GH-116017: Get rid of _COLD_EXITs (GH-120960)

Author: brandtbucher

Include/internal/pycore_backoff.h

@@ -122,14 +122,14 @@ initial_jump_backoff_counter(void)
  * otherwise when a side exit warms up we may construct
  * a new trace before the Tier 1 code has properly re-specialized.
  * Backoff sequence 64, 128, 256, 512, 1024, 2048, 4096. */
-#define COLD_EXIT_INITIAL_VALUE 64
-#define COLD_EXIT_INITIAL_BACKOFF 6
+#define SIDE_EXIT_INITIAL_VALUE 64
+#define SIDE_EXIT_INITIAL_BACKOFF 6
 
 static inline _Py_BackoffCounter
 initial_temperature_backoff_counter(void)
 {
-    return make_backoff_counter(COLD_EXIT_INITIAL_VALUE,
-                                COLD_EXIT_INITIAL_BACKOFF);
+    return make_backoff_counter(SIDE_EXIT_INITIAL_VALUE,
+                                SIDE_EXIT_INITIAL_BACKOFF);
 }
 
 /* Unreachable backoff counter. */

Include/internal/pycore_code.h

@@ -535,7 +535,7 @@ write_location_entry_start(uint8_t *ptr, int code, int length)
 #define ADAPTIVE_COOLDOWN_BACKOFF 0
 
 // Can't assert this in pycore_backoff.h because of header order dependencies
-static_assert(COLD_EXIT_INITIAL_VALUE > ADAPTIVE_COOLDOWN_VALUE,
+static_assert(SIDE_EXIT_INITIAL_VALUE > ADAPTIVE_COOLDOWN_VALUE,
     "Cold exit value should be larger than adaptive cooldown value");
 
 static inline _Py_BackoffCounter

Include/internal/pycore_optimizer.h

@@ -41,24 +41,18 @@ typedef struct {
  * the 32 bits between the oparg and operand are:
  * UOP_FORMAT_TARGET:
  *    uint32_t target;
- * UOP_FORMAT_EXIT
- *    uint16_t exit_index;
- *    uint16_t error_target;
  * UOP_FORMAT_JUMP
  *    uint16_t jump_target;
  *    uint16_t error_target;
  */
 typedef struct {
-    uint16_t opcode:14;
-    uint16_t format:2;
+    uint16_t opcode:15;
+    uint16_t format:1;
     uint16_t oparg;
     union {
         uint32_t target;
         struct {
-            union {
-                uint16_t exit_index;
-                uint16_t jump_target;
-            };
+            uint16_t jump_target;
             uint16_t error_target;
         };
     };
@@ -160,22 +154,14 @@ struct _Py_UopsSymbol {
 };
 
 #define UOP_FORMAT_TARGET 0
-#define UOP_FORMAT_EXIT 1
-#define UOP_FORMAT_JUMP 2
-#define UOP_FORMAT_UNUSED 3
+#define UOP_FORMAT_JUMP 1
 
 static inline uint32_t uop_get_target(const _PyUOpInstruction *inst)
 {
     assert(inst->format == UOP_FORMAT_TARGET);
     return inst->target;
 }
 
-static inline uint16_t uop_get_exit_index(const _PyUOpInstruction *inst)
-{
-    assert(inst->format == UOP_FORMAT_EXIT);
-    return inst->exit_index;
-}
-
 static inline uint16_t uop_get_jump_target(const _PyUOpInstruction *inst)
 {
     assert(inst->format == UOP_FORMAT_JUMP);