diff --git a/crates/cpu/Cargo.toml b/crates/cpu/Cargo.toml
index ba472bb..f346e88 100644
--- a/crates/cpu/Cargo.toml
+++ b/crates/cpu/Cargo.toml
@@ -33,6 +33,3 @@ hex-literal.workspace = true
 regex = "1.12.2"
 sha2.workspace = true
 which.workspace = true
-
-[lints.rust]
-unexpected_cfgs = { level = "warn", check-cfg = ['cfg(todo)'] }
diff --git a/crates/cpu/src/config.rs b/crates/cpu/src/config.rs
index 2dfa8b2..9826955 100644
--- a/crates/cpu/src/config.rs
+++ b/crates/cpu/src/config.rs
@@ -1,6 +1,12 @@
 // SPDX-License-Identifier: LGPL-3.0-or-later
 // See Notices.txt for copyright information
-use crate::{instruction::CONST_ZERO_UNIT_NUM, unit::UnitKind};
+use crate::{
+    instruction::{CONST_ZERO_UNIT_NUM, MOpTrait, PRegNum, RenamedMOp, UnitNum, UnitOutRegNum},
+    unit::{
+        UnitCancelInput, UnitKind, UnitOutputWrite,
+        unit_base::{UnitForwardingInfo, UnitToRegAlloc},
+    },
+};
 use fayalite::prelude::*;
 use serde::{Deserialize, Serialize};
 use std::num::NonZeroUsize;
@@ -95,14 +101,55 @@ impl CpuConfig {
     pub fn unit_num_width(&self) -> usize {
         UInt::range(CONST_ZERO_UNIT_NUM..self.non_const_unit_nums().end).width()
     }
+    pub fn unit_num(&self) -> UnitNum<DynSize> {
+        UnitNum[self.unit_num_width()]
+    }
+    pub fn unit_out_reg_num(&self) -> UnitOutRegNum<DynSize> {
+        UnitOutRegNum[self.out_reg_num_width]
+    }
+    pub fn p_reg_num(&self) -> PRegNum<DynSize, DynSize> {
+        PRegNum[self.unit_num_width()][self.out_reg_num_width]
+    }
     pub fn p_reg_num_width(&self) -> usize {
         self.unit_num_width() + self.out_reg_num_width
     }
+    pub fn renamed_mop_in_unit(&self) -> RenamedMOp<UnitOutRegNum<DynSize>, DynSize> {
+        RenamedMOp[self.unit_out_reg_num()][self.p_reg_num_width()]
+    }
+    pub fn unit_output_write(&self) -> UnitOutputWrite<DynSize> {
+        UnitOutputWrite[self.out_reg_num_width]
+    }
+    pub fn unit_output_writes(&self) -> Array<HdlOption<UnitOutputWrite<DynSize>>> {
+        Array[HdlOption[self.unit_output_write()]][self.non_const_unit_nums().len()]
+    }
+    pub fn unit_cancel_input(&self) -> UnitCancelInput<DynSize> {
+        UnitCancelInput[self.out_reg_num_width]
+    }
+    pub fn unit_forwarding_info(&self) -> UnitForwardingInfo<DynSize, DynSize, DynSize> {
+        UnitForwardingInfo[self.unit_num_width()][self.out_reg_num_width]
+            [self.non_const_unit_nums().len()]
+    }
     pub fn unit_max_in_flight(&self, unit_index: usize) -> NonZeroUsize {
         self.units[unit_index]
             .max_in_flight
             .unwrap_or(self.default_unit_max_in_flight)
     }
+    pub fn unit_to_reg_alloc<
+        MOp: Type + MOpTrait<DestReg = UnitOutRegNum<DynSize>, SrcRegWidth = DynSize>,
+        ExtraOut: Type,
+    >(
+        &self,
+        mop_ty: MOp,
+        extra_out_ty: ExtraOut,
+    ) -> UnitToRegAlloc<MOp, ExtraOut, DynSize, DynSize, DynSize> {
+        assert_eq!(
+            mop_ty.dest_reg_ty(),
+            self.unit_out_reg_num(),
+            "inconsistent types",
+        );
+        UnitToRegAlloc[mop_ty][extra_out_ty][self.unit_num_width()][self.out_reg_num_width]
+            [self.non_const_unit_nums().len()]
+    }
     pub fn fetch_width_in_bytes(&self) -> usize {
         1usize
             .checked_shl(self.log2_fetch_width_in_bytes.into())
@@ -141,18 +188,6 @@ impl CpuConfig {
     }
 }
 
-#[hdl(get(|c| c.out_reg_num_width))]
-pub type CpuConfigOutRegNumWidth<C: PhantomConstGet<CpuConfig>> = DynSize;
-
-#[hdl(get(|c| c.unit_num_width()))]
-pub type CpuConfigUnitNumWidth<C: PhantomConstGet<CpuConfig>> = DynSize;
-
-#[hdl(get(|c| c.p_reg_num_width()))]
-pub type CpuConfigPRegNumWidth<C: PhantomConstGet<CpuConfig>> = DynSize;
-
-#[hdl(get(|c| c.non_const_unit_nums().len()))]
-pub type CpuConfigUnitCount<C: PhantomConstGet<CpuConfig>> = DynSize;
-
 #[hdl(get(|c| c.fetch_width.get()))]
 pub type CpuConfigFetchWidth<C: PhantomConstGet<CpuConfig>> = DynSize;
 
diff --git a/crates/cpu/src/instruction.rs b/crates/cpu/src/instruction.rs
index ac87efc..1f9f5ae 100644
--- a/crates/cpu/src/instruction.rs
+++ b/crates/cpu/src/instruction.rs
@@ -1,7 +1,6 @@
 // SPDX-License-Identifier: LGPL-3.0-or-later
 // See Notices.txt for copyright information
 use crate::{
-    config::{CpuConfig, CpuConfigOutRegNumWidth, CpuConfigUnitNumWidth, PhantomConstCpuConfig},
     register::{PRegFlags, PRegFlagsViewTrait, PRegValue, ViewUnused},
     unit::UnitMOp,
     util::{Rotate, range_u32_len},
@@ -2596,21 +2595,19 @@ impl<DestReg: Type, SrcRegWidth: Size> MoveRegMOp<DestReg, SrcRegWidth> {
     }
 }
 
