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.
2021-03-04 06:09:50 +00:00
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# write: like _write, but also support in-memory streams in addition to file
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# descriptors.
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2021-01-16 04:51:02 +00:00
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#
|
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.
2021-03-04 06:09:50 +00:00
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# Our first dependency-injected and testable primitive. We can pass it either
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# a file descriptor or an address to a stream. If a file descriptor is passed
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# in, we _write to it using the right syscall. If a 'fake file descriptor' or
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# stream is passed in, we append to the stream. This lets us redirect output
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# in tests and check it later.
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#
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# We assume our data segment will never begin at an address shorter than
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# 0x08000000, so any smaller arguments are assumed to be real file descriptors.
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#
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# A stream looks like this:
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# read: int # index at which to read next
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# write: int # index at which writes go
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# data: (array byte) # prefixed by size as usual
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2021-01-16 04:51:02 +00:00
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2021-01-14 05:41:45 +00:00
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== code
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2021-01-10 02:55:24 +00:00
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# instruction effective address register displacement immediate
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# . op subop mod rm32 base index scale r32
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# . 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
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|
|
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.
2021-03-04 06:09:50 +00:00
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# TODO: come up with a way to signal when a write to disk fails
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write: # f: fd or (addr stream byte), s: (addr array byte)
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2021-01-10 02:55:24 +00:00
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# . prologue
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55/push-ebp
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89/copy 3/mod/direct 5/rm32/ebp . . . 4/r32/esp . . # copy esp to ebp
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# if (s == 0) return
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81 7/subop/compare 1/mod/*+disp8 5/rm32/ebp . . . . 0xc/disp8 0/imm32 # compare *(ebp+12)
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74/jump-if-= $write:end/disp8
|
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.
2021-03-04 06:09:50 +00:00
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# if (f < 0x08000000) _write(f, s) and return # f can't be a user-mode address, so treat it as a kernel file descriptor
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81 7/subop/compare 1/mod/*+disp8 5/rm32/ebp . . . . 8/disp8 0x08000000/imm32 # compare *(ebp+8)
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73/jump-if-addr>= $write:fake/disp8
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# . . push args
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ff 6/subop/push 1/mod/*+disp8 5/rm32/ebp . . . . 0xc/disp8 . # push *(ebp+12)
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ff 6/subop/push 1/mod/*+disp8 5/rm32/ebp . . . . 8/disp8 . # push *(ebp+8)
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# . . call
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e8/call _write/disp32
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# . . discard args
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81 0/subop/add 3/mod/direct 4/rm32/esp . . . . . 8/imm32 # add to esp
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eb/jump $write:end/disp8
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$write:fake:
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# otherwise, treat 'f' as a stream to append to
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2021-01-10 02:55:24 +00:00
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# . save registers
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50/push-eax
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51/push-ecx
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52/push-edx
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53/push-ebx
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# ecx = f
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8b/copy 1/mod/*+disp8 5/rm32/ebp . . 1/r32/ecx 8/disp8 . # copy *(ebp+8) to ecx
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# edx = f->write
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8b/copy 0/mod/indirect 1/rm32/ecx . . . 2/r32/edx . . # copy *ecx to edx
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# ebx = f->size
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8b/copy 1/mod/*+disp8 1/rm32/ecx . . . 3/r32/ebx 8/disp8 . # copy *(ecx+8) to ebx
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# eax = _append-3(&f->data[f->write], &f->data[f->size], s)
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# . . push s
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ff 6/subop/push 1/mod/*+disp8 5/rm32/ebp . . . . 0xc/disp8 . # push *(ebp+12)
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# . . push &f->data[f->size]
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8d/copy-address 1/mod/*+disp8 4/rm32/sib 1/base/ecx 3/index/ebx . 3/r32/ebx 0xc/disp8 . # copy ecx+ebx+12 to ebx
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53/push-ebx
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# . . push &f->data[f->write]
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8d/copy-address 1/mod/*+disp8 4/rm32/sib 1/base/ecx 2/index/edx . 3/r32/ebx 0xc/disp8 . # copy ecx+edx+12 to ebx
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53/push-ebx
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# . . call
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e8/call _append-3/disp32
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# . . discard args
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81 0/subop/add 3/mod/direct 4/rm32/esp . . . . . 0xc/imm32 # add to esp
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# f->write += eax
