Author: labath Date: Fri May 10 00:54:37 2019 New Revision: 360409 URL: http://llvm.org/viewvc/llvm-project?rev=360409&view=rev Log: FuncUnwinders: Add a new "SymbolFile" unwind plan
Summary: some unwind formats are specific to a single symbol file and so it does not make sense for their parsing code live in the general Symbol library (as is the case with eh_frame for instance). This is the case for the unwind information in breakpad files, but the same will probably be true for PDB unwind info (once we are able to parse that). This patch adds the ability to fetch an unwind plan provided by a symbol file plugin, as discussed in the RFC at <http://lists.llvm.org/pipermail/lldb-dev/2019-February/014703.html>. I've kept the set of changes to a minimum, as there is no way to test them until we have a symbol file which implements this API -- that is comming in a follow-up patch, which will also implicitly test this change. The interesting part here is the introduction of the "RegisterInfoResolver" interface. The reason for this is that breakpad needs to be able to resolve register names (which are present as strings in the file) into register enums so that it can construct the unwind plan. This is normally done via the RegisterContext class, handing this over to the SymbolFile plugin would mean that it has full access to the debugged process, which is not something we want it to have. So instead, I create a facade, which only provides the ability to query register names, and hide the RegisterContext behind the facade. Also note that this only adds the ability to dump the unwind plan created by the symbol file plugin -- the plan is not used for unwinding yet -- this will be added in a third patch, which will add additional tests which makes sure the unwinding works as a whole. Reviewers: jasonmolenda, clayborg Subscribers: markmentovai, amccarth, lldb-commits Differential Revision: https://reviews.llvm.org/D61732 Modified: lldb/trunk/include/lldb/Symbol/FuncUnwinders.h lldb/trunk/include/lldb/Symbol/SymbolFile.h lldb/trunk/include/lldb/Symbol/UnwindTable.h lldb/trunk/source/Commands/CommandObjectTarget.cpp lldb/trunk/source/Symbol/FuncUnwinders.cpp lldb/trunk/source/Symbol/SymbolFile.cpp lldb/trunk/source/Symbol/UnwindTable.cpp Modified: lldb/trunk/include/lldb/Symbol/FuncUnwinders.h URL: http://llvm.org/viewvc/llvm-project/lldb/trunk/include/lldb/Symbol/FuncUnwinders.h?rev=360409&r1=360408&r2=360409&view=diff ============================================================================== --- lldb/trunk/include/lldb/Symbol/FuncUnwinders.h (original) +++ lldb/trunk/include/lldb/Symbol/FuncUnwinders.h Fri May 10 00:54:37 2019 @@ -90,6 +90,8 @@ public: lldb::UnwindPlanSP GetArmUnwindUnwindPlan(Target &target); + lldb::UnwindPlanSP GetSymbolFileUnwindPlan(Thread &thread); + lldb::UnwindPlanSP GetArchDefaultUnwindPlan(Thread &thread); lldb::UnwindPlanSP GetArchDefaultAtFuncEntryUnwindPlan(Thread &thread); @@ -120,6 +122,7 @@ private: std::vector<lldb::UnwindPlanSP> m_unwind_plan_compact_unwind; lldb::UnwindPlanSP m_unwind_plan_arm_unwind_sp; + lldb::UnwindPlanSP m_unwind_plan_symbol_file_sp; lldb::UnwindPlanSP m_unwind_plan_fast_sp; lldb::UnwindPlanSP m_unwind_plan_arch_default_sp; lldb::UnwindPlanSP m_unwind_plan_arch_default_at_func_entry_sp; @@ -131,8 +134,8 @@ private: m_tried_unwind_plan_eh_frame_augmented : 1, m_tried_unwind_plan_debug_frame_augmented : 1, m_tried_unwind_plan_compact_unwind : 1, - m_tried_unwind_plan_arm_unwind : 1, m_tried_unwind_fast : 1, - m_tried_unwind_arch_default : 