[coverage] Block coverage with support for IfStatements

src/debug/debug-interface.h

 // Copyright 2016 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef V8_DEBUG_DEBUG_INTERFACE_H_
 #define V8_DEBUG_DEBUG_INTERFACE_H_
 
 #include <functional>
 
 #include "include/v8-debug.h"
 #include "include/v8-util.h"
 #include "include/v8.h"
 
 #include "src/debug/interface-types.h"
 #include "src/globals.h"
 
 namespace v8 {
 
 namespace internal {
+struct CoverageBlock;
 struct CoverageFunction;
 struct CoverageScript;
 class Coverage;
 class Script;
 }
 
 namespace debug {
 
 void SetContextId(Local<Context> context, int id);
 int GetContextId(Local<Context> context);
@@ skipping 208 matching lines @@
     // Only return a yes/no result. Optimization and GC are not affected.
     // Collecting best effort coverage does not reset counters.
     kBestEffort,
     // Disable optimization and prevent feedback vectors from being garbage
     // collected in order to preserve precise invocation counts. Collecting
     // precise count coverage resets counters to get incremental updates.
     kPreciseCount,
     // We are only interested in a yes/no result for the function. Optimization
     // and GC can be allowed once a function has been invoked. Collecting
     // precise binary coverage resets counters for incremental updates.
-    kPreciseBinary
+    kPreciseBinary,
+    // Similar to the precise coverage modes but provides coverage at a
+    // lower granularity. Design doc: goo.gl/lA2swZ.
+    kBlockCount,
   };
 
-  class ScriptData;  // Forward declaration.
+  // Forward declarations.
+  class ScriptData;
+  class FunctionData;
+
+  class V8_EXPORT_PRIVATE BlockData {
+   public:
+    int StartOffset() const;
+    int EndOffset() const;
+    uint32_t Count() const;
+
+   private:
+    explicit BlockData(i::CoverageBlock* block) : block_(block) {}
+    i::CoverageBlock* block_;
+
+    friend class v8::debug::Coverage::FunctionData;
+  };
 
   class V8_EXPORT_PRIVATE FunctionData {
    public:
     int StartOffset() const;
     int EndOffset() const;
     uint32_t Count() const;
     MaybeLocal<String> Name() const;
+    size_t BlockCount() const;
+    BlockData GetBlockData(size_t i) const;
 
    private:
     explicit FunctionData(i::CoverageFunction* function)
         : function_(function) {}
     i::CoverageFunction* function_;
 
     friend class v8::debug::Coverage::ScriptData;
   };
 
   class V8_EXPORT_PRIVATE ScriptData {
@@ skipping 21 matching lines @@
   ~Coverage();
 
  private:
   explicit Coverage(i::Coverage* coverage) : coverage_(coverage) {}
   i::Coverage* coverage_;
 };
 }  // namespace debug
 }  // namespace v8
 
 #endif  // V8_DEBUG_DEBUG_INTERFACE_H_