Auto merge of #127087 - cjgillot:small-map, r=oli-obk

Only track mentioned places for jump threading

This PR aims to reduce the state space size in jump threading and dataflow const-prop opts.

The current implementation walks the types of all locals, and creates a place for each possible projection. This can easily lead to a large number of places and tracked values, most being useless to the actual pass.

With this PR, we instead collect places that appear syntactically in the MIR (first commit). However, this is not sufficient (second commit), and we miss places that we could track in aggregate assignments. The third commit tracks such assignments to mirror place projections, see the inline comment.

This is complementary to #127036

r? `@oli-obk`

Author: bors

compiler/rustc_mir_dataflow/src/value_analysis.rs

@@ -66,7 +66,7 @@ impl<'tcx> MirPass<'tcx> for DataflowConstProp {
 }
 
 struct ConstAnalysis<'a, 'tcx> {
-    map: Map,
+    map: Map<'tcx>,
     tcx: TyCtxt<'tcx>,
     local_decls: &'a LocalDecls<'tcx>,
     ecx: InterpCx<'tcx, DummyMachine>,
@@ -78,7 +78,7 @@ impl<'tcx> ValueAnalysis<'tcx> for ConstAnalysis<'_, 'tcx> {
 
     const NAME: &'static str = "ConstAnalysis";
 
-    fn map(&self) -> &Map {
+    fn map(&self) -> &Map<'tcx> {
         &self.map
     }
 
@@ -330,7 +330,7 @@ impl<'tcx> ValueAnalysis<'tcx> for ConstAnalysis<'_, 'tcx> {
 }
 
 impl<'a, 'tcx> ConstAnalysis<'a, 'tcx> {
-    pub fn new(tcx: TyCtxt<'tcx>, body: &'a Body<'tcx>, map: Map) -> Self {
+    pub fn new(tcx: TyCtxt<'tcx>, body: &'a Body<'tcx>, map: Map<'tcx>) -> Self {
         let param_env = tcx.param_env_reveal_all_normalized(body.source.def_id());
         Self {
             map,
@@ -560,12 +560,13 @@ impl<'tcx, 'locals> Collector<'tcx, 'locals> {
         Self { patch: Patch::new(tcx), local_decls }
     }
 
+    #[instrument(level = "trace", skip(self, ecx, map), ret)]
     fn try_make_constant(
         &self,
         ecx: &mut InterpCx<'tcx, DummyMachine>,
         place: Place<'tcx>,
         state: &State<FlatSet<Scalar>>,
-        map: &Map,
+        map: &Map<'tcx>,
     ) -> Option<Const<'tcx>> {
         let ty = place.ty(self.local_decls, self.patch.tcx).ty;
         let layout = ecx.layout_of(ty).ok()?;
@@ -598,10 +599,11 @@ impl<'tcx, 'locals> Collector<'tcx, 'locals> {
     }
 }
 
+#[instrument(level = "trace", skip(map), ret)]
 fn propagatable_scalar(
     place: PlaceIndex,
     state: &State<FlatSet<Scalar>>,
-    map: &Map,
+    map: &Map<'_>,
 ) -> Option<Scalar> {
     if let FlatSet::Elem(value) = state.get_idx(place, map)
         && value.try_to_scalar_int().is_ok()
@@ -613,14 +615,14 @@ fn propagatable_scalar(
     }
 }
 
-#[instrument(level = "trace", skip(ecx, state, map))]
+#[instrument(level = "trace", skip(ecx, state, map), ret)]
 fn try_write_constant<'tcx>(
     ecx: &mut InterpCx<'tcx, DummyMachine>,
     dest: &PlaceTy<'tcx>,
     place: PlaceIndex,
     ty: Ty<'tcx>,
     state: &State<FlatSet<Scalar>>,
-    map: &Map,
+    map: &Map<'tcx>,
 ) -> InterpResult<'tcx> {
     let layout = ecx.layout_of(ty)?;
 
@@ -719,6 +721,7 @@ impl<'mir, 'tcx>
 {
     type FlowState = State<FlatSet<Scalar>>;
 
