Overhaul previous-declaration and overload checking to work on lookup results
rather than NamedDecl*. This is a major step towards eliminating
OverloadedFunctionDecl.
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@89263 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Sema/SemaOverload.cpp b/lib/Sema/SemaOverload.cpp
index a86b57c..04bc6b1 100644
--- a/lib/Sema/SemaOverload.cpp
+++ b/lib/Sema/SemaOverload.cpp
@@ -284,100 +284,102 @@
// signature), IsOverload returns false and MatchedDecl will be set to
// point to the FunctionDecl for #2.
bool
-Sema::IsOverload(FunctionDecl *New, Decl* OldD,
- OverloadedFunctionDecl::function_iterator& MatchedDecl) {
- if (OverloadedFunctionDecl* Ovl = dyn_cast<OverloadedFunctionDecl>(OldD)) {
- // Is this new function an overload of every function in the
- // overload set?
- OverloadedFunctionDecl::function_iterator Func = Ovl->function_begin(),
- FuncEnd = Ovl->function_end();
- for (; Func != FuncEnd; ++Func) {
- if (!IsOverload(New, *Func, MatchedDecl)) {
- MatchedDecl = Func;
+Sema::IsOverload(FunctionDecl *New, LookupResult &Previous, NamedDecl *&Match) {
+ for (LookupResult::iterator I = Previous.begin(), E = Previous.end();
+ I != E; ++I) {
+ NamedDecl *Old = (*I)->getUnderlyingDecl();
+ if (FunctionTemplateDecl *OldT = dyn_cast<FunctionTemplateDecl>(Old)) {
+ if (!IsOverload(New, OldT->getTemplatedDecl())) {
+ Match = Old;
return false;
}
- }
-
- // This function overloads every function in the overload set.
- return true;
- } else if (FunctionTemplateDecl *Old = dyn_cast<FunctionTemplateDecl>(OldD))
- return IsOverload(New, Old->getTemplatedDecl(), MatchedDecl);
- else if (FunctionDecl* Old = dyn_cast<FunctionDecl>(OldD)) {
- FunctionTemplateDecl *OldTemplate = Old->getDescribedFunctionTemplate();
- FunctionTemplateDecl *NewTemplate = New->getDescribedFunctionTemplate();
-
- // C++ [temp.fct]p2:
- // A function template can be overloaded with other function templates
- // and with normal (non-template) functions.
- if ((OldTemplate == 0) != (NewTemplate == 0))
- return true;
-
- // Is the function New an overload of the function Old?
- QualType OldQType = Context.getCanonicalType(Old->getType());
- QualType NewQType = Context.getCanonicalType(New->getType());
-
- // Compare the signatures (C++ 1.3.10) of the two functions to
- // determine whether they are overloads. If we find any mismatch
- // in the signature, they are overloads.
-
- // If either of these functions is a K&R-style function (no
- // prototype), then we consider them to have matching signatures.
- if (isa<FunctionNoProtoType>(OldQType.getTypePtr()) ||
- isa<FunctionNoProtoType>(NewQType.getTypePtr()))
+ } else if (FunctionDecl *OldF = dyn_cast<FunctionDecl>(Old)) {
+ if (!IsOverload(New, OldF)) {
+ Match = Old;
+ return false;
+ }
+ } else {
+ // (C++ 13p1):
+ // Only function declarations can be overloaded; object and type
+ // declarations cannot be overloaded.
+ Match = Old;
return false;
-
- FunctionProtoType* OldType = cast<FunctionProtoType>(OldQType);
- FunctionProtoType* NewType = cast<FunctionProtoType>(NewQType);
-
- // The signature of a function includes the types of its
- // parameters (C++ 1.3.10), which includes the presence or absence
- // of the ellipsis; see C++ DR 357).
- if (OldQType != NewQType &&
- (OldType->getNumArgs() != NewType->getNumArgs() ||
- OldType->isVariadic() != NewType->isVariadic() ||
- !std::equal(OldType->arg_type_begin(), OldType->arg_type_end(),
- NewType->arg_type_begin())))
- return true;
-
- // C++ [temp.over.link]p4:
- // The signature of a function template consists of its function
- // signature, its return type and its template parameter list. The names
- // of the template parameters are significant only for establishing the
- // relationship between the template parameters and the rest of the
- // signature.
- //
- // We check the return type and template parameter lists for function
- // templates first; the remaining checks follow.
