TargetSubtargetInfo: Move implementation to lib/CodeGen; NFC

[MatzeB]

Summary

Nowadays TargetSubtargetInfo is filled with CodeGen specific interfaces
like getInstrInfo(), getFrameLowering(), getSelectionDAGInfo(), ... also most
of the tuning flags like enablePostRAScheduler(), getAntiDepBreakMode(),
enableRALocalReassignment(), ... are tweaked and tested with CodeGen only so it
is very unlikely this interface will ever be used outside of CodeGen.

Moving the class into CodeGen allows to provide a default
implementation of an interface that calls CodeGen functions. I plan to
use this in an upcoming commit.

[chandlerc]

If you want to do this, we should really move the header as well. We shouldn't have classes with headers in Target and implementation in CodeGen.

However, I suspect that will present more problems... =/

[MatzeB]

In D26948#602134, @chandlerc wrote:

If you want to do this, we should really move the header as well. We shouldn't have classes with headers in Target and implementation in CodeGen.

However, I suspect that will present more problems... =/

Well
include/llvm/Target/TargetRegisterInfo.h
include/llvm/Target/TargetFrameLowering.h
include/llvm/Target/TargetInstrInfo.h
...
are all implemented in lib/CodeGen as well, so I thought I stay consistent (even though it is silly).

[chandlerc]

Sure. What's one more.

[echristo]

Chandler said he was going to look into completing moves based on this later so as an incremental step this is definitely ok.

Thanks!

-eric

lib/CodeGen/CMakeLists.txt

add_llvm_library(LLVMCodeGen
   TargetFrameLoweringImpl.cpp
   TargetInstrInfo.cpp
   TargetLoweringBase.cpp
   TargetLoweringObjectFileImpl.cpp
   TargetOptionsImpl.cpp
   TargetPassConfig.cpp
   TargetRegisterInfo.cpp
   TargetSchedule.cpp
+  TargetSubtargetInfo.cpp
   TwoAddressInstructionPass.cpp
   UnreachableBlockElim.cpp
   VirtRegMap.cpp
   WinEHPrepare.cpp
   XRayInstrumentation.cpp
 
   ADDITIONAL_HEADER_DIRS
   ${LLVM_MAIN_INCLUDE_DIR}/llvm/CodeGen

lib/CodeGen/TargetSubtargetInfo.cpp

 //===-- TargetSubtargetInfo.cpp - General Target Information ---------------==//
 //
 //                     The LLVM Compiler Infrastructure
 //
 // This file is distributed under the University of Illinois Open Source
 // License. See LICENSE.TXT for details.
 //
 //===----------------------------------------------------------------------===//
 //
-// This file describes the general parts of a Subtarget.
+/// \file This file describes the general parts of a Subtarget.
 //
 //===----------------------------------------------------------------------===//
 
 #include "llvm/Target/TargetSubtargetInfo.h"
 using namespace llvm;
 
 //---------------------------------------------------------------------------
 // TargetSubtargetInfo Class

lib/Target/CMakeLists.txt

 list(APPEND LLVM_COMMON_DEPENDS intrinsics_gen)
 
 add_llvm_library(LLVMTarget
   Target.cpp
   TargetIntrinsicInfo.cpp
   TargetLoweringObjectFile.cpp
   TargetMachine.cpp
   TargetMachineC.cpp
-  TargetSubtargetInfo.cpp
 
   ADDITIONAL_HEADER_DIRS
   ${LLVM_MAIN_INCLUDE_DIR}/llvm/Target
   )
 
 foreach(t ${LLVM_TARGETS_TO_BUILD})
   message(STATUS "Targeting ${t}")
   add_subdirectory(${t})
 endforeach()