Mu - subx/077slurp.subx

From 6e1eeeebfb453fa7c871869c19375ce60fbd7413 Mon Sep 17 00:00:00 2001 From: Kartik Agaram Date: Sat, 27 Jul 2019 16:01:55 -0700 Subject: 5485 - promote SubX to top-level --- html/077slurp.subx.html | 224 ++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 224 insertions(+) create mode 100644 html/077slurp.subx.html (limited to 'html/077slurp.subx.html') diff --git a/html/077slurp.subx.html b/html/077slurp.subx.html new file mode 100644 index 00000000..c1accb25 --- /dev/null +++ b/html/077slurp.subx.html @@ -0,0 +1,224 @@ + + + + +Mu - subx/077slurp.subx + + + + + + + + + + +https://github.com/akkartik/mu/blob/master/subx/077slurp.subx +
+  1 == code
+  2 #   instruction                     effective address                                                   register    displacement    immediate
+  3 # . op          subop               mod             rm32          base        index         scale       r32
+  4 # . 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
+  5 
+  6 # read all bytes from 'f' and store them into 's'
+  7 # abort if 's' is too small
+  8 slurp:  # f : (address buffered-file), s : (address stream byte) -> <void>
+  9     # pseudocode:
+ 10     #   while true
+ 11     #     if (s->write >= s->length) abort
+ 12     #     if (f->read >= f->write) populate stream from file
+ 13     #     if (f->write == 0) break
+ 14     #     AL = f->data[f->read]
+ 15     #     s->data[s->write] = AL
+ 16     #     ++f->read
+ 17     #     ++s->write
+ 18     # . prolog
+ 19     55/push-EBP
+ 20     89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
+ 21     # . save registers
+ 22     50/push-EAX
+ 23     51/push-ECX
+ 24     52/push-EDX
+ 25     56/push-ESI
+ 26     57/push-EDI
+ 27     # ESI = f
+ 28     8b/copy                         1/mod/*+disp8   5/rm32/EBP    .           .             .           6/r32/ESI   8/disp8         .                 # copy *(EBP+8) to ESI
+ 29     # ECX = f->read
+ 30     8b/copy                         1/mod/*+disp8   6/rm32/ESI    .           .             .           1/r32/ECX   8/disp8         .                 # copy *(ESI+8) to ECX
+ 31     # EDI = s
+ 32     8b/copy                         1/mod/*+disp8   5/rm32/EBP    .           .             .           7/r32/EDI   0xc/disp8       .                 # copy *(EBP+12) to EDI
+ 33     # EDX = s->write
+ 34     8b/copy                         0/mod/indirect  7/rm32/EDI    .           .             .           2/r32/EDX   .               .                 # copy *EDI to EDX
+ 35 $slurp:loop:
+ 36     # if (s->write >= s->length) abort
+ 37     3b/compare                      1/mod/*+disp8   7/rm32/EDI    .           .             .           2/r32/EDX   8/disp8         .                 # compare EDX with *(EDI+8)
+ 38     7d/jump-if-greater-or-equal  $slurp:abort/disp8
+ 39     # if (f->read >= f->write) populate stream from file
+ 40     3b/compare                      1/mod/*+disp8   6/rm32/ESI    .           .             .           1/r32/ECX   4/disp8         .                 # compare ECX with *(ESI+4)
+ 41     7c/jump-if-lesser  $slurp:from-stream/disp8
+ 42     # . clear-stream(stream = f+4)
+ 43     # . . push args
+ 44     8d/copy-address                 1/mod/*+disp8   6/rm32/ESI    .           .             .           0/r32/EAX   4/disp8         .                 # copy ESI+4 to EAX
+ 45     50/push-EAX
+ 46     # . . call
+ 47     e8/call  clear-stream/disp32
+ 48     # . . discard args
+ 49     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+ 50     # . f->read must now be 0; update its cache at ECX
+ 51     31/xor                          3/mod/direct    1/rm32/ECX    .           .             .           1/r32/ECX   .               .                 # clear ECX
+ 52     # . EAX = read(f->fd, stream = f+4)
+ 53     # . . push args
+ 54     50/push-EAX
+ 55     ff          6/subop/push        0/mod/indirect  6/rm32/ESI    .           .             .           .           .               .                 # push *ESI
+ 56     # . . call
+ 57     e8/call  read/disp32
+ 58     # . . discard args
+ 59     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+ 60     # if (f->write == 0) break
