Use LLVM libunwind for stack unwinding on Unix

This change replaces external libunwind usage on Unix by a copy of the LLVM libunwind.
It also modifies libunwind to support reporting register location and implements
the unw_get_save_loc API to get this location.
For now, only memory locations are supported (register locations are not).

Documentation/prerequisites-for-building.md

@@ -13,7 +13,7 @@ PowerShell also needs to be available from the PATH environment variable (it's t
 Install basic dependency packages:
 
 ```
-sudo apt-get install cmake llvm-3.5 clang-3.5 lldb-3.6 lldb-3.6-dev libunwind8 libunwind8-dev liblttng-ust liblttng-ust-dev uuid uuid-dev
+sudo apt-get install cmake llvm-3.5 clang-3.5 lldb-3.6 lldb-3.6-dev liblttng-ust liblttng-ust-dev uuid uuid-dev
 ```
 
 # Mac OSX (10.10+)

THIRD-PARTY-NOTICES

@@ -0,0 +1,59 @@
+.NET Core uses third-party libraries or other resources that may be
+distributed under licenses different than the .NET Core software.
+
+Attributions and licence notices for test cases originally authored by
+third parties can be found in the respective test directories.
+
+In the event that we accidentally failed to list a required notice, please
+bring it to our attention. Post an issue or email us:
+
+           [email protected]
+
+The attached notices are provided for information only.
+
+License notice for The LLVM Compiler Infrastructure
+---------------------------------------------------
+==============================================================================
+LLVM Release License
+==============================================================================
+University of Illinois/NCSA
+Open Source License
+
+Copyright (c) 2003-2015 University of Illinois at Urbana-Champaign.
+All rights reserved.
+
+Developed by:
+
+    LLVM Team
+
+    University of Illinois at Urbana-Champaign
+
+    http://llvm.org
+
+Permission is hereby granted, free of charge, to any person obtaining a copy of
+this software and associated documentation files (the "Software"), to deal with
+the Software without restriction, including without limitation the rights to
+use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies
+of the Software, and to permit persons to whom the Software is furnished to do
+so, subject to the following conditions:
+
+    * Redistributions of source code must retain the above copyright notice,
+      this list of conditions and the following disclaimers.
+
+    * Redistributions in binary form must reproduce the above copyright notice,
+      this list of conditions and the following disclaimers in the
+      documentation and/or other materials provided with the distribution.
+
+    * Neither the names of the LLVM Team, University of Illinois at
+      Urbana-Champaign, nor the names of its contributors may be used to
+      endorse or promote products derived from this Software without specific
+      prior written permission.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS
+FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL THE
+CONTRIBUTORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS WITH THE
+SOFTWARE.
+

src/BuildIntegration/Microsoft.NETCore.Native.Unix.targets

@@ -59,7 +59,6 @@ See the LICENSE file in the project root for more information.
       <LinkerArg Include="-ldl" />
       <LinkerArg Include="-lm" />
       <LinkerArg Include="-lrt" Condition="'$(TargetOS)' != 'OSX'" />
-      <LinkerArg Include="-lunwind-x86_64" Condition="'$(TargetOS)' != 'OSX'" />
     </ItemGroup>
 
     <MakeDir Directories="$([System.IO.Path]::GetDirectoryName($(NativeBinary)))" />

src/Native/Runtime/CMakeLists.txt

@@ -73,6 +73,9 @@ if(WIN32)
   list(APPEND COMMON_RUNTIME_SOURCES
     windows/PalRedhawkCommon.cpp
     windows/PalRedhawkMinWin.cpp
+  )
+
+  list(APPEND FULL_RUNTIME_SOURCES 
     windows/CoffNativeCodeManager.cpp
   )
 
@@ -88,14 +91,32 @@ if(WIN32)
 else()
 
   include_directories(unix)
+  include_directories(../libunwind/include)
+
+  # Disable building _Unwind_XXX style APIs of libunwind, since we don't use them.
+  add_definitions(-D_LIBUNWIND_DISABLE_ZERO_COST_APIS=1)
+
+  # Compile unwinding only for the current compilation target architecture
+  add_definitions(-D_LIBUNWIND_IS_NATIVE_ONLY)
 
   list(APPEND COMMON_RUNTIME_SOURCES
-    unix/HardwareExceptions.cpp
     unix/PalRedhawkUnix.cpp
+  )
+
+  list(APPEND FULL_RUNTIME_SOURCES
+    unix/HardwareExceptions.cpp
     unix/UnixContext.cpp
     unix/UnixNativeCodeManager.cpp
+    ../libunwind/src/Unwind-EHABI.cpp
+    ../libunwind/src/libunwind.cpp
   )
 
