<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.1//EN"
"http://www.w3.org/TR/xhtml11/DTD/xhtml11.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<head><meta http-equiv="content-type" content="text/html; charset=utf-8" />
<title>[208819] trunk/Source/JavaScriptCore</title>
</head>
<body>
<style type="text/css"><!--
#msg dl.meta { border: 1px #006 solid; background: #369; padding: 6px; color: #fff; }
#msg dl.meta dt { float: left; width: 6em; font-weight: bold; }
#msg dt:after { content:':';}
#msg dl, #msg dt, #msg ul, #msg li, #header, #footer, #logmsg { font-family: verdana,arial,helvetica,sans-serif; font-size: 10pt; }
#msg dl a { font-weight: bold}
#msg dl a:link { color:#fc3; }
#msg dl a:active { color:#ff0; }
#msg dl a:visited { color:#cc6; }
h3 { font-family: verdana,arial,helvetica,sans-serif; font-size: 10pt; font-weight: bold; }
#msg pre { overflow: auto; background: #ffc; border: 1px #fa0 solid; padding: 6px; }
#logmsg { background: #ffc; border: 1px #fa0 solid; padding: 1em 1em 0 1em; }
#logmsg p, #logmsg pre, #logmsg blockquote { margin: 0 0 1em 0; }
#logmsg p, #logmsg li, #logmsg dt, #logmsg dd { line-height: 14pt; }
#logmsg h1, #logmsg h2, #logmsg h3, #logmsg h4, #logmsg h5, #logmsg h6 { margin: .5em 0; }
#logmsg h1:first-child, #logmsg h2:first-child, #logmsg h3:first-child, #logmsg h4:first-child, #logmsg h5:first-child, #logmsg h6:first-child { margin-top: 0; }
#logmsg ul, #logmsg ol { padding: 0; list-style-position: inside; margin: 0 0 0 1em; }
#logmsg ul { text-indent: -1em; padding-left: 1em; }#logmsg ol { text-indent: -1.5em; padding-left: 1.5em; }
#logmsg > ul, #logmsg > ol { margin: 0 0 1em 0; }
#logmsg pre { background: #eee; padding: 1em; }
#logmsg blockquote { border: 1px solid #fa0; border-left-width: 10px; padding: 1em 1em 0 1em; background: white;}
#logmsg dl { margin: 0; }
#logmsg dt { font-weight: bold; }
#logmsg dd { margin: 0; padding: 0 0 0.5em 0; }
#logmsg dd:before { content:'\00bb';}
#logmsg table { border-spacing: 0px; border-collapse: collapse; border-top: 4px solid #fa0; border-bottom: 1px solid #fa0; background: #fff; }
#logmsg table th { text-align: left; font-weight: normal; padding: 0.2em 0.5em; border-top: 1px dotted #fa0; }
#logmsg table td { text-align: right; border-top: 1px dotted #fa0; padding: 0.2em 0.5em; }
#logmsg table thead th { text-align: center; border-bottom: 1px solid #fa0; }
#logmsg table th.Corner { text-align: left; }
#logmsg hr { border: none 0; border-top: 2px dashed #fa0; height: 1px; }
#header, #footer { color: #fff; background: #636; border: 1px #300 solid; padding: 6px; }
#patch { width: 100%; }
#patch h4 {font-family: verdana,arial,helvetica,sans-serif;font-size:10pt;padding:8px;background:#369;color:#fff;margin:0;}
#patch .propset h4, #patch .binary h4 {margin:0;}
#patch pre {padding:0;line-height:1.2em;margin:0;}
#patch .diff {width:100%;background:#eee;padding: 0 0 10px 0;overflow:auto;}
#patch .propset .diff, #patch .binary .diff {padding:10px 0;}
#patch span {display:block;padding:0 10px;}
#patch .modfile, #patch .addfile, #patch .delfile, #patch .propset, #patch .binary, #patch .copfile {border:1px solid #ccc;margin:10px 0;}
#patch ins {background:#dfd;text-decoration:none;display:block;padding:0 10px;}
#patch del {background:#fdd;text-decoration:none;display:block;padding:0 10px;}
#patch .lines, .info {color:#888;background:#fff;}
--></style>
<div id="msg">
<dl class="meta">
<dt>Revision</dt> <dd><a href="http://trac.webkit.org/projects/webkit/changeset/208819">208819</a></dd>
<dt>Author</dt> <dd>mark.lam@apple.com</dd>
<dt>Date</dt> <dd>2016-11-16 15:18:11 -0800 (Wed, 16 Nov 2016)</dd>
</dl>
<h3>Log Message</h3>
<pre>ExceptionFuzz functions should use its client's ThrowScope.
https://bugs.webkit.org/show_bug.cgi?id=164834
Reviewed by Geoffrey Garen.
