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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
# Read a single byte from a stream.
4755 - read-byte (sometimes called getchar)
2018-11-20 07:11:00 +00:00
#
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
# We need to do this in machine code because streams need to be opaque types,
# and we don't yet support opaque types in Mu.
4755 - read-byte (sometimes called getchar)
2018-11-20 07:11:00 +00:00
== code
4802 Some automated commenting cleanup. Still needs more careful manual scanning. sed -i 's/^# 1-3/# . 1-3/' *.subx */*.subx sed -i 's/^# op/# . op/' *.subx */*.subx sed -i 's/# vim/# . . vim/' *.subx */*.subx sed -i 's/^ # push args/ # . . push args/' *.subx */*.subx sed -i 's/^ # discard args/ # . . discard args/' *.subx */*.subx sed -i 's/^ # call/ # . . call/' *.subx */*.subx sed -i 's/^ # prolog/ # . prolog/' *.subx */*.subx sed -i 's/^ # epilog/ # . epilog/' *.subx */*.subx sed -i 's/^ # save registers/ # . save registers/' *.subx */*.subx sed -i 's/^ # restore registers/ # . restore registers/' *.subx */*.subx sed -i 's/ operand / register /' *.subx */*.subx
2018-11-30 19:10:44 +00:00
# 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
4755 - read-byte (sometimes called getchar)
2018-11-20 07:11:00 +00:00
6733 - read utf-8 'grapheme' from byte stream No support for combining characters. Graphemes are currently just utf-8 encodings of a single Unicode code-point. No support for code-points that require more than 32 bits in utf-8.
2020-08-29 06:24:04 +00:00
# Return next byte value in eax, with top 3 bytes cleared.
6751 More copypasta. I'd be able to remove this duplication if we had first-class functions, but they involve an accessibility cost.
2020-09-08 05:09:43 +00:00
# Abort on reaching end of stream.
6733 - read utf-8 'grapheme' from byte stream No support for combining characters. Graphemes are currently just utf-8 encodings of a single Unicode code-point. No support for code-points that require more than 32 bits in utf-8.
2020-08-29 06:24:04 +00:00
read-byte: # s: (addr stream byte) -> result/eax: byte
# . prologue
55/push-ebp
89/copy 3/mod/direct 5/rm32/ebp . . . 4/r32/esp . . # copy esp to ebp
# . save registers
51/push-ecx
56/push-esi
# esi = s
8b/copy 1/mod/*+disp8 5/rm32/ebp . . . 6/r32/esi 8/disp8 . # copy *(ebp+8) to esi
# ecx = s->read
8b/copy 1/mod/*+disp8 6/rm32/esi . . . 1/r32/ecx 4/disp8 . # copy *(esi+4) to ecx
# if (f->read >= f->write) abort
3b/compare 0/mod/indirect 6/rm32/esi . . . 1/r32/ecx . . # compare ecx with *esi
0f 8d/jump-if->= $read-byte:abort/disp32
# result = f->data[f->read]
31/xor 3/mod/direct 0/rm32/eax . . . 0/r32/eax . . # clear eax
8a/copy-byte 1/mod/*+disp8 4/rm32/sib 6/base/esi 1/index/ecx . 0/r32/AL 0xc/disp8 . # copy byte at *(esi+ecx+12) to AL
# ++f->read
ff 0/subop/increment 1/mod/*+disp8 6/rm32/esi . . . . 4/disp8 . # increment *(esi+4)
$read-byte:end:
# . restore registers
5e/pop-to-esi
59/pop-to-ecx
# . epilogue
89/copy 3/mod/direct 4/rm32/esp . . . 5/r32/ebp . . # copy ebp to esp
5d/pop-to-ebp
c3/return
$read-byte:abort:
print call stack on all low-level errors
2021-05-15 07:15:24 +00:00
(abort "read-byte: empty stream")
6733 - read utf-8 'grapheme' from byte stream No support for combining characters. Graphemes are currently just utf-8 encodings of a single Unicode code-point. No support for code-points that require more than 32 bits in utf-8.
2020-08-29 06:24:04 +00:00
# never gets here
.