-#[hdl(cmp_eq, no_static)]
+#[hdl(cmp_eq)]
 /// there may be more than one unit of a given kind, so UnitNum is not the same as UnitKind.
 /// zero is used for built-in constants, such as the zero register
-pub struct UnitNum<C: PhantomConstGet<CpuConfig>> {
-    pub adj_value: UIntType<CpuConfigUnitNumWidth<C>>,
-    pub config: C,
+pub struct UnitNum<Width: Size> {
+    pub adj_value: UIntType<Width>,
 }
 
-impl<C: PhantomConstCpuConfig> UnitNum<C> {
+impl<Width: Size> UnitNum<Width> {
     #[hdl]
     pub fn const_zero(self) -> Expr<Self> {
         #[hdl]
         UnitNum {
             adj_value: CONST_ZERO_UNIT_NUM.cast_to(self.adj_value),
-            config: self.config,
         }
     }
     #[hdl]
@@ -2618,7 +2615,6 @@ impl<C: PhantomConstCpuConfig> UnitNum<C> {
         #[hdl]
         UnitNum {
             adj_value: (index + 1).cast_to(self.adj_value),
-            config: self.config,
         }
     }
     pub fn is_index(expr: impl ToExpr<Type = Self>, index: usize) -> Expr<Bool> {
@@ -2626,9 +2622,7 @@ impl<C: PhantomConstCpuConfig> UnitNum<C> {
         expr.ty().from_index(index).adj_value.cmp_eq(expr.adj_value)
     }
     #[hdl]
-    pub fn as_index(
-        expr: impl ToExpr<Type = Self>,
-    ) -> Expr<HdlOption<UIntType<CpuConfigUnitNumWidth<C>>>> {
+    pub fn as_index(expr: impl ToExpr<Type = Self>) -> Expr<HdlOption<UIntType<Width>>> {
         let expr = expr.to_expr();
         #[hdl]
         let unit_index = wire(HdlOption[expr.ty().adj_value]);
@@ -2646,20 +2640,19 @@ impl<C: PhantomConstCpuConfig> UnitNum<C> {
 
 pub const CONST_ZERO_UNIT_NUM: usize = 0;
 
-#[hdl(cmp_eq, no_static)]
-pub struct UnitOutRegNum<C: PhantomConstGet<CpuConfig>> {
-    pub value: UIntType<CpuConfigOutRegNumWidth<C>>,
-    pub config: C,
+#[hdl(cmp_eq)]
+pub struct UnitOutRegNum<Width: Size> {
+    pub value: UIntType<Width>,
 }
 
-#[hdl(cmp_eq, no_static)]
+#[hdl(cmp_eq)]
 /// Physical Register Number -- registers in the CPU's backend
-pub struct PRegNum<C: PhantomConstGet<CpuConfig>> {
-    pub unit_num: UnitNum<C>,
-    pub unit_out_reg: UnitOutRegNum<C>,
+pub struct PRegNum<UnitNumWidth: Size, OutRegNumWidth: Size> {
+    pub unit_num: UnitNum<UnitNumWidth>,
+    pub unit_out_reg: UnitOutRegNum<OutRegNumWidth>,
 }
 
