[coverage] Block coverage with support for IfStatements

src/compiler/bytecode-graph-builder.cc

 // Copyright 2015 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.
 
 #include "src/compiler/bytecode-graph-builder.h"
 
 #include "src/ast/ast.h"
 #include "src/ast/scopes.h"
 #include "src/compiler/access-builder.h"
 #include "src/compiler/compiler-source-position-table.h"
@@ skipping 2199 matching lines @@
   Node* call = NewNode(javascript()->Debugger());
   environment()->RecordAfterState(call, Environment::kAttachFrameState);
 }
 
 // We cannot create a graph from the debugger copy of the bytecode array.
 #define DEBUG_BREAK(Name, ...) \
   void BytecodeGraphBuilder::Visit##Name() { UNREACHABLE(); }
 DEBUG_BREAK_BYTECODE_LIST(DEBUG_BREAK);
 #undef DEBUG_BREAK
 
+void BytecodeGraphBuilder::VisitIncBlockCounter() {
+  DCHECK(FLAG_block_coverage);
+
+  PrepareEagerCheckpoint();

[rmcilroy, 2017/05/18 14:17:59]

I don't think you would need a Checkpoint for this bytecode since it can't call
into JS - just add the runtime call into the whitelist in
Linkage::NeedsFrameStateInput.

[jgruber, 2017/05/22 09:43:32]

Done.

+
+  Node* slot = jsgraph()->Constant(bytecode_iterator().GetImmediateOperand(0));
+  Node* vector = jsgraph()->Constant(feedback_vector());
+
+  const Operator* op = javascript()->CallRuntime(Runtime::kIncBlockCounter);
+
+  Node* node = NewNode(op, vector, slot);
+  environment()->RecordAfterState(node, Environment::kAttachFrameState);
+}
+
 void BytecodeGraphBuilder::VisitForInPrepare() {
   PrepareEagerCheckpoint();
   Node* receiver =
       environment()->LookupRegister(bytecode_iterator().GetRegisterOperand(0));
   Node* prepare = NewNode(javascript()->ForInPrepare(), receiver);
   environment()->BindRegistersToProjections(
       bytecode_iterator().GetRegisterOperand(1), prepare,
       Environment::kAttachFrameState);
 }
 
@@ skipping 596 matching lines @@
         it->source_position().ScriptOffset(), start_position_.InliningId()));
     it->Advance();
   } else {
     DCHECK_GT(it->code_offset(), offset);
   }
 }
 
 }  // namespace compiler
 }  // namespace internal
 }  // namespace v8