Make ObjectFileMachO work on non-darwin platforms

[labath]

Summary

Before this patch we were unable to write cross-platform MachO tests
because the parsing code did not compile on other platforms. The reason
for that was that ObjectFileMachO depended on
RegisterContextDarwin_arm(64)? (presumably for core file parsing) and
the two Register Context classes uses constants from the system headers
(KERN_SUCCESS, KERN_INVALID_ARGUMENT).

As far as I can tell, these two files don't actually interact with the
darwin kernel -- they are used only in ObjectFileMachO and MacOSX-Kernel
process plugin (even though it has "kernel" in the name, this one
communicates with it via network packets and not syscalls). So there is
no good reason to use os-specific error codes here. In fact, the
RegisterContextDarwin_i386/x86_64 classes and the code which uses them
already use 0/-1 constants for these purposes, so changing the arm
context to do the same makes the code more consistent.

This is the only change necessary (apart from build system glue) to make
ObjectFileMachO work on other platforms. To demonstrate that, I remove
REQUIRES:darwin from our (only) cross-platform mach-o test.

[aprantl]

source/Plugins/Process/Utility/RegisterContextDarwin_arm.cpp

1037 ↗

(On Diff #147029)

Could we keep this as a local constant?
perhaps with an #ifndef KERN_INVALID_ARGUMENT clause?

[labath]

source/Plugins/Process/Utility/RegisterContextDarwin_arm.cpp

1037 ↗

(On Diff #147029)

We could. I didn't do that originally, as RegisterContextDarwin_x86_64::WriteGPR() looks exactly like this function, and it uses -1 already, but that works for me as well.

[jasonmolenda]

Thanks for untangling this Pavel, I hadn't noticed we weren't building this plugin for non-darwin systems. I'd agree with Adrian's comment that we should have a constants like LLDB_KERNEL_SUCCESS / LLDB_KERNEL_INVALID_ARGUMENT, I think the place where -1 was being returned currently would be considered incorrect (it's probably my fault for all I know ;)

[aprantl]

Does that mean we can now also remove the #ifdef APPLE from the objectfile unit tests?

[labath]

In D46934#1101963, @aprantl wrote:

Does that mean we can now also remove the #ifdef APPLE from the objectfile unit tests?

Which ones do you mean? I wasn't aware we had any. The thing I know of, which would be interesting to enable is the MachO core file tests. This can't be done yet because the respective process plugin is apple-only, but I haven't looked at what it would take to enable it everywhere.

[labath]

This is the version with new symbolic constants. I put them in a new file, as I
couldn't think of a better place for them.

I didn't want to put them in a too generic place as I don't think we should
encourage their use (we should convert error to one of our standard errors types
as soon as possible). On the other hand, they are used in two files, so they
can't be internal to a compilation unit. There wasn't anything reasonable in the
overlap of the existing includes of the two files, so I created a new file
instead.

[aprantl]

source/Plugins/Process/Utility/RegisterContextDarwinConstants.h

18 ↗

(On Diff #147286)

I think I would prefer

#ifndef KERN_INVALID_ARGUMENT
#define KERN_INVALID_ARGUMENT 4
#endif

over renaming the constant. I think that that is less confusing to read and we use that pattern in other places in LLDB, too.

[aprantl]

In D46934#1102867, @labath wrote:

In D46934#1101963, @aprantl wrote:

Does that mean we can now also remove the #ifdef APPLE from the objectfile unit tests?

Which ones do you mean? I wasn't aware we had any. The thing I know of, which would be interesting to enable is the MachO core file tests. This can't be done yet because the respective process plugin is apple-only, but I haven't looked at what it would take to enable it everywhere.

Sorry, I was confused. I was thinking about the HostInfoMacOSX class unit test which I added at the same time and somehow the two got conflated in my memory.

