CodeGen: Remove MachineFunctionAnalysis => Enable (Machine)ModulePasses

Re-apply this patch, hopefully I will get away without any warnings
in the constructor now.

This patch removes the MachineFunctionAnalysis. Instead we keep a
map from IR Function to MachineFunction in the MachineModuleInfo.

This allows the insertion of ModulePasses into the codegen pipeline
without breaking it because the MachineFunctionAnalysis gets dropped
before a module pass.

Peak memory should stay unchanged without a ModulePass in the codegen
pipeline: Previously the MachineFunction was freed at the end of a codegen
function pipeline because the MachineFunctionAnalysis was dropped; With
this patch the MachineFunction is freed after the AsmPrinter has
finished.

Differential Revision: http://reviews.llvm.org/D23736

llvm-svn: 279602
diff --git a/llvm/lib/Target/AMDGPU/AMDILCFGStructurizer.cpp b/llvm/lib/Target/AMDGPU/AMDILCFGStructurizer.cpp
index 64dcb45..e82c9ed 100644
--- a/llvm/lib/Target/AMDGPU/AMDILCFGStructurizer.cpp
+++ b/llvm/lib/Target/AMDGPU/AMDILCFGStructurizer.cpp
@@ -18,7 +18,6 @@
 #include "llvm/ADT/Statistic.h"
 #include "llvm/CodeGen/MachineDominators.h"
 #include "llvm/CodeGen/MachineFunction.h"
-#include "llvm/CodeGen/MachineFunctionAnalysis.h"
 #include "llvm/CodeGen/MachineFunctionPass.h"
 #include "llvm/CodeGen/MachineInstrBuilder.h"
 #include "llvm/CodeGen/MachineJumpTableInfo.h"
@@ -144,11 +143,10 @@
   }
 
   void getAnalysisUsage(AnalysisUsage &AU) const override {
-    AU.addPreserved<MachineFunctionAnalysis>();
-    AU.addRequired<MachineFunctionAnalysis>();
     AU.addRequired<MachineDominatorTree>();
     AU.addRequired<MachinePostDominatorTree>();
     AU.addRequired<MachineLoopInfo>();
+    MachineFunctionPass::getAnalysisUsage(AU);
   }
 
   /// Perform the CFG structurization