//===-- llvm/Function.h - Class to represent a single function --*- C++ -*-===//
//
-// This file contains the declaration of the Function class, which represents a
+// The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+// This file contains the declaration of the Function class, which represents a
// single function/procedure in LLVM.
//
// A function basically consists of a list of basic blocks, a list of arguments,
#ifndef LLVM_FUNCTION_H
#define LLVM_FUNCTION_H
-#include "llvm/GlobalValue.h"
-#include "llvm/BasicBlock.h"
#include "llvm/Argument.h"
+#include "llvm/Attributes.h"
+#include "llvm/BasicBlock.h"
+#include "llvm/CallingConv.h"
+#include "llvm/GlobalValue.h"
+#include "llvm/Support/Compiler.h"
+
+namespace llvm {
class FunctionType;
+class LLVMContext;
-// Traits for intrusive list of instructions...
+// Traits for intrusive list of basic blocks...
template<> struct ilist_traits<BasicBlock>
- : public SymbolTableListTraits<BasicBlock, Function, Function> {
+ : public SymbolTableListTraits<BasicBlock, Function> {
+
+ // createSentinel is used to get hold of the node that marks the end of the
+ // list... (same trick used here as in ilist_traits<Instruction>)
+ BasicBlock *createSentinel() const {
+ return static_cast<BasicBlock*>(&Sentinel);
+ }
+ static void destroySentinel(BasicBlock*) {}
- // createNode is used to create a node that marks the end of the list...
- static BasicBlock *createNode();
+ BasicBlock *provideInitialHead() const { return createSentinel(); }
+ BasicBlock *ensureHead(BasicBlock*) const { return createSentinel(); }
+ static void noteHead(BasicBlock*, BasicBlock*) {}
- static iplist<BasicBlock> &getList(Function *F);
+ static ValueSymbolTable *getSymTab(Function *ItemParent);
+private:
+ mutable ilist_half_node<BasicBlock> Sentinel;
};
template<> struct ilist_traits<Argument>
- : public SymbolTableListTraits<Argument, Function, Function> {
+ : public SymbolTableListTraits<Argument, Function> {
+
+ Argument *createSentinel() const {
+ return static_cast<Argument*>(&Sentinel);
+ }
+ static void destroySentinel(Argument*) {}
+
+ Argument *provideInitialHead() const { return createSentinel(); }
+ Argument *ensureHead(Argument*) const { return createSentinel(); }
+ static void noteHead(Argument*, Argument*) {}
- // createNode is used to create a node that marks the end of the list...
- static Argument *createNode();
- static iplist<Argument> &getList(Function *F);
+ static ValueSymbolTable *getSymTab(Function *ItemParent);
+private:
+ mutable ilist_half_node<Argument> Sentinel;
};
-class Function : public GlobalValue {
+class Function : public GlobalValue,
+ public ilist_node<Function> {
public:
typedef iplist<Argument> ArgumentListType;
typedef iplist<BasicBlock> BasicBlockListType;
// BasicBlock iterators...
typedef BasicBlockListType::iterator iterator;
typedef BasicBlockListType::const_iterator const_iterator;
- typedef std::reverse_iterator<const_iterator> const_reverse_iterator;
- typedef std::reverse_iterator<iterator> reverse_iterator;
- typedef ArgumentListType::iterator aiterator;
- typedef ArgumentListType::const_iterator const_aiterator;
- typedef std::reverse_iterator<const_aiterator> const_reverse_aiterator;
- typedef std::reverse_iterator<aiterator> reverse_aiterator;
+ typedef ArgumentListType::iterator arg_iterator;
+ typedef ArgumentListType::const_iterator const_arg_iterator;
private:
-
// Important things that make up a function!
- BasicBlockListType BasicBlocks; // The basic blocks
- ArgumentListType ArgumentList; // The formal arguments
+ BasicBlockListType BasicBlocks; ///< The basic blocks
+ mutable ArgumentListType ArgumentList; ///< The formal arguments
+ ValueSymbolTable *SymTab; ///< Symbol table of args/instructions
+ AttributeSet AttributeList; ///< Parameter attributes
- SymbolTable *SymTab, *ParentSymTab;
-
- friend class SymbolTableListTraits<Function, Module, Module>;
+ // HasLazyArguments is stored in Value::SubclassData.
+ /*bool HasLazyArguments;*/
+
+ // The Calling Convention is stored in Value::SubclassData.
