[cfe-commits] r142885 - in /cfe/trunk: include/clang/Analysis/Analyses/Dominators.h lib/Analysis/CMakeLists.txt lib/Analysis/Dominators.cpp lib/StaticAnalyzer/Checkers/Checkers.td lib/StaticAnalyzer/Checkers/DebugCheckers.cpp test/Analysis/domtest.c
Chris Lattner
clattner at apple.com
Mon Oct 24 17:33:49 PDT 2011
On Oct 24, 2011, at 5:25 PM, Ted Kremenek wrote:
> Author: kremenek
> Date: Mon Oct 24 19:25:24 2011
> New Revision: 142885
>
> URL: http://llvm.org/viewvc/llvm-project?rev=142885&view=rev
> Log:
> Add source-level dominators analysis. Patch by Guoping Long!
This reimplements a bunch of code that we already have templates out based on Graph type (see llvm/Analysis/DominatorInternals.h). Why duplicate it? AFAICT, this is also slower than the version in llvm/Analysis.
-Chris
>
> Added:
> cfe/trunk/include/clang/Analysis/Analyses/Dominators.h
> cfe/trunk/lib/Analysis/Dominators.cpp
> cfe/trunk/test/Analysis/domtest.c
> Modified:
> cfe/trunk/lib/Analysis/CMakeLists.txt
> cfe/trunk/lib/StaticAnalyzer/Checkers/Checkers.td
> cfe/trunk/lib/StaticAnalyzer/Checkers/DebugCheckers.cpp
>
> Added: cfe/trunk/include/clang/Analysis/Analyses/Dominators.h
> URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/include/clang/Analysis/Analyses/Dominators.h?rev=142885&view=auto
> ==============================================================================
> --- cfe/trunk/include/clang/Analysis/Analyses/Dominators.h (added)
> +++ cfe/trunk/include/clang/Analysis/Analyses/Dominators.h Mon Oct 24 19:25:24 2011
> @@ -0,0 +1,156 @@
> +//==- Dominators.cpp - Construct the Dominance Tree Given CFG ----*- C++ --*-==//
> +//
> +// The LLVM Compiler Infrastructure
> +//
> +// This file is distributed under the University of Illinois Open Source
> +// License. See LICENSE.TXT for details.
> +//
> +//===----------------------------------------------------------------------===//
> +//
> +// This file implements a simple, fast dominance algorithm for source-level CFGs.
> +//
> +//===----------------------------------------------------------------------===//
> +
> +#ifndef LLVM_CLANG_DOMINATORS_H
> +#define LLVM_CLANG_DOMINATORS_H
> +
> +#include "clang/Analysis/CFG.h"
> +#include "clang/Analysis/AnalysisContext.h"
> +#include "llvm/ADT/DenseMap.h"
> +
> +namespace clang {
> +
> +class CFG;
> +class CFGBlock;
> +
> +class DominatorTree : public ManagedAnalysis {
> + typedef llvm::DenseMap<const CFGBlock *, CFGBlock*> CFGBlockMapTy;
> +
> +public:
> + DominatorTree(AnalysisDeclContext &ac)
> + : AC(ac) {};
> +
> + virtual ~DominatorTree();
> +
> + /// Return the immediate dominator node given a CFGBlock.
> + /// For entry block, the dominator is itself.
> + /// This is the same as using operator[] on this class.
> + CFGBlock *getNode(const CFGBlock *B) const;
> +
> + /// This returns the Entry Block for the given CFG
> + CFGBlock *getRootNode() { return RootNode; }
> + const CFGBlock *getRootNode() const { return RootNode; }
> +
> + /// Returns true iff A dominates B and A != B.
> + /// Note that this is not a constant time operation.
> + bool properlyDominates(const CFGBlock *A, const CFGBlock *B) const;
> +
> + /// Returns true iff A dominates B.
> + bool dominates(const CFGBlock *A, const CFGBlock *B) const;
> +
> + /// Find nearest common dominator for blocks A and B.
> + /// Common dominator always exists, ex: entry block.
> + const CFGBlock *findNearestCommonDominator(const CFGBlock *A,
> + const CFGBlock *B) const;
> +
> + /// Constructs immediate dominator tree for a given CFG based on the algorithm
> + /// described in this paper:
> + ///
> + /// A Simple, Fast Dominance Algorithm
> + /// Keith D. Cooper, Timothy J. Harvey and Ken Kennedy
> + /// Software-Practice and Expreience, 2001;4:1-10.
