Add -fdelayed-template-parsing option. Using this option all templated function definitions are parsed at the end of the translation unit only if it is required by an actual instantiation. As such all the symbols of the TU are available during name lookup.
Using this flag is necessary for compatibility with Microsoft template code.
This also provides some parsing speed improvement.
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@130022 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/AST/Decl.cpp b/lib/AST/Decl.cpp
index 156e017..d37099f 100644
--- a/lib/AST/Decl.cpp
+++ b/lib/AST/Decl.cpp
@@ -1413,7 +1413,7 @@
bool FunctionDecl::hasBody(const FunctionDecl *&Definition) const {
for (redecl_iterator I = redecls_begin(), E = redecls_end(); I != E; ++I) {
- if (I->Body) {
+ if (I->Body || I->IsLateTemplateParsed) {
Definition = *I;
return true;
}
@@ -1427,6 +1427,9 @@
if (I->Body) {
Definition = *I;
return I->Body.get(getASTContext().getExternalSource());
+ } else if (I->IsLateTemplateParsed) {
+ Definition = *I;
+ return 0;
}
}
diff --git a/lib/CodeGen/CodeGenModule.cpp b/lib/CodeGen/CodeGenModule.cpp
index e73a0cf..83e927f 100644
--- a/lib/CodeGen/CodeGenModule.cpp
+++ b/lib/CodeGen/CodeGenModule.cpp
@@ -2031,7 +2031,8 @@
case Decl::CXXMethod:
case Decl::Function:
// Skip function templates
- if (cast<FunctionDecl>(D)->getDescribedFunctionTemplate())
+ if (cast<FunctionDecl>(D)->getDescribedFunctionTemplate() ||
+ cast<FunctionDecl>(D)->isLateTemplateParsed())
return;
EmitGlobal(cast<FunctionDecl>(D));
@@ -2060,12 +2061,15 @@
break;
case Decl::CXXConstructor:
// Skip function templates
- if (cast<FunctionDecl>(D)->getDescribedFunctionTemplate())
+ if (cast<FunctionDecl>(D)->getDescribedFunctionTemplate() ||
+ cast<FunctionDecl>(D)->isLateTemplateParsed())
return;
EmitCXXConstructors(cast<CXXConstructorDecl>(D));
break;
case Decl::CXXDestructor:
+ if (cast<FunctionDecl>(D)->isLateTemplateParsed())
+ return;
EmitCXXDestructors(cast<CXXDestructorDecl>(D));
break;
diff --git a/lib/Driver/Tools.cpp b/lib/Driver/Tools.cpp
index c1f7e15..4e94346 100644
--- a/lib/Driver/Tools.cpp
+++ b/lib/Driver/Tools.cpp
@@ -1605,6 +1605,12 @@
options::OPT_fno_borland_extensions, false))
CmdArgs.push_back("-fborland-extensions");
+ // -fno-delayed-template-parsing is default.
+ if (Args.hasFlag(options::OPT_fdelayed_template_parsing,
+ options::OPT_fno_delayed_template_parsing,
+ false))
+ CmdArgs.push_back("-fdelayed-template-parsing");
+
// -fgnu-keywords default varies depending on language; only pass if
// specified.
