mjit_compile.c: merge initial JIT compiler

which has been developed by Takashi Kokubun <takashikkbn@gmail> as
YARV-MJIT. Many of its bugs are fixed by wanabe <s.wanabe@gmail.com>.

This JIT compiler is designed to be a safe migration path to introduce
JIT compiler to MRI. So this commit does not include any bytecode
changes or dynamic instruction modifications, which are done in original
MJIT.

This commit even strips off some aggressive optimizations from
YARV-MJIT, and thus it's slower than YARV-MJIT too. But it's still
fairly faster than Ruby 2.5 in some benchmarks (attached below).

Note that this JIT compiler passes `make test`, `make test-all`, `make
test-spec` without JIT, and even with JIT. Not only it's perfectly safe
with JIT disabled because it does not replace VM instructions unlike
MJIT, but also with JIT enabled it stably runs Ruby applications
including Rails applications.

I'm expecting this version as just "initial" JIT compiler. I have many
optimization ideas which are skipped for initial merging, and you may
easily replace this JIT compiler with a faster one by just replacing
mjit_compile.c. `mjit_compile` interface is designed for the purpose.

common.mk: update dependencies for mjit_compile.c.

internal.h: declare `rb_vm_insn_addr2insn` for MJIT.

vm.c: exclude some definitions if `-DMJIT_HEADER` is provided to
compiler. This avoids to include some functions which take a long time
to compile, e.g. vm_exec_core. Some of the purpose is achieved in
transform_mjit_header.rb (see `IGNORED_FUNCTIONS`) but others are
manually resolved for now. Load mjit_helper.h for MJIT header.
mjit_helper.h: New. This is a file used only by JIT-ed code. I'll
refactor `mjit_call_cfunc` later.
vm_eval.c: add some #ifdef switches to skip compiling some functions
like Init_vm_eval.

win32/mkexports.rb: export thread/ec functions, which are used by MJIT.

include/ruby/defines.h: add MJIT_FUNC_EXPORTED macro alis to clarify
that a function is exported only for MJIT.

array.c: export a function used by MJIT.
bignum.c: ditto.
class.c: ditto.
compile.c: ditto.
error.c: ditto.
gc.c: ditto.
hash.c: ditto.
iseq.c: ditto.
numeric.c: ditto.
object.c: ditto.
proc.c: ditto.
re.c: ditto.
st.c: ditto.
string.c: ditto.
thread.c: ditto.
variable.c: ditto.
vm_backtrace.c: ditto.
vm_insnhelper.c: ditto.
vm_method.c: ditto.

I would like to improve maintainability of function exports, but I
believe this way is acceptable as initial merging if we clarify the
new exports are for MJIT (so that we can use them as TODO list to fix)
and add unit tests to detect unresolved symbols.
I'll add unit tests of JIT compilations in succeeding commits.

Author: Takashi Kokubun <takashikkbn@gmail.com>
Contributor: wanabe <s.wanabe@gmail.com>

Part of [Feature #14235]

---

* Known issues
  * Code generated by gcc is faster than clang. The benchmark may be worse
    in macOS. Following benchmark result is provided by gcc w/ Linux.
  * Performance is decreased when Google Chrome is running
  * JIT can work on MinGW, but it doesn't improve performance at least
    in short running benchmark.
  * Currently it doesn't perform well with Rails. We'll try to fix this
    before release.

---

* Benchmark reslts

Benchmarked with:
Intel 4.0GHz i7-4790K with 16GB memory under x86-64 Ubuntu 8 Cores

- 2.0.0-p0: Ruby 2.0.0-p0
- r62186: Ruby trunk (early 2.6.0), before MJIT changes
- JIT off: On this commit, but without `--jit` option
- JIT on: On this commit, and with `--jit` option

** Optcarrot fps

Benchmark: https://github.com/mame/optcarrot

|         |2.0.0-p0 |r62186   |JIT off  |JIT on   |
|:--------|:--------|:--------|:--------|:--------|
|fps      |37.32    |51.46    |51.31    |58.88    |
|vs 2.0.0 |1.00x    |1.38x    |1.37x    |1.58x    |

