Patch should implement packed enums - PR4098. Credit to Anders Johnsen.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@78471 91177308-0d34-0410-b5e6-96231b3b80d8

diff --git a/include/clang/Parse/Action.h b/include/clang/Parse/Action.h
index 0781a04777b89100bba234fa65f42c45501ac44f..b2be36eb0501f47cbd13d84395e79be12c9406a6 100644 (file)
--- a/include/clang/Parse/Action.h
+++ b/include/clang/Parse/Action.h
@@ -530,7 +530,8 @@ public:
   }
   virtual void ActOnEnumBody(SourceLocation EnumLoc, SourceLocation LBraceLoc,
                              SourceLocation RBraceLoc, DeclPtrTy EnumDecl,
-                             DeclPtrTy *Elements, unsigned NumElements) {}
+                             DeclPtrTy *Elements, unsigned NumElements,
+                             Scope *S, AttributeList *AttrList) {}
 
   //===--------------------------------------------------------------------===//
   // Statement Parsing Callbacks.

diff --git a/lib/Frontend/PrintParserCallbacks.cpp b/lib/Frontend/PrintParserCallbacks.cpp
index 43a5b6f20f11cfe6fdd366679d4fcfa83a530967..c933a2f320dc7682b4fe7e6c65720ac6ebccdef1 100644 (file)
--- a/lib/Frontend/PrintParserCallbacks.cpp
+++ b/lib/Frontend/PrintParserCallbacks.cpp
@@ -245,7 +245,8 @@ namespace {
 
     virtual void ActOnEnumBody(SourceLocation EnumLoc, SourceLocation LBraceLoc,
                                SourceLocation RBraceLoc, DeclPtrTy EnumDecl,
-                               DeclPtrTy *Elements, unsigned NumElements) {
+                               DeclPtrTy *Elements, unsigned NumElements,
+                               Scope *S, AttributeList *AttrList) {
       Out << __FUNCTION__ << "\n";
     }
 

diff --git a/lib/Parse/ParseDecl.cpp b/lib/Parse/ParseDecl.cpp
index a80f57c8ca26fca5f392477a4dbcac7be16996f6..029d9b5aaec7e99b94b83c6ee8e16577a7a1be9f 100644 (file)
--- a/lib/Parse/ParseDecl.cpp
+++ b/lib/Parse/ParseDecl.cpp
@@ -1707,14 +1707,15 @@ void Parser::ParseEnumBody(SourceLocation StartLoc, DeclPtrTy EnumDecl) {
   // Eat the }.
   SourceLocation RBraceLoc = MatchRHSPunctuation(tok::r_brace, LBraceLoc);
 
-  Actions.ActOnEnumBody(StartLoc, LBraceLoc, RBraceLoc, EnumDecl,
-                        EnumConstantDecls.data(), EnumConstantDecls.size());
-  
-  Action::AttrTy *AttrList = 0;
+  AttributeList *Attr = 0;
   // If attributes exist after the identifier list, parse them.
   if (Tok.is(tok::kw___attribute))
-    AttrList = ParseAttributes(); // FIXME: where do they do?
+    Attr = ParseAttributes();
 
+  Actions.ActOnEnumBody(StartLoc, LBraceLoc, RBraceLoc, EnumDecl,
+                        EnumConstantDecls.data(), EnumConstantDecls.size(),
+                        CurScope, Attr);
+  
   EnumScope.Exit();
   Actions.ActOnTagFinishDefinition(CurScope, EnumDecl, RBraceLoc);
 }

diff --git a/lib/Sema/Sema.h b/lib/Sema/Sema.h
index 295607b73995e2e0dcc2e7768b604eaedb42468e..4ad7e704ab589e22a2cee98d3ed4ed2fb21d9cc2 100644 (file)
--- a/lib/Sema/Sema.h
+++ b/lib/Sema/Sema.h
@@ -619,7 +619,8 @@ public:
                                       SourceLocation EqualLoc, ExprTy *Val);
   virtual void ActOnEnumBody(SourceLocation EnumLoc, SourceLocation LBraceLoc,
                              SourceLocation RBraceLoc, DeclPtrTy EnumDecl,
-                             DeclPtrTy *Elements, unsigned NumElements);
+                             DeclPtrTy *Elements, unsigned NumElements,
+                             Scope *S, AttributeList *Attr);
 