-impl<C: PhantomConstCpuConfig> PRegNum<C> {
+impl<UnitNumWidth: Size, OutRegNumWidth: Size> PRegNum<UnitNumWidth, OutRegNumWidth> {
     #[hdl]
     pub fn const_zero(self) -> Expr<Self> {
         #[hdl]
@@ -2668,7 +2661,6 @@ impl<C: PhantomConstCpuConfig> PRegNum<C> {
             unit_out_reg: #[hdl]
             UnitOutRegNum {
                 value: 0u8.cast_to(self.unit_out_reg.value),
-                config: self.unit_out_reg.config,
             },
         }
     }
diff --git a/crates/cpu/src/lib.rs b/crates/cpu/src/lib.rs
index 2ba775e..7131241 100644
--- a/crates/cpu/src/lib.rs
+++ b/crates/cpu/src/lib.rs
@@ -7,9 +7,7 @@ pub mod instruction;
 pub mod main_memory_and_io;
 pub mod next_pc;
 pub mod powerisa_instructions_xml;
-#[cfg(todo)]
 pub mod reg_alloc;
 pub mod register;
-pub mod rename_execute_retire;
 pub mod unit;
 pub mod util;
diff --git a/crates/cpu/src/rename_execute_retire.rs b/crates/cpu/src/rename_execute_retire.rs
deleted file mode 100644
index ee7a747..0000000
--- a/crates/cpu/src/rename_execute_retire.rs
+++ /dev/null
@@ -1,295 +0,0 @@
-// SPDX-License-Identifier: LGPL-3.0-or-later
-// See Notices.txt for copyright information
-
-use crate::{
-    config::{
-        CpuConfig, CpuConfigFetchWidth, CpuConfigPRegNumWidth, CpuConfigRobSize,
-        PhantomConstCpuConfig,
-    },
-    instruction::{MOp, MOpRegNum, PRegNum, RenamedMOp},
-    next_pc::{RetireToNextPcInterfaceInner, SimValueDefault},
-    util::array_vec::ArrayVec,
-};
-use fayalite::{
-    int::UIntInRangeInclusiveType, prelude::*, ty::OpaqueSimValue, util::ready_valid::ReadyValid,
-};
-use std::collections::VecDeque;
-
-#[hdl]
-/// A &micro;Op along with the state needed for this instance of the &micro;Op.
-pub struct MOpInstance<MOp> {
-    pub fetch_block_id: UInt<8>,
-    pub id: UInt<12>,
-    pub pc: UInt<64>,
-    /// initialized to 0 by decoder, overwritten by `next_pc()`
-    pub predicted_next_pc: UInt<64>,
-    pub size_in_bytes: UInt<4>,
-    /// `true` if this &micro;Op is the first &micro;Op in the ISA-level instruction.
-    /// In general, a single &micro;Op can't be cancelled by itself,
-    /// it needs to be cancelled along with all other &micro;Ops that
-    /// come from the same ISA-level instruction.
-    pub is_first_mop_in_insn: Bool,
-    pub mop: MOp,
-}
-
-#[hdl(no_static)]
-/// TODO: merge with [`crate::next_pc::PostDecodeOutputInterface`]
-pub struct PostDecodeOutputInterface<C: PhantomConstGet<CpuConfig>> {
-    pub insns: ArrayVec<MOpInstance<MOp>, CpuConfigFetchWidth<C>>,
-    #[hdl(flip)]
-    pub ready: UIntInRangeInclusiveType<ConstUsize<0>, CpuConfigFetchWidth<C>>,
-    /// tells the rename/execute/retire circuit to cancel all non-retired instructions
-    pub cancel: ReadyValid<()>,
-    pub config: C,
-}
-
-#[hdl(no_static)]
-/// handles updating speculative branch predictor state (e.g. branch histories)
-/// when instructions retire, as well as updating state when a
-/// branch instruction is mis-speculated.
-pub struct RetireToNextPcInterface<C: PhantomConstGet<CpuConfig>> {
-    pub inner: ReadyValid<RetireToNextPcInterfaceInner<C>>,
-    /// only for debugging
-    pub next_insns: HdlOption<ArrayVec<MOpInstance<MOp>, CpuConfigRobSize<C>>>,
-}
-
-fn zeroed<T: Type>(ty: T) -> SimValue<T> {
-    SimValue::from_opaque(
-        ty,
-        OpaqueSimValue::from_bits(UInt::new(ty.canonical().bit_width()).zero()),
-    )
-}
-
-impl<C: PhantomConstCpuConfig> SimValueDefault for RenameExecuteRetireDebugState<C> {
-    fn sim_value_default(self) -> SimValue<Self> {
-        zeroed(self)
-    }
-}
-
-#[derive(Debug, Clone)]
-struct RenameTable<C: PhantomConstCpuConfig> {
-    entries: Box<[SimValue<PRegNum<C>>; 1 << MOpRegNum::WIDTH]>,
-    config: C,
-}
-
-impl<C: PhantomConstCpuConfig> RenameTable<C> {
-    fn new(config: C) -> Self {
-        Self {
-            entries: vec![PRegNum[config].const_zero().into_sim_value(); 1 << MOpRegNum::WIDTH]
-                .try_into()
-                .expect("size is known to match"),
-            config,
-        }
-    }
-    fn to_debug_state(&self) -> SimValue<Array<PRegNum<C>, { 1 << MOpRegNum::WIDTH }>> {
-        self.entries
-            .to_sim_value_with_type(Array[PRegNum[self.config]][ConstUsize])
-    }
-}
-
-#[hdl(no_static)]
-struct RobEntryDebugState<C: PhantomConstGet<CpuConfig>> {
-    mop: MOpInstance<RenamedMOp<PRegNum<C>, CpuConfigPRegNumWidth<C>>>,
-    config: C,
-}
-
-impl<C: PhantomConstCpuConfig> SimValueDefault for RobEntryDebugState<C> {
-    fn sim_value_default(self) -> SimValue<Self> {
-        zeroed(self)
-    }
-}
-
-#[derive(Debug)]
-struct RobEntry<C: PhantomConstCpuConfig> {
-    mop: SimValue<MOpInstance<RenamedMOp<PRegNum<C>, CpuConfigPRegNumWidth<C>>>>,
-    config: C,
-}
-
-#[hdl]
-struct OrigMOpQueueEntryDebugState {
-    mop: MOpInstance<MOp>,
-    /// number of renamed &micro;Ops that this non-renamed &micro;Op corresponds to
-    renamed_mop_count: UInt<8>,
-}
-
-#[derive(Debug)]
-struct OrigMOpQueueEntry {
-    mop: SimValue<MOpInstance<MOp>>,
-    /// number of renamed &micro;Ops that this non-renamed &micro;Op corresponds to
-    renamed_mop_count: u8,
-}
-
-#[hdl(no_static)]
-pub struct RenameExecuteRetireDebugState<C: PhantomConstGet<CpuConfig>> {
-    rename_table: Array<PRegNum<C>, { 1 << MOpRegNum::WIDTH }>,
-    retire_rename_table: Array<PRegNum<C>, { 1 << MOpRegNum::WIDTH }>,
-    rob: ArrayVec<RobEntryDebugState<C>, CpuConfigRobSize<C>>,
-    orig_mop_queue: ArrayVec<OrigMOpQueueEntryDebugState, CpuConfigRobSize<C>>,
-    cancelling: Bool,
-}
-
-#[derive(Debug)]
-struct RenameExecuteRetireState<C: PhantomConstCpuConfig> {
-    rename_table: RenameTable<C>,
-    retire_rename_table: RenameTable<C>,
-    rob: VecDeque<RobEntry<C>>,
-    orig_mop_queue: VecDeque<OrigMOpQueueEntry>,
-    cancelling: bool,
-    config: C,
-}
-
-impl<C: PhantomConstCpuConfig> RenameExecuteRetireState<C> {
-    fn new(config: C) -> Self {
-        let rename_table = RenameTable::new(config);
-        Self {
-            rename_table: rename_table.clone(),
-            retire_rename_table: rename_table,
-            rob: VecDeque::with_capacity(CpuConfigRobSize[config]),
-            orig_mop_queue: VecDeque::with_capacity(CpuConfigRobSize[config]),
-            cancelling: false,
-            config,
-        }
-    }
-    #[hdl]
-    async fn write_for_debug(
-        &self,
-        sim: &mut ExternModuleSimulationState,
-        state_for_debug: Expr<RenameExecuteRetireDebugState<C>>,
-    ) {
-        let Self {
-            ref rename_table,
-            ref retire_rename_table,
-            ref rob,
-            ref orig_mop_queue,
-            cancelling,
-            config,
-        } = *self;
-        sim.write(
-            state_for_debug,
-            #[hdl(sim)]
-            RenameExecuteRetireDebugState::<_> {
-                rename_table: rename_table.to_debug_state(),
-                retire_rename_table: retire_rename_table.to_debug_state(),
-                rob: state_for_debug
-                    .ty()
-                    .rob
-                    .from_iter_sim(
-                        zeroed(RobEntryDebugState[config]),
-                        rob.iter().map(|entry| {
-                            let RobEntry { mop, config: _ } = entry;
-                            #[hdl(sim)]
-                            RobEntryDebugState::<_> { mop, config }
-                        }),
-                    )
-                    .expect("known to fit"),
-                orig_mop_queue: state_for_debug
-                    .ty()
-                    .orig_mop_queue
-                    .from_iter_sim(
-                        zeroed(OrigMOpQueueEntryDebugState),
-                        orig_mop_queue.iter().map(|entry| {
-                            let OrigMOpQueueEntry {
-                                mop,
-                                renamed_mop_count,
-                            } = entry;
-                            #[hdl(sim)]
-                            OrigMOpQueueEntryDebugState {
-                                mop,
-                                renamed_mop_count,
-                            }
-                        }),
-                    )
-                    .expect("known to fit"),
-                cancelling,
-            },
-        )
-        .await;
-    }
-    #[hdl]
-    async fn write_to_next_pc_next_insns(
-        &self,
-        sim: &mut ExternModuleSimulationState,
-        next_insns: Expr<HdlOption<ArrayVec<MOpInstance<MOp>, CpuConfigRobSize<C>>>>,
-    ) {
-        sim.write(
-            next_insns,
-            #[hdl(sim)]
-            (next_insns.ty()).HdlSome(
-                next_insns
-                    .ty()
-                    .HdlSome
-                    .from_iter_sim(
-                        zeroed(MOpInstance[MOp]),
-                        self.orig_mop_queue.iter().map(|entry| &entry.mop),
-                    )
-                    .expect("known to fit"),
-            ),
-        )
-        .await;
-    }
-}
-
-#[hdl]
-async fn rename_execute_retire_run(
-    mut sim: ExternModuleSimulationState,
-    cd: Expr<ClockDomain>,
-    from_post_decode: Expr<PostDecodeOutputInterface<PhantomConst<CpuConfig>>>,
-    to_next_pc: Expr<RetireToNextPcInterface<PhantomConst<CpuConfig>>>,
-    state_for_debug: Expr<RenameExecuteRetireDebugState<PhantomConst<CpuConfig>>>,
-    config: PhantomConst<CpuConfig>,
-) {
-    let mut state = RenameExecuteRetireState::new(config);
-    loop {
-        state
-            .write_to_next_pc_next_insns(&mut sim, to_next_pc.next_insns)
-            .await;
-        state.write_for_debug(&mut sim, state_for_debug).await;
-        sim.wait_for_clock_edge(cd.clk).await;
-        todo!("step state based on I/O");
-    }
-}
-
-#[hdl_module(extern)]
-pub fn rename_execute_retire(config: PhantomConst<CpuConfig>) {
-    #[hdl]
-    let cd: ClockDomain = m.input();
-    #[hdl]
-    let from_post_decode: PostDecodeOutputInterface<PhantomConst<CpuConfig>> =
-        m.input(PostDecodeOutputInterface[config]);
-    #[hdl]
-    let to_next_pc: RetireToNextPcInterface<PhantomConst<CpuConfig>> =
-        m.output(RetireToNextPcInterface[config]);
-    #[hdl]
-    let state_for_debug: RenameExecuteRetireDebugState<PhantomConst<CpuConfig>> =
-        m.output(RenameExecuteRetireDebugState[config]);
-    m.register_clock_for_past(cd.clk);
-    m.extern_module_simulation_fn(
-        (cd, from_post_decode, to_next_pc, state_for_debug, config),
-        |(cd, from_post_decode, to_next_pc, state_for_debug, config), mut sim| async move {
-            sim.write(state_for_debug, state_for_debug.ty().sim_value_default())
-                .await;
-            sim.resettable(
-                cd,
-                |mut sim: ExternModuleSimulationState| async move {
-                    sim.write(from_post_decode.ready, 0usize).await;
-                    sim.write(from_post_decode.cancel.ready, false).await;
-                    sim.write(to_next_pc.inner.data, to_next_pc.ty().inner.data.HdlNone())
-                        .await;
-                    sim.write(to_next_pc.next_insns, to_next_pc.ty().next_insns.HdlNone())
-                        .await;
-                },
-                |sim, ()| {
-                    rename_execute_retire_run(
-                        sim,
-                        cd,
-                        from_post_decode,
-                        to_next_pc,
-                        state_for_debug,
-                        config,
-                    )
-                },
-            )
-            .await;
-        },
-    );
-}
diff --git a/crates/cpu/src/unit.rs b/crates/cpu/src/unit.rs
index e59b892..400358c 100644
--- a/crates/cpu/src/unit.rs
+++ b/crates/cpu/src/unit.rs
@@ -2,7 +2,7 @@
 // See Notices.txt for copyright information
 
