[llvm] [SimplifyCFG] Use hash map to continue hoisting the common instructions (PR #78615)

[via llvm-commits]

================
@@ -1582,19 +1582,29 @@ hoistLockstepIdenticalDPValues(Instruction *TI, Instruction *I1,
   }
 }
 
+// Hash instructions based on following factors:
+// 1- Instruction Opcode
+// 2- Instruction type
+// 3- Instruction operands
+llvm::hash_code getHash(Instruction *Instr) {
+  std::vector<Value *> operands(Instr->op_begin(), Instr->op_end());
+  return llvm::hash_combine(
+      Instr->getOpcode(), Instr->getType(),
+      hash_combine_range(operands.begin(), operands.end()));
----------------
RouzbehPaktinat wrote:

That's right but I never iterate the hashmap, I just look it up using a key. It won't have that non-deterministic behavior.

https://github.com/llvm/llvm-project/pull/78615