[clang] 9e842dd - [clang][dataflow] Extend transfer functions for other `CFGElement`s
Wei Yi Tee via cfe-commits
cfe-commits at lists.llvm.org
Wed Aug 31 03:25:45 PDT 2022
Author: Wei Yi Tee
Date: 2022-08-31T10:23:53Z
New Revision: 9e842dd4bd551c42951d1a56bb9d9eef1fa6c385
URL: https://github.com/llvm/llvm-project/commit/9e842dd4bd551c42951d1a56bb9d9eef1fa6c385
DIFF: https://github.com/llvm/llvm-project/commit/9e842dd4bd551c42951d1a56bb9d9eef1fa6c385.diff
LOG: [clang][dataflow] Extend transfer functions for other `CFGElement`s
Previously, the transfer function `void transfer(const Stmt *, ...)` overriden by users is restricted to apply only on `CFGStmt`s and its contained `Stmt`.
By using a transfer function (`void transfer(const CFGElement *, ...)`) that takes a `CFGElement` as input, this patch extends user-defined analysis to all kinds of `CFGElement`. For example, users can now handle `CFGInitializer`s where `CXXCtorInitializer` AST nodes are contained.
Reviewed By: gribozavr2, sgatev
Differential Revision: https://reviews.llvm.org/D131614
Added:
Modified:
clang/include/clang/Analysis/FlowSensitive/DataflowAnalysis.h
clang/include/clang/Analysis/FlowSensitive/TypeErasedDataflowAnalysis.h
clang/lib/Analysis/FlowSensitive/TypeErasedDataflowAnalysis.cpp
clang/unittests/Analysis/FlowSensitive/SingleVarConstantPropagationTest.cpp
clang/unittests/Analysis/FlowSensitive/TestingSupport.h
Removed:
################################################################################
diff --git a/clang/include/clang/Analysis/FlowSensitive/DataflowAnalysis.h b/clang/include/clang/Analysis/FlowSensitive/DataflowAnalysis.h
index 4d1f5248f2115..4e084d57ba011 100644
--- a/clang/include/clang/Analysis/FlowSensitive/DataflowAnalysis.h
+++ b/clang/include/clang/Analysis/FlowSensitive/DataflowAnalysis.h
@@ -15,11 +15,13 @@
#define LLVM_CLANG_ANALYSIS_FLOWSENSITIVE_DATAFLOWANALYSIS_H
#include <iterator>
+#include <type_traits>
#include <utility>
#include <vector>
#include "clang/AST/ASTContext.h"
#include "clang/AST/Stmt.h"
+#include "clang/Analysis/CFG.h"
#include "clang/Analysis/FlowSensitive/ControlFlowContext.h"
#include "clang/Analysis/FlowSensitive/DataflowEnvironment.h"
#include "clang/Analysis/FlowSensitive/TypeErasedDataflowAnalysis.h"
@@ -31,6 +33,17 @@
namespace clang {
namespace dataflow {
+template <typename AnalysisT, typename LatticeT, typename InputT,
+ typename = std::void_t<>>
+struct HasTransferFor : std::false_type {};
+
+template <typename AnalysisT, typename LatticeT, typename InputT>
+struct HasTransferFor<
+ AnalysisT, LatticeT, InputT,
+ std::void_t<decltype(std::declval<AnalysisT>().transfer(
+ std::declval<const InputT *>(), std::declval<LatticeT &>(),
+ std::declval<Environment &>()))>> : std::true_type {};
+
/// Base class template for dataflow analyses built on a single lattice type.
///
/// Requirements:
@@ -39,8 +52,9 @@ namespace dataflow {
/// must provide the following public members:
/// * `LatticeT initialElement()` - returns a lattice element that models the
/// initial state of a basic block;
-/// * `void transfer(const Stmt *, LatticeT &, Environment &)` - applies the
-/// analysis transfer function for a given statement and lattice element.
+/// * `void transfer(const CFGElement *, LatticeT &, Environment &)` - applies
+/// the analysis transfer function for a given CFG element and lattice
+/// element.
