r217556 - Thread Safety Analysis: major update to thread safety TIL.
DeLesley Hutchins
delesley at google.com
Wed Sep 10 15:12:52 PDT 2014
Author: delesley
Date: Wed Sep 10 17:12:52 2014
New Revision: 217556
URL: http://llvm.org/viewvc/llvm-project?rev=217556&view=rev
Log:
Thread Safety Analysis: major update to thread safety TIL.
Numerous changes, including:
* Changed the way variables and instructions are handled in basic blocks to
be more efficient.
* Eliminated SExprRef.
* Simplified futures.
* Fixed documentation.
* Compute dominator and post dominator trees.
Modified:
cfe/trunk/include/clang/Analysis/Analyses/ThreadSafetyCommon.h
cfe/trunk/include/clang/Analysis/Analyses/ThreadSafetyLogical.h
cfe/trunk/include/clang/Analysis/Analyses/ThreadSafetyOps.def
cfe/trunk/include/clang/Analysis/Analyses/ThreadSafetyTIL.h
cfe/trunk/include/clang/Analysis/Analyses/ThreadSafetyTraverse.h
cfe/trunk/include/clang/Analysis/Analyses/ThreadSafetyUtil.h
cfe/trunk/lib/Analysis/ThreadSafetyCommon.cpp
cfe/trunk/lib/Analysis/ThreadSafetyTIL.cpp
Modified: cfe/trunk/include/clang/Analysis/Analyses/ThreadSafetyCommon.h
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/include/clang/Analysis/Analyses/ThreadSafetyCommon.h?rev=217556&r1=217555&r2=217556&view=diff
==============================================================================
--- cfe/trunk/include/clang/Analysis/Analyses/ThreadSafetyCommon.h (original)
+++ cfe/trunk/include/clang/Analysis/Analyses/ThreadSafetyCommon.h Wed Sep 10 17:12:52 2014
@@ -477,9 +477,9 @@ private:
// Indexed by clang BlockID.
LVarDefinitionMap CurrentLVarMap;
- std::vector<til::Variable*> CurrentArguments;
- std::vector<til::Variable*> CurrentInstructions;
- std::vector<til::Variable*> IncompleteArgs;
+ std::vector<til::Phi*> CurrentArguments;
+ std::vector<til::SExpr*> CurrentInstructions;
+ std::vector<til::Phi*> IncompleteArgs;
til::BasicBlock *CurrentBB;
BlockInfo *CurrentBlockInfo;
};
Modified: cfe/trunk/include/clang/Analysis/Analyses/ThreadSafetyLogical.h
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/include/clang/Analysis/Analyses/ThreadSafetyLogical.h?rev=217556&r1=217555&r2=217556&view=diff
==============================================================================
--- cfe/trunk/include/clang/Analysis/Analyses/ThreadSafetyLogical.h (original)
+++ cfe/trunk/include/clang/Analysis/Analyses/ThreadSafetyLogical.h Wed Sep 10 17:12:52 2014
@@ -41,13 +41,13 @@ private:
};
class Terminal : public LExpr {
- til::SExprRef Expr;
+ til::SExpr *Expr;
public:
Terminal(til::SExpr *Expr) : LExpr(LExpr::Terminal), Expr(Expr) {}
- const til::SExpr *expr() const { return Expr.get(); }
- til::SExpr *expr() { return Expr.get(); }
+ const til::SExpr *expr() const { return Expr; }
+ til::SExpr *expr() { return Expr; }
static bool classof(const LExpr *E) { return E->kind() == LExpr::Terminal; }
};
Modified: cfe/trunk/include/clang/Analysis/Analyses/ThreadSafetyOps.def
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/include/clang/Analysis/Analyses/ThreadSafetyOps.def?rev=217556&r1=217555&r2=217556&view=diff
==============================================================================
--- cfe/trunk/include/clang/Analysis/Analyses/ThreadSafetyOps.def (original)
+++ cfe/trunk/include/clang/Analysis/Analyses/ThreadSafetyOps.def Wed Sep 10 17:12:52 2014
@@ -44,8 +44,11 @@ TIL_OPCODE_DEF(Cast)
TIL_OPCODE_DEF(SCFG)
TIL_OPCODE_DEF(BasicBlock)
TIL_OPCODE_DEF(Phi)
+
+// Terminator instructions
TIL_OPCODE_DEF(Goto)
TIL_OPCODE_DEF(Branch)
+TIL_OPCODE_DEF(Return)
// pseudo-terms
TIL_OPCODE_DEF(Identifier)
Modified: cfe/trunk/include/clang/Analysis/Analyses/ThreadSafetyTIL.h
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/include/clang/Analysis/Analyses/ThreadSafetyTIL.h?rev=217556&r1=217555&r2=217556&view=diff
==============================================================================
--- cfe/trunk/include/clang/Analysis/Analyses/ThreadSafetyTIL.h (original)
+++ cfe/trunk/include/clang/Analysis/Analyses/ThreadSafetyTIL.h Wed Sep 10 17:12:52 2014
@@ -63,24 +63,27 @@ namespace threadSafety {
namespace til {
+/// Enum for the different distinct classes of SExpr
enum TIL_Opcode {
#define TIL_OPCODE_DEF(X) COP_##X,
#include "ThreadSafetyOps.def"
#undef TIL_OPCODE_DEF
};
+/// Opcode for unary arithmetic operations.
enum TIL_UnaryOpcode : unsigned char {
UOP_Minus, // -
UOP_BitNot, // ~
UOP_LogicNot // !
};
+/// Opcode for binary arithmetic operations.
enum TIL_BinaryOpcode : unsigned char {
+ BOP_Add, // +
+ BOP_Sub, // -
BOP_Mul, // *
BOP_Div, // /
BOP_Rem, // %
- BOP_Add, // +
- BOP_Sub, // -
BOP_Shl, // <<
BOP_Shr, // >>
BOP_BitAnd, // &
@@ -90,10 +93,11 @@ enum TIL_BinaryOpcode : unsigned char {
BOP_Neq, // !=
BOP_Lt, // <
BOP_Leq, // <=
- BOP_LogicAnd, // &&
- BOP_LogicOr // ||
+ BOP_LogicAnd, // && (no short-circuit)
+ BOP_LogicOr // || (no short-circuit)
};
+/// Opcode for cast operations.
enum TIL_CastOpcode : unsigned char {
CAST_none = 0,
CAST_extendNum, // extend precision of numeric type
@@ -107,21 +111,24 @@ const TIL_Opcode COP_Min = COP_Fu
const TIL_Opcode COP_Max = COP_Branch;
const TIL_UnaryOpcode UOP_Min = UOP_Minus;
const TIL_UnaryOpcode UOP_Max = UOP_LogicNot;
-const TIL_BinaryOpcode BOP_Min = BOP_Mul;
+const TIL_BinaryOpcode BOP_Min = BOP_Add;
const TIL_BinaryOpcode BOP_Max = BOP_LogicOr;
const TIL_CastOpcode CAST_Min = CAST_none;
const TIL_CastOpcode CAST_Max = CAST_toInt;
+/// Return the name of a unary opcode.
StringRef getUnaryOpcodeString(TIL_UnaryOpcode Op);
+
+/// Return the name of a binary opcode.
StringRef getBinaryOpcodeString(TIL_BinaryOpcode Op);
-// ValueTypes are data types that can actually be held in registers.
-// All variables and expressions must have a vBNF_Nonealue type.
-// Pointer types are further subdivided into the various heap-allocated
-// types, such as functions, records, etc.
-// Structured types that are passed by value (e.g. complex numbers)
-// require special handling; they use BT_ValueRef, and size ST_0.
+/// ValueTypes are data types that can actually be held in registers.
+/// All variables and expressions must have a value type.
+/// Pointer types are further subdivided into the various heap-allocated
+/// types, such as functions, records, etc.
+/// Structured types that are passed by value (e.g. complex numbers)
+/// require special handling; they use BT_ValueRef, and size ST_0.
struct ValueType {
enum BaseType : unsigned char {
BT_Void = 0,
@@ -247,8 +254,10 @@ inline ValueType ValueType::getValueType
}
+class BasicBlock;
+
-// Base class for AST nodes in the typed intermediate language.
+/// Base class for AST nodes in the typed intermediate language.
class SExpr {
public:
TIL_Opcode opcode() const { return static_cast<TIL_Opcode>(Opcode); }
@@ -267,71 +276,47 @@ public:
// template <class C> typename C::CType compare(CType* E, C& Cmp) {
// compare all subexpressions, following the comparator interface
// }
-
void *operator new(size_t S, MemRegionRef &R) {
return ::operator new(S, R);
}
- // SExpr objects cannot be deleted.
+ /// SExpr objects cannot be deleted.
// This declaration is public to workaround a gcc bug that breaks building
// with REQUIRES_EH=1.
void operator delete(void *) LLVM_DELETED_FUNCTION;
+ /// Returns the instruction ID for this expression.
+ /// All basic block instructions have a unique ID (i.e. virtual register).
+ unsigned id() const { return SExprID; }
+
+ /// Returns the block, if this is an instruction in a basic block,
+ /// otherwise returns null.
+ BasicBlock* block() const { return Block; }
+
+ /// Set the basic block and instruction ID for this expression.
+ void setID(BasicBlock *B, unsigned id) { Block = B; SExprID = id; }
+
protected:
- SExpr(TIL_Opcode Op) : Opcode(Op), Reserved(0), Flags(0) {}
- SExpr(const SExpr &E) : Opcode(E.Opcode), Reserved(0), Flags(E.Flags) {}
+ SExpr(TIL_Opcode Op)
+ : Opcode(Op), Reserved(0), Flags(0), SExprID(0), Block(nullptr) {}
+ SExpr(const SExpr &E)
+ : Opcode(E.Opcode), Reserved(0), Flags(E.Flags), SExprID(0),
+ Block(nullptr) {}
const unsigned char Opcode;
unsigned char Reserved;
unsigned short Flags;
+ unsigned SExprID;
+ BasicBlock* Block;
private:
SExpr() LLVM_DELETED_FUNCTION;
- // SExpr objects must be created in an arena.
+ /// SExpr objects must be created in an arena.
void *operator new(size_t) LLVM_DELETED_FUNCTION;
};
-// Class for owning references to SExprs.
-// Includes attach/detach logic for counting variable references and lazy
-// rewriting strategies.
-class SExprRef {
-public:
- SExprRef() : Ptr(nullptr) { }
- SExprRef(std::nullptr_t P) : Ptr(nullptr) { }
- SExprRef(SExprRef &&R) : Ptr(R.Ptr) { R.Ptr = nullptr; }
-
- // Defined after Variable and Future, below.
- inline SExprRef(SExpr *P);
- inline ~SExprRef();
-
- SExpr *get() { return Ptr; }
- const SExpr *get() const { return Ptr; }
-
- SExpr *operator->() { return get(); }
- const SExpr *operator->() const { return get(); }
-
- SExpr &operator*() { return *Ptr; }
- const SExpr &operator*() const { return *Ptr; }
-
- bool operator==(const SExprRef &R) const { return Ptr == R.Ptr; }
- bool operator!=(const SExprRef &R) const { return !operator==(R); }
- bool operator==(const SExpr *P) const { return Ptr == P; }
- bool operator!=(const SExpr *P) const { return !operator==(P); }
- bool operator==(std::nullptr_t) const { return Ptr == nullptr; }
- bool operator!=(std::nullptr_t) const { return Ptr != nullptr; }
-
- inline void reset(SExpr *E);
-
-private:
- inline void attach();
- inline void detach();
-
- SExpr *Ptr;
-};
-
-
// Contains various helper functions for SExprs.
namespace ThreadSafetyTIL {
inline bool isTrivial(const SExpr *E) {
@@ -343,62 +328,64 @@ namespace ThreadSafetyTIL {
// Nodes which declare variables
class Function;
class SFunction;
-class BasicBlock;
class Let;
-// A named variable, e.g. "x".
-//
-// There are two distinct places in which a Variable can appear in the AST.
-// A variable declaration introduces a new variable, and can occur in 3 places:
-// Let-expressions: (Let (x = t) u)
-// Functions: (Function (x : t) u)
-// Self-applicable functions (SFunction (x) t)
-//
-// If a variable occurs in any other location, it is a reference to an existing
-// variable declaration -- e.g. 'x' in (x * y + z). To save space, we don't
-// allocate a separate AST node for variable references; a reference is just a
-// pointer to the original declaration.
+/// A named variable, e.g. "x".
+///
+/// There are two distinct places in which a Variable can appear in the AST.
