A64: Temporary fix for predictable code size in LCodeGen::DoStackCheck.

src/a64/lithium-codegen-a64.cc

Index: src/a64/lithium-codegen-a64.cc
diff --git a/src/a64/lithium-codegen-a64.cc b/src/a64/lithium-codegen-a64.cc
index 3955cc26e91c3beb4d6768b0b3b8eb8b0926eb54..56b29ceb09e0d5d9622517e584476bdc2a57e702 100644
--- a/src/a64/lithium-codegen-a64.cc
+++ b/src/a64/lithium-codegen-a64.cc
@@ -4575,9 +4575,13 @@ void LCodeGen::DoStackCheck(LStackCheck* instr) {
     __ CompareRoot(masm()->StackPointer(), Heap::kStackLimitRootIndex);
     __ B(hs, &done);
 
-    // TODO(jbramley): This PredictableCodeSizeScope fails sometimes. Sometimes
-    // the code tries to generate 3 instructions, and sometimes it tries to
-    // generate 2. Work out why, and fix it.
+    // TODO(bafsa): Make sure that the EnsureSpaceForLazyDeopt inside
+    // CallCodeGeneric will not insert any nop while calling the stub by
+    // inserting them now. The EnsureSpaceForLazyDeopt in CallCodeGeneric
+    // will go away at some point during the rebase (r18642) so this will become
+    // unecessary and should be removed at this point.
+    EnsureSpaceForLazyDeopt();
+
     PredictableCodeSizeScope predictable(masm_,
                                          Assembler::kCallSizeWithRelocation);
     StackCheckStub stub;