///
/// `Derived` can optionally override the following members:
/// * `bool merge(QualType, const Value &, const Value &, Value &,
@@ -93,10 +107,20 @@ class DataflowAnalysis : public TypeErasedDataflowAnalysis {
return L1 == L2;
}
- void transferTypeErased(const Stmt *Stmt, TypeErasedLattice &E,
+ void transferTypeErased(const CFGElement *Element, TypeErasedLattice &E,
Environment &Env) final {
Lattice &L = llvm::any_cast<Lattice &>(E.Value);
- static_cast<Derived *>(this)->transfer(Stmt, L, Env);
+ if constexpr (HasTransferFor<Derived, LatticeT, CFGElement>::value) {
+ static_cast<Derived *>(this)->transfer(Element, L, Env);
+ }
+
+ // FIXME: Remove after users have been updated to implement `transfer` on
+ // `CFGElement`.
+ if constexpr (HasTransferFor<Derived, LatticeT, Stmt>::value) {
+ if (auto Stmt = Element->getAs<CFGStmt>()) {
+ static_cast<Derived *>(this)->transfer(Stmt->getStmt(), L, Env);
+ }
+ }
}
private:
@@ -112,37 +136,41 @@ template <typename LatticeT> struct DataflowAnalysisState {
Environment Env;
};
+// FIXME: Rename to `runDataflowAnalysis` after usages of the overload that
+// applies to `CFGStmt` have been replaced.
+//
/// Performs dataflow analysis and returns a mapping from basic block IDs to
/// dataflow analysis states that model the respective basic blocks. The
/// returned vector, if any, will have the same size as the number of CFG
/// blocks, with indices corresponding to basic block IDs. Returns an error if
/// the dataflow analysis cannot be performed successfully. Otherwise, calls
-/// `PostVisitStmt` on each statement with the final analysis results at that
+/// `PostVisitCFG` on each CFG element with the final analysis results at that
/// program point.
template <typename AnalysisT>
llvm::Expected<std::vector<
llvm::Optional<DataflowAnalysisState<typename AnalysisT::Lattice>>>>
-runDataflowAnalysis(
+runDataflowAnalysisOnCFG(
const ControlFlowContext &CFCtx, AnalysisT &Analysis,
const Environment &InitEnv,
- std::function<void(const CFGStmt &, const DataflowAnalysisState<
- typename AnalysisT::Lattice> &)>
- PostVisitStmt = nullptr) {
- std::function<void(const CFGStmt &, const TypeErasedDataflowAnalysisState &)>
- PostVisitStmtClosure = nullptr;
- if (PostVisitStmt != nullptr) {
- PostVisitStmtClosure = [&PostVisitStmt](
- const CFGStmt &Stmt,
- const TypeErasedDataflowAnalysisState &State) {
+ std::function<void(const CFGElement &, const DataflowAnalysisState<
+ typename AnalysisT::Lattice> &)>
+ PostVisitCFG = nullptr) {
+ std::function<void(const CFGElement &,
+ const TypeErasedDataflowAnalysisState &)>
+ PostVisitCFGClosure = nullptr;
+ if (PostVisitCFG) {
+ PostVisitCFGClosure = [&PostVisitCFG](
+ const CFGElement &Element,
+ const TypeErasedDataflowAnalysisState &State) {
auto *Lattice =
llvm::any_cast<typename AnalysisT::Lattice>(&State.Lattice.Value);
- PostVisitStmt(Stmt, DataflowAnalysisState<typename AnalysisT::Lattice>{
- *Lattice, State.Env});
+ PostVisitCFG(Element, DataflowAnalysisState<typename AnalysisT::Lattice>{
+ *Lattice, State.Env});
};
}
auto TypeErasedBlockStates = runTypeErasedDataflowAnalysis(
- CFCtx, Analysis, InitEnv, PostVisitStmtClosure);
+ CFCtx, Analysis, InitEnv, PostVisitCFGClosure);
if (!TypeErasedBlockStates)
return TypeErasedBlockStates.takeError();
@@ -163,6 +191,41 @@ runDataflowAnalysis(
return BlockStates;
}
+/// Deprecated. Use `runDataflowAnalysisOnCFG` instead.
+///
+/// Performs dataflow analysis and returns a mapping from basic block IDs to
+/// dataflow analysis states that model the respective basic blocks. The
+/// returned vector, if any, will have the same size as the number of CFG
+/// blocks, with indices corresponding to basic block IDs. Returns an error if
+/// the dataflow analysis cannot be performed successfully. Otherwise, calls
+/// `PostVisitStmt` on each statement with the final analysis results at that
+/// program point.
