Steam: Fails to launch (2507 regression, possibly incorrect optimization)
**What Game**
Steam (the store itself)

**Describe the bug**
Fails to launch on asahi post de4becc26e0c22a71b6615b3a2f35050e82fded0

**To Reproduce**
Launch steam

**Expected behavior**
The app launches

**System information:**
 - OS: Linux 6.14
 - CPU/SoC: Apple M1 Pro
 - Video driver version: Mesa 25.1.0-r100
 - RootFS used: Gentoo Asahi Rootfs
 - FEX version: FEX-2507, bisected to de4becc26e0c22a71b6615b3a2f35050e82fded0
 - Thunks Enabled: No

**Additional context**
 - Is this an x86 or x86-64 game: Both
 - Does this reproduce on AArch64 with Radeon/Intel/Nvidia: Untested
 - Is this a Vulkan game: N/A

Add any other context about the problem here.

Optimization performed by commit de4becc26e0c22a71b6615b3a2f35050e82fded0 appears to be incorrect:
It transforms 
```
"mov w20, w6",
"udiv x22, x0, x20",
"udiv x22, x0, x20",
```
into
```
"udiv x20, x0, x6",
"mov w4, w20",
```
Which is equivalent to transforming `(a // (b % 2**32)) % 2**32 into (a // b) % 2**32`, which is false for example with `a=2 b=1+2**32`.

Reverting the relevant commit fixes the issue.