From 91f5965a257a34d88cf73e5d27a2ca8564009f74 Mon Sep 17 00:00:00 2001
From: ShaharNaveh <50263213+ShaharNaveh@users.noreply.github.com>
Date: Fri, 28 Nov 2025 21:51:32 +0200
Subject: [PATCH 1/3] Split `TestOperator` inatruction

---
 crates/codegen/src/compile.rs        | 48 ++++-------------
 crates/compiler-core/src/bytecode.rs | 53 ++++++++++--------
 crates/vm/src/frame.rs               | 81 ++++++++++++++++------------
 3 files changed, 88 insertions(+), 94 deletions(-)

diff --git a/crates/codegen/src/compile.rs b/crates/codegen/src/compile.rs
index b2dc10cda6c..4a4f17edcfa 100644
--- a/crates/codegen/src/compile.rs
+++ b/crates/codegen/src/compile.rs
@@ -36,7 +36,7 @@ use rustpython_compiler_core::{
     Mode, OneIndexed, PositionEncoding, SourceFile, SourceLocation,
     bytecode::{
         self, Arg as OpArgMarker, BinaryOperator, CodeObject, ComparisonOperator, ConstantData,
-        Instruction, OpArg, OpArgType, UnpackExArgs,
+        Instruction, Invert, OpArg, OpArgType, UnpackExArgs,
     },
 };
 use rustpython_wtf8::Wtf8Buf;
@@ -2034,20 +2034,7 @@ impl Compiler {
 
                 // Check exception type:
                 self.compile_expression(exc_type)?;
-                emit!(
-                    self,
-                    Instruction::TestOperation {
-                        op: bytecode::TestOperator::ExceptionMatch,
-                    }
-                );
-
-                // We cannot handle this exception type:
-                emit!(
-                    self,
-                    Instruction::PopJumpIfFalse {
-                        target: next_handler,
-                    }
-                );
+                emit!(self, Instruction::JumpIfNotExcMatch(next_handler));
 
                 // We have a match, store in name (except x as y)
                 if let Some(alias) = name {
@@ -3477,12 +3464,7 @@ impl Compiler {
         // 4. Load None.
         self.emit_load_const(ConstantData::None);
         // 5. Compare with IS_OP 1.
-        emit!(
-            self,
-            Instruction::TestOperation {
-                op: bytecode::TestOperator::IsNot
-            }
-        );
+        emit!(self, Instruction::IsOp(Invert::Yes));
 
         // At this point the TOS is a tuple of (nargs + n_attrs) attributes (or None).
         pc.on_top += 1;
@@ -3648,12 +3630,8 @@ impl Compiler {
 
         // Check if copy is None (consumes the copy like POP_JUMP_IF_NONE)
         self.emit_load_const(ConstantData::None);
-        emit!(
-            self,
-            Instruction::TestOperation {
-                op: bytecode::TestOperator::IsNot
-            }
-        );
+        emit!(self, Instruction::IsOp(Invert::Yes));
+
         // Stack: [subject, keys_tuple, values_tuple, bool]
         self.jump_to_fail_pop(pc, JumpOp::PopJumpIfFalse)?;
         // Stack: [subject, keys_tuple, values_tuple]
@@ -3948,12 +3926,7 @@ impl Compiler {
             Singleton::True => ConstantData::Boolean { value: true },
         });
         // Compare using the "Is" operator.
-        emit!(
-            self,
-            Instruction::TestOperation {
-                op: bytecode::TestOperator::Is
-            }
-        );
+        emit!(self, Instruction::IsOp(Invert::No));
         // Jump to the failure label if the comparison is false.
         self.jump_to_fail_pop(pc, JumpOp::PopJumpIfFalse)?;
         Ok(())
@@ -4082,7 +4055,6 @@ impl Compiler {
         let (last_val, mid_exprs) = exprs.split_last().unwrap();
 
