Reapply r77654 with a fix: MachineFunctionPass's getAnalysisUsage
shouldn't do AU.setPreservesCFG(), because even though CodeGen passes
don't modify the LLVM IR CFG, they may modify the MachineFunction CFG,
and passes like MachineLoop are registered with isCFGOnly set to true.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@77691 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/CodeGen/LLVMTargetMachine.cpp b/lib/CodeGen/LLVMTargetMachine.cpp
index 0f33ee3..6f0581a 100644
--- a/lib/CodeGen/LLVMTargetMachine.cpp
+++ b/lib/CodeGen/LLVMTargetMachine.cpp
@@ -18,6 +18,7 @@
 #include "llvm/Analysis/LoopPass.h"
 #include "llvm/CodeGen/Passes.h"
 #include "llvm/CodeGen/GCStrategy.h"
+#include "llvm/CodeGen/MachineFunctionAnalysis.h"
 #include "llvm/Target/TargetOptions.h"
 #include "llvm/Target/TargetAsmInfo.h"
 #include "llvm/Target/TargetRegistry.h"
@@ -118,9 +119,6 @@
 
   PM.add(createGCInfoDeleter());
 
-  // Delete machine code for this function
-  PM.add(createMachineCodeDeleter());
-
   return false; // success!
 }
 
@@ -137,9 +135,6 @@
 
   PM.add(createGCInfoDeleter());
 
-  // Delete machine code for this function
-  PM.add(createMachineCodeDeleter());
-
   return false; // success!
 }
 
@@ -156,9 +151,6 @@
 
   PM.add(createGCInfoDeleter());
 
-  // Delete machine code for this function
-  PM.add(createMachineCodeDeleter());
-
   return false; // success!
 }
 
@@ -184,9 +176,6 @@
 
   PM.add(createGCInfoDeleter());
 
-  // Delete machine code for this function
-  PM.add(createMachineCodeDeleter());
-
   return false; // success!
 }
 
@@ -212,9 +201,6 @@
 
   PM.add(createGCInfoDeleter());
 
-  // Delete machine code for this function
-  PM.add(createMachineCodeDeleter());
-
   return false; // success!
 }
 
@@ -265,6 +251,9 @@
 
   // Standard Lower-Level Passes.
 
+  // Set up a MachineFunction for the rest of CodeGen to work on.
+  PM.add(new MachineFunctionAnalysis(*this, OptLevel));
+
   // Enable FastISel with -fast, but allow that to be overridden.
   if (EnableFastISelOption == cl::BOU_TRUE ||
       (OptLevel == CodeGenOpt::None && EnableFastISelOption != cl::BOU_FALSE))
diff --git a/lib/CodeGen/LiveVariables.cpp b/lib/CodeGen/LiveVariables.cpp
index bb72d80..2034566 100644
--- a/lib/CodeGen/LiveVariables.cpp
+++ b/lib/CodeGen/LiveVariables.cpp
@@ -48,6 +48,7 @@
 void LiveVariables::getAnalysisUsage(AnalysisUsage &AU) const {
   AU.addRequiredID(UnreachableMachineBlockElimID);
   AU.setPreservesAll();
+  MachineFunctionPass::getAnalysisUsage(AU);
 }
 
 void LiveVariables::VarInfo::dump() const {
diff --git a/lib/CodeGen/MachineFunction.cpp b/lib/CodeGen/MachineFunction.cpp
index 98396ee..aa3cfe2 100644
--- a/lib/CodeGen/MachineFunction.cpp
+++ b/lib/CodeGen/MachineFunction.cpp
@@ -36,15 +36,6 @@
 #include <sstream>
 using namespace llvm;
 
-bool MachineFunctionPass::runOnFunction(Function &F) {
-  // Do not codegen any 'available_externally' functions at all, they have
-  // definitions outside the translation unit.
-  if (F.hasAvailableExternallyLinkage())
-    return false;
-  
-  return runOnMachineFunction(MachineFunction::get(&F));
-}
-
 namespace {
   struct VISIBILITY_HIDDEN Printer : public MachineFunctionPass {
     static char ID;
@@ -59,6 +50,7 @@
 
     virtual void getAnalysisUsage(AnalysisUsage &AU) const {
       AU.setPreservesAll();
+      MachineFunctionPass::getAnalysisUsage(AU);
     }
 
     bool runOnMachineFunction(MachineFunction &MF) {
@@ -78,31 +70,6 @@
   return new Printer(OS, Banner);
 }
 