+ 61     # since f->read was initially 0, EAX is the same as f->write
+ 62     # . if (EAX == 0) return true
+ 63     3d/compare-EAX-and  0/imm32
+ 64     74/jump-if-equal  $slurp:end/disp8
+ 65 $slurp:from-stream:
+ 66     # AL = f->data[f->read]
+ 67     31/xor                          3/mod/direct    0/rm32/EAX    .           .             .           0/r32/EAX   .               .                 # clear EAX
+ 68     8a/copy-byte                    1/mod/*+disp8   4/rm32/sib    6/base/ESI  1/index/ECX   .           0/r32/AL    0x10/disp8      .                 # copy byte at *(ESI+ECX+16) to AL
+ 69     # s->data[s->write] = AL
+ 70     88/copy-byte                    1/mod/*+disp8   4/rm32/sib    7/base/EDI  2/index/EDX   .           0/r32/AL    0xc/disp8       .                 # copy AL to *(EDI+EDX+12)
+ 71     # ++f->read
+ 72     41/increment-ECX
+ 73     # ++s->write
+ 74     42/increment-EDX
+ 75     eb/jump  $slurp:loop/disp8
+ 76 $slurp:end:
+ 77     # save f->read
+ 78     89/copy                         1/mod/*+disp8   6/rm32/ESI    .           .             .           1/r32/ECX   8/disp8         .                 # copy ECX to *(ESI+8)
+ 79     # save s->write
+ 80     89/copy                         0/mod/indirect  7/rm32/EDI    .           .             .           2/r32/EDX   .               .                 # copy EDX to *EDI
+ 81     # . restore registers
+ 82     5f/pop-to-EDI
+ 83     5e/pop-to-ESI
+ 84     5a/pop-to-EDX
+ 85     59/pop-to-ECX
+ 86     58/pop-to-EAX
+ 87     # . epilog
+ 88     89/copy                         3/mod/direct    4/rm32/ESP    .           .             .           5/r32/EBP   .               .                 # copy EBP to ESP
+ 89     5d/pop-to-EBP
+ 90     c3/return
+ 91 
+ 92 $slurp:abort:
+ 93     # . _write(2/stderr, error)
+ 94     # . . push args
+ 95     68/push  "slurp: destination too small\n"/imm32
+ 96     68/push  2/imm32/stderr
+ 97     # . . call
+ 98     e8/call  _write/disp32
+ 99     # . . discard args
+100     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+101     # . syscall(exit, 1)
+102     bb/copy-to-EBX  1/imm32
+103     b8/copy-to-EAX  1/imm32/exit
+104     cd/syscall  0x80/imm8
+105     # never gets here
+106 
+107 test-slurp:
+108     # setup
+109     # . clear-stream(_test-stream)
+110     # . . push args
+111     68/push  _test-stream/imm32
+112     # . . call
+113     e8/call  clear-stream/disp32
+114     # . . discard args
+115     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+116     # . clear-stream(_test-buffered-file+4)
+117     # . . push args
+118     b8/copy-to-EAX  _test-buffered-file/imm32
+119     05/add-to-EAX  4/imm32
+120     50/push-EAX
+121     # . . call
+122     e8/call  clear-stream/disp32
+123     # . . discard args
+124     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+125     # . clear-stream(_test-tmp-stream)
+126     # . . push args
+127     68/push  _test-tmp-stream/imm32
+128     # . . call
+129     e8/call  clear-stream/disp32
+130     # . . discard args
+131     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+132     # write(_test-stream, "ab\ncd")
+133     # . . push args
+134     68/push  "ab\ncd"/imm32
+135     68/push  _test-stream/imm32
+136     # . . call
+137     e8/call  write/disp32
+138     # . . discard args
+139     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+140     # read a line from _test-stream (buffered by _test-buffered-file) into _test-tmp-stream
+141     # . EAX = slurp(_test-buffered-file, _test-tmp-stream)
+142     # . . push args
+143     68/push  _test-tmp-stream/imm32
+144     68/push  _test-buffered-file/imm32
+145     # . . call
+146     e8/call  slurp/disp32
+147     # . . discard args
+148     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+149     # check-stream-equal(_test-tmp-stream, "ab\ncd", msg)
+150     # . . push args
+151     68/push  "F - test-slurp"/imm32
+152     68/push  "ab\ncd"/imm32
+153     68/push  _test-tmp-stream/imm32
+154     # . . call
+155     e8/call  check-stream-equal/disp32
+156     # . . discard args
+157     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
+158     # end
+159     c3/return
+160 
+161 # . . vim:nowrap:textwidth=0
+
+ + + -- cgit 1.4.1-2-gfad0