+/// A variable declaration introduces a new variable, and can occur in 3 places:
+/// Let-expressions: (Let (x = t) u)
+/// Functions: (Function (x : t) u)
+/// Self-applicable functions (SFunction (x) t)
+///
+/// If a variable occurs in any other location, it is a reference to an existing
+/// variable declaration -- e.g. 'x' in (x * y + z). To save space, we don't
+/// allocate a separate AST node for variable references; a reference is just a
+/// pointer to the original declaration.
class Variable : public SExpr {
public:
static bool classof(const SExpr *E) { return E->opcode() == COP_Variable; }
- // Let-variable, function parameter, or self-variable
enum VariableKind {
- VK_Let,
- VK_LetBB,
- VK_Fun,
- VK_SFun
+ VK_Let, ///< Let-variable
+ VK_Fun, ///< Function parameter
+ VK_SFun ///< SFunction (self) parameter
};
- // These are defined after SExprRef contructor, below
- inline Variable(SExpr *D, const clang::ValueDecl *Cvd = nullptr);
- inline Variable(StringRef s, SExpr *D = nullptr);
- inline Variable(const Variable &Vd, SExpr *D);
+ Variable(StringRef s, SExpr *D = nullptr)
+ : SExpr(COP_Variable), Name(s), Definition(D), Cvdecl(nullptr) {
+ Flags = VK_Let;
+ }
+ Variable(SExpr *D, const clang::ValueDecl *Cvd = nullptr)
+ : SExpr(COP_Variable), Name(Cvd ? Cvd->getName() : "_x"),
+ Definition(D), Cvdecl(Cvd) {
+ Flags = VK_Let;
+ }
+ Variable(const Variable &Vd, SExpr *D) // rewrite constructor
+ : SExpr(Vd), Name(Vd.Name), Definition(D), Cvdecl(Vd.Cvdecl) {
+ Flags = Vd.kind();
+ }
+ /// Return the kind of variable (let, function param, or self)
VariableKind kind() const { return static_cast<VariableKind>(Flags); }
+ /// Return the name of the variable, if any.
StringRef name() const { return Name; }
+
+ /// Return the clang declaration for this variable, if any.
const clang::ValueDecl *clangDecl() const { return Cvdecl; }
- // Returns the definition (for let vars) or type (for parameter & self vars)
- SExpr *definition() { return Definition.get(); }
- const SExpr *definition() const { return Definition.get(); }
-
- void attachVar() const { ++NumUses; }
- void detachVar() const { assert(NumUses > 0); --NumUses; }
-
- unsigned getID() const { return Id; }
- unsigned getBlockID() const { return BlockID; }
-
- void setName(StringRef S) { Name = S; }
- void setID(unsigned Bid, unsigned I) {
- BlockID = static_cast<unsigned short>(Bid);
- Id = static_cast<unsigned short>(I);
- }
- void setClangDecl(const clang::ValueDecl *VD) { Cvdecl = VD; }
- void setDefinition(SExpr *E);
+ /// Return the definition of the variable.
+ /// For let-vars, this is the setting expression.
+ /// For function and self parameters, it is the type of the variable.
+ SExpr *definition() { return Definition; }
+ const SExpr *definition() const { return Definition; }
+
+ void setName(StringRef S) { Name = S; }
void setKind(VariableKind K) { Flags = K; }
+ void setDefinition(SExpr *E) { Definition = E; }
+ void setClangDecl(const clang::ValueDecl *VD) { Cvdecl = VD; }
template <class V>
typename V::R_SExpr traverse(V &Vs, typename V::R_Ctx Ctx) {
@@ -418,17 +405,13 @@ private:
friend class Let;
StringRef Name; // The name of the variable.
- SExprRef Definition; // The TIL type or definition
+ SExpr* Definition; // The TIL type or definition
const clang::ValueDecl *Cvdecl; // The clang declaration for this variable.
-
- unsigned short BlockID;
- unsigned short Id;
- mutable unsigned NumUses;
};
-// Placeholder for an expression that has not yet been created.
-// Used to implement lazy copy and rewriting strategies.
+/// Placeholder for an expression that has not yet been created.
+/// Used to implement lazy copy and rewriting strategies.
class Future : public SExpr {
public:
static bool classof(const SExpr *E) { return E->opcode() == COP_Future; }
@@ -439,22 +422,14 @@ public:
FS_done
};
- Future() :
- SExpr(COP_Future), Status(FS_pending), Result(nullptr), Location(nullptr)
- {}
+ Future() : SExpr(COP_Future), Status(FS_pending), Result(nullptr) {}
+
private:
virtual ~Future() LLVM_DELETED_FUNCTION;
-public:
-
- // Registers the location in the AST where this future is stored.
- // Forcing the future will automatically update the AST.
- static inline void registerLocation(SExprRef *Member) {
- if (Future *F = dyn_cast_or_null<Future>(Member->get()))
- F->Location = Member;
- }
+public:
// A lazy rewriting strategy should subclass Future and override this method.
- virtual SExpr *create() { return nullptr; }
+ virtual SExpr *compute() { return nullptr; }
// Return the result of this future if it exists, otherwise return null.
SExpr *maybeGetResult() const {
@@ -465,8 +440,7 @@ public:
SExpr *result() {
switch (Status) {
case FS_pending:
- force();
- return Result;
+ return force();
case FS_evaluating:
return nullptr; // infinite loop; illegal recursion.
case FS_done:
@@ -488,81 +462,14 @@ public:
}
private:
- // Force the future.
- inline void force();
+ SExpr* force();
FutureStatus Status;
SExpr *Result;
- SExprRef *Location;
};
-inline void SExprRef::attach() {
- if (!Ptr)
- return;
-
- TIL_Opcode Op = Ptr->opcode();
- if (Op == COP_Variable) {
- cast<Variable>(Ptr)->attachVar();
- } else if (Op == COP_Future) {
- cast<Future>(Ptr)->registerLocation(this);
- }
-}
-
-inline void SExprRef::detach() {
- if (Ptr && Ptr->opcode() == COP_Variable) {
- cast<Variable>(Ptr)->detachVar();
- }
-}
-
-inline SExprRef::SExprRef(SExpr *P) : Ptr(P) {
- attach();
-}
-
-inline SExprRef::~SExprRef() {
- detach();
-}
-
-inline void SExprRef::reset(SExpr *P) {
- detach();
- Ptr = P;
- attach();
-}
-
-
-inline Variable::Variable(StringRef s, SExpr *D)
- : SExpr(COP_Variable), Name(s), Definition(D), Cvdecl(nullptr),
- BlockID(0), Id(0), NumUses(0) {
- Flags = VK_Let;
-}
-
-inline Variable::Variable(SExpr *D, const clang::ValueDecl *Cvd)
- : SExpr(COP_Variable), Name(Cvd ? Cvd->getName() : "_x"),
- Definition(D), Cvdecl(Cvd), BlockID(0), Id(0), NumUses(0) {
- Flags = VK_Let;
-}
-
-inline Variable::Variable(const Variable &Vd, SExpr *D) // rewrite constructor
- : SExpr(Vd), Name(Vd.Name), Definition(D), Cvdecl(Vd.Cvdecl),
- BlockID(0), Id(0), NumUses(0) {
- Flags = Vd.kind();
-}
-
-inline void Variable::setDefinition(SExpr *E) {
- Definition.reset(E);
-}
-
-void Future::force() {
- Status = FS_evaluating;
- SExpr *R = create();
- Result = R;
- if (Location)
- Location->reset(R);
- Status = FS_done;
-}
-
-
-// Placeholder for C++ expressions that cannot be represented in the TIL.
+/// Placeholder for expressions that cannot be represented in the TIL.
class Undefined : public SExpr {
public:
static bool classof(const SExpr *E) { return E->opcode() == COP_Undefined; }
@@ -585,7 +492,7 @@ private:
};
-// Placeholder for a wildcard that matches any other expression.
+/// Placeholder for a wildcard that matches any other expression.
class Wildcard : public SExpr {
public:
static bool classof(const SExpr *E) { return E->opcode() == COP_Wildcard; }
@@ -716,8 +623,8 @@ typename V::R_SExpr Literal::traverse(V
}
-// Literal pointer to an object allocated in memory.
-// At compile time, pointer literals are represented by symbolic names.
+/// A Literal pointer to an object allocated in memory.
+/// At compile time, pointer literals are represented by symbolic names.
class LiteralPtr : public SExpr {
public:
static bool classof(const SExpr *E) { return E->opcode() == COP_LiteralPtr; }
@@ -743,9 +650,9 @@ private:
};
-// A function -- a.k.a. lambda abstraction.
-// Functions with multiple arguments are created by currying,
-// e.g. (function (x: Int) (function (y: Int) (add x y)))
+/// A function -- a.k.a. lambda abstraction.
+/// Functions with multiple arguments are created by currying,
+/// e.g. (Function (x: Int) (Function (y: Int) (Code { return x + y })))
class Function : public SExpr {
public:
static bool classof(const SExpr *E) { return E->opcode() == COP_Function; }
@@ -762,8 +669,8 @@ public:
Variable *variableDecl() { return VarDecl; }
const Variable *variableDecl() const { return VarDecl; }
- SExpr *body() { return Body.get(); }
- const SExpr *body() const { return Body.get(); }
+ SExpr *body() { return Body; }
+ const SExpr *body() const { return Body; }
template <class V>
typename V::R_SExpr traverse(V &Vs, typename V::R_Ctx Ctx) {
@@ -790,13 +697,13 @@ public:
private:
Variable *VarDecl;
- SExprRef Body;
+ SExpr* Body;
};
-// A self-applicable function.
-// A self-applicable function can be applied to itself. It's useful for
-// implementing objects and late binding
+/// A self-applicable function.
+/// A self-applicable function can be applied to itself. It's useful for
+/// implementing objects and late binding.
class SFunction : public SExpr {
public:
static bool classof(const SExpr *E) { return E->opcode() == COP_SFunction; }
@@ -805,20 +712,20 @@ public:
: SExpr(COP_SFunction), VarDecl(Vd), Body(B) {
assert(Vd->Definition == nullptr);
Vd->setKind(Variable::VK_SFun);
- Vd->Definition.reset(this);
+ Vd->Definition = this;
}
SFunction(const SFunction &F, Variable *Vd, SExpr *B) // rewrite constructor
: SExpr(F), VarDecl(Vd), Body(B) {
assert(Vd->Definition == nullptr);
Vd->setKind(Variable::VK_SFun);
- Vd->Definition.reset(this);
+ Vd->Definition = this;
}
Variable *variableDecl() { return VarDecl; }
const Variable *variableDecl() const { return VarDecl; }
- SExpr *body() { return Body.get(); }
- const SExpr *body() const { return Body.get(); }
+ SExpr *body() { return Body; }
+ const SExpr *body() const { return Body; }
template <class V>
typename V::R_SExpr traverse(V &Vs, typename V::R_Ctx Ctx) {
@@ -842,11 +749,11 @@ public:
private:
Variable *VarDecl;
- SExprRef Body;
+ SExpr* Body;
};
-// A block of code -- e.g. the body of a function.
+/// A block of code -- e.g. the body of a function.
class Code : public SExpr {
public:
static bool classof(const SExpr *E) { return E->opcode() == COP_Code; }
@@ -855,11 +762,11 @@ public:
Code(const Code &C, SExpr *T, SExpr *B) // rewrite constructor
: SExpr(C), ReturnType(T), Body(B) {}
- SExpr *returnType() { return ReturnType.get(); }
- const SExpr *returnType() const { return ReturnType.get(); }
+ SExpr *returnType() { return ReturnType; }
+ const SExpr *returnType() const { return ReturnType; }
- SExpr *body() { return Body.get(); }
- const SExpr *body() const { return Body.get(); }
+ SExpr *body() { return Body; }
+ const SExpr *body() const { return Body; }
template <class V>
typename V::R_SExpr traverse(V &Vs, typename V::R_Ctx Ctx) {
@@ -877,12 +784,12 @@ public:
}
private:
- SExprRef ReturnType;
- SExprRef Body;
+ SExpr* ReturnType;
+ SExpr* Body;
};
-// A typed, writable location in memory
+/// A typed, writable location in memory
class Field : public SExpr {
public:
static bool classof(const SExpr *E) { return E->opcode() == COP_Field; }
@@ -891,11 +798,11 @@ public:
Field(const Field &C, SExpr *R, SExpr *B) // rewrite constructor
: SExpr(C), Range(R), Body(B) {}
- SExpr *range() { return Range.get(); }
- const SExpr *range() const { return Range.get(); }
+ SExpr *range() { return Range; }
+ const SExpr *range() const { return Range; }
- SExpr *body() { return Body.get(); }
- const SExpr *body() const { return Body.get(); }
+ SExpr *body() { return Body; }
+ const SExpr *body() const { return Body; }
template <class V>
typename V::R_SExpr traverse(V &Vs, typename V::R_Ctx Ctx) {
@@ -913,12 +820,16 @@ public:
}
private:
- SExprRef Range;
- SExprRef Body;
+ SExpr* Range;
+ SExpr* Body;
};
-// Apply an argument to a function
+/// Apply an argument to a function.
+/// Note that this does not actually call the function. Functions are curried,
+/// so this returns a closure in which the first parameter has been applied.
