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authorTed Kremenek <kremenek@apple.com>2010-01-25 04:41:41 +0000
committerTed Kremenek <kremenek@apple.com>2010-01-25 04:41:41 +0000
commit1309f9a3b225ea846e5822691c39a77423125505 (patch)
tree1ba6d1976da4f426292619af026dbf9d9314c573 /lib/Analysis/BasicConstraintManager.cpp
parent3db9eb1fbe5771d3d64db01af46b4eee9aca8ed0 (diff)
Split libAnalysis into two libraries: libAnalysis and libChecker.
(1) libAnalysis is a generic analysis library that can be used by Sema. It defines the CFG, basic dataflow analysis primitives, and inexpensive flow-sensitive analyses (e.g. LiveVariables). (2) libChecker contains the guts of the static analyzer, incuding the path-sensitive analysis engine and domain-specific checks. Now any clients that want to use the frontend to build their own tools don't need to link in the entire static analyzer. This change exposes various obvious cleanups that can be made to the layout of files and headers in libChecker. More changes pending. :) This change also exposed a layering violation between AnalysisContext and MemRegion. BlockInvocationContext shouldn't explicitly know about BlockDataRegions. For now I've removed the BlockDataRegion* from BlockInvocationContext (removing context-sensitivity; although this wasn't used yet). We need to have a better way to extend BlockInvocationContext (and any LocationContext) to add context-sensitivty. git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@94406 91177308-0d34-0410-b5e6-96231b3b80d8
Diffstat (limited to 'lib/Analysis/BasicConstraintManager.cpp')
-rw-r--r--lib/Analysis/BasicConstraintManager.cpp317
1 files changed, 0 insertions, 317 deletions
diff --git a/lib/Analysis/BasicConstraintManager.cpp b/lib/Analysis/BasicConstraintManager.cpp
deleted file mode 100644
index 6dfc470530..0000000000
--- a/lib/Analysis/BasicConstraintManager.cpp
+++ /dev/null
@@ -1,317 +0,0 @@
-//== BasicConstraintManager.cpp - Manage basic constraints.------*- 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 BasicConstraintManager, a class that tracks simple
-// equality and inequality constraints on symbolic values of GRState.
-//
-//===----------------------------------------------------------------------===//
-
-#include "SimpleConstraintManager.h"
-#include "clang/Analysis/PathSensitive/GRState.h"
-#include "clang/Analysis/PathSensitive/GRStateTrait.h"
-#include "clang/Analysis/PathSensitive/GRTransferFuncs.h"
-#include "llvm/Support/raw_ostream.h"
-
-using namespace clang;
-
-
-namespace { class ConstNotEq {}; }
-namespace { class ConstEq {}; }
-
-typedef llvm::ImmutableMap<SymbolRef,GRState::IntSetTy> ConstNotEqTy;
-typedef llvm::ImmutableMap<SymbolRef,const llvm::APSInt*> ConstEqTy;
-
-static int ConstEqIndex = 0;
-static int ConstNotEqIndex = 0;
-
-namespace clang {
-template<>
-struct GRStateTrait<ConstNotEq> : public GRStatePartialTrait<ConstNotEqTy> {
- static inline void* GDMIndex() { return &ConstNotEqIndex; }
-};
-
-template<>
-struct GRStateTrait<ConstEq> : public GRStatePartialTrait<ConstEqTy> {
- static inline void* GDMIndex() { return &ConstEqIndex; }
-};
-}
-
-namespace {
-// BasicConstraintManager only tracks equality and inequality constraints of
-// constants and integer variables.
-class BasicConstraintManager
- : public SimpleConstraintManager {
- GRState::IntSetTy::Factory ISetFactory;
-public:
- BasicConstraintManager(GRStateManager &statemgr, GRSubEngine &subengine)
- : SimpleConstraintManager(subengine),
- ISetFactory(statemgr.getAllocator()) {}
-
- const GRState* AssumeSymNE(const GRState* state, SymbolRef sym,
- const llvm::APSInt& V);
-
- const GRState* AssumeSymEQ(const GRState* state, SymbolRef sym,
- const llvm::APSInt& V);
-
- const GRState* AssumeSymLT(const GRState* state, SymbolRef sym,
- const llvm::APSInt& V);
-
- const GRState* AssumeSymGT(const GRState* state, SymbolRef sym,
- const llvm::APSInt& V);
-
- const GRState* AssumeSymGE(const GRState* state, SymbolRef sym,
- const llvm::APSInt& V);
-
- const GRState* AssumeSymLE(const GRState* state, SymbolRef sym,
- const llvm::APSInt& V);
-
- const GRState* AddEQ(const GRState* state, SymbolRef sym, const llvm::APSInt& V);
-
- const GRState* AddNE(const GRState* state, SymbolRef sym, const llvm::APSInt& V);
-
- const llvm::APSInt* getSymVal(const GRState* state, SymbolRef sym) const;
- bool isNotEqual(const GRState* state, SymbolRef sym, const llvm::APSInt& V)
- const;
- bool isEqual(const GRState* state, SymbolRef sym, const llvm::APSInt& V)
- const;
-
- const GRState* RemoveDeadBindings(const GRState* state, SymbolReaper& SymReaper);
-
- void print(const GRState* state, llvm::raw_ostream& Out,
- const char* nl, const char *sep);
-};
-
-} // end anonymous namespace
-
-ConstraintManager* clang::CreateBasicConstraintManager(GRStateManager& statemgr,
- GRSubEngine &subengine) {
- return new BasicConstraintManager(statemgr, subengine);
-}
-
-const GRState*
-BasicConstraintManager::AssumeSymNE(const GRState *state, SymbolRef sym,
- const llvm::APSInt& V) {
- // First, determine if sym == X, where X != V.
