Push fix noticed by Mark and Brandt

Author: Fidget-Spinner

Include/internal/pycore_optimizer.h

@@ -260,6 +260,7 @@ typedef struct _JitOptContext {
 extern bool _Py_uop_sym_is_null(JitOptSymbol *sym);
 extern bool _Py_uop_sym_is_not_null(JitOptSymbol *sym);
 extern bool _Py_uop_sym_is_const(JitOptContext *ctx, JitOptSymbol *sym);
+extern bool _Py_uop_sym_is_safe_const(JitOptContext *ctx, JitOptSymbol *sym);
 extern PyObject *_Py_uop_sym_get_const(JitOptContext *ctx, JitOptSymbol *sym);
 extern JitOptSymbol *_Py_uop_sym_new_const_steal(JitOptContext *ctx, PyObject *const_val);
 extern _PyStackRef _Py_uop_sym_get_const_as_stackref(JitOptContext *ctx, JitOptSymbol *sym);

Lib/test/test_generated_cases.py

@@ -2270,7 +2270,7 @@ def test_pure_uop_body_copied_in(self):
             JitOptSymbol *res;
             foo = stack_pointer[-1];
             if (
-                sym_is_const(ctx, foo)
+                sym_is_safe_const(ctx, foo)
             ) {
                 JitOptSymbol *foo_sym = foo;
                 _PyStackRef foo = sym_get_const_as_stackref(ctx, foo_sym);
@@ -2312,7 +2312,7 @@ def test_pure_uop_body_copied_in_complex(self):
             JitOptSymbol *res;
             foo = stack_pointer[-1];
             if (
-                sym_is_const(ctx, foo)
+                sym_is_safe_const(ctx, foo)
             ) {
                 JitOptSymbol *foo_sym = foo;
                 _PyStackRef foo = sym_get_const_as_stackref(ctx, foo_sym);

Python/optimizer_analysis.c

@@ -319,6 +319,7 @@ remove_globals(_PyInterpreterFrame *frame, _PyUOpInstruction *buffer,
 /* Shortened forms for convenience, used in optimizer_bytecodes.c */
 #define sym_is_not_null _Py_uop_sym_is_not_null
 #define sym_is_const _Py_uop_sym_is_const
+#define sym_is_safe_const _Py_uop_sym_is_safe_const
 #define sym_get_const _Py_uop_sym_get_const
 #define sym_new_const_steal _Py_uop_sym_new_const_steal
 #define sym_get_const_as_stackref _Py_uop_sym_get_const_as_stackref

Python/optimizer_cases.c.h

@@ -159,6 +159,26 @@ _Py_uop_sym_get_const_as_stackref(JitOptContext *ctx, JitOptSymbol *sym)
     return PyStackRef_FromPyObjectImmortalUnchecked(const_val);
 }
 
+/*
+ Indicates whether the constant is safe to constant evaluate
+ (without side effects).
+ */
+bool
+_Py_uop_sym_is_safe_const(JitOptContext *ctx, JitOptSymbol *sym)
+{
+    PyObject *const_val = _Py_uop_sym_get_const(ctx, sym);
+    if (const_val == NULL) {
+        return false;
+    }
+    PyTypeObject *typ = Py_TYPE(const_val);
+    return (typ == &PyLong_Type) ||
+        (typ == &PyUnicode_Type) ||
+        (typ == &PyFloat_Type) ||
+        (typ == &PyDict_Type) ||
+        (typ == &PyTuple_Type) ||
+        (typ == &PyList_Type);
+}
+
 void
 _Py_uop_sym_set_type(JitOptContext *ctx, JitOptSymbol *sym, PyTypeObject *typ)
 {

Python/optimizer_symbols.c

@@ -187,8 +187,8 @@ def write_uop_pure_evaluation_region_header(
     emitter.emit("if (\n")
     assert len(uop.stack.inputs) > 0, "Pure operations must have at least 1 input"
     for inp in uop.stack.inputs[:-1]:
-        emitter.emit(f"sym_is_const(ctx, {inp.name}) &&\n")
-    emitter.emit(f"sym_is_const(ctx, {uop.stack.inputs[-1].name})\n")
+        emitter.emit(f"sym_is_safe_const(ctx, {inp.name}) &&\n")
+    emitter.emit(f"sym_is_safe_const(ctx, {uop.stack.inputs[-1].name})\n")
     emitter.emit(') {\n')
     # Declare variables, before they are shadowed.
     for inp in uop.stack.inputs: