diff options
author | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-19 01:47:29 +0000 |
---|---|---|
committer | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-19 01:47:29 +0000 |
commit | 0ebf5bdf043a27fd3dfb7f92e0cb63d88954c44d (patch) | |
tree | a31f07c9bcca9d56ce61e9a1ffd30ef350d513aa /js/public/GCAnnotations.h | |
parent | Initial commit. (diff) | |
download | firefox-esr-0ebf5bdf043a27fd3dfb7f92e0cb63d88954c44d.tar.xz firefox-esr-0ebf5bdf043a27fd3dfb7f92e0cb63d88954c44d.zip |
Adding upstream version 115.8.0esr.upstream/115.8.0esr
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'js/public/GCAnnotations.h')
-rw-r--r-- | js/public/GCAnnotations.h | 116 |
1 files changed, 116 insertions, 0 deletions
diff --git a/js/public/GCAnnotations.h b/js/public/GCAnnotations.h new file mode 100644 index 0000000000..b952bae3ff --- /dev/null +++ b/js/public/GCAnnotations.h @@ -0,0 +1,116 @@ +/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- + * vim: set ts=8 sts=2 et sw=2 tw=80: + * This Source Code Form is subject to the terms of the Mozilla Public + * License, v. 2.0. If a copy of the MPL was not distributed with this + * file, You can obtain one at http://mozilla.org/MPL/2.0/. */ + +#ifndef js_GCAnnotations_h +#define js_GCAnnotations_h + +// Set of annotations for the rooting hazard analysis, used to categorize types +// and functions. +#ifdef XGILL_PLUGIN + +# define JS_EXPECT_HAZARDS __attribute__((annotate("Expect Hazards"))) + +// Mark a type as being a GC thing (eg js::gc::Cell has this annotation). +# define JS_HAZ_GC_THING __attribute__((annotate("GC Thing"))) + +// Mark a type as holding a pointer to a GC thing (eg JS::Value has this +// annotation.) "Inherited" by templatized types with +// MOZ_INHERIT_TYPE_ANNOTATIONS_FROM_TEMPLATE_ARGS. +# define JS_HAZ_GC_POINTER __attribute__((annotate("GC Pointer"))) + +// Same as JS_HAZ_GC_POINTER, except additionally treat pointers to these +// as GC pointers themselves in order to check references to them, since +// the analysis cannot distinguish between pointers and references. +# define JS_HAZ_GC_REF __attribute__((annotate("GC Pointer or Reference"))) + +// Mark a type as a rooted pointer, suitable for use on the stack (eg all +// Rooted<T> instantiations should have this.) "Inherited" by templatized types +// with MOZ_INHERIT_TYPE_ANNOTATIONS_FROM_TEMPLATE_ARGS. +# define JS_HAZ_ROOTED __attribute__((annotate("Rooted Pointer"))) + +// Mark a type as something that should not be held live across a GC, but which +// is not itself a GC pointer. Note that this property is *not* inherited by +// templatized types with MOZ_INHERIT_TYPE_ANNOTATIONS_FROM_TEMPLATE_ARGS. +# define JS_HAZ_GC_INVALIDATED __attribute__((annotate("Invalidated by GC"))) + +// Mark a class as a base class of rooted types, eg CustomAutoRooter. All +// descendants of this class will be considered rooted, though classes that +// merely contain these as a field member will not be. "Inherited" by +// templatized types with MOZ_INHERIT_TYPE_ANNOTATIONS_FROM_TEMPLATE_ARGS +# define JS_HAZ_ROOTED_BASE __attribute__((annotate("Rooted Base"))) + +// Mark a type that would otherwise be considered a GC Pointer (eg because it +// contains a JS::Value field) as a non-GC pointer. It is handled almost the +// same in the analysis as a rooted pointer, except it will not be reported as +// an unnecessary root if used across a GC call. This should rarely be used, +// but makes sense for something like ErrorResult, which only contains a GC +// pointer when it holds an exception (and it does its own rooting, +// conditionally.) +# define JS_HAZ_NON_GC_POINTER \ + __attribute__((annotate("Suppressed GC Pointer"))) + +// Mark a function as something that runs a garbage collection, potentially +// invalidating GC pointers. +# define JS_HAZ_GC_CALL __attribute__((annotate("GC Call"))) + +// Mark an RAII class as suppressing GC within its scope. +# define JS_HAZ_GC_SUPPRESSED __attribute__((annotate("Suppress GC"))) + +// Mark a function as one that can run script if called. This obviously +// subsumes JS_HAZ_GC_CALL, since anything that can run script can GC.` +# define JS_HAZ_CAN_RUN_SCRIPT __attribute__((annotate("Can run script"))) + +// Mark a function as able to call JSNatives. Otherwise, JSNatives don't show +// up in the callgraph. This doesn't matter for the can-GC analysis, but it is +// very nice for other uses of the callgraph. +# define JS_HAZ_JSNATIVE_CALLER __attribute__((annotate("Calls JSNatives"))) + +// Mark a variable as being "GC safe", i.e., it does not contain any +// invalidatable pointers at the current point in the code. A typical +// example might be a collection containing GC pointers, which at the +// present time is empty. This property is only temporary; the next use +// of the variable will invalidate it (on the assumption that a GC pointer +// might be added to it.) Try to use this as early as possible, probably +// immediately after construction, so that if future mutations through +// the variable are added, they won't be covered by the annotation. +# define JS_HAZ_VALUE_IS_GC_SAFE(var) JS::detail::MarkVariableAsGCSafe(var) + +#else + +# define JS_EXPECT_HAZARDS +# define JS_HAZ_GC_THING +# define JS_HAZ_GC_POINTER +# define JS_HAZ_GC_REF +# define JS_HAZ_ROOTED +# define JS_HAZ_GC_INVALIDATED +# define JS_HAZ_ROOTED_BASE +# define JS_HAZ_NON_GC_POINTER +# define JS_HAZ_GC_CALL +# define JS_HAZ_GC_SUPPRESSED +# define JS_HAZ_CAN_RUN_SCRIPT +# define JS_HAZ_JSNATIVE_CALLER +# define JS_HAZ_VALUE_IS_GC_SAFE(var) + +#endif + +#ifdef XGILL_PLUGIN + +// Implemented by passing variable to a dummy function so that it shows up +// in the control flow graph. +namespace JS { +namespace detail { + +template <typename T> +static inline void MarkVariableAsGCSafe(T& var) { + asm(""); +} + +} // namespace detail +} // namespace JS + +#endif + +#endif /* js_GCAnnotations_h */ |