[clang] abbd57e - Factor out and centralize repeated 'getExpandedPackSize'.

[Richard Smith via cfe-commits]

Author: Richard Smith
Date: 2020-12-13T22:43:23-08:00
New Revision: abbd57e558b907a7be8adc5a5b9699dd7c23b1af

URL: https://github.com/llvm/llvm-project/commit/abbd57e558b907a7be8adc5a5b9699dd7c23b1af
DIFF: https://github.com/llvm/llvm-project/commit/abbd57e558b907a7be8adc5a5b9699dd7c23b1af.diff

LOG: Factor out and centralize repeated 'getExpandedPackSize'.

Added: 
    

Modified: 
    clang/include/clang/AST/DeclTemplate.h
    clang/lib/AST/DeclTemplate.cpp
    clang/lib/Sema/SemaTemplate.cpp
    clang/lib/Sema/SemaTemplateDeduction.cpp

Removed: 
    


################################################################################
diff  --git a/clang/include/clang/AST/DeclTemplate.h b/clang/include/clang/AST/DeclTemplate.h
index 641647659c17..7fbf6294970e 100644
--- a/clang/include/clang/AST/DeclTemplate.h
+++ b/clang/include/clang/AST/DeclTemplate.h
@@ -3353,6 +3353,36 @@ inline TemplateDecl *getAsTypeTemplateDecl(Decl *D) {
              : nullptr;
 }
 
+/// Check whether the template parameter is a pack expansion, and if so,
+/// determine the number of parameters produced by that expansion. For instance:
+///
+/// \code
+/// template<typename ...Ts> struct A {
+///   template<Ts ...NTs, template<Ts> class ...TTs, typename ...Us> struct B;
+/// };
+/// \endcode
+///
+/// In \c A<int,int>::B, \c NTs and \c TTs have expanded pack size 2, and \c Us
+/// is not a pack expansion, so returns an empty Optional.
+inline Optional<unsigned> getExpandedPackSize(const NamedDecl *Param) {
+  if (const auto *TTP = dyn_cast<TemplateTypeParmDecl>(Param)) {
+    if (TTP->isExpandedParameterPack())
+      return TTP->getNumExpansionParameters();
+  }
+
+  if (const auto *NTTP = dyn_cast<NonTypeTemplateParmDecl>(Param)) {
+    if (NTTP->isExpandedParameterPack())
+      return NTTP->getNumExpansionTypes();
+  }
+
+  if (const auto *TTP = dyn_cast<TemplateTemplateParmDecl>(Param)) {
+    if (TTP->isExpandedParameterPack())
+      return TTP->getNumExpansionTemplateParameters();
+  }
+
+  return None;
+}
+
 } // namespace clang
 
 #endif // LLVM_CLANG_AST_DECLTEMPLATE_H

diff  --git a/clang/lib/AST/DeclTemplate.cpp b/clang/lib/AST/DeclTemplate.cpp
index 328ceaa63df3..25235c56ec46 100644
--- a/clang/lib/AST/DeclTemplate.cpp
+++ b/clang/lib/AST/DeclTemplate.cpp
@@ -102,24 +102,10 @@ unsigned TemplateParameterList::getMinRequiredArguments() const {
   unsigned NumRequiredArgs = 0;
   for (const NamedDecl *P : asArray()) {
     if (P->isTemplateParameterPack()) {
-      if (const auto *NTTP = dyn_cast<NonTypeTemplateParmDecl>(P)) {
-        if (NTTP->isExpandedParameterPack()) {
-          NumRequiredArgs += NTTP->getNumExpansionTypes();
-          continue;
-        }
-      } else if (const auto *TTP = dyn_cast<TemplateTypeParmDecl>(P)) {
-        if (TTP->isExpandedParameterPack()) {
-          NumRequiredArgs += TTP->getNumExpansionParameters();
-          continue;
-        }
-      } else {
-        const auto *TP = cast<TemplateTemplateParmDecl>(P);
-        if (TP->isExpandedParameterPack()) {
-          NumRequiredArgs += TP->getNumExpansionTemplateParameters();
-          continue;
-        }
+      if (Optional<unsigned> Expansions = getExpandedPackSize(P)) {
+        NumRequiredArgs += *Expansions;
+        continue;
       }
-
       break;
     }
 

diff  --git a/clang/lib/Sema/SemaTemplate.cpp b/clang/lib/Sema/SemaTemplate.cpp
index 4176aa1f458f..70a25fb782e9 100644
--- a/clang/lib/Sema/SemaTemplate.cpp
+++ b/clang/lib/Sema/SemaTemplate.cpp
@@ -5588,39 +5588,6 @@ bool Sema::CheckTemplateArgument(NamedDecl *Param,
   return false;
 }
 
-/// Check whether the template parameter is a pack expansion, and if so,
-/// determine the number of parameters produced by that expansion. For instance:
-///
-/// \code
-/// template<typename ...Ts> struct A {
-///   template<Ts ...NTs, template<Ts> class ...TTs, typename ...Us> struct B;
-/// };
-/// \endcode
-///
-/// In \c A<int,int>::B, \c NTs and \c TTs have expanded pack size 2, and \c Us
-/// is not a pack expansion, so returns an empty Optional.
-static Optional<unsigned> getExpandedPackSize(NamedDecl *Param) {
-  if (TemplateTypeParmDecl *TTP
-        = dyn_cast<TemplateTypeParmDecl>(Param)) {
-    if (TTP->isExpandedParameterPack())
-      return TTP->getNumExpansionParameters();
-  }
-
-  if (NonTypeTemplateParmDecl *NTTP
-        = dyn_cast<NonTypeTemplateParmDecl>(Param)) {
-    if (NTTP->isExpandedParameterPack())
-      return NTTP->getNumExpansionTypes();
-  }
-
-  if (TemplateTemplateParmDecl *TTP
-        = dyn_cast<TemplateTemplateParmDecl>(Param)) {
-    if (TTP->isExpandedParameterPack())
-      return TTP->getNumExpansionTemplateParameters();
-  }
-
-  return None;
-}
-
 /// Diagnose a missing template argument.
 template<typename TemplateParmDecl>
 static bool diagnoseMissingArgument(Sema &S, SourceLocation Loc,

diff  --git a/clang/lib/Sema/SemaTemplateDeduction.cpp b/clang/lib/Sema/SemaTemplateDeduction.cpp
index d137aec82b8c..4a3b64cf5425 100644
--- a/clang/lib/Sema/SemaTemplateDeduction.cpp
+++ b/clang/lib/Sema/SemaTemplateDeduction.cpp
@@ -658,23 +658,6 @@ static TemplateParameter makeTemplateParameter(Decl *D) {
   return TemplateParameter(cast<TemplateTemplateParmDecl>(D));
 }
 
-/// If \p Param is an expanded parameter pack, get the number of expansions.
-static Optional<unsigned> getExpandedPackSize(NamedDecl *Param) {
-  if (auto *TTP = dyn_cast<TemplateTypeParmDecl>(Param))
-    if (TTP->isExpandedParameterPack())
-      return TTP->getNumExpansionParameters();
-
-  if (auto *NTTP = dyn_cast<NonTypeTemplateParmDecl>(Param))
-    if (NTTP->isExpandedParameterPack())
-      return NTTP->getNumExpansionTypes();
-
-  if (auto *TTP = dyn_cast<TemplateTemplateParmDecl>(Param))
-    if (TTP->isExpandedParameterPack())
-      return TTP->getNumExpansionTemplateParameters();
-
-  return None;
-}
-
 /// A pack that we're currently deducing.
 struct clang::DeducedPack {
   // The index of the pack.