A64: Implement LOsrEntry and LUnknownOSRValue

src/a64/full-codegen-a64.cc

 // Copyright 2013 the V8 project authors. All rights reserved.
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
 //
 //     * Redistributions of source code must retain the above copyright
 //       notice, this list of conditions and the following disclaimer.
 //     * Redistributions in binary form must reproduce the above
 //       copyright notice, this list of conditions and the following
 //       disclaimer in the documentation and/or other materials provided
@@ skipping 348 matching lines @@
     ASSERT(back_edge_target->is_bound());
     int distance = masm_->SizeOfCodeGeneratedSince(back_edge_target);
     weight = Min(kMaxBackEdgeWeight,
                  Max(1, distance / kCodeSizeMultiplier));
   }
   EmitProfilingCounterDecrement(weight);
   __ B(pl, &ok);
   InterruptStub stub;
   __ CallStub(&stub);
 
-  // TODO(all): Implement OSR/Crankshaft code.
+  // Record a mapping of this PC offset to the OSR id.  This is used to find
+  // the AST id from the unoptimized code in order to use it as a key into
+  // the deoptimization input data found in the optimized code.
+  RecordBackEdge(stmt->OsrEntryId());
 
   EmitProfilingCounterReset();
 
   __ Bind(&ok);
   PrepareForBailoutForId(stmt->EntryId(), NO_REGISTERS);
-
-  // TODO(all): Implement OSR/Crankshaft code.
-  ASM_UNIMPLEMENTED(
-      "FullCodeGenerator::EmitBackEdgeBookkeeping "
-      "Implement OSR/Crankshaft code.");
+  // Record a mapping of the OSR id to this PC.  This is used if the OSR
+  // entry becomes the target of a bailout.  We don't expect it to be, but
+  // we want it to work if it is.
+  PrepareForBailoutForId(stmt->OsrEntryId(), NO_REGISTERS);
 }
 
 
 void FullCodeGenerator::EmitReturnSequence() {
   Comment cmnt(masm_, "[ Return sequence");
 
   if (return_label_.is_bound()) {
     __ B(&return_label_);
 
   } else {
@@ skipping 4603 matching lines @@
   return previous_;
 }
 
 
 #undef __
 
 
 } }  // namespace v8::internal
 
 #endif  // V8_TARGET_ARCH_A64