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.
40 lines
739 B
Forth
40 lines
739 B
Forth
# Some slow but convenient helpers
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# slow, iterative shift-left instruction
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# preconditions: _nr >= 0, _dr > 0
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fn repeated-shift-left nr: int, dr: int -> _/eax: int {
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var result/eax: int <- copy nr
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{
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compare dr, 0
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break-if-<=
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result <- shift-left 1
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decrement dr
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loop
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}
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return result
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}
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# slow, iterative shift-right instruction
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# preconditions: _nr >= 0, _dr > 0
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fn repeated-shift-right nr: int, dr: int -> _/eax: int {
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var result/eax: int <- copy nr
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{
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compare dr, 0
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break-if-<=
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result <- shift-right 1
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decrement dr
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loop
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}
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return result
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}
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fn abs n: int -> _/eax: int {
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var result/eax: int <- copy n
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{
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compare n, 0
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break-if->=
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result <- negate
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}
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return result
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}
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