Introduce a native-only unwinder build.
Currently libunwind is built to support cross-unwinding [1] by default, which
requires the buffers unw_context_t and unw_cursor_t to be large enough to hold
the vritual register set (VRS) of any supported architecture. This is not
desirable for some platforms where the stack usage of the unwinder needs
to be kept to a minimum (e.g. bare-metal targets). The current patch introduces
a native-only (-DLIBUNWIND_ENABLE_CROSS_UNWINDING=OFF) unwinder variant that
adopts strict sizes for the buffers unw_context_t and unw_cursor_t depending
on the target architecture.
[1] http://www.nongnu.org/libunwind/man/libunwind(3).html#section_4
Change-Id: I380fff9a56c16a0fc520e3b1d8454a34b4a48373
llvm-svn: 270692
Cr-Mirrored-From: sso://chromium.googlesource.com/_direct/external/github.com/llvm/llvm-project
Cr-Mirrored-Commit: 54387eef0772619db3aa2e08db3de5d690fe32c7
diff --git a/src/libunwind.cpp b/src/libunwind.cpp
index f9f32f0..95f2dc0 100644
--- a/src/libunwind.cpp
+++ b/src/libunwind.cpp
@@ -45,30 +45,27 @@
_LIBUNWIND_TRACE_API("unw_init_local(cursor=%p, context=%p)\n",
static_cast<void *>(cursor),
static_cast<void *>(context));
- // Use "placement new" to allocate UnwindCursor in the cursor buffer.
#if defined(__i386__)
- new ((void *)cursor) UnwindCursor<LocalAddressSpace, Registers_x86>(
- context, LocalAddressSpace::sThisAddressSpace);
+# define REGISTER_KIND Registers_x86
#elif defined(__x86_64__)
- new ((void *)cursor) UnwindCursor<LocalAddressSpace, Registers_x86_64>(
- context, LocalAddressSpace::sThisAddressSpace);
+# define REGISTER_KIND Registers_x86_64
#elif defined(__ppc__)
- new ((void *)cursor) UnwindCursor<LocalAddressSpace, Registers_ppc>(
- context, LocalAddressSpace::sThisAddressSpace);
-#elif defined(__arm64__) || defined(__aarch64__)
- new ((void *)cursor) UnwindCursor<LocalAddressSpace, Registers_arm64>(
- context, LocalAddressSpace::sThisAddressSpace);
+# define REGISTER_KIND Registers_ppc
+#elif defined(__aarch64__)
+# define REGISTER_KIND Registers_arm64
#elif _LIBUNWIND_ARM_EHABI
- new ((void *)cursor) UnwindCursor<LocalAddressSpace, Registers_arm>(
- context, LocalAddressSpace::sThisAddressSpace);
+# define REGISTER_KIND Registers_arm
#elif defined(__or1k__)
- new ((void *)cursor) UnwindCursor<LocalAddressSpace, Registers_or1k>(
- context, LocalAddressSpace::sThisAddressSpace);
+# define REGISTER_KIND Registers_or1k
#elif defined(__mips__)
-#warning The MIPS architecture is not supported.
+# warning The MIPS architecture is not supported.
#else
-#error Architecture not supported
+# error Architecture not supported
#endif
+ // Use "placement new" to allocate UnwindCursor in the cursor buffer.
+ new ((void *)cursor) UnwindCursor<LocalAddressSpace, REGISTER_KIND>(
+ context, LocalAddressSpace::sThisAddressSpace);
+#undef REGISTER_KIND
AbstractUnwindCursor *co = (AbstractUnwindCursor *)cursor;
co->setInfoBasedOnIPRegister();