-namespace {
-  struct VISIBILITY_HIDDEN Deleter : public MachineFunctionPass {
-    static char ID;
-    Deleter() : MachineFunctionPass(&ID) {}
-
-    const char *getPassName() const { return "Machine Code Deleter"; }
-
-    bool runOnMachineFunction(MachineFunction &MF) {
-      // Delete the annotation from the function now.
-      MachineFunction::destruct(MF.getFunction());
-      return true;
-    }
-  };
-  char Deleter::ID = 0;
-}
-
-/// MachineCodeDeletion Pass - This pass deletes all of the machine code for
-/// the current function, which should happen after the function has been
-/// emitted to a .s file or to memory.
-FunctionPass *llvm::createMachineCodeDeleter() {
-  return new Deleter();
-}
-
-
-
 //===---------------------------------------------------------------------===//
 // MachineFunction implementation
 //===---------------------------------------------------------------------===//
@@ -111,7 +78,7 @@
   MBB->getParent()->DeleteMachineBasicBlock(MBB);
 }
 
-MachineFunction::MachineFunction(const Function *F,
+MachineFunction::MachineFunction(Function *F,
                                  const TargetMachine &TM)
   : Annotation(AnnotationManager::getID("CodeGen::MachineCodeForFunction")),
     Fn(F), Target(TM) {
@@ -356,42 +323,6 @@
 #endif // NDEBUG
 }
 
