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//===- CallSite.h - Abstract Call & Invoke instrs ---------------*- C++ -*-===//
//
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
// See https://llvm.org/LICENSE.txt for license information.
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
//
//===----------------------------------------------------------------------===//
//
// This file defines the CallSite class, which is a handy wrapper for code that
// wants to treat Call, Invoke and CallBr instructions in a generic way. When
// in non-mutation context (e.g. an analysis) ImmutableCallSite should be used.
// Finally, when some degree of customization is necessary between these two
// extremes, CallSiteBase<> can be supplied with fine-tuned parameters.
//
// NOTE: These classes are supposed to have "value semantics". So they should be
// passed by value, not by reference; they should not be "new"ed or "delete"d.
// They are efficiently copyable, assignable and constructable, with cost
// equivalent to copying a pointer (notice that they have only a single data
// member). The internal representation carries a flag which indicates which of
// the three variants is enclosed. This allows for cheaper checks when various
// accessors of CallSite are employed.
//
//===----------------------------------------------------------------------===//
#ifndef LLVM_IR_CALLSITE_H
#define LLVM_IR_CALLSITE_H
#include "llvm/ADT/Optional.h"
#include "llvm/ADT/PointerIntPair.h"
#include "llvm/ADT/iterator_range.h"
#include "llvm/IR/Attributes.h"
#include "llvm/IR/CallingConv.h"
#include "llvm/IR/Function.h"
#include "llvm/IR/InstrTypes.h"
#include "llvm/IR/Instruction.h"
#include "llvm/IR/Instructions.h"
#include "llvm/IR/Use.h"
#include "llvm/IR/User.h"
#include "llvm/IR/Value.h"
#include "llvm/Support/Casting.h"
#include <cassert>
#include <cstdint>
#include <iterator>
namespace llvm {
namespace Intrinsic {
typedef unsigned ID;
}
template <typename FunTy = const Function, typename BBTy = const BasicBlock,
typename ValTy = const Value, typename UserTy = const User,
typename UseTy = const Use, typename InstrTy = const Instruction,
typename CallTy = const CallInst,
typename InvokeTy = const InvokeInst,
typename CallBrTy = const CallBrInst,
typename IterTy = User::const_op_iterator>
class CallSiteBase {
protected:
PointerIntPair<InstrTy *, 2, int> I;
CallSiteBase() = default;
CallSiteBase(CallTy *CI) : I(CI, 1) { assert(CI); }
CallSiteBase(InvokeTy *II) : I(II, 0) { assert(II); }
CallSiteBase(CallBrTy *CBI) : I(CBI, 2) { assert(CBI); }
explicit CallSiteBase(ValTy *II) { *this = get(II); }
private:
/// This static method is like a constructor. It will create an appropriate
/// call site for a Call, Invoke or CallBr instruction, but it can also create
/// a null initialized CallSiteBase object for something which is NOT a call
/// site.
static CallSiteBase get(ValTy *V) {
if (InstrTy *II = dyn_cast<InstrTy>(V)) {
if (II->getOpcode() == Instruction::Call)
return CallSiteBase(static_cast<CallTy*>(II));
if (II->getOpcode() == Instruction::Invoke)
return CallSiteBase(static_cast<InvokeTy*>(II));
if (II->getOpcode() == Instruction::CallBr)
return CallSiteBase(static_cast<CallBrTy *>(II));
}
return CallSiteBase();
}
public:
/// Return true if a CallInst is enclosed.
bool isCall() const { return I.getInt() == 1; }
/// Return true if a InvokeInst is enclosed. !I.getInt() may also signify a
/// NULL instruction pointer, so check that.
bool isInvoke() const { return getInstruction() && I.getInt() == 0; }
/// Return true if a CallBrInst is enclosed.
bool isCallBr() const { return I.getInt() == 2; }
InstrTy *getInstruction() const { return I.getPointer(); }
InstrTy *operator->() const { return I.getPointer(); }
explicit operator bool() const { return I.getPointer(); }
/// Get the basic block containing the call site.
BBTy* getParent() const { return getInstruction()->getParent(); }
/// Return the pointer to function that is being called.
ValTy *getCalledValue() const {
assert(getInstruction() && "Not a call, invoke or callbr instruction!");
return *getCallee();
}
/// Return the function being called if this is a direct call, otherwise
/// return null (if it's an indirect call).