if (Arg *A = Args.getLastArg(options::OPT_fgnu_keywords,
diff --git a/lib/Frontend/CompilerInvocation.cpp b/lib/Frontend/CompilerInvocation.cpp
index 5449df2..3f3c1d8 100644
--- a/lib/Frontend/CompilerInvocation.cpp
+++ b/lib/Frontend/CompilerInvocation.cpp
@@ -692,6 +692,8 @@
Res.push_back("-ffake-address-space-map");
if (Opts.ParseUnknownAnytype)
Res.push_back("-funknown-anytype");
+ if (Opts.DelayedTemplateParsing)
+ Res.push_back("-fdelayed-template-parsing");
}
static void PreprocessorOptsToArgs(const PreprocessorOptions &Opts,
@@ -1436,6 +1438,9 @@
if (Args.hasArg(OPT_pthread))
Opts.POSIXThreads = 1;
+ if (Args.hasArg(OPT_fdelayed_template_parsing))
+ Opts.DelayedTemplateParsing = 1;
+
llvm::StringRef Vis = Args.getLastArgValue(OPT_fvisibility, "default");
if (Vis == "default")
Opts.setVisibilityMode(DefaultVisibility);
@@ -1495,6 +1500,7 @@
Opts.MathErrno = Args.hasArg(OPT_fmath_errno);
Opts.InstantiationDepth = Args.getLastArgIntValue(OPT_ftemplate_depth, 1024,
Diags);
+ Opts.DelayedTemplateParsing = Args.hasArg(OPT_fdelayed_template_parsing);
Opts.NumLargeByValueCopy = Args.getLastArgIntValue(OPT_Wlarge_by_value_copy,
0, Diags);
Opts.MSBitfields = Args.hasArg(OPT_mms_bitfields);
diff --git a/lib/Parse/ParseCXXInlineMethods.cpp b/lib/Parse/ParseCXXInlineMethods.cpp
index 93568ef..778aa11 100644
--- a/lib/Parse/ParseCXXInlineMethods.cpp
+++ b/lib/Parse/ParseCXXInlineMethods.cpp
@@ -15,6 +15,7 @@
#include "clang/Parse/Parser.h"
#include "clang/Sema/DeclSpec.h"
#include "clang/Sema/Scope.h"
+#include "clang/AST/DeclTemplate.h"
using namespace clang;
/// ParseCXXInlineMethodDef - We parsed and verified that the specified
@@ -46,6 +47,36 @@
D.complete(FnD);
+ // In delayed template parsing mode, if we are within a class template
+ // or if we are about to parse function member template then consume
+ // the tokens and store them for parsing at the end of the translation unit.
+ if (getLang().DelayedTemplateParsing &&
+ ((Actions.CurContext->isDependentContext() ||
+ TemplateInfo.Kind != ParsedTemplateInfo::NonTemplate) &&
+ !Actions.IsInsideALocalClassWithinATemplateFunction()) &&
+ !D.getDeclSpec().isFriendSpecified()) {
+
+ if (FnD) {
+ LateParsedTemplatedFunction *LPT =
+ new LateParsedTemplatedFunction(this, FnD);
+
+ FunctionDecl *FD = 0;
+ if (FunctionTemplateDecl *FunTmpl = dyn_cast<FunctionTemplateDecl>(FnD))
+ FD = FunTmpl->getTemplatedDecl();
+ else
+ FD = cast<FunctionDecl>(FnD);
+
+ LateParsedTemplateMap[FD] = LPT;
+ Actions.MarkAsLateParsedTemplate(FD);
+ LexTemplateFunctionForLateParsing(LPT->Toks);
+ } else {
+ CachedTokens Toks;
+ LexTemplateFunctionForLateParsing(Toks);
+ }
+
+ return FnD;
+ }
+
// Consume the tokens and store them for later parsing.
LexedMethod* LM = new LexedMethod(this, FnD);
diff --git a/lib/Parse/ParseTemplate.cpp b/lib/Parse/ParseTemplate.cpp
index 84b3788..f21e091 100644
--- a/lib/Parse/ParseTemplate.cpp
+++ b/lib/Parse/ParseTemplate.cpp
@@ -17,6 +17,8 @@
#include "clang/Sema/ParsedTemplate.h"
#include "clang/Sema/Scope.h"
#include "RAIIObjectsForParser.h"
+#include "clang/AST/DeclTemplate.h"
+#include "clang/AST/ASTConsumer.h"
using namespace clang;
/// \brief Parse a template declaration, explicit instantiation, or
@@ -1125,3 +1127,125 @@
R.setBegin(ExternLoc);
return R;
}
+
+void Parser::LateTemplateParserCallback(void *P, FunctionDecl *FD) {
+ ((Parser*)P)->LateTemplateParser(FD);
+}
+
+
+void Parser::LateTemplateParser(FunctionDecl *FD) {
+ LateParsedTemplatedFunction *LPT = LateParsedTemplateMap[FD];
+ if (LPT) {
+ ParseLateTemplatedFuncDef(*LPT);
+ return;
+ }
+
+ llvm_unreachable("Late templated function without associated lexed tokens");
+}
+
+/// \brief Late parse a C++ function template in Microsoft mode.
+void Parser::ParseLateTemplatedFuncDef(LateParsedTemplatedFunction &LMT) {
+ if(!LMT.D)
+ return;
+
+ // If this is a member template, introduce the template parameter scope.
+ ParseScope TemplateScope(this, Scope::TemplateParamScope);
+
+ // Get the FunctionDecl.
