[llvm] [MachineLICM] Rematerialize instructions that may be hoisted before LICM (PR #158479)

[Matt Arsenault via llvm-commits]

================
@@ -167,3 +167,48 @@ bool llvm::isCycleInvariant(const MachineCycle *Cycle, MachineInstr &I) {
   // If we got this far, the instruction is cycle invariant!
   return true;
 }
+
+bool llvm::mayLoadFromGOTOrConstantPool(MachineInstr &MI) {
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arsenm wrote:

```suggestion
bool llvm::mayLoadFromGOTOrConstantPool(MachineInstr &MI) {
```
const. Also could just be directly a function of MachineInstr? 

https://github.com/llvm/llvm-project/pull/158479