We already weren't creating a scope for them. They're generally pretty isolated
and are just used for holding functions that get cloned into other scopes.
Apparently mccr8 once found an edge from an nsXULPrototypeDocument scope into
another scope, but I don't think that should really break anything.
This patch enables sharing of an nsAttrValue's MiscContainer between nodes for style rules. MiscContainers of type eCSSStyleRule are now refcounted (with some clever struct packing to ensure that the amount of memory allocated for MiscContainer remains unchanged on 32 and 64 bit). This infrastructure can be used to share most MiscContainer types in the future if we find advantages to sharing other types than just eCSSStyleRuley. A cache mapping strings to MiscContainers has been added to nsHTMLCSSStyleSheet. MiscContainers can be shared between nsAttrValues when one nsAttrValue is SetTo another nsAttrValue or when there is a cache hit in this cache. This patch also adds the ability to tell a style rule that it belongs to an nsHTMLCSSStyleSheet, with appropriate accessor functions to separate that from the existing case of belonging to an nsCSSStyleSheet.
The primary use case is to reduce memory use for pages that have lots of inline style attributes with the same value. This can happen easily with large pages that are automatically generated. An (admittedly pathological) testcase in Bug 686975 sees over 250 MB of memory savings with this change. Reusing the same MiscContainer for multiple nodes saves the overhead of maintaining separate copies of the string containing the serialized value of the style attribute and of creating separate style rules for each node. Eliminating duplicate style rules enables further savings in layout through style context sharing. The testcase sees the amount of memory used by style contexts go from over 250 MB to 10 KB.
Because the cache is based on the text value of the style attribute, it will not handle attributes that have different text values but are parsed into identical style rules. We also do not attempt to share MiscContainers when the node's base URI differs from the document URI. The effect of these limitations is expected to be low.
This patch actually converts over most of the existing native CC classes
to use the participant. This is done by converting them to use
the newly generalized nsCycleCollectingAutoRefCnt instead of their usual
ref count.
This is mostly a matter of defining new macros defining AddRef() and Release()
for native CC classes with the CC ref count.
nsTimeout is left as a legacy native CC class because it is a weird class,
but hopefully eventually it too can be converted over. See bug 774874.
In the new setup, all per-interface DOM binding files are exported into
mozilla/dom. General files not specific to an interface are also exported into
mozilla/dom.
In terms of namespaces, most things now live in mozilla::dom. Each interface
Foo that has generated code has a mozilla::dom::FooBinding namespace for said
generated code (and possibly a mozilla::bindings::FooBinding_workers if there's
separate codegen for workers).
IDL enums are a bit weird: since the name of the enum and the names of its
entries all end up in the same namespace, we still generate a C++ namespace
with the name of the IDL enum type with "Values" appended to it, with a
::valuelist inside for the actual C++ enum. We then typedef
EnumFooValues::valuelist to EnumFoo. That makes it a bit more difficult to
refer to the values, but means that values from different enums don't collide
with each other.
The enums with the proto and constructor IDs in them now live under the
mozilla::dom::prototypes and mozilla::dom::constructors namespaces respectively.
Again, this lets us deal sanely with the whole "enum value names are flattened
into the namespace the enum is in" deal.
The main benefit of this setup (and the reason "Binding" got appended to the
per-interface namespaces) is that this way "using mozilla::dom" should Just
Work for consumers and still allow C++ code to sanely use the IDL interface
names for concrete classes, which is fairly desirable.
--HG--
rename : dom/bindings/Utils.cpp => dom/bindings/BindingUtils.cpp
rename : dom/bindings/Utils.h => dom/bindings/BindingUtils.h
This part changes the signatures for various finalization API to take
not JSContext* but rather either JSFreeOp structure or its
library-private counterpart FreeOp. These structures wrap parameters
that are passed to the finalizers removing most of explicit dependencies
on JSContext in the finalization code.
The patch shrinks the API presented in jsxdrapi.h down to 4 functions to
encode/decode scripts and interpreted functions to/from the memory. The
newly introduced implementation header vm/Xdr.h replaces the former
JSXDRState with the template class XDRState parametrized by the enum
type with two constants, XDR_ENCODE and XDR_DECODE. This way a compiler
can fully eliminate the former runtime checks for the decoding/encoding
mode. As a drawback this required to explicitly instantiate the xdr
implementation as I do not want to put all the xdr code to header files.
The memory-only XDR allows to avoid coping filename and to-be-atomized
chars to a temporary buffer as the code can just access the buffer
directly. Another change is that new XDRScript takes as a parameter its
parent script. This allowed to avoid keeping filename in XDRState and
simplify the filename management.
Another change is the removal of JS_HAS_HDR. As CloneScript uses XDR to
copy a script, JS_HAS_XDR cannot be disabled.
--HG--
rename : js/src/jsxdrapi.cpp => js/src/vm/Xdr.cpp
extra : rebase_source : f8f1536a86b7c3fe7296a16b6677bd21664af98a
The patch shrinks the API presented in jsxdrapi.h down to 4 functions to
encode/decode scripts and interpreted functions to/from the memory. The
newly introduced implementation header vm/Xdr.h replaces the former
JSXDRState with the template class XDRState parametrized by the enum
type with two constants, XDR_ENCODE and XDR_DECODE. This way a compiler
can fully eliminate the former runtime checks for the decoding/encoding
mode. As a drawback this required to explicitly instantiate the xdr
implementation as I do not want to put all the xdr code to header files.
The memory-only XDR allows to avoid coping filename and to-be-atomized
chars to a temporary buffer as the code can just access the buffer
directly. Another change is that new XDRScript takes as a parameter its
parent script. This allowed to avoid keeping filename in XDRState and
simplify the filename management.
Another change is the removal of JS_HAS_HDR. As CloneScript uses XDR to
copy a script, JS_HAS_XDR cannot be disabled.
--HG--
rename : js/src/jsxdrapi.cpp => js/src/vm/Xdr.cpp
The patch shrinks the API presented in jsxdrapi.h down to 4 functions to
encode/decode scripts and interpreted functions to/from the memory. The
newly introduced implementation header vm/Xdr.h replaces the former
JSXDRState with the template class XDRState parametrized by the enum
type with two constants, XDR_ENCODE and XDR_DECODE. This way a compiler
can fully eliminate the former runtime checks for the decoding/encoding
mode. As a drawback this required to explicitly instantiate the xdr
implementation as I do not want to put all the xdr code to header files.
The memory-only XDR allows to avoid coping filename and to-be-atomized
chars to a temporary buffer as the code can just access the buffer
directly. Another change is that new XDRScript takes as a parameter its
parent script. This allowed to avoid keeping filename in XDRState and
simplify the filename management.
Another change is the removal of JS_HAS_HDR. As CloneScript uses XDR to
copy a script, JS_HAS_XDR cannot be disabled.
--HG--
rename : js/src/jsxdrapi.cpp => js/src/vm/Xdr.cpp