Coverage Report

Created: 2019-02-20 00:17

/Users/buildslave/jenkins/workspace/clang-stage2-coverage-R/llvm/include/llvm/CodeGen/LexicalScopes.h
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//===- LexicalScopes.cpp - Collecting lexical scope info --------*- C++ -*-===//
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//
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// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
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// See https://llvm.org/LICENSE.txt for license information.
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// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
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//
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//===----------------------------------------------------------------------===//
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//
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// This file implements LexicalScopes analysis.
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//
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// This pass collects lexical scope information and maps machine instructions
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// to respective lexical scopes.
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//
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//===----------------------------------------------------------------------===//
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#ifndef LLVM_CODEGEN_LEXICALSCOPES_H
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#define LLVM_CODEGEN_LEXICALSCOPES_H
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#include "llvm/ADT/ArrayRef.h"
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#include "llvm/ADT/DenseMap.h"
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#include "llvm/ADT/SmallPtrSet.h"
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#include "llvm/ADT/SmallVector.h"
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#include "llvm/IR/DebugInfoMetadata.h"
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#include <cassert>
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#include <unordered_map>
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#include <utility>
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namespace llvm {
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class MachineBasicBlock;
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class MachineFunction;
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class MachineInstr;
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class MDNode;
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//===----------------------------------------------------------------------===//
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/// InsnRange - This is used to track range of instructions with identical
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/// lexical scope.
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///
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using InsnRange = std::pair<const MachineInstr *, const MachineInstr *>;
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//===----------------------------------------------------------------------===//
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/// LexicalScope - This class is used to track scope information.
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///
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class LexicalScope {
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public:
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  LexicalScope(LexicalScope *P, const DILocalScope *D, const DILocation *I,
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               bool A)
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1.54M
      : Parent(P), Desc(D), InlinedAtLocation(I), AbstractScope(A) {
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1.54M
    assert(D);
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1.54M
    assert(D->getSubprogram()->getUnit()->getEmissionKind() !=
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1.54M
           DICompileUnit::NoDebug &&
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1.54M
           "Don't build lexical scopes for non-debug locations");
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    assert(D->isResolved() && "Expected resolved node");
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1.54M
    assert((!I || I->isResolved()) && "Expected resolved node");
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1.54M
    if (Parent)
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930k
      Parent->addChild(this);
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  }
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  // Accessors.
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  LexicalScope *getParent() const { return Parent; }
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  const MDNode *getDesc() const { return Desc; }
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  const DILocation *getInlinedAt() const { return InlinedAtLocation; }
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  const DILocalScope *getScopeNode() const { return Desc; }
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  bool isAbstractScope() const { return AbstractScope; }
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2.70M
  SmallVectorImpl<LexicalScope *> &getChildren() { return Children; }
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  SmallVectorImpl<InsnRange> &getRanges() { return Ranges; }
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  /// addChild - Add a child scope.
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  void addChild(LexicalScope *S) { Children.push_back(S); }
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  /// openInsnRange - This scope covers instruction range starting from MI.
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7.32M
  void openInsnRange(const MachineInstr *MI) {
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    if (!FirstInsn)
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1.24M
      FirstInsn = MI;
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7.32M
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    if (Parent)
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      Parent->openInsnRange(MI);
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  }
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  /// extendInsnRange - Extend the current instruction range covered by
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  /// this scope.
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  void extendInsnRange(const MachineInstr *MI) {
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    assert(FirstInsn && "MI Range is not open!");
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    LastInsn = MI;
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    if (Parent)
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      Parent->extendInsnRange(MI);
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  }
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  /// closeInsnRange - Create a range based on FirstInsn and LastInsn collected
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  /// until now. This is used when a new scope is encountered while walking
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  /// machine instructions.
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  void closeInsnRange(LexicalScope *NewScope = nullptr) {
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    assert(LastInsn && "Last insn missing!");
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    Ranges.push_back(InsnRange(FirstInsn, LastInsn));
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    FirstInsn = nullptr;
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    LastInsn = nullptr;
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    // If Parent dominates NewScope then do not close Parent's instruction
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    // range.
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    if (Parent && 
(1.14M
!NewScope1.14M
||
!Parent->dominates(NewScope)1.11M
))
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      Parent->closeInsnRange(NewScope);
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  }
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  /// dominates - Return true if current scope dominates given lexical scope.
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  bool dominates(const LexicalScope *S) const {
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    if (S == this)
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      return true;
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    if (DFSIn < S->getDFSIn() && 
DFSOut > S->getDFSOut()896k
)
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      return true;
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    return false;
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  }
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  // Depth First Search support to walk and manipulate LexicalScope hierarchy.
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  unsigned getDFSOut() const { return DFSOut; }
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  void setDFSOut(unsigned O) { DFSOut = O; }
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  unsigned getDFSIn() const { return DFSIn; }
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  void setDFSIn(unsigned I) { DFSIn = I; }
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  /// dump - print lexical scope.
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  void dump(unsigned Indent = 0) const;
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private:
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  LexicalScope *Parent;                        // Parent to this scope.
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  const DILocalScope *Desc;                    // Debug info descriptor.
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  const DILocation *InlinedAtLocation;         // Location at which this
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                                               // scope is inlined.
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  bool AbstractScope;                          // Abstract Scope
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  SmallVector<LexicalScope *, 4> Children;     // Scopes defined in scope.
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                                               // Contents not owned.
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  SmallVector<InsnRange, 4> Ranges;
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  const MachineInstr *LastInsn = nullptr;  // Last instruction of this scope.
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  const MachineInstr *FirstInsn = nullptr; // First instruction of this scope.