1, + m_tried_unwind_plan_arm_unwind : 1, m_tried_unwind_plan_symbol_file : 1, + m_tried_unwind_fast : 1, m_tried_unwind_arch_default : 1, m_tried_unwind_arch_default_at_func_entry : 1; Address m_first_non_prologue_insn; Modified: lldb/trunk/include/lldb/Symbol/SymbolFile.h URL: http://llvm.org/viewvc/llvm-project/lldb/trunk/include/lldb/Symbol/SymbolFile.h?rev=360409&r1=360408&r2=360409&view=diff ============================================================================== --- lldb/trunk/include/lldb/Symbol/SymbolFile.h (original) +++ lldb/trunk/include/lldb/Symbol/SymbolFile.h Fri May 10 00:54:37 2019 @@ -223,6 +223,18 @@ public: /// for this module have been changed. virtual void SectionFileAddressesChanged() {} + struct RegisterInfoResolver { + virtual ~RegisterInfoResolver(); // anchor + + virtual const RegisterInfo *ResolveName(llvm::StringRef name) const = 0; + virtual const RegisterInfo *ResolveNumber(lldb::RegisterKind kind, + uint32_t number) const = 0; + }; + virtual lldb::UnwindPlanSP + GetUnwindPlan(const Address &address, const RegisterInfoResolver &resolver) { + return nullptr; + } + virtual void Dump(Stream &s) {} protected: Modified: lldb/trunk/include/lldb/Symbol/UnwindTable.h URL: http://llvm.org/viewvc/llvm-project/lldb/trunk/include/lldb/Symbol/UnwindTable.h?rev=360409&r1=360408&r2=360409&view=diff ============================================================================== --- lldb/trunk/include/lldb/Symbol/UnwindTable.h (original) +++ lldb/trunk/include/lldb/Symbol/UnwindTable.h Fri May 10 00:54:37 2019 @@ -33,6 +33,7 @@ public: lldb_private::CompactUnwindInfo *GetCompactUnwindInfo(); ArmUnwindInfo *GetArmUnwindInfo(); + SymbolFile *GetSymbolFile(); lldb::FuncUnwindersSP GetFuncUnwindersContainingAddress(const Address &addr, SymbolContext &sc); Modified: lldb/trunk/source/Commands/CommandObjectTarget.cpp URL: http://llvm.org/viewvc/llvm-project/lldb/trunk/source/Commands/CommandObjectTarget.cpp?rev=360409&r1=360408&r2=360409&view=diff ============================================================================== --- lldb/trunk/source/Commands/CommandObjectTarget.cpp (original) +++ lldb/trunk/source/Commands/CommandObjectTarget.cpp Fri May 10 00:54:37 2019 @@ -3591,6 +3591,14 @@ protected: result.GetOutputStream().Printf("\n"); } + if (UnwindPlanSP symfile_plan_sp = + func_unwinders_sp->GetSymbolFileUnwindPlan(*thread)) { + result.GetOutputStream().Printf("Symbol file UnwindPlan:\n"); + symfile_plan_sp->Dump(result.GetOutputStream(), thread.get(), + LLDB_INVALID_ADDRESS); + result.GetOutputStream().Printf("\n"); + } + UnwindPlanSP compact_unwind_sp = func_unwinders_sp->GetCompactUnwindUnwindPlan(*target); if (compact_unwind_sp) { Modified: lldb/trunk/source/Symbol/FuncUnwinders.cpp URL: http://llvm.org/viewvc/llvm-project/lldb/trunk/source/Symbol/FuncUnwinders.cpp?rev=360409&r1=360408&r2=360409&view=diff ============================================================================== --- lldb/trunk/source/Symbol/FuncUnwinders.cpp (original) +++ lldb/trunk/source/Symbol/FuncUnwinders.cpp Fri May 10 00:54:37 2019 @@ -13,11 +13,13 @@ #include "lldb/Symbol/CompactUnwindInfo.h" #include "lldb/Symbol/DWARFCallFrameInfo.h" #include "lldb/Symbol/ObjectFile.h" +#include "lldb/Symbol/SymbolFile.h" #include "lldb/Symbol/UnwindPlan.h" #include "lldb/Symbol/UnwindTable.h" #include "lldb/Target/ABI.h" #include "lldb/Target/ExecutionContext.h" #include "lldb/Target/Process.h" +#include "lldb/Target/RegisterContext.h" #include "lldb/Target/RegisterNumber.h" #include "lldb/Target/Target.h" #include "lldb/Target/Thread.h" @@ -42,7 +44,8 @@ FuncUnwinders::FuncUnwinders(UnwindTable m_tried_unwind_plan_eh_frame_augmented(false), m_tried_unwind_plan_debug_frame_augmented(false), m_tried_unwind_plan_compact_unwind(false), - m_tried_unwind_plan_arm_unwind(false), m_tried_unwind_fast(false), + m_tried_unwind_plan_arm_unwind(false), + m_tried_unwind_plan_symbol_file(false), m_tried_unwind_fast(false), m_tried_unwind_arch_default(false), m_tried_unwind_arch_default_at_func_entry(false), m_first_non_prologue_insn() {} @@ -147,6 +150,38 @@ UnwindPlanSP FuncUnwinders::GetArmUnwind return m_unwind_plan_arm_unwind_sp; } +namespace { +class RegisterContextToInfo: public SymbolFile::RegisterInfoResolver { +public: + RegisterContextToInfo(RegisterContext &ctx) : m_ctx(ctx) {} + + const RegisterInfo *ResolveName(llvm::StringRef name) const { + return m_ctx.GetRegisterInfoByName(name); + } + const RegisterInfo *ResolveNumber(lldb::RegisterKind kind, + uint32_t number) const { + return m_ctx.GetRegisterInfo(kind, number); + } + +private: + RegisterContext &m_ctx; +}; +} // namespace + +UnwindPlanSP FuncUnwinders::GetSymbolFileUnwindPlan(Thread &thread) { + std::lock_guard<std::recursive_mutex> guard(m_mutex); + if (m_unwind_plan_symbol_file_sp.get() || m_tried_unwind_plan_symbol_file) + return m_unwind_plan_symbol_file_sp; + + m_tried_unwind_plan_symbol_file = true; + if (SymbolFile *symfile = m_unwind_table.GetSymbolFile()) { + m_unwind_plan_symbol_file_sp = symfile->GetUnwindPlan( + m_range.GetBaseAddress(), + RegisterContextToInfo(*thread.GetRegisterContext())); + } + return m_unwind_plan_symbol_file_sp; +} + UnwindPlanSP FuncUnwinders::GetEHFrameAugmentedUnwindPlan(Target &target, Thread &thread) { std::lock_guard<std::recursive_mutex> guard(m_mutex); Modified: lldb/trunk/source/Symbol/SymbolFile.cpp URL: http://llvm.org/viewvc/llvm-project/lldb/trunk/source/Symbol/SymbolFile.cpp?rev=360409&r1=360408&r2=360409&view=diff ============================================================================== --- lldb/trunk/source/Symbol/SymbolFile.cpp (original) +++ lldb/trunk/source/Symbol/SymbolFile.cpp Fri May 10 00:54:37 2019 @@ -168,3 +168,5 @@ void SymbolFile::AssertModuleLock() { "Module is not locked"); #endif } + +SymbolFile::RegisterInfoResolver::~RegisterInfoResolver() = default; Modified: lldb/trunk/source/Symbol/UnwindTable.cpp URL: http://llvm.org/viewvc/llvm-project/lldb/trunk/source/Symbol/UnwindTable.cpp?rev=360409&r1=360408&r2=360409&view=diff ============================================================================== --- lldb/trunk/source/Symbol/UnwindTable.cpp (original) +++ lldb/trunk/source/Symbol/UnwindTable.cpp Fri May 10 00:54:37 2019 @@ -18,6 +18,7 @@ #include "lldb/Symbol/FuncUnwinders.h" #include "lldb/Symbol/ObjectFile.h" #include "lldb/Symbol/SymbolContext.h" +#include "lldb/Symbol/SymbolVendor.h" // There is one UnwindTable object per ObjectFile. It contains a list of Unwind // objects -- one per function, populated lazily -- for the ObjectFile. Each @@ -181,6 +182,12 @@ ArmUnwindInfo *UnwindTable::GetArmUnwind return m_arm_unwind_up.get(); } +SymbolFile *UnwindTable::GetSymbolFile() { + if (SymbolVendor *vendor = m_module.GetSymbolVendor()) + return vendor->GetSymbolFile(); + return nullptr; +} + ArchSpec UnwindTable::GetArchitecture() { return m_module.GetArchitecture(); } bool UnwindTable::GetAllowAssemblyEmulationUnwindPlans() { _______________________________________________ lldb-commits mailing list lldb-commits@lists.llvm.org https://lists.llvm.org/cgi-bin/mailman/listinfo/lldb-commits