> + ///
> + /// This implementation is simple and runs faster in practice than the classis
> + /// Lengauer-Tarjan algorithm. For detailed discussions, refer to the paper.
> + void BuildDominatorTree();
> +
> + /// Dump the immediate dominance tree
> + void dump();
> +
> +private:
> + AnalysisDeclContext &AC;
> + CFGBlock *RootNode;
> + CFGBlockMapTy IDoms;
> +};
> +
> +} // end namespace clang
> +
> +#endif
> +//==- Dominators.cpp - Construct the Dominance Tree Given CFG ----*- C++ --*-==//
> +//
> +// The LLVM Compiler Infrastructure
> +//
> +// This file is distributed under the University of Illinois Open Source
> +// License. See LICENSE.TXT for details.
> +//
> +//===----------------------------------------------------------------------===//
> +//
> +// This file implements a simple, fast dominance algorithm for source-level CFGs.
> +//
> +//===----------------------------------------------------------------------===//
> +
> +#ifndef LLVM_CLANG_DOMINATORS_H
> +#define LLVM_CLANG_DOMINATORS_H
> +
> +#include "clang/Analysis/CFG.h"
> +#include "clang/Analysis/AnalysisDeclContext.h"
> +#include "llvm/ADT/DenseMap.h"
> +
> +namespace clang {
> +
> +class CFG;
> +class CFGBlock;
> +
> +class DominatorTree : public ManagedAnalysis {
> + typedef llvm::DenseMap<const CFGBlock *, CFGBlock*> CFGBlockMapTy;
> +
> +public:
> + DominatorTree(AnalysisDeclContext &ac)
> + : AC(ac) {};
> +
> + virtual ~DominatorTree();
> +
> + /// Return the immediate dominator node given a CFGBlock.
> + /// For entry block, the dominator is itself.
> + /// This is the same as using operator[] on this class.
> + CFGBlock *getNode(const CFGBlock *B) const;
> +
> + /// This returns the Entry Block for the given CFG
> + CFGBlock *getRootNode() { return RootNode; }
> + const CFGBlock *getRootNode() const { return RootNode; }
> +
> + /// Returns true iff A dominates B and A != B.
> + /// Note that this is not a constant time operation.
> + bool properlyDominates(const CFGBlock *A, const CFGBlock *B) const;
> +
> + /// Returns true iff A dominates B.
> + bool dominates(const CFGBlock *A, const CFGBlock *B) const;
> +
> + /// Find nearest common dominator for blocks A and B.
> + /// Common dominator always exists, ex: entry block.
> + const CFGBlock *findNearestCommonDominator(const CFGBlock *A,
> + const CFGBlock *B) const;
> +
> + /// Constructs immediate dominator tree for a given CFG based on the algorithm
> + /// described in this paper:
> + ///
> + /// A Simple, Fast Dominance Algorithm
> + /// Keith D. Cooper, Timothy J. Harvey and Ken Kennedy
> + /// Software-Practice and Expreience, 2001;4:1-10.
> + ///
> + /// This implementation is simple and runs faster in practice than the classis
> + /// Lengauer-Tarjan algorithm. For detailed discussions, refer to the paper.
> + void BuildDominatorTree();
> +
> + /// Dump the immediate dominance tree
> + void dump();
> +
> +private:
> + AnalysisDeclContext &AC;
> + CFGBlock *RootNode;
> + CFGBlockMapTy IDoms;
> +};
> +
> +} // end namespace clang
> +
> +#endif
>
> Modified: cfe/trunk/lib/Analysis/CMakeLists.txt
> URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/lib/Analysis/CMakeLists.txt?rev=142885&r1=142884&r2=142885&view=diff
> ==============================================================================
> --- cfe/trunk/lib/Analysis/CMakeLists.txt (original)
> +++ cfe/trunk/lib/Analysis/CMakeLists.txt Mon Oct 24 19:25:24 2011
> @@ -6,6 +6,7 @@
> CFGReachabilityAnalysis.cpp
> CFGStmtMap.cpp
> CocoaConventions.cpp
> + Dominators.cpp
> FormatString.cpp
> LiveVariables.cpp
> PostOrderCFGView.cpp
>
> Added: cfe/trunk/lib/Analysis/Dominators.cpp
> URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/lib/Analysis/Dominators.cpp?rev=142885&view=auto
> ==============================================================================
> --- cfe/trunk/lib/Analysis/Dominators.cpp (added)
> +++ cfe/trunk/lib/Analysis/Dominators.cpp Mon Oct 24 19:25:24 2011
> @@ -0,0 +1,160 @@
> +//==- Dominators.cpp - Construct the Dominance Tree Given CFG ----*- C++ --*-==//
> +//
> +// The LLVM Compiler Infrastructure
> +//
> +// This file is distributed under the University of Illinois Open Source
> +// License. See LICENSE.TXT for details.
