limit symbols exported when using --enable-mergelibs

when doing LTO and --enable-mergelibs, we can improve the effectiveness
of LTO by marking more code as internal to the merged library.

So introduce a new macro UNLESS_MERGELIBS, which we can wrap around
*_DLLPUBLIC annotations

Also introduced here is a script that can be run on a completed build to
determine which classes can be marked with this macro.

Change-Id: I73fb87c897489da53791277d0b66b01f884ba061
Reviewed-on: https://gerrit.libreoffice.org/c/core/+/89991
Tested-by: Jenkins
Reviewed-by: Noel Grandin <noel.grandin@collabora.co.uk>

2 files changed, 600 insertions, 0 deletions

diff --git a/bin/find-mergedlib-can-be-private.classes.results b/bin/find-mergedlib-can-be-private.classes.results
new file mode 100644
index 000000000000..0d8f9b808e15
--- /dev/null
+++ b/bin/find-mergedlib-can-be-private.classes.results
@@ -0,0 +1,448 @@
+Accelerator
+B3dCamera
+B3dTransformationSet
+B3dViewport
+BitmapMedianFilter
+BitmapMonochromeMatrixFilter
+BitmapPalette
+BitmapPopArtFilter
+BitmapSobelGreyFilter
+CalendarField
+CodeCompleteDataCache
+ConvertChar
+CurrencyBox
+CurrencyFormatter
+CursorWrapper
+DateBox
+DateField
+DdeGetPutItem
+DdeHotLink
+DdeItem
+DdeLink
+DdeService
+DdeTopic
+DockingAreaWindow
+DockingManager
+DoubleCurrencyField
+DoubleNumericField
+E3dCompoundObject
+E3dDefaultAttributes
+E3dExtrudeObj
+E3dPolygonObj
+EditAbstractDialogFactory
+EditUndo
+EditUndoManager
+EditViewCallbacks
+EnhancedCustomShape
+EnhancedCustomShape::FunctionParser
+FileChangedChecker
+FilterMatch
+FixedBitmap
+FixedHyperlink
+FmDesignModeChangedHint
+FmFormObj
+FmFormPageImpl
+FmXFormShell
+FontSelectPattern
+FontSizeNames
+FontSubsetInfo
+FormattedField::StaticFormatter
+FormatterBase
+FreetypeManager::IFSD_Equal
+GroupBox
+HelpLinker
+Hunspell
+Hunzip
+INetMIMEMessage
+INetMIMEMessageStream
+ImageControl
+ImplJobSetup
+IndexerPreProcessor
+IntroWindow
+ListenerMultiplexerBase
+LongCurrencyBox
+LongCurrencyField
+LongCurrencyFormatter
+MenuToggleButton
+MetaAction
+MetaArcAction
+MetaBmpAction
+MetaBmpExScalePartAction
+MetaBmpScaleAction
+MetaBmpScalePartAction
+MetaChordAction
+MetaClipRegionAction
+MetaEllipseAction
+MetaFontAction
+MetaGradientExAction
+MetaISectRectClipRegionAction
+MetaISectRegionClipRegionAction
+MetaLayoutModeAction
+MetaMapModeAction
+MetaMoveClipRegionAction
+MetaOverlineColorAction
+MetaPieAction
+MetaPixelAction
+MetaPolyLineAction
+MetaPolyPolygonAction
+MetaPolygonAction
+MetaPopAction
+MetaPushAction
+MetaRasterOpAction
+MetaRefPointAction
+MetaRoundRectAction
+MetaTextAlignAction
+MetaTextArrayAction
+MetaTextColorAction
+MetaTextFillColorAction
+MetaTextLanguageAction
+MetaTextLineColorAction
+MetaWallpaperAction
+MetafileAccessor
+ModuleSizeExceeded
+MoreButton
+MultiListBox
+MyThes
+NativeNumberWrapper
+NfCurrencyEntry
+NotebookbarTabControlBase
+NotifyEvent
+NumericBox
+NumericField
+OFlowChainedText
+OpenFileDropTargetListener
+OpenGLFramebuffer
+OpenGLZone
+PackedTextureAtlasManager
+PatternBox