- if (const llvm::APSInt* X = getSymVal(state, sym)) {
- bool isFeasible = (*X != V);
- return isFeasible ? state : NULL;
- }
-
- // Second, determine if sym != V.
- if (isNotEqual(state, sym, V))
- return state;
-
- // If we reach here, sym is not a constant and we don't know if it is != V.
- // Make that assumption.
- return AddNE(state, sym, V);
-}
-
-const GRState *BasicConstraintManager::AssumeSymEQ(const GRState *state,
- SymbolRef sym,
- const llvm::APSInt &V) {
- // First, determine if sym == X, where X != V.
- if (const llvm::APSInt* X = getSymVal(state, sym)) {
- bool isFeasible = *X == V;
- return isFeasible ? state : NULL;
- }
-
- // Second, determine if sym != V.
- if (isNotEqual(state, sym, V))
- return NULL;
-
- // If we reach here, sym is not a constant and we don't know if it is == V.
- // Make that assumption.
- return AddEQ(state, sym, V);
-}
-
-// These logic will be handled in another ConstraintManager.
-const GRState *BasicConstraintManager::AssumeSymLT(const GRState *state,
- SymbolRef sym,
- const llvm::APSInt& V) {
- // Is 'V' the smallest possible value?
- if (V == llvm::APSInt::getMinValue(V.getBitWidth(), V.isUnsigned())) {
- // sym cannot be any value less than 'V'. This path is infeasible.
- return NULL;
- }
-
- // FIXME: For now have assuming x < y be the same as assuming sym != V;
- return AssumeSymNE(state, sym, V);
-}
-
-const GRState *BasicConstraintManager::AssumeSymGT(const GRState *state,
- SymbolRef sym,
- const llvm::APSInt& V) {
-
- // Is 'V' the largest possible value?
- if (V == llvm::APSInt::getMaxValue(V.getBitWidth(), V.isUnsigned())) {
- // sym cannot be any value greater than 'V'. This path is infeasible.
- return NULL;
- }
-
- // FIXME: For now have assuming x > y be the same as assuming sym != V;
- return AssumeSymNE(state, sym, V);
-}
-
-const GRState *BasicConstraintManager::AssumeSymGE(const GRState *state,
- SymbolRef sym,
- const llvm::APSInt &V) {
-
- // Reject a path if the value of sym is a constant X and !(X >= V).
- if (const llvm::APSInt *X = getSymVal(state, sym)) {
- bool isFeasible = *X >= V;
- return isFeasible ? state : NULL;
- }
-
- // Sym is not a constant, but it is worth looking to see if V is the
- // maximum integer value.
- if (V == llvm::APSInt::getMaxValue(V.getBitWidth(), V.isUnsigned())) {
- // If we know that sym != V, then this condition is infeasible since
- // there is no other value greater than V.
- bool isFeasible = !isNotEqual(state, sym, V);
-
- // If the path is still feasible then as a consequence we know that
- // 'sym == V' because we cannot have 'sym > V' (no larger values).
- // Add this constraint.
- return isFeasible ? AddEQ(state, sym, V) : NULL;
- }
-
- return state;
-}
-
-const GRState*
-BasicConstraintManager::AssumeSymLE(const GRState* state, SymbolRef sym,
- const llvm::APSInt& V) {
-
- // Reject a path if the value of sym is a constant X and !(X <= V).
- if (const llvm::APSInt* X = getSymVal(state, sym)) {
- bool isFeasible = *X <= V;
- return isFeasible ? state : NULL;
- }
-
- // Sym is not a constant, but it is worth looking to see if V is the
- // minimum integer value.
