commit 2f19bf4fd4ea7473429ee92f6ea6439ef7551bde
author Ivan Inozemtsev <iinozemtsev@google.com> Wed Apr 05 15:21:57 2023 +0000
committer Commit Queue <dart-scoped@luci-project-accounts.iam.gserviceaccount.com> Wed Apr 05 15:21:57 2023 +0000
tree 2f9581f896b85b2e20140bcd2120d614d6304642
parent 20354f87fdc8937c416de425b323005ccb124dd0

Revert "[dart2js] Throw in BlockExpression should not generate exit edge"

This reverts commit 6bdf3c042a473f6df5da7b05a1beb5e5eb249996.

Reason for revert: b/276976255

Original change's description:
> [dart2js] Throw in BlockExpression should not generate exit edge
>
> dart2js's CFG builder can't handle exit edges from expressions, so
> don't generate one for a throw nested in a BlockExpression.
>
> Bug: #51847
> Change-Id: I8afeb2785fc62c32ea07500ecb7a0b61fd4756b5
> Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/293162
> Commit-Queue: Stephen Adams <sra@google.com>
> Reviewed-by: Sigmund Cherem <sigmund@google.com>

Bug: #51847
Change-Id: I94172897dd272f9d8896faa06de9ed5f0d3a1b97
No-Presubmit: true
No-Tree-Checks: true
No-Try: true
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/293641
Auto-Submit: Ivan Inozemtsev <iinozemtsev@google.com>
Reviewed-by: Stephen Adams <sra@google.com>
Bot-Commit: Rubber Stamper <rubber-stamper@appspot.gserviceaccount.com>
Commit-Queue: Stephen Adams <sra@google.com>

pkg/compiler/lib/src/ssa/builder.dart

diff --git a/pkg/compiler/lib/src/ssa/builder.dart b/pkg/compiler/lib/src/ssa/builder.dart
index 2158ade..da8e9b1 100644
--- a/pkg/compiler/lib/src/ssa/builder.dart
+++ b/pkg/compiler/lib/src/ssa/builder.dart
@@ -268,9 +268,6 @@
   /// [isAborted].
   bool _isReachable = true;
 
-  /// Is the current statement or expression nested in a [ir.BlockExpression]?
-  bool _inBlockExpression = false;
-
   HLocalValue? lastAddedParameter;
 
   Map<Local, HInstruction> parameters = {};
@@ -1905,13 +1902,7 @@
   void visitExpressionStatement(ir.ExpressionStatement node) {
     if (!_isReachable) return;
     ir.Expression expression = node.expression;
-
-    // Handle a `throw` expression in statement-position, with control flow to
-    // the exit. (In expression position the throw does not create control-flow
-    // out of CFG region for the expression).
-    if (expression is ir.Throw &&
-        _inliningStack.isEmpty &&
-        !_inBlockExpression) {
+    if (expression is ir.Throw && _inliningStack.isEmpty) {
       _visitThrowExpression(expression.expression);
       _handleInTryStatement();
       final sourceInformation =
@@ -1975,9 +1966,7 @@
         return;
       }
     }
-    if (_isReachable) {
-      _emitReturn(value, sourceInformation);
-    }
+    _emitReturn(value, sourceInformation);
   }
 
   @override
@@ -3868,11 +3857,7 @@
     HInstruction initializedValue = pop();
     // TODO(sra): Apply inferred type information.
     _letBindings[variable] = initializedValue;
-    if (!_isReachable) {
-      stack.add(graph.addConstantUnreachable(closedWorld));
-    } else {
-      node.body.accept(this);
-    }
+    node.body.accept(this);
   }
 
   @override
@@ -3883,13 +3868,7 @@
     if (!_isReachable) {
       stack.add(graph.addConstantUnreachable(closedWorld));
     } else {
-      final previous = _inBlockExpression;
-      try {
-        _inBlockExpression = true;
-        node.value.accept(this);
-      } finally {
-        _inBlockExpression = previous;
-      }
+      node.value.accept(this);
     }
   }