Fix bug in optimized compiler's switch-statement.

In the case where the default-clause occurs as the first clause,
the case-blocks were not wired up correctly.

BUG=v8:1394
TEST=mjsunit/compiler/regress-1394.js
Review URL: http://codereview.chromium.org/7037023

git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@7927 ce2b1a6d-e550-0410-aec6-3dcde31c8c00

diff --git a/src/hydrogen.cc b/src/hydrogen.cc
index 17d0131881b879fc2d33a8d24100350ccf5c4d9f..35981ae6c63958b61d7e2af4be099ce8e089f155 100644 (file)
--- a/src/hydrogen.cc
+++ b/src/hydrogen.cc
@@ -2535,9 +2535,11 @@ void HGraphBuilder::VisitSwitchStatement(SwitchStatement* stmt) {
       // Identify the block where normal (non-fall-through) control flow
       // goes to.
       HBasicBlock* normal_block = NULL;
-      if (clause->is_default() && last_block != NULL) {
-        normal_block = last_block;
-        last_block = NULL;  // Cleared to indicate we've handled it.
+      if (clause->is_default()) {
+        if (last_block != NULL) {
+          normal_block = last_block;
+          last_block = NULL;  // Cleared to indicate we've handled it.
+        }
       } else if (!curr_test_block->end()->IsDeoptimize()) {
         normal_block = curr_test_block->end()->FirstSuccessor();
         curr_test_block = curr_test_block->end()->SecondSuccessor();

diff --git a/test/mjsunit/compiler/regress-1394.js b/test/mjsunit/compiler/regress-1394.js
new file mode 100644 (file)
index 0000000..b1ce192
--- /dev/null
+++ b/test/mjsunit/compiler/regress-1394.js
@@ -0,0 +1,59 @@
+// Copyright 2011 the V8 project authors. All rights reserved.
+// Redistribution and use in source and binary forms, with or without
+// modification, are permitted provided that the following conditions are
+// met:
+//
+//     * Redistributions of source code must retain the above copyright
+//       notice, this list of conditions and the following disclaimer.
+//     * Redistributions in binary form must reproduce the above
+//       copyright notice, this list of conditions and the following
+//       disclaimer in the documentation and/or other materials provided
+//       with the distribution.
+//     * Neither the name of Google Inc. nor the names of its
+//       contributors may be used to endorse or promote products derived
+//       from this software without specific prior written permission.
+//
+// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+// Flags: --allow-natives-syntax
+
+function f(x) {
+  var ret = -1;
+  switch(x){
+    default:
+    case 0:
+      ret = 0;
+      break;
+    case 1:
+      ret = 1;
+      break;
+    case 2:
+      ret = 2;
+      break;
+    case 3:
+      ret = 3;
+      break;
+    case 4:
+      ret = 4;
+      break;
+  }
+  return ret;
+};
+
+for (var i = 0; i < 3; i++) assertEquals(i, f(i));
+
+%OptimizeFunctionOnNextCall(f);
+
+assertEquals(0, f(0));
+assertEquals(1, f(1));
+