diff --git a/evm/src/cpu/columns/ops.rs b/evm/src/cpu/columns/ops.rs
index bab27ea8..81d8414a 100644
--- a/evm/src/cpu/columns/ops.rs
+++ b/evm/src/cpu/columns/ops.rs
@@ -40,9 +40,7 @@ pub struct OpsColumnsView<T: Copy> {
     pub push: T,
     pub dup: T,
     pub swap: T,
-    // TODO: combine GET_CONTEXT and SET_CONTEXT into one flag
-    pub get_context: T,
-    pub set_context: T,
+    pub context_op: T,
     pub exit_kernel: T,
     // TODO: combine MLOAD_GENERAL and MSTORE_GENERAL into one flag
     pub mload_general: T,
diff --git a/evm/src/cpu/contextops.rs b/evm/src/cpu/contextops.rs
index 8c5bc485..55f14820 100644
--- a/evm/src/cpu/contextops.rs
+++ b/evm/src/cpu/contextops.rs
@@ -15,12 +15,31 @@ fn eval_packed_get<P: PackedField>(
     lv: &CpuColumnsView<P>,
     yield_constr: &mut ConstraintConsumer<P>,
 ) {
-    let filter = lv.op.get_context;
+    // If the opcode is GET_CONTEXT, then lv.opcode_bits[0] = 0
+    let filter = lv.op.context_op * (P::ONES - lv.opcode_bits[0]);
     let push_channel = lv.mem_channels[NUM_GP_CHANNELS - 1];
     yield_constr.constraint(filter * (push_channel.value[0] - lv.context));
     for &limb in &push_channel.value[1..] {
         yield_constr.constraint(filter * limb);
     }
+
+    // Stack constraints
+    let channel = lv.mem_channels[NUM_GP_CHANNELS - 1];
+    yield_constr.constraint(filter * (channel.used - P::ONES));
+    yield_constr.constraint(filter * channel.is_read);
+
+    yield_constr.constraint(filter * (channel.addr_context - lv.context));
+    yield_constr.constraint(
+        filter * (channel.addr_segment - P::Scalar::from_canonical_u64(Segment::Stack as u64)),
+    );
+    let addr_virtual = lv.stack_len;
+    yield_constr.constraint(filter * (channel.addr_virtual - addr_virtual));
+
+    // Unused channels
+    for i in 0..NUM_GP_CHANNELS - 1 {
+        let channel = lv.mem_channels[i];
+        yield_constr.constraint(filter * channel.used);
+    }
 }
 
 fn eval_ext_circuit_get<F: RichField + Extendable<D>, const D: usize>(
@@ -28,7 +47,11 @@ fn eval_ext_circuit_get<F: RichField + Extendable<D>, const D: usize>(
     lv: &CpuColumnsView<ExtensionTarget<D>>,
     yield_constr: &mut RecursiveConstraintConsumer<F, D>,
 ) {
-    let filter = lv.op.get_context;
+    let mut filter = lv.op.context_op;
+    let one = builder.one_extension();
+    let minus = builder.sub_extension(one, lv.opcode_bits[0]);
+    filter = builder.mul_extension(filter, minus);
+
     let push_channel = lv.mem_channels[NUM_GP_CHANNELS - 1];
     {
         let diff = builder.sub_extension(push_channel.value[0], lv.context);
@@ -39,6 +62,45 @@ fn eval_ext_circuit_get<F: RichField + Extendable<D>, const D: usize>(
         let constr = builder.mul_extension(filter, limb);
         yield_constr.constraint(builder, constr);
     }
+
+    // Stack constraints
+    let channel = lv.mem_channels[NUM_GP_CHANNELS - 1];
+
+    {
+        let constr = builder.mul_sub_extension(filter, channel.used, filter);
+        yield_constr.constraint(builder, constr);
+    }
+    {
+        let constr = builder.mul_extension(filter, channel.is_read);