2021-08-10 12:52:48 +00:00
# Return next byte value in eax, with top 3 bytes cleared.
# Abort on reaching end of stream.
peek-byte: # s: (addr stream byte) -> result/eax: byte
# . prologue
55/push-ebp
89/copy 3/mod/direct 5/rm32/ebp . . . 4/r32/esp . . # copy esp to ebp
# . save registers
51/push-ecx
56/push-esi
# esi = s
8b/copy 1/mod/*+disp8 5/rm32/ebp . . . 6/r32/esi 8/disp8 . # copy *(ebp+8) to esi
# ecx = s->read
8b/copy 1/mod/*+disp8 6/rm32/esi . . . 1/r32/ecx 4/disp8 . # copy *(esi+4) to ecx
# if (f->read >= f->write) abort
3b/compare 0/mod/indirect 6/rm32/esi . . . 1/r32/ecx . . # compare ecx with *esi
0f 8d/jump-if->= $peek-byte:abort/disp32
# result = f->data[f->read]
31/xor 3/mod/direct 0/rm32/eax . . . 0/r32/eax . . # clear eax
8a/copy-byte 1/mod/*+disp8 4/rm32/sib 6/base/esi 1/index/ecx . 0/r32/AL 0xc/disp8 . # copy byte at *(esi+ecx+12) to AL
$peek-byte:end:
# . restore registers
5e/pop-to-esi
59/pop-to-ecx
# . epilogue
89/copy 3/mod/direct 4/rm32/esp . . . 5/r32/ebp . . # copy ebp to esp
5d/pop-to-ebp
c3/return
$peek-byte:abort:
(abort "peek-byte: empty stream")
# never gets here
4755 - read-byte (sometimes called getchar)
2018-11-20 07:11:00 +00:00
== data
5883 - drop the `ref` keyword When I created it I was conflating two things: a) needing to refer to just the start, rather than the whole, and b) counting indirections. Both are kinda ill-posed. Now Mu will have just `addr` and `handle` types. Normal types will translate implicitly to `addr` types, while `handle` will always require explicit handling.
2020-01-12 20:11:15 +00:00
_test-input-stream: # (stream byte)
standardize test input/output/error streams
2019-08-13 19:27:15 +00:00
# current write index
0/imm32
reading from streams The Mu shell has no string literals, only streams. No random access, only sequential access. But I've been playing fast and loose with its read pointer until now. Hopefully things are cleaned up now.
2021-07-04 01:27:01 +00:00
$_test-input-stream->read:
standardize test input/output/error streams
2019-08-13 19:27:15 +00:00
# current read index
0/imm32
6182 - start of support for safe handles So far it's unclear how to do this in a series of small commits. Still nibbling around the edges. In this commit we standardize some terminology: The length of an array or stream is denominated in the high-level elements. The _size_ is denominated in bytes. The thing we encode into the type is always the size, not the length. There's still an open question of what to do about the Mu `length` operator. I'd like to modify it to provide the length. Currently it provides the size. If I can't fix that I'll rename it.
2020-04-03 19:35:53 +00:00
# size
6908 - compiling all floating-point operations We don't yet support emulating these instructions in `bootstrap`. But generated binaries containing them run natively just fine.
2020-10-01 04:17:37 +00:00
0x400/imm32 # 1024 bytes
# data (64 lines x 16 bytes/line)
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
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00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
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00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
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00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
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00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
standardize test input/output/error streams
2019-08-13 19:27:15 +00:00
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
4802 Some automated commenting cleanup. Still needs more careful manual scanning. sed -i 's/^# 1-3/# . 1-3/' *.subx */*.subx sed -i 's/^# op/# . op/' *.subx */*.subx sed -i 's/# vim/# . . vim/' *.subx */*.subx sed -i 's/^ # push args/ # . . push args/' *.subx */*.subx sed -i 's/^ # discard args/ # . . discard args/' *.subx */*.subx sed -i 's/^ # call/ # . . call/' *.subx */*.subx sed -i 's/^ # prolog/ # . prolog/' *.subx */*.subx sed -i 's/^ # epilog/ # . epilog/' *.subx */*.subx sed -i 's/^ # save registers/ # . save registers/' *.subx */*.subx sed -i 's/^ # restore registers/ # . restore registers/' *.subx */*.subx sed -i 's/ operand / register /' *.subx */*.subx
2018-11-30 19:10:44 +00:00
# . . vim:nowrap:textwidth=0