FunTy *getCalledFunction() const {
return dyn_cast<FunTy>(getCalledValue());
}
/// Return true if the callsite is an indirect call.
bool isIndirectCall() const {
const Value *V = getCalledValue();
if (!V)
return false;
if (isa<FunTy>(V) || isa<Constant>(V))
return false;
if (const CallBase *CB = dyn_cast<CallBase>(getInstruction()))
if (CB->isInlineAsm())
return false;
return true;
}
/// Set the callee to the specified value. Unlike the function of the same
/// name on CallBase, does not modify the type!
void setCalledFunction(Value *V) {
assert(getInstruction() && "Not a call, callbr, or invoke instruction!");
assert(cast<PointerType>(V->getType())->getElementType() ==
cast<CallBase>(getInstruction())->getFunctionType() &&
"New callee type does not match FunctionType on call");
*getCallee() = V;
}
/// Return the intrinsic ID of the intrinsic called by this CallSite,
/// or Intrinsic::not_intrinsic if the called function is not an
/// intrinsic, or if this CallSite is an indirect call.
Intrinsic::ID getIntrinsicID() const {
if (auto *F = getCalledFunction())
return F->getIntrinsicID();
// Don't use Intrinsic::not_intrinsic, as it will require pulling
// Intrinsics.h into every header that uses CallSite.
return static_cast<Intrinsic::ID>(0);
}
/// Determine whether the passed iterator points to the callee operand's Use.
bool isCallee(Value::const_user_iterator UI) const {
return isCallee(&UI.getUse());
}
/// Determine whether this Use is the callee operand's Use.
bool isCallee(const Use *U) const { return getCallee() == U; }
/// Determine whether the passed iterator points to an argument operand.
bool isArgOperand(Value::const_user_iterator UI) const {
return isArgOperand(&UI.getUse());
}
/// Determine whether the passed use points to an argument operand.
bool isArgOperand(const Use *U) const {
assert(getInstruction() == U->getUser());
return arg_begin() <= U && U < arg_end();
}
/// Determine whether the passed iterator points to a bundle operand.
bool isBundleOperand(Value::const_user_iterator UI) const {
return isBundleOperand(&UI.getUse());
}
/// Determine whether the passed use points to a bundle operand.
bool isBundleOperand(const Use *U) const {
assert(getInstruction() == U->getUser());
if (!hasOperandBundles())
return false;
unsigned OperandNo = U - (*this)->op_begin();
return getBundleOperandsStartIndex() <= OperandNo &&
OperandNo < getBundleOperandsEndIndex();
}
/// Determine whether the passed iterator points to a data operand.
bool isDataOperand(Value::const_user_iterator UI) const {
return isDataOperand(&UI.getUse());
}
/// Determine whether the passed use points to a data operand.
bool isDataOperand(const Use *U) const {
return data_operands_begin() <= U && U < data_operands_end();
}
ValTy *getArgument(unsigned ArgNo) const {
assert(arg_begin() + ArgNo < arg_end() && "Argument # out of range!");
return *(arg_begin() + ArgNo);
}
void setArgument(unsigned ArgNo, Value* newVal) {
assert(getInstruction() && "Not a call, invoke or callbr instruction!");
assert(arg_begin() + ArgNo < arg_end() && "Argument # out of range!");
getInstruction()->setOperand(ArgNo, newVal);
}
/// Given a value use iterator, returns the argument that corresponds to it.
/// Iterator must actually correspond to an argument.
unsigned getArgumentNo(Value::const_user_iterator I) const {
return getArgumentNo(&I.getUse());
}
/// Given a use for an argument, get the argument number that corresponds to
/// it.
unsigned getArgumentNo(const Use *U) const {
assert(getInstruction() && "Not a call, invoke or callbr instruction!");
assert(isArgOperand(U) && "Argument # out of range!");
return U - arg_begin();
}
/// The type of iterator to use when looping over actual arguments at this
/// call site.
using arg_iterator = IterTy;
iterator_range<IterTy> args() const {
return make_range(arg_begin(), arg_end());
}
bool arg_empty() const { return arg_end() == arg_begin(); }
unsigned arg_size() const { return unsigned(arg_end() - arg_begin()); }
/// Given a value use iterator, return the data operand corresponding to it.
