GH-106008: Make implicit boolean conversions explicit (GH-106003)

Author: brandtbucher

.gitattributes

@@ -85,8 +85,9 @@ Parser/parser.c                                     generated
 Parser/token.c                                      generated
 Programs/test_frozenmain.h                          generated
 Python/Python-ast.c                                 generated
-Python/generated_cases.c.h                          generated
 Python/executor_cases.c.h                           generated
+Python/generated_cases.c.h                          generated
+Python/opcode_metadata.h                            generated
 Python/opcode_targets.h                             generated
 Python/stdlib_module_names.h                        generated
 Tools/peg_generator/pegen/grammar_parser.py         generated

Doc/library/dis.rst

@@ -529,6 +529,9 @@ result back on the stack.
 
    Implements ``STACK[-1] = not STACK[-1]``.
 
+   .. versionchanged:: 3.13
+      This instruction now requires an exact :class:`bool` operand.
+
 
 .. opcode:: UNARY_INVERT
 
@@ -548,6 +551,13 @@ result back on the stack.
    .. versionadded:: 3.5
 
 
+.. opcode:: TO_BOOL
+
+   Implements ``STACK[-1] = bool(STACK[-1])``.
+
+   .. versionadded:: 3.13
+
+
 **Binary and in-place operations**
 
 Binary operations remove the top two items from the stack (``STACK[-1]`` and
@@ -1127,7 +1137,12 @@ iterations of the loop.
 .. opcode:: COMPARE_OP (opname)
 
    Performs a Boolean operation.  The operation name can be found in
-   ``cmp_op[opname]``.
+   ``cmp_op[opname >> 5]``. If the fifth-lowest bit of ``opname`` is set
+   (``opname & 16``), the result should be coerced to ``bool``.
+
+   .. versionchanged:: 3.13
+      The fifth-lowest bit of the oparg now indicates a forced conversion to
+      :class:`bool`.
 
 
 .. opcode:: IS_OP (invert)
@@ -1191,6 +1206,9 @@ iterations of the loop.
    .. versionchanged:: 3.12
       This is no longer a pseudo-instruction.
 
+   .. versionchanged:: 3.13
+      This instruction now requires an exact :class:`bool` operand.
+
 .. opcode:: POP_JUMP_IF_FALSE (delta)
 
    If ``STACK[-1]`` is false, increments the bytecode counter by *delta*.
@@ -1204,6 +1222,9 @@ iterations of the loop.
    .. versionchanged:: 3.12
       This is no longer a pseudo-instruction.
 
+   .. versionchanged:: 3.13
+      This instruction now requires an exact :class:`bool` operand.
+
 .. opcode:: POP_JUMP_IF_NOT_NONE (delta)
 
    If ``STACK[-1]`` is not ``None``, increments the bytecode counter by *delta*.

Include/internal/pycore_code.h

@@ -101,6 +101,13 @@ typedef struct {
 
 #define INLINE_CACHE_ENTRIES_SEND CACHE_ENTRIES(_PySendCache)
 
+typedef struct {
+    uint16_t counter;
+    uint16_t version[2];
+} _PyToBoolCache;
+
+#define INLINE_CACHE_ENTRIES_TO_BOOL CACHE_ENTRIES(_PyToBoolCache)
+
 // Borrowed references to common callables:
 struct callable_cache {
     PyObject *isinstance;
@@ -246,6 +253,7 @@ extern void _Py_Specialize_UnpackSequence(PyObject *seq, _Py_CODEUNIT *instr,
                                           int oparg);
 extern void _Py_Specialize_ForIter(PyObject *iter, _Py_CODEUNIT *instr, int oparg);
 extern void _Py_Specialize_Send(PyObject *receiver, _Py_CODEUNIT *instr);
+extern void _Py_Specialize_ToBool(PyObject *value, _Py_CODEUNIT *instr);
 
 /* Finalizer function for static codeobjects used in deepfreeze.py */
 extern void _PyStaticCode_Fini(PyCodeObject *co);