+/// Once all parameters have been applied, Call can be used to invoke the
+/// function.
class Apply : public SExpr {
public:
static bool classof(const SExpr *E) { return E->opcode() == COP_Apply; }
@@ -928,11 +839,11 @@ public:
: SExpr(A), Fun(F), Arg(Ar)
{}
- SExpr *fun() { return Fun.get(); }
- const SExpr *fun() const { return Fun.get(); }
+ SExpr *fun() { return Fun; }
+ const SExpr *fun() const { return Fun; }
- SExpr *arg() { return Arg.get(); }
- const SExpr *arg() const { return Arg.get(); }
+ SExpr *arg() { return Arg; }
+ const SExpr *arg() const { return Arg; }
template <class V>
typename V::R_SExpr traverse(V &Vs, typename V::R_Ctx Ctx) {
@@ -950,12 +861,12 @@ public:
}
private:
- SExprRef Fun;
- SExprRef Arg;
+ SExpr* Fun;
+ SExpr* Arg;
};
-// Apply a self-argument to a self-applicable function
+/// Apply a self-argument to a self-applicable function.
class SApply : public SExpr {
public:
static bool classof(const SExpr *E) { return E->opcode() == COP_SApply; }
@@ -964,18 +875,18 @@ public:
SApply(SApply &A, SExpr *Sf, SExpr *Ar = nullptr) // rewrite constructor
: SExpr(A), Sfun(Sf), Arg(Ar) {}
- SExpr *sfun() { return Sfun.get(); }
- const SExpr *sfun() const { return Sfun.get(); }
+ SExpr *sfun() { return Sfun; }
+ const SExpr *sfun() const { return Sfun; }
- SExpr *arg() { return Arg.get() ? Arg.get() : Sfun.get(); }
- const SExpr *arg() const { return Arg.get() ? Arg.get() : Sfun.get(); }
+ SExpr *arg() { return Arg ? Arg : Sfun; }
+ const SExpr *arg() const { return Arg ? Arg : Sfun; }
bool isDelegation() const { return Arg != nullptr; }
template <class V>
typename V::R_SExpr traverse(V &Vs, typename V::R_Ctx Ctx) {
auto Nf = Vs.traverse(Sfun, Vs.subExprCtx(Ctx));
- typename V::R_SExpr Na = Arg.get() ? Vs.traverse(Arg, Vs.subExprCtx(Ctx))
+ typename V::R_SExpr Na = Arg ? Vs.traverse(Arg, Vs.subExprCtx(Ctx))
: nullptr;
return Vs.reduceSApply(*this, Nf, Na);
}
@@ -989,12 +900,12 @@ public:
}
private:
- SExprRef Sfun;
- SExprRef Arg;
+ SExpr* Sfun;
+ SExpr* Arg;
};
-// Project a named slot from a C++ struct or class.
+/// Project a named slot from a C++ struct or class.
class Project : public SExpr {
public:
static bool classof(const SExpr *E) { return E->opcode() == COP_Project; }
@@ -1009,8 +920,8 @@ public:
: SExpr(P), Rec(R), SlotName(P.SlotName), Cvdecl(P.Cvdecl)
{ }
- SExpr *record() { return Rec.get(); }
- const SExpr *record() const { return Rec.get(); }
+ SExpr *record() { return Rec; }
+ const SExpr *record() const { return Rec; }
const clang::ValueDecl *clangDecl() const { return Cvdecl; }
@@ -1042,13 +953,13 @@ public:
}
private:
- SExprRef Rec;
+ SExpr* Rec;
StringRef SlotName;
const clang::ValueDecl *Cvdecl;
};
-// Call a function (after all arguments have been applied).
+/// Call a function (after all arguments have been applied).
class Call : public SExpr {
public:
static bool classof(const SExpr *E) { return E->opcode() == COP_Call; }
@@ -1057,8 +968,8 @@ public:
: SExpr(COP_Call), Target(T), Cexpr(Ce) {}
Call(const Call &C, SExpr *T) : SExpr(C), Target(T), Cexpr(C.Cexpr) {}
- SExpr *target() { return Target.get(); }
- const SExpr *target() const { return Target.get(); }
+ SExpr *target() { return Target; }
+ const SExpr *target() const { return Target; }
const clang::CallExpr *clangCallExpr() const { return Cexpr; }
@@ -1074,12 +985,12 @@ public:
}
private:
- SExprRef Target;
+ SExpr* Target;
const clang::CallExpr *Cexpr;
};
-// Allocate memory for a new value on the heap or stack.
+/// Allocate memory for a new value on the heap or stack.
class Alloc : public SExpr {
public:
static bool classof(const SExpr *E) { return E->opcode() == COP_Call; }
@@ -1094,8 +1005,8 @@ public:
AllocKind kind() const { return static_cast<AllocKind>(Flags); }
- SExpr *dataType() { return Dtype.get(); }
- const SExpr *dataType() const { return Dtype.get(); }
+ SExpr *dataType() { return Dtype; }
+ const SExpr *dataType() const { return Dtype; }
template <class V>
typename V::R_SExpr traverse(V &Vs, typename V::R_Ctx Ctx) {
@@ -1112,11 +1023,11 @@ public:
}
private:
- SExprRef Dtype;
+ SExpr* Dtype;
};
-// Load a value from memory.
+/// Load a value from memory.
class Load : public SExpr {
public:
static bool classof(const SExpr *E) { return E->opcode() == COP_Load; }
@@ -1124,8 +1035,8 @@ public:
Load(SExpr *P) : SExpr(COP_Load), Ptr(P) {}
Load(const Load &L, SExpr *P) : SExpr(L), Ptr(P) {}
- SExpr *pointer() { return Ptr.get(); }
- const SExpr *pointer() const { return Ptr.get(); }
+ SExpr *pointer() { return Ptr; }
+ const SExpr *pointer() const { return Ptr; }
template <class V>
typename V::R_SExpr traverse(V &Vs, typename V::R_Ctx Ctx) {
@@ -1139,12 +1050,12 @@ public:
}
private:
- SExprRef Ptr;
+ SExpr* Ptr;
};
-// Store a value to memory.
-// Source is a pointer, destination is the value to store.
+/// Store a value to memory.
+/// The destination is a pointer to a field, the source is the value to store.
class Store : public SExpr {
public:
static bool classof(const SExpr *E) { return E->opcode() == COP_Store; }
@@ -1152,11 +1063,11 @@ public:
Store(SExpr *P, SExpr *V) : SExpr(COP_Store), Dest(P), Source(V) {}
Store(const Store &S, SExpr *P, SExpr *V) : SExpr(S), Dest(P), Source(V) {}
- SExpr *destination() { return Dest.get(); } // Address to store to
- const SExpr *destination() const { return Dest.get(); }
+ SExpr *destination() { return Dest; } // Address to store to
+ const SExpr *destination() const { return Dest; }
- SExpr *source() { return Source.get(); } // Value to store
- const SExpr *source() const { return Source.get(); }
+ SExpr *source() { return Source; } // Value to store
+ const SExpr *source() const { return Source; }
template <class V>
typename V::R_SExpr traverse(V &Vs, typename V::R_Ctx Ctx) {
@@ -1174,13 +1085,13 @@ public:
}
private:
- SExprRef Dest;
- SExprRef Source;
+ SExpr* Dest;
+ SExpr* Source;
};
-// If p is a reference to an array, then first(p) is a reference to the first
-// element. The usual array notation p[i] becomes first(p + i).
+/// If p is a reference to an array, then p[i] is a reference to the i'th
+/// element of the array.
class ArrayIndex : public SExpr {
public:
static bool classof(const SExpr *E) { return E->opcode() == COP_ArrayIndex; }
@@ -1189,11 +1100,11 @@ public:
ArrayIndex(const ArrayIndex &E, SExpr *A, SExpr *N)
: SExpr(E), Array(A), Index(N) {}
- SExpr *array() { return Array.get(); }
- const SExpr *array() const { return Array.get(); }
+ SExpr *array() { return Array; }
+ const SExpr *array() const { return Array; }
- SExpr *index() { return Index.get(); }
- const SExpr *index() const { return Index.get(); }
+ SExpr *index() { return Index; }
+ const SExpr *index() const { return Index; }
template <class V>
typename V::R_SExpr traverse(V &Vs, typename V::R_Ctx Ctx) {
@@ -1211,14 +1122,14 @@ public:
}
private:
- SExprRef Array;
- SExprRef Index;
+ SExpr* Array;
+ SExpr* Index;
};
-// Pointer arithmetic, restricted to arrays only.
-// If p is a reference to an array, then p + n, where n is an integer, is
-// a reference to a subarray.
+/// Pointer arithmetic, restricted to arrays only.
+/// If p is a reference to an array, then p + n, where n is an integer, is
+/// a reference to a subarray.
class ArrayAdd : public SExpr {
public:
static bool classof(const SExpr *E) { return E->opcode() == COP_ArrayAdd; }
@@ -1227,11 +1138,11 @@ public:
ArrayAdd(const ArrayAdd &E, SExpr *A, SExpr *N)
: SExpr(E), Array(A), Index(N) {}
- SExpr *array() { return Array.get(); }
- const SExpr *array() const { return Array.get(); }
+ SExpr *array() { return Array; }
+ const SExpr *array() const { return Array; }
- SExpr *index() { return Index.get(); }
- const SExpr *index() const { return Index.get(); }
+ SExpr *index() { return Index; }
+ const SExpr *index() const { return Index; }
template <class V>
typename V::R_SExpr traverse(V &Vs, typename V::R_Ctx Ctx) {
@@ -1249,12 +1160,13 @@ public:
}
private:
- SExprRef Array;
- SExprRef Index;
+ SExpr* Array;
+ SExpr* Index;
};
-// Simple unary operation -- e.g. !, ~, etc.
+/// Simple arithmetic unary operations, e.g. negate and not.
+/// These operations have no side-effects.
class UnaryOp : public SExpr {
public:
static bool classof(const SExpr *E) { return E->opcode() == COP_UnaryOp; }
@@ -1268,8 +1180,8 @@ public:
return static_cast<TIL_UnaryOpcode>(Flags);
}
- SExpr *expr() { return Expr0.get(); }
- const SExpr *expr() const { return Expr0.get(); }
+ SExpr *expr() { return Expr0; }
+ const SExpr *expr() const { return Expr0; }
template <class V>
typename V::R_SExpr traverse(V &Vs, typename V::R_Ctx Ctx) {
@@ -1287,11 +1199,12 @@ public:
}
private:
- SExprRef Expr0;
+ SExpr* Expr0;
};
-// Simple binary operation -- e.g. +, -, etc.
+/// Simple arithmetic binary operations, e.g. +, -, etc.
+/// These operations have no side effects.
class BinaryOp : public SExpr {
public:
static bool classof(const SExpr *E) { return E->opcode() == COP_BinaryOp; }
@@ -1309,11 +1222,11 @@ public:
return static_cast<TIL_BinaryOpcode>(Flags);
}
- SExpr *expr0() { return Expr0.get(); }
- const SExpr *expr0() const { return Expr0.get(); }
+ SExpr *expr0() { return Expr0; }
+ const SExpr *expr0() const { return Expr0; }
- SExpr *expr1() { return Expr1.get(); }
- const SExpr *expr1() const { return Expr1.get(); }
+ SExpr *expr1() { return Expr1; }
+ const SExpr *expr1() const { return Expr1; }
template <class V>
typename V::R_SExpr traverse(V &Vs, typename V::R_Ctx Ctx) {
@@ -1335,12 +1248,14 @@ public:
}
private:
- SExprRef Expr0;
- SExprRef Expr1;
+ SExpr* Expr0;
+ SExpr* Expr1;
};
-// Cast expression
+/// Cast expressions.
+/// Cast expressions are essentially unary operations, but we treat them
+/// as a distinct AST node because they only change the type of the result.
class Cast : public SExpr {
public:
static bool classof(const SExpr *E) { return E->opcode() == COP_Cast; }
@@ -1352,8 +1267,8 @@ public:
return static_cast<TIL_CastOpcode>(Flags);
}
- SExpr *expr() { return Expr0.get(); }
- const SExpr *expr() const { return Expr0.get(); }
+ SExpr *expr() { return Expr0; }
+ const SExpr *expr() const { return Expr0; }
template <class V>
typename V::R_SExpr traverse(V &Vs, typename V::R_Ctx Ctx) {
@@ -1371,16 +1286,18 @@ public:
}
private:
- SExprRef Expr0;
+ SExpr* Expr0;
};
class SCFG;
+/// Phi Node, for code in SSA form.
+/// Each Phi node has an array of possible values that it can take,
+/// depending on where control flow comes from.
class Phi : public SExpr {
public:
- // TODO: change to SExprRef
typedef SimpleArray<SExpr *> ValArray;
// In minimal SSA form, all Phi nodes are MultiVal.
@@ -1394,9 +1311,12 @@ public:
static bool classof(const SExpr *E) { return E->opcode() == COP_Phi; }
- Phi() : SExpr(COP_Phi) {}
- Phi(MemRegionRef A, unsigned Nvals) : SExpr(COP_Phi), Values(A, Nvals) {}
- Phi(const Phi &P, ValArray &&Vs) : SExpr(P), Values(std::move(Vs)) {}
+ Phi()
+ : SExpr(COP_Phi), Cvdecl(nullptr) {}
+ Phi(MemRegionRef A, unsigned Nvals)
+ : SExpr(COP_Phi), Values(A, Nvals), Cvdecl(nullptr) {}
+ Phi(const Phi &P, ValArray &&Vs)
+ : SExpr(P), Values(std::move(Vs)), Cvdecl(nullptr) {}
const ValArray &values() const { return Values; }
ValArray &values() { return Values; }
@@ -1404,6 +1324,12 @@ public:
Status status() const { return static_cast<Status>(Flags); }
void setStatus(Status s) { Flags = s; }
+ /// Return the clang declaration of the variable for this Phi node, if any.