+ /*CallingConv::ID CallingConvention;*/
+
+ friend class SymbolTableListTraits<Function, Module>;
void setParent(Module *parent);
- Function *Prev, *Next;
- void setNext(Function *N) { Next = N; }
- void setPrev(Function *N) { Prev = N; }
-public:
+ /// hasLazyArguments/CheckLazyArguments - The argument list of a function is
+ /// built on demand, so that the list isn't allocated until the first client
+ /// needs it. The hasLazyArguments predicate returns true if the arg list
+ /// hasn't been set up yet.
+ bool hasLazyArguments() const {
+ return getSubclassDataFromValue() & 1;
+ }
+ void CheckLazyArguments() const {
+ if (hasLazyArguments())
+ BuildLazyArguments();
+ }
+ void BuildLazyArguments() const;
+
+ Function(const Function&) LLVM_DELETED_FUNCTION;
+ void operator=(const Function&) LLVM_DELETED_FUNCTION;
+
/// Function ctor - If the (optional) Module argument is specified, the
/// function is automatically inserted into the end of the function list for
/// the module.
///
- Function(const FunctionType *Ty, bool isInternal, const std::string &N = "",
- Module *M = 0);
+ Function(FunctionType *Ty, LinkageTypes Linkage,
+ const Twine &N = "", Module *M = 0);
+
+public:
+ static Function *Create(FunctionType *Ty, LinkageTypes Linkage,
+ const Twine &N = "", Module *M = 0) {
+ return new(0) Function(Ty, Linkage, N, M);
+ }
+
~Function();
- // Specialize setName to handle symbol table majik...
- virtual void setName(const std::string &name, SymbolTable *ST = 0);
+ Type *getReturnType() const; // Return the type of the ret val
+ FunctionType *getFunctionType() const; // Return the FunctionType for me
+
+ /// getContext - Return a pointer to the LLVMContext associated with this
+ /// function, or NULL if this function is not bound to a context yet.
+ LLVMContext &getContext() const;
- const Type *getReturnType() const; // Return the type of the ret val
- const FunctionType *getFunctionType() const; // Return the FunctionType for me
+ /// isVarArg - Return true if this function takes a variable number of
+ /// arguments.
+ bool isVarArg() const;
- /// isExternal - Is the body of this function unknown? (the basic block list
- /// is empty if so) this is true for external functions, defined as forward
- /// "declare"ations
+ /// getIntrinsicID - This method returns the ID number of the specified
+ /// function, or Intrinsic::not_intrinsic if the function is not an
+ /// instrinsic, or if the pointer is null. This value is always defined to be
+ /// zero to allow easy checking for whether a function is intrinsic or not.
+ /// The particular intrinsic functions which correspond to this value are
+ /// defined in llvm/Intrinsics.h.
///
- virtual bool isExternal() const { return BasicBlocks.empty(); }
+ unsigned getIntrinsicID() const LLVM_READONLY;
+ bool isIntrinsic() const { return getIntrinsicID() != 0; }
+
+ /// getCallingConv()/setCallingConv(CC) - These method get and set the
+ /// calling convention of this function. The enum values for the known
+ /// calling conventions are defined in CallingConv.h.
+ CallingConv::ID getCallingConv() const {
+ return static_cast<CallingConv::ID>(getSubclassDataFromValue() >> 1);
+ }
+ void setCallingConv(CallingConv::ID CC) {
+ setValueSubclassData((getSubclassDataFromValue() & 1) |
+ (static_cast<unsigned>(CC) << 1));
+ }
+
+ /// getAttributes - Return the attribute list for this Function.
+ ///
+ const AttributeSet &getAttributes() const { return AttributeList; }
- // getNext/Prev - Return the next or previous function in the list. These
- // methods should never be used directly, and are only used to implement the
- // function list as part of the module.
- //
- Function *getNext() { return Next; }
- const Function *getNext() const { return Next; }
- Function *getPrev() { return Prev; }
- const Function *getPrev() const { return Prev; }
+ /// setAttributes - Set the attribute list for this Function.
+ ///
+ void setAttributes(const AttributeSet &attrs) { AttributeList = attrs; }
+
+ /// getFnAttributes - Return the function attributes for querying.
+ ///
+ Attributes getFnAttributes() const {
+ return AttributeList.getFnAttributes();
+ }
+
+ /// addFnAttr - Add function attributes to this function.