This is because ExceptionFuzz's purpose is to throw exceptions from its client at
exception check sites. Using the client's ThrowScope solves 2 problems:
1. If ExceptionFuzz instantiates its own ThrowScope, the simulated throw will be
mis-attributed to ExceptionFuzz when it should be attributed to its client.
2. One way exception scope verification works is by having ThrowScopes assert
that there are no unchecked simulated exceptions when the ThrowScope is
instantiated. However, ExceptionFuzz necessarily works by inserting
doExceptionFuzzingIfEnabled() in between a ThrowScope that simulated a throw
and an exception check. If we declare a ThrowScope in ExceptionFuzz's code,
we will be instantiating the ThrowScope between the point where a simulated
throw occurs and where the needed exception check can occur. Hence, having
ExceptionFuzz instantiate its own ThrowScope will fail exception scope
verification every time.
Changing ExceptionFuzz to use its client's ThrowScope resolves both problems.
Also fixed the THROW() macro in CommonSlowPaths.cpp to use the ThrowScope that
already exists in every slow path function instead of creating a new one.
* jit/JITOperations.cpp:
* llint/LLIntSlowPaths.cpp:
* runtime/CommonSlowPaths.cpp:
* runtime/ExceptionFuzz.cpp:
(JSC::doExceptionFuzzing):
* runtime/ExceptionFuzz.h:
(JSC::doExceptionFuzzingIfEnabled):</pre>
<h3>Modified Paths</h3>
<ul>
<li><a href="#trunkSourceJavaScriptCoreChangeLog">trunk/Source/JavaScriptCore/ChangeLog</a></li>
<li><a href="#trunkSourceJavaScriptCorejitJITOperationscpp">trunk/Source/JavaScriptCore/jit/JITOperations.cpp</a></li>
<li><a href="#trunkSourceJavaScriptCorellintLLIntSlowPathscpp">trunk/Source/JavaScriptCore/llint/LLIntSlowPaths.cpp</a></li>
<li><a href="#trunkSourceJavaScriptCoreruntimeCommonSlowPathscpp">trunk/Source/JavaScriptCore/runtime/CommonSlowPaths.cpp</a></li>
<li><a href="#trunkSourceJavaScriptCoreruntimeExceptionFuzzcpp">trunk/Source/JavaScriptCore/runtime/ExceptionFuzz.cpp</a></li>
<li><a href="#trunkSourceJavaScriptCoreruntimeExceptionFuzzh">trunk/Source/JavaScriptCore/runtime/ExceptionFuzz.h</a></li>
</ul>
</div>
<div id="patch">
<h3>Diff</h3>
<a id="trunkSourceJavaScriptCoreChangeLog"></a>
<div class="modfile"><h4>Modified: trunk/Source/JavaScriptCore/ChangeLog (208818 => 208819)</h4>
<pre class="diff"><span>
<span class="info">--- trunk/Source/JavaScriptCore/ChangeLog 2016-11-16 23:17:26 UTC (rev 208818)
+++ trunk/Source/JavaScriptCore/ChangeLog 2016-11-16 23:18:11 UTC (rev 208819)
</span><span class="lines">@@ -1,3 +1,39 @@
</span><ins>+2016-11-16 Mark Lam <mark.lam@apple.com>
+
+ ExceptionFuzz functions should use its client's ThrowScope.
+ https://bugs.webkit.org/show_bug.cgi?id=164834
+
+ Reviewed by Geoffrey Garen.
+
+ This is because ExceptionFuzz's purpose is to throw exceptions from its client at
+ exception check sites. Using the client's ThrowScope solves 2 problems:
+
+ 1. If ExceptionFuzz instantiates its own ThrowScope, the simulated throw will be
+ mis-attributed to ExceptionFuzz when it should be attributed to its client.
+
+ 2. One way exception scope verification works is by having ThrowScopes assert
+ that there are no unchecked simulated exceptions when the ThrowScope is
+ instantiated. However, ExceptionFuzz necessarily works by inserting
+ doExceptionFuzzingIfEnabled() in between a ThrowScope that simulated a throw
+ and an exception check. If we declare a ThrowScope in ExceptionFuzz's code,
+ we will be instantiating the ThrowScope between the point where a simulated
+ throw occurs and where the needed exception check can occur. Hence, having
+ ExceptionFuzz instantiate its own ThrowScope will fail exception scope
+ verification every time.
+
+ Changing ExceptionFuzz to use its client's ThrowScope resolves both problems.
+
+ Also fixed the THROW() macro in CommonSlowPaths.cpp to use the ThrowScope that
+ already exists in every slow path function instead of creating a new one.