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01/add 0/mod/indirect 1/rm32/ecx . . . 0/r32/eax . . # add eax to *ecx
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# . restore registers
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5b/pop-to-ebx
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5a/pop-to-edx
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59/pop-to-ecx
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58/pop-to-eax
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$write:end:
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# . epilogue
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89/copy 3/mod/direct 4/rm32/esp . . . 5/r32/ebp . . # copy ebp to esp
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5d/pop-to-ebp
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c3/return
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|
2021-01-16 04:51:02 +00:00
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test-write-single:
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# clear-stream(_test-stream)
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# . . push args
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68/push _test-stream/imm32
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# . . call
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e8/call clear-stream/disp32
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# . . discard args
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81 0/subop/add 3/mod/direct 4/rm32/esp . . . . . 4/imm32 # add to esp
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# write(_test-stream, "Ab")
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# . . push args
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68/push "Ab"/imm32
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68/push _test-stream/imm32
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# . . call
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e8/call write/disp32
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# . . discard args
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81 0/subop/add 3/mod/direct 4/rm32/esp . . . . . 8/imm32 # add to esp
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# check-ints-equal(*_test-stream->data, 41/A 62/b 00 00, msg)
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# . . push args
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68/push "F - test-write-single"/imm32
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68/push 0x006241/imm32/Ab
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# . . push *_test-stream->data
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b8/copy-to-eax _test-stream/imm32
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ff 6/subop/push 1/mod/*+disp8 0/rm32/eax . . . . 0xc/disp8 . # push *(eax+12)
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# . . call
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e8/call check-ints-equal/disp32
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# . . discard args
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81 0/subop/add 3/mod/direct 4/rm32/esp . . . . . 0xc/imm32 # add to esp
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# end
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c3/return
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test-write-appends:
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|
|
# clear-stream(_test-stream)
|
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# . . push args
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68/push _test-stream/imm32
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|
# . . call
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e8/call clear-stream/disp32
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# . . discard args
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81 0/subop/add 3/mod/direct 4/rm32/esp . . . . . 4/imm32 # add to esp
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# write(_test-stream, "C")
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# . . push args
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68/push "C"/imm32
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68/push _test-stream/imm32
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# . . call
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e8/call write/disp32
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# . . discard args
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81 0/subop/add 3/mod/direct 4/rm32/esp . . . . . 8/imm32 # add to esp
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# write(_test-stream, "D")
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|
# . . push args
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68/push "D"/imm32
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68/push _test-stream/imm32
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|
# . . call
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|
e8/call write/disp32
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|
# . . discard args
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|
81 0/subop/add 3/mod/direct 4/rm32/esp . . . . . 8/imm32 # add to esp
|
|
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|
|
# check-ints-equal(*_test-stream->data, 43/C 44/D 00 00, msg)
|
|
|
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|
# . . push args
|
|
|
|
|
68/push "F - test-write-appends"/imm32
|
|
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|
68/push 0x00004443/imm32/C-D
|
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|
# . . push *_test-stream->data
|
|
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|
b8/copy-to-eax _test-stream/imm32
|
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|
ff 6/subop/push 1/mod/*+disp8 0/rm32/eax . . . . 0xc/disp8 . # push *(eax+12)
|
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|
# . . call
|
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|
e8/call check-ints-equal/disp32
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|
# . . discard args
|
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|
81 0/subop/add 3/mod/direct 4/rm32/esp . . . . . 0xc/imm32 # add to esp
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# end
|
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c3/return
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== data
|
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_test-stream: # (stream byte)
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# current write index
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0/imm32
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# current read index
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0/imm32
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# size
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0x10/imm32
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# data (2 lines x 8 bytes/line)
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00 00 00 00 00 00 00 00
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00 00 00 00 00 00 00 00
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2021-01-10 02:55:24 +00:00
|
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|
# . . vim:nowrap:textwidth=0
|