+PatternField
+PatternFormatter
+PhysicalFontFamily
+PlaceEditDialog
+Point
+PrinterOptions
+ProgressBar
+QueueInfo
+RenderList
+SalData
+SalInfoPrinter
+SalPrinter
+SalSystem
+SbClassModuleObject
+SbMethod
+SbxInfo
+SbxObject
+SdrEmbedObjectLink
+SdrGrafBlueItem
+SdrGrafContrastItem
+SdrGrafCropItem
+SdrGrafGamma100Item
+SdrGrafGreenItem
+SdrGrafLuminanceItem
+SdrGrafModeItem
+SdrGrafRedItem
+SdrGrafTransparenceItem
+SdrMeasureField
+SdrMeasureObj
+SdrSignedPercentItem
+SdrTextFixedCellHeightItem
+SdrUndoPageMasterPage
+SelectionListenerMultiplexer
+SfxAllEnumItem
+SfxDocumentInfoItem
+SfxItemSetHint
+SfxMetricItem
+SfxNavigator
+SfxObjectItem
+SfxStatusListener
+SfxStyleSheetModifiedHint
+SfxTemplatePanelControl
+SfxViewFrameItem
+SgaObject
+SkiaPackedSurfaceAtlasManager
+SkiaZone
+SpinButton
+SpinListenerMultiplexer
+Storage
+SvParser<HtmlTokenId>::TokenStackType
+SvParser<int>::TokenStackType
+SvtBasePrintOptions
+SvtPrintFileOptions
+SvtPrinterOptions
+Svx3DCloseBackItem
+Svx3DCloseFrontItem
+Svx3DNormalsKindItem
+Svx3DPerspectiveItem
+Svx3DShadeModeItem
+Svx3DTextureKindItem
+Svx3DTextureModeItem
+Svx3DTextureProjectionXItem
+Svx3DTextureProjectionYItem
+SvxCurrencyToolBoxControl
+SvxEditSourceAdapter
+SvxGraphicObject
+SvxMetricField
+SvxPasswordDialog
+SvxPropertySetInfoPool
+SvxTPage
+SvxTextRotateItem
+SyntaxHighlighter::Tokenizer
+SystemWindow::ImplData
+TETextDataObject
+TabDialog
+TabPaneValue
+TextListenerMultiplexer
+Throbber
+TimeBox
+TimeFormatter
+TreeEditListenerMultiplexer
+TreeExpansionListenerMultiplexer
+TreeSelectionListenerMultiplexer
+UFlowChainedText
+UnoEditControl
+UnoWrapperBase
+VCLXDateField
+VCLXEdit
+VCLXMenuBar
+VCLXSpinField
+ValueSet
+VclAlignment
+VclBin
+VclBuilder::MenuAndId
+VclBuilder::ParserState
+VclBuilder::sortIntoBestTabTraversalOrder
+VclDrawingArea
+VclGrid
+VclWindowEvent
+VersionCompat
+XMLDashStyleExport
+XMLDashStyleImport
+XMLGradientStyleExport
+XMLGradientStyleImport
+XMLHatchStyleExport
+XMLHatchStyleImport
+XMLImageStyle
+XMLMarkerStyleExport
+XMLMarkerStyleImport
+XMLShapeStyleContext
+accessibility::AccessibleEditableTextPara
+accessibility::AccessibleParaManager
+avmedia::MediaControlBase
+avmedia::MediaFloater
+basegfx::B2DTrapezoid
+basegfx::B3DPoint
+basegfx::B3DTuple
+basegfx::BColorModifier
+basegfx::BColorModifierStack
+basegfx::BColorModifier_RGBLuminanceContrast
+basegfx::BColorModifier_black_and_white
+basegfx::BColorModifier_gamma
+basegfx::BColorModifier_gray
+basegfx::BColorModifier_invert
+basegfx::BColorModifier_replace
+basegfx::MinimalSystemDependentDataManager
+basegfx::ODFGradientInfo
+basegfx::RasterConverter3D
+basegfx::SystemDependentDataHolder
+basegfx::SystemDependentDataManager
+basegfx::triangulator
+canvas
+char& std::vector<char, std::allocator<char> >
+comphelper::IndexAccessIterator
+comphelper::OAccessibleSelectionHelper
+comphelper::OEventListenerHelper
+comphelper::OPropertySetAggregationHelper
+comphelper::OPropertyStateHelper
+comphelper::OSequenceOutputStream
+comphelper::OStatefulPropertySet
