From 26a029d407be480d791972afb5975cf62c9360a6 Mon Sep 17 00:00:00 2001 From: Daniel Baumann Date: Fri, 19 Apr 2024 02:47:55 +0200 Subject: Adding upstream version 124.0.1. Signed-off-by: Daniel Baumann --- js/src/gdb/mozilla/Root.py | 104 +++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 104 insertions(+) create mode 100644 js/src/gdb/mozilla/Root.py (limited to 'js/src/gdb/mozilla/Root.py') diff --git a/js/src/gdb/mozilla/Root.py b/js/src/gdb/mozilla/Root.py new file mode 100644 index 0000000000..fa80f3fec6 --- /dev/null +++ b/js/src/gdb/mozilla/Root.py @@ -0,0 +1,104 @@ +# 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/. + +# Pretty-printers and utilities for SpiderMonkey rooting templates: +# Rooted, Handle, MutableHandle, etc. + +import mozilla.prettyprinters +from mozilla.prettyprinters import template_pretty_printer + +# Forget any printers from previous loads of this module. +mozilla.prettyprinters.clear_module_printers(__name__) + + +class Common(object): + # Common base class for all the rooting template pretty-printers. All these + # templates have one member holding the referent (or a pointer to it), so + # there's not much to it. + + # The name of the template member holding the referent. + member = "ptr" + + # If True, this is a handle type, and should be dereferenced. If False, + # the template member holds the referent directly. + handle = False + + # If True, we should strip typedefs from our referent type. (Rooted + # uses template magic that gives the referent a noisy type.) + strip_typedefs = False + + # Initialize a pretty-printer for |value|, using |cache|. + # + # If given, |content_printer| is a pretty-printer constructor to use for + # this handle/root/etc.'s referent. Usually, we can just omit this argument + # and let GDB choose a pretty-printer for the referent given its type, but + # when the referent is a typedef of an integral type (say, |jsid| in a + # non-|DEBUG| build), the GNU toolchain (at least) loses the typedef name, + # and all we know about the referent is its fundamental integer type --- + # |JS::Rooted|, for example, appears in GDB as |JS::Rooted| --- + # and we are left with no way to choose a meaningful pretty-printer based on + # the type of the referent alone. However, because we know that the only + # integer type for which |JS::Rooted| is likely to be instantiated is + # |jsid|, we *can* register a pretty-printer constructor for the full + # instantiation |JS::Rooted|. That constructor creates a |JS::Rooted| + # pretty-printer, and explicitly specifies the constructor for the referent, + # using this initializer's |content_printer| argument. + def __init__(self, value, cache, content_printer=None): + self.value = value + self.cache = cache + self.content_printer = content_printer + + def to_string(self): + ptr = self.value[self.member] + if self.handle: + ptr = ptr.dereference() + if self.strip_typedefs: + ptr = ptr.cast(ptr.type.strip_typedefs()) + if self.content_printer: + return self.content_printer(ptr, self.cache).to_string() + else: + # As of 2012-11, GDB suppresses printing pointers in replacement + # values; see http://sourceware.org/ml/gdb/2012-11/msg00055.html + # That means that simply returning the 'ptr' member won't work. + # Instead, just invoke GDB's formatter ourselves. + return str(ptr) + + +@template_pretty_printer("JS::Rooted") +class Rooted(Common): + strip_typedefs = True + + +@template_pretty_printer("JS::Handle") +class Handle(Common): + handle = True + + +@template_pretty_printer("JS::MutableHandle") +class MutableHandle(Common): + handle = True + + +@template_pretty_printer("js::BarrieredBase") +class BarrieredBase(Common): + member = "value" + + +def deref(root): + # Return the referent of a HeapPtr, Rooted, or Handle. + tag = root.type.strip_typedefs().tag + if not tag: + raise TypeError( + "Can't dereference type with no structure tag: %s" % (root.type,) + ) + elif tag.startswith("js::HeapPtr<"): + return root["value"] + elif tag.startswith("JS::Rooted<"): + return root["ptr"] + elif tag.startswith("JS::Handle<"): + return root["ptr"] + elif tag.startswith("js::GCPtr<"): + return root["value"] + else: + raise NotImplementedError("Unrecognized tag: " + tag) -- cgit v1.2.3