[llvm] [IR] Improve code in isIdenticalToWhenDefined (NFC) (PR #151881)

[Longsheng Mou via llvm-commits]

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@@ -942,14 +942,13 @@ bool Instruction::isIdenticalToWhenDefined(const Instruction *I,
 
   // We have two instructions of identical opcode and #operands.  Check to see
   // if all operands are the same.
-  if (!std::equal(op_begin(), op_end(), I->op_begin()))
+  if (!equal(operands(), I->operands()))
     return false;
 
   // WARNING: this logic must be kept in sync with EliminateDuplicatePHINodes()!
-  if (const PHINode *thisPHI = dyn_cast<PHINode>(this)) {
-    const PHINode *otherPHI = cast<PHINode>(I);
-    return std::equal(thisPHI->block_begin(), thisPHI->block_end(),
-                      otherPHI->block_begin());
+  if (const PHINode *Phi = dyn_cast<PHINode>(this)) {
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CoTinker wrote:

nit: Why chang the variable name from `thisPHI` to `Phi`?

https://github.com/llvm/llvm-project/pull/151881