1894018228b0e0bdbd7aa7e8f47d4a9458789ca82John Bauman//===- llvm/Analysis/Trace.h - Represent one trace of LLVM code -*- C++ -*-===// 2894018228b0e0bdbd7aa7e8f47d4a9458789ca82John Bauman// 3894018228b0e0bdbd7aa7e8f47d4a9458789ca82John Bauman// The LLVM Compiler Infrastructure 4894018228b0e0bdbd7aa7e8f47d4a9458789ca82John Bauman// 5894018228b0e0bdbd7aa7e8f47d4a9458789ca82John Bauman// This file is distributed under the University of Illinois Open Source 6894018228b0e0bdbd7aa7e8f47d4a9458789ca82John Bauman// License. See LICENSE.TXT for details. 7894018228b0e0bdbd7aa7e8f47d4a9458789ca82John Bauman// 8894018228b0e0bdbd7aa7e8f47d4a9458789ca82John Bauman//===----------------------------------------------------------------------===// 9894018228b0e0bdbd7aa7e8f47d4a9458789ca82John Bauman// 10894018228b0e0bdbd7aa7e8f47d4a9458789ca82John Bauman// This class represents a single trace of LLVM basic blocks. A trace is a 11894018228b0e0bdbd7aa7e8f47d4a9458789ca82John Bauman// single entry, multiple exit, region of code that is often hot. Trace-based 12894018228b0e0bdbd7aa7e8f47d4a9458789ca82John Bauman// optimizations treat traces almost like they are a large, strange, basic 13894018228b0e0bdbd7aa7e8f47d4a9458789ca82John Bauman// block: because the trace path is assumed to be hot, optimizations for the 14894018228b0e0bdbd7aa7e8f47d4a9458789ca82John Bauman// fall-through path are made at the expense of the non-fall-through paths. 15894018228b0e0bdbd7aa7e8f47d4a9458789ca82John Bauman// 16894018228b0e0bdbd7aa7e8f47d4a9458789ca82John Bauman//===----------------------------------------------------------------------===// 17894018228b0e0bdbd7aa7e8f47d4a9458789ca82John Bauman 18894018228b0e0bdbd7aa7e8f47d4a9458789ca82John Bauman#ifndef LLVM_ANALYSIS_TRACE_H 19894018228b0e0bdbd7aa7e8f47d4a9458789ca82John Bauman#define LLVM_ANALYSIS_TRACE_H 20894018228b0e0bdbd7aa7e8f47d4a9458789ca82John Bauman 21894018228b0e0bdbd7aa7e8f47d4a9458789ca82John Bauman#include <vector> 22894018228b0e0bdbd7aa7e8f47d4a9458789ca82John Bauman#include <cassert> 23894018228b0e0bdbd7aa7e8f47d4a9458789ca82John Bauman 24894018228b0e0bdbd7aa7e8f47d4a9458789ca82John Baumannamespace llvm { 25894018228b0e0bdbd7aa7e8f47d4a9458789ca82John Bauman class BasicBlock; 26894018228b0e0bdbd7aa7e8f47d4a9458789ca82John Bauman class Function; 27894018228b0e0bdbd7aa7e8f47d4a9458789ca82John Bauman class Module; 28894018228b0e0bdbd7aa7e8f47d4a9458789ca82John Bauman class raw_ostream; 29894018228b0e0bdbd7aa7e8f47d4a9458789ca82John Bauman 30894018228b0e0bdbd7aa7e8f47d4a9458789ca82John Baumanclass Trace { 31894018228b0e0bdbd7aa7e8f47d4a9458789ca82John Bauman typedef std::vector<BasicBlock *> BasicBlockListType; 32894018228b0e0bdbd7aa7e8f47d4a9458789ca82John Bauman BasicBlockListType BasicBlocks; 33894018228b0e0bdbd7aa7e8f47d4a9458789ca82John Bauman 34894018228b0e0bdbd7aa7e8f47d4a9458789ca82John Baumanpublic: 35894018228b0e0bdbd7aa7e8f47d4a9458789ca82John Bauman /// Trace ctor - Make a new trace from a vector of basic blocks, 36894018228b0e0bdbd7aa7e8f47d4a9458789ca82John Bauman /// residing in the function which is the parent of the first 37894018228b0e0bdbd7aa7e8f47d4a9458789ca82John Bauman /// basic block in the vector. 38894018228b0e0bdbd7aa7e8f47d4a9458789ca82John Bauman /// 39894018228b0e0bdbd7aa7e8f47d4a9458789ca82John Bauman Trace(const std::vector<BasicBlock *> &vBB) : BasicBlocks (vBB) {} 40894018228b0e0bdbd7aa7e8f47d4a9458789ca82John Bauman 41894018228b0e0bdbd7aa7e8f47d4a9458789ca82John Bauman /// getEntryBasicBlock - Return the entry basic block (first block) 42894018228b0e0bdbd7aa7e8f47d4a9458789ca82John Bauman /// of the trace. 