Bug 1485716 - part 3 - add aarch64 windows support to the profiler; r=mstange

Frame pointers are enabled in Windows code always, and in our code by
default after the first patch in this series.

tools/profiler/core/PlatformMacros.h

@@ -23,6 +23,7 @@
 #undef GP_PLAT_amd64_darwin
 #undef GP_PLAT_x86_windows
 #undef GP_PLAT_amd64_windows
+#undef GP_PLAT_arm64_windows
 
 #undef GP_ARCH_x86
 #undef GP_ARCH_amd64
@@ -95,6 +96,11 @@
 # define GP_ARCH_amd64 1
 # define GP_OS_windows 1
 
+#elif defined(_MSC_VER) && defined(_M_ARM64)
+# define GP_PLAT_arm64_windows 1
+# define GP_ARCH_arm64 1
+# define GP_OS_windows 1
+
 #else
 # error "Unsupported platform"
 #endif

tools/profiler/core/platform.cpp

@@ -102,6 +102,12 @@
 # define USE_MOZ_STACK_WALK
 #endif
 
+// AArch64 Win64 builds use frame pointers.
+#if defined(GP_PLAT_arm64_windows)
+# define HAVE_NATIVE_UNWIND
+# define USE_FRAME_POINTER_STACK_WALK
+#endif
+
 // Mac builds only have frame pointers when MOZ_PROFILING is specified, so
 // FramePointerStackWalk() only works in that case. We don't use MozStackWalk()
 // on Mac.