-// The next two methods are used to construct and to retrieve
-// the MachineCodeForFunction object for the given function.
-// construct() -- Allocates and initializes for a given function and target
-// get()       -- Returns a handle to the object.
-//                This should not be called before "construct()"
-//                for a given Function.
-//
-MachineFunction&
-MachineFunction::construct(const Function *Fn, const TargetMachine &Tar)
-{
-  AnnotationID MF_AID =
-                    AnnotationManager::getID("CodeGen::MachineCodeForFunction");
-  assert(Fn->getAnnotation(MF_AID) == 0 &&
-         "Object already exists for this function!");
-  MachineFunction* mcInfo = new MachineFunction(Fn, Tar);
-  Fn->addAnnotation(mcInfo);
-  return *mcInfo;
-}
-
-void MachineFunction::destruct(const Function *Fn) {
-  AnnotationID MF_AID =
-                    AnnotationManager::getID("CodeGen::MachineCodeForFunction");
-  bool Deleted = Fn->deleteAnnotation(MF_AID);
-  assert(Deleted && "Machine code did not exist for function!"); 
-  Deleted = Deleted; // silence warning when no assertions.
-}
-
-MachineFunction& MachineFunction::get(const Function *F)
-{
-  AnnotationID MF_AID =
-                    AnnotationManager::getID("CodeGen::MachineCodeForFunction");
-  MachineFunction *mc = (MachineFunction*)F->getAnnotation(MF_AID);
-  assert(mc && "Call construct() method first to allocate the object");
-  return *mc;
-}
-
 /// addLiveIn - Add the specified physical register as a live-in value and
 /// create a corresponding virtual register for it.
 unsigned MachineFunction::addLiveIn(unsigned PReg,
diff --git a/lib/CodeGen/MachineFunctionAnalysis.cpp b/lib/CodeGen/MachineFunctionAnalysis.cpp
new file mode 100644
index 0000000..8b7dba8
--- /dev/null
+++ b/lib/CodeGen/MachineFunctionAnalysis.cpp
@@ -0,0 +1,45 @@
+//===-- MachineFunctionAnalysis.cpp ---------------------------------------===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+// This file contains the definitions of the MachineFunctionAnalysis members.
+//
+//===----------------------------------------------------------------------===//
+
+#include "llvm/CodeGen/MachineFunctionAnalysis.h"
+#include "llvm/CodeGen/MachineFunction.h"
+using namespace llvm;
+
+// Register this pass with PassInfo directly to avoid having to define
+// a default constructor.
+static PassInfo
+X("Machine Function Analysis", "machine-function-analysis",
+  intptr_t(&MachineFunctionAnalysis::ID), 0,
+  /*CFGOnly=*/false, /*is_analysis=*/true);
+
+char MachineFunctionAnalysis::ID = 0;
+
+MachineFunctionAnalysis::MachineFunctionAnalysis(TargetMachine &tm,
+                                                 CodeGenOpt::Level OL) :
+  FunctionPass(&ID), TM(tm), OptLevel(OL), MF(0) {
+}
+
+bool MachineFunctionAnalysis::runOnFunction(Function &F) {
+  assert(!MF && "MachineFunctionAnalysis already initialized!");
+  MF = new MachineFunction(&F, TM);
+  return false;
+}
+
+void MachineFunctionAnalysis::releaseMemory() {
+  delete MF;
+  MF = 0;
+}
+
+void MachineFunctionAnalysis::getAnalysisUsage(AnalysisUsage &AU) const {
+  AU.setPreservesAll();
+}
diff --git a/lib/CodeGen/MachineFunctionPass.cpp b/lib/CodeGen/MachineFunctionPass.cpp
new file mode 100644
index 0000000..09f156a
--- /dev/null
+++ b/lib/CodeGen/MachineFunctionPass.cpp
@@ -0,0 +1,52 @@
+//===-- MachineFunctionPass.cpp -------------------------------------------===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+// This file contains the definitions of the MachineFunctionPass members.
+//
+//===----------------------------------------------------------------------===//
+
+#include "llvm/Analysis/AliasAnalysis.h"
+#include "llvm/Analysis/ScalarEvolution.h"
+#include "llvm/Analysis/IVUsers.h"
+#include "llvm/Analysis/LiveValues.h"
+#include "llvm/Analysis/LoopDependenceAnalysis.h"
+#include "llvm/Analysis/MemoryDependenceAnalysis.h"
+#include "llvm/CodeGen/MachineFunctionAnalysis.h"
+#include "llvm/CodeGen/MachineFunctionPass.h"
+using namespace llvm;
+
+bool MachineFunctionPass::runOnFunction(Function &F) {
+  // Do not codegen any 'available_externally' functions at all, they have
+  // definitions outside the translation unit.
+  if (F.hasAvailableExternallyLinkage())
+    return false;
+
+  MachineFunction &MF = getAnalysis<MachineFunctionAnalysis>().getMF();
+  return runOnMachineFunction(MF);
+}
+
+void MachineFunctionPass::getAnalysisUsage(AnalysisUsage &AU) const {
+  AU.addRequired<MachineFunctionAnalysis>();
+  AU.addPreserved<MachineFunctionAnalysis>();
+
+  // MachineFunctionPass preserves all LLVM IR passes, but there's no
+  // high-level way to express this. Instead, just list a bunch of
+  // passes explicitly.
+  AU.addPreserved<AliasAnalysis>();
+  AU.addPreserved<ScalarEvolution>();
+  AU.addPreserved<IVUsers>();
+  AU.addPreserved<LoopDependenceAnalysis>();
+  AU.addPreserved<MemoryDependenceAnalysis>();
+  AU.addPreserved<LiveValues>();
+  AU.addPreserved<DominatorTree>();
+  AU.addPreserved<DominanceFrontier>();
+  AU.addPreserved<LoopInfo>();
+
+  FunctionPass::getAnalysisUsage(AU);
+}
diff --git a/lib/CodeGen/MachineLoopInfo.cpp b/lib/CodeGen/MachineLoopInfo.cpp
index a5694ae..2da8e37 100644
--- a/lib/CodeGen/MachineLoopInfo.cpp
+++ b/lib/CodeGen/MachineLoopInfo.cpp
@@ -41,4 +41,5 @@
 void MachineLoopInfo::getAnalysisUsage(AnalysisUsage &AU) const {
   AU.setPreservesAll();
   AU.addRequired<MachineDominatorTree>();
+  MachineFunctionPass::getAnalysisUsage(AU);
 }
diff --git a/lib/CodeGen/MachineVerifier.cpp b/lib/CodeGen/MachineVerifier.cpp
index d9c37de..a13d39e 100644
--- a/lib/CodeGen/MachineVerifier.cpp
+++ b/lib/CodeGen/MachineVerifier.cpp
@@ -55,6 +55,7 @@
 
