[coverage] Add continuation counters for catch and finally blocks

These counters handle cases in which the catch/finally block contains a jump
statement.

Bug: v8:6000
Change-Id: Ic83f11ee431edabe61f129c9abc3adc12a79c338
Reviewed-on: https://chromium-review.googlesource.com/586595Reviewed-by: Ross McIlroy <rmcilroy@chromium.org>
Reviewed-by: Georg Neis <neis@chromium.org>
Commit-Queue: Jakob Gruber <jgruber@chromium.org>
Cr-Commit-Position: refs/heads/master@{#46945}

src/ast/ast-source-ranges.h

@@ -190,8 +190,14 @@ class TryCatchStatementSourceRanges final : public AstNodeSourceRanges {
       : catch_range_(catch_range) {}
 
   SourceRange GetRange(SourceRangeKind kind) {
-    DCHECK(kind == SourceRangeKind::kCatch);
-    return catch_range_;
+    switch (kind) {
+      case SourceRangeKind::kCatch:
+        return catch_range_;
+      case SourceRangeKind::kContinuation:
+        return SourceRange::ContinuationOf(catch_range_);
+      default:
+        UNREACHABLE();
+    }
   }
 
  private:
@@ -204,8 +210,14 @@ class TryFinallyStatementSourceRanges final : public AstNodeSourceRanges {
       : finally_range_(finally_range) {}
 
   SourceRange GetRange(SourceRangeKind kind) {
-    DCHECK(kind == SourceRangeKind::kFinally);
-    return finally_range_;
+    switch (kind) {
+      case SourceRangeKind::kFinally:
+        return finally_range_;
+      case SourceRangeKind::kContinuation:
+        return SourceRange::ContinuationOf(finally_range_);
+      default:
+        UNREACHABLE();
+    }
   }
 
  private:

src/interpreter/bytecode-generator.cc

@@ -1572,6 +1572,8 @@ void BytecodeGenerator::VisitTryCatchStatement(TryCatchStatement* stmt) {
   BuildIncrementBlockCoverageCounterIfEnabled(stmt, SourceRangeKind::kCatch);
   VisitInScope(stmt->catch_block(), stmt->scope());
   try_control_builder.EndCatch();
+  BuildIncrementBlockCoverageCounterIfEnabled(stmt,
+                                              SourceRangeKind::kContinuation);
 }
 
 void BytecodeGenerator::VisitTryFinallyStatement(TryFinallyStatement* stmt) {
@@ -1637,6 +1639,8 @@ void BytecodeGenerator::VisitTryFinallyStatement(TryFinallyStatement* stmt) {
 
   // Dynamic dispatch after the finally-block.
   commands.ApplyDeferredCommands();
+  BuildIncrementBlockCoverageCounterIfEnabled(stmt,
+                                              SourceRangeKind::kContinuation);
 }
 
 void BytecodeGenerator::VisitDebuggerStatement(DebuggerStatement* stmt) {

test/mjsunit/code-coverage-block.js

@@ -355,10 +355,31 @@ TestCoverage(
  {"start":219,"end":232,"count":0},
  {"start":264,"end":274,"count":0},
  {"start":369,"end":380,"count":0},
- {"start":403,"end":414,"count":0},  // TODO(jgruber): Include `catch` in range.
+ {"start":390,"end":414,"count":0},  // TODO(jgruber): Include `catch` in range.
  {"start":513,"end":564,"count":0}]
 );
 
+TestCoverage("try/catch/finally statements with early return",
+`
+!function() {                             // 0000
+  try { throw 42; } catch (e) { return; } // 0050
+  nop();                                  // 0100
+}();                                      // 0150
+!function() {                             // 0200
+  try { throw 42; } catch (e) {}          // 0250
+  finally { return; }                     // 0300
+  nop();                                  // 0350
+}();                                      // 0400
+`,
+[{"start":0,"end":449,"count":1},
+ {"start":1,"end":151,"count":1},
+ {"start":67,"end":80,"count":0},
+ {"start":89,"end":151,"count":0},
+ {"start":201,"end":401,"count":1},
+ {"start":267,"end":280,"count":0},
+ {"start":319,"end":401,"count":0}]
+);
+
 TestCoverage(
 "early return in blocks",
 `
@@ -568,9 +589,9 @@ it.next(); it.return();                   // 0450
 `,
 [{"start":0,"end":449,"count":1},
  {"start":11,"end":351,"count":3},
- {"start":112,"end":253,"count":0},
+ {"start":112,"end":262,"count":0},
  {"start":262,"end":272,"count":1},
- {"start":310,"end":351,"count":0}]  // TODO(jgruber): Missing continuation.
+ {"start":272,"end":351,"count":0}]
 );
 
 TestCoverage("yield expressions (.throw and try/catch/finally)",
@@ -588,9 +609,8 @@ it.next(); it.throw(42);                  // 0550
 [{"start":0,"end":449,"count":1},
  {"start":11,"end":351,"count":3},
  {"start":112,"end":164,"count":0},
- {"start":164,"end":253,"count":1},
- {"start":262,"end":272,"count":1},
- {"start":310,"end":351,"count":0}]  // TODO(jgruber): Missing continuation.
+ {"start":164,"end":310,"count":1},
+ {"start":310,"end":351,"count":0}]
 );
 
 TestCoverage(