+  if(CLR_CMAKE_PLATFORM_DARWIN)
+    list(APPEND FULL_RUNTIME_SOURCES
+      ../libunwind/src/Unwind_AppleExtras.cpp
+    )
+  endif()
+
   if(CLR_CMAKE_PLATFORM_ARCH_AMD64)
     set(ARCH_SOURCES_DIR amd64)
     set(ASM_SUFFIX S)
@@ -107,6 +128,10 @@ else()
     set(ASM_SUFFIX S)
   endif()
 
+  list(APPEND RUNTIME_SOURCES_ARCH_ASM
+    ../libunwind/src/UnwindRegistersRestore.S
+    ../libunwind/src/UnwindRegistersSave.S
+  )
 endif()
 
 list(APPEND RUNTIME_SOURCES_ARCH_ASM

src/Native/Runtime/startup.cpp

@@ -70,13 +70,13 @@ bool InitDLL(HANDLE hPalInstance)
     if (!RestrictedCallouts::Initialize())
         return false;
 
-#ifndef APP_LOCAL_RUNTIME
+#if !defined(APP_LOCAL_RUNTIME) && !defined(USE_PORTABLE_HELPERS)
 #ifndef PLATFORM_UNIX
     PalAddVectoredExceptionHandler(1, RhpVectoredExceptionHandler);
 #else
     PalSetHardwareExceptionHandler(RhpHardwareExceptionHandler);
 #endif
-#endif
+#endif // !APP_LOCAL_RUNTIME && !USE_PORTABLE_HELPERS
 
     //
     // init per-instance state

src/Native/Runtime/unix/PalRedhawkUnix.cpp

@@ -443,12 +443,12 @@ REDHAWK_PALEXPORT bool REDHAWK_PALAPI PalInit()
     {
         return false;
     }
-
+#ifndef USE_PORTABLE_HELPERS
     if (!InitializeHardwareExceptionHandling())
     {
         return false;
     }
-
+#endif // !USE_PORTABLE_HELPERS
     int status = pthread_key_create(&g_threadKey, TlsObjectDestructor);
     if (status != 0)
     {

src/Native/Runtime/unix/UnixContext.cpp

@@ -11,10 +11,6 @@
 #include "regdisplay.h"
 #include "config.h"
 
-#if !HAVE_LIBUNWIND_H
-#error Don't know how to unwind on this platform
-#endif
-
 #include <libunwind.h>
 
 #if HAVE_UCONTEXT_T
@@ -201,56 +197,6 @@
 
 #endif // __APPLE__
 
-#if UNWIND_CONTEXT_IS_UCONTEXT_T
-
-#if defined(_AMD64_)
-#define ASSIGN_UNWIND_REGS     \
-    ASSIGN_REG(Rip, IP)        \
-    ASSIGN_REG(Rsp, SP)        \
-    ASSIGN_REG_PTR(Rbp, Rbp)   \
-    ASSIGN_REG_PTR(Rbx, Rbx)   \
-    ASSIGN_REG_PTR(R12, R12)   \
-    ASSIGN_REG_PTR(R13, R13)   \
-    ASSIGN_REG_PTR(R14, R14)   \
-    ASSIGN_REG_PTR(R15, R15)
-#elif defined(_ARM64_)
-#define ASSIGN_UNWIND_REGS     \
-    ASSIGN_REG(Pc, IP)
-    // ASSIGN_REG(Sp, SP)         \
-    // ASSIGN_REG_PTR(Fp, FP)     \
-    // ASSIGN_REG_PTR(Lr, LR)     \
-    // ASSIGN_REG_PTR(X19, X19)   \
-    // ASSIGN_REG_PTR(X20, X20)   \
-    // ASSIGN_REG_PTR(X21, X21)   \
-    // ASSIGN_REG_PTR(X22, X22)   \
-    // ASSIGN_REG_PTR(X23, X23)   \
-    // ASSIGN_REG_PTR(X24, X24)   \
-    // ASSIGN_REG_PTR(X25, X25)   \
-    // ASSIGN_REG_PTR(X26, X26)   \
-    // ASSIGN_REG_PTR(X27, X27)   \
-    // ASSIGN_REG_PTR(X28, X28)
-#else
-#error unsupported architecture
-#endif
-
-// Convert REGDISPLAY to unw_context_t
-static void RegDisplayToUnwindContext(REGDISPLAY* regDisplay, unw_context_t *unwContext)
-{
-#define ASSIGN_REG(regName1, regName2) \
-    MCREG_##regName1(unwContext->uc_mcontext) = regDisplay->regName2;
-
-#define ASSIGN_REG_PTR(regName1, regName2) \
-    if (regDisplay->p##regName2 != NULL) \
-        MCREG_##regName1(unwContext->uc_mcontext) = *(regDisplay->p##regName2);
-
-    ASSIGN_UNWIND_REGS
-
-#undef ASSIGN_REG
-#undef ASSIGN_REG_PTR
-}
-
-#else // UNWIND_CONTEXT_IS_UCONTEXT_T
-
 // Update unw_context_t from REGDISPLAY
 static void RegDisplayToUnwindContext(REGDISPLAY* regDisplay, unw_context_t *unwContext)
 {
@@ -309,20 +255,17 @@ static void RegDisplayToUnwindCursor(REGDISPLAY* regDisplay, unw_cursor_t *curso
 #undef ASSIGN_REG_PTR
 #endif // _AMD64_
 }
-#endif // UNWIND_CONTEXT_IS_UCONTEXT_T
 