- if (NewTemplate &&
- (!TemplateParameterListsAreEqual(NewTemplate->getTemplateParameters(),
- OldTemplate->getTemplateParameters(),
- false, TPL_TemplateMatch) ||
- OldType->getResultType() != NewType->getResultType()))
- return true;
-
- // If the function is a class member, its signature includes the
- // cv-qualifiers (if any) on the function itself.
- //
- // As part of this, also check whether one of the member functions
- // is static, in which case they are not overloads (C++
- // 13.1p2). While not part of the definition of the signature,
- // this check is important to determine whether these functions
- // can be overloaded.
- CXXMethodDecl* OldMethod = dyn_cast<CXXMethodDecl>(Old);
- CXXMethodDecl* NewMethod = dyn_cast<CXXMethodDecl>(New);
- if (OldMethod && NewMethod &&
- !OldMethod->isStatic() && !NewMethod->isStatic() &&
- OldMethod->getTypeQualifiers() != NewMethod->getTypeQualifiers())
- return true;
-
- // The signatures match; this is not an overload.
- return false;
- } else {
- // (C++ 13p1):
- // Only function declarations can be overloaded; object and type
- // declarations cannot be overloaded.
- return false;
+ }
}
+
+ return true;
+}
+
+bool Sema::IsOverload(FunctionDecl *New, FunctionDecl *Old) {
+ FunctionTemplateDecl *OldTemplate = Old->getDescribedFunctionTemplate();
+ FunctionTemplateDecl *NewTemplate = New->getDescribedFunctionTemplate();
+
+ // C++ [temp.fct]p2:
+ // A function template can be overloaded with other function templates
+ // and with normal (non-template) functions.
+ if ((OldTemplate == 0) != (NewTemplate == 0))
+ return true;
+
+ // Is the function New an overload of the function Old?
+ QualType OldQType = Context.getCanonicalType(Old->getType());
+ QualType NewQType = Context.getCanonicalType(New->getType());
+
+ // Compare the signatures (C++ 1.3.10) of the two functions to
+ // determine whether they are overloads. If we find any mismatch
+ // in the signature, they are overloads.
+
+ // If either of these functions is a K&R-style function (no
+ // prototype), then we consider them to have matching signatures.
+ if (isa<FunctionNoProtoType>(OldQType.getTypePtr()) ||
+ isa<FunctionNoProtoType>(NewQType.getTypePtr()))
+ return false;
+
+ FunctionProtoType* OldType = cast<FunctionProtoType>(OldQType);
+ FunctionProtoType* NewType = cast<FunctionProtoType>(NewQType);
+
+ // The signature of a function includes the types of its
+ // parameters (C++ 1.3.10), which includes the presence or absence
+ // of the ellipsis; see C++ DR 357).
+ if (OldQType != NewQType &&
+ (OldType->getNumArgs() != NewType->getNumArgs() ||
+ OldType->isVariadic() != NewType->isVariadic() ||
+ !std::equal(OldType->arg_type_begin(), OldType->arg_type_end(),
+ NewType->arg_type_begin())))
+ return true;
+
+ // C++ [temp.over.link]p4:
+ // The signature of a function template consists of its function
+ // signature, its return type and its template parameter list. The names
+ // of the template parameters are significant only for establishing the
+ // relationship between the template parameters and the rest of the
+ // signature.
+ //
+ // We check the return type and template parameter lists for function
+ // templates first; the remaining checks follow.
+ if (NewTemplate &&
+ (!TemplateParameterListsAreEqual(NewTemplate->getTemplateParameters(),
+ OldTemplate->getTemplateParameters(),
+ false, TPL_TemplateMatch) ||
+ OldType->getResultType() != NewType->getResultType()))
+ return true;
+
+ // If the function is a class member, its signature includes the
+ // cv-qualifiers (if any) on the function itself.
+ //
+ // As part of this, also check whether one of the member functions
+ // is static, in which case they are not overloads (C++
+ // 13.1p2). While not part of the definition of the signature,
+ // this check is important to determine whether these functions
+ // can be overloaded.
+ CXXMethodDecl* OldMethod = dyn_cast<CXXMethodDecl>(Old);
+ CXXMethodDecl* NewMethod = dyn_cast<CXXMethodDecl>(New);
+ if (OldMethod && NewMethod &&
+ !OldMethod->isStatic() && !NewMethod->isStatic() &&
+ OldMethod->getTypeQualifiers() != NewMethod->getTypeQualifiers())
+ return true;
+
+ // The signatures match; this is not an overload.
+ return false;
}
/// TryImplicitConversion - Attempt to perform an implicit conversion