[CodeGen] Remove unused forward declarations (NFC)

llvm/include/llvm/CodeGen/DbgEntityHistoryCalculator.h

@@ -17,7 +17,6 @@
 
 namespace llvm {
 
-class DILocalVariable;
 class DILocation;
 class DINode;
 class MachineFunction;

llvm/include/llvm/CodeGen/FaultMaps.h

@@ -18,7 +18,6 @@ namespace llvm {
 
 class AsmPrinter;
 class MCExpr;
-class raw_ostream;
 
 class FaultMaps {
 public:

llvm/include/llvm/CodeGen/GlobalISel/CombinerInfo.h

@@ -20,7 +20,6 @@ class GISelChangeObserver;
 class LegalizerInfo;
 class MachineInstr;
 class MachineIRBuilder;
-class MachineRegisterInfo;
 
 // Contains information relevant to enabling/disabling various combines for a
 // pass.

llvm/include/llvm/CodeGen/GlobalISel/GISelWorkList.h

@@ -15,7 +15,6 @@
 namespace llvm {
 
 class MachineInstr;
-class MachineFunction;
 
 // Worklist which mostly works similar to InstCombineWorkList, but on
 // MachineInstrs. The main difference with something like a SetVector is that

llvm/include/llvm/CodeGen/GlobalISel/Legalizer.h

@@ -25,7 +25,6 @@
 
 namespace llvm {
 
-class MachineRegisterInfo;
 class LostDebugLocObserver;
 
 class Legalizer : public MachineFunctionPass {

llvm/include/llvm/CodeGen/GlobalISel/LegalizerHelper.h

@@ -30,7 +30,6 @@
 namespace llvm {
 // Forward declarations.
 class LegalizerInfo;
-class Legalizer;
 class MachineRegisterInfo;
 class GISelChangeObserver;
 class LostDebugLocObserver;

llvm/include/llvm/CodeGen/GlobalISel/LegalizerInfo.h

@@ -38,7 +38,6 @@ class LegalizerHelper;
 class MachineInstr;
 class MachineRegisterInfo;
 class MCInstrInfo;
-class GISelChangeObserver;
 
 namespace LegalizeActions {
 enum LegalizeAction : std::uint8_t {

llvm/include/llvm/CodeGen/GlobalISel/LoadStoreOpt.h

@@ -30,7 +30,6 @@
 namespace llvm {
 // Forward declarations.
 class MachineRegisterInfo;
-class TargetTransformInfo;
 namespace GISelAddressing {
 /// Helper struct to store a base, index and offset that forms an address
 struct BaseIndexOffset {

llvm/include/llvm/CodeGen/GlobalISel/Utils.h

@@ -44,7 +44,6 @@ class TargetLowering;
 class TargetPassConfig;
 class TargetRegisterInfo;
 class TargetRegisterClass;
-class ConstantInt;
 class ConstantFP;
 class APFloat;
 class MachineIRBuilder;

llvm/include/llvm/CodeGen/LiveRangeEdit.h

@@ -34,9 +34,7 @@ namespace llvm {
 
 class AAResults;
 class LiveIntervals;
-class MachineBlockFrequencyInfo;
 class MachineInstr;
-class MachineLoopInfo;
 class MachineOperand;
 class TargetInstrInfo;
 class TargetRegisterInfo;

llvm/include/llvm/CodeGen/MachineLoopUtils.h

@@ -10,7 +10,6 @@
 #define LLVM_CODEGEN_MACHINELOOPUTILS_H
 
 namespace llvm {
-class MachineLoop;
 class MachineBasicBlock;
 class MachineRegisterInfo;
 class TargetInstrInfo;

llvm/include/llvm/CodeGen/MachineModuleInfo.h

@@ -44,7 +44,6 @@
 namespace llvm {
 
 class BasicBlock;
-class CallInst;
 class Function;
 class LLVMTargetMachine;
 class MMIAddrLabelMap;

llvm/include/llvm/CodeGen/Passes.h

@@ -30,7 +30,6 @@ class MemoryBuffer;
 class ModulePass;
 class Pass;
 class TargetMachine;
-class TargetRegisterClass;
 class raw_ostream;
 
 } // End llvm namespace

llvm/include/llvm/CodeGen/TailDuplicator.h

@@ -26,7 +26,6 @@
 namespace llvm {
 
 class MachineBasicBlock;
-class MachineBlockFrequencyInfo;
 class MachineBranchProbabilityInfo;
 class MachineFunction;
 class MachineInstr;

llvm/include/llvm/CodeGen/TargetLowering.h

@@ -63,7 +63,6 @@
 
 namespace llvm {
 
-class BranchProbability;
 class CCState;
 class CCValAssign;
 class Constant;