     void getAnalysisUsage(AnalysisUsage &AU) const {
       AU.setPreservesAll();
+      MachineFunctionPass::getAnalysisUsage(AU);
     }
 
     bool runOnMachineFunction(MachineFunction &MF);
diff --git a/lib/CodeGen/PrologEpilogInserter.cpp b/lib/CodeGen/PrologEpilogInserter.cpp
index 5aa37c9..9d5c55b 100644
--- a/lib/CodeGen/PrologEpilogInserter.cpp
+++ b/lib/CodeGen/PrologEpilogInserter.cpp
@@ -111,7 +111,6 @@
 
 #if 0
 void PEI::getAnalysisUsage(AnalysisUsage &AU) const {
-  AU.setPreservesCFG();
   if (ShrinkWrapping || ShrinkWrapFunc != "") {
     AU.addRequired<MachineLoopInfo>();
     AU.addRequired<MachineDominatorTree>();
diff --git a/lib/CodeGen/SelectionDAG/SelectionDAGISel.cpp b/lib/CodeGen/SelectionDAG/SelectionDAGISel.cpp
index ab87449..1072c95 100644
--- a/lib/CodeGen/SelectionDAG/SelectionDAGISel.cpp
+++ b/lib/CodeGen/SelectionDAG/SelectionDAGISel.cpp
@@ -29,6 +29,7 @@
 #include "llvm/CodeGen/GCStrategy.h"
 #include "llvm/CodeGen/GCMetadata.h"
 #include "llvm/CodeGen/MachineFunction.h"
+#include "llvm/CodeGen/MachineFunctionAnalysis.h"
 #include "llvm/CodeGen/MachineFrameInfo.h"
 #include "llvm/CodeGen/MachineInstrBuilder.h"
 #include "llvm/CodeGen/MachineJumpTableInfo.h"
@@ -267,7 +268,7 @@
 //===----------------------------------------------------------------------===//
 
 SelectionDAGISel::SelectionDAGISel(TargetMachine &tm, CodeGenOpt::Level OL) :
-  FunctionPass(&ID), TM(tm), TLI(*tm.getTargetLowering()),
+  MachineFunctionPass(&ID), TM(tm), TLI(*tm.getTargetLowering()),
   FuncInfo(new FunctionLoweringInfo(TLI)),
   CurDAG(new SelectionDAG(TLI, *FuncInfo)),
   SDL(new SelectionDAGLowering(*CurDAG, TLI, *FuncInfo, OL)),
@@ -291,9 +292,12 @@
   AU.addRequired<GCModuleInfo>();
   AU.addRequired<DwarfWriter>();
   AU.setPreservesAll();
+  MachineFunctionPass::getAnalysisUsage(AU);
 }
 
-bool SelectionDAGISel::runOnFunction(Function &Fn) {
+bool SelectionDAGISel::runOnMachineFunction(MachineFunction &mf) {
+  Function &Fn = *mf.getFunction();
+
   // Do some sanity-checking on the command-line options.
   assert((!EnableFastISelVerbose || EnableFastISel) &&
          "-fast-isel-verbose requires -fast-isel");
@@ -305,12 +309,11 @@
   if (Fn.hasAvailableExternallyLinkage())
     return false;
 
-
   // Get alias analysis for load/store combining.
   AA = &getAnalysis<AliasAnalysis>();
 
   TargetMachine &TM = TLI.getTargetMachine();
-  MF = &MachineFunction::construct(&Fn, TM);
+  MF = &mf;
   const TargetInstrInfo &TII = *TM.getInstrInfo();
   const TargetRegisterInfo &TRI = *TM.getRegisterInfo();