Move some isolate state setup from C++ code to JumpToExceptionHandler stub

runtime/vm/stub_code_arm64.cc

Index: runtime/vm/stub_code_arm64.cc
diff --git a/runtime/vm/stub_code_arm64.cc b/runtime/vm/stub_code_arm64.cc
index a4e43e9e59628c1ff615c12390430b2db5a7e9bc..674db2ca764923d7f69451d89a22ef03f448e72f 100644
--- a/runtime/vm/stub_code_arm64.cc
+++ b/runtime/vm/stub_code_arm64.cc
@@ -1819,6 +1819,7 @@ void StubCode::GenerateGetStackPointerStub(Assembler* assembler) {
 // R2: frame_pointer.
 // R3: error object.
 // R4: address of stacktrace object.
+// R5: isolate.
 // Does not return.
 void StubCode::GenerateJumpToExceptionHandlerStub(Assembler* assembler) {
   ASSERT(kExceptionObjectReg == R0);
@@ -1828,6 +1829,12 @@ void StubCode::GenerateJumpToExceptionHandlerStub(Assembler* assembler) {
   __ mov(FP, R2);  // Frame_pointer.
   __ mov(R0, R3);  // Exception object.
   __ mov(R1, R4);  // StackTrace object.
+  __ mov(CTX, R5);  // Isolate.
+  // Set the tag.
+  __ LoadImmediate(R2, VMTag::kScriptTagId, kNoPP);
+  __ StoreToOffset(R2, CTX, Isolate::vm_tag_offset(), kNoPP);
+  // Clear top exit frame.
+  __ StoreToOffset(ZR, CTX, Isolate::top_exit_frame_info_offset(), kNoPP);

[siva, 2014/07/14 20:13:12]

Ditto comment about CTX here and in other target files.

[Cutch, 2014/07/14 21:32:08]

Acknowledged.

   __ ret();  // Jump to the exception handler code.
 }