+    #[instrument(level = "trace", skip(self, results, statement))]
     fn visit_statement_before_primary_effect(
         &mut self,
         results: &mut Results<'tcx, ValueAnalysisWrapper<ConstAnalysis<'_, 'tcx>>>,
@@ -740,6 +743,7 @@ impl<'mir, 'tcx>
         }
     }
 
+    #[instrument(level = "trace", skip(self, results, statement))]
     fn visit_statement_after_primary_effect(
         &mut self,
         results: &mut Results<'tcx, ValueAnalysisWrapper<ConstAnalysis<'_, 'tcx>>>,
@@ -834,7 +838,7 @@ struct OperandCollector<'tcx, 'map, 'locals, 'a> {
     state: &'a State<FlatSet<Scalar>>,
     visitor: &'a mut Collector<'tcx, 'locals>,
     ecx: &'map mut InterpCx<'tcx, DummyMachine>,
-    map: &'map Map,
+    map: &'map Map<'tcx>,
 }
 
 impl<'tcx> Visitor<'tcx> for OperandCollector<'tcx, '_, '_, '_> {

compiler/rustc_mir_transform/src/dataflow_const_prop.rs

@@ -123,7 +123,7 @@ struct TOFinder<'tcx, 'a> {
     param_env: ty::ParamEnv<'tcx>,
     ecx: InterpCx<'tcx, DummyMachine>,
     body: &'a Body<'tcx>,
-    map: &'a Map,
+    map: &'a Map<'tcx>,
     loop_headers: &'a BitSet<BasicBlock>,
     /// We use an arena to avoid cloning the slices when cloning `state`.
     arena: &'a DroplessArena,

compiler/rustc_mir_transform/src/jump_threading.rs

@@ -31,16 +31,18 @@ Number of file 0 mappings: 24
     = (c0 - c1)
 - Code(Counter(0)) at (prev + 1, 5) to (start + 3, 2)
 
-Function name: closure::main::{closure#0} (unused)
-Raw bytes (24): 0x[01, 01, 00, 04, 00, 28, 05, 02, 14, 00, 02, 15, 02, 0a, 00, 02, 0a, 00, 0b, 00, 01, 09, 01, 06]
+Function name: closure::main::{closure#0}
+Raw bytes (26): 0x[01, 01, 01, 01, 05, 04, 01, 28, 05, 02, 14, 05, 02, 15, 02, 0a, 02, 02, 0a, 00, 0b, 01, 01, 09, 01, 06]
 Number of files: 1
 - file 0 => global file 1
-Number of expressions: 0
+Number of expressions: 1
+- expression 0 operands: lhs = Counter(0), rhs = Counter(1)
 Number of file 0 mappings: 4
-- Code(Zero) at (prev + 40, 5) to (start + 2, 20)
-- Code(Zero) at (prev + 2, 21) to (start + 2, 10)
-- Code(Zero) at (prev + 2, 10) to (start + 0, 11)
-- Code(Zero) at (prev + 1, 9) to (start + 1, 6)
+- Code(Counter(0)) at (prev + 40, 5) to (start + 2, 20)
+- Code(Counter(1)) at (prev + 2, 21) to (start + 2, 10)
+- Code(Expression(0, Sub)) at (prev + 2, 10) to (start + 0, 11)
+    = (c0 - c1)
+- Code(Counter(0)) at (prev + 1, 9) to (start + 1, 6)
 
 Function name: closure::main::{closure#10} (unused)
 Raw bytes (10): 0x[01, 01, 00, 01, 00, 9b, 01, 07, 00, 21]

tests/coverage/closure.cov-map

@@ -81,101 +81,130 @@ Number of file 0 mappings: 11
     = (((c4 + Zero) + Zero) + c3)
 