+ FunctionDecl *FD = 0;
+ if (FunctionTemplateDecl *FunTmpl = dyn_cast<FunctionTemplateDecl>(LMT.D))
+ FD = FunTmpl->getTemplatedDecl();
+ else
+ FD = cast<FunctionDecl>(LMT.D);
+
+ // Reinject the template parameters.
+ DeclaratorDecl* Declarator = dyn_cast<DeclaratorDecl>(FD);
+ if (Declarator && Declarator->getNumTemplateParameterLists() != 0) {
+ Actions.ActOnReenterDeclaratorTemplateScope(getCurScope(), Declarator);
+ Actions.ActOnReenterTemplateScope(getCurScope(), LMT.D);
+ } else {
+ Actions.ActOnReenterTemplateScope(getCurScope(), LMT.D);
+
+ DeclContext *DD = FD->getLexicalParent();
+ while (DD && DD->isRecord()) {
+ if (ClassTemplatePartialSpecializationDecl* MD =
+ dyn_cast_or_null<ClassTemplatePartialSpecializationDecl>(DD))
+ Actions.ActOnReenterTemplateScope(getCurScope(), MD);
+ else if (CXXRecordDecl* MD = dyn_cast_or_null<CXXRecordDecl>(DD))
+ Actions.ActOnReenterTemplateScope(getCurScope(),
+ MD->getDescribedClassTemplate());
+
+ DD = DD->getLexicalParent();
+ }
+ }
+ assert(!LMT.Toks.empty() && "Empty body!");
+
+ // Append the current token at the end of the new token stream so that it
+ // doesn't get lost.
+ LMT.Toks.push_back(Tok);
+ PP.EnterTokenStream(LMT.Toks.data(), LMT.Toks.size(), true, false);
+
+ // Consume the previously pushed token.
+ ConsumeAnyToken();
+ assert((Tok.is(tok::l_brace) || Tok.is(tok::colon) || Tok.is(tok::kw_try))
+ && "Inline method not starting with '{', ':' or 'try'");
+
+ // Parse the method body. Function body parsing code is similar enough
+ // to be re-used for method bodies as well.
+ ParseScope FnScope(this, Scope::FnScope|Scope::DeclScope);
+
+ // Recreate the DeclContext.
+ Sema::ContextRAII SavedContext(Actions, Actions.getContainingDC(FD));
+
+ if (FunctionTemplateDecl *FunctionTemplate
+ = dyn_cast_or_null<FunctionTemplateDecl>(LMT.D))
+ Actions.ActOnStartOfFunctionDef(getCurScope(),
+ FunctionTemplate->getTemplatedDecl());
+ if (FunctionDecl *Function = dyn_cast_or_null<FunctionDecl>(LMT.D))
+ Actions.ActOnStartOfFunctionDef(getCurScope(), Function);
+
+
+ if (Tok.is(tok::kw_try)) {
+ ParseFunctionTryBlock(LMT.D, FnScope);
+ return;
+ }
+ if (Tok.is(tok::colon)) {
+ ParseConstructorInitializer(LMT.D);
+
+ // Error recovery.
+ if (!Tok.is(tok::l_brace)) {
+ Actions.ActOnFinishFunctionBody(LMT.D, 0);
+ return;
+ }
+ } else
+ Actions.ActOnDefaultCtorInitializers(LMT.D);
+
+ ParseFunctionStatementBody(LMT.D, FnScope);
+ Actions.MarkAsLateParsedTemplate(FD, false);
+
+ DeclGroupPtrTy grp = Actions.ConvertDeclToDeclGroup(LMT.D);
+ if (grp)
+ Actions.getASTConsumer().HandleTopLevelDecl(grp.get());
+}
+
+/// \brief Lex a delayed template function for late parsing.
+void Parser::LexTemplateFunctionForLateParsing(CachedTokens &Toks) {
+ tok::TokenKind kind = Tok.getKind();
+ // We may have a constructor initializer or function-try-block here.
+ if (kind == tok::colon || kind == tok::kw_try)
+ ConsumeAndStoreUntil(tok::l_brace, Toks);
+ else {
+ Toks.push_back(Tok);
+ ConsumeBrace();
+ }
+ // Consume everything up to (and including) the matching right brace.
+ ConsumeAndStoreUntil(tok::r_brace, Toks, /*StopAtSemi=*/false);
+
+ // If we're in a function-try-block, we need to store all the catch blocks.