+template <typename AnalysisT>
+llvm::Expected<std::vector<
+ llvm::Optional<DataflowAnalysisState<typename AnalysisT::Lattice>>>>
+runDataflowAnalysis(
+ const ControlFlowContext &CFCtx, AnalysisT &Analysis,
+ const Environment &InitEnv,
+ std::function<void(const CFGStmt &, const DataflowAnalysisState<
+ typename AnalysisT::Lattice> &)>
+ PostVisitStmt = nullptr) {
+ std::function<void(
+ const CFGElement &,
+ const DataflowAnalysisState<typename AnalysisT::Lattice> &)>
+ PostVisitCFG = nullptr;
+ if (PostVisitStmt) {
+ PostVisitCFG =
+ [&PostVisitStmt](
+ const CFGElement &Element,
+ const DataflowAnalysisState<typename AnalysisT::Lattice> &State) {
+ if (auto Stmt = Element.getAs<CFGStmt>()) {
+ PostVisitStmt(*Stmt, State);
+ }
+ };
+ }
+ return runDataflowAnalysisOnCFG(CFCtx, Analysis, InitEnv, PostVisitCFG);
+}
+
/// Abstract base class for dataflow "models": reusable analysis components that
/// model a particular aspect of program semantics in the `Environment`. For
/// example, a model may capture a type and its related functions.
diff --git a/clang/include/clang/Analysis/FlowSensitive/TypeErasedDataflowAnalysis.h b/clang/include/clang/Analysis/FlowSensitive/TypeErasedDataflowAnalysis.h
index 58acda7e6389d..c7dccc36a6a2f 100644
--- a/clang/include/clang/Analysis/FlowSensitive/TypeErasedDataflowAnalysis.h
+++ b/clang/include/clang/Analysis/FlowSensitive/TypeErasedDataflowAnalysis.h
@@ -79,9 +79,9 @@ class TypeErasedDataflowAnalysis : public Environment::ValueModel {
virtual bool isEqualTypeErased(const TypeErasedLattice &,
const TypeErasedLattice &) = 0;
- /// Applies the analysis transfer function for a given statement and
- /// type-erased lattice element.
- virtual void transferTypeErased(const Stmt *, TypeErasedLattice &,
+ /// Applies the analysis transfer function for a given control flow graph
+ /// element and type-erased lattice element.
+ virtual void transferTypeErased(const CFGElement *, TypeErasedLattice &,
Environment &) = 0;
/// If the built-in transfer functions (which model the heap and stack in the
@@ -104,10 +104,10 @@ struct TypeErasedDataflowAnalysisState {
: Lattice(std::move(Lattice)), Env(std::move(Env)) {}
};
-/// Transfers the state of a basic block by evaluating each of its statements in
+/// Transfers the state of a basic block by evaluating each of its elements in
/// the context of `Analysis` and the states of its predecessors that are
-/// available in `BlockStates`. `HandleTransferredStmt` (if provided) will be
-/// applied to each statement in the block, after it is evaluated.
+/// available in `BlockStates`. `PostVisitCFG` (if provided) will be applied to
+/// each element in the block, after it is evaluated.
///
/// Requirements:
///
@@ -119,23 +119,23 @@ TypeErasedDataflowAnalysisState transferBlock(
llvm::ArrayRef<llvm::Optional<TypeErasedDataflowAnalysisState>> BlockStates,
const CFGBlock &Block, const Environment &InitEnv,
TypeErasedDataflowAnalysis &Analysis,
- std::function<void(const CFGStmt &,
+ std::function<void(const CFGElement &,
const TypeErasedDataflowAnalysisState &)>
- HandleTransferredStmt = nullptr);
+ PostVisitCFG = nullptr);
/// Performs dataflow analysis and returns a mapping from basic block IDs to
/// dataflow analysis states that model the respective basic blocks. Indices of
/// the returned vector correspond to basic block IDs. Returns an error if the
/// dataflow analysis cannot be performed successfully. Otherwise, calls
-/// `PostVisitStmt` on each statement with the final analysis results at that
+/// `PostVisitCFG` on each CFG element with the final analysis results at that
/// program point.