/// Iterator must actually correspond to a data operand.
unsigned getDataOperandNo(Value::const_user_iterator UI) const {
return getDataOperandNo(&UI.getUse());
}
/// Given a use for a data operand, get the data operand number that
/// corresponds to it.
unsigned getDataOperandNo(const Use *U) const {
assert(getInstruction() && "Not a call, invoke or callbr instruction!");
assert(isDataOperand(U) && "Data operand # out of range!");
return U - data_operands_begin();
}
/// Type of iterator to use when looping over data operands at this call site
/// (see below).
using data_operand_iterator = IterTy;
/// data_operands_begin/data_operands_end - Return iterators iterating over
/// the call / invoke / callbr argument list and bundle operands. For invokes,
/// this is the set of instruction operands except the invoke target and the
/// two successor blocks; for calls this is the set of instruction operands
/// except the call target; for callbrs the number of labels to skip must be
/// determined first.
IterTy data_operands_begin() const {
assert(getInstruction() && "Not a call or invoke instruction!");
return cast<CallBase>(getInstruction())->data_operands_begin();
}
IterTy data_operands_end() const {
assert(getInstruction() && "Not a call or invoke instruction!");
return cast<CallBase>(getInstruction())->data_operands_end();
}
iterator_range<IterTy> data_ops() const {
return make_range(data_operands_begin(), data_operands_end());
}
bool data_operands_empty() const {
return data_operands_end() == data_operands_begin();
}
unsigned data_operands_size() const {
return std::distance(data_operands_begin(), data_operands_end());
}
/// Return the type of the instruction that generated this call site.
Type *getType() const { return (*this)->getType(); }
/// Return the caller function for this call site.
FunTy *getCaller() const { return (*this)->getParent()->getParent(); }
/// Tests if this call site must be tail call optimized. Only a CallInst can
/// be tail call optimized.
bool isMustTailCall() const {
return isCall() && cast<CallInst>(getInstruction())->isMustTailCall();
}
/// Tests if this call site is marked as a tail call.
bool isTailCall() const {
return isCall() && cast<CallInst>(getInstruction())->isTailCall();
}
#define CALLSITE_DELEGATE_GETTER(METHOD) \
InstrTy *II = getInstruction(); \
return isCall() ? cast<CallInst>(II)->METHOD \
: isCallBr() ? cast<CallBrInst>(II)->METHOD \
: cast<InvokeInst>(II)->METHOD
#define CALLSITE_DELEGATE_SETTER(METHOD) \
InstrTy *II = getInstruction(); \
if (isCall()) \
cast<CallInst>(II)->METHOD; \
else if (isCallBr()) \
cast<CallBrInst>(II)->METHOD; \
else \
cast<InvokeInst>(II)->METHOD
unsigned getNumArgOperands() const {
CALLSITE_DELEGATE_GETTER(getNumArgOperands());
}
ValTy *getArgOperand(unsigned i) const {
CALLSITE_DELEGATE_GETTER(getArgOperand(i));
}
ValTy *getReturnedArgOperand() const {
CALLSITE_DELEGATE_GETTER(getReturnedArgOperand());
}
bool isInlineAsm() const {
return cast<CallBase>(getInstruction())->isInlineAsm();
}
/// Get the calling convention of the call.
CallingConv::ID getCallingConv() const {
CALLSITE_DELEGATE_GETTER(getCallingConv());
}
/// Set the calling convention of the call.
void setCallingConv(CallingConv::ID CC) {
CALLSITE_DELEGATE_SETTER(setCallingConv(CC));
}
FunctionType *getFunctionType() const {
CALLSITE_DELEGATE_GETTER(getFunctionType());
}
void mutateFunctionType(FunctionType *Ty) const {
CALLSITE_DELEGATE_SETTER(mutateFunctionType(Ty));
}
/// Get the parameter attributes of the call.