+comphelper::OStreamSection
+comphelper::OWeakEventListenerAdapter
+comphelper::OWrappedAccessibleChildrenManager
+comphelper::PropertyBag
+comphelper::StillReadWriteInteraction
+comphelper::service_decl::ServiceDecl::Factory
+connectivity::sdbcx::IObjectCollection
+connectivity::sdbcx::OGroup
+connectivity::sdbcx::OKey
+dbtools::param::ParameterWrapper
+desktop::CallbackFlushHandler::CallbackData
+dp_misc::AbortChannel
+drawinglayer::animation::AnimationEntry
+drawinglayer::animation::AnimationEntryFixed
+drawinglayer::animation::AnimationEntryLinear
+drawinglayer::animation::AnimationEntryList
+drawinglayer::animation::AnimationEntryLoop
+drawinglayer::attribute::FillGraphicAttribute
+drawinglayer::attribute::FillHatchAttribute
+drawinglayer::attribute::LineStartEndAttribute
+drawinglayer::attribute::MaterialAttribute3D
+drawinglayer::attribute::Sdr3DLightAttribute
+drawinglayer::attribute::Sdr3DObjectAttribute
+drawinglayer::attribute::SdrFillGraphicAttribute
+drawinglayer::attribute::SdrGlowAttribute
+drawinglayer::attribute::SdrLightingAttribute
+drawinglayer::attribute::SdrLineAttribute
+drawinglayer::attribute::SdrLineFillShadowAttribute3D
+drawinglayer::attribute::SdrLineStartEndAttribute
+drawinglayer::attribute::SdrSceneAttribute
+drawinglayer::attribute::SdrShadowAttribute
+drawinglayer::primitive2d::AnimatedBlinkPrimitive2D
+drawinglayer::primitive2d::AnimatedInterpolatePrimitive2D
+drawinglayer::primitive2d::AnimatedSwitchPrimitive2D
+drawinglayer::primitive2d::BackgroundColorPrimitive2D
+drawinglayer::primitive2d::ControlPrimitive2D
+drawinglayer::primitive2d::DiscreteShadowPrimitive2D
+drawinglayer::primitive2d::Embedded3DPrimitive2D
+drawinglayer::primitive2d::FillGraphicPrimitive2D
+drawinglayer::primitive2d::GlowPrimitive2D
+drawinglayer::primitive2d::GridPrimitive2D
+drawinglayer::primitive2d::GroupPrimitive2D
+drawinglayer::primitive2d::HelplinePrimitive2D
+drawinglayer::primitive2d::InvertPrimitive2D
+drawinglayer::primitive2d::MarkerArrayPrimitive2D
+drawinglayer::primitive2d::MediaPrimitive2D
+drawinglayer::primitive2d::MetafilePrimitive2D
+drawinglayer::primitive2d::ObjectAndViewTransformationDependentPrimitive2D
+drawinglayer::primitive2d::PagePreviewPrimitive2D
+drawinglayer::primitive2d::PolyPolygonGradientPrimitive2D
+drawinglayer::primitive2d::PolyPolygonGraphicPrimitive2D
+drawinglayer::primitive2d::PolyPolygonHatchPrimitive2D
+drawinglayer::primitive2d::PolyPolygonSelectionPrimitive2D
+drawinglayer::primitive2d::PolygonMarkerPrimitive2D
+drawinglayer::primitive2d::PolygonStrokeArrowPrimitive2D
+drawinglayer::primitive2d::ScenePrimitive2D
+drawinglayer::primitive2d::SdrFrameBorderData::SdrConnectStyleData
+drawinglayer::primitive2d::ShadowPrimitive2D
+drawinglayer::primitive2d::TextHierarchyBlockPrimitive2D
+drawinglayer::primitive2d::TextHierarchyBulletPrimitive2D
+drawinglayer::primitive2d::TextHierarchyEditPrimitive2D
+drawinglayer::primitive2d::TextHierarchyFieldPrimitive2D
+drawinglayer::primitive2d::TextHierarchyLinePrimitive2D