         use bytecode::ComparisonOperator::*;
-        use bytecode::TestOperator::*;
         let compile_cmpop = |c: &mut Self, op: &CmpOp| match op {
             CmpOp::Eq => emit!(c, Instruction::CompareOperation { op: Equal }),
             CmpOp::NotEq => emit!(c, Instruction::CompareOperation { op: NotEqual }),
@@ -4092,10 +4064,10 @@ impl Compiler {
             CmpOp::GtE => {
                 emit!(c, Instruction::CompareOperation { op: GreaterOrEqual })
             }
-            CmpOp::In => emit!(c, Instruction::TestOperation { op: In }),
-            CmpOp::NotIn => emit!(c, Instruction::TestOperation { op: NotIn }),
-            CmpOp::Is => emit!(c, Instruction::TestOperation { op: Is }),
-            CmpOp::IsNot => emit!(c, Instruction::TestOperation { op: IsNot }),
+            CmpOp::In => emit!(c, Instruction::ContainsOp(Invert::No)),
+            CmpOp::NotIn => emit!(c, Instruction::ContainsOp(Invert::Yes)),
+            CmpOp::Is => emit!(c, Instruction::IsOp(Invert::No)),
+            CmpOp::IsNot => emit!(c, Instruction::IsOp(Invert::Yes)),
         };
 
         // a == b == c == d
diff --git a/crates/compiler-core/src/bytecode.rs b/crates/compiler-core/src/bytecode.rs
index fe28517cda8..d7780bfd7b8 100644
--- a/crates/compiler-core/src/bytecode.rs
+++ b/crates/compiler-core/src/bytecode.rs
@@ -577,6 +577,10 @@ pub enum Instruction {
     Subscript,
     StoreSubscript,
     DeleteSubscript,
+    /// Performs `is` comparison, or `is not` if `invert` is 1.
+    IsOp(Arg<Invert>),
+    /// Performs `in` comparison, or `not in` if `invert` is 1.
+    ContainsOp(Arg<Invert>),
     StoreAttr {
         idx: Arg<NameIdx>,
     },
@@ -600,9 +604,6 @@ pub enum Instruction {
     LoadAttr {
         idx: Arg<NameIdx>,
     },
-    TestOperation {
-        op: Arg<TestOperator>,
-    },
     CompareOperation {
         op: Arg<ComparisonOperator>,
     },
@@ -628,6 +629,10 @@ pub enum Instruction {
     Break {
         target: Arg<Label>,
     },
+    /// Performs exception matching for except.
+    /// Tests whether the STACK[-2] is an exception matching STACK[-1].
+    /// Pops STACK[-1] and pushes the boolean result of the test.
+    JumpIfNotExcMatch(Arg<Label>),
     Jump {
         target: Arg<Label>,
     },
@@ -1088,19 +1093,6 @@ op_arg_enum!(
     }
 );
 
-op_arg_enum!(
-    #[derive(Debug, Copy, Clone, PartialEq, Eq)]
-    #[repr(u8)]
-    pub enum TestOperator {
-        In = 0,
-        NotIn = 1,
-        Is = 2,
-        IsNot = 3,
-        /// two exceptions that match?
-        ExceptionMatch = 4,
-    }
-);
-
 op_arg_enum!(
     /// The possible Binary operators
     /// # Examples
@@ -1141,6 +1133,24 @@ op_arg_enum!(
     }
 );
 
