From f49c778ffb78e5205a08e3777c61b7619b438e25 Mon Sep 17 00:00:00 2001
From: Guido van Rossum <guido@python.org>
Date: Tue, 7 Feb 2023 20:26:07 -0800
Subject: [PATCH] Remove support for legacy instructions

(A legacy instruction is of the form `instr(FOOBAR)`,
i.e. missing the `(... -- ...)` stack/cache effect annotation.)
---
 Tools/cases_generator/generate_cases.py |  4 +---
 Tools/cases_generator/parser.py         |  7 ++-----
 Tools/cases_generator/test_generator.py | 14 --------------
 3 files changed, 3 insertions(+), 22 deletions(-)

diff --git a/Tools/cases_generator/generate_cases.py b/Tools/cases_generator/generate_cases.py
index 49feb5048e59d8..d084faf48e1cc6 100644
--- a/Tools/cases_generator/generate_cases.py
+++ b/Tools/cases_generator/generate_cases.py
@@ -230,7 +230,7 @@ class Instruction:
 
     # Parts of the underlying instruction definition
     inst: parser.InstDef
-    kind: typing.Literal["inst", "op", "legacy"]  # Legacy means no (input -- output)
+    kind: typing.Literal["inst", "op"]
     name: str
     block: parser.Block
     block_text: list[str]  # Block.text, less curlies, less PREDICT() calls
@@ -904,8 +904,6 @@ def get_stack_effect_info(
         self, thing: parser.InstDef | parser.Super | parser.Macro | parser.Pseudo
     ) -> tuple[AnyInstruction | None, str, str]:
         def effect_str(effects: list[StackEffect]) -> str:
-            if getattr(thing, "kind", None) == "legacy":
-                return str(-1)
             n_effect, sym_effect = list_effect_size(effects)
             if sym_effect:
                 return f"{sym_effect} + {n_effect}" if n_effect else sym_effect
diff --git a/Tools/cases_generator/parser.py b/Tools/cases_generator/parser.py
index 56920f23d750c5..1ef7c36bf62c87 100644
--- a/Tools/cases_generator/parser.py
+++ b/Tools/cases_generator/parser.py
@@ -101,7 +101,7 @@ class OpName(Node):
 class InstHeader(Node):
     override: bool
     register: bool
-    kind: Literal["inst", "op", "legacy"]  # Legacy means no (inputs -- outputs)
+    kind: Literal["inst", "op"]
     name: str
     inputs: list[InputEffect]
     outputs: list[OutputEffect]
@@ -111,7 +111,7 @@ class InstHeader(Node):
 class InstDef(Node):
     override: bool
     register: bool
-    kind: Literal["inst", "op", "legacy"]
+    kind: Literal["inst", "op"]
     name: str
     inputs: list[InputEffect]
     outputs: list[OutputEffect]
@@ -182,9 +182,6 @@ def inst_header(self) -> InstHeader | None:
                     if self.expect(lx.RPAREN):
                         if (tkn := self.peek()) and tkn.kind == lx.LBRACE:
                             return InstHeader(override, register, kind, name, inp, outp)
-                elif self.expect(lx.RPAREN) and kind == "inst":
-                    # No legacy stack effect if kind is "op".
-                    return InstHeader(override, register, "legacy", name, [], [])
         return None
 
     def io_effect(self) -> tuple[list[InputEffect], list[OutputEffect]]:
diff --git a/Tools/cases_generator/test_generator.py b/Tools/cases_generator/test_generator.py
index 036094ac8ef487..412d3d14590050 100644
--- a/Tools/cases_generator/test_generator.py
+++ b/Tools/cases_generator/test_generator.py
@@ -62,20 +62,6 @@ def run_cases_test(input: str, expected: str):
     #     print("End")
     assert actual.rstrip() == expected.rstrip()
 
-def test_legacy():
-    input = """
-        inst(OP) {
-            spam();
-        }
-    """
-    output = """
-        TARGET(OP) {
-            spam();
-            DISPATCH();
-        }
-    """
-    run_cases_test(input, output)
-
 def test_inst_no_args():
     input = """
         inst(OP, (--)) {