AttributeList getAttributes() const {
CALLSITE_DELEGATE_GETTER(getAttributes());
}
/// Set the parameter attributes of the call.
void setAttributes(AttributeList PAL) {
CALLSITE_DELEGATE_SETTER(setAttributes(PAL));
}
void addAttribute(unsigned i, Attribute::AttrKind Kind) {
CALLSITE_DELEGATE_SETTER(addAttribute(i, Kind));
}
void addAttribute(unsigned i, Attribute Attr) {
CALLSITE_DELEGATE_SETTER(addAttribute(i, Attr));
}
void addParamAttr(unsigned ArgNo, Attribute::AttrKind Kind) {
CALLSITE_DELEGATE_SETTER(addParamAttr(ArgNo, Kind));
}
void removeAttribute(unsigned i, Attribute::AttrKind Kind) {
CALLSITE_DELEGATE_SETTER(removeAttribute(i, Kind));
}
void removeAttribute(unsigned i, StringRef Kind) {
CALLSITE_DELEGATE_SETTER(removeAttribute(i, Kind));
}
void removeParamAttr(unsigned ArgNo, Attribute::AttrKind Kind) {
CALLSITE_DELEGATE_SETTER(removeParamAttr(ArgNo, Kind));
}
/// Return true if this function has the given attribute.
bool hasFnAttr(Attribute::AttrKind Kind) const {
CALLSITE_DELEGATE_GETTER(hasFnAttr(Kind));
}
/// Return true if this function has the given attribute.
bool hasFnAttr(StringRef Kind) const {
CALLSITE_DELEGATE_GETTER(hasFnAttr(Kind));
}
/// Return true if this return value has the given attribute.
bool hasRetAttr(Attribute::AttrKind Kind) const {
CALLSITE_DELEGATE_GETTER(hasRetAttr(Kind));
}
/// Return true if the call or the callee has the given attribute.
bool paramHasAttr(unsigned ArgNo, Attribute::AttrKind Kind) const {
CALLSITE_DELEGATE_GETTER(paramHasAttr(ArgNo, Kind));
}
Attribute getAttribute(unsigned i, Attribute::AttrKind Kind) const {
CALLSITE_DELEGATE_GETTER(getAttribute(i, Kind));
}
Attribute getAttribute(unsigned i, StringRef Kind) const {
CALLSITE_DELEGATE_GETTER(getAttribute(i, Kind));
}
/// Return true if the data operand at index \p i directly or indirectly has
/// the attribute \p A.
///
/// Normal call, invoke or callbr arguments have per operand attributes, as
/// specified in the attribute set attached to this instruction, while operand
/// bundle operands may have some attributes implied by the type of its
/// containing operand bundle.
bool dataOperandHasImpliedAttr(unsigned i, Attribute::AttrKind Kind) const {
CALLSITE_DELEGATE_GETTER(dataOperandHasImpliedAttr(i, Kind));
}
/// Extract the alignment of the return value.
unsigned getRetAlignment() const {
CALLSITE_DELEGATE_GETTER(getRetAlignment());
}
/// Extract the alignment for a call or parameter (0=unknown).
unsigned getParamAlignment(unsigned ArgNo) const {
CALLSITE_DELEGATE_GETTER(getParamAlignment(ArgNo));
}
/// Extract the byval type for a call or parameter (nullptr=unknown).
Type *getParamByValType(unsigned ArgNo) const {
CALLSITE_DELEGATE_GETTER(getParamByValType(ArgNo));
}
/// Extract the number of dereferenceable bytes for a call or parameter
/// (0=unknown).
uint64_t getDereferenceableBytes(unsigned i) const {
CALLSITE_DELEGATE_GETTER(getDereferenceableBytes(i));
}
/// Extract the number of dereferenceable_or_null bytes for a call or
/// parameter (0=unknown).
uint64_t getDereferenceableOrNullBytes(unsigned i) const {
CALLSITE_DELEGATE_GETTER(getDereferenceableOrNullBytes(i));
}
/// Determine if the return value is marked with NoAlias attribute.
bool returnDoesNotAlias() const {
CALLSITE_DELEGATE_GETTER(returnDoesNotAlias());
}
/// Return true if the call should not be treated as a call to a builtin.
bool isNoBuiltin() const {
CALLSITE_DELEGATE_GETTER(isNoBuiltin());
}
/// Return true if the call requires strict floating point semantics.
bool isStrictFP() const {
CALLSITE_DELEGATE_GETTER(isStrictFP());
}
/// Return true if the call should not be inlined.
bool isNoInline() const {
CALLSITE_DELEGATE_GETTER(isNoInline());
}
void setIsNoInline(bool Value = true) {
CALLSITE_DELEGATE_SETTER(setIsNoInline(Value));
}
/// Determine if the call does not access memory.