+ ///
+ void addFnAttr(Attributes::AttrVal N) {
+ // Function Attributes are stored at ~0 index
+ addAttribute(AttributeSet::FunctionIndex, Attributes::get(getContext(), N));
+ }
+
+ /// removeFnAttr - Remove function attributes from this function.
+ ///
+ void removeFnAttr(Attributes N) {
+ // Function Attributes are stored at ~0 index
+ removeAttribute(~0U, N);
+ }
+
+ /// hasGC/getGC/setGC/clearGC - The name of the garbage collection algorithm
+ /// to use during code generation.
+ bool hasGC() const;
+ const char *getGC() const;
+ void setGC(const char *Str);
+ void clearGC();
+
+
+ /// getRetAttributes - Return the return attributes for querying.
+ Attributes getRetAttributes() const {
+ return AttributeList.getRetAttributes();
+ }
+
+ /// getParamAttributes - Return the parameter attributes for querying.
+ Attributes getParamAttributes(unsigned Idx) const {
+ return AttributeList.getParamAttributes(Idx);
+ }
+
+ /// addAttribute - adds the attribute to the list of attributes.
+ void addAttribute(unsigned i, Attributes attr);
+
+ /// removeAttribute - removes the attribute from the list of attributes.
+ void removeAttribute(unsigned i, Attributes attr);
+
+ /// @brief Extract the alignment for a call or parameter (0=unknown).
+ unsigned getParamAlignment(unsigned i) const {
+ return AttributeList.getParamAlignment(i);
+ }
+
+ /// @brief Determine if the function does not access memory.
+ bool doesNotAccessMemory() const {
+ return getFnAttributes().hasAttribute(Attributes::ReadNone);
+ }
+ void setDoesNotAccessMemory() {
+ addFnAttr(Attributes::ReadNone);
+ }
- /// Get the underlying elements of the Function... both the argument list and
- /// basic block list are empty for external functions.
+ /// @brief Determine if the function does not access or only reads memory.
+ bool onlyReadsMemory() const {
+ return doesNotAccessMemory() ||
+ getFnAttributes().hasAttribute(Attributes::ReadOnly);
+ }
+ void setOnlyReadsMemory() {
+ addFnAttr(Attributes::ReadOnly);
+ }
+
+ /// @brief Determine if the function cannot return.
+ bool doesNotReturn() const {
+ return getFnAttributes().hasAttribute(Attributes::NoReturn);
+ }
+ void setDoesNotReturn() {
+ addFnAttr(Attributes::NoReturn);
+ }
+
+ /// @brief Determine if the function cannot unwind.
+ bool doesNotThrow() const {
+ return getFnAttributes().hasAttribute(Attributes::NoUnwind);
+ }
+ void setDoesNotThrow() {
+ addFnAttr(Attributes::NoUnwind);
+ }
+
+ /// @brief True if the ABI mandates (or the user requested) that this
+ /// function be in a unwind table.
+ bool hasUWTable() const {
+ return getFnAttributes().hasAttribute(Attributes::UWTable);
+ }
+ void setHasUWTable() {
+ addFnAttr(Attributes::UWTable);
+ }
+
+ /// @brief True if this function needs an unwind table.
+ bool needsUnwindTableEntry() const {
+ return hasUWTable() || !doesNotThrow();
+ }
+
+ /// @brief Determine if the function returns a structure through first
+ /// pointer argument.
+ bool hasStructRetAttr() const {
+ return getParamAttributes(1).hasAttribute(Attributes::StructRet);
+ }
+
+ /// @brief Determine if the parameter does not alias other parameters.
+ /// @param n The parameter to check. 1 is the first parameter, 0 is the return
+ bool doesNotAlias(unsigned n) const {
+ return getParamAttributes(n).hasAttribute(Attributes::NoAlias);
+ }
+ void setDoesNotAlias(unsigned n) {
+ addAttribute(n, Attributes::get(getContext(), Attributes::NoAlias));
+ }
+
+ /// @brief Determine if the parameter can be captured.
+ /// @param n The parameter to check. 1 is the first parameter, 0 is the return
+ bool doesNotCapture(unsigned n) const {
+ return getParamAttributes(n).hasAttribute(Attributes::NoCapture);
+ }
+ void setDoesNotCapture(unsigned n) {
+ addAttribute(n, Attributes::get(getContext(), Attributes::NoCapture));
+ }
+
+ /// copyAttributesFrom - copy all additional attributes (those not needed to
+ /// create a Function) from the Function Src to this one.