+drawinglayer::primitive2d::TextHierarchyParagraphPrimitive2D
+drawinglayer::primitive2d::ViewTransformationDependentPrimitive2D
+drawinglayer::primitive2d::ViewportDependentPrimitive2D
+drawinglayer::primitive2d::WrongSpellPrimitive2D
+drawinglayer::primitive3d
+drawinglayer::primitive3d::BasePrimitive3D
+drawinglayer::primitive3d::BufferedDecompositionPrimitive3D
+drawinglayer::primitive3d::GroupPrimitive3D
+drawinglayer::primitive3d::ModifiedColorPrimitive3D
+drawinglayer::primitive3d::PolyPolygonMaterialPrimitive3D
+drawinglayer::primitive3d::PolygonHairlinePrimitive3D
+drawinglayer::primitive3d::Primitive3DContainer
+drawinglayer::primitive3d::SdrCubePrimitive3D
+drawinglayer::primitive3d::SdrExtrudePrimitive3D
+drawinglayer::primitive3d::SdrLathePrimitive3D
+drawinglayer::primitive3d::SdrPolyPolygonPrimitive3D
+drawinglayer::primitive3d::SdrPrimitive3D
+drawinglayer::primitive3d::SdrSpherePrimitive3D
+drawinglayer::primitive3d::TransformPrimitive3D
+drawinglayer::processor2d::HitTestProcessor2D
+drawinglayer::processor3d::BaseProcessor3D
+drawinglayer::processor3d::CutFindProcessor
+emfio::WinMtfFontStyle
+formula::FormulaTokenIterator::Item
+framework
+framework::AddonMenuManager
+framework::AddonsOptions
+framework::ConfigAccess
+framework::ConstItemContainer
+framework::Converter
+framework::DispatchHelper
+framework::FrameListAnalyzer
+framework::HandlerCache
+framework::InteractionRequest
+framework::MenuAttributes
+framework::MenuConfiguration
+framework::RequestFilterSelect
+framework::RootItemContainer
+framework::SaxNamespaceFilter
+framework::StatusBarConfiguration
+framework::ToolBoxConfiguration
+framework::TransactionManager
+framework::UIConfigurationImporterOOo1x
+i18nutil::casefolding
+i18nutil::oneToOneMapping
+i18nutil::widthfolding
+legacy::CntInt32
+legacy::SfxBool
+legacy::SvxAdjust
+legacy::SvxBox
+legacy::SvxBrush
+legacy::SvxColor
+legacy::SvxCrossedOut
+legacy::SvxFont
+legacy::SvxFontHeight
+legacy::SvxHorJustify
+legacy::SvxLine
+legacy::SvxPosture
+legacy::SvxTextLine
+legacy::SvxVerJustify
+legacy::SvxWeight
+linguistic::HyphenatedWord
+linguistic::PossibleHyphens
+linguistic::PropertyChgHelper
+linguistic::PropertyHelper_Hyphenation
+linguistic::PropertyHelper_Spell
+linguistic::PropertyHelper_Spelling
+linguistic::PropertyHelper_Thesaurus
+linguistic::SpellAlternatives
+psp::PrintFontManager::PrintFont
+sdr::SelectionController
+sdr::ViewSelection
+sdr::animation::primitiveAnimator
+sdr::contact::ObjectContactPainter
+sdr::properties::BaseProperties
+sdr::table::Cell
+sfx2::sidebar::Panel
+sfx2::sidebar::SidebarToolBox
+sfx2::sidebar::TabBar
+sfx2::sidebar::TabBar::Item
+svt
+svt::AddressBookSourceDialog
+svt::GenericToolboxController
+svt::GraphicAccess
+svt::IEditImplementation
+svt::MultiLineEditImplementation
+svt::MultiLineTextCell
+svt::OStringTransferable
+svt::PopupMenuControllerBase
+svt::SpinCellController
+svt::TemplateFolderCache
+svtools::AsynchronLink
+svtools::ToolbarPopup
+svx::DialControl::DialControl_Impl
+svx::IPropertyValueProvider
+svx::sidebar::GalleryControl