bool doesNotAccessMemory() const {
CALLSITE_DELEGATE_GETTER(doesNotAccessMemory());
}
void setDoesNotAccessMemory() {
CALLSITE_DELEGATE_SETTER(setDoesNotAccessMemory());
}
/// Determine if the call does not access or only reads memory.
bool onlyReadsMemory() const {
CALLSITE_DELEGATE_GETTER(onlyReadsMemory());
}
void setOnlyReadsMemory() {
CALLSITE_DELEGATE_SETTER(setOnlyReadsMemory());
}
/// Determine if the call does not access or only writes memory.
bool doesNotReadMemory() const {
CALLSITE_DELEGATE_GETTER(doesNotReadMemory());
}
void setDoesNotReadMemory() {
CALLSITE_DELEGATE_SETTER(setDoesNotReadMemory());
}
/// Determine if the call can access memmory only using pointers based
/// on its arguments.
bool onlyAccessesArgMemory() const {
CALLSITE_DELEGATE_GETTER(onlyAccessesArgMemory());
}
void setOnlyAccessesArgMemory() {
CALLSITE_DELEGATE_SETTER(setOnlyAccessesArgMemory());
}
/// Determine if the function may only access memory that is
/// inaccessible from the IR.
bool onlyAccessesInaccessibleMemory() const {
CALLSITE_DELEGATE_GETTER(onlyAccessesInaccessibleMemory());
}
void setOnlyAccessesInaccessibleMemory() {
CALLSITE_DELEGATE_SETTER(setOnlyAccessesInaccessibleMemory());
}
/// Determine if the function may only access memory that is
/// either inaccessible from the IR or pointed to by its arguments.
bool onlyAccessesInaccessibleMemOrArgMem() const {
CALLSITE_DELEGATE_GETTER(onlyAccessesInaccessibleMemOrArgMem());
}
void setOnlyAccessesInaccessibleMemOrArgMem() {
CALLSITE_DELEGATE_SETTER(setOnlyAccessesInaccessibleMemOrArgMem());
}
/// Determine if the call cannot return.
bool doesNotReturn() const {
CALLSITE_DELEGATE_GETTER(doesNotReturn());
}
void setDoesNotReturn() {
CALLSITE_DELEGATE_SETTER(setDoesNotReturn());
}
/// Determine if the call cannot unwind.
bool doesNotThrow() const {
CALLSITE_DELEGATE_GETTER(doesNotThrow());
}
void setDoesNotThrow() {
CALLSITE_DELEGATE_SETTER(setDoesNotThrow());
}
/// Determine if the call can be duplicated.
bool cannotDuplicate() const {
CALLSITE_DELEGATE_GETTER(cannotDuplicate());
}
void setCannotDuplicate() {
CALLSITE_DELEGATE_SETTER(setCannotDuplicate());
}
/// Determine if the call is convergent.
bool isConvergent() const {
CALLSITE_DELEGATE_GETTER(isConvergent());
}
void setConvergent() {
CALLSITE_DELEGATE_SETTER(setConvergent());
}
void setNotConvergent() {
CALLSITE_DELEGATE_SETTER(setNotConvergent());
}
unsigned getNumOperandBundles() const {
CALLSITE_DELEGATE_GETTER(getNumOperandBundles());
}
bool hasOperandBundles() const {
CALLSITE_DELEGATE_GETTER(hasOperandBundles());
}
unsigned getBundleOperandsStartIndex() const {
CALLSITE_DELEGATE_GETTER(getBundleOperandsStartIndex());
}
unsigned getBundleOperandsEndIndex() const {
CALLSITE_DELEGATE_GETTER(getBundleOperandsEndIndex());
}
unsigned getNumTotalBundleOperands() const {
CALLSITE_DELEGATE_GETTER(getNumTotalBundleOperands());
}
OperandBundleUse getOperandBundleAt(unsigned Index) const {
CALLSITE_DELEGATE_GETTER(getOperandBundleAt(Index));
}
Optional<OperandBundleUse> getOperandBundle(StringRef Name) const {
CALLSITE_DELEGATE_GETTER(getOperandBundle(Name));
}
Optional<OperandBundleUse> getOperandBundle(uint32_t ID) const {
CALLSITE_DELEGATE_GETTER(getOperandBundle(ID));
}
unsigned countOperandBundlesOfType(uint32_t ID) const {
CALLSITE_DELEGATE_GETTER(countOperandBundlesOfType(ID));
}
bool isBundleOperand(unsigned Idx) const {
CALLSITE_DELEGATE_GETTER(isBundleOperand(Idx));
}
IterTy arg_begin() const {
CALLSITE_DELEGATE_GETTER(arg_begin());
}
IterTy arg_end() const {
CALLSITE_DELEGATE_GETTER(arg_end());
}
#undef CALLSITE_DELEGATE_GETTER
#undef CALLSITE_DELEGATE_SETTER
void getOperandBundlesAsDefs(SmallVectorImpl<OperandBundleDef> &Defs) const {
// Since this is actually a getter that "looks like" a setter, don't use the
// above macros to avoid confusion.
