ruby.git/tool/ruby_vm/models/bare_instructions.rb, branch v3_2_11

Lazily move PC with RUBY_VM_CHECK_INTS

2020-12-17T07:06:28+00:00

```
$ benchmark-driver -v --rbenv 'before --jit;after --jit' --repeat-count=12 --alternate --output=all benchmark.yml
before --jit: ruby 3.0.0dev (2020-12-17T06:17:46Z master 3b4d698e0b) +JIT [x86_64-linux]
after --jit: ruby 3.0.0dev (2020-12-17T07:01:48Z master 843abb96f0) +JIT [x86_64-linux]
last_commit=Lazily move PC with RUBY_VM_CHECK_INTS
Calculating -------------------------------------
                                 before --jit           after --jit
Optcarrot Lan_Master.nes    80.29343646660429     83.15779723251525 fps
                            82.26755637885149     85.50197941326810
                            83.50682959728820     88.14657804306270
                            85.01236533133049     88.78201988978667
                            87.81799334561326     88.94841008936447
                            87.88228562393064     89.37925215601926
                            88.06695585889995     89.86143277214475
                            88.84730834922165     90.00773346420887
                            90.46317871213088     90.82603371104014
                            90.96308347148916     91.29797694822179
                            90.97945938504556     91.31086331868738
                            91.57127890154500     91.49949184318844
```

Combine call info and cache to speed up method invocation

2019-10-24T09:03:42+00:00

To perform a regular method call, the VM needs two structs,
`rb_call_info` and `rb_call_cache`. At the moment, we allocate these two
structures in separate buffers. In the worst case, the CPU needs to read
4 cache lines to complete a method call. Putting the two structures
together reduces the maximum number of cache line reads to 2.

Combining the structures also saves 8 bytes per call site as the current
layout uses separate two pointers for the call info and the call cache.
This saves about 2 MiB on Discourse.

This change improves the Optcarrot benchmark at least 3%. For more
details, see attached bugs.ruby-lang.org ticket.

Complications:
 - A new instruction attribute `comptime_sp_inc` is introduced to
 calculate SP increase at compile time without using call caches. At
 compile time, a `TS_CALLDATA` operand points to a call info struct, but
 at runtime, the same operand points to a call data struct. Instruction
 that explicitly define `sp_inc` also need to define `comptime_sp_inc`.
 - MJIT code for copying call cache becomes slightly more complicated.
 - This changes the bytecode format, which might break existing tools.

[Misc #16258]

vm.inc now in C99

2019-01-25T14:09:10+00:00

This changeset modifies the VM generator so that vm.inc is written in
C99.  Also added some comments in _insn_entry.erb so that the
intention of each parts to be made more clear.  I think this improves
overall readability of the generated VM.

Confirmed that the exact same binary is generated before/after this
changeset.


git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@66923 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

delete emacs mode lines [ci skip]

2018-12-27T06:12:09+00:00

These settings are now covered by .dir-locals.el.


git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@66584 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

less verbose code by sharing attribute definitions

2018-10-29T03:21:22+00:00

The idea behind this commit is that handles_sp and leaf are two
concepts that are not mutually independent.  By making one explicitly
depend another, we can reduces the number of lines of codes written,
thus making things concise.


git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@65426 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

bare_instructions.rb: sort attributes [ci skip]

2018-10-29T02:07:52+00:00

This enhances stability of the generated source code (namely
insns_info.inc) across attribute insertion / deletion.  It does
not change the compiled binary at all; just a bit of readability.


git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@65425 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

move canary-related statements into macros

2018-09-13T03:46:46+00:00

This is mostly cosmetic.  Should generate a slightly readable
vm.inc output.


git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@64709 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

bare_instructions.rb: use Hash#fetch to read attr

2018-09-11T14:10:00+00:00

to raise descriptive KeyError instead of NoMethodError in case these
attrs are accidentally removed.

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@64685 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

_mjit_compile_pc_and_sp.erb: skip moving pc

2018-09-11T12:53:52+00:00

when catch_except_p is false and insn.always_leaf? is true (never makes
arbitrary method call in the insn).

On Optcarrot, unfortunately this didn't have measureable performance impact.
But still this is a good direction since it becomes much faster when
marking all insns as always leaf.

bare_instructions.rb: add `#always_leaf?` that indicates the insn can
always be considered as leaf. Using dynamic leaf for JIT would be hard
since it requires to discard outdated code somehow.

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@64683 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

add new instruction attribute called leaf

2018-09-11T09:48:58+00:00

An instruction is leaf if it has no rb_funcall inside.  In order to
check this property, we introduce stack canary which is a random
number collected at runtime.  Stack top is always filled with this
number and checked for stack smashing operations, when VM_CHECK_MODE.
[GH-1947]


git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@64677 b2dd03c8-39d4-4d8f-98ff-823fe69b080e