Record ToBoolean's type information in Hydrogen's HBranch instruction, so we can use it in LCodeG...

src/hydrogen.cc

Index: src/hydrogen.cc
===================================================================
--- src/hydrogen.cc	(revision 8716)
+++ src/hydrogen.cc	(working copy)
@@ -2158,7 +2158,9 @@
   }
   HBasicBlock* empty_true = builder->graph()->CreateBasicBlock();
   HBasicBlock* empty_false = builder->graph()->CreateBasicBlock();
-  HBranch* test = new(zone()) HBranch(value, empty_true, empty_false);
+  unsigned test_id = condition()->test_id();
+  ToBooleanStub::Types expected(builder->oracle()->ToBooleanTypes(test_id));

[fschneider, 2011/07/25 11:55:19]

It would be nicer to just write

ToBooleanStub::Types expected = builder->oracle()->ToBooleanTypes(test_id);

[Sven Panne, 2011/07/25 14:06:32]

I think that using the combination of an empty constructor plus assignment
operator is actually worse than using the parameterized constructor alone,
because the former potentially wastes effort. In our concrete case, it probably
won't make a big difference, but in general the former is not a good idea IMHO.
(The user of a class shouldn't be required to know that the compiler hopefully
irons out any inefficiencies.)

+  HBranch* test = new(zone()) HBranch(value, empty_true, empty_false, expected);
   builder->current_block()->Finish(test);
 
   empty_true->Goto(if_true());
@@ -5504,9 +5506,11 @@
     // We need an extra block to maintain edge-split form.
     HBasicBlock* empty_block = graph()->CreateBasicBlock();
     HBasicBlock* eval_right = graph()->CreateBasicBlock();
+    unsigned test_id = expr->left()->test_id();
+    ToBooleanStub::Types expected(oracle()->ToBooleanTypes(test_id));
     HBranch* test = is_logical_and
-      ? new(zone()) HBranch(Top(), eval_right, empty_block)
-      : new(zone()) HBranch(Top(), empty_block, eval_right);
+      ? new(zone()) HBranch(Top(), eval_right, empty_block, expected)
+      : new(zone()) HBranch(Top(), empty_block, eval_right, expected);
     current_block()->Finish(test);
 
     set_current_block(eval_right);