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3464bb705a
This has been one of the most weird functions I ever decompiled. I will
share a few tricks I learnt. In short, I tried inlining as much as
possible by removing all the temps.
---
```c
switch (self->step) {
...
case 2:
isEntityAlive = 0;
if (self->step != 2) {
return;
}
```
This was the output from M2C. As there is no way that `self->step` is
different than `2`, deleting had no effect on the matching.
---
```c
var_v0 = self->step;
switch (var_v0) {
case 1:
...
if (statement) {
self->step++;
}
...
D_SOME_VARIABLE = var_v0;
}
```
This was another very weird one. I couldn't understand why
`D_SOME_VARIABLE` was assigned that way much further down the `case 1`.
The way I fixed it is that `var_v0` was always `1` due to `case 1:`. By
doing `D_SOME_VARIABLE = 1` I got a match.
---
```c
temp_a0_2 = D_80174C2C + 1;
...
D_80174C2C = temp_a0_2 & -(temp_a0_2 < 0x10);
```
To understand this madness I used a random C compiler I found online and
tested in a `for` loop what's the output for all the given `temp_a0_2`.
It seemed the value never changed but over `16` the value was always 0.
I logically re-written that statement into something that made logically
more sense for me and it matched, even if it looks very different from
the original:
```c
D_80174C2C++;
D_80174C2C = D_80174C2C >= 16 ? 0 : D_80174C2C;
```
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| .. | ||
| asm-differ@6d3e4c44d1 | ||
| dups | ||
| function_finder | ||
| gfxsotn | ||
| lints/sotn-lint | ||
| m2c@0813874880 | ||
| maspsx@ae43f009e3 | ||
| n64splat@8acd2fad74 | ||
| saturn-splitter@8d549a8042 | ||
| sotn-debugmodule | ||
| sotn-disk | ||
| splat_ext | ||
| split_jpt_yaml | ||
| vab-ex | ||
| analyze_calls.py | ||
| bin2c.py | ||
| decompile.py | ||
| gfxstage.py | ||
| m2ctx.py | ||
| permuter_settings.toml | ||
| png2bin.py | ||
| progress.py | ||
| requirements-debian.txt | ||
| requirements-python.txt | ||
| richter_symbols.py | ||
| sotn-str.py | ||
| spritesheet.py | ||
| symbols_test.py | ||
| symbols.py | ||
| tools.mk | ||
| update.h | ||