coverage: Simplify counter expressions using simple algebra

Some of these cases currently don't occur in practice, but are included for
completeness, and to avoid having to add them later as branch coverage and
MC/DC coverage start building more complex expressions.

6 files changed, 114 insertions, 199 deletions

diff --git a/tests/coverage/branch/generics.cov-map b/tests/coverage/branch/generics.cov-map
index d729b0c260a..2e5668c8b56 100644
--- a/tests/coverage/branch/generics.cov-map
+++ b/tests/coverage/branch/generics.cov-map
@@ -1,10 +1,9 @@
 Function name: generics::print_size::<()>
-Raw bytes (35): 0x[01, 01, 02, 01, 05, 05, 02, 05, 01, 06, 01, 01, 24, 20, 05, 02, 01, 08, 00, 24, 05, 00, 25, 02, 06, 02, 02, 0c, 02, 06, 07, 03, 01, 00, 02]
+Raw bytes (33): 0x[01, 01, 01, 01, 05, 05, 01, 06, 01, 01, 24, 20, 05, 02, 01, 08, 00, 24, 05, 00, 25, 02, 06, 02, 02, 0c, 02, 06, 01, 03, 01, 00, 02]
 Number of files: 1
 - file 0 => global file 1
-Number of expressions: 2
+Number of expressions: 1
 - expression 0 operands: lhs = Counter(0), rhs = Counter(1)
-- expression 1 operands: lhs = Counter(1), rhs = Expression(0, Sub)
 Number of file 0 mappings: 5
 - Code(Counter(0)) at (prev + 6, 1) to (start + 1, 36)
 - Branch { true: Counter(1), false: Expression(0, Sub) } at (prev + 1, 8) to (start + 0, 36)
@@ -13,16 +12,14 @@ Number of file 0 mappings: 5
 - Code(Counter(1)) at (prev + 0, 37) to (start + 2, 6)
 - Code(Expression(0, Sub)) at (prev + 2, 12) to (start + 2, 6)
     = (c0 - c1)
-- Code(Expression(1, Add)) at (prev + 3, 1) to (start + 0, 2)
-    = (c1 + (c0 - c1))
+- Code(Counter(0)) at (prev + 3, 1) to (start + 0, 2)
 
 Function name: generics::print_size::<u32>
-Raw bytes (35): 0x[01, 01, 02, 01, 05, 05, 02, 05, 01, 06, 01, 01, 24, 20, 05, 02, 01, 08, 00, 24, 05, 00, 25, 02, 06, 02, 02, 0c, 02, 06, 07, 03, 01, 00, 02]
+Raw bytes (33): 0x[01, 01, 01, 01, 05, 05, 01, 06, 01, 01, 24, 20, 05, 02, 01, 08, 00, 24, 05, 00, 25, 02, 06, 02, 02, 0c, 02, 06, 01, 03, 01, 00, 02]
 Number of files: 1
 - file 0 => global file 1
-Number of expressions: 2
+Number of expressions: 1
 - expression 0 operands: lhs = Counter(0), rhs = Counter(1)
-- expression 1 operands: lhs = Counter(1), rhs = Expression(0, Sub)
 Number of file 0 mappings: 5
 - Code(Counter(0)) at (prev + 6, 1) to (start + 1, 36)
 - Branch { true: Counter(1), false: Expression(0, Sub) } at (prev + 1, 8) to (start + 0, 36)
@@ -31,16 +28,14 @@ Number of file 0 mappings: 5
 - Code(Counter(1)) at (prev + 0, 37) to (start + 2, 6)
 - Code(Expression(0, Sub)) at (prev + 2, 12) to (start + 2, 6)
     = (c0 - c1)
-- Code(Expression(1, Add)) at (prev + 3, 1) to (start + 0, 2)
-    = (c1 + (c0 - c1))
+- Code(Counter(0)) at (prev + 3, 1) to (start + 0, 2)
 