llvm::Expected<std::vector<llvm::Optional<TypeErasedDataflowAnalysisState>>>
runTypeErasedDataflowAnalysis(
const ControlFlowContext &CFCtx, TypeErasedDataflowAnalysis &Analysis,
const Environment &InitEnv,
- std::function<void(const CFGStmt &,
+ std::function<void(const CFGElement &,
const TypeErasedDataflowAnalysisState &)>
- PostVisitStmt = nullptr);
+ PostVisitCFG = nullptr);
} // namespace dataflow
} // namespace clang
diff --git a/clang/lib/Analysis/FlowSensitive/TypeErasedDataflowAnalysis.cpp b/clang/lib/Analysis/FlowSensitive/TypeErasedDataflowAnalysis.cpp
index dc2ecef771b69..b85a72a8a7b71 100644
--- a/clang/lib/Analysis/FlowSensitive/TypeErasedDataflowAnalysis.cpp
+++ b/clang/lib/Analysis/FlowSensitive/TypeErasedDataflowAnalysis.cpp
@@ -154,19 +154,37 @@ class TerminatorVisitor : public ConstStmtVisitor<TerminatorVisitor> {
TransferOptions TransferOpts;
};
+/// Holds data structures required for running dataflow analysis.
+struct AnalysisContext {
+ AnalysisContext(
+ const ControlFlowContext &CFCtx, TypeErasedDataflowAnalysis &Analysis,
+ const Environment &InitEnv,
+ llvm::ArrayRef<llvm::Optional<TypeErasedDataflowAnalysisState>>
+ BlockStates)
+ : CFCtx(CFCtx), Analysis(Analysis), InitEnv(InitEnv),
+ BlockStates(BlockStates) {}
+
+ /// Contains the CFG being analyzed.
+ const ControlFlowContext &CFCtx;
+ /// The analysis to be run.
+ TypeErasedDataflowAnalysis &Analysis;
+ /// Initial state to start the analysis.
+ const Environment &InitEnv;
+ /// Stores the state of a CFG block if it has been evaluated by the analysis.
+ /// The indices correspond to the block IDs.
+ llvm::ArrayRef<llvm::Optional<TypeErasedDataflowAnalysisState>> BlockStates;
+};
+
/// Computes the input state for a given basic block by joining the output
/// states of its predecessors.
///
/// Requirements:
///
/// All predecessors of `Block` except those with loop back edges must have
-/// already been transferred. States in `BlockStates` that are set to
+/// already been transferred. States in `AC.BlockStates` that are set to
/// `llvm::None` represent basic blocks that are not evaluated yet.
-static TypeErasedDataflowAnalysisState computeBlockInputState(
- const ControlFlowContext &CFCtx,
- llvm::ArrayRef<llvm::Optional<TypeErasedDataflowAnalysisState>> BlockStates,
- const CFGBlock &Block, const Environment &InitEnv,
- TypeErasedDataflowAnalysis &Analysis) {
+static TypeErasedDataflowAnalysisState
+computeBlockInputState(const CFGBlock &Block, AnalysisContext &AC) {
llvm::DenseSet<const CFGBlock *> Preds;
Preds.insert(Block.pred_begin(), Block.pred_end());
if (Block.getTerminator().isTemporaryDtorsBranch()) {
@@ -193,13 +211,16 @@ static TypeErasedDataflowAnalysisState computeBlockInputState(
//
// See `NoreturnDestructorTest` for concrete examples.
if (Block.succ_begin()->getReachableBlock()->hasNoReturnElement()) {
- auto StmtBlock = CFCtx.getStmtToBlock().find(Block.getTerminatorStmt());
- assert(StmtBlock != CFCtx.getStmtToBlock().end());
+ auto &StmtToBlock = AC.CFCtx.getStmtToBlock();
+ auto StmtBlock = StmtToBlock.find(Block.getTerminatorStmt());
+ assert(StmtBlock != StmtToBlock.end());
Preds.erase(StmtBlock->getSecond());
}
}
llvm::Optional<TypeErasedDataflowAnalysisState> MaybeState;
+
+ auto &Analysis = AC.Analysis;
auto BuiltinTransferOpts = Analysis.builtinTransferOptions();
for (const CFGBlock *Pred : Preds) {
@@ -210,14 +231,14 @@ static TypeErasedDataflowAnalysisState computeBlockInputState(
// Skip if `Pred` was not evaluated yet. This could happen if `Pred` has a
// loop back edge to `Block`.
const llvm::Optional<TypeErasedDataflowAnalysisState> &MaybePredState =
- BlockStates[Pred->getBlockID()];
+ AC.BlockStates[Pred->getBlockID()];
if (!MaybePredState)
continue;
TypeErasedDataflowAnalysisState PredState = MaybePredState.value();
if (BuiltinTransferOpts) {
if (const Stmt *PredTerminatorStmt = Pred->getTerminatorStmt()) {
- const StmtToEnvMapImpl StmtToEnv(CFCtx, BlockStates);
+ const StmtToEnvMapImpl StmtToEnv(AC.CFCtx, AC.BlockStates);
TerminatorVisitor(StmtToEnv, PredState.Env,
blockIndexInPredecessor(*Pred, Block),
*BuiltinTransferOpts)
@@ -236,107 +257,125 @@ static TypeErasedDataflowAnalysisState computeBlockInputState(
// FIXME: Consider passing `Block` to `Analysis.typeErasedInitialElement()`
// to enable building analyses like computation of dominators that
// initialize the state of each basic block
diff erently.