> +//
> +//===----------------------------------------------------------------------===//
> +//
> +// This file implements a simple, fast dominance algorithm for source-level CFGs.
> +//
> +//===----------------------------------------------------------------------===//
> +
> +#include "clang/Analysis/Analyses/Dominators.h"
> +#include "clang/Analysis/CFG.h"
> +#include "clang/Analysis/AnalysisContext.h"
> +#include "clang/Analysis/Analyses/PostOrderCFGView.h"
> +
> +using namespace clang;
> +
> +DominatorTree::~DominatorTree() {
> + IDoms.clear();
> + RootNode = 0;
> +}
> +
> +CFGBlock * DominatorTree::getNode(const CFGBlock *B) const {
> + CFGBlockMapTy::const_iterator I = IDoms.find(B);
> + return I != IDoms.end() ? I->second : 0;
> +}
> +
> +bool DominatorTree::properlyDominates(const CFGBlock *A,
> + const CFGBlock *B) const {
> + if (0 == A || 0 == B || A == B)
> + return false;
> +
> + // The EntryBlock dominates every other block.
> + if (A == RootNode)
> + return true;
> +
> + // Note: The dominator of the EntryBlock is itself.
> + CFGBlock *IDom = getNode(B);
> + while (IDom != A && IDom != RootNode)
> + IDom = getNode(IDom);
> +
> + return IDom != RootNode;
> +}
> +
> +bool DominatorTree::dominates(const CFGBlock *A,
> + const CFGBlock *B) const {
> + if (A == B)
> + return true;
> +
> + return properlyDominates(A, B);
> +}
> +
> +const CFGBlock * DominatorTree::findNearestCommonDominator
> + (const CFGBlock *A, const CFGBlock *B) const {
> + //If A dominates B, then A is the nearest common dominator
> + if (dominates(A, B))
> + return A;
> +
> + //If B dominates A, then B is the nearest common dominator
> + if (dominates(B, A))
> + return B;
> +
> + //Collect all A's dominators
> + llvm::SmallPtrSet<CFGBlock *, 16> ADoms;
> + ADoms.insert(RootNode);
> + CFGBlock *ADom = getNode(A);
> + while (ADom != RootNode) {
> + ADoms.insert(ADom);
> + ADom = getNode(ADom);
> + }
> +
> + //Check all B's dominators against ADoms
> + CFGBlock *BDom = getNode(B);
> + while (BDom != RootNode){
> + if (ADoms.count(BDom) != 0)
> + return BDom;
> +
> + BDom = getNode(BDom);
> + }
> +
> + //The RootNode dominates every other node
> + return RootNode;
> +}
> +
> +/// Constructs immediate dominator tree for a given CFG based on the algorithm
> +/// described in this paper:
> +///
> +/// A Simple, Fast Dominance Algorithm
> +/// Keith D. Cooper, Timothy J. Harvey and Ken Kennedy
> +/// Software-Practice and Expreience, 2001;4:1-10.
> +///
> +/// This implementation is simple and runs faster in practice than the classis
> +/// Lengauer-Tarjan algorithm. For detailed discussions, refer to the paper.