 Function name: try_error_result::test2
-Raw bytes (280): 0x[01, 01, 24, 01, 07, 00, 09, 03, 0d, 41, 00, 1e, 00, 41, 00, 1e, 00, 41, 00, 4a, 00, 4e, 00, 52, 41, 03, 0d, 52, 41, 03, 0d, 4e, 00, 52, 41, 03, 0d, 4a, 00, 4e, 00, 52, 41, 03, 0d, 66, 00, 45, 00, 45, 00, 66, 00, 45, 00, 7a, 00, 4d, 00, 4d, 00, 7a, 00, 4d, 00, 83, 01, 0d, 87, 01, 00, 00, 8b, 01, 8f, 01, 00, 19, 00, 28, 01, 3d, 01, 03, 17, 03, 08, 09, 00, 0e, 52, 02, 09, 04, 1a, 41, 06, 0d, 00, 2f, 00, 00, 2f, 00, 30, 1e, 00, 31, 03, 35, 00, 04, 11, 00, 12, 1a, 02, 11, 04, 12, 00, 05, 11, 00, 14, 1a, 00, 17, 00, 41, 19, 00, 41, 00, 42, 00, 00, 43, 00, 5f, 00, 00, 5f, 00, 60, 00, 01, 0d, 00, 20, 00, 01, 11, 00, 14, 00, 00, 17, 00, 41, 00, 00, 41, 00, 42, 00, 00, 43, 00, 60, 00, 00, 60, 00, 61, 00, 01, 0d, 00, 20, 46, 04, 11, 00, 14, 4e, 00, 17, 00, 42, 00, 00, 42, 00, 43, 4a, 00, 44, 00, 61, 00, 00, 61, 00, 62, 46, 01, 0d, 00, 20, 62, 01, 11, 00, 14, 45, 00, 17, 01, 36, 00, 01, 36, 00, 37, 66, 01, 12, 00, 2f, 00, 00, 2f, 00, 30, 62, 01, 0d, 00, 20, 76, 01, 11, 00, 14, 4d, 00, 17, 01, 36, 00, 02, 11, 00, 12, 7a, 01, 12, 00, 2f, 00, 01, 11, 00, 12, 76, 02, 0d, 00, 20, 0d, 03, 05, 00, 0b, 7f, 01, 01, 00, 02]
+Raw bytes (358): 0x[01, 01, 3b, 01, 07, 05, 09, 03, 0d, 41, 11, 4a, 15, 41, 11, 42, 1d, 46, 19, 4a, 15, 41, 11, 4a, 15, 41, 11, 46, 19, 4a, 15, 41, 11, 42, 1d, 46, 19, 4a, 15, 41, 11, 5e, 25, 49, 21, 49, 21, 5e, 25, 49, 21, 8a, 01, 2d, 8e, 01, 29, 92, 01, 41, 03, 0d, 92, 01, 41, 03, 0d, 8e, 01, 29, 92, 01, 41, 03, 0d, 8a, 01, 2d, 8e, 01, 29, 92, 01, 41, 03, 0d, a6, 01, 35, 45, 31, 45, 31, a6, 01, 35, 45, 31, ba, 01, 3d, 4d, 39, 4d, 39, ba, 01, 3d, 4d, 39, c3, 01, 0d, c7, 01, db, 01, cb, 01, cf, 01, 11, 15, d3, 01, d7, 01, 19, 1d, 21, 25, df, 01, e3, 01, 29, 2d, e7, 01, eb, 01, 31, 35, 39, 3d, 28, 01, 3d, 01, 03, 17, 03, 08, 09, 00, 0e, 92, 01, 02, 09, 04, 1a, 41, 06, 0d, 00, 2f, 11, 00, 2f, 00, 30, 4a, 00, 31, 03, 35, 15, 04, 11, 00, 12, 46, 02, 11, 04, 12, 3e, 05, 11, 00, 14, 46, 00, 17, 00, 41, 19, 00, 41, 00, 42, 42, 00, 43, 00, 5f, 1d, 00, 5f, 00, 60, 3e, 01, 0d, 00, 20, 5a, 01, 11, 00, 14, 49, 00, 17, 00, 41, 21, 00, 41, 00, 42, 5e, 00, 43, 00, 60, 25, 00, 60, 00, 61, 5a, 01, 0d, 00, 20, 86, 01, 04, 11, 00, 14, 8e, 01, 00, 17, 00, 42, 29, 00, 42, 00, 43, 8a, 01, 00, 44, 00, 61, 2d, 00, 61, 00, 62, 86, 01, 01, 0d, 00, 20, a2, 01, 01, 11, 00, 14, 45, 00, 17, 01, 36, 31, 01, 36, 00, 37, a6, 01, 01, 12, 00, 2f, 35, 00, 2f, 00, 30, a2, 01, 01, 0d, 00, 20, b6, 01, 01, 11, 00, 14, 4d, 00, 17, 01, 36, 39, 02, 11, 00, 12, ba, 01, 01, 12, 00, 2f, 3d, 01, 11, 00, 12, b6, 01, 02, 0d, 00, 20, 0d, 03, 05, 00, 0b, bf, 01, 01, 01, 00, 02]
 Number of files: 1
 - file 0 => global file 1
-Number of expressions: 36
+Number of expressions: 59
 - expression 0 operands: lhs = Counter(0), rhs = Expression(1, Add)
-- expression 1 operands: lhs = Zero, rhs = Counter(2)
+- expression 1 operands: lhs = Counter(1), rhs = Counter(2)