cast<CallBase>(getInstruction())->getOperandBundlesAsDefs(Defs);
}
/// Determine whether this data operand is not captured.
bool doesNotCapture(unsigned OpNo) const {
return dataOperandHasImpliedAttr(OpNo + 1, Attribute::NoCapture);
}
/// Determine whether this argument is passed by value.
bool isByValArgument(unsigned ArgNo) const {
return paramHasAttr(ArgNo, Attribute::ByVal);
}
/// Determine whether this argument is passed in an alloca.
bool isInAllocaArgument(unsigned ArgNo) const {
return paramHasAttr(ArgNo, Attribute::InAlloca);
}
/// Determine whether this argument is passed by value or in an alloca.
bool isByValOrInAllocaArgument(unsigned ArgNo) const {
return paramHasAttr(ArgNo, Attribute::ByVal) ||
paramHasAttr(ArgNo, Attribute::InAlloca);
}
/// Determine if there are is an inalloca argument. Only the last argument can
/// have the inalloca attribute.
bool hasInAllocaArgument() const {
return !arg_empty() && paramHasAttr(arg_size() - 1, Attribute::InAlloca);
}
bool doesNotAccessMemory(unsigned OpNo) const {
return dataOperandHasImpliedAttr(OpNo + 1, Attribute::ReadNone);
}
bool onlyReadsMemory(unsigned OpNo) const {
return dataOperandHasImpliedAttr(OpNo + 1, Attribute::ReadOnly) ||
dataOperandHasImpliedAttr(OpNo + 1, Attribute::ReadNone);
}
bool doesNotReadMemory(unsigned OpNo) const {
return dataOperandHasImpliedAttr(OpNo + 1, Attribute::WriteOnly) ||
dataOperandHasImpliedAttr(OpNo + 1, Attribute::ReadNone);
}
/// Return true if the return value is known to be not null.
/// This may be because it has the nonnull attribute, or because at least
/// one byte is dereferenceable and the pointer is in addrspace(0).
bool isReturnNonNull() const {
if (hasRetAttr(Attribute::NonNull))
return true;
else if (getDereferenceableBytes(AttributeList::ReturnIndex) > 0 &&
!NullPointerIsDefined(getCaller(),
getType()->getPointerAddressSpace()))
return true;
return false;
}
/// Returns true if this CallSite passes the given Value* as an argument to
/// the called function.
bool hasArgument(const Value *Arg) const {
for (arg_iterator AI = this->arg_begin(), E = this->arg_end(); AI != E;
++AI)
if (AI->get() == Arg)
return true;
return false;
}
private:
IterTy getCallee() const {
return cast<CallBase>(getInstruction())->op_end() - 1;
}
};
class CallSite : public CallSiteBase<Function, BasicBlock, Value, User, Use,
Instruction, CallInst, InvokeInst,
CallBrInst, User::op_iterator> {
public:
CallSite() = default;
CallSite(CallSiteBase B) : CallSiteBase(B) {}
CallSite(CallInst *CI) : CallSiteBase(CI) {}
CallSite(InvokeInst *II) : CallSiteBase(II) {}
CallSite(CallBrInst *CBI) : CallSiteBase(CBI) {}
explicit CallSite(Instruction *II) : CallSiteBase(II) {}
explicit CallSite(Value *V) : CallSiteBase(V) {}
bool operator==(const CallSite &CS) const { return I == CS.I; }
bool operator!=(const CallSite &CS) const { return I != CS.I; }
bool operator<(const CallSite &CS) const {
return getInstruction() < CS.getInstruction();
}
private:
friend struct DenseMapInfo<CallSite>;
User::op_iterator getCallee() const;
};
/// Establish a view to a call site for examination.