 use crate::{
-    config::{CpuConfig, PhantomConstCpuConfig},
+    config::CpuConfig,
     instruction::{
         AluBranchMOp, LoadStoreMOp, MOp, MOpDestReg, MOpInto, MOpRegNum, MOpTrait,
         MOpVariantVisitOps, MOpVariantVisitor, MOpVisitVariants, RenamedMOp, UnitOutRegNum,
@@ -48,7 +48,7 @@ macro_rules! all_units {
         }
 
         impl $UnitKind {
-            pub fn unit(self, config: PhantomConst<CpuConfig>, unit_index: usize) -> DynUnit {
+            pub fn unit(self, config: &CpuConfig, unit_index: usize) -> DynUnit {
                 match self {
                     $($UnitKind::$Unit => $create_dyn_unit_fn(config, unit_index),)*
                 }
@@ -277,9 +277,9 @@ pub struct UnitResultCompleted<ExtraOut> {
     pub extra_out: ExtraOut,
 }
 
-#[hdl(cmp_eq, no_static)]
-pub struct UnitOutputWrite<C: PhantomConstGet<CpuConfig>> {
-    pub which: UnitOutRegNum<C>,
+#[hdl(cmp_eq)]
+pub struct UnitOutputWrite<OutRegNumWidth: Size> {
+    pub which: UnitOutRegNum<OutRegNumWidth>,
     pub value: PRegValue,
 }
 
@@ -300,21 +300,21 @@ impl<ExtraOut: Type> UnitResult<ExtraOut> {
     }
 }
 
-#[hdl(no_static)]
-pub struct UnitOutput<C: PhantomConstGet<CpuConfig>, ExtraOut> {
-    pub which: UnitOutRegNum<C>,
+#[hdl]
+pub struct UnitOutput<OutRegNumWidth: Size, ExtraOut> {
+    pub which: UnitOutRegNum<OutRegNumWidth>,
     pub result: UnitResult<ExtraOut>,
 }
 
