1 //===-- LiveStackAnalysis.cpp - Live Stack Slot Analysis ------------------===//
3 // The LLVM Compiler Infrastructure
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
8 //===----------------------------------------------------------------------===//
10 // This file implements the live stack slot analysis pass. It is analogous to
11 // live interval analysis except it's analyzing liveness of stack slots rather
14 //===----------------------------------------------------------------------===//
16 #define DEBUG_TYPE "livestacks"
17 #include "llvm/CodeGen/LiveStackAnalysis.h"
18 #include "llvm/CodeGen/LiveIntervalAnalysis.h"
19 #include "llvm/CodeGen/Passes.h"
20 #include "llvm/Target/TargetRegisterInfo.h"
21 #include "llvm/Support/Debug.h"
22 #include "llvm/ADT/Statistic.h"
26 char LiveStacks::ID = 0;
27 static RegisterPass<LiveStacks> X("livestacks", "Live Stack Slot Analysis");
29 void LiveStacks::scaleNumbering(int factor) {
30 // Scale the intervals.
31 for (iterator LI = begin(), LE = end(); LI != LE; ++LI) {
32 LI->second.scaleNumbering(factor);
36 void LiveStacks::getAnalysisUsage(AnalysisUsage &AU) const {
38 MachineFunctionPass::getAnalysisUsage(AU);
41 void LiveStacks::releaseMemory() {
42 // Release VNInfo memroy regions after all VNInfo objects are dtor'd.
43 VNInfoAllocator.Reset();
48 bool LiveStacks::runOnMachineFunction(MachineFunction &) {
49 // FIXME: No analysis is being done right now. We are relying on the
50 // register allocators to provide the information.
54 /// print - Implement the dump method.
55 void LiveStacks::print(std::ostream &O, const Module*) const {
56 O << "********** INTERVALS **********\n";
57 for (const_iterator I = begin(), E = end(); I != E; ++I) {
60 const TargetRegisterClass *RC = getIntervalRegClass(Slot);
62 O << " [" << RC->getName() << "]\n";