[labath]

• Use #ifndef approach for handling the constants.

lldb/trunk/lit/Modules/lc_version_min.yaml

 # RUN: yaml2obj %s > %t.out
 # RUN: lldb-test symbols %t.out | FileCheck %s
-# REQUIRES: darwin
+
 # Test that the deployment target is parsed from the load commands.
 # CHECK: x86_64-apple-macosx10.9.0
 --- !mach-o
 FileHeader:      
   magic:           0xFEEDFACF
   cputype:         0x01000007
   cpusubtype:      0x80000003
   filetype:        0x00000002

lldb/trunk/source/Initialization/CMakeLists.txt

-if ( CMAKE_SYSTEM_NAME MATCHES "Darwin" )
-  list(APPEND EXTRA_PLUGINS lldbPluginObjectFileMachO)
-endif()
-
 if ( CMAKE_SYSTEM_NAME MATCHES "Linux|Android|FreeBSD|NetBSD" )
   list(APPEND EXTRA_PLUGINS lldbPluginProcessPOSIX)
 endif()
 
 if ( CMAKE_SYSTEM_NAME MATCHES "Windows" )
   list(APPEND EXTRA_PLUGINS lldbPluginProcessWindowsCommon)
 endif ()
 
 add_lldb_library(lldbInitialization
   SystemInitializerCommon.cpp
   SystemInitializer.cpp
   SystemLifetimeManager.cpp
 
   LINK_LIBS
     lldbCore
     lldbHost
     lldbPluginInstructionARM
     lldbPluginInstructionMIPS
     lldbPluginInstructionMIPS64
     lldbPluginObjectContainerBSDArchive
     lldbPluginObjectContainerMachOArchive
     lldbPluginObjectFileELF
+    lldbPluginObjectFileMachO
     lldbPluginObjectFilePECOFF
     lldbPluginProcessGDBRemote
     ${EXTRA_PLUGINS}
     ${LLDB_SYSTEM_LIBS}
   LINK_COMPONENTS
     Support
   )

lldb/trunk/source/Initialization/SystemInitializerCommon.cpp

 #include "Plugins/ObjectContainer/Universal-Mach-O/ObjectContainerUniversalMachO.h"
 #include "Plugins/ObjectFile/ELF/ObjectFileELF.h"
 #include "Plugins/ObjectFile/PECOFF/ObjectFilePECOFF.h"
 #include "Plugins/Process/gdb-remote/ProcessGDBRemoteLog.h"
 #include "lldb/Host/Host.h"
 #include "lldb/Host/HostInfo.h"
 #include "lldb/Utility/Log.h"
 #include "lldb/Utility/Timer.h"
-
-#if defined(__APPLE__)
 #include "Plugins/ObjectFile/Mach-O/ObjectFileMachO.h"
-#endif
 
 #if defined(__linux__) || defined(__FreeBSD__) || defined(__NetBSD__)
 #include "Plugins/Process/POSIX/ProcessPOSIXLog.h"
 #endif
 
 #if defined(_MSC_VER)
 #include "Plugins/Process/Windows/Common/ProcessWindowsLog.h"
 #include "lldb/Host/windows/windows.h"
#endif
   static Timer::Category func_cat(LLVM_PRETTY_FUNCTION);
   Timer scoped_timer(func_cat, LLVM_PRETTY_FUNCTION);
 
   process_gdb_remote::ProcessGDBRemoteLog::Initialize();
 
   // Initialize plug-ins
   ObjectContainerBSDArchive::Initialize();
   ObjectFileELF::Initialize();
+  ObjectFileMachO::Initialize();
   ObjectFilePECOFF::Initialize();
 
   EmulateInstructionARM::Initialize();
   EmulateInstructionMIPS::Initialize();
   EmulateInstructionMIPS64::Initialize();
 
   //----------------------------------------------------------------------
   // Apple/Darwin hosted plugins
   //----------------------------------------------------------------------
   ObjectContainerUniversalMachO::Initialize();
 
