lj_trace.c: Add penalty to trace abort message

(cherry picked from commit 47a7020)

lib/luajit/src/jit/dump.lua

@@ -550,7 +550,7 @@ local function fmterr(err, info)
 end
 
 -- Dump trace states.
-local function dump_trace(what, tr, func, pc, otr, oex)
+local function dump_trace(what, tr, func, pc, otr, oex, penalty)
   if what == "stop" or (what == "abort" and dumpmode.a) then
     if dumpmode.i then dump_ir(tr, dumpmode.s, dumpmode.r and what == "stop")
     elseif dumpmode.s then dump_snap(tr) end
@@ -565,7 +565,15 @@ local function dump_trace(what, tr, func, pc, otr, oex)
   elseif what == "stop" or what == "abort" then
     out:write("---- TRACE ", tr, " ", what)
     if what == "abort" then
-      out:write(" ", fmtfunc(func, pc), " -- ", fmterr(otr, oex), "\n")
+      out:write(" ", fmtfunc(func, pc), " -- ", fmterr(otr, oex))
+      if penalty then
+        if penalty == 0 then
+          out:write(" -- ", 'blacklisting')
+        else
+          out:write(" -- ", 'penalty '..penalty)
+        end
+        out:write("\n")
+      end
     else
       local info = traceinfo(tr)
       local link, ltype = info.link, info.linktype

lib/luajit/src/lj_trace.c

@@ -384,7 +384,7 @@ static void blacklist_pc(GCproto *pt, BCIns *pc)
 }
 
 /* Penalize a bytecode instruction. */
-static void penalty_pc(jit_State *J, GCproto *pt, BCIns *pc, TraceError e)
+static int penalty_pc(jit_State *J, GCproto *pt, BCIns *pc, TraceError e)
 {
   uint32_t i, val = PENALTY_MIN;
   for (i = 0; i < PENALTY_SLOTS; i++)
@@ -394,7 +394,7 @@ static void penalty_pc(jit_State *J, GCproto *pt, BCIns *pc, TraceError e)
 	    LJ_PRNG_BITS(J, PENALTY_RNDBITS);
       if (val > PENALTY_MAX) {
 	blacklist_pc(pt, pc);  /* Blacklist it, if that didn't help. */
-	return;
+	return(0);
       }
       goto setpenalty;
     }
@@ -406,6 +406,7 @@ static void penalty_pc(jit_State *J, GCproto *pt, BCIns *pc, TraceError e)
   J->penalty[i].val = val;
   J->penalty[i].reason = e;
   hotcount_set(J2GG(J), pc+1, val);
+  return(val);
 }
 
 /* -- Trace compiler state machine ---------------------------------------- */
@@ -570,6 +571,7 @@ static int trace_abort(jit_State *J)
   lua_State *L = J->L;
   TraceError e = LJ_TRERR_RECERR;
   TraceNo traceno;
+  int penalty = -1;
 
   J->postproc = LJ_POST_NONE;
   lj_mcode_abort(J);
@@ -591,7 +593,7 @@ static int trace_abort(jit_State *J)
       if (e == LJ_TRERR_RETRY)
 	hotcount_set(J2GG(J), startpc+1, 1);  /* Immediate retry. */
       else
-	penalty_pc(J, &gcref(J->cur.startpt)->pt, startpc, e);
+	penalty = penalty_pc(J, &gcref(J->cur.startpt)->pt, startpc, e);
     } else {
       traceref(J, J->exitno)->link = J->exitno;  /* Self-link is blacklisted. */
     }
@@ -621,6 +623,8 @@ static int trace_abort(jit_State *J)
       setintV(L->top++, proto_bcpos(funcproto(fn), pc));
       copyTV(L, L->top++, restorestack(L, errobj));
       copyTV(L, L->top++, &J->errinfo);
+      if (penalty >= 0)
+        setintV(L->top++, penalty);
     );
     /* Drop aborted trace after the vmevent (which may still access it). */
     setgcrefnull(J->trace[traceno]);