[cfe-commits] r131023 - in /cfe/trunk: include/clang/AST/ASTContext.h lib/AST/ASTContext.cpp lib/AST/RecordLayoutBuilder.cpp test/CodeGen/ms_struct-bitfield-3.c

[Fariborz Jahanian]

Author: fjahanian
Date: Fri May  6 16:56:12 2011
New Revision: 131023

URL: http://llvm.org/viewvc/llvm-project?rev=131023&view=rev
Log:
Establish a new alignment for an ms_struct bitfield following
a non-bitfield if size of their types differ.

Added:
    cfe/trunk/test/CodeGen/ms_struct-bitfield-3.c
Modified:
    cfe/trunk/include/clang/AST/ASTContext.h
    cfe/trunk/lib/AST/ASTContext.cpp
    cfe/trunk/lib/AST/RecordLayoutBuilder.cpp

Modified: cfe/trunk/include/clang/AST/ASTContext.h
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/include/clang/AST/ASTContext.h?rev=131023&r1=131022&r2=131023&view=diff
==============================================================================
--- cfe/trunk/include/clang/AST/ASTContext.h (original)
+++ cfe/trunk/include/clang/AST/ASTContext.h Fri May  6 16:56:12 2011
@@ -411,6 +411,16 @@
   /// bitfield which follows the bitfield 'LastFD'.
   bool BitfieldFollowsBitfield(const FieldDecl *FD,
                                    const FieldDecl *LastFD) const;
+  
+  /// NoneBitfieldFollowsBitfield - return 'true" if 'FD' is not a
+  /// bitfield which follows the bitfield 'LastFD'.
+  bool NoneBitfieldFollowsBitfield(const FieldDecl *FD,
+                                   const FieldDecl *LastFD) const;
+  
+  /// BitfieldFollowsNoneBitfield - return 'true" if 'FD' is a
+  /// bitfield which follows the none bitfield 'LastFD'.
+  bool BitfieldFollowsNoneBitfield(const FieldDecl *FD,
+                                   const FieldDecl *LastFD) const;
 
   // Access to the set of methods overridden by the given C++ method.
   typedef CXXMethodVector::iterator overridden_cxx_method_iterator;

Modified: cfe/trunk/lib/AST/ASTContext.cpp
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/lib/AST/ASTContext.cpp?rev=131023&r1=131022&r2=131023&view=diff
==============================================================================
--- cfe/trunk/lib/AST/ASTContext.cpp (original)
+++ cfe/trunk/lib/AST/ASTContext.cpp Fri May  6 16:56:12 2011
@@ -558,6 +558,18 @@
           LastFD->getBitWidth()-> EvaluateAsInt(*this).getZExtValue());  
 }
 
+bool ASTContext::NoneBitfieldFollowsBitfield(const FieldDecl *FD,
+                                         const FieldDecl *LastFD) const {
+  return (!FD->isBitField() && LastFD && LastFD->isBitField() &&
+          LastFD->getBitWidth()-> EvaluateAsInt(*this).getZExtValue());  
+}
+
+bool ASTContext::BitfieldFollowsNoneBitfield(const FieldDecl *FD,
+                                             const FieldDecl *LastFD) const {
+  return (FD->isBitField() && LastFD && !LastFD->isBitField() &&
+          FD->getBitWidth()-> EvaluateAsInt(*this).getZExtValue());  
+}
+
 ASTContext::overridden_cxx_method_iterator
 ASTContext::overridden_methods_begin(const CXXMethodDecl *Method) const {
   llvm::DenseMap<const CXXMethodDecl *, CXXMethodVector>::const_iterator Pos

Modified: cfe/trunk/lib/AST/RecordLayoutBuilder.cpp
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/lib/AST/RecordLayoutBuilder.cpp?rev=131023&r1=131022&r2=131023&view=diff
==============================================================================
--- cfe/trunk/lib/AST/RecordLayoutBuilder.cpp (original)
+++ cfe/trunk/lib/AST/RecordLayoutBuilder.cpp Fri May  6 16:56:12 2011
@@ -1269,12 +1269,15 @@
       // ignored:
       else if (Context.ZeroBitfieldFollowsNonBitfield(FD, LastFD))
         continue;
-      else if (Context.BitfieldFollowsBitfield(FD, LastFD)) {
+      else if (Context.BitfieldFollowsBitfield(FD, LastFD) ||
+               Context.BitfieldFollowsNoneBitfield(FD, LastFD)) {
         // Adjacent bit fields are packed into the same 1-, 2-, or
         // 4-byte allocation unit if the integral types are the same
         // size and if the next bit field fits into the current
         // allocation unit without crossing the boundary imposed by the
         // common alignment requirements of the bit fields.
+        // Also, establish a new alignment for a bitfield following
+        // a non-bitfield if size of their types differ.
         std::pair<uint64_t, unsigned> FieldInfo = 
           Context.getTypeInfo(FD->getType());
         uint64_t TypeSize = FieldInfo.first;

Added: cfe/trunk/test/CodeGen/ms_struct-bitfield-3.c
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/test/CodeGen/ms_struct-bitfield-3.c?rev=131023&view=auto
==============================================================================
--- cfe/trunk/test/CodeGen/ms_struct-bitfield-3.c (added)
+++ cfe/trunk/test/CodeGen/ms_struct-bitfield-3.c Fri May  6 16:56:12 2011
@@ -0,0 +1,24 @@
+// RUN: %clang_cc1 -emit-llvm-only  -triple x86_64-apple-darwin9 %s
+// rdar://8823265
+
+#define ATTR __attribute__((__ms_struct__))
+
+struct _struct_0
+{
+  int  member_0   : 25 ;
+  short  member_1   : 6 ;
+  char  member_2   : 2 ;
+  unsigned  short  member_3   : 1 ;
+  unsigned  char  member_4   : 7 ;
+  short  member_5   : 16 ;
+  int  : 0 ;
+  char  member_7  ;
+
+} ATTR;
+
+typedef struct _struct_0 struct_0;
+
+#define size_struct_0 20
+
+struct_0 test_struct_0 = { 18557917, 17, 3, 0, 80, 6487, 93 };
+static int a[(size_struct_0 == sizeof (struct_0)) -1];