7842 - new directory organization

Baremetal is now the default build target and therefore has its sources
at the top-level. Baremetal programs build using the phase-2 Mu toolchain
that requires a Linux kernel. This phase-2 codebase which used to be at
the top-level is now under the linux/ directory. Finally, the phase-2 toolchain,
while self-hosting, has a way to bootstrap from a C implementation, which
is now stored in linux/bootstrap. The bootstrap C implementation uses some
literate programming tools that are now in linux/bootstrap/tools.

So the whole thing has gotten inverted. Each directory should build one
artifact and include the main sources (along with standard library). Tools
used for building it are relegated to sub-directories, even though those
tools are often useful in their own right, and have had lots of interesting
programs written using them.

A couple of things have gotten dropped in this process:
  - I had old ways to run on just a Linux kernel, or with a Soso kernel.
    No more.
  - I had some old tooling for running a single test at the cursor. I haven't
    used that lately. Maybe I'll bring it back one day.

The reorg isn't done yet. Still to do:
  - redo documentation everywhere. All the README files, all other markdown,
    particularly vocabulary.md.
  - clean up how-to-run comments at the start of programs everywhere
  - rethink what to do with the html/ directory. Do we even want to keep
    supporting it?

In spite of these shortcomings, all the scripts at the top-level, linux/
and linux/bootstrap are working. The names of the scripts also feel reasonable.
This is a good milestone to take stock at.