+op_arg_enum!(
+    /// Whether or not to invert the operation.
+    #[repr(u8)]
+    #[derive(Debug, Copy, Clone, PartialEq, Eq)]
+    pub enum Invert {
+        /// ```py
+        /// foo is bar
+        /// x in lst
+        /// ```
+        No = 0,
+        /// ```py
+        /// foo is not bar
+        /// x not in lst
+        /// ```
+        Yes = 1,
+    }
+);
+
 #[derive(Copy, Clone)]
 pub struct UnpackExArgs {
     pub before: u8,
@@ -1462,10 +1472,7 @@ impl Instruction {
             DeleteAttr { .. } => -1,
             LoadConst { .. } => 1,
             UnaryOperation { .. } => 0,
-            BinaryOperation { .. }
-            | BinaryOperationInplace { .. }
-            | TestOperation { .. }
-            | CompareOperation { .. } => -1,
+            BinaryOperation { .. } | BinaryOperationInplace { .. } | CompareOperation { .. } => -1,
             BinarySubscript => -1,
             CopyItem { .. } => 1,
             Pop => -1,
@@ -1508,6 +1515,8 @@ impl Instruction {
                     1
                 }
             }
+            IsOp(_) | ContainsOp(_) => -1,
+            JumpIfNotExcMatch(_) => -2,
             ReturnValue => -1,
             ReturnConst { .. } => 0,
             Resume { .. } => 0,
@@ -1654,6 +1663,9 @@ impl Instruction {
             DeleteGlobal(idx) => w!(DeleteGlobal, name = idx),
             DeleteDeref(idx) => w!(DeleteDeref, cell_name = idx),
             LoadClosure(i) => w!(LoadClosure, cell_name = i),
+            IsOp(inv) => w!(IS_OP, ?inv),
+            ContainsOp(inv) => w!(CONTAINS_OP, ?inv),
+            JumpIfNotExcMatch(target) => w!(JUMP_IF_NOT_EXC_MATCH, target),
             Subscript => w!(Subscript),
             StoreSubscript => w!(StoreSubscript),
             DeleteSubscript => w!(DeleteSubscript),
@@ -1665,7 +1677,6 @@ impl Instruction {
             BinaryOperationInplace { op } => w!(BinaryOperationInplace, ?op),
             BinarySubscript => w!(BinarySubscript),
             LoadAttr { idx } => w!(LoadAttr, name = idx),
-            TestOperation { op } => w!(TestOperation, ?op),
             CompareOperation { op } => w!(CompareOperation, ?op),
             CopyItem { index } => w!(CopyItem, index),
             Pop => w!(Pop),
diff --git a/crates/vm/src/frame.rs b/crates/vm/src/frame.rs
index 8deaada0827..148abacf6ad 100644
--- a/crates/vm/src/frame.rs
+++ b/crates/vm/src/frame.rs
@@ -884,7 +884,52 @@ impl ExecutingFrame<'_> {
             bytecode::Instruction::StoreAttr { idx } => self.store_attr(vm, idx.get(arg)),
             bytecode::Instruction::DeleteAttr { idx } => self.delete_attr(vm, idx.get(arg)),
             bytecode::Instruction::UnaryOperation { op } => self.execute_unary_op(vm, op.get(arg)),
-            bytecode::Instruction::TestOperation { op } => self.execute_test(vm, op.get(arg)),
+            bytecode::Instruction::IsOp(invert) => {
+                let b = self.pop_value();
+                let a = self.pop_value();
+                let res = a.is(&b);
+
+                let value = match invert.get(arg) {
+                    bytecode::Invert::No => res,
+                    bytecode::Invert::Yes => !res,
+                };
+                self.push_value(vm.ctx.new_bool(value).into());
+                Ok(None)
+            }
+            bytecode::Instruction::ContainsOp(invert) => {
+                let b = self.pop_value();
+                let a = self.pop_value();
+
+                let value = match invert.get(arg) {
+                    bytecode::Invert::No => self._in(vm, &a, &b)?,
+                    bytecode::Invert::Yes => self._not_in(vm, &a, &b)?,
+                };
+                self.push_value(vm.ctx.new_bool(value).into());
+                Ok(None)
+            }
+            bytecode::Instruction::JumpIfNotExcMatch(target) => {
+                let b = self.pop_value();
+                let a = self.pop_value();
+                if let Some(tuple_of_exceptions) = b.downcast_ref::<PyTuple>() {
+                    for exception in tuple_of_exceptions {
+                        if !exception
+                            .is_subclass(vm.ctx.exceptions.base_exception_type.into(), vm)?
+                        {
+                            return Err(vm.new_type_error(
+                                "catching classes that do not inherit from BaseException is not allowed",
+                            ));
+                        }
+                    }
+                } else if !b.is_subclass(vm.ctx.exceptions.base_exception_type.into(), vm)? {
+                    return Err(vm.new_type_error(
+                        "catching classes that do not inherit from BaseException is not allowed",
+                    ));
+                }
+
+                let value = a.is_instance(&b, vm)?;
+                self.push_value(vm.ctx.new_bool(value).into());
+                self.pop_jump_if(vm, target.get(arg), false)
+            }
             bytecode::Instruction::CompareOperation { op } => self.execute_compare(vm, op.get(arg)),
             bytecode::Instruction::ReturnValue => {
                 let value = self.pop_value();
@@ -2234,40 +2279,6 @@ impl ExecutingFrame<'_> {
         Ok(!self._in(vm, needle, haystack)?)
     }
 
