gh-106529: Implement POP_JUMP_IF_XXX uops (#106551)

- Hand-written uops JUMP_IF_{TRUE,FALSE}.
  These peek at the top of the stack.
  The jump target (in superblock space) is absolute.

- Hand-written translation for POP_JUMP_IF_{TRUE,FALSE},
  assuming the jump is unlikely.
  Once we implement jump-likelihood profiling,
  we can implement the jump-unlikely case (in another PR).

- Tests (including some test cleanup).

- Improvements to len(ex) and ex[i] to expose the whole trace.

1 files changed, 21 insertions, 1 deletions

diff --git a/Python/ceval.c b/Python/ceval.c
index da11355..866acd2 100644
--- a/Python/ceval.c
+++ b/Python/ceval.c
@@ -2751,7 +2751,8 @@ _PyUopExecute(_PyExecutorObject *executor, _PyInterpreterFrame *frame, PyObject
         operand = self->trace[pc].operand;
         oparg = (int)operand;
         DPRINTF(3,
-                "  uop %s, operand %" PRIu64 ", stack_level %d\n",
+                "%4d: uop %s, operand %" PRIu64 ", stack_level %d\n",
+                pc,
                 opcode < 256 ? _PyOpcode_OpName[opcode] : _PyOpcode_uop_name[opcode],
                 operand,
                 (int)(stack_pointer - _PyFrame_Stackbase(frame)));
@@ -2763,6 +2764,25 @@ _PyUopExecute(_PyExecutorObject *executor, _PyInterpreterFrame *frame, PyObject
 #define ENABLE_SPECIALIZATION 0
 #include "executor_cases.c.h"
 
+            // NOTE: These pop-jumps move the uop pc, not the bytecode ip
+            case _POP_JUMP_IF_FALSE:
+            {
+                if (Py_IsFalse(stack_pointer[-1])) {
+                    pc = oparg;
+                }
+                stack_pointer--;
+                break;
+            }
+
+            case _POP_JUMP_IF_TRUE:
+            {
+                if (Py_IsTrue(stack_pointer[-1])) {
+                    pc = oparg;
+                }
+                stack_pointer--;
+                break;
+            }
+
             case SAVE_IP:
             {
                 frame->prev_instr = ip_offset + oparg;