1 files changed, 241 insertions, 0 deletions

diff --git a/linux/129emit-hex.subx b/linux/129emit-hex.subx
new file mode 100644
index 00000000..d8869956
--- /dev/null
+++ b/linux/129emit-hex.subx
@@ -0,0 +1,241 @@
+== code
+#   instruction                     effective address                                                   register    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
+
+# print 'n' in hex in 'width' bytes in lower-endian order, with a space after every byte
+emit-hex:  # out: (addr buffered-file), n: int, width: int
+    # . prologue
+    55/push-ebp
+    89/copy                         3/mod/direct    5/rm32/ebp    .           .             .           4/r32/esp   .               .                 # copy esp to ebp
+    # . save registers
+    50/push-eax
+    51/push-ecx
+    52/push-edx
+    53/push-ebx
+    57/push-edi
+    # edi = out
+    8b/copy                         1/mod/*+disp8   5/rm32/ebp    .           .             .           7/r32/edi   8/disp8         .                 # copy *(ebp+8) to edi
+    # ebx = n
+    8b/copy                         1/mod/*+disp8   5/rm32/ebp    .           .             .           3/r32/ebx   0xc/disp8       .                 # copy *(ebp+12) to ebx
+    # edx = width
+    8b/copy                         1/mod/*+disp8   5/rm32/ebp    .           .             .           2/r32/edx   0x10/disp8      .                 # copy *(ebp+16) to edx
+    # var curr/ecx: int = 0
+    31/xor                          3/mod/direct    1/rm32/ecx    .           .             .           1/r32/ecx   .               .                 # clear ecx
+$emit-hex:loop:
+    # if (curr >= width) break
+    39/compare                      3/mod/direct    1/rm32/ecx    .           .             .           2/r32/edx   .               .                 # compare ecx with edx
+    7d/jump-if->=  $emit-hex:end/disp8
+    # write-byte-hex-buffered(out, ebx)  # only BL used
+    # . . push args
+    53/push-ebx
+    57/push-edi
+    # . . call
+    e8/call  write-byte-hex-buffered/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               8/imm32           # add to esp
+    # write-byte-buffered(out, ' ')
+    # . . push args
+    68/push  0x20/imm32/space
+    57/push-edi
+    # . . call
+    e8/call  write-byte-buffered/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               8/imm32           # add to esp
+    # ebx = ebx >> 8
+    c1/shift    5/subop/logic-right 3/mod/direct    3/rm32/ebx    .           .             .           .           .               8/imm8            # shift ebx right by 8 bits, while padding zeroes
+$emit-hex:continue:
+    # ++curr
+    41/increment-ecx
+    eb/jump  $emit-hex:loop/disp8
+$emit-hex:end:
+    # . restore registers
+    5f/pop-to-edi
+    5b/pop-to-ebx
+    5a/pop-to-edx
+    59/pop-to-ecx
+    58/pop-to-eax
+    # . epilogue
+    89/copy                         3/mod/direct    4/rm32/esp    .           .             .           5/r32/ebp   .               .                 # copy ebp to esp
+    5d/pop-to-ebp
+    c3/return
+
+test-emit-hex-single-byte:
+    # setup
+    # . clear-stream(_test-output-stream)
+    # . . push args
+    68/push  _test-output-stream/imm32
+    # . . call
+    e8/call  clear-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               4/imm32           # add to esp
+    # . clear-stream($_test-output-buffered-file->buffer)
+    # . . push args
+    68/push  $_test-output-buffered-file->buffer/imm32
+    # . . call
+    e8/call  clear-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               4/imm32           # add to esp
+    # emit-hex(_test-output-buffered-file, 0xab, 1)
+    # . . push args
+    68/push  1/imm32
+    68/push  0xab/imm32
+    68/push  _test-output-buffered-file/imm32
+    # . . call
+    e8/call  emit-hex/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               0xc/imm32         # add to esp
+    # flush(_test-output-buffered-file)
+    # . . push args
+    68/push  _test-output-buffered-file/imm32
+    # . . call
+    e8/call  flush/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               4/imm32           # add to esp
+    # check-ints-equal(*_test-output-stream->data, 'ab ', msg)
+    # . . push args
+    68/push  "F - test-emit-hex-single-byte"/imm32
+    68/push  0x206261/imm32
+    # . . push *_test-output-stream->data
+    b8/copy-to-eax  _test-output-stream/imm32
+    ff          6/subop/push        1/mod/*+disp8   0/rm32/eax    .           .             .           .           0xc/disp8       .                 # push *(eax+12)
+    # . . call
+    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
+
+test-emit-hex-multiple-byte:
+    # setup
+    # . clear-stream(_test-output-stream)
+    # . . push args
+    68/push  _test-output-stream/imm32
+    # . . call
+    e8/call  clear-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               4/imm32           # add to esp
+    # . clear-stream($_test-output-buffered-file->buffer)
+    # . . push args
+    68/push  $_test-output-buffered-file->buffer/imm32
+    # . . call
+    e8/call  clear-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               4/imm32           # add to esp
+    # emit-hex(_test-output-buffered-file, 0x1234, 2)
+    # . . push args
+    68/push  2/imm32
+    68/push  0x1234/imm32
+    68/push  _test-output-buffered-file/imm32
+    # . . call
+    e8/call  emit-hex/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               0xc/imm32         # add to esp
+    # flush(_test-output-buffered-file)
+    # . . push args
+    68/push  _test-output-buffered-file/imm32
+    # . . call
+    e8/call  flush/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               4/imm32           # add to esp
+    # check-stream-equal(_test-output-stream, "34 12 ", msg)
+    # . . push args
+    68/push  "F - test-emit-hex-multiple-byte/1"/imm32
+    68/push  "34 12 "/imm32
+    68/push  _test-output-stream/imm32
+    # . . call
+    e8/call  check-stream-equal/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               0xc/imm32         # add to esp
+    # . end
+    c3/return
+
+test-emit-hex-zero-pad:
+    # setup
+    # . clear-stream(_test-output-stream)
+    # . . push args
+    68/push  _test-output-stream/imm32
+    # . . call
+    e8/call  clear-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               4/imm32           # add to esp
+    # . clear-stream($_test-output-buffered-file->buffer)
+    # . . push args
+    68/push  $_test-output-buffered-file->buffer/imm32
+    # . . call
+    e8/call  clear-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               4/imm32           # add to esp
+    # emit-hex(_test-output-buffered-file, 0xab, 2)
+    # . . push args
+    68/push  2/imm32
+    68/push  0xab/imm32
+    68/push  _test-output-buffered-file/imm32
+    # . . call
+    e8/call  emit-hex/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               0xc/imm32         # add to esp
+    # flush(_test-output-buffered-file)
+    # . . push args
+    68/push  _test-output-buffered-file/imm32
+    # . . call
+    e8/call  flush/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               4/imm32           # add to esp
+    # check(_test-output-stream->data == 'ab 00 ')
+    # . . push args
+    68/push  "F - test-emit-hex-zero-pad/1"/imm32
+    68/push  "ab 00 "/imm32
+    68/push  _test-output-stream/imm32
+    # . . call
+    e8/call  check-stream-equal/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               0xc/imm32         # add to esp
+    # . end
+    c3/return
+
+test-emit-hex-negative:
+    # setup
+    # . clear-stream(_test-output-stream)
+    # . . push args
+    68/push  _test-output-stream/imm32
+    # . . call
+    e8/call  clear-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               4/imm32           # add to esp
+    # . clear-stream($_test-output-buffered-file->buffer)
+    # . . push args
+    68/push  $_test-output-buffered-file->buffer/imm32
+    # . . call
+    e8/call  clear-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               4/imm32           # add to esp
+    # emit-hex(_test-output-buffered-file, -1, 2)
+    # . . push args
+    68/push  2/imm32
+    68/push  -1/imm32
+    68/push  _test-output-buffered-file/imm32
+    # . . call
+    e8/call  emit-hex/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               0xc/imm32         # add to esp
+    # flush(_test-output-buffered-file)
+    # . . push args
+    68/push  _test-output-buffered-file/imm32
+    # . . call
+    e8/call  flush/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               4/imm32           # add to esp
+    # check-stream-equal(_test-output-stream == "ff ff ")
+    # . . push args
+    68/push  "F - test-emit-hex-negative/1"/imm32
+    68/push  "ff ff "/imm32
+    68/push  _test-output-stream/imm32
+    # . . call
+    e8/call  check-stream-equal/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               0xc/imm32         # add to esp
+    # . end
+    c3/return
+
+# . . vim:nowrap:textwidth=0