- if (V == llvm::APSInt::getMinValue(V.getBitWidth(), V.isUnsigned())) {
- // If we know that sym != V, then this condition is infeasible since
- // there is no other value less than V.
- bool isFeasible = !isNotEqual(state, sym, V);
-
- // If the path is still feasible then as a consequence we know that
- // 'sym == V' because we cannot have 'sym < V' (no smaller values).
- // Add this constraint.
- return isFeasible ? AddEQ(state, sym, V) : NULL;
- }
-
- return state;
-}
-
-const GRState* BasicConstraintManager::AddEQ(const GRState* state, SymbolRef sym,
- const llvm::APSInt& V) {
- // Create a new state with the old binding replaced.
- return state->set<ConstEq>(sym, &V);
-}
-
-const GRState* BasicConstraintManager::AddNE(const GRState* state, SymbolRef sym,
- const llvm::APSInt& V) {
-
- // First, retrieve the NE-set associated with the given symbol.
- ConstNotEqTy::data_type* T = state->get<ConstNotEq>(sym);
- GRState::IntSetTy S = T ? *T : ISetFactory.GetEmptySet();
-
- // Now add V to the NE set.
- S = ISetFactory.Add(S, &V);
-
- // Create a new state with the old binding replaced.
- return state->set<ConstNotEq>(sym, S);
-}
-
-const llvm::APSInt* BasicConstraintManager::getSymVal(const GRState* state,
- SymbolRef sym) const {
- const ConstEqTy::data_type* T = state->get<ConstEq>(sym);
- return T ? *T : NULL;
-}
-
-bool BasicConstraintManager::isNotEqual(const GRState* state, SymbolRef sym,
- const llvm::APSInt& V) const {
-
- // Retrieve the NE-set associated with the given symbol.
- const ConstNotEqTy::data_type* T = state->get<ConstNotEq>(sym);
-
- // See if V is present in the NE-set.
- return T ? T->contains(&V) : false;
-}
-
-bool BasicConstraintManager::isEqual(const GRState* state, SymbolRef sym,
- const llvm::APSInt& V) const {
- // Retrieve the EQ-set associated with the given symbol.
- const ConstEqTy::data_type* T = state->get<ConstEq>(sym);
- // See if V is present in the EQ-set.
- return T ? **T == V : false;
-}
-
-/// Scan all symbols referenced by the constraints. If the symbol is not alive
-/// as marked in LSymbols, mark it as dead in DSymbols.
-const GRState*
-BasicConstraintManager::RemoveDeadBindings(const GRState* state,
- SymbolReaper& SymReaper) {
-
- ConstEqTy CE = state->get<ConstEq>();
- ConstEqTy::Factory& CEFactory = state->get_context<ConstEq>();
-
- for (ConstEqTy::iterator I = CE.begin(), E = CE.end(); I!=E; ++I) {
- SymbolRef sym = I.getKey();
- if (SymReaper.maybeDead(sym)) CE = CEFactory.Remove(CE, sym);
- }
- state = state->set<ConstEq>(CE);
-
- ConstNotEqTy CNE = state->get<ConstNotEq>();
- ConstNotEqTy::Factory& CNEFactory = state->get_context<ConstNotEq>();
-
- for (ConstNotEqTy::iterator I = CNE.begin(), E = CNE.end(); I != E; ++I) {
- SymbolRef sym = I.getKey();
- if (SymReaper.maybeDead(sym)) CNE = CNEFactory.Remove(CNE, sym);
- }
-
- return state->set<ConstNotEq>(CNE);
-}
-
-void BasicConstraintManager::print(const GRState* state, llvm::raw_ostream& Out,
- const char* nl, const char *sep) {
- // Print equality constraints.
-
- ConstEqTy CE = state->get<ConstEq>();
-
- if (!CE.isEmpty()) {
- Out << nl << sep << "'==' constraints:";
- for (ConstEqTy::iterator I = CE.begin(), E = CE.end(); I!=E; ++I)
- Out << nl << " $" << I.getKey() << " : " << *I.getData();
- }
-
- // Print != constraints.
-
- ConstNotEqTy CNE = state->get<ConstNotEq>();
-
- if (!CNE.isEmpty()) {
- Out << nl << sep << "'!=' constraints:";
-
- for (ConstNotEqTy::iterator I = CNE.begin(), EI = CNE.end(); I!=EI; ++I) {
- Out << nl << " $" << I.getKey() << " : ";
- bool isFirst = true;
-
- GRState::IntSetTy::iterator J = I.getData().begin(),
- EJ = I.getData().end();
-
- for ( ; J != EJ; ++J) {
- if (isFirst) isFirst = false;
- else Out << ", ";
-
- Out << (*J)->getSExtValue(); // Hack: should print to raw_ostream.
- }
- }
- }
-}