** MJIT benchmarks

Benchmark: https://github.com/benchmark-driver/mjit-benchmarks
(Original: https://github.com/vnmakarov/ruby/tree/rtl_mjit_branch/MJIT-benchmarks)

|           |2.0.0-p0 |r62186   |JIT off  |JIT on   |
|:----------|:--------|:--------|:--------|:--------|
|aread      |1.00     |1.09     |1.07     |2.19     |
|aref       |1.00     |1.13     |1.11     |2.22     |
|aset       |1.00     |1.50     |1.45     |2.64     |
|awrite     |1.00     |1.17     |1.13     |2.20     |
|call       |1.00     |1.29     |1.26     |2.02     |
|const2     |1.00     |1.10     |1.10     |2.19     |
|const      |1.00     |1.11     |1.10     |2.19     |
|fannk      |1.00     |1.04     |1.02     |1.00     |
|fib        |1.00     |1.32     |1.31     |1.84     |
|ivread     |1.00     |1.13     |1.12     |2.43     |
|ivwrite    |1.00     |1.23     |1.21     |2.40     |
|mandelbrot |1.00     |1.13     |1.16     |1.28     |
|meteor     |1.00     |2.97     |2.92     |3.17     |
|nbody      |1.00     |1.17     |1.15     |1.49     |
|nest-ntimes|1.00     |1.22     |1.20     |1.39     |
|nest-while |1.00     |1.10     |1.10     |1.37     |
|norm       |1.00     |1.18     |1.16     |1.24     |
|nsvb       |1.00     |1.16     |1.16     |1.17     |
|red-black  |1.00     |1.02     |0.99     |1.12     |
|sieve      |1.00     |1.30     |1.28     |1.62     |
|trees      |1.00     |1.14     |1.13     |1.19     |
|while      |1.00     |1.12     |1.11     |2.41     |

** Discourse's script/bench.rb

Benchmark: https://github.com/discourse/discourse/blob/v1.8.7/script/bench.rb

NOTE: Rails performance was somehow a little degraded with JIT for now.
We should fix this.
(At least I know opt_aref is performing badly in JIT and I have an idea
 to fix it. Please wait for the fix.)

*** JIT off
Your Results: (note for timings- percentile is first, duration is second in millisecs)

categories_admin:
  50: 17
  75: 18
  90: 22
  99: 29
home_admin:
  50: 21
  75: 21
  90: 27
  99: 40
topic_admin:
  50: 17
  75: 18
  90: 22
  99: 32
categories:
  50: 35
  75: 41
  90: 43
  99: 77
home:
  50: 39
  75: 46
  90: 49
  99: 95
topic:
  50: 46
  75: 52
  90: 56
  99: 101

*** JIT on
Your Results: (note for timings- percentile is first, duration is second in millisecs)

categories_admin:
  50: 19
  75: 21
  90: 25
  99: 33
home_admin:
  50: 24
  75: 26
  90: 30
  99: 35
topic_admin:
  50: 19
  75: 20
  90: 25
  99: 30
categories:
  50: 40
  75: 44
  90: 48
  99: 76
home:
  50: 42
  75: 48
  90: 51
  99: 89
topic:
  50: 49
  75: 55
  90: 58
  99: 99

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@62197 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

1 files changed, 20 insertions, 13 deletions

diff --git a/vm_insnhelper.c b/vm_insnhelper.c
index acb7d7999d..bc54acb0a9 100644
--- a/vm_insnhelper.c
+++ b/vm_insnhelper.c
@@ -243,7 +243,8 @@ vm_push_frame(rb_execution_context_t *ec,
     *sp++ = specval     /* ep[-1] / block handler or prev env ptr */;
     *sp   = type;       /* ep[-0] / ENV_FLAGS */
 
