Add flag to control number of stack frames collected by profiler

runtime/vm/profiler_test.cc

Index: runtime/vm/profiler_test.cc
diff --git a/runtime/vm/profiler_test.cc b/runtime/vm/profiler_test.cc
index b0c580e70eec33eef1e0d3c2df6cd821027966be..ffa9ab322306c67718322481349c8802a71c9c6d 100644
--- a/runtime/vm/profiler_test.cc
+++ b/runtime/vm/profiler_test.cc
@@ -17,13 +17,15 @@ class ProfileSampleBufferTestHelper {
   static intptr_t IterateCount(const Isolate* isolate,
                                const SampleBuffer& sample_buffer) {
     intptr_t c = 0;
+    Sample* sample = Sample::Allocate();
     for (intptr_t i = 0; i < sample_buffer.capacity(); i++) {
-      Sample sample = sample_buffer.GetSample(i);
-      if (sample.isolate != isolate) {
+      sample_buffer.CopySample(i, sample);
+      if (sample->isolate() != isolate) {
         continue;
       }
       c++;
     }
+    free(sample);
     return c;
   }
 
@@ -31,13 +33,15 @@ class ProfileSampleBufferTestHelper {
   static intptr_t IterateSumPC(const Isolate* isolate,
                                const SampleBuffer& sample_buffer) {
     intptr_t c = 0;
+    Sample* sample = Sample::Allocate();
     for (intptr_t i = 0; i < sample_buffer.capacity(); i++) {
-      Sample sample = sample_buffer.GetSample(i);
-      if (sample.isolate != isolate) {
+      sample_buffer.CopySample(i, sample);
+      if (sample->isolate() != isolate) {
         continue;
       }
-      c += sample.pcs[0];
+      c += sample->At(0);
     }
+    free(sample);
     return c;
   }
 };
@@ -49,20 +53,20 @@ TEST_CASE(ProfilerSampleBufferWrapTest) {
   EXPECT_EQ(0, ProfileSampleBufferTestHelper::IterateSumPC(i, *sample_buffer));
   Sample* s;
   s = sample_buffer->ReserveSample();
-  s->isolate = i;
-  s->pcs[0] = 2;
+  s->Init(Sample::kIsolateSample, i, 0, 0);
+  s->SetAt(0, 2);
   EXPECT_EQ(2, ProfileSampleBufferTestHelper::IterateSumPC(i, *sample_buffer));
   s = sample_buffer->ReserveSample();
-  s->isolate = i;
-  s->pcs[0] = 4;
+  s->Init(Sample::kIsolateSample, i, 0, 0);
+  s->SetAt(0, 4);
   EXPECT_EQ(6, ProfileSampleBufferTestHelper::IterateSumPC(i, *sample_buffer));
   s = sample_buffer->ReserveSample();
-  s->isolate = i;
-  s->pcs[0] = 6;
+  s->Init(Sample::kIsolateSample, i, 0, 0);
+  s->SetAt(0, 6);
   EXPECT_EQ(12, ProfileSampleBufferTestHelper::IterateSumPC(i, *sample_buffer));
   s = sample_buffer->ReserveSample();
-  s->isolate = i;
-  s->pcs[0] = 8;
+  s->Init(Sample::kIsolateSample, i, 0, 0);
+  s->SetAt(0, 8);
   EXPECT_EQ(18, ProfileSampleBufferTestHelper::IterateSumPC(i, *sample_buffer));
   delete sample_buffer;
 }
@@ -74,16 +78,16 @@ TEST_CASE(ProfilerSampleBufferIterateTest) {
   EXPECT_EQ(0, ProfileSampleBufferTestHelper::IterateCount(i, *sample_buffer));
   Sample* s;
   s = sample_buffer->ReserveSample();
-  s->isolate = i;
+  s->Init(Sample::kIsolateSample, i, 0, 0);
   EXPECT_EQ(1, ProfileSampleBufferTestHelper::IterateCount(i, *sample_buffer));
   s = sample_buffer->ReserveSample();
-  s->isolate = i;
+  s->Init(Sample::kIsolateSample, i, 0, 0);
   EXPECT_EQ(2, ProfileSampleBufferTestHelper::IterateCount(i, *sample_buffer));
   s = sample_buffer->ReserveSample();
-  s->isolate = i;
+  s->Init(Sample::kIsolateSample, i, 0, 0);
   EXPECT_EQ(3, ProfileSampleBufferTestHelper::IterateCount(i, *sample_buffer));
   s = sample_buffer->ReserveSample();
-  s->isolate = i;
+  s->Init(Sample::kIsolateSample, i, 0, 0);
   EXPECT_EQ(3, ProfileSampleBufferTestHelper::IterateCount(i, *sample_buffer));
   delete sample_buffer;
 }