class ImmutableCallSite : public CallSiteBase<> {
public:
ImmutableCallSite() = default;
ImmutableCallSite(const CallInst *CI) : CallSiteBase(CI) {}
ImmutableCallSite(const InvokeInst *II) : CallSiteBase(II) {}
ImmutableCallSite(const CallBrInst *CBI) : CallSiteBase(CBI) {}
explicit ImmutableCallSite(const Instruction *II) : CallSiteBase(II) {}
explicit ImmutableCallSite(const Value *V) : CallSiteBase(V) {}
ImmutableCallSite(CallSite CS) : CallSiteBase(CS.getInstruction()) {}
};
/// AbstractCallSite
///
/// An abstract call site is a wrapper that allows to treat direct,
/// indirect, and callback calls the same. If an abstract call site
/// represents a direct or indirect call site it behaves like a stripped
/// down version of a normal call site object. The abstract call site can
/// also represent a callback call, thus the fact that the initially
/// called function (=broker) may invoke a third one (=callback callee).
/// In this case, the abstract call site hides the middle man, hence the
/// broker function. The result is a representation of the callback call,
/// inside the broker, but in the context of the original call to the broker.
///
/// There are up to three functions involved when we talk about callback call
/// sites. The caller (1), which invokes the broker function. The broker
/// function (2), that will invoke the callee zero or more times. And finally
/// the callee (3), which is the target of the callback call.
///
/// The abstract call site will handle the mapping from parameters to arguments
/// depending on the semantic of the broker function. However, it is important
/// to note that the mapping is often partial. Thus, some arguments of the
/// call/invoke instruction are mapped to parameters of the callee while others
/// are not.
class AbstractCallSite {
public:
/// The encoding of a callback with regards to the underlying instruction.
struct CallbackInfo {
/// For direct/indirect calls the parameter encoding is empty. If it is not,
/// the abstract call site represents a callback. In that case, the first
/// element of the encoding vector represents which argument of the call
/// site CS is the callback callee. The remaining elements map parameters
/// (identified by their position) to the arguments that will be passed
/// through (also identified by position but in the call site instruction).
///
/// NOTE that we use LLVM argument numbers (starting at 0) and not
/// clang/source argument numbers (starting at 1). The -1 entries represent
/// unknown values that are passed to the callee.
using ParameterEncodingTy = SmallVector<int, 0>;
ParameterEncodingTy ParameterEncoding;
};
private:
/// The underlying call site:
/// caller -> callee, if this is a direct or indirect call site
/// caller -> broker function, if this is a callback call site
CallSite CS;
/// The encoding of a callback with regards to the underlying instruction.
CallbackInfo CI;
public:
/// Sole constructor for abstract call sites (ACS).
///
/// An abstract call site can only be constructed through a llvm::Use because
/// each operand (=use) of an instruction could potentially be a different
/// abstract call site. Furthermore, even if the value of the llvm::Use is the
/// same, and the user is as well, the abstract call sites might not be.
///
/// If a use is not associated with an abstract call site the constructed ACS
/// will evaluate to false if converted to a boolean.
///
/// If the use is the callee use of a call or invoke instruction, the
/// constructed abstract call site will behave as a llvm::CallSite would.
///
/// If the use is not a callee use of a call or invoke instruction, the
/// callback metadata is used to determine the argument <-> parameter mapping
/// as well as the callee of the abstract call site.
AbstractCallSite(const Use *U);
/// Add operand uses of \p ICS that represent callback uses into \p CBUses.
///
/// All uses added to \p CBUses can be used to create abstract call sites for
/// which AbstractCallSite::isCallbackCall() will return true.
static void getCallbackUses(ImmutableCallSite ICS,
SmallVectorImpl<const Use *> &CBUses);
/// Conversion operator to conveniently check for a valid/initialized ACS.
explicit operator bool() const { return (bool)CS; }
/// Return the underlying instruction.
Instruction *getInstruction() const { return CS.getInstruction(); }
/// Return the call site abstraction for the underlying instruction.