- MaybeState.emplace(Analysis.typeErasedInitialElement(), InitEnv);
+ MaybeState.emplace(Analysis.typeErasedInitialElement(), AC.InitEnv);
}
return *MaybeState;
}
-/// Transfers `State` by evaluating `CfgStmt` in the context of `Analysis`.
-/// `HandleTransferredStmt` (if provided) will be applied to `CfgStmt`, after it
-/// is evaluated.
-static void transferCFGStmt(
- const ControlFlowContext &CFCtx,
- llvm::ArrayRef<llvm::Optional<TypeErasedDataflowAnalysisState>> BlockStates,
- const CFGStmt &CfgStmt, TypeErasedDataflowAnalysis &Analysis,
- TypeErasedDataflowAnalysisState &State,
- std::function<void(const CFGStmt &,
- const TypeErasedDataflowAnalysisState &)>
- HandleTransferredStmt) {
- const Stmt *S = CfgStmt.getStmt();
+/// Built-in transfer function for `CFGStmt`.
+void builtinTransferStatement(const CFGStmt &Elt,
+ TypeErasedDataflowAnalysisState &InputState,
+ AnalysisContext &AC) {
+ const Stmt *S = Elt.getStmt();
assert(S != nullptr);
-
- auto BuiltinTransferOpts = Analysis.builtinTransferOptions();
- if (BuiltinTransferOpts)
- transfer(StmtToEnvMapImpl(CFCtx, BlockStates), *S, State.Env,
- *BuiltinTransferOpts);
- Analysis.transferTypeErased(S, State.Lattice, State.Env);
-
- if (HandleTransferredStmt != nullptr)
- HandleTransferredStmt(CfgStmt, State);
+ transfer(StmtToEnvMapImpl(AC.CFCtx, AC.BlockStates), *S, InputState.Env,
+ *AC.Analysis.builtinTransferOptions());
}
-/// Transfers `State` by evaluating `CfgInit`.
-static void transferCFGInitializer(const CFGInitializer &CfgInit,
- TypeErasedDataflowAnalysisState &State) {
- const auto &ThisLoc = *cast<AggregateStorageLocation>(
- State.Env.getThisPointeeStorageLocation());
+/// Built-in transfer function for `CFGInitializer`.
+void builtinTransferInitializer(const CFGInitializer &Elt,
+ TypeErasedDataflowAnalysisState &InputState) {
+ const CXXCtorInitializer *Init = Elt.getInitializer();
+ assert(Init != nullptr);
- const CXXCtorInitializer *Initializer = CfgInit.getInitializer();
- assert(Initializer != nullptr);
+ auto &Env = InputState.Env;
+ const auto &ThisLoc =
+ *cast<AggregateStorageLocation>(Env.getThisPointeeStorageLocation());
- const FieldDecl *Member = Initializer->getMember();
+ const FieldDecl *Member = Init->getMember();
if (Member == nullptr)
// Not a field initializer.
