llvm-6502/lib/CodeGen/LiveStackAnalysis.cpp
Chandler Carruth 8677f2ff9a [Modules] Remove potential ODR violations by sinking the DEBUG_TYPE
define below all header includes in the lib/CodeGen/... tree. While the
current modules implementation doesn't check for this kind of ODR
violation yet, it is likely to grow support for it in the future. It
also removes one layer of macro pollution across all the included
headers.

Other sub-trees will follow.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@206837 91177308-0d34-0410-b5e6-96231b3b80d8
2014-04-22 02:02:50 +00:00

88 lines
2.9 KiB
C++

//===-- 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.
//
//===----------------------------------------------------------------------===//
#include "llvm/CodeGen/LiveStackAnalysis.h"
#include "llvm/ADT/Statistic.h"
#include "llvm/CodeGen/LiveIntervalAnalysis.h"
#include "llvm/CodeGen/Passes.h"
#include "llvm/Support/Debug.h"
#include "llvm/Support/raw_ostream.h"
#include "llvm/Target/TargetRegisterInfo.h"
#include <limits>
using namespace llvm;
#define DEBUG_TYPE "livestacks"
char LiveStacks::ID = 0;
INITIALIZE_PASS_BEGIN(LiveStacks, "livestacks",
"Live Stack Slot Analysis", false, false)
INITIALIZE_PASS_DEPENDENCY(SlotIndexes)
INITIALIZE_PASS_END(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";
}
}