 // Initialize unw_cursor_t and unw_context_t from REGDISPLAY
 bool InitializeUnwindContextAndCursor(REGDISPLAY* regDisplay, unw_cursor_t* cursor, unw_context_t* unwContext)
 {
     int st;
 
-#if !UNWIND_CONTEXT_IS_UCONTEXT_T
     st = unw_getcontext(unwContext);
     if (st < 0)
     {
         return false;
     }
-#endif
 
     RegDisplayToUnwindContext(regDisplay, unwContext);
 
@@ -332,18 +275,15 @@ bool InitializeUnwindContextAndCursor(REGDISPLAY* regDisplay, unw_cursor_t* curs
         return false;
     }
 
-#if !UNWIND_CONTEXT_IS_UCONTEXT_T
     // Set the unwind context to the specified windows context
     RegDisplayToUnwindCursor(regDisplay, cursor);
-#endif
 
     return true;
 }
 
 // Update context pointer for a register from the unw_cursor_t.
 static void GetContextPointer(unw_cursor_t *cursor, unw_context_t *unwContext, int reg, PTR_UIntNative *contextPointer)
 {
-#if defined(HAVE_UNW_GET_SAVE_LOC)
     unw_save_loc_t saveLoc;
     unw_get_save_loc(cursor, reg, &saveLoc);
     if (saveLoc.type == UNW_SLT_MEMORY)
@@ -353,10 +293,6 @@ static void GetContextPointer(unw_cursor_t *cursor, unw_context_t *unwContext, i
         if (unwContext == NULL || (pLoc < (PTR_UIntNative)unwContext) || ((PTR_UIntNative)(unwContext + 1) <= pLoc))
             *contextPointer = (PTR_UIntNative)saveLoc.u.addr;
     }
-#else
-    // Returning NULL indicates that we don't have context pointers available
-    *contextPointer = NULL;
-#endif
 }
 
 #if defined(_AMD64_)
@@ -600,7 +536,6 @@ bool VirtualUnwind(REGDISPLAY* pRegisterSet)
         return false;
     }
 
-#if defined(__APPLE__) || defined(__FreeBSD__) || defined(__NetBSD__)  || defined(_ARM64_) || defined(_ARM_)
     // FreeBSD, NetBSD and OSX appear to do two different things when unwinding
     // 1: If it reaches where it cannot unwind anymore, say a
     // managed frame.  It wil return 0, but also update the $pc
@@ -610,7 +545,6 @@ bool VirtualUnwind(REGDISPLAY* pRegisterSet)
     // So we bank the original PC here, so we can compare it after
     // the step
     uintptr_t curPc = pRegisterSet->GetIP();
-#endif
 
     int st = unw_step(&cursor);
     if (st < 0)
@@ -621,13 +555,11 @@ bool VirtualUnwind(REGDISPLAY* pRegisterSet)
     // Update the REGDISPLAY to reflect the unwind
     UnwindCursorToRegDisplay(&cursor, &unwContext, pRegisterSet);
 
-#if defined(__APPLE__) || defined(__FreeBSD__) || defined(__NetBSD__)  || defined(_ARM64_) || defined(_ARM_)
     if (st == 0 && pRegisterSet->GetIP() == curPc)
     {
         // TODO: is this correct for CoreRT? Should we return false instead?
         pRegisterSet->SetIP(0);
     }
-#endif
 
     return true;
 }

src/Native/Runtime/unix/config.h.in

@@ -4,7 +4,6 @@
 #cmakedefine01 HAVE_SYS_VMPARAM_H
 #cmakedefine01 HAVE_MACH_VM_TYPES_H
 #cmakedefine01 HAVE_MACH_VM_PARAM_H
-#cmakedefine01 HAVE_LIBUNWIND_H
 