+ const clang::ValueDecl *clangDecl() const { return Cvdecl; }
+
+ /// Set the clang variable associated with this Phi node.
+ void setClangDecl(const clang::ValueDecl *Cvd) { Cvdecl = Cvd; }
+
template <class V>
typename V::R_SExpr traverse(V &Vs, typename V::R_Ctx Ctx) {
typename V::template Container<typename V::R_SExpr>
@@ -1423,65 +1349,260 @@ public:
private:
ValArray Values;
+ const clang::ValueDecl* Cvdecl;
+};
+
+
+/// Base class for basic block terminators: Branch, Goto, and Return.
+class Terminator : public SExpr {
+public:
+ static bool classof(const SExpr *E) {
+ return E->opcode() >= COP_Goto && E->opcode() <= COP_Return;
+ }
+
+protected:
+ Terminator(TIL_Opcode Op) : SExpr(Op) {}
+ Terminator(const SExpr &E) : SExpr(E) {}
+
+public:
+ /// Return the list of basic blocks that this terminator can branch to.
+ ArrayRef<BasicBlock*> successors();
+
+ ArrayRef<BasicBlock*> successors() const {
+ return const_cast<const Terminator*>(this)->successors();
+ }
+};
+
+
+/// Jump to another basic block.
+/// A goto instruction is essentially a tail-recursive call into another
+/// block. In addition to the block pointer, it specifies an index into the
+/// phi nodes of that block. The index can be used to retrieve the "arguments"
+/// of the call.
+class Goto : public Terminator {
+public:
+ static bool classof(const SExpr *E) { return E->opcode() == COP_Goto; }
+
+ Goto(BasicBlock *B, unsigned I)
+ : Terminator(COP_Goto), TargetBlock(B), Index(I) {}
+ Goto(const Goto &G, BasicBlock *B, unsigned I)
+ : Terminator(COP_Goto), TargetBlock(B), Index(I) {}
+
+ const BasicBlock *targetBlock() const { return TargetBlock; }
+ BasicBlock *targetBlock() { return TargetBlock; }
+
+ /// Returns the index into the
+ unsigned index() const { return Index; }
+
+ /// Return the list of basic blocks that this terminator can branch to.
+ ArrayRef<BasicBlock*> successors() {
+ return ArrayRef<BasicBlock*>(&TargetBlock, 1);
+ }
+
+ template <class V>
+ typename V::R_SExpr traverse(V &Vs, typename V::R_Ctx Ctx) {
+ BasicBlock *Ntb = Vs.reduceBasicBlockRef(TargetBlock);
+ return Vs.reduceGoto(*this, Ntb);
+ }
+
+ template <class C>
+ typename C::CType compare(const Goto *E, C &Cmp) const {
+ // TODO: implement CFG comparisons
+ return Cmp.comparePointers(this, E);
+ }
+
+private:
+ BasicBlock *TargetBlock;
+ unsigned Index;
+};
+
+
+/// A conditional branch to two other blocks.
+/// Note that unlike Goto, Branch does not have an index. The target blocks
+/// must be child-blocks, and cannot have Phi nodes.
+class Branch : public Terminator {
+public:
+ static bool classof(const SExpr *E) { return E->opcode() == COP_Branch; }
+
+ Branch(SExpr *C, BasicBlock *T, BasicBlock *E)
+ : Terminator(COP_Branch), Condition(C) {
+ Branches[0] = T;
+ Branches[1] = E;
+ }
+ Branch(const Branch &Br, SExpr *C, BasicBlock *T, BasicBlock *E)
+ : Terminator(Br), Condition(C) {
+ Branches[0] = T;
+ Branches[1] = E;
+ }
+
+ const SExpr *condition() const { return Condition; }
+ SExpr *condition() { return Condition; }
+
+ const BasicBlock *thenBlock() const { return Branches[0]; }
+ BasicBlock *thenBlock() { return Branches[0]; }
+
+ const BasicBlock *elseBlock() const { return Branches[1]; }
+ BasicBlock *elseBlock() { return Branches[1]; }
+
+ /// Return the list of basic blocks that this terminator can branch to.
+ ArrayRef<BasicBlock*> successors() {
+ return ArrayRef<BasicBlock*>(Branches, 2);
+ }
+
+ template <class V>
+ typename V::R_SExpr traverse(V &Vs, typename V::R_Ctx Ctx) {
+ auto Nc = Vs.traverse(Condition, Vs.subExprCtx(Ctx));
+ BasicBlock *Ntb = Vs.reduceBasicBlockRef(Branches[0]);
+ BasicBlock *Nte = Vs.reduceBasicBlockRef(Branches[1]);
+ return Vs.reduceBranch(*this, Nc, Ntb, Nte);
+ }
+
+ template <class C>
+ typename C::CType compare(const Branch *E, C &Cmp) const {
+ // TODO: implement CFG comparisons
+ return Cmp.comparePointers(this, E);
+ }
+
+private:
+ SExpr* Condition;
+ BasicBlock *Branches[2];
+};
+
+
+/// Return from the enclosing function, passing the return value to the caller.
+/// Only the exit block should end with a return statement.
+class Return : public Terminator {
+public:
+ static bool classof(const SExpr *E) { return E->opcode() == COP_Return; }
+
+ Return(SExpr* Rval) : Terminator(COP_Return), Retval(Rval) {}
+ Return(const Return &R, SExpr* Rval) : Terminator(R), Retval(Rval) {}
+
+ /// Return an empty list.
+ ArrayRef<BasicBlock*> successors() {
+ return ArrayRef<BasicBlock*>();
+ }
+
+ SExpr *returnValue() { return Retval; }
+ const SExpr *returnValue() const { return Retval; }
+
+ template <class V>
+ typename V::R_SExpr traverse(V &Vs, typename V::R_Ctx Ctx) {
+ auto Ne = Vs.traverse(Retval, Vs.subExprCtx(Ctx));
+ return Vs.reduceReturn(*this, Ne);
+ }
+
+ template <class C>
+ typename C::CType compare(const Return *E, C &Cmp) const {
+ return Cmp.compare(Retval, E->Retval);
+ }
+
+private:
+ SExpr* Retval;
};
-// A basic block is part of an SCFG, and can be treated as a function in
-// continuation passing style. It consists of a sequence of phi nodes, which
-// are "arguments" to the function, followed by a sequence of instructions.
-// Both arguments and instructions define new variables. It ends with a
-// branch or goto to another basic block in the same SCFG.
+inline ArrayRef<BasicBlock*> Terminator::successors() {
+ switch (opcode()) {
+ case COP_Goto: return cast<Goto>(this)->successors();
+ case COP_Branch: return cast<Branch>(this)->successors();
+ case COP_Return: return cast<Return>(this)->successors();
+ default:
+ return ArrayRef<BasicBlock*>();
+ }
+}
+
+
+/// A basic block is part of an SCFG. It can be treated as a function in
+/// continuation passing style. A block consists of a sequence of phi nodes,
+/// which are "arguments" to the function, followed by a sequence of
+/// instructions. It ends with a Terminator, which is a Branch or Goto to
+/// another basic block in the same SCFG.
class BasicBlock : public SExpr {
public:
- typedef SimpleArray<Variable*> VarArray;
+ typedef SimpleArray<SExpr*> InstrArray;
typedef SimpleArray<BasicBlock*> BlockArray;
+ // TopologyNodes are used to overlay tree structures on top of the CFG,
+ // such as dominator and postdominator trees. Each block is assigned an
+ // ID in the tree according to a depth-first search. Tree traversals are
+ // always up, towards the parents.
+ struct TopologyNode {
+ TopologyNode() : NodeID(0), SizeOfSubTree(0), Parent(nullptr) {}
+
+ bool isParentOf(const TopologyNode& OtherNode) {
+ return OtherNode.NodeID > NodeID &&
+ OtherNode.NodeID < NodeID + SizeOfSubTree;
+ }
+
+ bool isParentOfOrEqual(const TopologyNode& OtherNode) {
+ return OtherNode.NodeID >= NodeID &&
+ OtherNode.NodeID < NodeID + SizeOfSubTree;
+ }
+
+ int NodeID;
+ int SizeOfSubTree; // Includes this node, so must be > 1.
+ BasicBlock *Parent; // Pointer to parent.
+ };
+
static bool classof(const SExpr *E) { return E->opcode() == COP_BasicBlock; }
- explicit BasicBlock(MemRegionRef A, BasicBlock* P = nullptr)
+ explicit BasicBlock(MemRegionRef A)
: SExpr(COP_BasicBlock), Arena(A), CFGPtr(nullptr), BlockID(0),
- Parent(P), Terminator(nullptr)
- { }
- BasicBlock(BasicBlock &B, VarArray &&As, VarArray &&Is, SExpr *T)
- : SExpr(COP_BasicBlock), Arena(B.Arena), CFGPtr(nullptr), BlockID(0),
- Parent(nullptr), Args(std::move(As)), Instrs(std::move(Is)),
- Terminator(T)
- { }
-
- unsigned blockID() const { return BlockID; }
- unsigned numPredecessors() const { return Predecessors.size(); }
+ Visited(0), TermInstr(nullptr) {}
+ BasicBlock(BasicBlock &B, MemRegionRef A, InstrArray &&As, InstrArray &&Is,
+ Terminator *T)
+ : SExpr(COP_BasicBlock), Arena(A), CFGPtr(nullptr), BlockID(0),Visited(0),
+ Args(std::move(As)), Instrs(std::move(Is)), TermInstr(T) {}
+
+ /// Returns the block ID. Every block has a unique ID in the CFG.
+ int blockID() const { return BlockID; }
+
+ /// Returns the number of predecessors.
+ size_t numPredecessors() const { return Predecessors.size(); }
+ size_t numSuccessors() const { return successors().size(); }
const SCFG* cfg() const { return CFGPtr; }
SCFG* cfg() { return CFGPtr; }
- const BasicBlock *parent() const { return Parent; }
- BasicBlock *parent() { return Parent; }
+ const BasicBlock *parent() const { return DominatorNode.Parent; }
+ BasicBlock *parent() { return DominatorNode.Parent; }
- const VarArray &arguments() const { return Args; }
- VarArray &arguments() { return Args; }
+ const InstrArray &arguments() const { return Args; }
+ InstrArray &arguments() { return Args; }
- const VarArray &instructions() const { return Instrs; }
- VarArray &instructions() { return Instrs; }
+ InstrArray &instructions() { return Instrs; }
+ const InstrArray &instructions() const { return Instrs; }
- const BlockArray &predecessors() const { return Predecessors; }
+ /// Returns a list of predecessors.
+ /// The order of predecessors in the list is important; each phi node has
+ /// exactly one argument for each precessor, in the same order.
BlockArray &predecessors() { return Predecessors; }
+ const BlockArray &predecessors() const { return Predecessors; }
+
+ ArrayRef<BasicBlock*> successors() { return TermInstr->successors(); }
+ ArrayRef<BasicBlock*> successors() const { return TermInstr->successors(); }
- const SExpr *terminator() const { return Terminator.get(); }
- SExpr *terminator() { return Terminator.get(); }
+ const Terminator *terminator() const { return TermInstr; }
+ Terminator *terminator() { return TermInstr; }
- void setBlockID(unsigned i) { BlockID = i; }
- void setParent(BasicBlock *P) { Parent = P; }
- void setTerminator(SExpr *E) { Terminator.reset(E); }
-
- // Add a new argument. V must define a phi-node.
- void addArgument(Variable *V) {
- V->setKind(Variable::VK_LetBB);
+ void setTerminator(Terminator *E) { TermInstr = E; }
+
+ bool Dominates(const BasicBlock &Other) {
+ return DominatorNode.isParentOfOrEqual(Other.DominatorNode);
+ }
+
+ bool PostDominates(const BasicBlock &Other) {
+ return PostDominatorNode.isParentOfOrEqual(Other.PostDominatorNode);
+ }
+
+ /// Add a new argument.
+ void addArgument(Phi *V) {
Args.reserveCheck(1, Arena);
Args.push_back(V);
}
- // Add a new instruction.
- void addInstruction(Variable *V) {
- V->setKind(Variable::VK_LetBB);
+ /// Add a new instruction.
+ void addInstruction(SExpr *V) {
Instrs.reserveCheck(1, Arena);
Instrs.push_back(V);
}
@@ -1498,34 +1619,29 @@ public:
// Reserve space for NumPreds predecessors, including space in phi nodes.
void reservePredecessors(unsigned NumPreds);
- // Return the index of BB, or Predecessors.size if BB is not a predecessor.
+ /// Return the index of BB, or Predecessors.size if BB is not a predecessor.
unsigned findPredecessorIndex(const BasicBlock *BB) const {
auto I = std::find(Predecessors.cbegin(), Predecessors.cend(), BB);
return std::distance(Predecessors.cbegin(), I);
}
- // Set id numbers for variables.
- void renumberVars();
-
template <class V>
typename V::R_BasicBlock traverse(V &Vs, typename V::R_Ctx Ctx) {
- typename V::template Container<Variable*> Nas(Vs, Args.size());
- typename V::template Container<Variable*> Nis(Vs, Instrs.size());
+ typename V::template Container<SExpr*> Nas(Vs, Args.size());
+ typename V::template Container<SExpr*> Nis(Vs, Instrs.size());
// Entering the basic block should do any scope initialization.
