[llvm] [Mips] Fix atomic min/max generate mips4 instructions when compiling for mips2 (PR #159717)

[via llvm-commits]

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@@ -432,23 +432,44 @@ bool MipsExpandPseudo::expandAtomicBinOpSubword(
   Register OldVal = I->getOperand(6).getReg();
   Register BinOpRes = I->getOperand(7).getReg();
   Register StoreVal = I->getOperand(8).getReg();
+  bool NoMovnInstr = (IsMin || IsMax) && !STI->hasMips4() && !STI->hasMips32();
 
   const BasicBlock *LLVM_BB = BB.getBasicBlock();
   MachineBasicBlock *loopMBB = MF->CreateMachineBasicBlock(LLVM_BB);
+  MachineBasicBlock *loop1MBB = NULL;
+  MachineBasicBlock *loop2MBB = NULL;
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yingopq wrote:

Applied.

https://github.com/llvm/llvm-project/pull/159717