-    #[cfg_attr(feature = "flame-it", flame("Frame"))]
-    fn execute_test(&mut self, vm: &VirtualMachine, op: bytecode::TestOperator) -> FrameResult {
-        let b = self.pop_value();
-        let a = self.pop_value();
-        let value = match op {
-            bytecode::TestOperator::Is => a.is(&b),
-            bytecode::TestOperator::IsNot => !a.is(&b),
-            bytecode::TestOperator::In => self._in(vm, &a, &b)?,
-            bytecode::TestOperator::NotIn => self._not_in(vm, &a, &b)?,
-            bytecode::TestOperator::ExceptionMatch => {
-                if let Some(tuple_of_exceptions) = b.downcast_ref::<PyTuple>() {
-                    for exception in tuple_of_exceptions {
-                        if !exception
-                            .is_subclass(vm.ctx.exceptions.base_exception_type.into(), vm)?
-                        {
-                            return Err(vm.new_type_error(
-                                "catching classes that do not inherit from BaseException is not allowed",
-                            ));
-                        }
-                    }
-                } else if !b.is_subclass(vm.ctx.exceptions.base_exception_type.into(), vm)? {
-                    return Err(vm.new_type_error(
-                        "catching classes that do not inherit from BaseException is not allowed",
-                    ));
-                }
-
-                a.is_instance(&b, vm)?
-            }
-        };
-
-        self.push_value(vm.ctx.new_bool(value).into());
-        Ok(None)
-    }
-
     #[cfg_attr(feature = "flame-it", flame("Frame"))]
     fn execute_compare(
         &mut self,

From 625480d8b110828c4391c979b2aee32c38fe13b2 Mon Sep 17 00:00:00 2001
From: ShaharNaveh <50263213+ShaharNaveh@users.noreply.github.com>
Date: Fri, 28 Nov 2025 22:52:35 +0200
Subject: [PATCH 2/3] Update snapshot

---
 ...pile__tests__nested_double_async_with.snap | 69 +++++++++----------
 1 file changed, 34 insertions(+), 35 deletions(-)

diff --git a/crates/codegen/src/snapshots/rustpython_codegen__compile__tests__nested_double_async_with.snap b/crates/codegen/src/snapshots/rustpython_codegen__compile__tests__nested_double_async_with.snap
index dc624c7b6a1..d34398cb3b1 100644
--- a/crates/codegen/src/snapshots/rustpython_codegen__compile__tests__nested_double_async_with.snap
+++ b/crates/codegen/src/snapshots/rustpython_codegen__compile__tests__nested_double_async_with.snap
@@ -1,5 +1,5 @@
 ---
-source: compiler/codegen/src/compile.rs
+source: crates/codegen/src/compile.rs
 expression: "compile_exec(\"\\\nfor stop_exc in (StopIteration('spam'), StopAsyncIteration('ham')):\n    with self.subTest(type=type(stop_exc)):\n        try:\n            async with egg():\n                raise stop_exc\n        except Exception as ex:\n            self.assertIs(ex, stop_exc)\n        else:\n            self.fail(f'{stop_exc} was suppressed')\n\")"
 ---
   1           0 SetupLoop
@@ -11,7 +11,7 @@ expression: "compile_exec(\"\\\nfor stop_exc in (StopIteration('spam'), StopAsyn
               6 CallFunctionPositional(1)
               7 BuildTuple           (2)
               8 GetIter
-        >>    9 ForIter              (73)
+        >>    9 ForIter              (72)
              10 StoreLocal           (2, stop_exc)
 
   2          11 LoadNameAny          (3, self)
@@ -21,7 +21,7 @@ expression: "compile_exec(\"\\\nfor stop_exc in (StopIteration('spam'), StopAsyn
              15 CallFunctionPositional(1)
              16 LoadConst            (("type"))
              17 CallMethodKeyword    (1)
-             18 SetupWith            (70)
+             18 SetupWith            (69)
              19 Pop
 
   3          20 SetupExcept          (42)
@@ -48,41 +48,40 @@ expression: "compile_exec(\"\\\nfor stop_exc in (StopIteration('spam'), StopAsyn
              38 Resume               (3)
              39 WithCleanupFinish
              40 PopBlock
-             41 Jump                 (59)
+             41 Jump                 (58)
         >>   42 CopyItem             (1)
 
   6          43 LoadNameAny          (7, Exception)
-             44 TestOperation        (ExceptionMatch)
-             45 PopJumpIfFalse       (58)
-             46 StoreLocal           (8, ex)
+             44 JUMP_IF_NOT_EXC_MATCH(57)
+             45 StoreLocal           (8, ex)
 
