[NFC] Remove shouldCoalesce from aie base since we want to keep aie2 results stable

Author: niwinanto

llvm/lib/Target/AIE/AIEBaseRegisterInfo.cpp

@@ -19,38 +19,11 @@
 #include "llvm/CodeGen/LiveIntervals.h"
 
 using namespace llvm;
-extern cl::opt<bool> EnableCoalescingForWideCopy;
 
 bool AIEBaseRegisterInfo::shouldCoalesce(
     MachineInstr *MI, const TargetRegisterClass *SrcRC, unsigned SubReg,
     const TargetRegisterClass *DstRC, unsigned DstSubReg,
     const TargetRegisterClass *NewRC, LiveIntervals &LIS) const {
-  MachineBasicBlock *MBB = MI->getParent();
-  if (EnableCoalescingForWideCopy || AIELoopUtils::isSingleMBBLoop(MBB)) {
-    return TargetRegisterInfo::shouldCoalesce(MI, SrcRC, SubReg, DstRC,
-                                              DstSubReg, NewRC, LIS);
-  }
-  const unsigned SrcSize = getRegSizeInBits(*SrcRC);
-  const unsigned DstSize = getRegSizeInBits(*DstRC);
-  MachineFunction *MF = MI->getMF();
-  const AIEBaseInstrInfo *TII =
-      static_cast<const AIEBaseInstrInfo *>(MF->getSubtarget().getInstrInfo());
-  const unsigned BasicVectorSize = TII->getBasicVecRegSize();
-  // Should not coalesce if copying from bigger source.
-  if (SrcSize < DstSize &&
-      (SrcSize >= BasicVectorSize || DstSize >= BasicVectorSize)) {
-    LiveInterval &LI = LIS.getInterval(MI->getOperand(1).getReg());
-    const MachineInstr *FirstMI =
-        LI.empty() ? nullptr : LIS.getInstructionFromIndex(LI.beginIndex());
-    const MachineInstr *LastMI =
-        LI.empty() ? nullptr : LIS.getInstructionFromIndex(LI.endIndex());
-    // Coalescing inside the same basic block found beneficial. So, check that
-    // the LiveInterval is not just local to MBB.
-    if (!FirstMI || FirstMI->getParent() != MBB || !LastMI ||
-        LastMI->getParent() != MBB)
-      return false;
-  }
-
   return TargetRegisterInfo::shouldCoalesce(MI, SrcRC, SubReg, DstRC, DstSubReg,
                                             NewRC, LIS);
 }