Import LLVM libunwind snapshot revision 256779vendor/llvm-libunwind/libunwind-r256779

From https://llvm.org/svn/llvm-project/libunwind/trunk/

6 files changed, 24 insertions, 2 deletions

diff --git a/src/AddressSpace.hpp b/src/AddressSpace.hpp
index 567cbdad92e2..73013c73ff71 100644
--- a/src/AddressSpace.hpp
+++ b/src/AddressSpace.hpp
@@ -35,7 +35,11 @@ namespace libunwind {
 #include "Registers.hpp"
 
 #if _LIBUNWIND_ARM_EHABI
-#ifdef __linux__
+#if defined(__FreeBSD__)
+
+typedef void *_Unwind_Ptr;
+
+#elif defined(__linux__)
 
 typedef long unsigned int *_Unwind_Ptr;
 extern "C" _Unwind_Ptr __gnu_Unwind_Find_exidx(_Unwind_Ptr addr, int *len);
diff --git a/src/DwarfParser.hpp b/src/DwarfParser.hpp
index 26993c4e0d1b..a19f0510a37b 100644
--- a/src/DwarfParser.hpp
+++ b/src/DwarfParser.hpp
@@ -380,7 +380,9 @@ bool CFI_Parser<A>::parseInstructions(A &addressSpace, pint_t instructions,
     uint64_t length;
     uint8_t opcode = addressSpace.get8(p);
     uint8_t operand;
+#if !defined(_LIBUNWIND_NO_HEAP)
     PrologInfoStackEntry *entry;
+#endif
     ++p;
     switch (opcode) {
     case DW_CFA_nop:
@@ -492,6 +494,7 @@ bool CFI_Parser<A>::parseInstructions(A &addressSpace, pint_t instructions,
         fprintf(stderr, "DW_CFA_register(reg=%" PRIu64 ", reg2=%" PRIu64 ")\n",
                 reg, reg2);
       break;
+#if !defined(_LIBUNWIND_NO_HEAP)
     case DW_CFA_remember_state:
       // avoid operator new, because that would be an upward dependency
       entry = (PrologInfoStackEntry *)malloc(sizeof(PrologInfoStackEntry));
@@ -517,6 +520,7 @@ bool CFI_Parser<A>::parseInstructions(A &addressSpace, pint_t instructions,
       if (logDwarf)
         fprintf(stderr, "DW_CFA_restore_state\n");
       break;
+#endif
     case DW_CFA_def_cfa:
       reg = addressSpace.getULEB128(p, instructionsEnd);
       offset = (int64_t)addressSpace.getULEB128(p, instructionsEnd);
diff --git a/src/UnwindCursor.hpp b/src/UnwindCursor.hpp
index 040d13e92563..90683164ff24 100644
--- a/src/UnwindCursor.hpp
+++ b/src/UnwindCursor.hpp
@@ -114,6 +114,7 @@ typename A::pint_t DwarfFDECache<A>::findFDE(pint_t mh, pint_t pc) {
 template <typename A>
 void DwarfFDECache<A>::add(pint_t mh, pint_t ip_start, pint_t ip_end,
                            pint_t fde) {
+#if !defined(_LIBUNWIND_NO_HEAP)
   _LIBUNWIND_LOG_NON_ZERO(::pthread_rwlock_wrlock(&_lock));
   if (_bufferUsed >= _bufferEnd) {
     size_t oldSize = (size_t)(_bufferEnd - _buffer);
@@ -139,6 +140,7 @@ void DwarfFDECache<A>::add(pint_t mh, pint_t ip_start, pint_t ip_end,
   }
 #endif
   _LIBUNWIND_LOG_NON_ZERO(::pthread_rwlock_unlock(&_lock));
+#endif
 }
 
 template <typename A>
diff --git a/src/UnwindRegistersSave.S b/src/UnwindRegistersSave.S
index 1275c2a16175..f84b7114f777 100644
--- a/src/UnwindRegistersSave.S
+++ b/src/UnwindRegistersSave.S
@@ -87,6 +87,15 @@ DEFINE_LIBUNWIND_FUNCTION(unw_getcontext)
   xorl  %eax, %eax    # return UNW_ESUCCESS
   ret
 
+# elif defined(__mips__)
+
+#
+# extern int unw_getcontext(unw_context_t* thread_state)
+#
+# Just trap for the time being.
+DEFINE_LIBUNWIND_FUNCTION(unw_getcontext)
+  teq $0, $0
+
 #elif defined(__ppc__)
 
 ;
diff --git a/src/config.h b/src/config.h
index 9b246347a851..ecc0a6b4465d 100644
--- a/src/config.h
+++ b/src/config.h
@@ -41,7 +41,8 @@
 
   #define _LIBUNWIND_BUILD_ZERO_COST_APIS (defined(__i386__) || \
                                            defined(__x86_64__) || \
-                                           defined(__arm64__))
+                                           defined(__arm64__) || \
+                                           defined(__mips__))
   #define _LIBUNWIND_BUILD_SJLJ_APIS      defined(__arm__)
   #define _LIBUNWIND_SUPPORT_FRAME_APIS   (defined(__i386__) || \
                                            defined(__x86_64__))
diff --git a/src/libunwind.cpp b/src/libunwind.cpp
index a23dfcf7677a..f9f32f00ece2 100644
--- a/src/libunwind.cpp
+++ b/src/libunwind.cpp
@@ -64,6 +64,8 @@ _LIBUNWIND_EXPORT int unw_init_local(unw_cursor_t *cursor,
 #elif defined(__or1k__)
   new ((void *)cursor) UnwindCursor<LocalAddressSpace, Registers_or1k>(
                                  context, LocalAddressSpace::sThisAddressSpace);
+#elif defined(__mips__)
+#warning The MIPS architecture is not supported.
 #else
 #error Architecture not supported
 #endif