Test tracing of string allocations

runtime/vm/intrinsifier_arm64.cc

 // Copyright (c) 2014, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 #include "vm/globals.h"  // Needed here to get TARGET_ARCH_ARM64.
 #if defined(TARGET_ARCH_ARM64)
 
 #include "vm/intrinsifier.h"
 
 #include "vm/assembler.h"
@@ skipping 1825 matching lines @@
 
 // Allocates one-byte string of length 'end - start'. The content is not
 // initialized.
 // 'length-reg' (R2) contains tagged length.
 // Returns new string as tagged pointer in R0.
 static void TryAllocateOnebyteString(Assembler* assembler,
                                      Label* ok,
                                      Label* failure) {
   const Register length_reg = R2;
   Label fail;
-
+  __ MaybeTraceAllocation(kOneByteStringCid, R0, kNoPP, failure);
   __ mov(R6, length_reg);  // Save the length register.
   // TODO(koda): Protect against negative length and overflow here.
   __ SmiUntag(length_reg);
   const intptr_t fixed_size = sizeof(RawString) + kObjectAlignment - 1;
   __ AddImmediate(length_reg, length_reg, fixed_size, kNoPP);
   __ andi(length_reg, length_reg, Immediate(~(kObjectAlignment - 1)));
 
   Isolate* isolate = Isolate::Current();
   Heap* heap = isolate->heap();
   const intptr_t cid = kOneByteStringCid;
@@ skipping 281 matching lines @@
   Isolate* isolate = Isolate::Current();
   __ LoadImmediate(R1, reinterpret_cast<uword>(isolate), kNoPP);
   // Set return value to Isolate::current_tag_.
   __ ldr(R0, Address(R1, Isolate::current_tag_offset()));
   __ ret();
 }
 
 }  // namespace dart
 
 #endif  // defined TARGET_ARCH_ARM64