Optimize access to the global object from a function that uses eval

https://bugs.webkit.org/show_bug.cgi?id=38644

Reviewed by Gavin Barraclough.

JavaScriptCore:

Fix bug where cross scope access to a global var (vs. property) would
be allowed without checking for intervening dynamic scopes.

* bytecompiler/BytecodeGenerator.cpp:
(JSC::BytecodeGenerator::emitResolve):

LayoutTests:

Add test case to ensure we don't incorrectly allow dynamic scopes
to be skipped when doing direct var access.

* fast/js/global-resolve-through-eval-expected.txt: Added.
* fast/js/global-resolve-through-eval.html: Added.
* fast/js/script-tests/global-resolve-through-eval.js: Added.
(accessGlobal):
(accessLocal):

git-svn-id: svn://svn.chromium.org/blink/trunk@58993 bbb929c8-8fbe-4397-9dbb-9b2b20218538

1 files changed, 12 insertions, 0 deletions

diff --git a/third_party/WebKit/LayoutTests/fast/js/script-tests/global-resolve-through-eval.js b/third_party/WebKit/LayoutTests/fast/js/script-tests/global-resolve-through-eval.js
new file mode 100644
index 0000000..f8a2cf1
--- /dev/null
+++ b/third_party/WebKit/LayoutTests/fast/js/script-tests/global-resolve-through-eval.js
@@ -0,0 +1,12 @@
+description("Make sure we do a correct property resolution of a global object property when contained by eval.");
+
+var pass = false;
+
+var accessGlobal = (function() { return eval("var pass=true; (function(){ return pass; })"); })();
+var accessLocal = (function() { var pass = false; return (function() { return eval("var pass=true; (function(){ return pass; })"); })(); })();
+
+shouldBeTrue("accessGlobal()");
+shouldBeTrue("accessLocal()");
+
+
+var successfullyParsed = true;