diff options
Diffstat (limited to 'contrib/llvm/lib/CodeGen/MachineLoopInfo.cpp')
-rw-r--r-- | contrib/llvm/lib/CodeGen/MachineLoopInfo.cpp | 81 |
1 files changed, 81 insertions, 0 deletions
diff --git a/contrib/llvm/lib/CodeGen/MachineLoopInfo.cpp b/contrib/llvm/lib/CodeGen/MachineLoopInfo.cpp new file mode 100644 index 0000000..4e2cfdc --- /dev/null +++ b/contrib/llvm/lib/CodeGen/MachineLoopInfo.cpp @@ -0,0 +1,81 @@ +//===- MachineLoopInfo.cpp - Natural Loop Calculator ----------------------===// +// +// The LLVM Compiler Infrastructure +// +// This file is distributed under the University of Illinois Open Source +// License. See LICENSE.TXT for details. +// +//===----------------------------------------------------------------------===// +// +// This file defines the MachineLoopInfo class that is used to identify natural +// loops and determine the loop depth of various nodes of the CFG. Note that +// the loops identified may actually be several natural loops that share the +// same header node... not just a single natural loop. +// +//===----------------------------------------------------------------------===// + +#include "llvm/CodeGen/MachineLoopInfo.h" +#include "llvm/Analysis/LoopInfoImpl.h" +#include "llvm/CodeGen/MachineDominators.h" +#include "llvm/CodeGen/Passes.h" +#include "llvm/Support/Debug.h" +using namespace llvm; + +// Explicitly instantiate methods in LoopInfoImpl.h for MI-level Loops. +template class llvm::LoopBase<MachineBasicBlock, MachineLoop>; +template class llvm::LoopInfoBase<MachineBasicBlock, MachineLoop>; + +char MachineLoopInfo::ID = 0; +INITIALIZE_PASS_BEGIN(MachineLoopInfo, "machine-loops", + "Machine Natural Loop Construction", true, true) +INITIALIZE_PASS_DEPENDENCY(MachineDominatorTree) +INITIALIZE_PASS_END(MachineLoopInfo, "machine-loops", + "Machine Natural Loop Construction", true, true) + +char &llvm::MachineLoopInfoID = MachineLoopInfo::ID; + +bool MachineLoopInfo::runOnMachineFunction(MachineFunction &) { + releaseMemory(); + LI.Analyze(getAnalysis<MachineDominatorTree>().getBase()); + return false; +} + +void MachineLoopInfo::getAnalysisUsage(AnalysisUsage &AU) const { + AU.setPreservesAll(); + AU.addRequired<MachineDominatorTree>(); + MachineFunctionPass::getAnalysisUsage(AU); +} + +MachineBasicBlock *MachineLoop::getTopBlock() { + MachineBasicBlock *TopMBB = getHeader(); + MachineFunction::iterator Begin = TopMBB->getParent()->begin(); + if (TopMBB != Begin) { + MachineBasicBlock *PriorMBB = prior(MachineFunction::iterator(TopMBB)); + while (contains(PriorMBB)) { + TopMBB = PriorMBB; + if (TopMBB == Begin) break; + PriorMBB = prior(MachineFunction::iterator(TopMBB)); + } + } + return TopMBB; +} + +MachineBasicBlock *MachineLoop::getBottomBlock() { + MachineBasicBlock *BotMBB = getHeader(); + MachineFunction::iterator End = BotMBB->getParent()->end(); + if (BotMBB != prior(End)) { + MachineBasicBlock *NextMBB = llvm::next(MachineFunction::iterator(BotMBB)); + while (contains(NextMBB)) { + BotMBB = NextMBB; + if (BotMBB == llvm::next(MachineFunction::iterator(BotMBB))) break; + NextMBB = llvm::next(MachineFunction::iterator(BotMBB)); + } + } + return BotMBB; +} + +#if !defined(NDEBUG) || defined(LLVM_ENABLE_DUMP) +void MachineLoop::dump() const { + print(dbgs()); +} +#endif |