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  unsigned DFSIn = 0; // In & Out Depth use to determine scope nesting.
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  unsigned DFSOut = 0;
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};
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//===----------------------------------------------------------------------===//
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/// LexicalScopes -  This class provides interface to collect and use lexical
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/// scoping information from machine instruction.
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///
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class LexicalScopes {
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public:
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  LexicalScopes() = default;
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  /// initialize - Scan machine function and constuct lexical scope nest, resets
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  /// the instance if necessary.
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  void initialize(const MachineFunction &);
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  /// releaseMemory - release memory.
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  void reset();
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  /// empty - Return true if there is any lexical scope information available.
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  bool empty() { return CurrentFnLexicalScope == nullptr; }
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  /// getCurrentFunctionScope - Return lexical scope for the current function.
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  LexicalScope *getCurrentFunctionScope() const {
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    return CurrentFnLexicalScope;
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  }
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  /// getMachineBasicBlocks - Populate given set using machine basic blocks
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  /// which have machine instructions that belong to lexical scope identified by
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  /// DebugLoc.
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  void getMachineBasicBlocks(const DILocation *DL,
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                             SmallPtrSetImpl<const MachineBasicBlock *> &MBBs);
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  /// dominates - Return true if DebugLoc's lexical scope dominates at least one
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  /// machine instruction's lexical scope in a given machine basic block.
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  bool dominates(const DILocation *DL, MachineBasicBlock *MBB);
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  /// findLexicalScope - Find lexical scope, either regular or inlined, for the
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  /// given DebugLoc. Return NULL if not found.
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  LexicalScope *findLexicalScope(const DILocation *DL);
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  /// getAbstractScopesList - Return a reference to list of abstract scopes.
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  ArrayRef<LexicalScope *> getAbstractScopesList() const {
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    return AbstractScopesList;
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  }
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  /// findAbstractScope - Find an abstract scope or return null.
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  LexicalScope *findAbstractScope(const DILocalScope *N) {
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    auto I = AbstractScopeMap.find(N);
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    return I != AbstractScopeMap.end() ? 
&I->second88
:
nullptr1.00k
;
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  }
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  /// findInlinedScope - Find an inlined scope for the given scope/inlined-at.
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  LexicalScope *findInlinedScope(const DILocalScope *N, const DILocation *IA) {
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    auto I = InlinedLexicalScopeMap.find(std::make_pair(N, IA));
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    return I != InlinedLexicalScopeMap.end() ? 
&I->second73
:
nullptr6
;
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  }
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  /// findLexicalScope - Find regular lexical scope or return null.
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  LexicalScope *findLexicalScope(const DILocalScope *N) {
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    auto I = LexicalScopeMap.find(N);
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    return I != LexicalScopeMap.end() ? 
&I->second2.16k
:
nullptr49
;
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  }
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  /// dump - Print data structures to dbgs().
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  void dump() const;
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  /// getOrCreateAbstractScope - Find or create an abstract lexical scope.
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  LexicalScope *getOrCreateAbstractScope(const DILocalScope *Scope);
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private:
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  /// getOrCreateLexicalScope - Find lexical scope for the given Scope/IA. If
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  /// not available then create new lexical scope.
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  LexicalScope *getOrCreateLexicalScope(const DILocalScope *Scope,
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                                        const DILocation *IA = nullptr);
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3.90M
  LexicalScope *getOrCreateLexicalScope(const DILocation *DL) {
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    return DL ? getOrCreateLexicalScope(DL->getScope(), DL->getInlinedAt())
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              : 
nullptr0
;
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  }
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  /// getOrCreateRegularScope - Find or create a regular lexical scope.
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  LexicalScope *getOrCreateRegularScope(const DILocalScope *Scope);
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  /// getOrCreateInlinedScope - Find or create an inlined lexical scope.
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  LexicalScope *getOrCreateInlinedScope(const DILocalScope *Scope,
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                                        const DILocation *InlinedAt);
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  /// extractLexicalScopes - Extract instruction ranges for each lexical scopes
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  /// for the given machine function.
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  void extractLexicalScopes(SmallVectorImpl<InsnRange> &MIRanges,
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                            DenseMap<const MachineInstr *, LexicalScope *> &M);
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  void constructScopeNest(LexicalScope *Scope);
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  void
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  assignInstructionRanges(SmallVectorImpl<InsnRange> &MIRanges,
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                          DenseMap<const MachineInstr *, LexicalScope *> &M);
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  const MachineFunction *MF = nullptr;
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  /// LexicalScopeMap - Tracks the scopes in the current function.
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  // Use an unordered_map to ensure value pointer validity over insertion.
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  std::unordered_map<const DILocalScope *, LexicalScope> LexicalScopeMap;
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  /// InlinedLexicalScopeMap - Tracks inlined function scopes in current
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  /// function.
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  std::unordered_map<std::pair<const DILocalScope *, const DILocation *>,
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                     LexicalScope,
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                     pair_hash<const DILocalScope *, const DILocation *>>
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      InlinedLexicalScopeMap;
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  /// AbstractScopeMap - These scopes are  not included LexicalScopeMap.
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  // Use an unordered_map to ensure value pointer validity over insertion.
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  std::unordered_map<const DILocalScope *, LexicalScope> AbstractScopeMap;
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  /// AbstractScopesList - Tracks abstract scopes constructed while processing
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  /// a function.
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  SmallVector<LexicalScope *, 4> AbstractScopesList;
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  /// CurrentFnLexicalScope - Top level scope for the current function.
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  ///
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  LexicalScope *CurrentFnLexicalScope = nullptr;
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};
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} // end namespace llvm
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#endif // LLVM_CODEGEN_LEXICALSCOPES_H