 #cmakedefine01 HAVE_PTHREAD_ATTR_GET_NP
 #cmakedefine01 HAVE_PTHREAD_GETATTR_NP
@@ -15,14 +14,11 @@
 #cmakedefine01 HAVE_SYSCTL
 #cmakedefine01 HAVE_SYSCONF
 
-#cmakedefine HAVE_UNW_GET_SAVE_LOC
-
 #cmakedefine01 HAVE_GREGSET_T
 #cmakedefine01 HAVE___GREGSET_T
 
 #cmakedefine01 HAVE_SIGINFO_T
 #cmakedefine01 HAVE_UCONTEXT_T
-#cmakedefine01 UNWIND_CONTEXT_IS_UCONTEXT_T
 
 #cmakedefine01 HAVE__SC_PHYS_PAGES
 #cmakedefine01 HAVE__SC_AVPHYS_PAGES

src/Native/Runtime/unix/configure.cmake

@@ -18,7 +18,6 @@ list(APPEND CMAKE_REQUIRED_DEFINITIONS -D_FILE_OFFSET_BITS=64)
 check_include_files(sys/vmparam.h HAVE_SYS_VMPARAM_H)
 check_include_files(mach/vm_types.h HAVE_MACH_VM_TYPES_H)
 check_include_files(mach/vm_param.h HAVE_MACH_VM_PARAM_H)
-check_include_files(libunwind.h HAVE_LIBUNWIND_H)
 
 check_library_exists(pthread pthread_attr_get_np "" HAVE_PTHREAD_ATTR_GET_NP)
 check_library_exists(pthread pthread_getattr_np "" HAVE_PTHREAD_GETATTR_NP)
@@ -29,20 +28,6 @@ check_function_exists(clock_nanosleep HAVE_CLOCK_NANOSLEEP)
 check_function_exists(sysctl HAVE_SYSCTL)
 check_function_exists(sysconf HAVE_SYSCONF)
 
-set(CMAKE_REQUIRED_LIBRARIES unwind unwind-generic)
-check_cxx_source_compiles("
-#include <libunwind.h>
-
-int main(int argc, char **argv) {
-  unw_cursor_t cursor;
-  unw_save_loc_t saveLoc;
-  int reg = UNW_REG_IP;
-  unw_get_save_loc(&cursor, reg, &saveLoc);
-
-  return 0;
-}" HAVE_UNW_GET_SAVE_LOC)
-set(CMAKE_REQUIRED_LIBRARIES)
-
 check_struct_has_member ("ucontext_t" uc_mcontext.gregs[0] ucontext.h HAVE_GREGSET_T)
 check_struct_has_member ("ucontext_t" uc_mcontext.__gregs[0] ucontext.h HAVE___GREGSET_T)
 
@@ -53,19 +38,6 @@ set(CMAKE_EXTRA_INCLUDE_FILES)
 set(CMAKE_EXTRA_INCLUDE_FILES ucontext.h)
 check_type_size(ucontext_t UCONTEXT_T)
 
-check_cxx_source_compiles("
-#include <libunwind.h>
-#include <ucontext.h>
-
-int main(int argc, char **argv)
-{
-        unw_context_t libUnwindContext;
-        ucontext_t uContext;
-
-        libUnwindContext = uContext;
-        return 0;
-}" UNWIND_CONTEXT_IS_UCONTEXT_T)
-
 check_cxx_symbol_exists(_SC_PHYS_PAGES unistd.h HAVE__SC_PHYS_PAGES)
 check_cxx_symbol_exists(_SC_AVPHYS_PAGES unistd.h HAVE__SC_AVPHYS_PAGES)
 
@@ -133,9 +105,4 @@ int main()
   exit(ret);
 }" HAVE_MACH_ABSOLUTE_TIME)
 
-if(NOT HAVE_LIBUNWIND_H)
-  unset(HAVE_LIBUNWIND_H CACHE)
-  message(FATAL_ERROR "Cannot find libunwind. Try installing libunwind8 and libunwind8-dev (or the appropriate packages for your platform)")
-endif()
-
 configure_file(${CMAKE_CURRENT_LIST_DIR}/config.h.in ${CMAKE_CURRENT_BINARY_DIR}/config.h)