> +void DominatorTree::BuildDominatorTree() {
> + CFG *cfg = AC.getCFG();
> + CFGBlock *EntryBlk = &cfg->getEntry();
> +
> + //Sort all CFGBlocks in reverse order
> + PostOrderCFGView *rpocfg = AC.getAnalysis<PostOrderCFGView>();
> +
> + //Set the root of the dominance tree
> + RootNode = EntryBlk;
> +
> + //Compute the immediate dominator for each CFGBlock
> + IDoms[EntryBlk] = EntryBlk;
> + bool changed = true;
> + while (changed){
> + changed = false;
> +
> + for (PostOrderCFGView::iterator I = rpocfg->begin(),
> + E = rpocfg->end(); I != E; ++I){
> + if (EntryBlk == *I)
> + continue;
> + if (const CFGBlock *B = *I) {
> + //Compute immediate dominance information for CFGBlock B
> + CFGBlock *IDom = 0;
> + for (CFGBlock::const_pred_iterator J = B->pred_begin(),
> + K = B->pred_end(); J != K; ++J)
> + if( CFGBlock *P = *J) {
> + if (IDoms.find(P) == IDoms.end())
> + continue;
> + if (!IDom)
> + IDom = P;
> + else {
> + //intersect IDom and P
> + CFGBlock *B1 = IDom, *B2 = P;
> + while (B1 != B2) {
> + while ((rpocfg->getComparator())(B2,B1))
> + B1 = IDoms[B1];
> + while ((rpocfg->getComparator())(B1,B2))
> + B2 = IDoms[B2];
> + }
> + IDom = B1;
> + }
> + }
> + if (IDoms[B] != IDom) {
> + IDoms[B] = IDom;
> + changed = true;
> + }
> + }
> + }
> + }//while
> +}
> +
> +void DominatorTree::dump() {
> + CFG *cfg = AC.getCFG();
> +
> + llvm::errs() << "Immediate dominance tree (Node#,IDom#):\n";
> + for (CFG::const_iterator I = cfg->begin(),
> + E = cfg->end(); I != E; ++I) {
> + assert(IDoms[(*I)] &&
> + "Failed to find the immediate dominator for all CFG blocks.");
> + llvm::errs() << "(" << (*I)->getBlockID()
> + << "," << IDoms[(*I)]->getBlockID() << ")\n";
> + }
> +}
> +
>
> Modified: cfe/trunk/lib/StaticAnalyzer/Checkers/Checkers.td
> URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/lib/StaticAnalyzer/Checkers/Checkers.td?rev=142885&r1=142884&r2=142885&view=diff
> ==============================================================================
> --- cfe/trunk/lib/StaticAnalyzer/Checkers/Checkers.td (original)
> +++ cfe/trunk/lib/StaticAnalyzer/Checkers/Checkers.td Mon Oct 24 19:25:24 2011
> @@ -359,6 +359,10 @@
>
> let ParentPackage = Debug in {
>
> +def DominatorsTreeDumper : Checker<"DumpDominators">,
> + HelpText<"Print the dominance tree for a given CFG">,
> + DescFile<"DebugCheckers.cpp">;
> +
> def LiveVariablesDumper : Checker<"DumpLiveVars">,
> HelpText<"Print results of live variable analysis">,
> DescFile<"DebugCheckers.cpp">;
>
> Modified: cfe/trunk/lib/StaticAnalyzer/Checkers/DebugCheckers.cpp
> URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/lib/StaticAnalyzer/Checkers/DebugCheckers.cpp?rev=142885&r1=142884&r2=142885&view=diff
> ==============================================================================
> --- cfe/trunk/lib/StaticAnalyzer/Checkers/DebugCheckers.cpp (original)
> +++ cfe/trunk/lib/StaticAnalyzer/Checkers/DebugCheckers.cpp Mon Oct 24 19:25:24 2011
> @@ -15,11 +15,34 @@
> #include "clang/StaticAnalyzer/Core/Checker.h"
> #include "clang/StaticAnalyzer/Core/PathSensitive/AnalysisManager.h"
> #include "clang/Analysis/Analyses/LiveVariables.h"
> +#include "clang/Analysis/Analyses/Dominators.h"
>
> using namespace clang;
> using namespace ento;
>
> //===----------------------------------------------------------------------===//
> +// DominatorsTreeDumper
> +//===----------------------------------------------------------------------===//
> +
> +namespace {
> +class DominatorsTreeDumper : public Checker<check::ASTCodeBody> {
> +public:
> + void checkASTCodeBody(const Decl *D, AnalysisManager& mgr,
> + BugReporter &BR) const {