 - expression 2 operands: lhs = Expression(0, Add), rhs = Counter(3)
-- expression 3 operands: lhs = Counter(16), rhs = Zero
-- expression 4 operands: lhs = Expression(7, Sub), rhs = Zero
-- expression 5 operands: lhs = Counter(16), rhs = Zero
-- expression 6 operands: lhs = Expression(7, Sub), rhs = Zero
-- expression 7 operands: lhs = Counter(16), rhs = Zero
-- expression 8 operands: lhs = Expression(18, Sub), rhs = Zero
-- expression 9 operands: lhs = Expression(19, Sub), rhs = Zero
-- expression 10 operands: lhs = Expression(20, Sub), rhs = Counter(16)
-- expression 11 operands: lhs = Expression(0, Add), rhs = Counter(3)
-- expression 12 operands: lhs = Expression(20, Sub), rhs = Counter(16)
-- expression 13 operands: lhs = Expression(0, Add), rhs = Counter(3)
-- expression 14 operands: lhs = Expression(19, Sub), rhs = Zero
-- expression 15 operands: lhs = Expression(20, Sub), rhs = Counter(16)
-- expression 16 operands: lhs = Expression(0, Add), rhs = Counter(3)
-- expression 17 operands: lhs = Expression(18, Sub), rhs = Zero
-- expression 18 operands: lhs = Expression(19, Sub), rhs = Zero
-- expression 19 operands: lhs = Expression(20, Sub), rhs = Counter(16)
-- expression 20 operands: lhs = Expression(0, Add), rhs = Counter(3)
-- expression 21 operands: lhs = Expression(25, Sub), rhs = Zero
-- expression 22 operands: lhs = Counter(17), rhs = Zero
-- expression 23 operands: lhs = Counter(17), rhs = Zero
-- expression 24 operands: lhs = Expression(25, Sub), rhs = Zero
-- expression 25 operands: lhs = Counter(17), rhs = Zero
-- expression 26 operands: lhs = Expression(30, Sub), rhs = Zero
-- expression 27 operands: lhs = Counter(19), rhs = Zero
-- expression 28 operands: lhs = Counter(19), rhs = Zero
-- expression 29 operands: lhs = Expression(30, Sub), rhs = Zero
-- expression 30 operands: lhs = Counter(19), rhs = Zero
-- expression 31 operands: lhs = Expression(32, Add), rhs = Counter(3)
-- expression 32 operands: lhs = Expression(33, Add), rhs = Zero
-- expression 33 operands: lhs = Zero, rhs = Expression(34, Add)
-- expression 34 operands: lhs = Expression(35, Add), rhs = Zero
-- expression 35 operands: lhs = Counter(6), rhs = Zero
+- expression 3 operands: lhs = Counter(16), rhs = Counter(4)
+- expression 4 operands: lhs = Expression(18, Sub), rhs = Counter(5)
+- expression 5 operands: lhs = Counter(16), rhs = Counter(4)
+- expression 6 operands: lhs = Expression(16, Sub), rhs = Counter(7)
+- expression 7 operands: lhs = Expression(17, Sub), rhs = Counter(6)
+- expression 8 operands: lhs = Expression(18, Sub), rhs = Counter(5)
+- expression 9 operands: lhs = Counter(16), rhs = Counter(4)
+- expression 10 operands: lhs = Expression(18, Sub), rhs = Counter(5)
+- expression 11 operands: lhs = Counter(16), rhs = Counter(4)
+- expression 12 operands: lhs = Expression(17, Sub), rhs = Counter(6)
+- expression 13 operands: lhs = Expression(18, Sub), rhs = Counter(5)
