1 files changed, 83 insertions, 0 deletions
diff --git a/contrib/llvm/lib/CodeGen/LiveStackAnalysis.cpp b/contrib/llvm/lib/CodeGen/LiveStackAnalysis.cpp
new file mode 100644
index 0000000..939e795
--- /dev/null
+++ b/contrib/llvm/lib/CodeGen/LiveStackAnalysis.cpp
@@ -0,0 +1,83 @@
+//===-- LiveStackAnalysis.cpp - Live Stack Slot Analysis ------------------===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+// This file implements the live stack slot analysis pass. It is analogous to
+// live interval analysis except it's analyzing liveness of stack slots rather
+// than registers.
+//
+//===----------------------------------------------------------------------===//
+
+#define DEBUG_TYPE "livestacks"
+#include "llvm/CodeGen/LiveStackAnalysis.h"
+#include "llvm/CodeGen/LiveIntervalAnalysis.h"
+#include "llvm/CodeGen/Passes.h"
+#include "llvm/Target/TargetRegisterInfo.h"
+#include "llvm/Support/Debug.h"
+#include "llvm/Support/raw_ostream.h"
+#include "llvm/ADT/Statistic.h"
+#include <limits>
+using namespace llvm;
+
+char LiveStacks::ID = 0;
+INITIALIZE_PASS(LiveStacks, "livestacks",
+                "Live Stack Slot Analysis", false, false)
+
+char &llvm::LiveStacksID = LiveStacks::ID;
+
+void LiveStacks::getAnalysisUsage(AnalysisUsage &AU) const {
+  AU.setPreservesAll();
+  AU.addPreserved<SlotIndexes>();
+  AU.addRequiredTransitive<SlotIndexes>();
+  MachineFunctionPass::getAnalysisUsage(AU);
+}
+
+void LiveStacks::releaseMemory() {
+  // Release VNInfo memory regions, VNInfo objects don't need to be dtor'd.
+  VNInfoAllocator.Reset();
+  S2IMap.clear();
+  S2RCMap.clear();
+}
+
+bool LiveStacks::runOnMachineFunction(MachineFunction &MF) {
+  TRI = MF.getTarget().getRegisterInfo();
+  // FIXME: No analysis is being done right now. We are relying on the
+  // register allocators to provide the information.
+  return false;
+}
+
+LiveInterval &
+LiveStacks::getOrCreateInterval(int Slot, const TargetRegisterClass *RC) {
+  assert(Slot >= 0 && "Spill slot indice must be >= 0");
+  SS2IntervalMap::iterator I = S2IMap.find(Slot);
+  if (I == S2IMap.end()) {
+    I = S2IMap.insert(I, std::make_pair(Slot,
+            LiveInterval(TargetRegisterInfo::index2StackSlot(Slot), 0.0F)));
+    S2RCMap.insert(std::make_pair(Slot, RC));
+  } else {
+    // Use the largest common subclass register class.
+    const TargetRegisterClass *OldRC = S2RCMap[Slot];
+    S2RCMap[Slot] = TRI->getCommonSubClass(OldRC, RC);
+  }
+  return I->second;
+}
+
+/// print - Implement the dump method.
+void LiveStacks::print(raw_ostream &OS, const Module*) const {
+
+  OS << "********** INTERVALS **********\n";
+  for (const_iterator I = begin(), E = end(); I != E; ++I) {
+    I->second.print(OS);
+    int Slot = I->first;
+    const TargetRegisterClass *RC = getIntervalRegClass(Slot);
+    if (RC)
+      OS << " [" << RC->getName() << "]\n";
+    else
+      OS << " [Unknown]\n";
+  }
+}