+ void copyAttributesFrom(const GlobalValue *Src);
+
+ /// deleteBody - This method deletes the body of the function, and converts
+ /// the linkage to external.
+ ///
+ void deleteBody() {
+ dropAllReferences();
+ setLinkage(ExternalLinkage);
+ }
+
+ /// removeFromParent - This method unlinks 'this' from the containing module,
+ /// but does not delete it.
///
- const ArgumentListType &getArgumentList() const { return ArgumentList; }
- ArgumentListType &getArgumentList() { return ArgumentList; }
+ virtual void removeFromParent();
+
+ /// eraseFromParent - This method unlinks 'this' from the containing module
+ /// and deletes it.
+ ///
+ virtual void eraseFromParent();
+
+
+ /// Get the underlying elements of the Function... the basic block list is
+ /// empty for external functions.
+ ///
+ const ArgumentListType &getArgumentList() const {
+ CheckLazyArguments();
+ return ArgumentList;
+ }
+ ArgumentListType &getArgumentList() {
+ CheckLazyArguments();
+ return ArgumentList;
+ }
+ static iplist<Argument> Function::*getSublistAccess(Argument*) {
+ return &Function::ArgumentList;
+ }
const BasicBlockListType &getBasicBlockList() const { return BasicBlocks; }
BasicBlockListType &getBasicBlockList() { return BasicBlocks; }
+ static iplist<BasicBlock> Function::*getSublistAccess(BasicBlock*) {
+ return &Function::BasicBlocks;
+ }
- const BasicBlock &getEntryNode() const { return front(); }
- BasicBlock &getEntryNode() { return front(); }
+ const BasicBlock &getEntryBlock() const { return front(); }
+ BasicBlock &getEntryBlock() { return front(); }
//===--------------------------------------------------------------------===//
// Symbol Table Accessing functions...
- /// hasSymbolTable() - Returns true if there is a symbol table allocated to
- /// this object AND if there is at least one name in it!
- ///
- bool hasSymbolTable() const;
-
- /// getSymbolTable() - CAUTION: The current symbol table may be null if there
- /// are no names (ie, the symbol table is empty)
+ /// getSymbolTable() - Return the symbol table...
///
- inline SymbolTable *getSymbolTable() { return SymTab; }
- inline const SymbolTable *getSymbolTable() const { return SymTab; }
+ inline ValueSymbolTable &getValueSymbolTable() { return *SymTab; }
+ inline const ValueSymbolTable &getValueSymbolTable() const { return *SymTab; }
- /// getSymbolTableSure is guaranteed to not return a null pointer, because if
- /// the function does not already have a symtab, one is created. Use this if
- /// you intend to put something into the symbol table for the function.
- ///
- SymbolTable *getSymbolTableSure(); // Implemented in Value.cpp
-
//===--------------------------------------------------------------------===//
// BasicBlock iterator forwarding functions
//
iterator end () { return BasicBlocks.end(); }
const_iterator end () const { return BasicBlocks.end(); }
- reverse_iterator rbegin() { return BasicBlocks.rbegin(); }
- const_reverse_iterator rbegin() const { return BasicBlocks.rbegin(); }
- reverse_iterator rend () { return BasicBlocks.rend(); }
- const_reverse_iterator rend () const { return BasicBlocks.rend(); }
-
- unsigned size() const { return BasicBlocks.size(); }
+ size_t size() const { return BasicBlocks.size(); }
bool empty() const { return BasicBlocks.empty(); }
const BasicBlock &front() const { return BasicBlocks.front(); }
BasicBlock &front() { return BasicBlocks.front(); }
- const BasicBlock &back() const { return BasicBlocks.back(); }
- BasicBlock &back() { return BasicBlocks.back(); }
+ const BasicBlock &back() const { return BasicBlocks.back(); }
+ BasicBlock &back() { return BasicBlocks.back(); }
//===--------------------------------------------------------------------===//
// Argument iterator forwarding functions
//
- aiterator abegin() { return ArgumentList.begin(); }
- const_aiterator abegin() const { return ArgumentList.begin(); }
- aiterator aend () { return ArgumentList.end(); }
- const_aiterator aend () const { return ArgumentList.end(); }
+ arg_iterator arg_begin() {
+ CheckLazyArguments();
+ return ArgumentList.begin();
+ }
+ const_arg_iterator arg_begin() const {
+ CheckLazyArguments();
+ return ArgumentList.begin();
+ }
