blob: eb2604c6252ddc6c884cf636f3d31cdcba25d0cd [file] [log] [blame]
//===- LowLevelHelpers.cpp -------------------------------------*- 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
//
//===----------------------------------------------------------------------===//
#include "clang/ASTMatchers/LowLevelHelpers.h"
#include "clang/AST/Decl.h"
#include "clang/AST/DeclCXX.h"
#include "clang/AST/Expr.h"
#include "clang/AST/ExprCXX.h"
#include <type_traits>
namespace clang {
namespace ast_matchers {
static const FunctionDecl *getCallee(const CXXConstructExpr &D) {
return D.getConstructor();
}
static const FunctionDecl *getCallee(const CallExpr &D) {
return D.getDirectCallee();
}
template <class ExprNode>
static void matchEachArgumentWithParamTypeImpl(
const ExprNode &Node,
llvm::function_ref<void(QualType /*Param*/, const Expr * /*Arg*/)>
OnParamAndArg) {
static_assert(std::is_same_v<CallExpr, ExprNode> ||
std::is_same_v<CXXConstructExpr, ExprNode>);
// The first argument of an overloaded member operator is the implicit object
// argument of the method which should not be matched against a parameter, so
// we skip over it here.
unsigned ArgIndex = 0;
if (const auto *CE = dyn_cast<CXXOperatorCallExpr>(&Node)) {
const auto *MD = dyn_cast_or_null<CXXMethodDecl>(CE->getDirectCallee());
if (MD && !MD->isExplicitObjectMemberFunction()) {
// This is an overloaded operator call.
// We need to skip the first argument, which is the implicit object
// argument of the method which should not be matched against a
// parameter.
++ArgIndex;
}
}
const FunctionProtoType *FProto = nullptr;
if (const auto *Call = dyn_cast<CallExpr>(&Node)) {
if (const auto *Value =
dyn_cast_or_null<ValueDecl>(Call->getCalleeDecl())) {
QualType QT = Value->getType().getCanonicalType();
// This does not necessarily lead to a `FunctionProtoType`,
// e.g. K&R functions do not have a function prototype.
if (QT->isFunctionPointerType())
FProto = QT->getPointeeType()->getAs<FunctionProtoType>();
if (QT->isMemberFunctionPointerType()) {
const auto *MP = QT->getAs<MemberPointerType>();
assert(MP && "Must be member-pointer if its a memberfunctionpointer");
FProto = MP->getPointeeType()->getAs<FunctionProtoType>();
assert(FProto &&
"The call must have happened through a member function "
"pointer");
}
}
}
unsigned ParamIndex = 0;
unsigned NumArgs = Node.getNumArgs();
if (FProto && FProto->isVariadic())
NumArgs = std::min(NumArgs, FProto->getNumParams());
for (; ArgIndex < NumArgs; ++ArgIndex, ++ParamIndex) {
QualType ParamType;
if (FProto && FProto->getNumParams() > ParamIndex)
ParamType = FProto->getParamType(ParamIndex);
else if (const FunctionDecl *FD = getCallee(Node);
FD && FD->getNumParams() > ParamIndex)
ParamType = FD->getParamDecl(ParamIndex)->getType();
else
continue;
OnParamAndArg(ParamType, Node.getArg(ArgIndex)->IgnoreParenCasts());
}
}
void matchEachArgumentWithParamType(
const CallExpr &Node,
llvm::function_ref<void(QualType /*Param*/, const Expr * /*Arg*/)>
OnParamAndArg) {
matchEachArgumentWithParamTypeImpl(Node, OnParamAndArg);
}
void matchEachArgumentWithParamType(
const CXXConstructExpr &Node,
llvm::function_ref<void(QualType /*Param*/, const Expr * /*Arg*/)>
OnParamAndArg) {
matchEachArgumentWithParamTypeImpl(Node, OnParamAndArg);
}
} // namespace ast_matchers
} // namespace clang