+svxform
+svxform::DataNavigatorManager
+svxform::NavigatorFrameManager
+svxform::OLocalExchange
+svxform::OLocalExchangeHelper
+svxform::OSQLParserClient
+toolkitform
+tools::WeakBase
+ucbhelper::ActiveDataSink
+ucbhelper::InteractionApprove
+ucbhelper::InteractionDisapprove
+ucbhelper::InteractionSupplyAuthentication
+ucbhelper::InterceptedInteraction
+ucbhelper::SimpleNameClashResolveRequest
+utl::Bootstrap::Impl
+utl::DefaultFontConfiguration
+utl::DesktopTerminationObserver
+utl::FontSubstConfiguration
+utl::OConfigurationValueContainer
+utl::ProgressHandlerWrap
+utl::ZipPackageHelper
+utl::detail::Options
+vcl::AccessibleFactoryAccess
+vcl::EventPoster
+vcl::ExtOutDevData
+vcl::ILibreOfficeKitNotifier
+vcl::ORoadmap
+vcl::OldStylePrintAdaptor
+vcl::PDFWriter::AnyWidget
+vcl::test::OutputDeviceTestGradient
+void OpenGLTexture
+wchar_t& std::vector<wchar_t, std::allocator<wchar_t> >
diff --git a/bin/find-mergedlib-can-be-private.py b/bin/find-mergedlib-can-be-private.py
new file mode 100755
index 000000000000..572cd1c8e005
--- /dev/null
+++ b/bin/find-mergedlib-can-be-private.py
@@ -0,0 +1,152 @@
+#!/usr/bin/python2
+#
+# Generate a custom linker script/map file for the --enabled-mergedlibs merged library
+# which reduces the startup time and enables further optimisations with --enable-lto because 60% or more
+# of the symbols become internal only.
+#
+
+import subprocess
+import sys
+import re
+
+exported_symbols = set()
+imported_symbols = set()
+
+
+# Copied from solenv/gbuild/extensions/pre_MergedLibsList.mk
+# TODO there has to be a way to run gmake and get it to dump this list for me
+merged_libs = { \
+    "avmedia" \
+    ,"basctl" \
+    ,"basprov" \
+    ,"basegfx" \
+    ,"canvasfactory" \
+    ,"canvastools" \
+    ,"comphelper" \
+    ,"configmgr" \
+    ,"cppcanvas" \
+    ,"crashreport)" \
+    ,"dbtools" \
+    ,"deployment" \
+    ,"deploymentmisc" \
+    ,"desktopbe1)" \
+    ,"desktop_detector)" \
+    ,"drawinglayer" \
+    ,"editeng" \
+    ,"expwrap" \
+    ,"filterconfig" \
+    ,"fsstorage" \
+    ,"fwe" \
+    ,"fwi" \
+    ,"fwk" \
+    ,"helplinker)" \
+    ,"i18npool" \
+    ,"i18nutil" \
+    ,"lng" \
+    ,"localebe1" \
+    ,"mcnttype" \
+    ,"msfilter" \
+    ,"mtfrenderer" \
+    ,"opencl" \
+    ,"package2" \
+    ,"sax" \
+    ,"sb" \
+    ,"simplecanvas" \
+    ,"sfx" \
+    ,"sofficeapp" \
+    ,"sot" \
+    ,"spl" \
+    ,"stringresource" \
+    ,"svl" \
+    ,"svt" \
+    ,"svx" \
+    ,"svxcore" \
+    ,"tk" \
+    ,"tl" \
+    ,"ucb1" \
+    ,"ucbhelper" \
+    ,"ucpexpand1" \
+    ,"ucpfile1" \
+    ,"unoxml" \
+    ,"utl" \
+    ,"uui" \
+    ,"vcl" \
+    ,"xmlscript" \
+    ,"xo" \
+    ,"xstor" }
+
+classes_with_exported_symbols = set()
+classes_with_imported_symbols = set()
+
+# look for symbols exported by libmerged
+subprocess_nm = subprocess.Popen("nm -D instdir/program/libmergedlo.so", stdout=subprocess.PIPE, shell=True)
+with subprocess_nm.stdout as txt:
+    # We are looking for lines something like:
