mirror of
https://github.com/RPCS3/llvm-mirror.git
synced 2024-11-23 11:13:28 +01:00
8ce897de05
This patch is a follow up from r240560 and is a step further into mitigating the compile time performance issues in CaptureTracker. By providing the CaptureTracker with a "cached ordered basic block" instead of computing it every time, MemDepAnalysis can use this cache throughout its calls to AA->callCapturesBefore, avoiding to recompute it for every scanned instruction. In the same testcase used in r240560, compile time is reduced from 2min to 30s. This also fixes PR22348. rdar://problem/19230319 Differential Revision: http://reviews.llvm.org/D11364 llvm-svn: 243750
67 lines
2.5 KiB
C++
67 lines
2.5 KiB
C++
//===- llvm/Analysis/OrderedBasicBlock.h --------------------- -*- C++ -*-===//
|
|
//
|
|
// 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 OrderedBasicBlock class. OrderedBasicBlock maintains
|
|
// an interface where clients can query if one instruction comes before another
|
|
// in a BasicBlock. Since BasicBlock currently lacks a reliable way to query
|
|
// relative position between instructions one can use OrderedBasicBlock to do
|
|
// such queries. OrderedBasicBlock is lazily built on a source BasicBlock and
|
|
// maintains an internal Instruction -> Position map. A OrderedBasicBlock
|
|
// instance should be discarded whenever the source BasicBlock changes.
|
|
//
|
|
// It's currently used by the CaptureTracker in order to find relative
|
|
// positions of a pair of instructions inside a BasicBlock.
|
|
//
|
|
//===----------------------------------------------------------------------===//
|
|
|
|
#ifndef LLVM_ANALYSIS_ORDEREDBASICBLOCK_H
|
|
#define LLVM_ANALYSIS_ORDEREDBASICBLOCK_H
|
|
|
|
#include "llvm/ADT/DenseMap.h"
|
|
#include "llvm/IR/BasicBlock.h"
|
|
|
|
namespace llvm {
|
|
|
|
class Instruction;
|
|
class BasicBlock;
|
|
|
|
class OrderedBasicBlock {
|
|
private:
|
|
/// \brief Map a instruction to its position in a BasicBlock.
|
|
SmallDenseMap<const Instruction *, unsigned, 32> NumberedInsts;
|
|
|
|
/// \brief Keep track of last instruction inserted into \p NumberedInsts.
|
|
/// It speeds up queries for uncached instructions by providing a start point
|
|
/// for new queries in OrderedBasicBlock::comesBefore.
|
|
BasicBlock::const_iterator LastInstFound;
|
|
|
|
/// \brief The position/number to tag the next instruction to be found.
|
|
unsigned NextInstPos;
|
|
|
|
/// \brief The source BasicBlock to map.
|
|
const BasicBlock *BB;
|
|
|
|
/// \brief Given no cached results, find if \p A comes before \p B in \p BB.
|
|
/// Cache and number out instruction while walking \p BB.
|
|
bool comesBefore(const Instruction *A, const Instruction *B);
|
|
|
|
public:
|
|
OrderedBasicBlock(const BasicBlock *BasicB);
|
|
|
|
/// \brief Find out whether \p A dominates \p B, meaning whether \p A
|
|
/// comes before \p B in \p BB. This is a simplification that considers
|
|
/// cached instruction positions and ignores other basic blocks, being
|
|
/// only relevant to compare relative instructions positions inside \p BB.
|
|
bool dominates(const Instruction *A, const Instruction *B);
|
|
};
|
|
|
|
} // End llvm namespace
|
|
|
|
#endif
|