-#if defined(__APPLE__)
-  ObjectFileMachO::Initialize();
-#endif
 #if defined(__linux__) || defined(__FreeBSD__) || defined(__NetBSD__)
   ProcessPOSIXLog::Initialize();
 #endif
 #if defined(_MSC_VER)
   ProcessWindowsLog::Initialize();
 #endif
 }
 
 void SystemInitializerCommon::Terminate() {
   static Timer::Category func_cat(LLVM_PRETTY_FUNCTION);
   Timer scoped_timer(func_cat, LLVM_PRETTY_FUNCTION);
   ObjectContainerBSDArchive::Terminate();
   ObjectFileELF::Terminate();
+  ObjectFileMachO::Terminate();
   ObjectFilePECOFF::Terminate();
 
   EmulateInstructionARM::Terminate();
   EmulateInstructionMIPS::Terminate();
   EmulateInstructionMIPS64::Terminate();
 
   ObjectContainerUniversalMachO::Terminate();
-#if defined(__APPLE__)
-  ObjectFileMachO::Terminate();
-#endif
 
 #if defined(_MSC_VER)
   ProcessWindowsLog::Terminate();
 #endif
 
   HostInfo::Terminate();
   Log::DisableAllLogChannels();
 }

lldb/trunk/source/Plugins/Process/Utility/RegisterContextDarwinConstants.h

+//===-- RegisterContextDarwinConstants.h ------------------------*- C++ -*-===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef LLDB_REGISTERCONTEXTDARWINCONSTANTS_H
+#define LLDB_REGISTERCONTEXTDARWINCONSTANTS_H
+
+namespace lldb_private {
+
+/// Constants returned by various RegisterContextDarwin_*** functions.
+#ifndef KERN_SUCCESS
+#define KERN_SUCCESS 0
+#endif
+
+#ifndef KERN_INVALID_ARGUMENT
+#define KERN_INVALID_ARGUMENT 4
+#endif
+
+} // namespace lldb_private
+
+#endif // LLDB_REGISTERCONTEXTDARWINCONSTANTS_H

lldb/trunk/source/Plugins/Process/Utility/RegisterContextDarwin_arm.cpp

 //===-- RegisterContextDarwin_arm.cpp ---------------------------*- C++ -*-===//
 //
 //                     The LLVM Compiler Infrastructure
 //
 // This file is distributed under the University of Illinois Open Source
 // License. See LICENSE.TXT for details.
 //
 //===----------------------------------------------------------------------===//
 
-#if defined(__APPLE__)
-
 #include "RegisterContextDarwin_arm.h"
-
-// C Includes
-#include <mach/mach_types.h>
-#include <mach/thread_act.h>
+#include "RegisterContextDarwinConstants.h"
 
 // C++ Includes
 // Other libraries and framework includes
 #include "lldb/Core/RegisterValue.h"
 #include "lldb/Core/Scalar.h"
 #include "lldb/Utility/DataBufferHeap.h"
 #include "lldb/Utility/DataExtractor.h"
 #include "lldb/Utility/Endian.h"
if (hw_index < num_hw_points) {
       kret = WriteDBG();
 
       if (kret == KERN_SUCCESS)
         return true;
     }
   }
   return false;
 }
-
-#endif

lldb/trunk/source/Plugins/Process/Utility/RegisterContextDarwin_arm64.cpp

 //===-- RegisterContextDarwin_arm64.cpp ---------------------------*- C++
 //-*-===//
 //
 //                     The LLVM Compiler Infrastructure
 //
 // This file is distributed under the University of Illinois Open Source
 // License. See LICENSE.TXT for details.
 //
 //===----------------------------------------------------------------------===//
 
-#if defined(__APPLE__)
-
 #include "RegisterContextDarwin_arm64.h"
-
-// C Includes
-#include <mach/mach_types.h>
-#include <mach/thread_act.h>
-#include <sys/sysctl.h>
+#include "RegisterContextDarwinConstants.h"
 
 // C++ Includes
 // Other libraries and framework includes
 #include "lldb/Core/RegisterValue.h"
 #include "lldb/Core/Scalar.h"
 #include "lldb/Target/Process.h"
 #include "lldb/Target/Thread.h"
 #include "lldb/Utility/DataBufferHeap.h"
if (hw_index < num_hw_points) {
       kret = WriteDBG();
 
       if (kret == KERN_SUCCESS)
         return true;
     }
   }
   return false;
 }
-
-#endif