[llvm-exegesis][NFC] Remove dead code.

[courbet]

Summary

hasAliasingImplicitRegistersThrough() is no longer used.

[gchatelet]

Thx!

llvm/tools/llvm-exegesis/lib/MCInstrDescView.h

struct Instruction {
   bool hasAliasingImplicitRegisters() const;
 
   // Whether this instruction is self aliasing through some registers.
   // Repeating this instruction may execute sequentially by picking aliasing
   // Use and Def registers. It may also execute in parallel by picking non
   // aliasing Use and Def registers.
   bool hasAliasingRegisters() const;
 
-  // Whether this instruction's implicit registers alias with OtherInstr's
-  // implicit registers.
-  bool hasAliasingImplicitRegistersThrough(const Instruction &OtherInstr) const;
-
   // Whether this instruction's registers alias with OtherInstr's registers.
   bool hasAliasingRegistersThrough(const Instruction &OtherInstr) const;
 
   // Returns whether this instruction has Memory Operands.
   // Repeating this instruction executes sequentially with an instruction that
   // reads or write the same memory region.
   bool hasMemoryOperands() const;
 

llvm/tools/llvm-exegesis/lib/MCInstrDescView.cpp

return any_of(Operands, [](const Operand &Op) {
     return Op.isReg() && Op.isExplicit() && Op.isMemory();
   });
 }
 
 bool Instruction::hasAliasingImplicitRegisters() const {
   return ImplDefRegs.anyCommon(ImplUseRegs);
 }
 
-bool Instruction::hasAliasingImplicitRegistersThrough(
-    const Instruction &OtherInstr) const {
-  return ImplDefRegs.anyCommon(OtherInstr.ImplUseRegs) &&
-         OtherInstr.ImplDefRegs.anyCommon(ImplUseRegs);
-}
-
 bool Instruction::hasAliasingRegistersThrough(
     const Instruction &OtherInstr) const {
   return AllDefRegs.anyCommon(OtherInstr.AllUseRegs) &&
          OtherInstr.AllDefRegs.anyCommon(AllUseRegs);
 }
 
 bool Instruction::hasTiedRegisters() const {
   return llvm::any_of(