Vs.enterBasicBlock(*this);
- for (auto *A : Args) {
- auto Ne = Vs.traverse(A->Definition, Vs.subExprCtx(Ctx));
- Variable *Nvd = Vs.enterScope(*A, Ne);
- Nas.push_back(Nvd);
+ for (auto *E : Args) {
+ auto Ne = Vs.traverse(E, Vs.subExprCtx(Ctx));
+ Nas.push_back(Ne);
}
- for (auto *I : Instrs) {
- auto Ne = Vs.traverse(I->Definition, Vs.subExprCtx(Ctx));
- Variable *Nvd = Vs.enterScope(*I, Ne);
- Nis.push_back(Nvd);
+ for (auto *E : Instrs) {
+ auto Ne = Vs.traverse(E, Vs.subExprCtx(Ctx));
+ Nis.push_back(Ne);
}
- auto Nt = Vs.traverse(Terminator, Ctx);
+ auto Nt = Vs.traverse(TermInstr, Ctx);
// Exiting the basic block should handle any scope cleanup.
Vs.exitBasicBlock(*this);
@@ -1542,22 +1658,32 @@ public:
private:
friend class SCFG;
- MemRegionRef Arena;
-
- SCFG *CFGPtr; // The CFG that contains this block.
- unsigned BlockID; // unique id for this BB in the containing CFG
- BasicBlock *Parent; // The parent block is the enclosing lexical scope.
- // The parent dominates this block.
- BlockArray Predecessors; // Predecessor blocks in the CFG.
- VarArray Args; // Phi nodes. One argument per predecessor.
- VarArray Instrs; // Instructions.
- SExprRef Terminator; // Branch or Goto
+ int renumberInstrs(int id); // assign unique ids to all instructions
+ int topologicalSort(SimpleArray<BasicBlock*>& Blocks, int ID);
+ int topologicalFinalSort(SimpleArray<BasicBlock*>& Blocks, int ID);
+ void computeDominator();
+ void computePostDominator();
+
+private:
+ MemRegionRef Arena; // The arena used to allocate this block.
+ SCFG *CFGPtr; // The CFG that contains this block.
+ int BlockID : 31; // unique id for this BB in the containing CFG.
+ // IDs are in topological order.
+ int Visited : 1; // Bit to determine if a block has been visited
+ // during a traversal.
+ BlockArray Predecessors; // Predecessor blocks in the CFG.
+ InstrArray Args; // Phi nodes. One argument per predecessor.
+ InstrArray Instrs; // Instructions.
+ Terminator* TermInstr; // Terminating instruction
+
+ TopologyNode DominatorNode; // The dominator tree
+ TopologyNode PostDominatorNode; // The post-dominator tree
};
-// An SCFG is a control-flow graph. It consists of a set of basic blocks, each
-// of which terminates in a branch to another basic block. There is one
-// entry point, and one exit point.
+/// An SCFG is a control-flow graph. It consists of a set of basic blocks,
+/// each of which terminates in a branch to another basic block. There is one
+/// entry point, and one exit point.
class SCFG : public SExpr {
public:
typedef SimpleArray<BasicBlock *> BlockArray;
@@ -1568,20 +1694,29 @@ public:
SCFG(MemRegionRef A, unsigned Nblocks)
: SExpr(COP_SCFG), Arena(A), Blocks(A, Nblocks),
- Entry(nullptr), Exit(nullptr) {
- Entry = new (A) BasicBlock(A, nullptr);
- Exit = new (A) BasicBlock(A, Entry);
- auto *V = new (A) Variable(new (A) Phi());
+ Entry(nullptr), Exit(nullptr), NumInstructions(0), Normal(false) {
+ Entry = new (A) BasicBlock(A);
+ Exit = new (A) BasicBlock(A);
+ auto *V = new (A) Phi();
Exit->addArgument(V);
+ Exit->setTerminator(new (A) Return(V));
add(Entry);
add(Exit);
}
SCFG(const SCFG &Cfg, BlockArray &&Ba) // steals memory from Ba
: SExpr(COP_SCFG), Arena(Cfg.Arena), Blocks(std::move(Ba)),
- Entry(nullptr), Exit(nullptr) {
+ Entry(nullptr), Exit(nullptr), NumInstructions(0), Normal(false) {
// TODO: set entry and exit!
}
+ /// Return true if this CFG is valid.
+ bool valid() const { return Entry && Exit && Blocks.size() > 0; }
+
+ /// Return true if this CFG has been normalized.
+ /// After normalization, blocks are in topological order, and block and
+ /// instruction IDs have been assigned.
+ bool normal() const { return Normal; }
+
iterator begin() { return Blocks.begin(); }
iterator end() { return Blocks.end(); }
@@ -1596,9 +1731,17 @@ public:
const BasicBlock *exit() const { return Exit; }
BasicBlock *exit() { return Exit; }
+ /// Return the number of blocks in the CFG.
+ /// Block::blockID() will return a number less than numBlocks();
+ size_t numBlocks() const { return Blocks.size(); }
+
+ /// Return the total number of instructions in the CFG.
+ /// This is useful for building instruction side-tables;
+ /// A call to SExpr::id() will return a number less than numInstructions().
+ unsigned numInstructions() { return NumInstructions; }
+
inline void add(BasicBlock *BB) {
- assert(BB->CFGPtr == nullptr || BB->CFGPtr == this);
- BB->setBlockID(Blocks.size());
+ assert(BB->CFGPtr == nullptr);
BB->CFGPtr = this;
Blocks.reserveCheck(1, Arena);
Blocks.push_back(BB);
@@ -1607,13 +1750,13 @@ public:
void setEntry(BasicBlock *BB) { Entry = BB; }
void setExit(BasicBlock *BB) { Exit = BB; }
- // Set varable ids in all blocks.
- void renumberVars();
+ void computeNormalForm();
template <class V>
typename V::R_SExpr traverse(V &Vs, typename V::R_Ctx Ctx) {
Vs.enterCFG(*this);
typename V::template Container<BasicBlock *> Bbs(Vs, Blocks.size());
+
for (auto *B : Blocks) {
Bbs.push_back( B->traverse(Vs, Vs.subExprCtx(Ctx)) );
}
@@ -1623,101 +1766,26 @@ public:
template <class C>
typename C::CType compare(const SCFG *E, C &Cmp) const {
- // TODO -- implement CFG comparisons
+ // TODO: implement CFG comparisons
return Cmp.comparePointers(this, E);
}
private:
+ void renumberInstrs(); // assign unique ids to all instructions
+
+private:
MemRegionRef Arena;
BlockArray Blocks;
BasicBlock *Entry;
BasicBlock *Exit;
+ unsigned NumInstructions;
+ bool Normal;
};
-class Goto : public SExpr {
-public:
- static bool classof(const SExpr *E) { return E->opcode() == COP_Goto; }
-
- Goto(BasicBlock *B, unsigned I)
- : SExpr(COP_Goto), TargetBlock(B), Index(I) {}
- Goto(const Goto &G, BasicBlock *B, unsigned I)
- : SExpr(COP_Goto), TargetBlock(B), Index(I) {}
-
- const BasicBlock *targetBlock() const { return TargetBlock; }
- BasicBlock *targetBlock() { return TargetBlock; }
-
- unsigned index() const { return Index; }
-
- template <class V>
- typename V::R_SExpr traverse(V &Vs, typename V::R_Ctx Ctx) {
- BasicBlock *Ntb = Vs.reduceBasicBlockRef(TargetBlock);
- return Vs.reduceGoto(*this, Ntb);
- }
-
- template <class C>
- typename C::CType compare(const Goto *E, C &Cmp) const {
- // TODO -- implement CFG comparisons
- return Cmp.comparePointers(this, E);
- }
-
-private:
- BasicBlock *TargetBlock;
- unsigned Index; // Index into Phi nodes of target block.
-};
-
-
-class Branch : public SExpr {
-public:
- static bool classof(const SExpr *E) { return E->opcode() == COP_Branch; }
-
- Branch(SExpr *C, BasicBlock *T, BasicBlock *E, unsigned TI, unsigned EI)
- : SExpr(COP_Branch), Condition(C), ThenBlock(T), ElseBlock(E),
- ThenIndex(TI), ElseIndex(EI)
- {}
- Branch(const Branch &Br, SExpr *C, BasicBlock *T, BasicBlock *E,
- unsigned TI, unsigned EI)
- : SExpr(COP_Branch), Condition(C), ThenBlock(T), ElseBlock(E),
- ThenIndex(TI), ElseIndex(EI)
- {}
-
- const SExpr *condition() const { return Condition; }
- SExpr *condition() { return Condition; }
-
- const BasicBlock *thenBlock() const { return ThenBlock; }
- BasicBlock *thenBlock() { return ThenBlock; }
-
- const BasicBlock *elseBlock() const { return ElseBlock; }
- BasicBlock *elseBlock() { return ElseBlock; }
-
- unsigned thenIndex() const { return ThenIndex; }
- unsigned elseIndex() const { return ElseIndex; }
-
- template <class V>
- typename V::R_SExpr traverse(V &Vs, typename V::R_Ctx Ctx) {
- auto Nc = Vs.traverse(Condition, Vs.subExprCtx(Ctx));
- BasicBlock *Ntb = Vs.reduceBasicBlockRef(ThenBlock);
- BasicBlock *Nte = Vs.reduceBasicBlockRef(ElseBlock);
- return Vs.reduceBranch(*this, Nc, Ntb, Nte);
- }
- template <class C>
- typename C::CType compare(const Branch *E, C &Cmp) const {
- // TODO -- implement CFG comparisons
- return Cmp.comparePointers(this, E);
- }
-
-private:
- SExpr *Condition;
- BasicBlock *ThenBlock;
- BasicBlock *ElseBlock;
- unsigned ThenIndex;
- unsigned ElseIndex;
-};
-
-
-// An identifier, e.g. 'foo' or 'x'.
-// This is a pseduo-term; it will be lowered to a variable or projection.
+/// An identifier, e.g. 'foo' or 'x'.
+/// This is a pseduo-term; it will be lowered to a variable or projection.
class Identifier : public SExpr {
public:
static bool classof(const SExpr *E) { return E->opcode() == COP_Identifier; }
@@ -1742,8 +1810,8 @@ private:
};
-// An if-then-else expression.
-// This is a pseduo-term; it will be lowered to a branch in a CFG.
+/// An if-then-else expression.
+/// This is a pseduo-term; it will be lowered to a branch in a CFG.
class IfThenElse : public SExpr {
public:
static bool classof(const SExpr *E) { return E->opcode() == COP_IfThenElse; }
@@ -1755,14 +1823,14 @@ public:
: SExpr(I), Condition(C), ThenExpr(T), ElseExpr(E)
{ }
- SExpr *condition() { return Condition.get(); } // Address to store to
- const SExpr *condition() const { return Condition.get(); }
+ SExpr *condition() { return Condition; } // Address to store to
+ const SExpr *condition() const { return Condition; }
- SExpr *thenExpr() { return ThenExpr.get(); } // Value to store
- const SExpr *thenExpr() const { return ThenExpr.get(); }
+ SExpr *thenExpr() { return ThenExpr; } // Value to store
+ const SExpr *thenExpr() const { return ThenExpr; }
- SExpr *elseExpr() { return ElseExpr.get(); } // Value to store
- const SExpr *elseExpr() const { return ElseExpr.get(); }
+ SExpr *elseExpr() { return ElseExpr; } // Value to store
+ const SExpr *elseExpr() const { return ElseExpr; }
template <class V>
typename V::R_SExpr traverse(V &Vs, typename V::R_Ctx Ctx) {
@@ -1784,14 +1852,14 @@ public:
}
private:
- SExprRef Condition;
- SExprRef ThenExpr;
- SExprRef ElseExpr;
+ SExpr* Condition;
+ SExpr* ThenExpr;
+ SExpr* ElseExpr;
};
-// A let-expression, e.g. let x=t; u.
-// This is a pseduo-term; it will be lowered to instructions in a CFG.
+/// A let-expression, e.g. let x=t; u.
+/// This is a pseduo-term; it will be lowered to instructions in a CFG.
class Let : public SExpr {
public:
static bool classof(const SExpr *E) { return E->opcode() == COP_Let; }
@@ -1806,8 +1874,8 @@ public:
Variable *variableDecl() { return VarDecl; }
const Variable *variableDecl() const { return VarDecl; }
- SExpr *body() { return Body.get(); }
- const SExpr *body() const { return Body.get(); }
+ SExpr *body() { return Body; }
+ const SExpr *body() const { return Body; }
template <class V>
typename V::R_SExpr traverse(V &Vs, typename V::R_Ctx Ctx) {
@@ -1834,14 +1902,14 @@ public:
private:
Variable *VarDecl;
- SExprRef Body;
+ SExpr* Body;
};
const SExpr *getCanonicalVal(const SExpr *E);
SExpr* simplifyToCanonicalVal(SExpr *E);
-void simplifyIncompleteArg(Variable *V, til::Phi *Ph);
+void simplifyIncompleteArg(til::Phi *Ph);
} // end namespace til
Modified: cfe/trunk/include/clang/Analysis/Analyses/ThreadSafetyTraverse.h
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/include/clang/Analysis/Analyses/ThreadSafetyTraverse.h?rev=217556&r1=217555&r2=217556&view=diff
==============================================================================
--- cfe/trunk/include/clang/Analysis/Analyses/ThreadSafetyTraverse.h (original)
+++ cfe/trunk/include/clang/Analysis/Analyses/ThreadSafetyTraverse.h Wed Sep 10 17:12:52 2014
@@ -58,11 +58,16 @@ public:
// Traverse an expression -- returning a result of type R_SExpr.