 Function name: generics::print_size::<u64>
-Raw bytes (35): 0x[01, 01, 02, 01, 05, 05, 02, 05, 01, 06, 01, 01, 24, 20, 05, 02, 01, 08, 00, 24, 05, 00, 25, 02, 06, 02, 02, 0c, 02, 06, 07, 03, 01, 00, 02]
+Raw bytes (33): 0x[01, 01, 01, 01, 05, 05, 01, 06, 01, 01, 24, 20, 05, 02, 01, 08, 00, 24, 05, 00, 25, 02, 06, 02, 02, 0c, 02, 06, 01, 03, 01, 00, 02]
 Number of files: 1
 - file 0 => global file 1
-Number of expressions: 2
+Number of expressions: 1
 - expression 0 operands: lhs = Counter(0), rhs = Counter(1)
-- expression 1 operands: lhs = Counter(1), rhs = Expression(0, Sub)
 Number of file 0 mappings: 5
 - Code(Counter(0)) at (prev + 6, 1) to (start + 1, 36)
 - Branch { true: Counter(1), false: Expression(0, Sub) } at (prev + 1, 8) to (start + 0, 36)
@@ -49,6 +44,5 @@ Number of file 0 mappings: 5
 - Code(Counter(1)) at (prev + 0, 37) to (start + 2, 6)
 - Code(Expression(0, Sub)) at (prev + 2, 12) to (start + 2, 6)
     = (c0 - c1)
-- Code(Expression(1, Add)) at (prev + 3, 1) to (start + 0, 2)
-    = (c1 + (c0 - c1))
+- Code(Counter(0)) at (prev + 3, 1) to (start + 0, 2)
 
diff --git a/tests/coverage/branch/if-let.cov-map b/tests/coverage/branch/if-let.cov-map
index 0c7d986933e..0b098bc6497 100644
--- a/tests/coverage/branch/if-let.cov-map
+++ b/tests/coverage/branch/if-let.cov-map
@@ -1,10 +1,9 @@
 Function name: if_let::if_let
-Raw bytes (45): 0x[01, 01, 02, 05, 09, 09, 02, 07, 01, 0c, 01, 01, 10, 20, 02, 09, 03, 0c, 00, 13, 02, 00, 11, 00, 12, 05, 00, 16, 00, 1b, 02, 00, 1c, 02, 06, 09, 02, 0c, 02, 06, 07, 03, 05, 01, 02]
+Raw bytes (43): 0x[01, 01, 01, 05, 09, 07, 01, 0c, 01, 01, 10, 20, 02, 09, 03, 0c, 00, 13, 02, 00, 11, 00, 12, 05, 00, 16, 00, 1b, 02, 00, 1c, 02, 06, 09, 02, 0c, 02, 06, 05, 03, 05, 01, 02]
 Number of files: 1
 - file 0 => global file 1
-Number of expressions: 2
+Number of expressions: 1
 - expression 0 operands: lhs = Counter(1), rhs = Counter(2)
-- expression 1 operands: lhs = Counter(2), rhs = Expression(0, Sub)
 Number of file 0 mappings: 7
 - Code(Counter(0)) at (prev + 12, 1) to (start + 1, 16)
 - Branch { true: Expression(0, Sub), false: Counter(2) } at (prev + 3, 12) to (start + 0, 19)
@@ -16,8 +15,7 @@ Number of file 0 mappings: 7
 - Code(Expression(0, Sub)) at (prev + 0, 28) to (start + 2, 6)
     = (c1 - c2)
 - Code(Counter(2)) at (prev + 2, 12) to (start + 2, 6)
-- Code(Expression(1, Add)) at (prev + 3, 5) to (start + 1, 2)
-    = (c2 + (c1 - c2))
+- Code(Counter(1)) at (prev + 3, 5) to (start + 1, 2)
 
 Function name: if_let::if_let_chain
 Raw bytes (66): 0x[01, 01, 04, 01, 05, 05, 09, 0f, 0d, 05, 09, 0a, 01, 17, 01, 00, 33, 20, 02, 05, 01, 0c, 00, 13, 02, 00, 11, 00, 12, 01, 00, 16, 00, 17, 20, 0d, 09, 01, 10, 00, 17, 0d, 00, 15, 00, 16, 02, 00, 1a, 00, 1b, 0d, 01, 05, 03, 06, 0f, 03, 0c, 02, 06, 0b, 03, 05, 01, 02]
diff --git a/tests/coverage/branch/if.cov-map b/tests/coverage/branch/if.cov-map
index 50f6216e069..7f4ee980e26 100644
--- a/tests/coverage/branch/if.cov-map
+++ b/tests/coverage/branch/if.cov-map
@@ -24,51 +24,17 @@ Number of file 0 mappings: 8
     = (c4 + (c3 + (c1 - c2)))
 
