . push args</span> +<span id="L26" class="LineNr">26 </span> 51/push-ECX +<span id="L27" class="LineNr">27 </span> 68/push 0x1000/imm32 +<span id="L28" class="LineNr">28 </span> <span class="subxS2Comment"># . . call</span> +<span id="L29" class="LineNr">29 </span> e8/call <a href='053new-segment.subx.html#L41'>new-segment</a>/disp32 +<span id="L30" class="LineNr">30 </span> <span class="subxS2Comment"># . . discard args</span> +<span id="L31" class="LineNr">31 </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="L32" class="LineNr">32 </span> <span class="subxComment"># EAX = ad->curr</span> +<span id="L33" class="LineNr">33 </span> 8b/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 *ECX to EAX</span> +<span id="L34" class="LineNr">34 </span> <span class="subxComment"># write to *EAX to check that we have access to the newly-allocated segment</span> +<span id="L35" class="LineNr">35 </span> c7 0/subop/copy 0/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> 0x34/imm32 <span class="subxComment"># copy to *EAX</span> +<span id="L36" class="LineNr">36 </span> <span class="subxComment"># syscall(exit, EAX)</span> +<span id="L37" class="LineNr">37 </span> 89/copy 3/mod/direct 3/rm32/EBX <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 EBX</span> +<span id="L38" class="LineNr">38 </span> b8/copy-to-EAX 1/imm32/exit +<span id="L39" class="LineNr">39 </span> cd/syscall 0x80/imm8 +<span id="L40" class="LineNr">40 </span> +<span id="L41" class="LineNr">41 </span><span class="subxFunction">new-segment</span>: <span class="subxComment"># len : int, ad : (address allocation-descriptor)</span> +<span id="L42" class="LineNr">42 </span> <span class="subxS1Comment"># . prolog</span> +<span id="L43" class="LineNr">43 </span> 55/push-EBP +<span id="L44" class="LineNr">44 </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="L45" class="LineNr">45 </span> <span class="subxS1Comment"># . save registers</span> +<span id="L46" class="LineNr">46 </span> 50/push-EAX +<span id="L47" class="LineNr">47 </span> 53/push-EBX +<span id="L48" class="LineNr">48 </span> <span class="subxComment"># copy len to _mmap-new-segment->len</span> +<span id="L49" class="LineNr">49 </span> 8b/copy 1/mod/*+disp8 5/rm32/EBP <span class="Normal"> . </span> <span class="Normal"> . </span> <span class="Normal"> . </span> 0/r32/EAX 8/disp8 <span class="Normal"> . </span> <span class="subxComment"># copy *(EBP+8) to EAX</span> +<span id="L50" class="LineNr">50 </span> 89/copy 0/mod/indirect 5/rm32/.disp32 <span class="Normal"> . </span> <span class="Normal"> . </span> 0/r32/EAX <a href='053new-segment.subx.html#L75'>_mmap-new-segment</a>:len/disp32 <span class="subxComment"># copy EAX to *_mmap-new-segment:len</span> +<span id="L51" class="LineNr">51 </span> <span class="subxComment"># mmap(_mmap-new-segment)</span> +<span id="L52" class="LineNr">52 </span> bb/copy-to-EBX <a href='053new-segment.subx.html#L75'>_mmap-new-segment</a>/imm32 +<span id="L53" class="LineNr">53 </span> b8/copy-to-EAX 0x5a/imm32/mmap +<span id="L54" class="LineNr">54 </span> cd/syscall 0x80/imm8 +<span id="L55" class="LineNr">55 </span> <span class="subxComment"># copy {EAX, EAX+len} to *ad</span> +<span id="L56" class="LineNr">56 </span> <span class="subxS1Comment"># . EBX = ad</span> +<span id="L57" class="LineNr">57 </span> 8b/copy 1/mod/*+disp8 5/rm32/EBP <span class="Normal"> . </span> <span