-impl<C: PhantomConstCpuConfig, ExtraOut: Type> UnitOutput<C, ExtraOut> {
+impl<OutRegNumWidth: Size, ExtraOut: Type> UnitOutput<OutRegNumWidth, ExtraOut> {
     pub fn extra_out_ty(self) -> ExtraOut {
         self.result.extra_out_ty()
     }
 }
 
-#[hdl(cmp_eq, no_static)]
-pub struct UnitCancelInput<C: PhantomConstGet<CpuConfig>> {
-    pub which: UnitOutRegNum<C>,
+#[hdl(cmp_eq)]
+pub struct UnitCancelInput<OutRegNumWidth: Size> {
+    pub which: UnitOutRegNum<OutRegNumWidth>,
 }
 
 pub trait UnitTrait:
@@ -332,7 +332,7 @@ pub trait UnitTrait:
 
     fn extract_mop(
         &self,
-        mop: Expr<RenamedMOp<UnitOutRegNum<PhantomConst<CpuConfig>>, DynSize>>,
+        mop: Expr<RenamedMOp<UnitOutRegNum<DynSize>, DynSize>>,
     ) -> Expr<HdlOption<Self::MOp>>;
 
     fn module(&self) -> Interned<Module<Self::Type>>;
@@ -340,7 +340,7 @@ pub trait UnitTrait:
     fn unit_to_reg_alloc(
         &self,
         this: Expr<Self::Type>,
-    ) -> Expr<UnitToRegAlloc<PhantomConst<CpuConfig>, Self::MOp, Self::ExtraOut>>;
+    ) -> Expr<UnitToRegAlloc<Self::MOp, Self::ExtraOut, DynSize, DynSize, DynSize>>;
 
     fn cd(&self, this: Expr<Self::Type>) -> Expr<ClockDomain>;
 
@@ -390,7 +390,7 @@ impl UnitTrait for DynUnit {
 
     fn extract_mop(
         &self,
-        mop: Expr<RenamedMOp<UnitOutRegNum<PhantomConst<CpuConfig>>, DynSize>>,
+        mop: Expr<RenamedMOp<UnitOutRegNum<DynSize>, DynSize>>,
     ) -> Expr<HdlOption<Self::MOp>> {
         self.unit.extract_mop(mop)
     }
@@ -402,7 +402,7 @@ impl UnitTrait for DynUnit {
     fn unit_to_reg_alloc(
         &self,
         this: Expr<Self::Type>,
-    ) -> Expr<UnitToRegAlloc<PhantomConst<CpuConfig>, Self::MOp, Self::ExtraOut>> {
+    ) -> Expr<UnitToRegAlloc<Self::MOp, Self::ExtraOut, DynSize, DynSize, DynSize>> {
         self.unit.unit_to_reg_alloc(this)
     }
 
@@ -445,7 +445,7 @@ impl<T: UnitTrait + Clone + std::hash::Hash + Eq> UnitTrait for DynUnitWrapper<T
 
     fn extract_mop(
         &self,
-        mop: Expr<RenamedMOp<UnitOutRegNum<PhantomConst<CpuConfig>>, DynSize>>,
+        mop: Expr<RenamedMOp<UnitOutRegNum<DynSize>, DynSize>>,
     ) -> Expr<HdlOption<Self::MOp>> {
         Expr::from_enum(Expr::as_enum(self.0.extract_mop(mop)))
     }
@@ -457,7 +457,7 @@ impl<T: UnitTrait + Clone + std::hash::Hash + Eq> UnitTrait for DynUnitWrapper<T
     fn unit_to_reg_alloc(
         &self,
         this: Expr<Self::Type>,
-    ) -> Expr<UnitToRegAlloc<PhantomConst<CpuConfig>, Self::MOp, Self::ExtraOut>> {
+    ) -> Expr<UnitToRegAlloc<Self::MOp, Self::ExtraOut, DynSize, DynSize, DynSize>> {
         Expr::from_bundle(Expr::as_bundle(
             self.0.unit_to_reg_alloc(Expr::from_bundle(this)),
         ))
diff --git a/crates/cpu/src/unit/alu_branch.rs b/crates/cpu/src/unit/alu_branch.rs
index a86b43b..6815ae6 100644
--- a/crates/cpu/src/unit/alu_branch.rs
+++ b/crates/cpu/src/unit/alu_branch.rs
@@ -19,13 +19,16 @@ use crate::{
     },
 };
 use fayalite::{
-    intern::Interned, module::wire_with_loc, prelude::*, util::ready_valid::ReadyValid,
+    intern::{Intern, Interned},
+    module::wire_with_loc,
+    prelude::*,
+    util::ready_valid::ReadyValid,
 };
 use std::{collections::HashMap, ops::RangeTo};
 
 #[hdl]
 fn add_sub<SrcCount: KnownSize>(
-    mop: Expr<AddSubMOp<UnitOutRegNum<PhantomConst<CpuConfig>>, DynSize, SrcCount>>,
+    mop: Expr<AddSubMOp<UnitOutRegNum<DynSize>, DynSize, SrcCount>>,
     pc: Expr<UInt<64>>,
     flags_mode: Expr<FlagsMode>,
     src_values: Expr<Array<PRegValue, { COMMON_MOP_SRC_LEN }>>,
@@ -242,7 +245,7 @@ fn add_sub<SrcCount: KnownSize>(
 
 #[hdl]
 fn logical_flags(
-    mop: Expr<LogicalFlagsMOp<UnitOutRegNum<PhantomConst<CpuConfig>>, DynSize>>,
+    mop: Expr<LogicalFlagsMOp<UnitOutRegNum<DynSize>, DynSize>>,
     flags_mode: Expr<FlagsMode>,
     src_values: Expr<Array<PRegValue, { COMMON_MOP_SRC_LEN }>>,
 ) -> Expr<UnitResultCompleted<()>> {
@@ -256,7 +259,7 @@ fn logical_flags(
 
 #[hdl]
 fn logical(
-    mop: Expr<LogicalMOp<UnitOutRegNum<PhantomConst<CpuConfig>>, DynSize, ConstUsize<2>>>,
+    mop: Expr<LogicalMOp<UnitOutRegNum<DynSize>, DynSize, ConstUsize<2>>>,
     flags_mode: Expr<FlagsMode>,
     src_values: Expr<Array<PRegValue, { COMMON_MOP_SRC_LEN }>>,
 ) -> Expr<UnitResultCompleted<()>> {
@@ -270,7 +273,7 @@ fn logical(
 