+
+ * jit/JITOperations.cpp:
+ * llint/LLIntSlowPaths.cpp:
+ * runtime/CommonSlowPaths.cpp:
+ * runtime/ExceptionFuzz.cpp:
+ (JSC::doExceptionFuzzing):
+ * runtime/ExceptionFuzz.h:
+ (JSC::doExceptionFuzzingIfEnabled):
+
</ins><span class="cx"> 2016-11-16 Filip Pizlo <fpizlo@apple.com>
</span><span class="cx">
</span><span class="cx"> Slight Octane regression from concurrent GC's eager object zero-fill
</span></span></pre></div>
<a id="trunkSourceJavaScriptCorejitJITOperationscpp"></a>
<div class="modfile"><h4>Modified: trunk/Source/JavaScriptCore/jit/JITOperations.cpp (208818 => 208819)</h4>
<pre class="diff"><span>
<span class="info">--- trunk/Source/JavaScriptCore/jit/JITOperations.cpp 2016-11-16 23:17:26 UTC (rev 208818)
+++ trunk/Source/JavaScriptCore/jit/JITOperations.cpp 2016-11-16 23:18:11 UTC (rev 208819)
</span><span class="lines">@@ -2271,9 +2271,11 @@
</span><span class="cx"> {
</span><span class="cx"> VM* vm = &exec->vm();
</span><span class="cx"> NativeCallFrameTracer tracer(vm, exec);
</span><ins>+ auto scope = DECLARE_THROW_SCOPE(*vm);
+ UNUSED_PARAM(scope);
</ins><span class="cx"> #if COMPILER(GCC_OR_CLANG)
</span><span class="cx"> void* returnPC = __builtin_return_address(0);
</span><del>- doExceptionFuzzing(exec, "JITOperations", returnPC);
</del><ins>+ doExceptionFuzzing(exec, scope, "JITOperations", returnPC);
</ins><span class="cx"> #endif // COMPILER(GCC_OR_CLANG)
</span><span class="cx"> }
</span><span class="cx">
</span></span></pre></div>
<a id="trunkSourceJavaScriptCorellintLLIntSlowPathscpp"></a>
<div class="modfile"><h4>Modified: trunk/Source/JavaScriptCore/llint/LLIntSlowPaths.cpp (208818 => 208819)</h4>
<pre class="diff"><span>
<span class="info">--- trunk/Source/JavaScriptCore/llint/LLIntSlowPaths.cpp 2016-11-16 23:17:26 UTC (rev 208818)
+++ trunk/Source/JavaScriptCore/llint/LLIntSlowPaths.cpp 2016-11-16 23:18:11 UTC (rev 208819)
</span><span class="lines">@@ -108,7 +108,7 @@
</span><span class="cx"> } while (false)
</span><span class="cx">
</span><span class="cx"> #define LLINT_CHECK_EXCEPTION() do { \
</span><del>- doExceptionFuzzingIfEnabled(exec, "LLIntSlowPaths", pc); \
</del><ins>+ doExceptionFuzzingIfEnabled(exec, throwScope, "LLIntSlowPaths", pc); \
</ins><span class="cx"> if (UNLIKELY(throwScope.exception())) { \
</span><span class="cx"> pc = returnToThrow(exec); \
</span><span class="cx"> LLINT_END_IMPL(); \
</span><span class="lines">@@ -169,7 +169,7 @@
</span><span class="cx"> #define LLINT_CALL_CHECK_EXCEPTION(exec, execCallee) do { \
</span><span class="cx"> ExecState* __cce_exec = (exec); \
</span><span class="cx"> ExecState* __cce_execCallee = (execCallee); \
</span><del>- doExceptionFuzzingIfEnabled(__cce_exec, "LLIntSlowPaths/call", nullptr); \
</del><ins>+ doExceptionFuzzingIfEnabled(__cce_exec, throwScope, "LLIntSlowPaths/call", nullptr); \
</ins><span class="cx"> if (UNLIKELY(throwScope.exception())) \
</span><span class="cx"> LLINT_CALL_END_IMPL(0, callToThrow(__cce_execCallee)); \
</span><span class="cx"> } while (false)
</span></span></pre></div>
<a id="trunkSourceJavaScriptCoreruntimeCommonSlowPathscpp"></a>
<div class="modfile"><h4>Modified: trunk/Source/JavaScriptCore/runtime/CommonSlowPaths.cpp (208818 => 208819)</h4>
<pre class="diff"><span>
<span class="info">--- trunk/Source/JavaScriptCore/runtime/CommonSlowPaths.cpp 2016-11-16 23:17:26 UTC (rev 208818)
+++ trunk/Source/JavaScriptCore/runtime/CommonSlowPaths.cpp 2016-11-16 23:18:11 UTC (rev 208819)
</span><span class="lines">@@ -96,14 +96,13 @@
</span><span class="cx"> #define END_IMPL() RETURN_TWO(pc, exec)
</span><span class="cx">