+- expression 14 operands: lhs = Counter(16), rhs = Counter(4)
+- expression 15 operands: lhs = Expression(16, Sub), rhs = Counter(7)
+- expression 16 operands: lhs = Expression(17, Sub), rhs = Counter(6)
+- expression 17 operands: lhs = Expression(18, Sub), rhs = Counter(5)
+- expression 18 operands: lhs = Counter(16), rhs = Counter(4)
+- expression 19 operands: lhs = Expression(23, Sub), rhs = Counter(9)
+- expression 20 operands: lhs = Counter(18), rhs = Counter(8)
+- expression 21 operands: lhs = Counter(18), rhs = Counter(8)
+- expression 22 operands: lhs = Expression(23, Sub), rhs = Counter(9)
+- expression 23 operands: lhs = Counter(18), rhs = Counter(8)
+- expression 24 operands: lhs = Expression(34, Sub), rhs = Counter(11)
+- expression 25 operands: lhs = Expression(35, Sub), rhs = Counter(10)
+- expression 26 operands: lhs = Expression(36, Sub), rhs = Counter(16)
+- expression 27 operands: lhs = Expression(0, Add), rhs = Counter(3)
+- expression 28 operands: lhs = Expression(36, Sub), rhs = Counter(16)
+- expression 29 operands: lhs = Expression(0, Add), rhs = Counter(3)
+- expression 30 operands: lhs = Expression(35, Sub), rhs = Counter(10)
+- expression 31 operands: lhs = Expression(36, Sub), rhs = Counter(16)
+- expression 32 operands: lhs = Expression(0, Add), rhs = Counter(3)
+- expression 33 operands: lhs = Expression(34, Sub), rhs = Counter(11)
+- expression 34 operands: lhs = Expression(35, Sub), rhs = Counter(10)
+- expression 35 operands: lhs = Expression(36, Sub), rhs = Counter(16)
+- expression 36 operands: lhs = Expression(0, Add), rhs = Counter(3)
+- expression 37 operands: lhs = Expression(41, Sub), rhs = Counter(13)
+- expression 38 operands: lhs = Counter(17), rhs = Counter(12)
+- expression 39 operands: lhs = Counter(17), rhs = Counter(12)
+- expression 40 operands: lhs = Expression(41, Sub), rhs = Counter(13)
+- expression 41 operands: lhs = Counter(17), rhs = Counter(12)
+- expression 42 operands: lhs = Expression(46, Sub), rhs = Counter(15)
+- expression 43 operands: lhs = Counter(19), rhs = Counter(14)
+- expression 44 operands: lhs = Counter(19), rhs = Counter(14)
+- expression 45 operands: lhs = Expression(46, Sub), rhs = Counter(15)
+- expression 46 operands: lhs = Counter(19), rhs = Counter(14)
+- expression 47 operands: lhs = Expression(48, Add), rhs = Counter(3)
+- expression 48 operands: lhs = Expression(49, Add), rhs = Expression(54, Add)
+- expression 49 operands: lhs = Expression(50, Add), rhs = Expression(51, Add)
+- expression 50 operands: lhs = Counter(4), rhs = Counter(5)
+- expression 51 operands: lhs = Expression(52, Add), rhs = Expression(53, Add)
+- expression 52 operands: lhs = Counter(6), rhs = Counter(7)
+- expression 53 operands: lhs = Counter(8), rhs = Counter(9)
+- expression 54 operands: lhs = Expression(55, Add), rhs = Expression(56, Add)
+- expression 55 operands: lhs = Counter(10), rhs = Counter(11)
+- expression 56 operands: lhs = Expression(57, Add), rhs = Expression(58, Add)