+    # 0000000000036ed0 T flash_component_getFactory
+    line_regex = re.compile(r'^[0-9a-fA-F]+ T ')
+    for line in txt:
+        line = line.strip()
+        if line_regex.match(line):
+            exported_symbols.add(line.split(" ")[2])
+subprocess_nm.terminate()
+
+# look for symbols imported from libmerged
+subprocess_find = subprocess.Popen("(find instdir/program/ -type f; ls ./workdir/LinkTarget/CppunitTest/*.so) | xargs grep -l mergedlo",
+        stdout=subprocess.PIPE, shell=True)
+with subprocess_find.stdout as txt:
+    for line in txt:
+        sharedlib = line.strip()
+        s = sharedlib[sharedlib.find("/lib") + 4 : len(sharedlib) - 3]
+        if s in merged_libs: continue
+        # look for imported symbols
+        subprocess_objdump = subprocess.Popen("objdump -T " + sharedlib, stdout=subprocess.PIPE, shell=True)
+        with subprocess_objdump.stdout as txt2:
+            # ignore some header bumpf
+            txt2.readline()
+            txt2.readline()
+            txt2.readline()
+            txt2.readline()
+            # We are looking for lines something like (noting that one of them uses spaces, and the other tabs)
+            # 0000000000000000      DF *UND*  0000000000000000     _ZN16FilterConfigItem10WriteInt32ERKN3rtl8OUStringEi
+            for line2 in txt2:
+                line2 = line2.strip()
+                if line2.find("*UND*") == -1: continue
+                tokens = line2.split(" ")
+                sym = tokens[len(tokens)-1].strip()
+                imported_symbols.add(sym)
+        subprocess_objdump.terminate()
+subprocess_find.terminate()
+
+intersec_symbols = exported_symbols.intersection(imported_symbols)
+print("no symbols exported from libmerged   = " + str(len(exported_symbols)))
+print("no symbols that can be made internal = " + str(len(intersec_symbols)))
+
+# Now look for classes where none of the class symbols are imported,
+# i.e. we can mark the whole class as hidden
+
+def extract_class(sym, add_to_set):
+    filtered_sym = subprocess.check_output(["c++filt", sym]).strip()
+    if filtered_sym.startswith("vtable for "):
+        classname = filtered_sym[11:]
+        add_to_set.add(classname)
+        return
+    if filtered_sym.startswith("non-virtual thunk to "):
+        filtered_sym = filtered_sym[21:]
+    elif filtered_sym.startswith("virtual thunk to "):
+        filtered_sym = filtered_sym[17:]
+    i = filtered_sym.find("(")
+    if i != -1:
+        i = filtered_sym.rfind("::", 0, i)
+        if i != -1:
+            classname = filtered_sym[:i]
+            add_to_set.add(classname)
+
+for sym in exported_symbols:
+    extract_class(sym, classes_with_exported_symbols)
+for sym in imported_symbols:
+    extract_class(sym, classes_with_imported_symbols)
+
+with open("bin/find-mergedlib-can-be-private.classes.results", "wt") as f:
+    for sym in sorted(classes_with_exported_symbols - classes_with_imported_symbols):
+        if sym.startswith("std::") or sym.startswith("void std::"): continue
+        f.write(sym + "\n")