ruby.git/ext/coverage/coverage.c, branch ruby_2_7

Revert https://github.com/ruby/ruby/pull/2486

2019-10-03T03:45:24+00:00

This reverts commits: 10d6a3aca7 8ba48c1b85 fba8627dc1 dd883de5ba
6c6a25feca 167e6b48f1 7cb96d41a5 3207979278 595b3c4fdd 1521f7cf89
c11c5e69ac cf33608203 3632a812c0 f56506be0d 86427a3219 .

The reason for the revert is that we observe ABA problem around
inline method cache.  When a cache misshits, we search for a
method entry.  And if the entry is identical to what was cached
before, we reuse the cache.  But the commits we are reverting here
introduced situations where a method entry is freed, then the
identical memory region is used for another method entry.  An
inline method cache cannot detect that ABA.

Here is a code that reproduce such situation:

```ruby
require 'prime'

class << Integer
  alias org_sqrt sqrt
  def sqrt(n)
    raise
  end

  GC.stress = true
  Prime.each(7*37){} rescue nil # <- Here we populate CC
  class << Object.new; end

  # These adjacent remove-then-alias maneuver
  # frees a method entry, then immediately
  # reuses it for another.
  remove_method :sqrt
  alias sqrt org_sqrt
end

Prime.each(7*37).to_a # <- SEGV
```

refactor constify most of rb_method_entry_t

2019-09-30T01:26:38+00:00

Now that we have eliminated most destructive operations over the
rb_method_entry_t / rb_callable_method_entry_t, let's make them
mostly immutabe and mark them const.

One exception is rb_export_method(), which destructively modifies
visibilities of method entries.  I have left that operation as is
because I suspect that destructiveness is the nature of that
function.

* expand tabs.

2019-07-02T17:13:25+00:00

Use rb_ident_hash_new instead of rb_hash_new_compare_by_id

2019-07-02T17:09:01+00:00

The latter is same as the former, removed the duplicate function.

* expand tabs.

2018-10-20T05:33:13+00:00

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@65196 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

ext/coverage/: add the oneshot mode

2018-10-20T05:33:04+00:00

This patch introduces "oneshot_lines" mode for `Coverage.start`, which
checks "whether each line was executed at least once or not", instead of
"how many times each line was executed".  A hook for each line is fired
at most once, and after it is fired, the hook flag was removed; it runs
with zero overhead.

See [Feature #15022] in detail.

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@65195 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

ext/coverage/coverage.c: remove COVERAGE_EXPERIMENTAL_MODE

2017-12-12T00:20:58+00:00

A NEWS entry is also added.

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@61129 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

ext/coverage/coverage.c: method coverage has column info. of method def.

2017-12-05T08:56:51+00:00

This change makes method coverage result have not only first lineno of
method defintion, but also code range (i.e. first lineno, first column,
last lineno, and last column).

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@61026 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

vm_core.h (rb_iseq_locatoin_t): add a field `code_range`

2017-12-05T08:56:50+00:00

This change makes each ISeq keep NODE's code range.  This information is
needed for method coverage.

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@61025 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

Revamp method coverage to support define_method

2017-12-05T07:16:42+00:00

Traditionally, method coverage measurement was implemented by inserting
`trace2` instruction to the head of method iseq.  So, it just measured
methods defined by `def` keyword.

This commit drastically changes the measuring mechanism of method
coverage; at `RUBY_EVENT_CALL`, it keeps a hash from rb_method_entry_t*
to runs (i.e., it counts the runs per method entry), and at
`Coverage.result`, it creates the result hash by enumerating all
`rb_method_entry_t*` objects (by `ObjectSpace.each_object`).

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@61023 b2dd03c8-39d4-4d8f-98ff-823fe69b080e