Streamline throwing in the C entry stub.

src/x64/code-stubs-x64.cc

Index: src/x64/code-stubs-x64.cc
diff --git a/src/x64/code-stubs-x64.cc b/src/x64/code-stubs-x64.cc
index 9feef086e8e1acb7b59375bb0956a39ff423077d..ff36264193ff96bd5be472d7788c60096c4c89ad 100644
--- a/src/x64/code-stubs-x64.cc
+++ b/src/x64/code-stubs-x64.cc
@@ -3054,7 +3054,7 @@ void RegExpExecStub::Generate(MacroAssembler* masm) {
   __ Throw(rax);
 
   __ bind(&termination_exception);
-  __ ThrowUncatchable(TERMINATION, rax);
+  __ ThrowUncatchable(rax);
 
   // External string.  Short external strings have already been ruled out.
   // rdi: subject string (expected to be external)
@@ -3775,12 +3775,6 @@ void CEntryStub::GenerateAheadOfTime() {
 }
 
 
-void CEntryStub::GenerateThrowTOS(MacroAssembler* masm) {
-  // Throw exception in eax.
-  __ Throw(rax);
-}
-
-
 void CEntryStub::GenerateCore(MacroAssembler* masm,
                               Label* throw_normal_exception,
                               Label* throw_termination_exception,
@@ -3921,12 +3915,6 @@ void CEntryStub::GenerateCore(MacroAssembler* masm,
 }
 
 
-void CEntryStub::GenerateThrowUncatchable(MacroAssembler* masm,
-                                          UncatchableExceptionType type) {
-  __ ThrowUncatchable(type, rax);
-}
-
-
 void CEntryStub::Generate(MacroAssembler* masm) {
   // rax: number of arguments including receiver
   // rbx: pointer to C function  (C callee-saved)
@@ -3990,13 +3978,25 @@ void CEntryStub::Generate(MacroAssembler* masm) {
                true);
 
   __ bind(&throw_out_of_memory_exception);
-  GenerateThrowUncatchable(masm, OUT_OF_MEMORY);
+  // Set external caught exception to false.
+  Isolate* isolate = masm->isolate();
+  ExternalReference external_caught(Isolate::kExternalCaughtExceptionAddress,
+                                    isolate);
+  __ Set(rax, static_cast<int64_t>(false));
+  __ Store(external_caught, rax);
+
+  // Set pending exception and rax to out of memory exception.
+  ExternalReference pending_exception(Isolate::kPendingExceptionAddress,
+                                      isolate);
+  __ movq(rax, Failure::OutOfMemoryException(), RelocInfo::NONE);
+  __ Store(pending_exception, rax);
+  // Fall through to the next label.
 
   __ bind(&throw_termination_exception);
-  GenerateThrowUncatchable(masm, TERMINATION);
+  __ ThrowUncatchable(rax);
 
   __ bind(&throw_normal_exception);
-  GenerateThrowTOS(masm);
+  __ Throw(rax);
 }