 #[hdl]
 fn logical_i(
-    mop: Expr<LogicalMOp<UnitOutRegNum<PhantomConst<CpuConfig>>, DynSize, ConstUsize<1>>>,
+    mop: Expr<LogicalMOp<UnitOutRegNum<DynSize>, DynSize, ConstUsize<1>>>,
     flags_mode: Expr<FlagsMode>,
     src_values: Expr<Array<PRegValue, { COMMON_MOP_SRC_LEN }>>,
 ) -> Expr<UnitResultCompleted<()>> {
@@ -284,7 +287,7 @@ fn logical_i(
 
 #[hdl]
 fn shift_rotate(
-    mop: Expr<ShiftRotateMOp<UnitOutRegNum<PhantomConst<CpuConfig>>, DynSize>>,
+    mop: Expr<ShiftRotateMOp<UnitOutRegNum<DynSize>, DynSize>>,
     flags_mode: Expr<FlagsMode>,
     src_values: Expr<Array<PRegValue, { COMMON_MOP_SRC_LEN }>>,
 ) -> Expr<UnitResultCompleted<()>> {
@@ -298,7 +301,7 @@ fn shift_rotate(
 
 #[hdl]
 fn compare<SrcCount: KnownSize>(
-    mop: Expr<CompareMOp<UnitOutRegNum<PhantomConst<CpuConfig>>, DynSize, SrcCount>>,
+    mop: Expr<CompareMOp<UnitOutRegNum<DynSize>, DynSize, SrcCount>>,
     flags_mode: Expr<FlagsMode>,
     src_values: Expr<Array<PRegValue, { COMMON_MOP_SRC_LEN }>>,
 ) -> Expr<UnitResultCompleted<()>> {
@@ -312,7 +315,7 @@ fn compare<SrcCount: KnownSize>(
 
 #[hdl]
 fn branch<SrcCount: KnownSize>(
-    mop: Expr<BranchMOp<UnitOutRegNum<PhantomConst<CpuConfig>>, DynSize, SrcCount>>,
+    mop: Expr<BranchMOp<UnitOutRegNum<DynSize>, DynSize, SrcCount>>,
     pc: Expr<UInt<64>>,
     flags_mode: Expr<FlagsMode>,
     src_values: Expr<Array<PRegValue, { COMMON_MOP_SRC_LEN }>>,
@@ -327,7 +330,7 @@ fn branch<SrcCount: KnownSize>(
 
 #[hdl]
 fn read_special(
-    mop: Expr<ReadSpecialMOp<UnitOutRegNum<PhantomConst<CpuConfig>>, DynSize>>,
+    mop: Expr<ReadSpecialMOp<UnitOutRegNum<DynSize>, DynSize>>,
     pc: Expr<UInt<64>>,
     flags_mode: Expr<FlagsMode>,
     src_values: Expr<Array<PRegValue, { COMMON_MOP_SRC_LEN }>>,
@@ -341,18 +344,20 @@ fn read_special(
 }
 
 #[hdl_module]
-pub fn alu_branch(config: PhantomConst<CpuConfig>, unit_index: usize) {
+pub fn alu_branch(config: &CpuConfig, unit_index: usize) {
     #[hdl]
     let cd: ClockDomain = m.input();
     #[hdl]
     let unit_to_reg_alloc: UnitToRegAlloc<
-        PhantomConst<CpuConfig>,
-        AluBranchMOp<UnitOutRegNum<PhantomConst<CpuConfig>>, DynSize>,
+        AluBranchMOp<UnitOutRegNum<DynSize>, DynSize>,
         (),
-    > = m.output(
-        UnitToRegAlloc[config][AluBranchMOp[UnitOutRegNum[config]][config.get().p_reg_num_width()]]
-            [()],
-    );
+        DynSize,
+        DynSize,
+        DynSize,
+    > = m.output(config.unit_to_reg_alloc(
+        AluBranchMOp[config.unit_out_reg_num()][config.p_reg_num_width()],
+        (),
+    ));
     #[hdl]
     let global_state: GlobalState = m.input();
 
@@ -370,11 +375,10 @@ pub fn alu_branch(config: PhantomConst<CpuConfig>, unit_index: usize) {
     #[hdl]
     if let HdlSome(execute_start) = ReadyValid::firing_data(unit_base.execute_start) {
         #[hdl]
-        let ExecuteStart::<_, _> {
+        let ExecuteStart::<_> {
             mop,
             pc,
             src_values,
-            config: _,
         } = execute_start;
         #[hdl]
         match mop {
@@ -576,14 +580,14 @@ pub fn alu_branch(config: PhantomConst<CpuConfig>, unit_index: usize) {
 
 #[derive(Debug, Copy, Clone, PartialEq, Eq, Hash)]
 pub struct AluBranch {
-    config: PhantomConst<CpuConfig>,
+    config: Interned<CpuConfig>,
     module: Interned<Module<alu_branch>>,
 }
 
 impl AluBranch {
-    pub fn new(config: PhantomConst<CpuConfig>, unit_index: usize) -> Self {
+    pub fn new(config: &CpuConfig, unit_index: usize) -> Self {
         Self {
-            config,
+            config: config.intern(),
             module: alu_branch(config, unit_index),
         }
     }
@@ -592,7 +596,7 @@ impl AluBranch {
 impl UnitTrait for AluBranch {
     type Type = alu_branch;
     type ExtraOut = ();
-    type MOp = AluBranchMOp<UnitOutRegNum<PhantomConst<CpuConfig>>, DynSize>;
+    type MOp = AluBranchMOp<UnitOutRegNum<DynSize>, DynSize>;
 
     fn ty(&self) -> Self::Type {
         self.module.io_ty()
@@ -612,7 +616,7 @@ impl UnitTrait for AluBranch {
 
