Implement try/catch without finally, and without type checks.

frog/leg/ssa/bailout.dart

 // Copyright (c) 2012, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 class BailoutInfo {
   int instructionId;
   int bailoutId;
   BailoutInfo(this.instructionId, this.bailoutId);
 }
 
@@ skipping 175 matching lines @@
         environment.add(phi.inputs[i]);
       }
     }
 
     if (!branch.isDoWhile()) {
       assert(block.successors[0] == block.dominatedBlocks[0]);
       visitBasicBlock(block.successors[0]);
     }
   }
 
+  void visitTry(HTry node) {
+    List<HBasicBlock> successors = node.block.successors;
+    for (int i = 0; i < successors.length; i++) {
+      visitBasicBlock(successors[i]);

[ngeoffray, 2012/02/08 07:56:03]

I know this is wrong. I plan on adding test cases for bailouts to make sure we
visit the right order and the liveness of variables is computed correctly.

[ngeoffray, 2012/02/08 09:52:23]

After discussions, decided to not do any speculative optimizations on try/catch
for now.

+    }
+  }
+
   // Deal with all kinds of control flow instructions. In case we add
   // a new one, we will hit an internal error.
   void visitExit(HExit exit) {}
   void visitReturn(HReturn instruction) {}
   void visitThrow(HThrow instruction) {}
 
   void visitControlFlow(HControlFlow instruction) {
     compiler.internalError('Control flow instructions already dealt with.',
                            instruction: instruction);
   }
@@ skipping 113 matching lines @@
   void visitLoopBranch(HLoopBranch branch) {
     HBasicBlock branchBlock = branch.block;
     if (!branch.isDoWhile()) {
       // Not a do while loop. We visit the body of the loop.
       visitBasicBlock(branchBlock.dominatedBlocks[0]);
     }
     blocks.removeLast();
     visitBasicBlock(branchBlock.successors[1]);
   }
 
+  void visitTry(HTry node) {
+    List<HBasicBlock> successors = node.block.successors;
+    for (int i = 0; i < successors.length; i++) {
+      visitBasicBlock(successors[i]);
+    }

[ngeoffray, 2012/02/08 07:56:03]

ditto.

+  }
+
   // Deal with all kinds of control flow instructions. In case we add
   // a new one, we will hit an internal error.
   void visitExit(HExit exit) {}
   void visitReturn(HReturn instruction) {}
   void visitThrow(HThrow instruction) {}
 
   void visitControlFlow(HControlFlow instruction) {
     compiler.internalError('Control flow instructions already dealt with.',
                            instruction: instruction);
   }
 
   visitBailoutTarget(HBailoutTarget target) {
     blocks.forEach((HBasicBlock block) {
       block.bailouts.add(target);
     });
   }
 }