Fix crash in arm conditional expression code generation.

src/arm/codegen-arm.cc

Index: src/arm/codegen-arm.cc
===================================================================
--- src/arm/codegen-arm.cc	(revision 2383)
+++ src/arm/codegen-arm.cc	(working copy)
@@ -2424,13 +2424,23 @@
   JumpTarget exit;
   LoadConditionAndSpill(node->condition(), NOT_INSIDE_TYPEOF,
                         &then, &else_, true);
-  Branch(false, &else_);
-  then.Bind();
-  LoadAndSpill(node->then_expression(), typeof_state());
-  exit.Jump();
-  else_.Bind();
-  LoadAndSpill(node->else_expression(), typeof_state());
-  exit.Bind();
+  if (frame_ != NULL) {
+    Branch(false, &else_);
+  }
+  if (frame_ != NULL || then.is_linked()) {
+    then.Bind();
+    LoadAndSpill(node->then_expression(), typeof_state());
+  }
+  if (frame_ != NULL) {

[Kevin Millikin (Chromium), 2009/07/09 01:20:31]

You only need to jump around the else part if you are going to emit it.  You
could write:

if (else_.is_linked()) {
  JumpTarget exit;
  if (has_valid_frame()) exit.Jump();
  LoadAndSpill(node->else_expression(), typeof_state());
  if (exit.is_linked()) exit.Bind();
}

[Mads Ager (chromium), 2009/07/09 04:11:08]

Done.  I left the binding of the else_ JumpTarget in there though.  :-)

+    exit.Jump();
+  }
+  if (else_.is_linked()) {
+    else_.Bind();
+    LoadAndSpill(node->else_expression(), typeof_state());
+  }
+  if (exit.is_linked()) {
+    exit.Bind();
+  }
   ASSERT(frame_->height() == original_height + 1);
 }