Initial UserTag and dart:profiler library

runtime/vm/profiler.cc

Index: runtime/vm/profiler.cc
diff --git a/runtime/vm/profiler.cc b/runtime/vm/profiler.cc
index 24d3da973f44574fe46971f0885cf3350147fb1e..acf90fc476e5b1c3f8db99edac71fe8032a3eafc 100644
--- a/runtime/vm/profiler.cc
+++ b/runtime/vm/profiler.cc
@@ -564,9 +564,17 @@ class CodeRegion : public ZoneAllocated {
       PrintOverwrittenCode(&obj);
     } else if (kind() == kTagCode) {
       if (name() == NULL) {
-        const char* tag_name = start() == 0 ? "root" : VMTag::TagName(start());
-        ASSERT(tag_name != NULL);
-        SetName(tag_name);
+        if (VMTag::IsVMTag(start())) {
+          const char* tag_name = VMTag::TagName(start());
+          ASSERT(tag_name != NULL);
+          SetName(tag_name);
+        } else if (start() != 0) {
+          const char* tag_name = UserTagHelper::TagName(start());
+          ASSERT(tag_name != NULL);
+          SetName(tag_name);
+        } else {
+          SetName("root");
+        }
       }
       PrintTagCode(&obj);
     } else {
@@ -927,6 +935,8 @@ class CodeRegionTableBuilder : public SampleVisitor {
     }
     // Make sure VM tag is created.
     CreateTag(sample->vm_tag());
+    // Make sure user tag is created.
+    CreateUserTag(sample->user_tag());
     // Exclusive tick for bottom frame.
     Tick(sample->At(0), true, timestamp);
     // Inclusive tick for all frames.
@@ -962,6 +972,21 @@ class CodeRegionTableBuilder : public SampleVisitor {
     region->set_creation_serial(visited());
   }
 
+  void CreateUserTag(uword tag) {
+    intptr_t index = tag_code_table_->FindIndex(tag);
+    if (index >= 0) {
+      // Already created.
+      return;
+    }
+    CodeRegion* region = new CodeRegion(CodeRegion::kTagCode,
+                                        tag,
+                                        tag + 1,
+                                        0);
+    index = tag_code_table_->InsertCodeRegion(region);
+    ASSERT(index >= 0);
+    region->set_creation_serial(visited());
+  }
+
   void Tick(uword pc, bool exclusive, int64_t timestamp) {
     CodeRegionTable::TickResult r;
     intptr_t serial = exclusive ? -1 : visited();
@@ -1101,8 +1126,14 @@ class CodeRegionExclusiveTrieBuilder : public SampleVisitor {
     root_->Tick();
     CodeRegionTrieNode* current = root_;
     if (use_tags()) {
-      intptr_t tag_index = FindTagIndex(sample->vm_tag());
-      current = current->GetChild(tag_index);
+      intptr_t user_tag_index = FindTagIndex(sample->user_tag());
+      if (user_tag_index >= 0) {
+        current = current->GetChild(user_tag_index);
+        // Give the tag a tick.
+        current->Tick();
+      }
+      intptr_t vm_tag_index = FindTagIndex(sample->vm_tag());
+      current = current->GetChild(vm_tag_index);
       // Give the tag a tick.
       current->Tick();
     }
@@ -1132,6 +1163,9 @@ class CodeRegionExclusiveTrieBuilder : public SampleVisitor {
  private:
   intptr_t FindTagIndex(uword tag) const {
     intptr_t index = tag_code_table_->FindIndex(tag);
+    if (index <= 0) {
+      return -1;
+    }
     ASSERT(index >= 0);
     ASSERT((tag_code_table_->At(index))->contains(tag));
     return tag_code_table_offset_ + index;
@@ -1431,13 +1465,15 @@ class ProfilerSampleStackWalker : public ValueObject {
     ASSERT(sample_ != NULL);
   }
 
-  int walk(Heap* heap, uword vm_tag) {
+  int walk(Heap* heap, uword vm_tag, uword user_tag) {
     const intptr_t kMaxStep = 0x1000;  // 4K.
     const bool kWalkStack = true;  // Walk the stack.
     // Always store the exclusive PC.
     sample_->SetAt(0, original_pc_);
     // Always store the vm tag.
     sample_->set_vm_tag(vm_tag);
+    // Always store the user tag.
+    sample_->set_user_tag(user_tag);
     if (!kWalkStack) {
       // Not walking the stack, only took exclusive sample.
       return 1;
@@ -1466,6 +1502,9 @@ class ProfilerSampleStackWalker : public ValueObject {
         VerifyCodeAddress(heap, i, reinterpret_cast<uword>(pc));
       }
       sample_->SetAt(i, reinterpret_cast<uword>(pc));
+      if (fp == NULL) {
+        return i + 1;
+      }
       if (!ValidFramePointer(fp)) {
         return i + 1;
       }
@@ -1473,9 +1512,18 @@ class ProfilerSampleStackWalker : public ValueObject {
       previous_fp = fp;
       fp = CallerFP(fp);
       intptr_t step = fp - previous_fp;
-      if ((step >= kMaxStep) || (fp <= previous_fp) || !ValidFramePointer(fp)) {
+      if (fp == NULL) {
+        return i + 1;
+      }
+      if ((step >= kMaxStep)) {
         // Frame pointer step is too large.
+        return i + 1;
+      }
+      if ((fp <= previous_fp)) {
         // Frame pointer did not move to a higher address.
+        return i + 1;
+      }
+      if (!ValidFramePointer(fp)) {
         // Frame pointer is outside of isolate stack bounds.
         return i + 1;
       }
@@ -1559,7 +1607,7 @@ void Profiler::RecordSampleInterruptCallback(
   }
   ProfilerSampleStackWalker stackWalker(sample, stack_lower, stack_upper,
                                         state.pc, state.fp, state.sp);
-  stackWalker.walk(isolate->heap(), isolate->vm_tag());
+  stackWalker.walk(isolate->heap(), isolate->vm_tag(), isolate->user_tag());
 }
 
 }  // namespace dart