 Function name: if::branch_not
-Raw bytes (224): 0x[01, 01, 29, 05, 09, 09, 02, a3, 01, 0d, 09, 02, a3, 01, 0d, 09, 02, 0d, 9e, 01, a3, 01, 0d, 09, 02, 9b, 01, 11, 0d, 9e, 01, a3, 01, 0d, 09, 02, 9b, 01, 11, 0d, 9e, 01, a3, 01, 0d, 09, 02, 11, 96, 01, 9b, 01, 11, 0d, 9e, 01, a3, 01, 0d, 09, 02, 93, 01, 15, 11, 96, 01, 9b, 01, 11, 0d, 9e, 01, a3, 01, 0d, 09, 02, 93, 01, 15, 11, 96, 01, 9b, 01, 11, 0d, 9e, 01, a3, 01, 0d, 09, 02, 15, 8e, 01, 93, 01, 15, 11, 96, 01, 9b, 01, 11, 0d, 9e, 01, a3, 01, 0d, 09, 02, 12, 01, 0c, 01, 01, 10, 05, 03, 08, 00, 09, 20, 09, 02, 00, 08, 00, 09, 09, 01, 09, 00, 11, 02, 01, 06, 00, 07, a3, 01, 01, 08, 00, 0a, 20, 9e, 01, 0d, 00, 08, 00, 0a, 9e, 01, 00, 0b, 02, 06, 0d, 02, 06, 00, 07, 9b, 01, 01, 08, 00, 0b, 20, 11, 96, 01, 00, 08, 00, 0b, 11, 00, 0c, 02, 06, 96, 01, 02, 06, 00, 07, 93, 01, 01, 08, 00, 0c, 20, 8e, 01, 15, 00, 08, 00, 0c, 8e, 01, 00, 0d, 02, 06, 15, 02, 06, 00, 07, 8b, 01, 01, 01, 00, 02]
+Raw bytes (116): 0x[01, 01, 07, 05, 09, 05, 0d, 05, 0d, 05, 11, 05, 11, 05, 15, 05, 15, 12, 01, 0c, 01, 01, 10, 05, 03, 08, 00, 09, 20, 09, 02, 00, 08, 00, 09, 09, 01, 09, 00, 11, 02, 01, 06, 00, 07, 05, 01, 08, 00, 0a, 20, 0a, 0d, 00, 08, 00, 0a, 0a, 00, 0b, 02, 06, 0d, 02, 06, 00, 07, 05, 01, 08, 00, 0b, 20, 11, 12, 00, 08, 00, 0b, 11, 00, 0c, 02, 06, 12, 02, 06, 00, 07, 05, 01, 08, 00, 0c, 20, 1a, 15, 00, 08, 00, 0c, 1a, 00, 0d, 02, 06, 15, 02, 06, 00, 07, 05, 01, 01, 00, 02]
 Number of files: 1
 - file 0 => global file 1
-Number of expressions: 41
+Number of expressions: 7
 - expression 0 operands: lhs = Counter(1), rhs = Counter(2)
-- expression 1 operands: lhs = Counter(2), rhs = Expression(0, Sub)
-- expression 2 operands: lhs = Expression(40, Add), rhs = Counter(3)
-- expression 3 operands: lhs = Counter(2), rhs = Expression(0, Sub)
-- expression 4 operands: lhs = Expression(40, Add), rhs = Counter(3)
-- expression 5 operands: lhs = Counter(2), rhs = Expression(0, Sub)
-- expression 6 operands: lhs = Counter(3), rhs = Expression(39, Sub)
-- expression 7 operands: lhs = Expression(40, Add), rhs = Counter(3)
-- expression 8 operands: lhs = Counter(2), rhs = Expression(0, Sub)
-- expression 9 operands: lhs = Expression(38, Add), rhs = Counter(4)
-- expression 10 operands: lhs = Counter(3), rhs = Expression(39, Sub)
-- expression 11 operands: lhs = Expression(40, Add), rhs = Counter(3)
-- expression 12 operands: lhs = Counter(2), rhs = Expression(0, Sub)
-- expression 13 operands: lhs = Expression(38, Add), rhs = Counter(4)
-- expression 14 operands: lhs = Counter(3), rhs = Expression(39, Sub)
-- expression 15 operands: lhs = Expression(40, Add), rhs = Counter(3)
-- expression 16 operands: lhs = Counter(2), rhs = Expression(0, Sub)
-- expression 17 operands: lhs = Counter(4), rhs = Expression(37, Sub)
-- expression 18 operands: lhs = Expression(38, Add), rhs = Counter(4)
-- expression 19 operands: lhs = Counter(3), rhs = Expression(39, Sub)
-- expression 20 operands: lhs = Expression(40, Add), rhs = Counter(3)
-- expression 21 operands: lhs = Counter(2), rhs = Expression(0, Sub)
-- expression 22 operands: lhs = Expression(36, Add), rhs = Counter(5)
-- expression 23 operands: lhs = Counter(4), rhs = Expression(37, Sub)
-- expression 24 operands: lhs = Expression(38, Add), rhs = Counter(4)
-- expression 25 operands: lhs = Counter(3), rhs = Expression(39, Sub)
-- expression 26 operands: lhs = Expression(40, Add), rhs = Counter(3)
-- expression 27 operands: lhs = Counter(2), rhs = Expression(0, Sub)
-- expression 28 operands: lhs = Expression(36, Add), rhs = Counter(5)
-- expression 29 operands: lhs = Counter(4), rhs = Expression(37, Sub)
-- expression 30 operands: lhs = Expression(38, Add), rhs = Counter(4)
