29 lines
1.2 KiB
Markdown
29 lines
1.2 KiB
Markdown
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This is just a naive domestic PowerPC simulator, but I think you'll be amused
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by its presumption.
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The simulator implements just enough of the instruction set to make the tests
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pass. Certain features aren't supported at all (and an effort has been made
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to detect this and error out). The FPU is crudely approximated using the
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native floating-point support, doesn't support reading and writing FPSCR, and
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will almost certainly produce incorrect results. Plus, there are bugs. It's
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also likely to be very, very slow.
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However, it should be easily extensible and the emulator core is only about
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500 lines of code.
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Instructions are defined in `instructions.dat`; `mkdispatcher.lua` reads
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these in and generates the instruction decoder. `emu.c` contains the main
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emulator core. `main.c` contains the application front end and the incredibly
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crude syscall interface.
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TODO:
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- overflow bit support (instructions that try to set OV error out)
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- mtcrf
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- read string / write string
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- factor out the ELF loader, and linux68k/emu uses it too
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- floating point condition bits
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- bit-for-bit FPU emulation, although this looks like a huge amount of work
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It was written from scratch for the ACK by me, David Given.
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