[0.2.x] fixed : issue #11761 ( signed bit fields is not supported )

git-svn-id: https://pykd.svn.codeplex.com/svn@83601 9b283d60-5439-405e-af05-b73fd8c4d996

pykd/typedvar.cpp

@@ -432,6 +432,40 @@ BaseTypeVariant BitFieldVar::getValue()
 
     m_varData->read( &val, getSize() );
 
+    if ( m_typeInfo->isSigned() )
+    {
+        ULONG width = m_typeInfo->getBitWidth();
+
+        val >>= m_typeInfo->getBitOffset();
+
+        if ( ( val & ( 1ULL << ( width -1 ) ) ) != 0 )
+        {
+            val |= ~( ( 1ULL << width ) - 1 );
+        }
+        else
+        {
+            val &= ( 1ULL << width ) - 1;
+        }
+
+        LONG64     signedVal = (LONG64)val;
+        
+        switch ( m_typeInfo->getSize() )
+        {
+        case 1:
+            return (LONG)signedVal;
+
+        case 2:
+            return (LONG)signedVal;
+
+        case 4:
+            return (LONG)signedVal;
+
+        case 8:
+            return signedVal;
+        }
+    }
+    else
+    {
         val >>= m_typeInfo->getBitOffset();
         val &= ( 1 << m_typeInfo->getBitWidth() ) - 1;
 
@@ -449,6 +483,8 @@ BaseTypeVariant BitFieldVar::getValue()
         case 8:
             return *(PULONG64)&val;
         }
+    }
+
 
     throw DbgException( "failed get value " );
 }

pykd/typeinfo.cpp

@@ -351,6 +351,7 @@ BitFieldTypeInfo::BitFieldTypeInfo( SymbolPtr &symbol )
     TypeInfoPtr    typeInfo = TypeInfo::getBaseTypeInfo( symbol->getType() );
 
     m_size = (ULONG)typeInfo->getSize();
+    m_signed = typeInfo->isSigned();
 
     std::stringstream   sstr;
 

pykd/typeinfo.h

@@ -171,6 +171,10 @@ public:
         return false;
     }
 
+    virtual bool isSigned() {
+        throw TypeException( getName(), "type is not based" );
+    }
+
     virtual ULONG getCount() {
         throw TypeException( getName(), "type is not an array" );
     }
@@ -276,10 +280,19 @@ private:
         return true;
     }
 
-    std::string     m_name;
+    virtual bool isSigned() {
+        T t = static_cast<T>(-1);
+        return t < 0;
+    }
 
+    std::string     m_name;
 };
 
+template<>
+bool TypeInfoWrapper<bool>::isSigned() {
+    return false;
+}
+
 ///////////////////////////////////////////////////////////////////////////////////
 
 class BitFieldTypeInfo : public TypeInfo
@@ -312,8 +325,13 @@ public:
         return m_size;
     }
 
+    virtual bool isSigned() {
+        return m_signed;
+    }
+
 private:
 
+    bool            m_signed;
     ULONG           m_size;
     ULONG           m_bitWidth;
     ULONG           m_bitPos;

test/scripts/typedvar.py

@@ -140,11 +140,11 @@ class TypedVarTest( unittest.TestCase ):
         tv = target.module.typedVar("g_structWithBits")
         self.assertEqual( 4, tv.m_bit0_4 )
         self.assertEqual( 1, tv.m_bit5 )
-        self.assertEqual( 3, tv.m_bit6_7 )
+        self.assertEqual( 5, tv.m_bit6_8 )
         tv = target.module.typedVar("g_structWithSignBits")
         self.assertEqual( 4, tv.m_bit0_4 )
         self.assertEqual( -1, tv.m_bit5 )
-        self.assertEqual( -1, tv.m_bit6_7 )
+        self.assertEqual( -3, tv.m_bit6_8 )
 
     def testTypedVarList(self):
         tvl = target.module.typedVarList( target.module.g_listHead, "listStruct", "listEntry" )

test/targetapp/targetapp.cpp

@@ -44,13 +44,13 @@ std::string g_string;
 struct structWithBits {
     ULONG m_bit0_4  : 5;
     ULONG m_bit5    : 1;
-    ULONG m_bit6_7  : 2;
+    ULONG m_bit6_8  : 3;
 };
 
 struct structWitSignBits {
     LONG m_bit0_4  : 5;
     LONG m_bit5    : 1;
-    LONG m_bit6_7  : 2;
+    LONG m_bit6_8  : 3;
 };
 
 
@@ -104,8 +104,8 @@ typedef struct structAbstract  *pstructAbstract;
 
 pstructAbstract g_structAbstract = 0;
 
-structWithBits g_structWithBits = { 4, 1, 3};
+structWithBits g_structWithBits = { 4, 1, 5};
-structWitSignBits g_structWithSignBits = { 4, 1, 3 };
+structWitSignBits g_structWithSignBits = { 4, 1, 5 };
 
 structTest      g_structTest = { 0, 500, true, 1, NULL };
 structTest      g_structTest1 = { 0, 500, true, 1, &g_structTest };