-- expression 31 operands: lhs = Counter(3), rhs = Expression(39, Sub)
-- expression 32 operands: lhs = Expression(40, Add), rhs = Counter(3)
-- expression 33 operands: lhs = Counter(2), rhs = Expression(0, Sub)
-- expression 34 operands: lhs = Counter(5), rhs = Expression(35, Sub)
-- expression 35 operands: lhs = Expression(36, Add), rhs = Counter(5)
-- expression 36 operands: lhs = Counter(4), rhs = Expression(37, Sub)
-- expression 37 operands: lhs = Expression(38, Add), rhs = Counter(4)
-- expression 38 operands: lhs = Counter(3), rhs = Expression(39, Sub)
-- expression 39 operands: lhs = Expression(40, Add), rhs = Counter(3)
-- expression 40 operands: lhs = Counter(2), rhs = Expression(0, Sub)
+- expression 1 operands: lhs = Counter(1), rhs = Counter(3)
+- expression 2 operands: lhs = Counter(1), rhs = Counter(3)
+- expression 3 operands: lhs = Counter(1), rhs = Counter(4)
+- expression 4 operands: lhs = Counter(1), rhs = Counter(4)
+- expression 5 operands: lhs = Counter(1), rhs = Counter(5)
+- expression 6 operands: lhs = Counter(1), rhs = Counter(5)
 Number of file 0 mappings: 18
 - Code(Counter(0)) at (prev + 12, 1) to (start + 1, 16)
 - Code(Counter(1)) at (prev + 3, 8) to (start + 0, 9)
@@ -78,60 +44,39 @@ Number of file 0 mappings: 18
 - Code(Counter(2)) at (prev + 1, 9) to (start + 0, 17)
 - Code(Expression(0, Sub)) at (prev + 1, 6) to (start + 0, 7)
     = (c1 - c2)
-- Code(Expression(40, Add)) at (prev + 1, 8) to (start + 0, 10)
-    = (c2 + (c1 - c2))
-- Branch { true: Expression(39, Sub), false: Counter(3) } at (prev + 0, 8) to (start + 0, 10)
-    true  = ((c2 + (c1 - c2)) - c3)
+- Code(Counter(1)) at (prev + 1, 8) to (start + 0, 10)
+- Branch { true: Expression(2, Sub), false: Counter(3) } at (prev + 0, 8) to (start + 0, 10)
+    true  = (c1 - c3)
     false = c3
-- Code(Expression(39, Sub)) at (prev + 0, 11) to (start + 2, 6)
-    = ((c2 + (c1 - c2)) - c3)
+- Code(Expression(2, Sub)) at (prev + 0, 11) to (start + 2, 6)
+    = (c1 - c3)
 - Code(Counter(3)) at (prev + 2, 6) to (start + 0, 7)
-- Code(Expression(38, Add)) at (prev + 1, 8) to (start + 0, 11)
-    = (c3 + ((c2 + (c1 - c2)) - c3))
-- Branch { true: Counter(4), false: Expression(37, Sub) } at (prev + 0, 8) to (start + 0, 11)
+- Code(Counter(1)) at (prev + 1, 8) to (start + 0, 11)
+- Branch { true: Counter(4), false: Expression(4, Sub) } at (prev + 0, 8) to (start + 0, 11)
     true  = c4
-    false = ((c3 + ((c2 + (c1 - c2)) - c3)) - c4)
+    false = (c1 - c4)
 - Code(Counter(4)) at (prev + 0, 12) to (start + 2, 6)
-- Code(Expression(37, Sub)) at (prev + 2, 6) to (start + 0, 7)
-    = ((c3 + ((c2 + (c1 - c2)) - c3)) - c4)
-- Code(Expression(36, Add)) at (prev + 1, 8) to (start + 0, 12)
-    = (c4 + ((c3 + ((c2 + (c1 - c2)) - c3)) - c4))
-- Branch { true: Expression(35, Sub), false: Counter(5) } at (prev + 0, 8) to (start + 0, 12)
-    true  = ((c4 + ((c3 + ((c2 + (c1 - c2)) - c3)) - c4)) - c5)
+- Code(Expression(4, Sub)) at (prev + 2, 6) to (start + 0, 7)
+    = (c1 - c4)
+- Code(Counter(1)) at (prev + 1, 8) to (start + 0, 12)
+- Branch { true: Expression(6, Sub), false: Counter(5) } at (prev + 0, 8) to (start + 0, 12)
+    true  = (c1 - c5)
     false = c5
-- Code(Expression(35, Sub)) at (prev + 0, 13) to (start + 2, 6)
-    = ((c4 + ((c3 + ((c2 + (c1 - c2)) - c3)) - c4)) - c5)
+- Code(Expression(6, Sub)) at (prev + 0, 13) to (start + 2, 6)
+    = (c1 - c5)
 - Code(Counter(5)) at (prev + 2, 6) to (start + 0, 7)
-- Code(Expression(34, Add)) at (prev + 1, 1) to (start + 0, 2)
-    = (c5 + ((c4 + ((c3 + ((c2 + (c1 - c2)) - c3)) - c4)) - c5))
+- Code(Counter(1)) at (prev + 1, 1) to (start + 0, 2)
 