   DeclContext *getContainingDC(DeclContext *DC);
 

diff --git a/lib/Sema/SemaDecl.cpp b/lib/Sema/SemaDecl.cpp
index d6b32a72a305c3117ec36676ce31815d84f5c4ba..ed78ec0972db53030cbad780c8f89ec440a323f0 100644 (file)
--- a/lib/Sema/SemaDecl.cpp
+++ b/lib/Sema/SemaDecl.cpp
@@ -5059,14 +5059,20 @@ Sema::DeclPtrTy Sema::ActOnEnumConstant(Scope *S, DeclPtrTy theEnumDecl,
 
 void Sema::ActOnEnumBody(SourceLocation EnumLoc, SourceLocation LBraceLoc,
                          SourceLocation RBraceLoc, DeclPtrTy EnumDeclX,
-                         DeclPtrTy *Elements, unsigned NumElements) {
+                         DeclPtrTy *Elements, unsigned NumElements,
+                         Scope *S, AttributeList *Attr) {
   EnumDecl *Enum = cast<EnumDecl>(EnumDeclX.getAs<Decl>());
   QualType EnumType = Context.getTypeDeclType(Enum);
+
+  if (Attr)
+    ProcessDeclAttributeList(S, Enum, Attr);
   
   // TODO: If the result value doesn't fit in an int, it must be a long or long
   // long value.  ISO C does not support this, but GCC does as an extension,
   // emit a warning.
   unsigned IntWidth = Context.Target.getIntWidth();
+  unsigned CharWidth = Context.Target.getCharWidth();
+  unsigned ShortWidth = Context.Target.getShortWidth();
   
   // Verify that all the values are okay, compute the size of the values, and
   // reverse the list.
@@ -5108,14 +5114,25 @@ void Sema::ActOnEnumBody(SourceLocation EnumLoc, SourceLocation LBraceLoc,
   }
   
   // Figure out the type that should be used for this enum.
-  // FIXME: Support attribute(packed) on enums and -fshort-enums.
+  // FIXME: Support -fshort-enums.
   QualType BestType;
   unsigned BestWidth;
-  
+
+  bool Packed = Enum->getAttr<PackedAttr>() ? true : false;
+
   if (NumNegativeBits) {
     // If there is a negative value, figure out the smallest integer type (of 
     // int/long/longlong) that fits.
-    if (NumNegativeBits <= IntWidth && NumPositiveBits < IntWidth) {
+    // If it's packed, check also if it fits a char or a short.
+    if (Packed && NumNegativeBits <= CharWidth && NumPositiveBits < CharWidth) {
+        BestType = Context.SignedCharTy;
+        BestWidth = CharWidth;
+    } else if (Packed && NumNegativeBits <= ShortWidth && 
+               NumPositiveBits < ShortWidth) {
+        BestType = Context.ShortTy;
+        BestWidth = ShortWidth;
+    }
+    else if (NumNegativeBits <= IntWidth && NumPositiveBits < IntWidth) {
       BestType = Context.IntTy;
       BestWidth = IntWidth;
     } else {
@@ -5134,7 +5151,15 @@ void Sema::ActOnEnumBody(SourceLocation EnumLoc, SourceLocation LBraceLoc,
   } else {
     // If there is no negative value, figure out which of uint, ulong, ulonglong
     // fits.
-    if (NumPositiveBits <= IntWidth) {
+    // If it's packed, check also if it fits a char or a short.
+    if (Packed && NumPositiveBits <= CharWidth) {
+        BestType = Context.UnsignedCharTy;
+        BestWidth = CharWidth;
+    } else if (Packed && NumPositiveBits <= ShortWidth) {
+        BestType = Context.UnsignedShortTy;
+        BestWidth = ShortWidth;
+    }
+    else if (NumPositiveBits <= IntWidth) {
       BestType = Context.UnsignedIntTy;
       BestWidth = IntWidth;
     } else if (NumPositiveBits <=

diff --git a/lib/Sema/SemaTemplateInstantiateDecl.cpp b/lib/Sema/SemaTemplateInstantiateDecl.cpp
index 1c98fca6af4bbe14978cd625953263dfc71ebbb3..86505ee8b0d6fcb514f792f82aa744744025dec9 100644 (file)
--- a/lib/Sema/SemaTemplateInstantiateDecl.cpp
+++ b/lib/Sema/SemaTemplateInstantiateDecl.cpp
@@ -283,9 +283,11 @@ Decl *TemplateDeclInstantiator::VisitEnumDecl(EnumDecl *D) {
   }
       
   // FIXME: Fixup LBraceLoc and RBraceLoc
+  // FIXME: Empty Scope and AttributeList (required to handle attribute packed).
   SemaRef.ActOnEnumBody(Enum->getLocation(), SourceLocation(), SourceLocation(),
                         Sema::DeclPtrTy::make(Enum),
-                        &Enumerators[0], Enumerators.size());
+                        &Enumerators[0], Enumerators.size(),
+                        0, 0);
 
   return Enum;
 }