CallSite getCallSite() const { return CS; }
/// Return true if this ACS represents a direct call.
bool isDirectCall() const {
return !isCallbackCall() && !CS.isIndirectCall();
}
/// Return true if this ACS represents an indirect call.
bool isIndirectCall() const {
return !isCallbackCall() && CS.isIndirectCall();
}
/// Return true if this ACS represents a callback call.
bool isCallbackCall() const {
// For a callback call site the callee is ALWAYS stored first in the
// transitive values vector. Thus, a non-empty vector indicates a callback.
return !CI.ParameterEncoding.empty();
}
/// Return true if @p UI is the use that defines the callee of this ACS.
bool isCallee(Value::const_user_iterator UI) const {
return isCallee(&UI.getUse());
}
/// Return true if @p U is the use that defines the callee of this ACS.
bool isCallee(const Use *U) const {
if (isDirectCall())
return CS.isCallee(U);
assert(!CI.ParameterEncoding.empty() &&
"Callback without parameter encoding!");
return (int)CS.getArgumentNo(U) == CI.ParameterEncoding[0];
}
/// Return the number of parameters of the callee.
unsigned getNumArgOperands() const {
if (isDirectCall())
return CS.getNumArgOperands();
// Subtract 1 for the callee encoding.
return CI.ParameterEncoding.size() - 1;
}
/// Return the operand index of the underlying instruction associated with @p
/// Arg.
int getCallArgOperandNo(Argument &Arg) const {
return getCallArgOperandNo(Arg.getArgNo());
}
/// Return the operand index of the underlying instruction associated with
/// the function parameter number @p ArgNo or -1 if there is none.
int getCallArgOperandNo(unsigned ArgNo) const {
if (isDirectCall())
return ArgNo;
// Add 1 for the callee encoding.
return CI.ParameterEncoding[ArgNo + 1];
}
/// Return the operand of the underlying instruction associated with @p Arg.
Value *getCallArgOperand(Argument &Arg) const {
return getCallArgOperand(Arg.getArgNo());
}
/// Return the operand of the underlying instruction associated with the
/// function parameter number @p ArgNo or nullptr if there is none.
Value *getCallArgOperand(unsigned ArgNo) const {
if (isDirectCall())
return CS.getArgOperand(ArgNo);
// Add 1 for the callee encoding.
return CI.ParameterEncoding[ArgNo + 1] >= 0
? CS.getArgOperand(CI.ParameterEncoding[ArgNo + 1])
: nullptr;
}
/// Return the operand index of the underlying instruction associated with the
/// callee of this ACS. Only valid for callback calls!
int getCallArgOperandNoForCallee() const {
assert(isCallbackCall());
assert(CI.ParameterEncoding.size() && CI.ParameterEncoding[0] >= 0);
return CI.ParameterEncoding[0];
}
/// Return the use of the callee value in the underlying instruction. Only
/// valid for callback calls!
const Use &getCalleeUseForCallback() const {
int CalleeArgIdx = getCallArgOperandNoForCallee();
assert(CalleeArgIdx >= 0 &&
unsigned(CalleeArgIdx) < getInstruction()->getNumOperands());
return getInstruction()->getOperandUse(CalleeArgIdx);
}
/// Return the pointer to function that is being called.
Value *getCalledValue() const {
if (isDirectCall())
return CS.getCalledValue();
return CS.getArgOperand(getCallArgOperandNoForCallee());
}
/// Return the function being called if this is a direct call, otherwise
/// return null (if it's an indirect call).
Function *getCalledFunction() const {
Value *V = getCalledValue();
return V ? dyn_cast<Function>(V->stripPointerCasts()) : nullptr;
}
};
template <> struct DenseMapInfo<CallSite> {
using BaseInfo = DenseMapInfo<decltype(CallSite::I)>;
static CallSite getEmptyKey() {
CallSite CS;
CS.I = BaseInfo::getEmptyKey();
return CS;
}
static CallSite getTombstoneKey() {
CallSite CS;
CS.I = BaseInfo::getTombstoneKey();
return CS;
}
static unsigned getHashValue(const CallSite &CS) {
return BaseInfo::getHashValue(CS.I);
}
static bool isEqual(const CallSite &LHS, const CallSite &RHS) {
return LHS == RHS;
}
};
} // end namespace llvm
#endif // LLVM_IR_CALLSITE_H