+ arg_iterator arg_end() {
+ CheckLazyArguments();
+ return ArgumentList.end();
+ }
+ const_arg_iterator arg_end() const {
+ CheckLazyArguments();
+ return ArgumentList.end();
+ }
- reverse_aiterator arbegin() { return ArgumentList.rbegin(); }
- const_reverse_aiterator arbegin() const { return ArgumentList.rbegin(); }
- reverse_aiterator arend () { return ArgumentList.rend(); }
- const_reverse_aiterator arend () const { return ArgumentList.rend(); }
+ size_t arg_size() const;
+ bool arg_empty() const;
- unsigned asize() const { return ArgumentList.size(); }
- bool aempty() const { return ArgumentList.empty(); }
- const Argument &afront() const { return ArgumentList.front(); }
- Argument &afront() { return ArgumentList.front(); }
- const Argument &aback() const { return ArgumentList.back(); }
- Argument &aback() { return ArgumentList.back(); }
+ /// viewCFG - This function is meant for use from the debugger. You can just
+ /// say 'call F->viewCFG()' and a ghostview window should pop up from the
+ /// program, displaying the CFG of the current function with the code for each
+ /// basic block inside. This depends on there being a 'dot' and 'gv' program
+ /// in your path.
+ ///
+ void viewCFG() const;
- virtual void print(std::ostream &OS) const;
+ /// viewCFGOnly - This function is meant for use from the debugger. It works
+ /// just like viewCFG, but it does not include the contents of basic blocks
+ /// into the nodes, just the label. If you are only interested in the CFG
+ /// this can make the graph smaller.
+ ///
+ void viewCFGOnly() const;
/// Methods for support type inquiry through isa, cast, and dyn_cast:
- static inline bool classof(const Function *) { return true; }
static inline bool classof(const Value *V) {
- return V->getValueType() == Value::FunctionVal;
+ return V->getValueID() == Value::FunctionVal;
}
- /// dropAllReferences() - This function causes all the subinstructions to "let
+ /// dropAllReferences() - This method causes all the subinstructions to "let
/// go" of all references that they are maintaining. This allows one to
- /// 'delete' a whole class at a time, even though there may be circular
+ /// 'delete' a whole module at a time, even though there may be circular
/// references... first all references are dropped, and all use counts go to
- /// zero. Then everything is delete'd for real. Note that no operations are
- /// valid on an object that has "dropped all references", except operator
+ /// zero. Then everything is deleted for real. Note that no operations are
+ /// valid on an object that has "dropped all references", except operator
/// delete.
///
+ /// Since no other object in the module can have references into the body of a
+ /// function, dropping all references deletes the entire body of the function,
+ /// including any contained basic blocks.
+ ///
void dropAllReferences();
+
+ /// hasAddressTaken - returns true if there are any uses of this function
+ /// other than direct calls or invokes to it, or blockaddress expressions.
+ /// Optionally passes back an offending user for diagnostic purposes.
+ ///
+ bool hasAddressTaken(const User** = 0) const;
+
+ /// isDefTriviallyDead - Return true if it is trivially safe to remove
+ /// this function definition from the module (because it isn't externally
+ /// visible, does not have its address taken, and has no callers). To make
+ /// this more accurate, call removeDeadConstantUsers first.
+ bool isDefTriviallyDead() const;
+
+ /// callsFunctionThatReturnsTwice - Return true if the function has a call to
+ /// setjmp or other function that gcc recognizes as "returning twice".
+ bool callsFunctionThatReturnsTwice() const;
+
+private:
+ // Shadow Value::setValueSubclassData with a private forwarding method so that
+ // subclasses cannot accidentally use it.
+ void setValueSubclassData(unsigned short D) {
+ Value::setValueSubclassData(D);
+ }
};
+inline ValueSymbolTable *
+ilist_traits<BasicBlock>::getSymTab(Function *F) {
+ return F ? &F->getValueSymbolTable() : 0;
+}
+
+inline ValueSymbolTable *
+ilist_traits<Argument>::getSymTab(Function *F) {
+ return F ? &F->getValueSymbolTable() : 0;
+}
+
+} // End llvm namespace
+
#endif