+        yield_constr.constraint(builder, constr);
+    }
+
+    {
+        let diff = builder.sub_extension(channel.addr_context, lv.context);
+        let constr = builder.mul_extension(filter, diff);
+        yield_constr.constraint(builder, constr);
+    }
+    {
+        let constr = builder.arithmetic_extension(
+            F::ONE,
+            -F::from_canonical_u64(Segment::Stack as u64),
+            filter,
+            channel.addr_segment,
+            filter,
+        );
+        yield_constr.constraint(builder, constr);
+    }
+    {
+        let diff = builder.sub_extension(channel.addr_virtual, lv.stack_len);
+        let constr = builder.arithmetic_extension(F::ONE, F::ZERO, filter, diff, filter);
+        yield_constr.constraint(builder, constr);
+    }
+
+    for i in 0..NUM_GP_CHANNELS - 1 {
+        let channel = lv.mem_channels[i];
+        let constr = builder.mul_extension(filter, channel.used);
+        yield_constr.constraint(builder, constr);
+    }
 }
 
 fn eval_packed_set<P: PackedField>(
@@ -46,7 +108,7 @@ fn eval_packed_set<P: PackedField>(
     nv: &CpuColumnsView<P>,
     yield_constr: &mut ConstraintConsumer<P>,
 ) {
-    let filter = lv.op.set_context;
+    let filter = lv.op.context_op * lv.opcode_bits[0];
     let pop_channel = lv.mem_channels[0];
     let write_old_sp_channel = lv.mem_channels[1];
     let read_new_sp_channel = lv.mem_channels[2];
@@ -94,7 +156,8 @@ fn eval_ext_circuit_set<F: RichField + Extendable<D>, const D: usize>(
     nv: &CpuColumnsView<ExtensionTarget<D>>,
     yield_constr: &mut RecursiveConstraintConsumer<F, D>,
 ) {
-    let filter = lv.op.set_context;
+    let mut filter = lv.op.context_op;
+    filter = builder.mul_extension(filter, lv.opcode_bits[0]);
     let pop_channel = lv.mem_channels[0];
     let write_old_sp_channel = lv.mem_channels[1];
     let read_new_sp_channel = lv.mem_channels[2];
diff --git a/evm/src/cpu/control_flow.rs b/evm/src/cpu/control_flow.rs
index fd0688b3..0bea5c7c 100644
--- a/evm/src/cpu/control_flow.rs
+++ b/evm/src/cpu/control_flow.rs
@@ -8,7 +8,7 @@ use crate::constraint_consumer::{ConstraintConsumer, RecursiveConstraintConsumer
 use crate::cpu::columns::{CpuColumnsView, COL_MAP};
 use crate::cpu::kernel::aggregator::KERNEL;
 
-const NATIVE_INSTRUCTIONS: [usize; 29] = [
+const NATIVE_INSTRUCTIONS: [usize; 28] = [
     COL_MAP.op.add,
     COL_MAP.op.mul,
     COL_MAP.op.sub,
@@ -37,8 +37,7 @@ const NATIVE_INSTRUCTIONS: [usize; 29] = [
     // not PUSH (need to increment by more than 1)
     COL_MAP.op.dup,
     COL_MAP.op.swap,
-    COL_MAP.op.get_context,
-    COL_MAP.op.set_context,
+    COL_MAP.op.context_op,
     // not EXIT_KERNEL (performs a jump)
     COL_MAP.op.mload_general,
     COL_MAP.op.mstore_general,
diff --git a/evm/src/cpu/decode.rs b/evm/src/cpu/decode.rs
index a2918d4c..86f2c893 100644
--- a/evm/src/cpu/decode.rs
+++ b/evm/src/cpu/decode.rs
@@ -22,7 +22,7 @@ use crate::cpu::columns::{CpuColumnsView, COL_MAP};
 /// behavior.
 /// Note: invalid opcodes are not represented here. _Any_ opcode is permitted to decode to
 /// `is_invalid`. The kernel then verifies that the opcode was _actually_ invalid.
