ruby/yjit.rb

280 строки
9.9 KiB
Ruby

# frozen_string_literal: true
# This module allows for introspection of YJIT, CRuby's experimental in-process
# just-in-time compiler. This module exists only to help develop YJIT, as such,
# everything in the module is highly implementation specific and comes with no
# API stability guarantee whatsoever.
#
# This module may not exist if YJIT does not support the particular platform
# for which CRuby is built. There is also no API stability guarantee as to in
# what situations this module is defined.
module RubyVM::YJIT
if defined?(Disasm)
def self.disasm(iseq, tty: $stdout && $stdout.tty?)
iseq = RubyVM::InstructionSequence.of(iseq)
blocks = blocks_for(iseq)
return if blocks.empty?
str = String.new
str << iseq.disasm
str << "\n"
# Sort the blocks by increasing addresses
sorted_blocks = blocks.sort_by(&:address)
highlight = ->(str) {
if tty
"\x1b[1m#{str}\x1b[0m"
else
str
end
}
cs = Disasm.new
sorted_blocks.each_with_index do |block, i|
str << "== BLOCK #{i+1}/#{blocks.length}: #{block.code.length} BYTES, ISEQ RANGE [#{block.iseq_start_index},#{block.iseq_end_index}) ".ljust(80, "=")
str << "\n"
comments = comments_for(block.address, block.address + block.code.length)
comment_idx = 0
cs.disasm(block.code, block.address).each do |i|
while (comment = comments[comment_idx]) && comment.address <= i.address
str << " ; #{highlight.call(comment.comment)}\n"
comment_idx += 1
end
str << sprintf(
" %<address>08x: %<instruction>s\t%<details>s\n",
address: i.address,
instruction: i.mnemonic,
details: i.op_str
)
end
end
block_sizes = blocks.map { |block| block.code.length }
total_bytes = block_sizes.sum
str << "\n"
str << "Total code size: #{total_bytes} bytes"
str << "\n"
str
end
def self.comments_for(start_address, end_address)
Primitive.comments_for(start_address, end_address)
end
def self.graphviz_for(iseq)
iseq = RubyVM::InstructionSequence.of(iseq)
cs = Disasm.new
highlight = ->(comment) { "<b>#{comment}</b>" }
linebreak = "<br align=\"left\"/>\n"
buff = +''
blocks = blocks_for(iseq).sort_by(&:id)
buff << "digraph g {\n"
# Write the iseq info as a legend
buff << " legend [shape=record fontsize=\"30\" fillcolor=\"lightgrey\" style=\"filled\"];\n"
buff << " legend [label=\"{ Instruction Disassembly For: | {#{iseq.base_label}@#{iseq.absolute_path}:#{iseq.first_lineno}}}\"];\n"
# Subgraph contains disassembly
buff << " subgraph disasm {\n"
buff << " node [shape=record fontname=\"courier\"];\n"
buff << " edge [fontname=\"courier\" penwidth=3];\n"
blocks.each do |block|
disasm = disasm_block(cs, block, highlight)
# convert newlines to breaks that graphviz understands
disasm.gsub!(/\n/, linebreak)
# strip leading whitespace
disasm.gsub!(/^\s+/, '')
buff << "b#{block.id} [label=<#{disasm}>];\n"
buff << block.outgoing_ids.map { |id|
next_block = blocks.bsearch { |nb| id <=> nb.id }
if next_block.address == (block.address + block.code.length)
"b#{block.id} -> b#{id}[label=\"Fall\"];"
else
"b#{block.id} -> b#{id}[label=\"Jump\" style=dashed];"
end
}.join("\n")
buff << "\n"
end
buff << " }"
buff << "}"
buff
end
def self.disasm_block(cs, block, highlight)
comments = comments_for(block.address, block.address + block.code.length)
comment_idx = 0
str = +''
cs.disasm(block.code, block.address).each do |i|
while (comment = comments[comment_idx]) && comment.address <= i.address
str << " ; #{highlight.call(comment.comment)}\n"
comment_idx += 1
end
str << sprintf(
" %<address>08x: %<instruction>s\t%<details>s\n",
address: i.address,
instruction: i.mnemonic,
details: i.op_str
)
end
str
end
end
# Return a hash for statistics generated for the --yjit-stats command line option.
# Return nil when option is not passed or unavailable.
def self.runtime_stats
# defined in yjit_iface.c
Primitive.get_yjit_stats
end
# Discard statistics collected for --yjit-stats.
def self.reset_stats!
# defined in yjit_iface.c
Primitive.reset_stats_bang
end
def self.stats_enabled?
Primitive.yjit_stats_enabled_p
end
def self.enabled?
Primitive.cexpr! 'RBOOL(rb_yjit_enabled_p())'
end
def self.simulate_oom!
