Coverage Report

Created: 2022-01-18 06:27

/Users/buildslave/jenkins/workspace/coverage/llvm-project/lldb/source/Plugins/ABI/X86/ABISysV_i386.h
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//===------------------- ABISysV_i386.h -------------------------*- C++ -*-===//
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//
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// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
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// See https://llvm.org/LICENSE.txt for license information.
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// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
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//
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//===----------------------------------------------------------------------===//
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#ifndef LLDB_SOURCE_PLUGINS_ABI_X86_ABISYSV_I386_H
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#define LLDB_SOURCE_PLUGINS_ABI_X86_ABISYSV_I386_H
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#include "Plugins/ABI/X86/ABIX86_i386.h"
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#include "lldb/lldb-private.h"
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class ABISysV_i386 : public ABIX86_i386 {
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public:
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  ~ABISysV_i386() override = default;
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  size_t GetRedZoneSize() const override {
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    return 0; // There is no red zone for i386 Architecture
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  }
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  bool PrepareTrivialCall(lldb_private::Thread &thread, lldb::addr_t sp,
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                          lldb::addr_t functionAddress,
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                          lldb::addr_t returnAddress,
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                          llvm::ArrayRef<lldb::addr_t> args) const override;
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  bool GetArgumentValues(lldb_private::Thread &thread,
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                         lldb_private::ValueList &values) const override;
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  lldb_private::Status
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  SetReturnValueObject(lldb::StackFrameSP &frame_sp,
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                       lldb::ValueObjectSP &new_value) override;
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  lldb::ValueObjectSP
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  GetReturnValueObjectImpl(lldb_private::Thread &thread,
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                           lldb_private::CompilerType &type) const override;
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  bool
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  CreateFunctionEntryUnwindPlan(lldb_private::UnwindPlan &unwind_plan) override;
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  bool CreateDefaultUnwindPlan(lldb_private::UnwindPlan &unwind_plan) override;
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  bool RegisterIsVolatile(const lldb_private::RegisterInfo *reg_info) override {
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    return !RegisterIsCalleeSaved(reg_info);
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  }
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  // The SysV i386 ABI requires that stack frames be 16 byte aligned.
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  // When there is a trap handler on the stack, e.g. _sigtramp in userland
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  // code, we've seen that the stack pointer is often not aligned properly
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  // before the handler is invoked.  This means that lldb will stop the unwind
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  // early -- before the function which caused the trap.
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  //
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  // To work around this, we relax that alignment to be just word-size
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  // (4-bytes).
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  // Allowing the trap handlers for user space would be easy (_sigtramp) but
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  // in other environments there can be a large number of different functions
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  // involved in async traps.
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  // ToDo: When __m256 arguments are passed then stack frames should be
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  // 32 byte aligned. Decide what to do for 32 byte alignment checking
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  bool CallFrameAddressIsValid(lldb::addr_t cfa) override {
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    // Make sure the stack call frame addresses are 4 byte aligned
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    if (cfa & (4ull - 1ull))
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      return false; // Not 4 byte aligned
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    if (cfa == 0)
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      return false; // Zero is not a valid stack address
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    return true;
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  }
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  bool CodeAddressIsValid(lldb::addr_t pc) override {
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    // Check whether the address is a valid 32 bit address
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    return (pc <= UINT32_MAX);
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  }
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  // Static Functions
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  static void Initialize();
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  static void Terminate();
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  static lldb::ABISP CreateInstance(lldb::ProcessSP process_sp, const lldb_private::ArchSpec &arch);
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  // PluginInterface protocol
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  static llvm::StringRef GetPluginNameStatic() { return "sysv-i386"; }
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  llvm::StringRef GetPluginName() override { return GetPluginNameStatic(); }
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protected:
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  lldb::ValueObjectSP
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  GetReturnValueObjectSimple(lldb_private::Thread &thread,
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                             lldb_private::CompilerType &ast_type) const;
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  bool RegisterIsCalleeSaved(const lldb_private::RegisterInfo *reg_info);
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private:
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  using ABIX86_i386::ABIX86_i386; // Call CreateInstance instead.
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};
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#endif // LLDB_SOURCE_PLUGINS_ABI_X86_ABISYSV_I386_H