-const OPCODES: [(u8, usize, bool, usize); 32] = [
+const OPCODES: [(u8, usize, bool, usize); 31] = [
     // (start index of block, number of top bits to check (log2), kernel-only, flag column)
     (0x01, 0, false, COL_MAP.op.add),
     (0x02, 0, false, COL_MAP.op.mul),
@@ -49,11 +49,10 @@ const OPCODES: [(u8, usize, bool, usize); 32] = [
     (0x58, 0, false, COL_MAP.op.pc),
     (0x5b, 0, false, COL_MAP.op.jumpdest),
     (0x5f, 0, false, COL_MAP.op.push0),
-    (0x60, 5, false, COL_MAP.op.push), // 0x60-0x7f
-    (0x80, 4, false, COL_MAP.op.dup),  // 0x80-0x8f
-    (0x90, 4, false, COL_MAP.op.swap), // 0x90-0x9f
-    (0xf6, 0, true, COL_MAP.op.get_context),
-    (0xf7, 0, true, COL_MAP.op.set_context),
+    (0x60, 5, false, COL_MAP.op.push),      // 0x60-0x7f
+    (0x80, 4, false, COL_MAP.op.dup),       // 0x80-0x8f
+    (0x90, 4, false, COL_MAP.op.swap),      // 0x90-0x9f
+    (0xf6, 1, true, COL_MAP.op.context_op), // 0xf6-0xf7
     (0xf9, 0, true, COL_MAP.op.exit_kernel),
     (0xfb, 0, true, COL_MAP.op.mload_general),
     (0xfc, 0, true, COL_MAP.op.mstore_general),
diff --git a/evm/src/cpu/gas.rs b/evm/src/cpu/gas.rs
index 75ece520..61690005 100644
--- a/evm/src/cpu/gas.rs
+++ b/evm/src/cpu/gas.rs
@@ -48,8 +48,7 @@ const SIMPLE_OPCODES: OpsColumnsView<Option<u32>> = OpsColumnsView {
     push: G_VERYLOW,
     dup: G_VERYLOW,
     swap: G_VERYLOW,
-    get_context: KERNEL_ONLY_INSTR,
-    set_context: KERNEL_ONLY_INSTR,
+    context_op: KERNEL_ONLY_INSTR,
     exit_kernel: None,
     mload_general: KERNEL_ONLY_INSTR,
     mstore_general: KERNEL_ONLY_INSTR,
diff --git a/evm/src/cpu/stack.rs b/evm/src/cpu/stack.rs
index 760f4041..8ffc152d 100644
--- a/evm/src/cpu/stack.rs
+++ b/evm/src/cpu/stack.rs
@@ -107,12 +107,7 @@ const STACK_BEHAVIORS: OpsColumnsView<Option<StackBehavior>> = OpsColumnsView {
     push: None, // TODO
     dup: None,
     swap: None,
-    get_context: Some(StackBehavior {
-        num_pops: 0,
-        pushes: true,
-        disable_other_channels: true,
-    }),
-    set_context: None, // SET_CONTEXT is special since it involves the old and the new stack.
+    context_op: None, // SET_CONTEXT is special since it involves the old and the new stack.
