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ReC98/libs/master.lib/master.inc

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[Reverse-engineering] [th02/th04/th05] Score update and display The TH02 version is a piece of cake… … but TH04 starts turning it into this un-decompilable piece of unnecessarily micro-optimized ZUN code. Couldn't have chosen anything better for the first separate ASM translation unit. Aside from now having to convert names of exported *variables* to uppercase for visibility in ASM translation units, the most notable lesson in this was the one about avoiding fixup overflows. From the Borland C++ Version 4.0 User's Guide: "In an assembly language program, a fixup overflow frequently occurs if you have declared an external variable within a segment definition, but this variable actually exists in a different segment." Can't be restated often enough. Completes P0032, funded by zorg.
2019-09-18 16:33:38 +00:00
; ReC98
; Relevant function definitions from master.h, together with the necessary
; types. Meant as a master.h equivalent for standalone, non-slice ASM
; translation units.
include libs/master.lib/macros.inc
[Separate translation units] .PI: Row loop for masked blitting (undecompilable) Reason: Pascal calling convention with function parameters but no stack frame. Theoretically we can __emit__() everything inside this function, but there's no way we can get a `RETN 8` this way. Oh, and it also accesses SI and DI without backing them up to the stack. And thanks to TLINK apparently not reporting fixup overflows when segments are small enough (?), it took quite a while to get that CALL correct and not weirdly offset by 32 bytes. 😕 Part of P0134, funded by [Anonymous].
2021-02-18 18:40:37 +00:00
EGC_OFF procdesc pascal far
[Reverse-engineering] [th02/th04/th05] Score update and display The TH02 version is a piece of cake… … but TH04 starts turning it into this un-decompilable piece of unnecessarily micro-optimized ZUN code. Couldn't have chosen anything better for the first separate ASM translation unit. Aside from now having to convert names of exported *variables* to uppercase for visibility in ASM translation units, the most notable lesson in this was the one about avoiding fixup overflows. From the Borland C++ Version 4.0 User's Guide: "In an assembly language program, a fixup overflow frequently occurs if you have declared an external variable within a segment definition, but this variable actually exists in a different segment." Can't be restated often enough. Completes P0032, funded by zorg.
2019-09-18 16:33:38 +00:00
GAIJI_PUTSA procdesc pascal far \
x:word, y:word, strp_seg:word, strp_off:word, atrb:word
[Decompilation] [th05] pi_put_8(), pi_put_quarter_8() > assigning to the DI register immediately before a CALL Yeah, no amount of comma operator trickery can get *that* out of this compiler. Also, these TH05 .PI functions are the only place in PC-98 Touhou with a `IMUL DI, imm8` instruction, which is impossible to get out of Turbo C++'s built-in assembler. Well, at least the `if` branches decompile somewhat nicely. Part of P0134, funded by [Anonymous].
2021-02-14 11:51:12 +00:00
GRAPH_PACK_PUT_8_NOCLIP procdesc pascal far \
left:word, top:word, linepat_sgm:word, linepat_off:word, len:word
[Separate translation units] [th05] pi_free() (undecompilable) Well, it *would* have been decompilable, but that ridiculous placement of the nullptr assignment would have forced the entire function call to be spelled out in inline ASM, verbatim. No amount of comma operator trickery would have generated the same instructions either. And for a function this small and obvious in what its decompilation *should* be, it really defeated the purpose of adding a separate translation unit… Part of P0134, funded by [Anonymous].
2021-02-12 16:39:51 +00:00
GRAPH_PI_FREE procdesc pascal far \
header:far ptr, image:far ptr
[Separate translation units] [th03] .CDG display (undecompilable) Reason: Self-modifying. -.- Part of P0137, funded by [Anonymous].
2021-03-28 13:03:42 +00:00
extrn GRCG_SETCOLOR:proc
[Separate translation units] [th05] pi_free() (undecompilable) Well, it *would* have been decompilable, but that ridiculous placement of the nullptr assignment would have forced the entire function call to be spelled out in inline ASM, verbatim. No amount of comma operator trickery would have generated the same instructions either. And for a function this small and obvious in what its decompilation *should* be, it really defeated the purpose of adding a separate translation unit… Part of P0134, funded by [Anonymous].
2021-02-12 16:39:51 +00:00
PALETTE_SHOW procdesc pascal far