     fn extract_mop(
         &self,
-        mop: Expr<RenamedMOp<UnitOutRegNum<PhantomConst<CpuConfig>>, DynSize>>,
+        mop: Expr<RenamedMOp<UnitOutRegNum<DynSize>, DynSize>>,
     ) -> Expr<HdlOption<Self::MOp>> {
         UnitMOp::alu_branch_mop(mop)
     }
@@ -624,7 +628,7 @@ impl UnitTrait for AluBranch {
     fn unit_to_reg_alloc(
         &self,
         this: Expr<Self::Type>,
-    ) -> Expr<UnitToRegAlloc<PhantomConst<CpuConfig>, Self::MOp, Self::ExtraOut>> {
+    ) -> Expr<UnitToRegAlloc<Self::MOp, Self::ExtraOut, DynSize, DynSize, DynSize>> {
         this.unit_to_reg_alloc
     }
 
diff --git a/crates/cpu/src/unit/unit_base.rs b/crates/cpu/src/unit/unit_base.rs
index cc7c754..4e665e0 100644
--- a/crates/cpu/src/unit/unit_base.rs
+++ b/crates/cpu/src/unit/unit_base.rs
@@ -2,7 +2,7 @@
 // See Notices.txt for copyright information
 
 use crate::{
-    config::{CpuConfig, CpuConfigUnitCount, PhantomConstCpuConfig},
+    config::CpuConfig,
     instruction::{COMMON_MOP_SRC_LEN, MOpTrait, PRegNum, UnitNum, UnitOutRegNum},
     register::PRegValue,
     unit::{UnitCancelInput, UnitOutput, UnitOutputWrite},
@@ -15,11 +15,13 @@ use fayalite::{
     ty::StaticType,
     util::ready_valid::ReadyValid,
 };
+use std::marker::PhantomData;
 
-#[hdl(no_static)]
-pub struct UnitForwardingInfo<C: PhantomConstGet<CpuConfig>> {
-    pub unit_output_writes: ArrayType<HdlOption<UnitOutputWrite<C>>, CpuConfigUnitCount<C>>,
-    pub unit_reg_frees: ArrayType<HdlOption<UnitOutRegNum<C>>, CpuConfigUnitCount<C>>,
+#[hdl]
+pub struct UnitForwardingInfo<UnitNumWidth: Size, OutRegNumWidth: Size, UnitCount: Size> {
+    pub unit_output_writes: ArrayType<HdlOption<UnitOutputWrite<OutRegNumWidth>>, UnitCount>,
+    pub unit_reg_frees: ArrayType<HdlOption<UnitOutRegNum<OutRegNumWidth>>, UnitCount>,
+    pub _phantom: PhantomData<UnitNumWidth>,
 }
 
 #[hdl]
@@ -28,18 +30,26 @@ pub struct UnitInput<MOp: Type> {
     pub pc: UInt<64>,
 }
 
-#[hdl(no_static)]
-pub struct UnitToRegAlloc<C: PhantomConstGet<CpuConfig>, MOp: Type, ExtraOut: Type> {
+#[hdl]
+pub struct UnitToRegAlloc<
+    MOp: Type,
+    ExtraOut: Type,
+    UnitNumWidth: Size,
+    OutRegNumWidth: Size,
+    UnitCount: Size,
+> {
     #[hdl(flip)]
-    pub unit_forwarding_info: UnitForwardingInfo<C>,
+    pub unit_forwarding_info: UnitForwardingInfo<UnitNumWidth, OutRegNumWidth, UnitCount>,
     #[hdl(flip)]
     pub input: ReadyValid<UnitInput<MOp>>,
     #[hdl(flip)]
-    pub cancel_input: HdlOption<UnitCancelInput<C>>,
-    pub output: HdlOption<UnitOutput<C, ExtraOut>>,
+    pub cancel_input: HdlOption<UnitCancelInput<OutRegNumWidth>>,
+    pub output: HdlOption<UnitOutput<OutRegNumWidth, ExtraOut>>,
 }
 
-impl<C: PhantomConstCpuConfig, MOp: Type, ExtraOut: Type> UnitToRegAlloc<C, MOp, ExtraOut> {
+impl<MOp: Type, ExtraOut: Type, UnitNumWidth: Size, OutRegNumWidth: Size, UnitCount: Size>
+    UnitToRegAlloc<MOp, ExtraOut, UnitNumWidth, OutRegNumWidth, UnitCount>
+{
     pub fn mop_ty(self) -> MOp {
         self.input.data.HdlSome.mop
     }
@@ -48,20 +58,16 @@ impl<C: PhantomConstCpuConfig, MOp: Type, ExtraOut: Type> UnitToRegAlloc<C, MOp,
     }
 }
 
-#[hdl(no_static)]
-pub struct ExecuteStart<
-    C: PhantomConstGet<CpuConfig>,
-    MOp: Type + MOpTrait<DestReg = UnitOutRegNum<C>>,
-> {
+#[hdl]
+pub struct ExecuteStart<MOp: Type + MOpTrait<DestReg = UnitOutRegNum<DynSize>>> {
     pub mop: MOp,
     pub pc: UInt<64>,
     pub src_values: Array<PRegValue, { COMMON_MOP_SRC_LEN }>,
-    pub config: C,
 }
 
-#[hdl(no_static)]
-pub struct ExecuteEnd<C: PhantomConstGet<CpuConfig>, ExtraOut> {
-    pub unit_output: UnitOutput<C, ExtraOut>,
+#[hdl]
+pub struct ExecuteEnd<OutRegNumWidth: Size, ExtraOut> {
+    pub unit_output: UnitOutput<OutRegNumWidth, ExtraOut>,
 }
 