-  7          47 LoadNameAny          (3, self)
-             48 LoadMethod           (9, assertIs)
-             49 LoadNameAny          (8, ex)
-             50 LoadNameAny          (2, stop_exc)
-             51 CallMethodPositional (2)
-             52 Pop
-             53 PopException
-             54 LoadConst            (None)
-             55 StoreLocal           (8, ex)
-             56 DeleteLocal          (8, ex)
-             57 Jump                 (68)
-        >>   58 Raise                (Reraise)
+  7          46 LoadNameAny          (3, self)
+             47 LoadMethod           (9, assertIs)
+             48 LoadNameAny          (8, ex)
+             49 LoadNameAny          (2, stop_exc)
+             50 CallMethodPositional (2)
+             51 Pop
+             52 PopException
+             53 LoadConst            (None)
+             54 StoreLocal           (8, ex)
+             55 DeleteLocal          (8, ex)
+             56 Jump                 (67)
+             57 Raise                (Reraise)
 
-  9     >>   59 LoadNameAny          (3, self)
-             60 LoadMethod           (10, fail)
-             61 LoadConst            ("")
-             62 LoadNameAny          (2, stop_exc)
-             63 FormatValue          (None)
-             64 LoadConst            (" was suppressed")
-             65 BuildString          (2)
-             66 CallMethodPositional (1)
-             67 Pop
+  9     >>   58 LoadNameAny          (3, self)
+             59 LoadMethod           (10, fail)
+             60 LoadConst            ("")
+             61 LoadNameAny          (2, stop_exc)
+             62 FormatValue          (None)
+             63 LoadConst            (" was suppressed")
+             64 BuildString          (2)
+             65 CallMethodPositional (1)
+             66 Pop
 
-  2     >>   68 PopBlock
-             69 EnterFinally
-        >>   70 WithCleanupStart
-             71 WithCleanupFinish
-             72 Jump                 (9)
-        >>   73 PopBlock
-             74 ReturnConst          (None)
+  2     >>   67 PopBlock
+             68 EnterFinally
+        >>   69 WithCleanupStart
+             70 WithCleanupFinish
+             71 Jump                 (9)
+        >>   72 PopBlock
+             73 ReturnConst          (None)

From c323c6c345c9a8fc1302bd88d5f2541d77b48db2 Mon Sep 17 00:00:00 2001
From: ShaharNaveh <50263213+ShaharNaveh@users.noreply.github.com>
Date: Fri, 28 Nov 2025 23:49:11 +0200
Subject: [PATCH 3/3] Set as have label

---
 ...ython_codegen__compile__tests__nested_double_async_with.snap | 2 +-
 crates/compiler-core/src/bytecode.rs                            | 1 +
 2 files changed, 2 insertions(+), 1 deletion(-)

diff --git a/crates/codegen/src/snapshots/rustpython_codegen__compile__tests__nested_double_async_with.snap b/crates/codegen/src/snapshots/rustpython_codegen__compile__tests__nested_double_async_with.snap
index d34398cb3b1..3042e35f179 100644
--- a/crates/codegen/src/snapshots/rustpython_codegen__compile__tests__nested_double_async_with.snap
+++ b/crates/codegen/src/snapshots/rustpython_codegen__compile__tests__nested_double_async_with.snap
@@ -66,7 +66,7 @@ expression: "compile_exec(\"\\\nfor stop_exc in (StopIteration('spam'), StopAsyn
              54 StoreLocal           (8, ex)
              55 DeleteLocal          (8, ex)
              56 Jump                 (67)
-             57 Raise                (Reraise)
+        >>   57 Raise                (Reraise)
 
   9     >>   58 LoadNameAny          (3, self)
              59 LoadMethod           (10, fail)
diff --git a/crates/compiler-core/src/bytecode.rs b/crates/compiler-core/src/bytecode.rs
index d7780bfd7b8..144054860e4 100644
--- a/crates/compiler-core/src/bytecode.rs
+++ b/crates/compiler-core/src/bytecode.rs
@@ -1405,6 +1405,7 @@ impl Instruction {
     pub const fn label_arg(&self) -> Option<Arg<Label>> {
         match self {
             Jump { target: l }
+            | JumpIfNotExcMatch(l)
             | PopJumpIfTrue { target: l }
             | PopJumpIfFalse { target: l }
             | JumpIfTrueOrPop { target: l }