gh-126211: Exclude preprocessor directives from statements containing escaping calls (#126213)

The cases generator inserts code to save and restore the stack pointer around
statements that contain escaping calls. To find the beginning of such statements,
we would walk backwards from the escaping call until we encountered a token that
was treated as a statement terminator. This set of terminators should include
preprocessor directives.

Author: mpage

Lib/test/test_generated_cases.py

@@ -1429,6 +1429,39 @@ def test_instruction_size_macro(self):
         with self.assertRaisesRegex(SyntaxError, "All instructions containing a uop"):
             self.run_cases_test(input, output)
 
+    def test_escaping_call_next_to_cmacro(self):
+        input = """
+        inst(OP, (--)) {
+            #ifdef Py_GIL_DISABLED
+            escaping_call();
+            #else
+            another_escaping_call();
+            #endif
+            yet_another_escaping_call();
+        }
+        """
+        output = """
+        TARGET(OP) {
+            frame->instr_ptr = next_instr;
+            next_instr += 1;
+            INSTRUCTION_STATS(OP);
+            #ifdef Py_GIL_DISABLED
+            _PyFrame_SetStackPointer(frame, stack_pointer);
+            escaping_call();
+            stack_pointer = _PyFrame_GetStackPointer(frame);
+            #else
+            _PyFrame_SetStackPointer(frame, stack_pointer);
+            another_escaping_call();
+            stack_pointer = _PyFrame_GetStackPointer(frame);
+            #endif
+            _PyFrame_SetStackPointer(frame, stack_pointer);
+            yet_another_escaping_call();
+            stack_pointer = _PyFrame_GetStackPointer(frame);
+            DISPATCH();
+        }
+        """
+        self.run_cases_test(input, output)
+
 
 class TestGeneratedAbstractCases(unittest.TestCase):
     def setUp(self) -> None:

Tools/cases_generator/analyzer.py

@@ -637,7 +637,7 @@ def find_stmt_start(node: parser.InstDef, idx: int) -> lexer.Token:
     assert idx < len(node.block.tokens)
     while True:
         tkn = node.block.tokens[idx-1]
-        if tkn.kind in {"SEMI", "LBRACE", "RBRACE"}:
+        if tkn.kind in {"SEMI", "LBRACE", "RBRACE", "CMACRO"}:
             break
         idx -= 1
         assert idx > 0