class="Normal"> . </span> <span class="Normal"> . </span> 3/r32/EBX 0xc/disp8 <span class="Normal"> . </span> <span class="subxComment"># copy *(EBP+12) to EBX</span> +<span id="L58" class="LineNr">58 </span> <span class="subxS1Comment"># . *EBX = EAX</span> +<span id="L59" class="LineNr">59 </span> 89/copy 0/mod/indirect 3/rm32/EBX <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 *EBX</span> +<span id="L60" class="LineNr">60 </span> <span class="subxS1Comment"># . *(EBX+4) = EAX+len</span> +<span id="L61" class="LineNr">61 </span> 03/add 1/mod/*+disp8 5/rm32/EBP <span class="Normal"> . </span> <span class="Normal"> . </span> <span class="Normal"> . </span> 0/r32/EAX 8/disp8 <span class="Normal"> . </span> <span class="subxComment"># add *(EBP+8) to EAX</span> +<span id="L62" class="LineNr">62 </span> 89/copy 1/mod/*+disp8 3/rm32/EBX <span class="Normal"> . </span> <span class="Normal"> . </span> <span class="Normal"> . </span> 0/r32/EAX 4/disp8 <span class="Normal"> . </span> <span class="subxComment"># copy EAX to *(EBX+4)</span> +<span id="L63" class="LineNr">63 </span><span class="Constant">$new-segment:end</span>: +<span id="L64" class="LineNr">64 </span> <span class="subxS1Comment"># . restore registers</span> +<span id="L65" class="LineNr">65 </span> 5b/pop-to-EBX +<span id="L66" class="LineNr">66 </span> 58/pop-to-EAX +<span id="L67" class="LineNr">67 </span> <span class="subxS1Comment"># . epilog</span> +<span id="L68" class="LineNr">68 </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="L69" class="LineNr">69 </span> 5d/pop-to-EBP +<span id="L70" class="LineNr">70 </span> c3/return +<span id="L71" class="LineNr">71 </span> +<span id="L72" class="LineNr">72 </span>== data +<span id="L73" class="LineNr">73 </span> +<span id="L74" class="LineNr">74 </span><span class="subxComment"># various constants used here were found in the Linux sources (search for file mman-common.h)</span> +<span id="L75" class="LineNr">75 </span><span class="subxMinorFunction">_mmap-new-segment</span>: <span class="subxComment"># type mmap_arg_struct</span> +<span id="L76" class="LineNr">76 </span> <span class="subxComment"># addr</span> +<span id="L77" class="LineNr">77 </span> 0/imm32 +<span id="L78" class="LineNr">78 </span><span class="subxMinorFunction">_mmap-new-segment:len</span>: +<span id="L79" class="LineNr">79 </span> <span class="subxComment"># len</span> +<span id="L80" class="LineNr">80 </span> 0/imm32 +<span id="L81" class="LineNr">81 </span> <span class="subxComment"># protection flags</span> +<span id="L82" class="LineNr">82 </span> 3/imm32 <span class="subxComment"># PROT_READ | PROT_WRITE</span> +<span id="L83" class="LineNr">83 </span> <span class="subxComment"># sharing flags</span> +<span id="L84" class="LineNr">84 </span> 0x22/imm32 <span class="subxComment"># MAP_PRIVATE | MAP_ANONYMOUS</span> +<span id="L85" class="LineNr">85 </span> <span class="subxComment"># fd</span> +<span id="L86" class="LineNr">86 </span> -1/imm32 <span class="subxComment"># since MAP_ANONYMOUS is specified</span> +<span id="L87" class="LineNr">87 </span> <span class="subxComment"># offset</span> +<span id="L88" class="LineNr">88 </span> 0/imm32 <span class="subxComment"># since MAP_ANONYMOUS is specified</span> +<span id="L89" class="LineNr">89 </span> +<span id="L90" class="LineNr">90 </span><span class="subxS2Comment"># . . vim:nowrap:textwidth=0</span> </pre> </body> </html> |