[Tarantool-patches] [PATCH luajit] Show name of NYI bytecode in -jv and -jdump.

[Sergey Kaplun via Tarantool-patches <tarantool-patches@dev.tarantool.org>]

From: Mike Pall <mike>

Suggested by Sergey Kaplun.

(cherry picked from commit d2fe2a6d465a3e4c74c9876db94ae606f9c6983b)

This patch replaces the number of NYI bytecodes that can't be compiled
with their names in the `jit.dump()` and -jv outputs. Since the
functionality is the same, only `jit.dump()` is tested as most popular.

Sergey Kaplun:
* added the description and the test for the feature

Part of tarantool/tarantool#9924
---

Branch: https://github.com/tarantool/luajit/tree/skaplun/lj-567-1176-print-nyi-names
Related Issues:
* https://github.com/tarantool/tarantool/issues/9924
* https://github.com/LuaJIT/LuaJIT/pull/567
* https://github.com/LuaJIT/LuaJIT/issues/1176

 src/jit/dump.lua                              |  7 +-
 src/jit/v.lua                                 |  9 +-
 src/lj_traceerr.h                             |  2 +-
 .../lj-567-1176-print-nyi-names.test.lua      | 82 +++++++++++++++++++
 4 files changed, 96 insertions(+), 4 deletions(-)
 create mode 100644 test/tarantool-tests/lj-567-1176-print-nyi-names.test.lua

diff --git a/src/jit/dump.lua b/src/jit/dump.lua
index 84fe0044..e7f05253 100644
--- a/src/jit/dump.lua
+++ b/src/jit/dump.lua
@@ -543,7 +543,12 @@ local recdepth = 0
 local function fmterr(err, info)
   if type(err) == "number" then
     if type(info) == "function" then info = fmtfunc(info) end
-    err = format(vmdef.traceerr[err], info)
+    local fmt = vmdef.traceerr[err]
+    if fmt == "NYI: bytecode %s" then
+      local oidx = 6 * info
+      info = sub(vmdef.bcnames, oidx+1, oidx+6)
+    end
+    err = format(fmt, info)
   end
   return err
 end
diff --git a/src/jit/v.lua b/src/jit/v.lua
index 934de985..ff4e9c7c 100644
--- a/src/jit/v.lua
+++ b/src/jit/v.lua
@@ -63,7 +63,7 @@ assert(jit.version_num == 20100, "LuaJIT core/library version mismatch")
 local jutil = require("jit.util")
 local vmdef = require("jit.vmdef")
 local funcinfo, traceinfo = jutil.funcinfo, jutil.traceinfo
-local type, format = type, string.format
+local type, sub, format = type, string.sub, string.format
 local stdout, stderr = io.stdout, io.stderr
 
 -- Active flag and output file handle.
@@ -90,7 +90,12 @@ end
 local function fmterr(err, info)
   if type(err) == "number" then
     if type(info) == "function" then info = fmtfunc(info) end
-    err = format(vmdef.traceerr[err], info)
+    local fmt = vmdef.traceerr[err]
+    if fmt == "NYI: bytecode %s" then
+      local oidx = 6 * info
+      info = sub(vmdef.bcnames, oidx+1, oidx+6)
+    end
+    err = format(fmt, info)
   end
   return err
 end
diff --git a/src/lj_traceerr.h b/src/lj_traceerr.h
index 1363c4f3..beecbd8c 100644
--- a/src/lj_traceerr.h
+++ b/src/lj_traceerr.h
@@ -13,7 +13,7 @@ TREDEF(STACKOV,	"trace too deep")
 TREDEF(SNAPOV,	"too many snapshots")
 TREDEF(BLACKL,	"blacklisted")
 TREDEF(RETRY,	"retry recording")
-TREDEF(NYIBC,	"NYI: bytecode %d")
+TREDEF(NYIBC,	"NYI: bytecode %s")
 
 /* Recording loop ops. */
 TREDEF(LLEAVE,	"leaving loop in root trace")
diff --git a/test/tarantool-tests/lj-567-1176-print-nyi-names.test.lua b/test/tarantool-tests/lj-567-1176-print-nyi-names.test.lua
new file mode 100644
index 00000000..38829d2c
--- /dev/null
+++ b/test/tarantool-tests/lj-567-1176-print-nyi-names.test.lua
@@ -0,0 +1,82 @@
+local tap = require('tap')
+
+-- Test dumping of names of NYI bytecodes to be compiled instead
+-- of their numbers. See also:
+-- * https://github.com/LuaJIT/LuaJIT/pull/567,
+-- * https://github.com/LuaJIT/LuaJIT/issues/1176.
+
+local test = tap.test('lj-567-1176-print-nyi-names'):skipcond({
+  ['Test requires JIT enabled'] = not jit.status(),
+  ['Disabled on *BSD due to #4819'] = jit.os == 'BSD',
+})
+
+local jparse = require('utils').jit.parse
+
+test:plan(3)
+
+local function reset_jit()
+  -- Remove all previous traces.
+  jit.off()
+  jit.flush()
+  jit.on()
+  jit.opt.start('hotloop=1')
+end
+
+local function nop() end
+local function test_varg(...)
+  for _ = 1, 4 do nop(...) end
+end
+
+local function test_uv()
+  do
+    -- luacheck: ignore
+    local uclo
+    goto close_uv
+    local function _()
+      return uclo
+    end
+  end
+  ::close_uv::
+end
+
+-- We only need the abort reason in the test.
+jparse.start('t')
+reset_jit()
+
+test_varg()
+
+local _, aborted_traces = jparse.finish()
+assert(aborted_traces and aborted_traces[1],
+       'aborted trace with VARG is persisted')
+
+-- We tried to compile only one trace.
+local reason = aborted_traces[1][1].abort_reason
+test:like(reason, 'NYI: bytecode VARG', 'bytecode VARG name')
+
+jparse.start('t')
+reset_jit()
+
+for _ = 1, 4 do
+   local _ = function() end
+end
+_, aborted_traces = jparse.finish()
+assert(aborted_traces and aborted_traces[1],
+       'aborted trace with FNEW is persisted')
+
+reason = aborted_traces[1][1].abort_reason
+test:like(reason, 'NYI: bytecode FNEW', 'bytecode FNEW name')
+
+jparse.start('t')
+reset_jit()
+
+test_uv()
+test_uv()
+
+_, aborted_traces = jparse.finish()
+assert(aborted_traces and aborted_traces[1],
+       'aborted trace with UCLO is persisted')
+
+reason = aborted_traces[1][1].abort_reason
+test:like(reason, 'NYI: bytecode UCLO', 'bytecode UCLO name')
+
+test:done(true)
-- 
2.45.1