> + if (AnalysisDeclContext *AC = mgr.getAnalysisDeclContext(D)) {
> + DominatorTree dom(*AC);
> + dom.BuildDominatorTree();
> + dom.dump();
> + }
> + }
> +};
> +}
> +
> +void ento::registerDominatorsTreeDumper(CheckerManager &mgr) {
> + mgr.registerChecker<DominatorsTreeDumper>();
> +}
> +
> +//===----------------------------------------------------------------------===//
> // LiveVariablesDumper
> //===----------------------------------------------------------------------===//
>
>
> Added: cfe/trunk/test/Analysis/domtest.c
> URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/test/Analysis/domtest.c?rev=142885&view=auto
> ==============================================================================
> --- cfe/trunk/test/Analysis/domtest.c (added)
> +++ cfe/trunk/test/Analysis/domtest.c Mon Oct 24 19:25:24 2011
> @@ -0,0 +1,165 @@
> +// RUN: %clang -cc1 -analyze -analyzer-checker=debug.DumpDominators %s 2>&1 | FileCheck %s
> +
> +// Test the DominatorsTree implementation with various control flows
> +int test1()
> +{
> + int x = 6;
> + int y = x/2;
> + int z;
> +
> + while(y > 0) {
> + if(y < x) {
> + x = x/y;
> + y = y-1;
> + }else{
> + z = x - y;
> + }
> + x = x - 1;
> + x = x - 1;
> + }
> + z = x+y;
> + z = 3;
> + return 0;
> +}
> +
> +// CHECK: Immediate dominance tree (Node#,IDom#):
> +// CHECK: (0,1)
> +// CHECK: (1,2)
> +// CHECK: (2,8)
> +// CHECK: (3,4)
> +// CHECK: (4,7)
> +// CHECK: (5,7)
> +// CHECK: (6,7)
> +// CHECK: (7,2)
> +// CHECK: (8,9)
> +// CHECK: (9,9)
> +
> +int test2()
> +{
> + int x,y,z;
> +
> + x = 10; y = 100;
> + if(x > 0){
> + y = 1;
> + }else{
> + while(x<=0){
> + x++;
> + y++;
> + }
> + }
> + z = y;
> +
> + return 0;
> +}
> +
> +// CHECK: Immediate dominance tree (Node#,IDom#):
> +// CHECK: (0,1)
> +// CHECK: (1,6)
> +// CHECK: (2,6)
> +// CHECK: (3,4)
> +// CHECK: (4,2)
> +// CHECK: (5,6)
> +// CHECK: (6,7)
> +// CHECK: (7,7)
> +
> +int test3()
> +{
> + int x,y,z;
> +
> + x = y = z = 1;
> + if(x>0) {
> + while(x>=0){
> + while(y>=x) {
> + x = x-1;
> + y = y/2;
> + }
> + }
> + }
> + z = y;
> +
> + return 0;
> +}
> +
> +// CHECK: Immediate dominance tree (Node#,IDom#):
> +// CHECK: (0,1)
> +// CHECK: (1,7)
> +// CHECK: (2,7)
> +// CHECK: (3,4)
> +// CHECK: (4,2)
> +// CHECK: (5,6)
> +// CHECK: (6,4)
> +// CHECK: (7,8)
> +// CHECK: (8,8)
> +
> +int test4()
> +{
> + int y = 3;
> + while(y > 0) {
> + if(y < 3) {
> + while(y>0)
> + y ++;
> + }else{
> + while(y<10)
> + y ++;
> + }
> + }
> + return 0;
> +}
> +
> +// CHECK: Immediate dominance tree (Node#,IDom#):
> +// CHECK: (0,1)
> +// CHECK: (1,2)
> +// CHECK: (2,11)
> +// CHECK: (3,10)
> +// CHECK: (4,10)
> +// CHECK: (5,6)
> +// CHECK: (6,4)
> +// CHECK: (7,10)
> +// CHECK: (8,9)
> +// CHECK: (9,7)
> +// CHECK: (10,2)
> +// CHECK: (11,12)
> +// CHECK: (12,12)
> +
> +int test5()
> +{
> + int x,y,z,a,b,c;
> + x = 1;
> + y = 2;
> + z = 3;
> + a = 4;
> + b = 5;
> + c = 6;
> + if ( x < 10 ) {
> + if ( y < 10 ) {
> + if ( z < 10 ) {
> + x = 4;
> + } else {
> + x = 5;
> + }
> + a = 10;
> + } else {
> + x = 6;
> + }
> + b = 10;
> + } else {
> + x = 7;
> + }
> + c = 11;
> + return 0;
> +}
> +
> +// CHECK: Immediate dominance tree (Node#,IDom#):
> +// CHECK: (0,1)
> +// CHECK: (1,10)
> +// CHECK: (2,10)
> +// CHECK: (3,9)
> +// CHECK: (4,9)
> +// CHECK: (5,8)
> +// CHECK: (6,8)
> +// CHECK: (7,8)
> +// CHECK: (8,9)
> +// CHECK: (9,10)
> +// CHECK: (10,11)
> +// CHECK: (11,11)
> +
>
>
> _______________________________________________
> cfe-commits mailing list
> cfe-commits at cs.uiuc.edu
> http://lists.cs.uiuc.edu/mailman/listinfo/cfe-commits
More information about the cfe-commits
mailing list