Primitive.simulate_oom_bang
end
# Avoid calling a method here to not interfere with compilation tests
if Primitive.yjit_stats_enabled_p
at_exit { _print_stats }
end
class << self
private
# Format and print out counters
def _print_stats
stats = runtime_stats
return unless stats
$stderr.puts("***YJIT: Printing YJIT statistics on exit***")
print_counters(stats, prefix: 'send_', prompt: 'method call exit reasons: ')
print_counters(stats, prefix: 'invokesuper_', prompt: 'invokesuper exit reasons: ')
print_counters(stats, prefix: 'leave_', prompt: 'leave exit reasons: ')
print_counters(stats, prefix: 'gbpp_', prompt: 'getblockparamproxy exit reasons: ')
print_counters(stats, prefix: 'getivar_', prompt: 'getinstancevariable exit reasons:')
print_counters(stats, prefix: 'setivar_', prompt: 'setinstancevariable exit reasons:')
print_counters(stats, prefix: 'oaref_', prompt: 'opt_aref exit reasons: ')
print_counters(stats, prefix: 'expandarray_', prompt: 'expandarray exit reasons: ')
print_counters(stats, prefix: 'opt_getinlinecache_', prompt: 'opt_getinlinecache exit reasons: ')
print_counters(stats, prefix: 'invalidate_', prompt: 'invalidation reasons: ')
side_exits = total_exit_count(stats)
total_exits = side_exits + stats[:leave_interp_return]
# Number of instructions that finish executing in YJIT.
# See :count-placement: about the subtraction.
retired_in_yjit = stats[:exec_instruction] - side_exits
# Average length of instruction sequences executed by YJIT
avg_len_in_yjit = retired_in_yjit.to_f / total_exits
# Proportion of instructions that retire in YJIT
total_insns_count = retired_in_yjit + stats[:vm_insns_count]
yjit_ratio_pct = 100.0 * retired_in_yjit.to_f / total_insns_count
# Number of failed compiler invocations
compilation_failure = stats[:compilation_failure]
$stderr.puts "bindings_allocations: " + ("%10d" % stats[:binding_allocations])
$stderr.puts "bindings_set: " + ("%10d" % stats[:binding_set])
$stderr.puts "compilation_failure: " + ("%10d" % compilation_failure) if compilation_failure != 0
$stderr.puts "compiled_iseq_count: " + ("%10d" % stats[:compiled_iseq_count])
$stderr.puts "compiled_block_count: " + ("%10d" % stats[:compiled_block_count])
$stderr.puts "invalidation_count: " + ("%10d" % stats[:invalidation_count])
$stderr.puts "constant_state_bumps: " + ("%10d" % stats[:constant_state_bumps])
$stderr.puts "inline_code_size: " + ("%10d" % stats[:inline_code_size])
$stderr.puts "outlined_code_size: " + ("%10d" % stats[:outlined_code_size])
$stderr.puts "total_exit_count: " + ("%10d" % total_exits)
$stderr.puts "total_insns_count: " + ("%10d" % total_insns_count)
$stderr.puts "vm_insns_count: " + ("%10d" % stats[:vm_insns_count])
$stderr.puts "yjit_insns_count: " + ("%10d" % stats[:exec_instruction])
$stderr.puts "ratio_in_yjit: " + ("%9.1f" % yjit_ratio_pct) + "%"
$stderr.puts "avg_len_in_yjit: " + ("%10.1f" % avg_len_in_yjit)
print_sorted_exit_counts(stats, prefix: "exit_")
end
def print_sorted_exit_counts(stats, prefix:, how_many: 20, left_pad: 4)
exits = []
stats.each do |k, v|
if k.start_with?(prefix)
exits.push [k.to_s.delete_prefix(prefix), v]
end
end
exits = exits.sort_by { |name, count| -count }[0...how_many]
total_exits = total_exit_count(stats)
top_n_total = exits.map { |name, count| count }.sum
top_n_exit_pct = 100.0 * top_n_total / total_exits
$stderr.puts "Top-#{how_many} most frequent exit ops (#{"%.1f" % top_n_exit_pct}% of exits):"
longest_insn_name_len = exits.map { |name, count| name.length }.max
exits.each do |name, count|
padding = longest_insn_name_len + left_pad
padded_name = "%#{padding}s" % name
padded_count = "%10d" % count
percent = 100.0 * count / total_exits
formatted_percent = "%.1f" % percent
$stderr.puts("#{padded_name}: #{padded_count} (#{formatted_percent}%)" )
end
end
def total_exit_count(stats, prefix: "exit_")
total = 0
stats.each do |k,v|
total += v if k.start_with?(prefix)
end
total
end
def print_counters(counters, prefix:, prompt:)
$stderr.puts(prompt)
counters = counters.filter { |key, _| key.start_with?(prefix) }
counters.filter! { |_, value| value != 0 }
counters.transform_keys! { |key| key.to_s.delete_prefix(prefix) }
if counters.empty?
$stderr.puts(" (all relevant counters are zero)")
return
end
counters = counters.to_a
counters.sort_by! { |(_, counter_value)| counter_value }
longest_name_length = counters.max_by { |(name, _)| name.length }.first.length
total = counters.sum { |(_, counter_value)| counter_value }
counters.reverse_each do |(name, value)|
percentage = value.fdiv(total) * 100
$stderr.printf(" %*s %10d (%4.1f%%)\n", longest_name_length, name, value, percentage);
end
end
end
end