43894018228b0e0bdbd7aa7e8f47d4a9458789ca82John Bauman /// 44894018228b0e0bdbd7aa7e8f47d4a9458789ca82John Bauman BasicBlock *getEntryBasicBlock () const { return BasicBlocks[0]; } 45894018228b0e0bdbd7aa7e8f47d4a9458789ca82John Bauman 46894018228b0e0bdbd7aa7e8f47d4a9458789ca82John Bauman /// operator[]/getBlock - Return basic block N in the trace. 47894018228b0e0bdbd7aa7e8f47d4a9458789ca82John Bauman /// 48894018228b0e0bdbd7aa7e8f47d4a9458789ca82John Bauman BasicBlock *operator[](unsigned i) const { return BasicBlocks[i]; } 49894018228b0e0bdbd7aa7e8f47d4a9458789ca82John Bauman BasicBlock *getBlock(unsigned i) const { return BasicBlocks[i]; } 50894018228b0e0bdbd7aa7e8f47d4a9458789ca82John Bauman 51894018228b0e0bdbd7aa7e8f47d4a9458789ca82John Bauman /// getFunction - Return this trace's parent function. 52894018228b0e0bdbd7aa7e8f47d4a9458789ca82John Bauman /// 53894018228b0e0bdbd7aa7e8f47d4a9458789ca82John Bauman Function *getFunction () const; 54894018228b0e0bdbd7aa7e8f47d4a9458789ca82John Bauman 55894018228b0e0bdbd7aa7e8f47d4a9458789ca82John Bauman /// getModule - Return this Module that contains this trace's parent 56894018228b0e0bdbd7aa7e8f47d4a9458789ca82John Bauman /// function. 57894018228b0e0bdbd7aa7e8f47d4a9458789ca82John Bauman /// 58894018228b0e0bdbd7aa7e8f47d4a9458789ca82John Bauman Module *getModule () const; 59894018228b0e0bdbd7aa7e8f47d4a9458789ca82John Bauman 60894018228b0e0bdbd7aa7e8f47d4a9458789ca82John Bauman /// getBlockIndex - Return the index of the specified basic block in the 61894018228b0e0bdbd7aa7e8f47d4a9458789ca82John Bauman /// trace, or -1 if it is not in the trace. 62894018228b0e0bdbd7aa7e8f47d4a9458789ca82John Bauman int getBlockIndex(const BasicBlock *X) const { 63894018228b0e0bdbd7aa7e8f47d4a9458789ca82John Bauman for (unsigned i = 0, e = BasicBlocks.size(); i != e; ++i) 64894018228b0e0bdbd7aa7e8f47d4a9458789ca82John Bauman if (BasicBlocks[i] == X) 65894018228b0e0bdbd7aa7e8f47d4a9458789ca82John Bauman return i; 66894018228b0e0bdbd7aa7e8f47d4a9458789ca82John Bauman return -1; 67894018228b0e0bdbd7aa7e8f47d4a9458789ca82John Bauman } 68894018228b0e0bdbd7aa7e8f47d4a9458789ca82John Bauman 69894018228b0e0bdbd7aa7e8f47d4a9458789ca82John Bauman /// contains - Returns true if this trace contains the given basic 70894018228b0e0bdbd7aa7e8f47d4a9458789ca82John Bauman /// block. 71894018228b0e0bdbd7aa7e8f47d4a9458789ca82John Bauman /// 72894018228b0e0bdbd7aa7e8f47d4a9458789ca82John Bauman bool contains(const BasicBlock *X) const { 73894018228b0e0bdbd7aa7e8f47d4a9458789ca82John Bauman return getBlockIndex(X) != -1; 74894018228b0e0bdbd7aa7e8f47d4a9458789ca82John Bauman } 75894018228b0e0bdbd7aa7e8f47d4a9458789ca82John Bauman 76894018228b0e0bdbd7aa7e8f47d4a9458789ca82John Bauman /// Returns true if B1 occurs before B2 in the trace, or if it is the same 77894018228b0e0bdbd7aa7e8f47d4a9458789ca82John Bauman /// block as B2.. Both blocks must be in the trace. 