unroll code for early returns, no logic changed intended

Change-Id: Ic1cc63a5fe3ad2c949f91c395c00f5f99bd7602a

vcl/headless/svpbmp.cxx

@@ -53,97 +53,95 @@ BitmapBuffer* ImplCreateDIB(
         || nBitCount == 32)
         && "Unsupported BitCount!");
 
+    if (!rSize.Width() || !rSize.Height())
+        return nullptr;
+
     BitmapBuffer* pDIB = nullptr;
 
-    if( rSize.Width() && rSize.Height() )
+    try
     {
-        try
-        {
-            pDIB = new BitmapBuffer;
-        }
-        catch (const std::bad_alloc&)
-        {
-            pDIB = nullptr;
-        }
+        pDIB = new BitmapBuffer;
+    }
+    catch (const std::bad_alloc&)
+    {
+        pDIB = nullptr;
+    }
 
-        if( pDIB )
+    if(!pDIB)
+        return nullptr;
+
+    const sal_uInt16 nColors = ( nBitCount <= 8 ) ? ( 1 << nBitCount ) : 0;
+
+    switch (nBitCount)
+    {
+        case 1:
+            pDIB->mnFormat = ScanlineFormat::N1BitLsbPal;
+            break;
+        case 4:
+            pDIB->mnFormat = ScanlineFormat::N4BitMsnPal;
+            break;
+        case 8:
+            pDIB->mnFormat = ScanlineFormat::N8BitPal;
+            break;
+        case 16:
         {
-            const sal_uInt16 nColors = ( nBitCount <= 8 ) ? ( 1 << nBitCount ) : 0;
-
-            switch (nBitCount)
-            {
-                case 1:
-                    pDIB->mnFormat = ScanlineFormat::N1BitLsbPal;
-                    break;
-                case 4:
-                    pDIB->mnFormat = ScanlineFormat::N4BitMsnPal;
-                    break;
-                case 8:
-                    pDIB->mnFormat = ScanlineFormat::N8BitPal;
-                    break;
-                case 16:
-                {
 #ifdef OSL_BIGENDIAN
-                    pDIB->mnFormat= ScanlineFormat::N16BitTcMsbMask;
+            pDIB->mnFormat= ScanlineFormat::N16BitTcMsbMask;
 #else
-                    pDIB->mnFormat= ScanlineFormat::N16BitTcLsbMask;
+            pDIB->mnFormat= ScanlineFormat::N16BitTcLsbMask;
 #endif
-                    ColorMaskElement aRedMask(0xf800);
-                    aRedMask.CalcMaskShift();
-                    ColorMaskElement aGreenMask(0x07e0);
-                    aGreenMask.CalcMaskShift();
-                    ColorMaskElement aBlueMask(0x001f);
-                    aBlueMask.CalcMaskShift();
-                    pDIB->maColorMask = ColorMask(aRedMask, aGreenMask, aBlueMask);
-                    break;
-                }
-                default:
-                    nBitCount = 32;
-                    SAL_FALLTHROUGH;
-                case 32:
-                {
-                    pDIB->mnFormat = SVP_CAIRO_FORMAT;
-                    break;
-                }
-            }
-
-            pDIB->mnFormat |= ScanlineFormat::TopDown;
-            pDIB->mnWidth = rSize.Width();
-            pDIB->mnHeight = rSize.Height();
-            pDIB->mnScanlineSize = AlignedWidth4Bytes( pDIB->mnWidth * nBitCount );
-            pDIB->mnBitCount = nBitCount;
-
-            if( nColors )
-            {
-                pDIB->maPalette = rPal;
-                pDIB->maPalette.SetEntryCount( nColors );
-            }
-
-            try
-            {
-                size_t size = pDIB->mnScanlineSize * pDIB->mnHeight;
-                pDIB->mpBits = new sal_uInt8[size];
+            ColorMaskElement aRedMask(0xf800);
+            aRedMask.CalcMaskShift();
+            ColorMaskElement aGreenMask(0x07e0);
+            aGreenMask.CalcMaskShift();
+            ColorMaskElement aBlueMask(0x001f);
+            aBlueMask.CalcMaskShift();
+            pDIB->maColorMask = ColorMask(aRedMask, aGreenMask, aBlueMask);
+            break;
+        }
+        default:
+            nBitCount = 32;
+            SAL_FALLTHROUGH;
+        case 32:
+        {
+            pDIB->mnFormat = SVP_CAIRO_FORMAT;
+            break;
+        }
+    }
+
+    pDIB->mnFormat |= ScanlineFormat::TopDown;
+    pDIB->mnWidth = rSize.Width();
+    pDIB->mnHeight = rSize.Height();
+    pDIB->mnScanlineSize = AlignedWidth4Bytes( pDIB->mnWidth * nBitCount );
+    pDIB->mnBitCount = nBitCount;
+
+    if( nColors )
+    {
+        pDIB->maPalette = rPal;
+        pDIB->maPalette.SetEntryCount( nColors );
+    }
+
+    try
+    {
+        size_t size = pDIB->mnScanlineSize * pDIB->mnHeight;
+        pDIB->mpBits = new sal_uInt8[size];
 #ifdef __SANITIZE_ADDRESS__
-                if (!pDIB->mpBits)
-                {   // can only happen with ASAN allocator_may_return_null=1
-                    delete pDIB;
-                    pDIB = nullptr;
-                }
-                else
+        if (!pDIB->mpBits)
+        {   // can only happen with ASAN allocator_may_return_null=1
+            delete pDIB;
+            pDIB = nullptr;
+        }
+        else
 #endif
-                {
-                    std::memset(pDIB->mpBits, 0, size);
-                }
-            }
-            catch (const std::bad_alloc&)
-            {
-                delete pDIB;
-                pDIB = nullptr;
-            }
+        {
+            std::memset(pDIB->mpBits, 0, size);
         }
     }
-    else
+    catch (const std::bad_alloc&)
+    {
+        delete pDIB;
         pDIB = nullptr;
+    }
 
     return pDIB;
 }