Remove Reverse bytecode (RustPython#6675)

ShaharNaveh · youknowone · github-actions[bot] · web-flow · commit 6fe05987f0b4 · 2026-01-10T18:55:15.000+09:00
* Remove `Reverse` bytecode

* Update crates/compiler-core/src/bytecode.rs

Co-authored-by: Jeong, YunWon &lt;69878+youknowone@users.noreply.github.com&gt;

* Gen

* Remove Reverse

* Auto-format: cargo fmt --all

* Revert comment

* Remove debug code

* Fix CI

---------

Co-authored-by: Jeong, YunWon &lt;69878+youknowone@users.noreply.github.com&gt;
Co-authored-by: github-actions[bot] &lt;github-actions[bot]@users.noreply.github.com&gt;
diff --git a/.github/workflows/ci.yaml b/.github/workflows/ci.yaml
@@ -334,7 +334,7 @@ jobs:
       - name: Ensure Lib/_opcode_metadata is updated
         run: |
           python scripts/generate_opcode_metadata.py
-          if [ -z "$(git status --porcelain)" ]; then
+          if [ -n "$(git status --porcelain)" ]; then
             exit 1
           fi
 
diff --git a/Lib/_opcode_metadata.py b/Lib/_opcode_metadata.py
@@ -4,10 +4,6 @@
 
 _specializations = {}
 
-
-
-
-
 _specialized_opmap = {}
 
 opmap = {
@@ -141,7 +137,6 @@
     'JUMP_IF_TRUE_OR_POP': 130,
     'JUMP_IF_NOT_EXC_MATCH': 131,
     'LOAD_CLASS_DEREF': 132,
-    'REVERSE': 133,
     'SET_EXC_INFO': 134,
     'SUBSCRIPT': 135,
     'RESUME': 149,
diff --git a/crates/compiler-core/src/bytecode.rs b/crates/compiler-core/src/bytecode.rs
@@ -932,9 +932,6 @@ pub enum Instruction {
     } = 130,
     JumpIfNotExcMatch(Arg<Label>) = 131,
     LoadClassDeref(Arg<NameIdx>) = 132,
-    Reverse {
-        amount: Arg<u32>,
-    } = 133,
     SetExcInfo = 134,
     Subscript = 135,
     // ===== Pseudo Opcodes (252+) ======
@@ -1000,9 +997,6 @@ impl TryFrom<u8> for Instruction {
             }),
             u8::from(Self::JumpIfNotExcMatch(Arg::marker())),
             u8::from(Self::LoadClassDeref(Arg::marker())),
-            u8::from(Self::Reverse {
-                amount: Arg::marker(),
-            }),
             u8::from(Self::SetExcInfo),
             u8::from(Self::Subscript),
         ];
@@ -1922,7 +1916,6 @@ impl Instruction {
                 -1 + before as i32 + 1 + after as i32
             }
             PopExcept => 0,
-            Reverse { .. } => 0,
             GetAwaitable => 0,
             BeforeAsyncWith => 1,
             GetAIter => 0,
@@ -2094,7 +2087,6 @@ impl Instruction {
             Resume { arg } => w!(RESUME, arg),
             ReturnConst { idx } => fmt_const("RETURN_CONST", arg, f, idx),
             ReturnValue => w!(RETURN_VALUE),
-            Reverse { amount } => w!(REVERSE, amount),
             Send { target } => w!(SEND, target),
             SetAdd { i } => w!(SET_ADD, i),
             SetExcInfo => w!(SET_EXC_INFO),
diff --git a/crates/vm/src/frame.rs b/crates/vm/src/frame.rs
@@ -1458,11 +1458,6 @@ impl ExecutingFrame<'_> {
                 let value = self.pop_value();
                 self.unwind_blocks(vm, UnwindReason::Returning { value })
             }
-            bytecode::Instruction::Reverse { amount } => {
-                let stack_len = self.state.stack.len();
-                self.state.stack[stack_len - amount.get(arg) as usize..stack_len].reverse();
-                Ok(None)
-            }
             bytecode::Instruction::SetAdd { i } => {
                 let item = self.pop_value();
                 let obj = self.nth_value(i.get(arg));
diff --git a/scripts/generate_opcode_metadata.py b/scripts/generate_opcode_metadata.py
@@ -25,8 +25,6 @@ def cpython_name(self) -> str:
         name = self.rust_name
         name = re.sub(r"(?<=[a-z0-9])([A-Z])", r"_\1", name)
         return re.sub(r"(\D)(\d+)$", r"\1_\2", name).upper()
-        return re.sub(r"(?<=[a-z0-9])([A-Z])", r"_\1", self.rust_name).upper()
-        return re.sub(r"(?<!^)(?=[A-Z])", "_", self.rust_name).upper()
 
     @classmethod
     def from_str(cls, body: str):