// Override this method to do something for every expression, regardless
// of which kind it is.
- typename R::R_SExpr traverse(SExprRef &E, typename R::R_Ctx Ctx) {
- return traverse(E.get(), Ctx);
+ // E is a reference, so this can be use for in-place updates.
+ // The type T must be a subclass of SExpr.
+ template <class T>
+ typename R::R_SExpr traverse(T* &E, typename R::R_Ctx Ctx) {
+ return traverseSExpr(E, Ctx);
}
- typename R::R_SExpr traverse(SExpr *E, typename R::R_Ctx Ctx) {
+ // Override this method to do something for every expression.
+ // Does not allow in-place updates.
+ typename R::R_SExpr traverseSExpr(SExpr *E, typename R::R_Ctx Ctx) {
return traverseByCase(E, Ctx);
}
@@ -75,6 +80,7 @@ public:
#include "ThreadSafetyOps.def"
#undef TIL_OPCODE_DEF
}
+ return self()->reduceNull();
}
// Traverse e, by static dispatch on the type "X" of e.
@@ -92,10 +98,10 @@ public:
class SimpleReducerBase {
public:
enum TraversalKind {
- TRV_Normal,
- TRV_Decl,
- TRV_Lazy,
- TRV_Type
+ TRV_Normal, // ordinary subexpressions
+ TRV_Decl, // declarations (e.g. function bodies)
+ TRV_Lazy, // expressions that require lazy evaluation
+ TRV_Type // type expressions
};
// R_Ctx defines a "context" for the traversal, which encodes information
@@ -147,153 +153,6 @@ protected:
};
-// Implements a traversal that makes a deep copy of an SExpr.
-// The default behavior of reduce##X(...) is to create a copy of the original.
-// Subclasses can override reduce##X to implement non-destructive rewriting
-// passes.
-template<class Self>
-class CopyReducer : public Traversal<Self, CopyReducerBase>,
- public CopyReducerBase {
-public:
- CopyReducer(MemRegionRef A) : CopyReducerBase(A) {}
-
-public:
- R_SExpr reduceNull() {
- return nullptr;
- }
- // R_SExpr reduceFuture(...) is never used.
-
- R_SExpr reduceUndefined(Undefined &Orig) {
- return new (Arena) Undefined(Orig);
- }
- R_SExpr reduceWildcard(Wildcard &Orig) {
- return new (Arena) Wildcard(Orig);
- }
-
- R_SExpr reduceLiteral(Literal &Orig) {
- return new (Arena) Literal(Orig);
- }
- template<class T>
- R_SExpr reduceLiteralT(LiteralT<T> &Orig) {
- return new (Arena) LiteralT<T>(Orig);
- }
- R_SExpr reduceLiteralPtr(LiteralPtr &Orig) {
- return new (Arena) LiteralPtr(Orig);
- }
-
- R_SExpr reduceFunction(Function &Orig, Variable *Nvd, R_SExpr E0) {
- return new (Arena) Function(Orig, Nvd, E0);
- }
- R_SExpr reduceSFunction(SFunction &Orig, Variable *Nvd, R_SExpr E0) {
- return new (Arena) SFunction(Orig, Nvd, E0);
- }
- R_SExpr reduceCode(Code &Orig, R_SExpr E0, R_SExpr E1) {
- return new (Arena) Code(Orig, E0, E1);
- }
- R_SExpr reduceField(Field &Orig, R_SExpr E0, R_SExpr E1) {
- return new (Arena) Field(Orig, E0, E1);
- }
-
- R_SExpr reduceApply(Apply &Orig, R_SExpr E0, R_SExpr E1) {
- return new (Arena) Apply(Orig, E0, E1);
- }
- R_SExpr reduceSApply(SApply &Orig, R_SExpr E0, R_SExpr E1) {
- return new (Arena) SApply(Orig, E0, E1);
- }
- R_SExpr reduceProject(Project &Orig, R_SExpr E0) {
- return new (Arena) Project(Orig, E0);
- }
- R_SExpr reduceCall(Call &Orig, R_SExpr E0) {
- return new (Arena) Call(Orig, E0);
- }
-
- R_SExpr reduceAlloc(Alloc &Orig, R_SExpr E0) {
- return new (Arena) Alloc(Orig, E0);
- }
- R_SExpr reduceLoad(Load &Orig, R_SExpr E0) {
- return new (Arena) Load(Orig, E0);
- }
- R_SExpr reduceStore(Store &Orig, R_SExpr E0, R_SExpr E1) {
- return new (Arena) Store(Orig, E0, E1);
- }
- R_SExpr reduceArrayIndex(ArrayIndex &Orig, R_SExpr E0, R_SExpr E1) {
- return new (Arena) ArrayIndex(Orig, E0, E1);
- }
- R_SExpr reduceArrayAdd(ArrayAdd &Orig, R_SExpr E0, R_SExpr E1) {
- return new (Arena) ArrayAdd(Orig, E0, E1);
- }
- R_SExpr reduceUnaryOp(UnaryOp &Orig, R_SExpr E0) {
- return new (Arena) UnaryOp(Orig, E0);
- }
- R_SExpr reduceBinaryOp(BinaryOp &Orig, R_SExpr E0, R_SExpr E1) {
- return new (Arena) BinaryOp(Orig, E0, E1);
- }
- R_SExpr reduceCast(Cast &Orig, R_SExpr E0) {
- return new (Arena) Cast(Orig, E0);
- }
-
- R_SExpr reduceSCFG(SCFG &Orig, Container<BasicBlock *> &Bbs) {
- return nullptr; // FIXME: implement CFG rewriting
- }
- R_BasicBlock reduceBasicBlock(BasicBlock &Orig, Container<Variable *> &As,
- Container<Variable *> &Is, R_SExpr T) {
- return nullptr; // FIXME: implement CFG rewriting
- }
- R_SExpr reducePhi(Phi &Orig, Container<R_SExpr> &As) {
- return new (Arena) Phi(Orig, std::move(As.Elems));
- }
- R_SExpr reduceGoto(Goto &Orig, BasicBlock *B) {
- return new (Arena) Goto(Orig, B, 0); // FIXME: set index
- }
- R_SExpr reduceBranch(Branch &O, R_SExpr C, BasicBlock *B0, BasicBlock *B1) {
- return new (Arena) Branch(O, C, B0, B1, 0, 0); // FIXME: set indices
- }
-
- R_SExpr reduceIdentifier(Identifier &Orig) {
- return new (Arena) Identifier(Orig);
- }
- R_SExpr reduceIfThenElse(IfThenElse &Orig, R_SExpr C, R_SExpr T, R_SExpr E) {
- return new (Arena) IfThenElse(Orig, C, T, E);
- }
- R_SExpr reduceLet(Let &Orig, Variable *Nvd, R_SExpr B) {
- return new (Arena) Let(Orig, Nvd, B);
- }
-
- // Create a new variable from orig, and push it onto the lexical scope.
- Variable *enterScope(Variable &Orig, R_SExpr E0) {
- return new (Arena) Variable(Orig, E0);
- }
- // Exit the lexical scope of orig.
- void exitScope(const Variable &Orig) {}
-
- void enterCFG(SCFG &Cfg) {}
- void exitCFG(SCFG &Cfg) {}
- void enterBasicBlock(BasicBlock &BB) {}
- void exitBasicBlock(BasicBlock &BB) {}
-
- // Map Variable references to their rewritten definitions.
- Variable *reduceVariableRef(Variable *Ovd) { return Ovd; }
-
- // Map BasicBlock references to their rewritten definitions.
- BasicBlock *reduceBasicBlockRef(BasicBlock *Obb) { return Obb; }
-};
-
-
-class SExprCopier : public CopyReducer<SExprCopier> {
-public:
- typedef SExpr *R_SExpr;
-
- SExprCopier(MemRegionRef A) : CopyReducer(A) { }
-
- // Create a copy of e in region a.
- static SExpr *copy(SExpr *E, MemRegionRef A) {
- SExprCopier Copier(A);
- return Copier.traverse(E, TRV_Normal);
- }
-};
-
-
-
// Base class for visit traversals.
class VisitReducerBase : public SimpleReducerBase {
public:
@@ -368,8 +227,8 @@ public:
R_SExpr reduceSCFG(SCFG &Orig, Container<BasicBlock *> Bbs) {
return Bbs.Success;
}
- R_BasicBlock reduceBasicBlock(BasicBlock &Orig, Container<Variable *> &As,
- Container<Variable *> &Is, R_SExpr T) {
+ R_BasicBlock reduceBasicBlock(BasicBlock &Orig, Container<R_SExpr> &As,
+ Container<R_SExpr> &Is, R_SExpr T) {
return (As.Success && Is.Success && T);
}
R_SExpr reducePhi(Phi &Orig, Container<R_SExpr> &As) {
@@ -381,6 +240,9 @@ public:
R_SExpr reduceBranch(Branch &O, R_SExpr C, BasicBlock *B0, BasicBlock *B1) {
return C;
}
+ R_SExpr reduceReturn(Return &O, R_SExpr E) {
+ return E;
+ }
R_SExpr reduceIdentifier(Identifier &Orig) {
return true;
@@ -433,7 +295,7 @@ public:
#include "ThreadSafetyOps.def"
#undef TIL_OPCODE_DEF
}
- llvm_unreachable("invalid enum");
+ return false;
}
};
@@ -514,9 +376,9 @@ public:
-inline std::ostream& operator<<(std::ostream& SS, llvm::StringRef R) {
- return SS.write(R.data(), R.size());
-}
+// inline std::ostream& operator<<(std::ostream& SS, StringRef R) {
+// return SS.write(R.data(), R.size());
+// }
// Pretty printer for TIL expressions
template <typename Self, typename StreamType>
@@ -587,6 +449,7 @@ protected:
case COP_Phi: return Prec_Atom;
case COP_Goto: return Prec_Atom;
case COP_Branch: return Prec_Atom;
+ case COP_Return: return Prec_Other;
case COP_Identifier: return Prec_Atom;
case COP_IfThenElse: return Prec_Other;
@@ -595,22 +458,29 @@ protected:
return Prec_MAX;
}
- void printBlockLabel(StreamType & SS, const BasicBlock *BB, unsigned index) {
+ void printBlockLabel(StreamType & SS, const BasicBlock *BB, int index) {
if (!BB) {
SS << "BB_null";
return;
}
SS << "BB_";
SS << BB->blockID();
- SS << ":";
- SS << index;
+ if (index >= 0) {
+ SS << ":";
+ SS << index;
+ }
}
- void printSExpr(const SExpr *E, StreamType &SS, unsigned P) {
+
+ void printSExpr(const SExpr *E, StreamType &SS, unsigned P, bool Sub=true) {
if (!E) {
self()->printNull(SS);
return;
}
+ if (Sub && E->block() && E->opcode() != COP_Variable) {
+ SS << "_x" << E->id();
+ return;
+ }
if (self()->precedence(E) > P) {
// Wrap expr in () if necessary.