+ if (kind == tok::kw_try) {
+ while (Tok.is(tok::kw_catch)) {
+ ConsumeAndStoreUntil(tok::l_brace, Toks, /*StopAtSemi=*/false);
+ ConsumeAndStoreUntil(tok::r_brace, Toks, /*StopAtSemi=*/false);
+ }
+ }
+}
diff --git a/lib/Parse/Parser.cpp b/lib/Parse/Parser.cpp
index 492b8f5..6522306 100644
--- a/lib/Parse/Parser.cpp
+++ b/lib/Parse/Parser.cpp
@@ -19,6 +19,7 @@
#include "llvm/Support/raw_ostream.h"
#include "RAIIObjectsForParser.h"
#include "ParsePragma.h"
+#include "clang/AST/DeclTemplate.h"
using namespace clang;
Parser::Parser(Preprocessor &pp, Sema &actions)
@@ -362,6 +363,11 @@
for (unsigned i = 0, e = NumCachedScopes; i != e; ++i)
delete ScopeCache[i];
+ // Free LateParsedTemplatedFunction nodes.
+ for (LateParsedTemplateMapT::iterator it = LateParsedTemplateMap.begin();
+ it != LateParsedTemplateMap.end(); ++it)
+ delete it->second;
+
// Remove the pragma handlers we installed.
PP.RemovePragmaHandler(AlignHandler.get());
AlignHandler.reset();
@@ -438,6 +444,10 @@
Result = DeclGroupPtrTy();
if (Tok.is(tok::eof)) {
+ // Late template parsing can begin.
+ if (getLang().DelayedTemplateParsing)
+ Actions.SetLateTemplateParser(LateTemplateParserCallback, this);
+
Actions.ActOnEndOfTranslationUnit();
return true;
}
@@ -786,6 +796,43 @@
return 0;
}
+ // In delayed template parsing mode, for function template we consume the
+ // tokens and store them for late parsing at the end of the translation unit.
+ if (getLang().DelayedTemplateParsing &&
+ TemplateInfo.Kind == ParsedTemplateInfo::Template) {
+ MultiTemplateParamsArg TemplateParameterLists(Actions,
+ TemplateInfo.TemplateParams->data(),
+ TemplateInfo.TemplateParams->size());
+
+ ParseScope BodyScope(this, Scope::FnScope|Scope::DeclScope);
+ Scope *ParentScope = getCurScope()->getParent();
+
+ Decl *DP = Actions.HandleDeclarator(ParentScope, D,
+ move(TemplateParameterLists),
+ /*IsFunctionDefinition=*/true);
+ D.complete(DP);
+ D.getMutableDeclSpec().abort();
+
+ if (DP) {
+ LateParsedTemplatedFunction *LPT = new LateParsedTemplatedFunction(this, DP);
+
+ FunctionDecl *FnD = 0;
+ if (FunctionTemplateDecl *FunTmpl = dyn_cast<FunctionTemplateDecl>(DP))
+ FnD = FunTmpl->getTemplatedDecl();
+ else
+ FnD = cast<FunctionDecl>(DP);
+
+ LateParsedTemplateMap[FnD] = LPT;
+ Actions.MarkAsLateParsedTemplate(FnD);
+ LexTemplateFunctionForLateParsing(LPT->Toks);
+ } else {
+ CachedTokens Toks;
+ LexTemplateFunctionForLateParsing(Toks);
+ }
+ return DP;
+ }
+
+
// Enter a scope for the function body.
ParseScope BodyScope(this, Scope::FnScope|Scope::DeclScope);
diff --git a/lib/Sema/Sema.cpp b/lib/Sema/Sema.cpp
index 403cf62..dc12702 100644
--- a/lib/Sema/Sema.cpp
+++ b/lib/Sema/Sema.cpp
@@ -142,6 +142,7 @@
Diags(PP.getDiagnostics()), SourceMgr(PP.getSourceManager()),
ExternalSource(0), CodeCompleter(CodeCompleter), CurContext(0),
PackContext(0), VisContext(0),
+ LateTemplateParser(0), OpaqueParser(0),
IdResolver(pp.getLangOptions()), CXXTypeInfoDecl(0), MSVCGuidDecl(0),
GlobalNewDeleteDeclared(false),
CompleteTranslationUnit(CompleteTranslationUnit),
diff --git a/lib/Sema/SemaDecl.cpp b/lib/Sema/SemaDecl.cpp
index e506dd5..2abc6da 100644
--- a/lib/Sema/SemaDecl.cpp
+++ b/lib/Sema/SemaDecl.cpp
@@ -5748,8 +5748,13 @@
// See if this is a redefinition.