 #[hdl]
@@ -234,10 +240,10 @@ impl InFlightOpsSummary<DynSize> {
 
 #[hdl_module]
 pub fn unit_base<
-    MOp: Type + MOpTrait<DestReg = UnitOutRegNum<PhantomConst<CpuConfig>>, SrcRegWidth = DynSize>,
+    MOp: Type + MOpTrait<DestReg = UnitOutRegNum<DynSize>, SrcRegWidth = DynSize>,
     ExtraOut: Type,
 >(
-    config: PhantomConst<CpuConfig>,
+    config: &CpuConfig,
     unit_index: usize,
     mop_ty: MOp,
     extra_out_ty: ExtraOut,
@@ -245,18 +251,17 @@ pub fn unit_base<
     #[hdl]
     let cd: ClockDomain = m.input();
     #[hdl]
-    let unit_to_reg_alloc: UnitToRegAlloc<PhantomConst<CpuConfig>, MOp, ExtraOut> =
-        m.output(UnitToRegAlloc[config][mop_ty][extra_out_ty]);
+    let unit_to_reg_alloc: UnitToRegAlloc<MOp, ExtraOut, DynSize, DynSize, DynSize> =
+        m.output(config.unit_to_reg_alloc(mop_ty, extra_out_ty));
     #[hdl]
-    let execute_start: ReadyValid<ExecuteStart<PhantomConst<CpuConfig>, MOp>> =
-        m.output(ReadyValid[ExecuteStart[config][mop_ty]]);
+    let execute_start: ReadyValid<ExecuteStart<MOp>> = m.output(ReadyValid[ExecuteStart[mop_ty]]);
     #[hdl]
-    let execute_end: HdlOption<ExecuteEnd<PhantomConst<CpuConfig>, ExtraOut>> =
-        m.input(HdlOption[ExecuteEnd[config][extra_out_ty]]);
+    let execute_end: HdlOption<ExecuteEnd<DynSize, ExtraOut>> =
+        m.input(HdlOption[ExecuteEnd[config.out_reg_num_width][extra_out_ty]]);
 
     connect(execute_start.data, execute_start.ty().data.HdlNone());
 
-    let max_in_flight = config.get().unit_max_in_flight(unit_index).get();
+    let max_in_flight = config.unit_max_in_flight(unit_index).get();
     let in_flight_op_ty = InFlightOp[mop_ty];
     #[hdl]
     let in_flight_ops = reg_builder()
@@ -274,15 +279,16 @@ pub fn unit_base<
     );
 
     #[hdl]
-    let UnitForwardingInfo::<_> {
+    let UnitForwardingInfo::<_, _, _> {
         unit_output_writes,
         unit_reg_frees,
+        _phantom: _,
     } = unit_to_reg_alloc.unit_forwarding_info;
     #[hdl]
     let read_src_regs = wire(mop_ty.src_regs_ty());
     connect(
         read_src_regs,
-        repeat(PRegNum[config].const_zero().cast_to_bits(), ConstUsize),
+        repeat(config.p_reg_num().const_zero().cast_to_bits(), ConstUsize),
     );
     #[hdl]
     let read_src_values = wire();
@@ -291,7 +297,7 @@ pub fn unit_base<
     let input_src_regs = wire(mop_ty.src_regs_ty());
     connect(
         input_src_regs,
-        repeat(PRegNum[config].const_zero().cast_to_bits(), ConstUsize),
+        repeat(config.p_reg_num().const_zero().cast_to_bits(), ConstUsize),
     );
     #[hdl]
     let input_src_regs_valid = wire();
@@ -303,7 +309,7 @@ pub fn unit_base<
                 Bool,
                 SourceLocation::caller(),
             );
-            mem.depth(1 << config.get().out_reg_num_width);
+            mem.depth(1 << config.out_reg_num_width);
             mem
         })
         .collect();
@@ -313,11 +319,11 @@ pub fn unit_base<
             PRegValue,
             SourceLocation::caller(),
         );
-        unit_output_regs.depth(1 << config.get().out_reg_num_width);
+        unit_output_regs.depth(1 << config.out_reg_num_width);
 
         for src_index in 0..COMMON_MOP_SRC_LEN {
             let read_port = unit_output_regs.new_read_port();
-            let p_reg_num = read_src_regs[src_index].cast_bits_to(PRegNum[config]);
+            let p_reg_num = read_src_regs[src_index].cast_bits_to(config.p_reg_num());
             connect_any(read_port.addr, p_reg_num.unit_out_reg.value);
             connect(read_port.en, false);
             connect(read_port.clk, cd.clk);
@@ -330,7 +336,7 @@ pub fn unit_base<
 
         for src_index in 0..COMMON_MOP_SRC_LEN {
             let read_port = unit_output_regs_valid[unit_index].new_read_port();
-            let p_reg_num = input_src_regs[src_index].cast_bits_to(PRegNum[config]);
+            let p_reg_num = input_src_regs[src_index].cast_bits_to(config.p_reg_num());
             connect_any(read_port.addr, p_reg_num.unit_out_reg.value);
             connect(read_port.en, false);
             connect(read_port.clk, cd.clk);
@@ -361,8 +367,8 @@ pub fn unit_base<
             connect_any(ready_write_port.addr, unit_output_write.which.value);
             connect(ready_write_port.en, true);
             let p_reg_num = #[hdl]
-            PRegNum::<_> {
-                unit_num: UnitNum[config].from_index(unit_index),
+            PRegNum::<_, _> {
+                unit_num: config.unit_num().from_index(unit_index),
                 unit_out_reg: unit_output_write.which,
             };
             for src_index in 0..COMMON_MOP_SRC_LEN {
@@ -393,11 +399,10 @@ pub fn unit_base<
                 execute_start.data,
                 HdlSome(
                     #[hdl]
-                    ExecuteStart::<_, _> {
+                    ExecuteStart::<_> {
                         mop: in_flight_op.mop,
                         pc: in_flight_op.pc,
                         src_values: read_src_values,
-                        config,
                     },
                 ),
             );
@@ -420,7 +425,7 @@ pub fn unit_base<
         let input_mop_src_regs = wire(mop_ty.src_regs_ty());
         connect(
             input_mop_src_regs,
-            repeat(PRegNum[config].const_zero().cast_to_bits(), ConstUsize),
+            repeat(config.p_reg_num().const_zero().cast_to_bits(), ConstUsize),
         );
         MOp::connect_src_regs(mop, input_mop_src_regs);
         let src_ready_flags = wire_with_loc(
@@ -492,7 +497,7 @@ pub fn unit_base<
             );
             connect(
                 src_regs,
-                repeat(PRegNum[config].const_zero().cast_to_bits(), ConstUsize),
+                repeat(config.p_reg_num().const_zero().cast_to_bits(), ConstUsize),
             );
             MOp::connect_src_regs(mop, src_regs);
 
@@ -516,8 +521,8 @@ pub fn unit_base<
                         value: _,
                     } = unit_output_write;
                     let p_reg_num = #[hdl]
-                    PRegNum::<_> {
-                        unit_num: UnitNum[config].from_index(unit_index),
+                    PRegNum::<_, _> {
+                        unit_num: config.unit_num().from_index(unit_index),
                         unit_out_reg,
                     };
                     for src_index in 0..COMMON_MOP_SRC_LEN {