SS << "(";
@@ -740,20 +610,11 @@ protected:
SS << E->clangDecl()->getNameAsString();
}
- void printVariable(const Variable *V, StreamType &SS, bool IsVarDecl = false) {
- if (!IsVarDecl && Cleanup) {
- const SExpr* E = getCanonicalVal(V);
- if (E != V) {
- printSExpr(E, SS, Prec_Atom);
- return;
- }
- }
- if (V->kind() == Variable::VK_LetBB)
- SS << V->name() << V->getBlockID() << "_" << V->getID();
- else if (CStyle && V->kind() == Variable::VK_SFun)
+ void printVariable(const Variable *V, StreamType &SS, bool IsVarDecl=false) {
+ if (CStyle && V->kind() == Variable::VK_SFun)
SS << "this";
else
- SS << V->name() << V->getID();
+ SS << V->name() << V->id();
}
void printFunction(const Function *E, StreamType &SS, unsigned sugared = 0) {
@@ -927,32 +788,38 @@ protected:
newline(SS);
}
+
+ void printBBInstr(const SExpr *E, StreamType &SS) {
+ bool Sub = false;
+ if (E->opcode() == COP_Variable) {
+ auto *V = cast<Variable>(E);
+ SS << "let " << V->name() << V->id() << " = ";
+ E = V->definition();
+ Sub = true;
+ }
+ else if (E->opcode() != COP_Store) {
+ SS << "let _x" << E->id() << " = ";
+ }
+ self()->printSExpr(E, SS, Prec_MAX, Sub);
+ SS << ";";
+ newline(SS);
+ }
+
void printBasicBlock(const BasicBlock *E, StreamType &SS) {
SS << "BB_" << E->blockID() << ":";
if (E->parent())
SS << " BB_" << E->parent()->blockID();
newline(SS);
- for (auto *A : E->arguments()) {
- SS << "let ";
- self()->printVariable(A, SS, true);
- SS << " = ";
- self()->printSExpr(A->definition(), SS, Prec_MAX);
- SS << ";";
- newline(SS);
- }
- for (auto *I : E->instructions()) {
- if (I->definition()->opcode() != COP_Store) {
- SS << "let ";
- self()->printVariable(I, SS, true);
- SS << " = ";
- }
- self()->printSExpr(I->definition(), SS, Prec_MAX);
- SS << ";";
- newline(SS);
- }
+
+ for (auto *A : E->arguments())
+ printBBInstr(A, SS);
+
+ for (auto *I : E->instructions())
+ printBBInstr(I, SS);
+
const SExpr *T = E->terminator();
if (T) {
- self()->printSExpr(T, SS, Prec_MAX);
+ self()->printSExpr(T, SS, Prec_MAX, false);
SS << ";";
newline(SS);
}
@@ -983,9 +850,14 @@ protected:
SS << "branch (";
self()->printSExpr(E->condition(), SS, Prec_MAX);
SS << ") ";
- printBlockLabel(SS, E->thenBlock(), E->thenIndex());
+ printBlockLabel(SS, E->thenBlock(), -1);
SS << " ";
- printBlockLabel(SS, E->elseBlock(), E->elseIndex());
+ printBlockLabel(SS, E->elseBlock(), -1);
+ }
+
+ void printReturn(const Return *E, StreamType &SS) {
+ SS << "return ";
+ self()->printSExpr(E->returnValue(), SS, Prec_Other);
}
void printIdentifier(const Identifier *E, StreamType &SS) {
Modified: cfe/trunk/include/clang/Analysis/Analyses/ThreadSafetyUtil.h
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/include/clang/Analysis/Analyses/ThreadSafetyUtil.h?rev=217556&r1=217555&r2=217556&view=diff
==============================================================================
--- cfe/trunk/include/clang/Analysis/Analyses/ThreadSafetyUtil.h (original)
+++ cfe/trunk/include/clang/Analysis/Analyses/ThreadSafetyUtil.h Wed Sep 10 17:12:52 2014
@@ -142,20 +142,35 @@ public:
assert(i < Size && "Array index out of bounds.");
return Data[i];
}
+ T &back() {
+ assert(Size && "No elements in the array.");
+ return Data[Size - 1];
+ }
+ const T &back() const {
+ assert(Size && "No elements in the array.");
+ return Data[Size - 1];
+ }
iterator begin() { return Data; }
+ iterator end() { return Data + Size; }
+
const_iterator begin() const { return Data; }
- iterator end() { return Data + Size; }
- const_iterator end() const { return Data + Size; }
+ const_iterator end() const { return Data + Size; }
const_iterator cbegin() const { return Data; }
- const_iterator cend() const { return Data + Size; }
+ const_iterator cend() const { return Data + Size; }
void push_back(const T &Elem) {
assert(Size < Capacity);
Data[Size++] = Elem;
}
+ // drop last n elements from array
+ void drop(unsigned n = 0) {
+ assert(Size > n);
+ Size -= n;
+ }
+
void setValues(unsigned Sz, const T& C) {
assert(Sz <= Capacity);
Size = Sz;
@@ -173,6 +188,37 @@ public:
return J - Osz;
}
+ // An adaptor to reverse a simple array
+ class ReverseAdaptor {
+ public:
+ ReverseAdaptor(SimpleArray &Array) : Array(Array) {}
+ // A reverse iterator used by the reverse adaptor
+ class Iterator {
+ public:
+ Iterator(T *Data) : Data(Data) {}
+ T &operator*() { return *Data; }
+ const T &operator*() const { return *Data; }
+ Iterator &operator++() {
+ --Data;
+ return *this;
+ }
+ bool operator!=(Iterator Other) { return Data != Other.Data; }
+
+ private:
+ T *Data;
+ };
+ Iterator begin() { return Array.end() - 1; }
+ Iterator end() { return Array.begin() - 1; }
+ const Iterator begin() const { return Array.end() - 1; }
+ const Iterator end() const { return Array.begin() - 1; }
+
+ private:
+ SimpleArray &Array;
+ };
+
+ const ReverseAdaptor reverse() const { return ReverseAdaptor(*this); }
+ ReverseAdaptor reverse() { return ReverseAdaptor(*this); }
+
private:
// std::max is annoying here, because it requires a reference,
// thus forcing InitialCapacity to be initialized outside the .h file.
@@ -187,6 +233,7 @@ private:
size_t Capacity;
};
+
} // end namespace til
@@ -312,6 +359,12 @@ private:
};
+inline std::ostream& operator<<(std::ostream& ss, const StringRef str) {
+ ss << str.data();
+ return ss;
+}
+
+
} // end namespace threadSafety
} // end namespace clang
Modified: cfe/trunk/lib/Analysis/ThreadSafetyCommon.cpp
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/lib/Analysis/ThreadSafetyCommon.cpp?rev=217556&r1=217555&r2=217556&view=diff
==============================================================================
--- cfe/trunk/lib/Analysis/ThreadSafetyCommon.cpp (original)
+++ cfe/trunk/lib/Analysis/ThreadSafetyCommon.cpp Wed Sep 10 17:12:52 2014
@@ -63,11 +63,9 @@ std::string getSourceLiteralString(const
namespace til {
// Return true if E is a variable that points to an incomplete Phi node.
-static bool isIncompleteVar(const SExpr *E) {
- if (const auto *V = dyn_cast<Variable>(E)) {
- if (const auto *Ph = dyn_cast<Phi>(V->definition()))
- return Ph->status() == Phi::PH_Incomplete;
- }
+static bool isIncompletePhi(const SExpr *E) {
+ if (const auto *Ph = dyn_cast<Phi>(E))
+ return Ph->status() == Phi::PH_Incomplete;
return false;
}
@@ -320,6 +318,8 @@ til::SExpr *SExprBuilder::translateCXXTh
const ValueDecl *getValueDeclFromSExpr(const til::SExpr *E) {
if (auto *V = dyn_cast<til::Variable>(E))
return V->clangDecl();
+ if (auto *Ph = dyn_cast<til::Phi>(E))
+ return Ph->clangDecl();
if (auto *P = dyn_cast<til::Project>(E))
return P->clangDecl();
if (auto *L = dyn_cast<til::LiteralPtr>(E))
@@ -641,14 +641,14 @@ SExprBuilder::translateDeclStmt(const De
// If E is trivial returns E.
til::SExpr *SExprBuilder::addStatement(til::SExpr* E, const Stmt *S,
const ValueDecl *VD) {
- if (!E || !CurrentBB || til::ThreadSafetyTIL::isTrivial(E))
+ if (!E || !CurrentBB || E->block() || til::ThreadSafetyTIL::isTrivial(E))
return E;
-
- til::Variable *V = new (Arena) til::Variable(E, VD);
- CurrentInstructions.push_back(V);
+ if (VD)
+ E = new (Arena) til::Variable(E, VD);
+ CurrentInstructions.push_back(E);
if (S)
- insertStmt(S, V);
- return V;
+ insertStmt(S, E);
+ return E;
}
@@ -705,11 +705,11 @@ void SExprBuilder::makePhiNodeVar(unsign
unsigned ArgIndex = CurrentBlockInfo->ProcessedPredecessors;
assert(ArgIndex > 0 && ArgIndex < NPreds);
- til::Variable *V = dyn_cast<til::Variable>(CurrentLVarMap[i].second);
- if (V && V->getBlockID() == CurrentBB->blockID()) {
+ til::SExpr *CurrE = CurrentLVarMap[i].second;
+ if (CurrE->block() == CurrentBB) {
// We already have a Phi node in the current block,
// so just add the new variable to the Phi node.
- til::Phi *Ph = dyn_cast<til::Phi>(V->definition());
+ til::Phi *Ph = dyn_cast<til::Phi>(CurrE);
assert(Ph && "Expecting Phi node.");
if (E)
Ph->values()[ArgIndex] = E;
@@ -718,27 +718,26 @@ void SExprBuilder::makePhiNodeVar(unsign
// Make a new phi node: phi(..., E)
// All phi args up to the current index are set to the current value.
- til::SExpr *CurrE = CurrentLVarMap[i].second;
til::Phi *Ph = new (Arena) til::Phi(Arena, NPreds);
Ph->values().setValues(NPreds, nullptr);
for (unsigned PIdx = 0; PIdx < ArgIndex; ++PIdx)
Ph->values()[PIdx] = CurrE;
if (E)
Ph->values()[ArgIndex] = E;
+ Ph->setClangDecl(CurrentLVarMap[i].first);
// If E is from a back-edge, or either E or CurrE are incomplete, then
// mark this node as incomplete; we may need to remove it later.
- if (!E || isIncompleteVar(E) || isIncompleteVar(CurrE)) {
+ if (!E || isIncompletePhi(E) || isIncompletePhi(CurrE)) {
Ph->setStatus(til::Phi::PH_Incomplete);
}
// Add Phi node to current block, and update CurrentLVarMap[i]
- auto *Var = new (Arena) til::Variable(Ph, CurrentLVarMap[i].first);
- CurrentArguments.push_back(Var);
+ CurrentArguments.push_back(Ph);
if (Ph->status() == til::Phi::PH_Incomplete)
- IncompleteArgs.push_back(Var);
+ IncompleteArgs.push_back(Ph);
CurrentLVarMap.makeWritable();
- CurrentLVarMap.elem(i).second = Var;
+ CurrentLVarMap.elem(i).second = Ph;
}
@@ -812,15 +811,13 @@ void SExprBuilder::mergePhiNodesBackEdge
unsigned ArgIndex = BBInfo[Blk->getBlockID()].ProcessedPredecessors;
assert(ArgIndex > 0 && ArgIndex < BB->numPredecessors());
- for (til::Variable *V : BB->arguments()) {
- til::Phi *Ph = dyn_cast_or_null<til::Phi>(V->definition());
+ for (til::SExpr *PE : BB->arguments()) {
+ til::Phi *Ph = dyn_cast_or_null<til::Phi>(PE);
assert(Ph && "Expecting Phi Node.");
assert(Ph->values()[ArgIndex] == nullptr && "Wrong index for back edge.");
- assert(V->clangDecl() && "No local variable for Phi node.");
- til::SExpr *E = lookupVarDecl(V->clangDecl());
+ til::SExpr *E = lookupVarDecl(Ph->clangDecl());
assert(E && "Couldn't find local variable for Phi node.");
-
Ph->values()[ArgIndex] = E;
}
}
@@ -899,8 +896,8 @@ void SExprBuilder::enterCFGBlockBody(con
// Push those arguments onto the basic block.
CurrentBB->arguments().reserve(
static_cast<unsigned>(CurrentArguments.size()), Arena);
- for (auto *V : CurrentArguments)
- CurrentBB->addArgument(V);
+ for (auto *A : CurrentArguments)
+ CurrentBB->addArgument(A);
}
@@ -934,7 +931,7 @@ void SExprBuilder::exitCFGBlockBody(cons
til::BasicBlock *BB = *It ? lookupBlock(*It) : nullptr;
// TODO: set index
unsigned Idx = BB ? BB->findPredecessorIndex(CurrentBB) : 0;
- til::SExpr *Tm = new (Arena) til::Goto(BB, Idx);
+ auto *Tm = new (Arena) til::Goto(BB, Idx);
CurrentBB->setTerminator(Tm);
}
else if (N == 2) {
@@ -942,9 +939,8 @@ void SExprBuilder::exitCFGBlockBody(cons
til::BasicBlock *BB1 = *It ? lookupBlock(*It) : nullptr;
++It;
til::BasicBlock *BB2 = *It ? lookupBlock(*It) : nullptr;
- unsigned Idx1 = BB1 ? BB1->findPredecessorIndex(CurrentBB) : 0;
- unsigned Idx2 = BB2 ? BB2->findPredecessorIndex(CurrentBB) : 0;
- til::SExpr *Tm = new (Arena) til::Branch(C, BB1, BB2, Idx1, Idx2);
+ // FIXME: make sure these arent' critical edges.
