Revert "[AArch64][GlobalISel] Optimize conjunctions of compares to conditional compares."

This reverts commit 2a46450.

This triggers the following assertion in an internal project:

    Assertion failed: (VRegInfo[Reg.id()].first.is<const TargetRegisterClass
    *>() && "Register class not set, wrong accessor"), function getRegClass,
    file MachineRegisterInfo.h, line 646.

I'll work with the author directly to get a reproducer.

Author: fhahn

llvm/include/llvm/CodeGen/GlobalISel/GenericMachineInstrs.h

@@ -14,7 +14,6 @@
 #ifndef LLVM_CODEGEN_GLOBALISEL_GENERICMACHINEINSTRS_H
 #define LLVM_CODEGEN_GLOBALISEL_GENERICMACHINEINSTRS_H
 
-#include "llvm/IR/Instructions.h"
 #include "llvm/CodeGen/MachineInstr.h"
 #include "llvm/CodeGen/MachineMemOperand.h"
 #include "llvm/CodeGen/TargetOpcodes.h"
@@ -227,37 +226,6 @@ class GSelect : public GenericMachineInstr {
   }
 };
 
-/// Represent a G_ICMP or G_FCMP.
-class GAnyCmp : public GenericMachineInstr {
-public:
-  CmpInst::Predicate getCond() const {
-    return static_cast<CmpInst::Predicate>(getOperand(1).getPredicate());
-  }
-  Register getLHSReg() const { return getReg(2); }
-  Register getRHSReg() const { return getReg(3); }
-
-  static bool classof(const MachineInstr *MI) {
-    return MI->getOpcode() == TargetOpcode::G_ICMP ||
-           MI->getOpcode() == TargetOpcode::G_FCMP;
-  }
-};
-
-/// Represent a G_ICMP.
-class GICmp : public GAnyCmp {
-public:
-  static bool classof(const MachineInstr *MI) {
-    return MI->getOpcode() == TargetOpcode::G_ICMP;
-  }
-};
-
-/// Represent a G_FCMP.
-class GFCmp : public GAnyCmp {
-public:
-  static bool classof(const MachineInstr *MI) {
-    return MI->getOpcode() == TargetOpcode::G_FCMP;
-  }
-};
-
 } // namespace llvm
 
 #endif // LLVM_CODEGEN_GLOBALISEL_GENERICMACHINEINSTRS_H