return;
- auto *InitStmt = Initializer->getInit();
+ auto *InitStmt = Init->getInit();
assert(InitStmt != nullptr);
- auto *InitStmtLoc =
- State.Env.getStorageLocation(*InitStmt, SkipPast::Reference);
+ auto *InitStmtLoc = Env.getStorageLocation(*InitStmt, SkipPast::Reference);
if (InitStmtLoc == nullptr)
return;
- auto *InitStmtVal = State.Env.getValue(*InitStmtLoc);
+ auto *InitStmtVal = Env.getValue(*InitStmtLoc);
if (InitStmtVal == nullptr)
return;
if (Member->getType()->isReferenceType()) {
auto &MemberLoc = ThisLoc.getChild(*Member);
- State.Env.setValue(MemberLoc,
- State.Env.takeOwnership(
- std::make_unique<ReferenceValue>(*InitStmtLoc)));
+ Env.setValue(MemberLoc, Env.takeOwnership(std::make_unique<ReferenceValue>(
+ *InitStmtLoc)));
} else {
auto &MemberLoc = ThisLoc.getChild(*Member);
- State.Env.setValue(MemberLoc, *InitStmtVal);
+ Env.setValue(MemberLoc, *InitStmtVal);
+ }
+}
+
+void builtinTransfer(const CFGElement &Elt,
+ TypeErasedDataflowAnalysisState &State,
+ AnalysisContext &AC) {
+ switch (Elt.getKind()) {
+ case CFGElement::Statement: {
+ builtinTransferStatement(Elt.castAs<CFGStmt>(), State, AC);
+ break;
+ }
+ case CFGElement::Initializer: {
+ builtinTransferInitializer(Elt.castAs<CFGInitializer>(), State);
+ break;
+ }
+ default:
+ // FIXME: Evaluate other kinds of `CFGElement`.
+ break;
}
}
+/// Transfers `State` by evaluating each element in the `Block` based on the
+/// `AC.Analysis` specified.
+///
+/// Built-in transfer functions (if the option for `ApplyBuiltinTransfer` is set
+/// by the analysis) will be applied to the element before evaluation by the
+/// user-specified analysis.
+/// `PostVisitCFG` (if provided) will be applied to the element after evaluation
+/// by the user-specified analysis.
+TypeErasedDataflowAnalysisState
+transferCFGBlock(const CFGBlock &Block, AnalysisContext &AC,
+ std::function<void(const CFGElement &,
+ const TypeErasedDataflowAnalysisState &)>
+ PostVisitCFG = nullptr) {
+ auto State = computeBlockInputState(Block, AC);
+ for (const auto &Element : Block) {
+ // Built-in analysis
+ if (AC.Analysis.builtinTransferOptions()) {
+ builtinTransfer(Element, State, AC);
+ }
+
+ // User-provided analysis
+ AC.Analysis.transferTypeErased(&Element, State.Lattice, State.Env);
+
+ // Post processing
+ if (PostVisitCFG) {
+ PostVisitCFG(Element, State);
+ }
+ }
+ return State;
+}
+
TypeErasedDataflowAnalysisState transferBlock(
const ControlFlowContext &CFCtx,
llvm::ArrayRef<llvm::Optional<TypeErasedDataflowAnalysisState>> BlockStates,
const CFGBlock &Block, const Environment &InitEnv,
TypeErasedDataflowAnalysis &Analysis,
- std::function<void(const CFGStmt &,
+ std::function<void(const CFGElement &,
const TypeErasedDataflowAnalysisState &)>
- HandleTransferredStmt) {
- TypeErasedDataflowAnalysisState State =
- computeBlockInputState(CFCtx, BlockStates, Block, InitEnv, Analysis);
- for (const CFGElement &Element : Block) {
- switch (Element.getKind()) {
- case CFGElement::Statement:
- transferCFGStmt(CFCtx, BlockStates, *Element.getAs<CFGStmt>(), Analysis,
- State, HandleTransferredStmt);
- break;
- case CFGElement::Initializer:
- if (Analysis.builtinTransferOptions())
- transferCFGInitializer(*Element.getAs<CFGInitializer>(), State);
- break;
- default:
- // FIXME: Evaluate other kinds of `CFGElement`.
- break;
- }
- }
- return State;
+ PostVisitCFG) {
+ AnalysisContext AC(CFCtx, Analysis, InitEnv, BlockStates);
+ return transferCFGBlock(Block, AC, PostVisitCFG);
}
llvm::Expected<std::vector<llvm::Optional<TypeErasedDataflowAnalysisState>>>
runTypeErasedDataflowAnalysis(
const ControlFlowContext &CFCtx, TypeErasedDataflowAnalysis &Analysis,
const Environment &InitEnv,
- std::function<void(const CFGStmt &,
+ std::function<void(const CFGElement &,
const TypeErasedDataflowAnalysisState &)>
- PostVisitStmt) {
+ PostVisitCFG) {
PostOrderCFGView POV(&CFCtx.getCFG());
ForwardDataflowWorklist Worklist(CFCtx.getCFG(), &POV);
@@ -349,6 +388,8 @@ runTypeErasedDataflowAnalysis(
InitEnv};
Worklist.enqueueSuccessors(&Entry);
+ AnalysisContext AC(CFCtx, Analysis, InitEnv, BlockStates);
+
// Bugs in lattices and transfer functions can prevent the analysis from
// converging. To limit the damage (infinite loops) that these bugs can cause,
// limit the number of iterations.