     exit_kernel: Some(StackBehavior {
         num_pops: 1,
         pushes: false,
diff --git a/evm/src/witness/gas.rs b/evm/src/witness/gas.rs
index 4c7947bb..13913cce 100644
--- a/evm/src/witness/gas.rs
+++ b/evm/src/witness/gas.rs
@@ -42,8 +42,7 @@ pub(crate) fn gas_to_charge(op: Operation) -> u64 {
         Push(1..) => G_VERYLOW,
         Dup(_) => G_VERYLOW,
         Swap(_) => G_VERYLOW,
-        GetContext => KERNEL_ONLY_INSTR,
-        SetContext => KERNEL_ONLY_INSTR,
+        ContextOp(_) => KERNEL_ONLY_INSTR,
         ExitKernel => KERNEL_ONLY_INSTR,
         MloadGeneral => KERNEL_ONLY_INSTR,
         MstoreGeneral => KERNEL_ONLY_INSTR,
diff --git a/evm/src/witness/operation.rs b/evm/src/witness/operation.rs
index 13619b96..05c22536 100644
--- a/evm/src/witness/operation.rs
+++ b/evm/src/witness/operation.rs
@@ -45,8 +45,7 @@ pub(crate) enum Operation {
     Push(u8),
     Dup(u8),
     Swap(u8),
-    GetContext,
-    SetContext,
+    ContextOp(bool),
     ExitKernel,
     MloadGeneral,
     MstoreGeneral,
@@ -293,6 +292,19 @@ pub(crate) fn generate_jumpdest<F: Field>(
     Ok(())
 }
 
+pub(crate) fn generate_context_op<F: Field>(
+    is_set: bool,
+    state: &mut GenerationState<F>,
+    row: CpuColumnsView<F>,
+) -> Result<(), ProgramError> {
+    // SET_CONTEXT uses mem_channels[0..=2]
+    if is_set {
+        generate_set_context(state, row)
+    } else {
+        generate_get_context(state, row)
+    }
+}
+
 pub(crate) fn generate_get_context<F: Field>(
     state: &mut GenerationState<F>,
     mut row: CpuColumnsView<F>,
diff --git a/evm/src/witness/transition.rs b/evm/src/witness/transition.rs
index a8425a66..aaf66970 100644
--- a/evm/src/witness/transition.rs
+++ b/evm/src/witness/transition.rs
@@ -134,8 +134,8 @@ fn decode(registers: RegistersState, opcode: u8) -> Result<Operation, ProgramErr
         (0xf3, _) => Ok(Operation::Syscall(opcode, 2, false)), // RETURN
         (0xf4, _) => Ok(Operation::Syscall(opcode, 6, false)), // DELEGATECALL
         (0xf5, _) => Ok(Operation::Syscall(opcode, 4, false)), // CREATE2
-        (0xf6, true) => Ok(Operation::GetContext),
-        (0xf7, true) => Ok(Operation::SetContext),
+        (0xf6, true) => Ok(Operation::ContextOp(false)),       // GET_CONTEXT
+        (0xf7, true) => Ok(Operation::ContextOp(true)),        // SET_CONTEXT
         (0xf9, true) => Ok(Operation::ExitKernel),
         (0xfa, _) => Ok(Operation::Syscall(opcode, 6, false)), // STATICCALL
         (0xfb, true) => Ok(Operation::MloadGeneral),
@@ -182,8 +182,7 @@ fn fill_op_flag<F: Field>(op: Operation, row: &mut CpuColumnsView<F>) {
         Operation::Jump | Operation::Jumpi => &mut flags.jumps,
         Operation::Pc => &mut flags.pc,
         Operation::Jumpdest => &mut flags.jumpdest,
-        Operation::GetContext => &mut flags.get_context,
-        Operation::SetContext => &mut flags.set_context,
+        Operation::ContextOp(_) => &mut flags.context_op,
         Operation::ExitKernel => &mut flags.exit_kernel,
         Operation::MloadGeneral => &mut flags.mload_general,
         Operation::MstoreGeneral => &mut flags.mstore_general,
@@ -219,8 +218,7 @@ fn perform_op<F: Field>(
         Operation::Jumpi => generate_jumpi(state, row)?,
         Operation::Pc => generate_pc(state, row)?,
         Operation::Jumpdest => generate_jumpdest(state, row)?,
-        Operation::GetContext => generate_get_context(state, row)?,
-        Operation::SetContext => generate_set_context(state, row)?,
+        Operation::ContextOp(is_set) => generate_context_op(is_set, state, row)?,
         Operation::ExitKernel => generate_exit_kernel(state, row)?,
         Operation::MloadGeneral => generate_mload_general(state, row)?,
         Operation::MstoreGeneral => generate_mstore_general(state, row)?,