Check in LLVM r95781.

1 files changed, 63 insertions, 0 deletions

diff --git a/lib/CodeGen/LiveStackAnalysis.cpp b/lib/CodeGen/LiveStackAnalysis.cpp
new file mode 100644
index 0000000..d2f3775
--- /dev/null
+++ b/lib/CodeGen/LiveStackAnalysis.cpp
@@ -0,0 +1,63 @@
+//===-- 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;
+static RegisterPass<LiveStacks> X("livestacks", "Live Stack Slot Analysis");
+
+void LiveStacks::getAnalysisUsage(AnalysisUsage &AU) const {
+  AU.setPreservesAll();
+  AU.addPreserved<SlotIndexes>();
+  AU.addRequiredTransitive<SlotIndexes>();
+  MachineFunctionPass::getAnalysisUsage(AU);
+}
+
+void LiveStacks::releaseMemory() {
+  // Release VNInfo memroy regions after all VNInfo objects are dtor'd.
+  VNInfoAllocator.Reset();
+  S2IMap.clear();
+  S2RCMap.clear();
+}
+
+bool LiveStacks::runOnMachineFunction(MachineFunction &) {
+  // FIXME: No analysis is being done right now. We are relying on the
+  // register allocators to provide the information.
+  return false;
+}
+
+/// 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";
+  }
+}