From 20425d92dfb39377e6b8eb111971d5ac3042421a Mon Sep 17 00:00:00 2001 From: Lang Hames Date: Thu, 20 Mar 2014 21:06:46 +0000 Subject: Add an option to MCJIT to have it forward all sections to the RTDyldMemoryManager, regardless of whether it thinks they're "required for execution". Currently, RuntimeDyld only passes sections that are "required for execution" to the RTDyldMemoryManager, and takes "required for execution" to mean exactly "contains symbols or relocations". There are two problems with this: (1) It can drop sections with anonymous data that is referenced by code. (2) It leaves the JIT client no way to inspect interesting sections that aren't actually required to run the program (e.g dwarf sections). A test case is still in the works. Future work: We may want to replace this with a generic section filtering mechanism, but that will require more consideration. For now, this flag at least allows clients to volunteer to do the filtering themselves. Fixes . git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@204398 91177308-0d34-0410-b5e6-96231b3b80d8 --- lib/ExecutionEngine/RuntimeDyld/RuntimeDyld.cpp | 46 +++++++++++++++-------- lib/ExecutionEngine/RuntimeDyld/RuntimeDyldImpl.h | 11 +++++- 2 files changed, 40 insertions(+), 17 deletions(-) (limited to 'lib/ExecutionEngine/RuntimeDyld') diff --git a/lib/ExecutionEngine/RuntimeDyld/RuntimeDyld.cpp b/lib/ExecutionEngine/RuntimeDyld/RuntimeDyld.cpp index 5d6a2c0f12..310b206a06 100644 --- a/lib/ExecutionEngine/RuntimeDyld/RuntimeDyld.cpp +++ b/lib/ExecutionEngine/RuntimeDyld/RuntimeDyld.cpp @@ -161,25 +161,22 @@ ObjectImage* RuntimeDyldImpl::loadObject(ObjectImage *InputObject) { DEBUG(dbgs() << "Parse relocations:\n"); for (section_iterator SI = Obj->begin_sections(), SE = Obj->end_sections(); SI != SE; ++SI) { - bool IsFirstRelocation = true; unsigned SectionID = 0; StubMap Stubs; section_iterator RelocatedSection = SI->getRelocatedSection(); - for (const RelocationRef &Reloc : SI->relocations()) { - // If it's the first relocation in this section, find its SectionID - if (IsFirstRelocation) { - bool IsCode = false; - Check(RelocatedSection->isText(IsCode)); - SectionID = - findOrEmitSection(*Obj, *RelocatedSection, IsCode, LocalSections); - DEBUG(dbgs() << "\tSectionID: " << SectionID << "\n"); - IsFirstRelocation = false; - } + if ((SI->relocation_begin() != SI->relocation_end()) || + ProcessAllSections) { + bool IsCode = false; + Check(RelocatedSection->isText(IsCode)); + SectionID = + findOrEmitSection(*Obj, *RelocatedSection, IsCode, LocalSections); + DEBUG(dbgs() << "\tSectionID: " << SectionID << "\n"); + } + for (const RelocationRef &Reloc : SI->relocations()) processRelocationRef(SectionID, Reloc, *Obj, LocalSections, LocalSymbols, Stubs); - } } // Give the subclasses a chance to tie-up any loose ends. @@ -665,23 +662,40 @@ RuntimeDyld::RuntimeDyld(RTDyldMemoryManager *mm) { // permissions are applied. Dyld = 0; MM = mm; + ProcessAllSections = false; } RuntimeDyld::~RuntimeDyld() { delete Dyld; } +static std::unique_ptr createRuntimeDyldELF( + RTDyldMemoryManager *MM, + bool ProcessAllSections) { + std::unique_ptr Dyld(new RuntimeDyldELF(MM)); + Dyld->setProcessAllSections(ProcessAllSections); + return Dyld; +} + +static std::unique_ptr createRuntimeDyldMachO( + RTDyldMemoryManager *MM, + bool ProcessAllSections) { + std::unique_ptr Dyld(new RuntimeDyldMachO(MM)); + Dyld->setProcessAllSections(ProcessAllSections); + return Dyld; +} + ObjectImage *RuntimeDyld::loadObject(ObjectFile *InputObject) { std::unique_ptr InputImage; if (InputObject->isELF()) { InputImage.reset(RuntimeDyldELF::createObjectImageFromFile(InputObject)); if (!Dyld) - Dyld = new RuntimeDyldELF(MM); + Dyld = createRuntimeDyldELF(MM, ProcessAllSections).release(); } else if (InputObject->isMachO()) { InputImage.reset(RuntimeDyldMachO::createObjectImageFromFile(InputObject)); if (!Dyld) - Dyld = new RuntimeDyldMachO(MM); + Dyld = createRuntimeDyldMachO(MM, ProcessAllSections).release(); } else report_fatal_error("Incompatible object format!"); @@ -704,7 +718,7 @@ ObjectImage *RuntimeDyld::loadObject(ObjectBuffer *InputBuffer) { case sys::fs::file_magic::elf_core: InputImage.reset(RuntimeDyldELF::createObjectImage(InputBuffer)); if (!Dyld) - Dyld = new RuntimeDyldELF(MM); + Dyld = createRuntimeDyldELF(MM, ProcessAllSections).release(); break; case sys::fs::file_magic::macho_object: case sys::fs::file_magic::macho_executable: @@ -718,7 +732,7 @@ ObjectImage *RuntimeDyld::loadObject(ObjectBuffer *InputBuffer) { case sys::fs::file_magic::macho_dsym_companion: InputImage.reset(RuntimeDyldMachO::createObjectImage(InputBuffer)); if (!Dyld) - Dyld = new RuntimeDyldMachO(MM); + Dyld = createRuntimeDyldMachO(MM, ProcessAllSections).release(); break; case sys::fs::file_magic::unknown: case sys::fs::file_magic::bitcode: diff --git a/lib/ExecutionEngine/RuntimeDyld/RuntimeDyldImpl.h b/lib/ExecutionEngine/RuntimeDyld/RuntimeDyldImpl.h index 8fd55920f2..0b7de17a6e 100644 --- a/lib/ExecutionEngine/RuntimeDyld/RuntimeDyldImpl.h +++ b/lib/ExecutionEngine/RuntimeDyld/RuntimeDyldImpl.h @@ -187,6 +187,10 @@ protected: Triple::ArchType Arch; bool IsTargetLittleEndian; + // True if all sections should be passed to the memory manager, false if only + // sections containing relocations should be. Defaults to 'false'. + bool ProcessAllSections; + // This mutex prevents simultaneously loading objects from two different // threads. This keeps us from having to protect individual data structures // and guarantees that section allocation requests to the memory manager @@ -320,10 +324,15 @@ protected: unsigned computeSectionStubBufSize(ObjectImage &Obj, const SectionRef &Section); public: - RuntimeDyldImpl(RTDyldMemoryManager *mm) : MemMgr(mm), HasError(false) {} + RuntimeDyldImpl(RTDyldMemoryManager *mm) + : MemMgr(mm), ProcessAllSections(false), HasError(false) {} virtual ~RuntimeDyldImpl(); + void setProcessAllSections(bool ProcessAllSections) { + this->ProcessAllSections = ProcessAllSections; + } + ObjectImage* loadObject(ObjectImage* InputObject); void *getSymbolAddress(StringRef Name) { -- cgit v1.2.3