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README.md

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+This was an attempt at programmatically transplanting code between the 68k
+MainCode parts of different Macintosh ROMs. The idea was to help clarify the
+important features of the NewWorld images that refuse to boot my Mac mini.
+
+It works only for GoNative (the ROM Code Fragment Manager), although there is
+some reusable supporting code. This is likely a dead end, but I thought I'd
+share some insights that I have gained into the ROM-patching problem.
+
+Matching the commonly called and rarely changed ROM glue code (GetHandleSize
+etc) is easy, but other functions are very hard. I considered using a known-good
+ROM disassembly and generating regular expressions that would match only the
+major opcodes of a given function.
+
+Closely coupled functions can have subtle but catastrophic incompatibility at
+the binary level, e.g. in struct layouts.
+
+You need to decide whether to patch a function's callers or place a BRA.L in the
+function itself. Then, you need to decide where and how control will return to
+the original ROM.