</span><span class="cx"> #define THROW(exceptionToThrow) do { \
</span><del>- auto scope = DECLARE_THROW_SCOPE(vm); \
- throwException(exec, scope, exceptionToThrow); \
</del><ins>+ throwException(exec, throwScope, exceptionToThrow); \
</ins><span class="cx"> RETURN_TO_THROW(exec, pc); \
</span><span class="cx"> END_IMPL(); \
</span><span class="cx"> } while (false)
</span><span class="cx">
</span><span class="cx"> #define CHECK_EXCEPTION() do { \
</span><del>- doExceptionFuzzingIfEnabled(exec, "CommonSlowPaths", pc); \
</del><ins>+ doExceptionFuzzingIfEnabled(exec, throwScope, "CommonSlowPaths", pc); \
</ins><span class="cx"> if (UNLIKELY(throwScope.exception())) { \
</span><span class="cx"> RETURN_TO_THROW(exec, pc); \
</span><span class="cx"> END_IMPL(); \
</span></span></pre></div>
<a id="trunkSourceJavaScriptCoreruntimeExceptionFuzzcpp"></a>
<div class="modfile"><h4>Modified: trunk/Source/JavaScriptCore/runtime/ExceptionFuzz.cpp (208818 => 208819)</h4>
<pre class="diff"><span>
<span class="info">--- trunk/Source/JavaScriptCore/runtime/ExceptionFuzz.cpp 2016-11-16 23:17:26 UTC (rev 208818)
+++ trunk/Source/JavaScriptCore/runtime/ExceptionFuzz.cpp 2016-11-16 23:18:11 UTC (rev 208819)
</span><span class="lines">@@ -36,10 +36,9 @@
</span><span class="cx"> unsigned numberOfExceptionFuzzChecks() { return s_numberOfExceptionFuzzChecks; }
</span><span class="cx">
</span><span class="cx"> // Call this only if you know that exception fuzzing is enabled.
</span><del>-void doExceptionFuzzing(ExecState* exec, const char* where, void* returnPC)
</del><ins>+void doExceptionFuzzing(ExecState* exec, ThrowScope& scope, const char* where, void* returnPC)
</ins><span class="cx"> {
</span><del>- VM& vm = exec->vm();
- auto scope = DECLARE_THROW_SCOPE(vm);
</del><ins>+ VM& vm = scope.vm();
</ins><span class="cx"> ASSERT(Options::useExceptionFuzz());
</span><span class="cx">
</span><span class="cx"> DeferGCForAWhile deferGC(vm.heap);
</span></span></pre></div>
<a id="trunkSourceJavaScriptCoreruntimeExceptionFuzzh"></a>
<div class="modfile"><h4>Modified: trunk/Source/JavaScriptCore/runtime/ExceptionFuzz.h (208818 => 208819)</h4>
<pre class="diff"><span>
<span class="info">--- trunk/Source/JavaScriptCore/runtime/ExceptionFuzz.h 2016-11-16 23:17:26 UTC (rev 208818)
+++ trunk/Source/JavaScriptCore/runtime/ExceptionFuzz.h 2016-11-16 23:18:11 UTC (rev 208819)
</span><span class="lines">@@ -30,16 +30,17 @@
</span><span class="cx"> namespace JSC {
</span><span class="cx">
</span><span class="cx"> class ExecState;
</span><ins>+class ThrowScope;
</ins><span class="cx">
</span><span class="cx"> // Call this only if you know that exception fuzzing is enabled.
</span><del>-void doExceptionFuzzing(ExecState* exec, const char* where, void* returnPC);
</del><ins>+void doExceptionFuzzing(ExecState*, ThrowScope&, const char* where, void* returnPC);
</ins><span class="cx">
</span><span class="cx"> // This is what you should call if you don't know if fuzzing is enabled.
</span><del>-ALWAYS_INLINE void doExceptionFuzzingIfEnabled(ExecState* exec, const char* where, void* returnPC)
</del><ins>+ALWAYS_INLINE void doExceptionFuzzingIfEnabled(ExecState* exec, ThrowScope& scope, const char* where, void* returnPC)
</ins><span class="cx"> {
</span><span class="cx"> if (LIKELY(!Options::useExceptionFuzz()))
</span><span class="cx"> return;
</span><del>- doExceptionFuzzing(exec, where, returnPC);
</del><ins>+ doExceptionFuzzing(exec, scope, where, returnPC);
</ins><span class="cx"> }
</span><span class="cx">
</span><span class="cx"> } // namespace JSC
</span></span></pre>
</div>
</div>
</body>
</html>