@@ -373,7 +414,7 @@ runTypeErasedDataflowAnalysis(
const llvm::Optional<TypeErasedDataflowAnalysisState> &OldBlockState =
BlockStates[Block->getBlockID()];
TypeErasedDataflowAnalysisState NewBlockState =
- transferBlock(CFCtx, BlockStates, *Block, InitEnv, Analysis);
+ transferCFGBlock(*Block, AC);
if (OldBlockState &&
Analysis.isEqualTypeErased(OldBlockState.value().Lattice,
@@ -395,14 +436,12 @@ runTypeErasedDataflowAnalysis(
// FIXME: Consider evaluating unreachable basic blocks (those that have a
// state set to `llvm::None` at this point) to also analyze dead code.
- if (PostVisitStmt) {
+ if (PostVisitCFG) {
for (const CFGBlock *Block : CFCtx.getCFG()) {
// Skip blocks that were not evaluated.
if (!BlockStates[Block->getBlockID()])
continue;
-
- transferBlock(CFCtx, BlockStates, *Block, InitEnv, Analysis,
- PostVisitStmt);
+ transferCFGBlock(*Block, AC, PostVisitCFG);
}
}
diff --git a/clang/unittests/Analysis/FlowSensitive/SingleVarConstantPropagationTest.cpp b/clang/unittests/Analysis/FlowSensitive/SingleVarConstantPropagationTest.cpp
index 3c95ead0ab8a0..664950065844d 100644
--- a/clang/unittests/Analysis/FlowSensitive/SingleVarConstantPropagationTest.cpp
+++ b/clang/unittests/Analysis/FlowSensitive/SingleVarConstantPropagationTest.cpp
@@ -194,8 +194,8 @@ void RunDataflow(llvm::StringRef Code, Matcher Expectations) {
},
[&Expectations](
llvm::ArrayRef<std::pair<
- std::string, DataflowAnalysisState<
- ConstantPropagationAnalysis::Lattice>>>
+ std::string,
+ DataflowAnalysisState<ConstantPropagationAnalysis::Lattice>>>
Results,
ASTContext &) { EXPECT_THAT(Results, Expectations); },
{"-fsyntax-only", "-std=c++17"}),
diff --git a/clang/unittests/Analysis/FlowSensitive/TestingSupport.h b/clang/unittests/Analysis/FlowSensitive/TestingSupport.h
index f09d5f9db21ad..cdcf61ee22577 100644
--- a/clang/unittests/Analysis/FlowSensitive/TestingSupport.h
+++ b/clang/unittests/Analysis/FlowSensitive/TestingSupport.h
@@ -71,14 +71,25 @@ struct AnalysisData {
std::vector<llvm::Optional<TypeErasedDataflowAnalysisState>> &BlockStates;
};
+// FIXME: Rename to `checkDataflow` after usages of the overload that applies to
+// `CFGStmt` have been replaced.
+//
+/// Runs dataflow analysis (specified from `MakeAnalysis`) and the
+/// `PostVisitCFG` function (if provided) on the body of the function that
+/// matches `TargetFuncMatcher` in code snippet `Code`. `VerifyResults` checks
+/// that the results from the analysis are correct.
+///
+/// Requirements:
+///
+/// `AnalysisT` contains a type `Lattice`.
