diff options
Diffstat (limited to 'Source/JavaScriptCore/dfg/DFGFiltrationResult.h')
| -rw-r--r-- | Source/JavaScriptCore/dfg/DFGFiltrationResult.h | 22 |
1 files changed, 14 insertions, 8 deletions
diff --git a/Source/JavaScriptCore/dfg/DFGFiltrationResult.h b/Source/JavaScriptCore/dfg/DFGFiltrationResult.h index 8c80cea90..20d819546 100644 --- a/Source/JavaScriptCore/dfg/DFGFiltrationResult.h +++ b/Source/JavaScriptCore/dfg/DFGFiltrationResult.h @@ -1,5 +1,5 @@ /* - * Copyright (C) 2013 Apple Inc. All rights reserved. + * Copyright (C) 2013, 2015 Apple Inc. All rights reserved. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions @@ -23,23 +23,29 @@ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. */ -#ifndef DFGFiltrationResult_h -#define DFGFiltrationResult_h - -#include <wtf/Platform.h> +#pragma once #if ENABLE(DFG_JIT) namespace JSC { namespace DFG { +// Tells you if an operation that filters type (i.e. does a type check/speculation) will always +// exit. Formally, this means that the proven type of a value prior to the filter was not +// bottom (i.e. not "clear" or "SpecEmpty") but becomes bottom as a result of executing the +// filter. +// +// Note that per this definition, a filter will not return Contradiction if the node's proven +// type was already bottom. This is necessary because we have this yucky convention of using +// a proven type of bottom for nodes that don't hold JS values, like Phi nodes in ThreadedCPS +// and storage nodes. enum FiltrationResult { + // Means that this operation may not always exit. FiltrationOK, + + // Means that this operation will always exit. Contradiction }; } } // namespace JSC::DFG #endif // ENABLE(DFG_JIT) - -#endif // DFGFiltrationResult_h - |