// But don't complain if we're in GNU89 mode and the previous definition
// was an extern inline function.
+
+ // FIXME: This code doesn't complain about multiple definition for late
+ // parsed template function.
+ bool IsLateParsingRedefinition = LateTemplateParser &&
+ FD->isLateTemplateParsed();
const FunctionDecl *Definition;
- if (FD->hasBody(Definition) &&
+ if (FD->hasBody(Definition) && !IsLateParsingRedefinition &&
!canRedefineFunction(Definition, getLangOptions())) {
if (getLangOptions().GNUMode && Definition->isInlineSpecified() &&
Definition->getStorageClass() == SC_Extern)
diff --git a/lib/Sema/SemaDeclCXX.cpp b/lib/Sema/SemaDeclCXX.cpp
index 53a7c73..5f3f600 100644
--- a/lib/Sema/SemaDeclCXX.cpp
+++ b/lib/Sema/SemaDeclCXX.cpp
@@ -3166,6 +3166,25 @@
}
}
+void Sema::ActOnReenterDeclaratorTemplateScope(Scope *S, DeclaratorDecl *D) {
+ if (!D)
+ return;
+
+ int NumParamList = D->getNumTemplateParameterLists();
+ for (int i = 0; i < NumParamList; i++) {
+ TemplateParameterList* Params = D->getTemplateParameterList(i);
+ for (TemplateParameterList::iterator Param = Params->begin(),
+ ParamEnd = Params->end();
+ Param != ParamEnd; ++Param) {
+ NamedDecl *Named = cast<NamedDecl>(*Param);
+ if (Named->getDeclName()) {
+ S->AddDecl(Named);
+ IdResolver.AddDecl(Named);
+ }
+ }
+ }
+}
+
void Sema::ActOnReenterTemplateScope(Scope *S, Decl *D) {
if (!D)
return;
diff --git a/lib/Sema/SemaTemplate.cpp b/lib/Sema/SemaTemplate.cpp
index 49e4a87..08eb654 100644
--- a/lib/Sema/SemaTemplate.cpp
+++ b/lib/Sema/SemaTemplate.cpp
@@ -6381,3 +6381,24 @@
Out << ']';
return Out.str();
}
+
+void Sema::MarkAsLateParsedTemplate(FunctionDecl *FD, bool Flag) {
+ if (!FD)
+ return;
+ FD->setLateTemplateParsed(Flag);
+}
+
+bool Sema::IsInsideALocalClassWithinATemplateFunction() {
+ DeclContext *DC = CurContext;
+
+ while (DC) {
+ if (CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(CurContext)) {
+ const FunctionDecl *FD = RD->isLocalClass();
+ return (FD && FD->getTemplatedKind() != FunctionDecl::TK_NonTemplate);
+ } else if (DC->isTranslationUnit() || DC->isNamespace())
+ return false;
+
+ DC = DC->getParent();
+ }
+ return false;
+}
diff --git a/lib/Sema/SemaTemplateInstantiateDecl.cpp b/lib/Sema/SemaTemplateInstantiateDecl.cpp
index 0ff7ff4..588501f 100644
--- a/lib/Sema/SemaTemplateInstantiateDecl.cpp
+++ b/lib/Sema/SemaTemplateInstantiateDecl.cpp
@@ -2262,6 +2262,21 @@
if (PatternDecl)
Pattern = PatternDecl->getBody(PatternDecl);
+ // Postpone late parsed template instantiations.
+ if (PatternDecl->isLateTemplateParsed() && !LateTemplateParser) {
+ PendingInstantiations.push_back(
+ std::make_pair(Function, PointOfInstantiation));
+ return;
+ }
+
+ // Call the LateTemplateParser callback if there a need to late parse
+ // a templated function definition.
+ if (!Pattern && PatternDecl && PatternDecl->isLateTemplateParsed() &&
+ LateTemplateParser) {
+ LateTemplateParser(OpaqueParser, (FunctionDecl*)PatternDecl);
+ Pattern = PatternDecl->getBody(PatternDecl);
+ }
+
if (!Pattern) {
if (DefinitionRequired) {
if (Function->getPrimaryTemplate())