template <typename AnalysisT>
-llvm::Error checkDataflow(
+llvm::Error checkDataflowOnCFG(
llvm::StringRef Code,
ast_matchers::internal::Matcher<FunctionDecl> TargetFuncMatcher,
std::function<AnalysisT(ASTContext &, Environment &)> MakeAnalysis,
- std::function<void(ASTContext &, const CFGStmt &,
+ std::function<void(ASTContext &, const CFGElement &,
const TypeErasedDataflowAnalysisState &)>
- PostVisitStmt,
+ PostVisitCFG,
std::function<void(AnalysisData)> VerifyResults, ArrayRef<std::string> Args,
const tooling::FileContentMappings &VirtualMappedFiles = {}) {
llvm::Annotations AnnotatedCode(Code);
@@ -112,13 +123,14 @@ llvm::Error checkDataflow(
Environment Env(DACtx, *F);
auto Analysis = MakeAnalysis(Context, Env);
- std::function<void(const CFGStmt &, const TypeErasedDataflowAnalysisState &)>
- PostVisitStmtClosure = nullptr;
- if (PostVisitStmt != nullptr) {
- PostVisitStmtClosure = [&PostVisitStmt, &Context](
- const CFGStmt &Stmt,
- const TypeErasedDataflowAnalysisState &State) {
- PostVisitStmt(Context, Stmt, State);
+ std::function<void(const CFGElement &,
+ const TypeErasedDataflowAnalysisState &)>
+ PostVisitCFGClosure = nullptr;
+ if (PostVisitCFG) {
+ PostVisitCFGClosure = [&PostVisitCFG, &Context](
+ const CFGElement &Element,
+ const TypeErasedDataflowAnalysisState &State) {
+ PostVisitCFG(Context, Element, State);
};
}
@@ -130,7 +142,7 @@ llvm::Error checkDataflow(
llvm::Expected<std::vector<llvm::Optional<TypeErasedDataflowAnalysisState>>>
MaybeBlockStates = runTypeErasedDataflowAnalysis(*CFCtx, Analysis, Env,
- PostVisitStmtClosure);
+ PostVisitCFGClosure);
if (!MaybeBlockStates)
return MaybeBlockStates.takeError();
auto &BlockStates = *MaybeBlockStates;
@@ -141,6 +153,32 @@ llvm::Error checkDataflow(
return llvm::Error::success();
}
+template <typename AnalysisT>
+llvm::Error checkDataflow(
+ llvm::StringRef Code,
+ ast_matchers::internal::Matcher<FunctionDecl> TargetFuncMatcher,
+ std::function<AnalysisT(ASTContext &, Environment &)> MakeAnalysis,
+ std::function<void(ASTContext &, const CFGStmt &,
+ const TypeErasedDataflowAnalysisState &)>
+ PostVisitStmt,
+ std::function<void(AnalysisData)> VerifyResults, ArrayRef<std::string> Args,
+ const tooling::FileContentMappings &VirtualMappedFiles = {}) {
+ std::function<void(ASTContext & Context, const CFGElement &,
+ const TypeErasedDataflowAnalysisState &)>
+ PostVisitCFG = nullptr;
+ if (PostVisitStmt) {
+ PostVisitCFG =
+ [&PostVisitStmt](ASTContext &Context, const CFGElement &Element,
+ const TypeErasedDataflowAnalysisState &State) {
+ if (auto Stmt = Element.getAs<CFGStmt>()) {
+ PostVisitStmt(Context, *Stmt, State);
+ }
+ };
+ }
+ return checkDataflowOnCFG(Code, TargetFuncMatcher, MakeAnalysis, PostVisitCFG,
+ VerifyResults, Args, VirtualMappedFiles);
+}
+
// Runs dataflow on the body of the function that matches `TargetFuncMatcher` in
// code snippet `Code`. Requires: `AnalysisT` contains a type `Lattice`.
template <typename AnalysisT>
@@ -157,9 +195,9 @@ llvm::Error checkDataflow(
const tooling::FileContentMappings &VirtualMappedFiles = {}) {
using StateT = DataflowAnalysisState<typename AnalysisT::Lattice>;
- return checkDataflow(
+ return checkDataflowOnCFG(
Code, std::move(TargetFuncMatcher), std::move(MakeAnalysis),
- /*PostVisitStmt=*/nullptr,
+ /*PostVisitCFG=*/nullptr,
[&VerifyResults](AnalysisData AnalysisData) {
if (AnalysisData.BlockStates.empty()) {
VerifyResults({}, AnalysisData.ASTCtx);
@@ -180,9 +218,13 @@ llvm::Error checkDataflow(
AnalysisData.CFCtx, AnalysisData.BlockStates, *Block,
AnalysisData.Env, AnalysisData.Analysis,
[&Results,
- &Annotations](const clang::CFGStmt &Stmt,
+ &Annotations](const clang::CFGElement &Element,
const TypeErasedDataflowAnalysisState &State) {
- auto It = Annotations.find(Stmt.getStmt());
+ // FIXME: Extend testing annotations to non statement constructs
+ auto Stmt = Element.getAs<CFGStmt>();
+ if (!Stmt)
+ return;
+ auto It = Annotations.find(Stmt->getStmt());
if (It == Annotations.end())
return;
auto *Lattice = llvm::any_cast<typename AnalysisT::Lattice>(
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