From f85ae576fe7e47e1aa8c0170681b4a6a635789a6 Mon Sep 17 00:00:00 2001
From: "Nicolas B. Pierron" <nicolas.b.pierron@mozilla.com>
Date: Fri, 28 Sep 2012 15:56:29 -0700
Subject: [PATCH] Bug 794286 - ReconstructPcStack, Keep hidden stack depth only
 when following gotos. r=luke

---
 js/src/jit-test/tests/basic/bug794286.js | 5 +++++
 js/src/jsopcode.cpp                      | 6 +++++-
 2 files changed, 10 insertions(+), 1 deletion(-)
 create mode 100644 js/src/jit-test/tests/basic/bug794286.js

diff --git a/js/src/jit-test/tests/basic/bug794286.js b/js/src/jit-test/tests/basic/bug794286.js
new file mode 100644
index 00000000000..6cba63ec4fd
--- /dev/null
+++ b/js/src/jit-test/tests/basic/bug794286.js
@@ -0,0 +1,5 @@
+for (var i = 0; i < 1; i++) {
+    let y
+    if (undefined) continue
+    undefined.e
+}
diff --git a/js/src/jsopcode.cpp b/js/src/jsopcode.cpp
index 3061c3f1637..1b262d7d26e 100644
--- a/js/src/jsopcode.cpp
+++ b/js/src/jsopcode.cpp
@@ -6431,6 +6431,7 @@ ReconstructPCStack(JSContext *cx, JSScript *script, jsbytecode *target,
             if (0 < jmpoff && pc + jmpoff <= target) {
                 pc += jmpoff;
                 oplen = 0;
+                /* Use the Hidden pc count if we follow the goto */
                 if (hpcdepth != unsigned(-1)) {
                     pcdepth = hpcdepth;
                     hpcdepth = unsigned(-1);
@@ -6438,8 +6439,11 @@ ReconstructPCStack(JSContext *cx, JSScript *script, jsbytecode *target,
                 continue;
             }
 
-            if (!script->hasTrynotes())
+            if (!script->hasTrynotes()) {
+                /* Use the normal pc count if continue after the goto */
+                hpcdepth = unsigned(-1);
                 continue;
+            }
 
             /*
              * If we do not follow a goto we look for another mean to continue