+- expression 57 operands: lhs = Counter(12), rhs = Counter(13)
+- expression 58 operands: lhs = Counter(14), rhs = Counter(15)
 Number of file 0 mappings: 40
 - Code(Counter(0)) at (prev + 61, 1) to (start + 3, 23)
 - Code(Expression(0, Add)) at (prev + 8, 9) to (start + 0, 14)
-    = (c0 + (Zero + c2))
-- Code(Expression(20, Sub)) at (prev + 2, 9) to (start + 4, 26)
-    = ((c0 + (Zero + c2)) - c3)
+    = (c0 + (c1 + c2))
+- Code(Expression(36, Sub)) at (prev + 2, 9) to (start + 4, 26)
+    = ((c0 + (c1 + c2)) - c3)
 - Code(Counter(16)) at (prev + 6, 13) to (start + 0, 47)
-- Code(Zero) at (prev + 0, 47) to (start + 0, 48)
-- Code(Expression(7, Sub)) at (prev + 0, 49) to (start + 3, 53)
-    = (c16 - Zero)
-- Code(Zero) at (prev + 4, 17) to (start + 0, 18)
-- Code(Expression(6, Sub)) at (prev + 2, 17) to (start + 4, 18)
-    = ((c16 - Zero) - Zero)
-- Code(Zero) at (prev + 5, 17) to (start + 0, 20)
-- Code(Expression(6, Sub)) at (prev + 0, 23) to (start + 0, 65)
-    = ((c16 - Zero) - Zero)
+- Code(Counter(4)) at (prev + 0, 47) to (start + 0, 48)
+- Code(Expression(18, Sub)) at (prev + 0, 49) to (start + 3, 53)
+    = (c16 - c4)
+- Code(Counter(5)) at (prev + 4, 17) to (start + 0, 18)
+- Code(Expression(17, Sub)) at (prev + 2, 17) to (start + 4, 18)
+    = ((c16 - c4) - c5)
+- Code(Expression(15, Sub)) at (prev + 5, 17) to (start + 0, 20)
+    = ((((c16 - c4) - c5) - c6) - c7)
+- Code(Expression(17, Sub)) at (prev + 0, 23) to (start + 0, 65)
+    = ((c16 - c4) - c5)
 - Code(Counter(6)) at (prev + 0, 65) to (start + 0, 66)
-- Code(Zero) at (prev + 0, 67) to (start + 0, 95)
-- Code(Zero) at (prev + 0, 95) to (start + 0, 96)
-- Code(Zero) at (prev + 1, 13) to (start + 0, 32)
-- Code(Zero) at (prev + 1, 17) to (start + 0, 20)
-- Code(Zero) at (prev + 0, 23) to (start + 0, 65)
-- Code(Zero) at (prev + 0, 65) to (start + 0, 66)
-- Code(Zero) at (prev + 0, 67) to (start + 0, 96)
-- Code(Zero) at (prev + 0, 96) to (start + 0, 97)
-- Code(Zero) at (prev + 1, 13) to (start + 0, 32)
-- Code(Expression(17, Sub)) at (prev + 4, 17) to (start + 0, 20)
-    = (((((c0 + (Zero + c2)) - c3) - c16) - Zero) - Zero)
-- Code(Expression(19, Sub)) at (prev + 0, 23) to (start + 0, 66)
-    = (((c0 + (Zero + c2)) - c3) - c16)
-- Code(Zero) at (prev + 0, 66) to (start + 0, 67)
-- Code(Expression(18, Sub)) at (prev + 0, 68) to (start + 0, 97)
-    = ((((c0 + (Zero + c2)) - c3) - c16) - Zero)
-- Code(Zero) at (prev + 0, 97) to (start + 0, 98)
-- Code(Expression(17, Sub)) at (prev + 1, 13) to (start + 0, 32)
-    = (((((c0 + (Zero + c2)) - c3) - c16) - Zero) - Zero)
-- Code(Expression(24, Sub)) at (prev + 1, 17) to (start + 0, 20)
-    = ((c17 - Zero) - Zero)
+- Code(Expression(16, Sub)) at (prev + 0, 67) to (start + 0, 95)
+    = (((c16 - c4) - c5) - c6)
+- Code(Counter(7)) at (prev + 0, 95) to (start + 0, 96)
+- Code(Expression(15, Sub)) at (prev + 1, 13) to (start + 0, 32)
