[llvm] [MachineLICM] Fix incorrect CSE on hoisted const load (PR #73007)

[Igor Kirillov via llvm-commits]

================
@@ -1422,6 +1422,11 @@ bool MachineLICMBase::EliminateCSE(
   if (MI->isImplicitDef())
     return false;
 
+  // Do not CSE normal loads because between them could be store instructions
+  // that change the loaded value
+  if (MI->mayLoad() && !MI->isDereferenceableInvariantLoad())
----------------
igogo-x86 wrote:

That's a particular case where we load constant from memory like this:
```
fadd float %tmp3.i, 1.000000e+10
```

Also, if at least one store is in the loop, we don't hoist loads.

https://github.com/llvm/llvm-project/pull/73007