Revert r279564. It introduces undefined behavior (binding a reference to a

dereferenced null pointer) in MachineModuleInfo::MachineModuleInfo that causes
-Werror builds (including several buildbots) to fail.

llvm-svn: 279580

1 files changed, 62 insertions, 0 deletions

diff --git a/llvm/lib/CodeGen/MachineFunctionAnalysis.cpp b/llvm/lib/CodeGen/MachineFunctionAnalysis.cpp
new file mode 100644
index 00000000000..3b69ed55fb6
--- /dev/null
+++ b/llvm/lib/CodeGen/MachineFunctionAnalysis.cpp
@@ -0,0 +1,62 @@
+//===-- 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/GCMetadata.h"
+#include "llvm/CodeGen/MachineFunction.h"
+#include "llvm/CodeGen/MachineModuleInfo.h"
+#include "llvm/CodeGen/MachineFunctionInitializer.h"
+using namespace llvm;
+
+char MachineFunctionAnalysis::ID = 0;
+
+MachineFunctionAnalysis::MachineFunctionAnalysis(
+    const TargetMachine &tm, MachineFunctionInitializer *MFInitializer)
+    : FunctionPass(ID), TM(tm), MF(nullptr), MFInitializer(MFInitializer) {
+  initializeMachineModuleInfoPass(*PassRegistry::getPassRegistry());
+}
+
+MachineFunctionAnalysis::~MachineFunctionAnalysis() {
+  releaseMemory();
+  assert(!MF && "MachineFunctionAnalysis left initialized!");
+}
+
+void MachineFunctionAnalysis::getAnalysisUsage(AnalysisUsage &AU) const {
+  AU.setPreservesAll();
+  AU.addRequired<MachineModuleInfo>();
+}
+
+bool MachineFunctionAnalysis::doInitialization(Module &M) {
+  MachineModuleInfo *MMI = getAnalysisIfAvailable<MachineModuleInfo>();
+  assert(MMI && "MMI not around yet??");
+  MMI->setModule(&M);
+  NextFnNum = 0;
+  return false;
+}
+
+
+bool MachineFunctionAnalysis::runOnFunction(Function &F) {
+  assert(!MF && "MachineFunctionAnalysis already initialized!");
+  MF = new MachineFunction(&F, TM, NextFnNum++,
+                           getAnalysis<MachineModuleInfo>());
+  if (MFInitializer) {
+    if (MFInitializer->initializeMachineFunction(*MF))
+      report_fatal_error("Unable to initialize machine function");
+  }
+  return false;
+}
+
+void MachineFunctionAnalysis::releaseMemory() {
+  delete MF;
+  MF = nullptr;
+}