Let NaN flow as double into HBranch

src/x64/lithium-x64.cc

Index: src/x64/lithium-x64.cc
diff --git a/src/x64/lithium-x64.cc b/src/x64/lithium-x64.cc
index f776bf339f5d595e63a9a2633a72f7927efd4e97..195d48b23bf5dd1f3f9ea1a8f385342f0d9d4fb2 100644
--- a/src/x64/lithium-x64.cc
+++ b/src/x64/lithium-x64.cc
@@ -1015,9 +1015,11 @@ LInstruction* LChunkBuilder::DoBranch(HBranch* instr) {
   LBranch* result = new(zone()) LBranch(UseRegister(value));
   // Tagged values that are not known smis or booleans require a
   // deoptimization environment.
+  ToBooleanStub::Types expected = instr->expected_input_types();
   Representation rep = value->representation();
   HType type = value->type();
-  if (rep.IsTagged() && !type.IsSmi() && !type.IsBoolean()) {
+  if (rep.IsTagged() && !type.IsSmi() && !type.IsBoolean() &&
+      expected != ToBooleanStub::all_types()) {

[Toon Verwaest, 2013/06/18 17:01:52]

Can you add a comment what expected == all_types means?
Also, can we make ia32/x64 and ARM agree on &&,! vs ||? 

     return AssignEnvironment(result);
   }
   return result;