Add a "unknown callee" stat

Author: brandtbucher

Include/cpython/pystats.h

@@ -129,6 +129,7 @@ typedef struct _optimization_stats {
     uint64_t inner_loop;
     uint64_t recursive_call;
     uint64_t low_confidence;
+    uint64_t unknown_callee;
     uint64_t executors_invalidated;
     UOpStats opcode[PYSTATS_MAX_UOP_ID + 1];
     uint64_t unsupported_opcode[256];

Python/optimizer.c

@@ -757,7 +757,7 @@ translate_bytecode_to_trace(
                                 opcode == SEND_GEN)
                             {
                                 DPRINTF(2, "Bailing due to dynamic target\n");
-                                OPT_STAT_INC(low_confidence);
+                                OPT_STAT_INC(unknown_callee);
                                 return 0;
                             }
                             assert(_PyOpcode_Deopt[opcode] == CALL || _PyOpcode_Deopt[opcode] == CALL_KW);
@@ -824,7 +824,7 @@ translate_bytecode_to_trace(
                                 goto top;
                             }
                             DPRINTF(2, "Bail, new_code == NULL\n");
-                            OPT_STAT_INC(low_confidence);
+                            OPT_STAT_INC(unknown_callee);
                             return 0;
                         }
 

Python/specialize.c

@@ -260,6 +260,7 @@ print_optimization_stats(FILE *out, OptimizationStats *stats)
     fprintf(out, "Optimization inner loop: %" PRIu64 "\n", stats->inner_loop);
     fprintf(out, "Optimization recursive call: %" PRIu64 "\n", stats->recursive_call);
     fprintf(out, "Optimization low confidence: %" PRIu64 "\n", stats->low_confidence);
+    fprintf(out, "Optimization unknown callee: %" PRIu64 "\n", stats->unknown_callee);
     fprintf(out, "Executors invalidated: %" PRIu64 "\n", stats->executors_invalidated);
 
     print_histogram(out, "Trace length", stats->trace_length_hist);

Tools/scripts/summarize_stats.py

@@ -457,6 +457,7 @@ def get_optimization_stats(self) -> dict[str, tuple[int, int | None]]:
         inner_loop = self._data["Optimization inner loop"]
         recursive_call = self._data["Optimization recursive call"]
         low_confidence = self._data["Optimization low confidence"]
+        unknown_callee = self._data["Optimization unknown callee"]
         executors_invalidated = self._data["Executors invalidated"]
 
         return {
@@ -497,6 +498,10 @@ def get_optimization_stats(self) -> dict[str, tuple[int, int | None]]:
                 "A trace is abandoned because the likelihood of the jump to top being taken "
                 "is too low.",
             ): (low_confidence, attempts),
+            Doc(
+                "Unknown callee",
+                "A trace is abandoned because the target of a call is unknown.",
+            ): (unknown_callee, attempts),
             Doc(
                 "Executors invalidated",
                 "The number of executors that were invalidated due to watched "