PAL_VirtualUnwindOutOfProc for MacOS (dotnet#39213)

PAL_VirtualUnwindOutOfProc for MacOS

Add MacOS compact unwind section parsing (__unwind_info) and stepping: SearchCompactEncodingSection, SearchDwarfSection, GetProcInfo, StepWithCompactEncoding*.

Add back some (from a previous commit) of the dwarf unwind info parsing functions to use for the dwarf unwind info (__eh_frame section): ReadValue*, ReadULEB128, ReadSLEB128, ReadEncodedPointer, ParseCie, ExtractFde, ExtractProcInfoFromFde. These functions were used and fairly well tested in 3.x.

Build libunwind8 source on MacOS for those dwarf unwind info cases.

The methoddesc's enum memory region code needed add more of the code version manager's data to the coredump.

src/coreclr/src/debug/daccess/dacfn.cpp

@@ -268,7 +268,7 @@ DacVirtualUnwind(ULONG32 threadId, PT_CONTEXT context, PT_KNONVOLATILE_CONTEXT_P
         memset(contextPointers, 0, sizeof(T_KNONVOLATILE_CONTEXT_POINTERS));
     }
 
-    HRESULT hr = S_OK;
+    HRESULT hr = E_NOINTERFACE;
 
 #ifdef FEATURE_DATATARGET4
     ReleaseHolder<ICorDebugDataTarget4> dt;
@@ -277,9 +277,12 @@ DacVirtualUnwind(ULONG32 threadId, PT_CONTEXT context, PT_KNONVOLATILE_CONTEXT_P
     {
         hr = dt->VirtualUnwind(threadId, sizeof(CONTEXT), (BYTE*)context);
     }
-    else
 #endif
+
+    if (hr == E_NOINTERFACE || hr == E_NOTIMPL)
     {
+        hr = S_OK;
+
         SIZE_T baseAddress = DacGlobalBase();
         if (baseAddress == 0 || !PAL_VirtualUnwindOutOfProc(context, contextPointers, baseAddress, DacReadAllAdapter))
         {

src/coreclr/src/dlls/mscordac/CMakeLists.txt

@@ -179,6 +179,12 @@ if(CLR_CMAKE_HOST_WIN32 AND CLR_CMAKE_TARGET_UNIX)
     )
 endif(CLR_CMAKE_HOST_WIN32 AND CLR_CMAKE_TARGET_UNIX)
 
+if(CLR_CMAKE_HOST_OSX)
+    list(APPEND COREDAC_LIBRARIES
+        coreclrpal_dac
+    )
+endif(CLR_CMAKE_HOST_OSX)
+
 target_link_libraries(mscordaccore PRIVATE ${COREDAC_LIBRARIES})
 
 # Create the DAC module index header file containing the DAC build id

src/coreclr/src/pal/src/CMakeLists.txt

@@ -18,6 +18,8 @@ if(NOT CLR_CMAKE_USE_SYSTEM_LIBUNWIND)
   add_subdirectory(libunwind)
 elseif(NOT CLR_CMAKE_TARGET_OSX)
   find_unwind_libs(UNWIND_LIBS)
+else()
+  add_subdirectory(libunwind)
 endif(NOT CLR_CMAKE_USE_SYSTEM_LIBUNWIND)
 
 include(configure.cmake)
@@ -131,7 +133,6 @@ set(SOURCES
   debug/debug.cpp
   exception/seh.cpp
   exception/signal.cpp
-  exception/remote-unwind.cpp
   file/directory.cpp
   file/file.cpp
   file/filetime.cpp
@@ -214,6 +215,12 @@ set(SOURCES
   thread/threadsusp.cpp
 )
 
+if(NOT CLR_CMAKE_TARGET_OSX)
+  list(APPEND SOURCES
+     exception/remote-unwind.cpp
+  )
+endif(NOT CLR_CMAKE_TARGET_OSX)
+
 if(NOT CLR_CMAKE_USE_SYSTEM_LIBUNWIND)
   set(LIBUNWIND_OBJECTS $<TARGET_OBJECTS:libunwind>)
 endif(NOT CLR_CMAKE_USE_SYSTEM_LIBUNWIND)
@@ -226,6 +233,29 @@ add_library(coreclrpal
   ${LIBUNWIND_OBJECTS}
 )
 
+# Build separate pal library for DAC (addition to regular pal library)
+if(CLR_CMAKE_TARGET_OSX)
+  set(LIBUNWIND_DAC_OBJECTS $<TARGET_OBJECTS:libunwind_dac>)
+
+  add_library(coreclrpal_dac STATIC
+    exception/remote-unwind.cpp
+    ${LIBUNWIND_DAC_OBJECTS}
+  )
+
+  target_compile_definitions(coreclrpal_dac PUBLIC 
+    "-D_XOPEN_SOURCE"
+    "-DUNW_REMOTE_ONLY"
+  )
+
+  target_include_directories(coreclrpal_dac PUBLIC 
+    ${CMAKE_CURRENT_SOURCE_DIR}/libunwind/include
+    ${CMAKE_CURRENT_SOURCE_DIR}/libunwind/include/tdep
+    ${CMAKE_CURRENT_BINARY_DIR}
+    ${CMAKE_CURRENT_BINARY_DIR}/libunwind/include
+    ${CMAKE_CURRENT_BINARY_DIR}/libunwind/include/tdep
+  )
+endif(CLR_CMAKE_TARGET_OSX)
+
 # There is only one function exported in 'tracepointprovider.cpp' namely 'PAL_InitializeTracing',
 # which is guarded with '#if defined(__linux__)'. On macOS, Xcode issues the following warning:
 #
@@ -309,6 +339,5 @@ if(FEATURE_EVENT_TRACE)
   add_subdirectory(eventprovider)
 endif(FEATURE_EVENT_TRACE)
 
-
 # Install the static PAL library for VS
 _install (TARGETS coreclrpal DESTINATION lib)