Make func_800C213C match original ROM (#678)

* Make func_800C213C match original ROM

The C code for this function was very close to done, and was
functionally equivalent to the ROM.  This commit uses a few tricks
to convince the compiler to allocate the same registers as the original
ROM.  The two tricks used are:
1. Introduced a new temporary variable "yinc".
2. Added a "do while(0) {}" line in two places.

Both of these ideas came from the decomp-permuter tool.  I took the
do/while idea and guess as to what it might have been in the original
code.  I imagined that the "do while(0) {}" was probably left over from
a standard multi-line macro, which for some reason had an empty body.
I further suggest that maybe the empty body is because it was a feature
compiled out during RELEASE builds - perhaps a debug logging macro.

* Use simpler code for func_800C213C

Replaced dummy LOG macro with "do {} while(0);".  This version makes
less assumptions about what the original code looked like.

0 files changed, 0 insertions, 0 deletions