78894018228b0e0bdbd7aa7e8f47d4a9458789ca82John Bauman /// 79894018228b0e0bdbd7aa7e8f47d4a9458789ca82John Bauman bool dominates(const BasicBlock *B1, const BasicBlock *B2) const { 80894018228b0e0bdbd7aa7e8f47d4a9458789ca82John Bauman int B1Idx = getBlockIndex(B1), B2Idx = getBlockIndex(B2); 81894018228b0e0bdbd7aa7e8f47d4a9458789ca82John Bauman assert(B1Idx != -1 && B2Idx != -1 && "Block is not in the trace!"); 82894018228b0e0bdbd7aa7e8f47d4a9458789ca82John Bauman return B1Idx <= B2Idx; 83894018228b0e0bdbd7aa7e8f47d4a9458789ca82John Bauman } 84894018228b0e0bdbd7aa7e8f47d4a9458789ca82John Bauman 85894018228b0e0bdbd7aa7e8f47d4a9458789ca82John Bauman // BasicBlock iterators... 86894018228b0e0bdbd7aa7e8f47d4a9458789ca82John Bauman typedef BasicBlockListType::iterator iterator; 87894018228b0e0bdbd7aa7e8f47d4a9458789ca82John Bauman typedef BasicBlockListType::const_iterator const_iterator; 88894018228b0e0bdbd7aa7e8f47d4a9458789ca82John Bauman typedef std::reverse_iterator<const_iterator> const_reverse_iterator; 89894018228b0e0bdbd7aa7e8f47d4a9458789ca82John Bauman typedef std::reverse_iterator<iterator> reverse_iterator; 90894018228b0e0bdbd7aa7e8f47d4a9458789ca82John Bauman 91894018228b0e0bdbd7aa7e8f47d4a9458789ca82John Bauman iterator begin() { return BasicBlocks.begin(); } 92894018228b0e0bdbd7aa7e8f47d4a9458789ca82John Bauman const_iterator begin() const { return BasicBlocks.begin(); } 93894018228b0e0bdbd7aa7e8f47d4a9458789ca82John Bauman iterator end () { return BasicBlocks.end(); } 94894018228b0e0bdbd7aa7e8f47d4a9458789ca82John Bauman const_iterator end () const { return BasicBlocks.end(); } 95894018228b0e0bdbd7aa7e8f47d4a9458789ca82John Bauman 96894018228b0e0bdbd7aa7e8f47d4a9458789ca82John Bauman reverse_iterator rbegin() { return BasicBlocks.rbegin(); } 97894018228b0e0bdbd7aa7e8f47d4a9458789ca82John Bauman const_reverse_iterator rbegin() const { return BasicBlocks.rbegin(); } 98894018228b0e0bdbd7aa7e8f47d4a9458789ca82John Bauman reverse_iterator rend () { return BasicBlocks.rend(); } 99894018228b0e0bdbd7aa7e8f47d4a9458789ca82John Bauman const_reverse_iterator rend () const { return BasicBlocks.rend(); } 100894018228b0e0bdbd7aa7e8f47d4a9458789ca82John Bauman 101894018228b0e0bdbd7aa7e8f47d4a9458789ca82John Bauman unsigned size() const { return BasicBlocks.size(); } 102894018228b0e0bdbd7aa7e8f47d4a9458789ca82John Bauman bool empty() const { return BasicBlocks.empty(); } 103894018228b0e0bdbd7aa7e8f47d4a9458789ca82John Bauman 104894018228b0e0bdbd7aa7e8f47d4a9458789ca82John Bauman iterator erase(iterator q) { return BasicBlocks.erase (q); } 105894018228b0e0bdbd7aa7e8f47d4a9458789ca82John Bauman iterator erase(iterator q1, iterator q2) { return BasicBlocks.erase (q1, q2); } 106894018228b0e0bdbd7aa7e8f47d4a9458789ca82John Bauman 107894018228b0e0bdbd7aa7e8f47d4a9458789ca82John Bauman /// print - Write trace to output stream. 108894018228b0e0bdbd7aa7e8f47d4a9458789ca82John Bauman /// 109894018228b0e0bdbd7aa7e8f47d4a9458789ca82John Bauman void print(raw_ostream &O) const; 110894018228b0e0bdbd7aa7e8f47d4a9458789ca82John Bauman 111894018228b0e0bdbd7aa7e8f47d4a9458789ca82John Bauman /// dump - Debugger convenience method; writes trace to standard error 112894018228b0e0bdbd7aa7e8f47d4a9458789ca82John Bauman /// output stream. 113894018228b0e0bdbd7aa7e8f47d4a9458789ca82John Bauman /// 114894018228b0e0bdbd7aa7e8f47d4a9458789ca82John Bauman void dump() const; 115894018228b0e0bdbd7aa7e8f47d4a9458789ca82John Bauman}; 116894018228b0e0bdbd7aa7e8f47d4a9458789ca82John Bauman 117894018228b0e0bdbd7aa7e8f47d4a9458789ca82John Bauman} // end namespace llvm 118894018228b0e0bdbd7aa7e8f47d4a9458789ca82John Bauman 119894018228b0e0bdbd7aa7e8f47d4a9458789ca82John Bauman#endif // TRACE_H 120