+    = ((((c16 - c4) - c5) - c6) - c7)
+- Code(Expression(22, Sub)) at (prev + 1, 17) to (start + 0, 20)
+    = ((c18 - c8) - c9)
+- Code(Counter(18)) at (prev + 0, 23) to (start + 0, 65)
+- Code(Counter(8)) at (prev + 0, 65) to (start + 0, 66)
+- Code(Expression(23, Sub)) at (prev + 0, 67) to (start + 0, 96)
+    = (c18 - c8)
+- Code(Counter(9)) at (prev + 0, 96) to (start + 0, 97)
+- Code(Expression(22, Sub)) at (prev + 1, 13) to (start + 0, 32)
+    = ((c18 - c8) - c9)
+- Code(Expression(33, Sub)) at (prev + 4, 17) to (start + 0, 20)
+    = (((((c0 + (c1 + c2)) - c3) - c16) - c10) - c11)
+- Code(Expression(35, Sub)) at (prev + 0, 23) to (start + 0, 66)
+    = (((c0 + (c1 + c2)) - c3) - c16)
+- Code(Counter(10)) at (prev + 0, 66) to (start + 0, 67)
+- Code(Expression(34, Sub)) at (prev + 0, 68) to (start + 0, 97)
+    = ((((c0 + (c1 + c2)) - c3) - c16) - c10)
+- Code(Counter(11)) at (prev + 0, 97) to (start + 0, 98)
+- Code(Expression(33, Sub)) at (prev + 1, 13) to (start + 0, 32)
+    = (((((c0 + (c1 + c2)) - c3) - c16) - c10) - c11)
+- Code(Expression(40, Sub)) at (prev + 1, 17) to (start + 0, 20)
+    = ((c17 - c12) - c13)
 - Code(Counter(17)) at (prev + 0, 23) to (start + 1, 54)
-- Code(Zero) at (prev + 1, 54) to (start + 0, 55)
-- Code(Expression(25, Sub)) at (prev + 1, 18) to (start + 0, 47)
-    = (c17 - Zero)
-- Code(Zero) at (prev + 0, 47) to (start + 0, 48)
-- Code(Expression(24, Sub)) at (prev + 1, 13) to (start + 0, 32)
-    = ((c17 - Zero) - Zero)
-- Code(Expression(29, Sub)) at (prev + 1, 17) to (start + 0, 20)
-    = ((c19 - Zero) - Zero)
+- Code(Counter(12)) at (prev + 1, 54) to (start + 0, 55)
+- Code(Expression(41, Sub)) at (prev + 1, 18) to (start + 0, 47)
+    = (c17 - c12)
+- Code(Counter(13)) at (prev + 0, 47) to (start + 0, 48)
+- Code(Expression(40, Sub)) at (prev + 1, 13) to (start + 0, 32)
+    = ((c17 - c12) - c13)
+- Code(Expression(45, Sub)) at (prev + 1, 17) to (start + 0, 20)
+    = ((c19 - c14) - c15)
 - Code(Counter(19)) at (prev + 0, 23) to (start + 1, 54)
-- Code(Zero) at (prev + 2, 17) to (start + 0, 18)
-- Code(Expression(30, Sub)) at (prev + 1, 18) to (start + 0, 47)
-    = (c19 - Zero)
-- Code(Zero) at (prev + 1, 17) to (start + 0, 18)
-- Code(Expression(29, Sub)) at (prev + 2, 13) to (start + 0, 32)
-    = ((c19 - Zero) - Zero)
+- Code(Counter(14)) at (prev + 2, 17) to (start + 0, 18)
+- Code(Expression(46, Sub)) at (prev + 1, 18) to (start + 0, 47)
+    = (c19 - c14)
+- Code(Counter(15)) at (prev + 1, 17) to (start + 0, 18)
+- Code(Expression(45, Sub)) at (prev + 2, 13) to (start + 0, 32)
+    = ((c19 - c14) - c15)
 - Code(Counter(3)) at (prev + 3, 5) to (start + 0, 11)
-- Code(Expression(31, Add)) at (prev + 1, 1) to (start + 0, 2)
-    = (((Zero + ((c6 + Zero) + Zero)) + Zero) + c3)
+- Code(Expression(47, Add)) at (prev + 1, 1) to (start + 0, 2)
+    = ((((c4 + c5) + ((c6 + c7) + (c8 + c9))) + ((c10 + c11) + ((c12 + c13) + (c14 + c15)))) + c3)