+ auto *Tm = new (Arena) til::Branch(C, BB1, BB2);
CurrentBB->setTerminator(Tm);
}
}
@@ -971,10 +967,9 @@ void SExprBuilder::exitCFGBlock(const CF
void SExprBuilder::exitCFG(const CFGBlock *Last) {
- for (auto *V : IncompleteArgs) {
- til::Phi *Ph = dyn_cast<til::Phi>(V->definition());
- if (Ph && Ph->status() == til::Phi::PH_Incomplete)
- simplifyIncompleteArg(V, Ph);
+ for (auto *Ph : IncompleteArgs) {
+ if (Ph->status() == til::Phi::PH_Incomplete)
+ simplifyIncompleteArg(Ph);
}
CurrentArguments.clear();
Modified: cfe/trunk/lib/Analysis/ThreadSafetyTIL.cpp
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/lib/Analysis/ThreadSafetyTIL.cpp?rev=217556&r1=217555&r2=217556&view=diff
==============================================================================
--- cfe/trunk/lib/Analysis/ThreadSafetyTIL.cpp (original)
+++ cfe/trunk/lib/Analysis/ThreadSafetyTIL.cpp Wed Sep 10 17:12:52 2014
@@ -48,12 +48,20 @@ StringRef getBinaryOpcodeString(TIL_Bina
}
+SExpr* Future::force() {
+ Status = FS_evaluating;
+ Result = compute();
+ Status = FS_done;
+ return Result;
+}
+
+
unsigned BasicBlock::addPredecessor(BasicBlock *Pred) {
unsigned Idx = Predecessors.size();
Predecessors.reserveCheck(1, Arena);
Predecessors.push_back(Pred);
- for (Variable *V : Args) {
- if (Phi* Ph = dyn_cast<Phi>(V->definition())) {
+ for (SExpr *E : Args) {
+ if (Phi* Ph = dyn_cast<Phi>(E)) {
Ph->values().reserveCheck(1, Arena);
Ph->values().push_back(nullptr);
}
@@ -61,105 +69,73 @@ unsigned BasicBlock::addPredecessor(Basi
return Idx;
}
+
void BasicBlock::reservePredecessors(unsigned NumPreds) {
Predecessors.reserve(NumPreds, Arena);
- for (Variable *V : Args) {
- if (Phi* Ph = dyn_cast<Phi>(V->definition())) {
+ for (SExpr *E : Args) {
+ if (Phi* Ph = dyn_cast<Phi>(E)) {
Ph->values().reserve(NumPreds, Arena);
}
}
}
-void BasicBlock::renumberVars() {
- unsigned VID = 0;
- for (Variable *V : Args) {
- V->setID(BlockID, VID++);
- }
- for (Variable *V : Instrs) {
- V->setID(BlockID, VID++);
- }
-}
-
-void SCFG::renumberVars() {
- for (BasicBlock *B : Blocks) {
- B->renumberVars();
- }
-}
-
-
// If E is a variable, then trace back through any aliases or redundant
// Phi nodes to find the canonical definition.
const SExpr *getCanonicalVal(const SExpr *E) {
- while (auto *V = dyn_cast<Variable>(E)) {
- const SExpr *D;
- do {
- if (V->kind() != Variable::VK_Let)
- return V;
- D = V->definition();
- auto *V2 = dyn_cast<Variable>(D);
- if (V2)
- V = V2;
- else
- break;
- } while (true);
-
- if (ThreadSafetyTIL::isTrivial(D))
- return D;
-
- if (const Phi *Ph = dyn_cast<Phi>(D)) {
+ while (true) {
+ if (auto *V = dyn_cast<Variable>(E)) {
+ if (V->kind() == Variable::VK_Let) {
+ E = V->definition();
+ continue;
+ }
+ }
+ if (const Phi *Ph = dyn_cast<Phi>(E)) {
if (Ph->status() == Phi::PH_SingleVal) {
E = Ph->values()[0];
continue;
}
}
- return V;
+ break;
}
return E;
}
-
// If E is a variable, then trace back through any aliases or redundant
// Phi nodes to find the canonical definition.
// The non-const version will simplify incomplete Phi nodes.
SExpr *simplifyToCanonicalVal(SExpr *E) {
- while (auto *V = dyn_cast<Variable>(E)) {
- SExpr *D;
- do {
+ while (true) {
+ if (auto *V = dyn_cast<Variable>(E)) {
if (V->kind() != Variable::VK_Let)
return V;
- D = V->definition();
- auto *V2 = dyn_cast<Variable>(D);
- if (V2)
- V = V2;
- else
- break;
- } while (true);
-
- if (ThreadSafetyTIL::isTrivial(D))
- return D;
-
- if (Phi *Ph = dyn_cast<Phi>(D)) {
+ // Eliminate redundant variables, e.g. x = y, or x = 5,
+ // but keep anything more complicated.
+ if (til::ThreadSafetyTIL::isTrivial(V->definition())) {
+ E = V->definition();
+ continue;
+ }
+ return V;
+ }
+ if (auto *Ph = dyn_cast<Phi>(E)) {
if (Ph->status() == Phi::PH_Incomplete)
- simplifyIncompleteArg(V, Ph);
-
+ simplifyIncompleteArg(Ph);
+ // Eliminate redundant Phi nodes.
if (Ph->status() == Phi::PH_SingleVal) {
E = Ph->values()[0];
continue;
}
}
- return V;
+ return E;
}
- return E;
}
-
// Trace the arguments of an incomplete Phi node to see if they have the same
// canonical definition. If so, mark the Phi node as redundant.
// getCanonicalVal() will recursively call simplifyIncompletePhi().
-void simplifyIncompleteArg(Variable *V, til::Phi *Ph) {
+void simplifyIncompleteArg(til::Phi *Ph) {
assert(Ph && Ph->status() == Phi::PH_Incomplete);
// eliminate infinite recursion -- assume that this node is not redundant.
@@ -168,18 +144,200 @@ void simplifyIncompleteArg(Variable *V,
SExpr *E0 = simplifyToCanonicalVal(Ph->values()[0]);
for (unsigned i=1, n=Ph->values().size(); i<n; ++i) {
SExpr *Ei = simplifyToCanonicalVal(Ph->values()[i]);
- if (Ei == V)
+ if (Ei == Ph)
continue; // Recursive reference to itself. Don't count.
if (Ei != E0) {
return; // Status is already set to MultiVal.
}
}
Ph->setStatus(Phi::PH_SingleVal);
- // Eliminate Redundant Phi node.
- V->setDefinition(Ph->values()[0]);
}
+// Renumbers the arguments and instructions to have unique, sequential IDs.
+int BasicBlock::renumberInstrs(int ID) {
+ for (auto *Arg : Args)
+ Arg->setID(this, ID++);
+ for (auto *Instr : Instrs)
+ Instr->setID(this, ID++);
+ TermInstr->setID(this, ID++);
+ return ID;
+}
+
+// Sorts the CFGs blocks using a reverse post-order depth-first traversal.
+// Each block will be written into the Blocks array in order, and its BlockID
+// will be set to the index in the array. Sorting should start from the entry
+// block, and ID should be the total number of blocks.
+int BasicBlock::topologicalSort(SimpleArray<BasicBlock*>& Blocks, int ID) {
+ if (Visited) return ID;
+ Visited = 1;
+ for (auto *Block : successors())
+ ID = Block->topologicalSort(Blocks, ID);
+ // set ID and update block array in place.
+ // We may lose pointers to unreachable blocks.
+ assert(ID > 0);
+ BlockID = --ID;
+ Blocks[BlockID] = this;
+ return ID;
+}
+
+// Performs a reverse topological traversal, starting from the exit block and
+// following back-edges. The dominator is serialized before any predecessors,
+// which guarantees that all blocks are serialized after their dominator and
+// before their post-dominator (because it's a reverse topological traversal).
+// ID should be initially set to 0.
+//
+// This sort assumes that (1) dominators have been computed, (2) there are no
+// critical edges, and (3) the entry block is reachable from the exit block
+// and no blocks are accessable via traversal of back-edges from the exit that
+// weren't accessable via forward edges from the entry.
+int BasicBlock::topologicalFinalSort(SimpleArray<BasicBlock*>& Blocks, int ID) {
+ // Visited is assumed to have been set by the topologicalSort. This pass
+ // assumes !Visited means that we've visited this node before.
+ if (!Visited) return ID;
+ Visited = 0;
+ if (DominatorNode.Parent)
+ ID = DominatorNode.Parent->topologicalFinalSort(Blocks, ID);
+ for (auto *Pred : Predecessors)
+ ID = Pred->topologicalFinalSort(Blocks, ID);
+ assert(ID < Blocks.size());
+ BlockID = ID++;
+ Blocks[BlockID] = this;
+ return ID;
+}
+
+// Computes the immediate dominator of the current block. Assumes that all of
+// its predecessors have already computed their dominators. This is achieved
+// by visiting the nodes in topological order.
+void BasicBlock::computeDominator() {
+ BasicBlock *Candidate = nullptr;
+ // Walk backwards from each predecessor to find the common dominator node.
+ for (auto *Pred : Predecessors) {
+ // Skip back-edges
+ if (Pred->BlockID >= BlockID) continue;
+ // If we don't yet have a candidate for dominator yet, take this one.
+ if (Candidate == nullptr) {
+ Candidate = Pred;
+ continue;
+ }
+ // Walk the alternate and current candidate back to find a common ancestor.
+ auto *Alternate = Pred;
+ while (Alternate != Candidate) {
+ if (Candidate->BlockID > Alternate->BlockID)
+ Candidate = Candidate->DominatorNode.Parent;
+ else
+ Alternate = Alternate->DominatorNode.Parent;
+ }
+ }
+ DominatorNode.Parent = Candidate;
+ DominatorNode.SizeOfSubTree = 1;
+}
+
+// Computes the immediate post-dominator of the current block. Assumes that all
+// of its successors have already computed their post-dominators. This is
+// achieved visiting the nodes in reverse topological order.
+void BasicBlock::computePostDominator() {
+ BasicBlock *Candidate = nullptr;
+ // Walk back from each predecessor to find the common post-dominator node.
+ for (auto *Succ : successors()) {
+ // Skip back-edges
+ if (Succ->BlockID <= BlockID) continue;
+ // If we don't yet have a candidate for post-dominator yet, take this one.
+ if (Candidate == nullptr) {
+ Candidate = Succ;
+ continue;
+ }
+ // Walk the alternate and current candidate back to find a common ancestor.
+ auto *Alternate = Succ;
+ while (Alternate != Candidate) {
+ if (Candidate->BlockID < Alternate->BlockID)
+ Candidate = Candidate->PostDominatorNode.Parent;
+ else
+ Alternate = Alternate->PostDominatorNode.Parent;
+ }
+ }
+ PostDominatorNode.Parent = Candidate;
+ PostDominatorNode.SizeOfSubTree = 1;
+}
+
+
+// Renumber instructions in all blocks
+void SCFG::renumberInstrs() {
+ int InstrID = 0;
+ for (auto *Block : Blocks)
+ InstrID = Block->renumberInstrs(InstrID);
+}
+
+
+static inline void computeNodeSize(BasicBlock *B,
+ BasicBlock::TopologyNode BasicBlock::*TN) {
+ BasicBlock::TopologyNode *N = &(B->*TN);
+ if (N->Parent) {
+ BasicBlock::TopologyNode *P = &(N->Parent->*TN);
+ // Initially set ID relative to the (as yet uncomputed) parent ID
+ N->NodeID = P->SizeOfSubTree;
+ P->SizeOfSubTree += N->SizeOfSubTree;
+ }
+}
+
+static inline void computeNodeID(BasicBlock *B,
+ BasicBlock::TopologyNode BasicBlock::*TN) {
+ BasicBlock::TopologyNode *N = &(B->*TN);
+ if (N->Parent) {
+ BasicBlock::TopologyNode *P = &(N->Parent->*TN);
+ N->NodeID += P->NodeID; // Fix NodeIDs relative to starting node.
+ }
+}
+
+
+// Normalizes a CFG. Normalization has a few major components:
+// 1) Removing unreachable blocks.
+// 2) Computing dominators and post-dominators
+// 3) Topologically sorting the blocks into the "Blocks" array.
+void SCFG::computeNormalForm() {
+ // Topologically sort the blocks starting from the entry block.
+ int NumUnreachableBlocks = Entry->topologicalSort(Blocks, Blocks.size());
+ if (NumUnreachableBlocks > 0) {
+ // If there were unreachable blocks shift everything down, and delete them.
+ for (size_t I = NumUnreachableBlocks, E = Blocks.size(); I < E; ++I) {
+ size_t NI = I - NumUnreachableBlocks;
+ Blocks[NI] = Blocks[I];
+ Blocks[NI]->BlockID = NI;
+ // FIXME: clean up predecessor pointers to unreachable blocks?
+ }
+ Blocks.drop(NumUnreachableBlocks);
+ }
+
+ // Compute dominators.
+ for (auto *Block : Blocks)
+ Block->computeDominator();
+
+ // Once dominators have been computed, the final sort may be performed.
+ int NumBlocks = Exit->topologicalFinalSort(Blocks, 0);
+ assert(NumBlocks == Blocks.size());
+ (void) NumBlocks;
+
+ // Renumber the instructions now that we have a final sort.
+ renumberInstrs();
+
+ // Compute post-dominators and compute the sizes of each node in the
+ // dominator tree.
+ for (auto *Block : Blocks.reverse()) {
+ Block->computePostDominator();
+ computeNodeSize(Block, &BasicBlock::DominatorNode);
+ }
+ // Compute the sizes of each node in the post-dominator tree and assign IDs in
+ // the dominator tree.
+ for (auto *Block : Blocks) {
+ computeNodeID(Block, &BasicBlock::DominatorNode);
+ computeNodeSize(Block, &BasicBlock::PostDominatorNode);
+ }
+ // Assign IDs in the post-dominator tree.
+ for (auto *Block : Blocks.reverse()) {
+ computeNodeID(Block, &BasicBlock::PostDominatorNode);
+ }
+}
+
} // end namespace til
} // end namespace threadSafety
} // end namespace clang
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