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Aaron Patterson tenderlove

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View break_dance.rb
# Have you ever wanted lldb to break in a certain place, but you weren't
# sure where to set the breakpoint? Look no further than this script!
#
# This script creates a chunk of executable code that uses the int3 x86
# instruction. This instruction is defined for use by debuggers, and you can
# read more about it here: https://en.wikipedia.org/wiki/INT_%28x86_instruction%29#INT3
#
# When that instruction is executed, the debugger will halt and you can do
# what you need!
#
View thing.rb
require "objspace"
require "json"
def go x
count = GC.stat(:major_gc_count)
loop do
info = JSON.parse(ObjectSpace.dump(x))
break if info["flags"]["old"]
GC.start
end
View profileyarv.rb
#!/usr/bin/env ruby
require 'pp'
files = {'vm.inc' => [], 'insns.def' => []}
current_insn = nil
current_filename = 'vm.inc'
lineno_offset = 0
IO.foreach('vm.inc') do |line|
case line
when /^INSN_ENTRY\((\w+)\)/
@tenderlove
tenderlove / ngpng.rb
Last active Dec 12, 2020
Simple PNG generation example that only depends on zlib in Ruby
View ngpng.rb
# Not Great PNG class. This is a very simple example of writing a PNG. It
# only supports colors from the color palette stored in `@palette`. This is
# meant to be example code, but I am using it in a program for visualizing
# heap dumps from Ruby.
#
# This is free and unencumbered software released into the public domain.
#
# Anyone is free to copy, modify, publish, use, compile, sell, or
# distribute this software, either in source code form or as a compiled
# binary, for any purpose, commercial or non-commercial, and by any
@tenderlove
tenderlove / out.sh-session
Last active Dec 4, 2020
muck with RbConfig before RubyGems can
View out.sh-session
[aaron@tc-lan-adapter ~]$ cat x.rb
require "rbconfig"
# Change the compiler to "aarons-compiler"
RbConfig::CONFIG["CC"] = "aarons-compiler"
[aaron@tc-lan-adapter ~]$ RUBYOPT='-I/Users/aaron -rx' gem install sqlite3
Building native extensions. This could take a while...
ERROR: Error installing sqlite3:
ERROR: Failed to build gem native extension.
View right_side.stl
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View foo.c
page_body = (struct heap_page_body *)rb_aligned_malloc(HEAP_PAGE_ALIGN, HEAP_PAGE_SIZE);
/* cut.. */
page = calloc1(sizeof(struct heap_page));
/* cut.. */
assert((getpagesize() * 4) == HEAP_PAGE_ALIGN);
intptr_t page_body_end = (intptr_t)page_body + (getpagesize() * 4);
View foo.c
page_body = (struct heap_page_body *)rb_aligned_malloc(HEAP_PAGE_ALIGN, HEAP_PAGE_SIZE);
/* cut.. */
page = calloc1(sizeof(struct heap_page));
View read-barrier-code.rb
def segv_handler(info)
# Only triggered if someone tried to read from a MOVED location
move_all_objects_back(find_page(info.read_address))
end
def compact
register_segv_handler :segv_handler
ruby_heap.pages.each do |page|
move_objects_on(page)
View foo.c
REQUIRED_SIZE_BY_MALLOC = (sizeof(size_t) * 5),
HEAP_PAGE_SIZE = (HEAP_PAGE_ALIGN - REQUIRED_SIZE_BY_MALLOC),