Store FP instead of SP in the exit info when transitioning from Dart to C++.

runtime/vm/stub_code_arm.cc

Index: runtime/vm/stub_code_arm.cc
diff --git a/runtime/vm/stub_code_arm.cc b/runtime/vm/stub_code_arm.cc
index 1d438ec16e8310e8582d7a0c8e2d7d27e6bc049a..4e151b6254891ff416a1efa77ecd9e40665ab8fe 100644
--- a/runtime/vm/stub_code_arm.cc
+++ b/runtime/vm/stub_code_arm.cc
@@ -52,7 +52,7 @@ void StubCode::GenerateCallToRuntimeStub(Assembler* assembler) {
 
   // Save exit frame information to enable stack walking as we are about
   // to transition to Dart VM C++ code.
-  __ StoreToOffset(kWord, SP, R9, Isolate::top_exit_frame_info_offset());
+  __ StoreToOffset(kWord, FP, R9, Isolate::top_exit_frame_info_offset());
 
 #if defined(DEBUG)
   { Label ok;
@@ -151,7 +151,7 @@ void StubCode::GenerateCallNativeCFunctionStub(Assembler* assembler) {
 
   // Save exit frame information to enable stack walking as we are about
   // to transition to native code.
-  __ StoreToOffset(kWord, SP, R9, Isolate::top_exit_frame_info_offset());
+  __ StoreToOffset(kWord, FP, R9, Isolate::top_exit_frame_info_offset());
 
 #if defined(DEBUG)
   { Label ok;
@@ -244,7 +244,7 @@ void StubCode::GenerateCallBootstrapCFunctionStub(Assembler* assembler) {
 
   // Save exit frame information to enable stack walking as we are about
   // to transition to native code.
-  __ StoreToOffset(kWord, SP, R9, Isolate::top_exit_frame_info_offset());
+  __ StoreToOffset(kWord, FP, R9, Isolate::top_exit_frame_info_offset());
 
 #if defined(DEBUG)
   { Label ok;