-    cfp->ep = sp;
+    /* Store initial value of ep as bp to skip calculation cost of bp on JIT cancellation. */
+    cfp->ep = cfp->bp = sp;
     cfp->sp = sp + 1;
 
 #if VM_DEBUG_BP_CHECK
@@ -1295,6 +1296,18 @@ vm_expandarray(rb_control_frame_t *cfp, VALUE ary, rb_num_t num, int flag)
 
 static VALUE vm_call_general(rb_execution_context_t *ec, rb_control_frame_t *reg_cfp, struct rb_calling_info *calling, const struct rb_call_info *ci, struct rb_call_cache *cc);
 
+MJIT_FUNC_EXPORTED void
+vm_search_method_slowpath(const struct rb_call_info *ci, struct rb_call_cache *cc, VALUE klass)
+{
+    cc->me = rb_callable_method_entry(klass, ci->mid);
+    VM_ASSERT(callable_method_entry_p(cc->me));
+    cc->call = vm_call_general;
+#if OPT_INLINE_METHOD_CACHE
+    cc->method_state = GET_GLOBAL_METHOD_STATE();
+    cc->class_serial = RCLASS_SERIAL(klass);
+#endif
+}
+
 static void
 vm_search_method(const struct rb_call_info *ci, struct rb_call_cache *cc, VALUE recv)
 {
@@ -1312,13 +1325,7 @@ vm_search_method(const struct rb_call_info *ci, struct rb_call_cache *cc, VALUE
     }
     RB_DEBUG_COUNTER_INC(mc_inline_miss);
 #endif
-    cc->me = rb_callable_method_entry(klass, ci->mid);
-    VM_ASSERT(callable_method_entry_p(cc->me));
-    cc->call = vm_call_general;
-#if OPT_INLINE_METHOD_CACHE
-    cc->method_state = GET_GLOBAL_METHOD_STATE();
-    cc->class_serial = RCLASS_SERIAL(klass);
-#endif
+    vm_search_method_slowpath(ci, cc, klass);
 }
 
 static inline int
@@ -1458,7 +1465,7 @@ rb_eql_opt(VALUE obj1, VALUE obj2)
     return opt_eql_func(obj1, obj2, &ci, &cc);
 }
 
-static VALUE vm_call0(rb_execution_context_t *ec, VALUE, ID, int, const VALUE*, const rb_callable_method_entry_t *);
+extern VALUE vm_call0(rb_execution_context_t *ec, VALUE, ID, int, const VALUE*, const rb_callable_method_entry_t *);
 
 static VALUE
 check_match(rb_execution_context_t *ec, VALUE pattern, VALUE target, enum vm_check_match_type type)
@@ -1562,9 +1569,9 @@ static inline VALUE vm_call_method(rb_execution_context_t *ec, rb_control_frame_
 
 static vm_call_handler vm_call_iseq_setup_func(const struct rb_call_info *ci, const int param_size, const int local_size);
 
-static rb_method_definition_t *method_definition_create(rb_method_type_t type, ID mid);
-static void method_definition_set(const rb_method_entry_t *me, rb_method_definition_t *def, void *opts);
-static int rb_method_definition_eq(const rb_method_definition_t *d1, const rb_method_definition_t *d2);
+extern rb_method_definition_t *method_definition_create(rb_method_type_t type, ID mid);
+extern void method_definition_set(const rb_method_entry_t *me, rb_method_definition_t *def, void *opts);
+extern int rb_method_definition_eq(const rb_method_definition_t *d1, const rb_method_definition_t *d2);
 
 static const rb_iseq_t *
 def_iseq_ptr(rb_method_definition_t *def)
@@ -1590,7 +1597,7 @@ vm_call_iseq_setup_normal_0start(rb_execution_context_t *ec, rb_control_frame_t
     return vm_call_iseq_setup_normal(ec, cfp, calling, ci, cc, 0, param, local);
 }
 
-static inline int
+int
 simple_iseq_p(const rb_iseq_t *iseq)
 {
     return iseq->body->param.flags.has_opt == FALSE &&