 Function name: if::branch_not_as
-Raw bytes (124): 0x[01, 01, 16, 05, 09, 09, 02, 57, 0d, 09, 02, 57, 0d, 09, 02, 0d, 52, 57, 0d, 09, 02, 4f, 11, 0d, 52, 57, 0d, 09, 02, 4f, 11, 0d, 52, 57, 0d, 09, 02, 11, 4a, 4f, 11, 0d, 52, 57, 0d, 09, 02, 0e, 01, 1d, 01, 01, 10, 05, 03, 08, 00, 14, 20, 02, 09, 00, 08, 00, 14, 02, 00, 15, 02, 06, 09, 02, 06, 00, 07, 57, 01, 08, 00, 15, 20, 0d, 52, 00, 08, 00, 15, 0d, 00, 16, 02, 06, 52, 02, 06, 00, 07, 4f, 01, 08, 00, 16, 20, 4a, 11, 00, 08, 00, 16, 4a, 00, 17, 02, 06, 11, 02, 06, 00, 07, 47, 01, 01, 00, 02]
+Raw bytes (90): 0x[01, 01, 05, 05, 09, 05, 0d, 05, 0d, 05, 11, 05, 11, 0e, 01, 1d, 01, 01, 10, 05, 03, 08, 00, 14, 20, 02, 09, 00, 08, 00, 14, 02, 00, 15, 02, 06, 09, 02, 06, 00, 07, 05, 01, 08, 00, 15, 20, 0d, 0a, 00, 08, 00, 15, 0d, 00, 16, 02, 06, 0a, 02, 06, 00, 07, 05, 01, 08, 00, 16, 20, 12, 11, 00, 08, 00, 16, 12, 00, 17, 02, 06, 11, 02, 06, 00, 07, 05, 01, 01, 00, 02]
 Number of files: 1
 - file 0 => global file 1
-Number of expressions: 22
+Number of expressions: 5
 - expression 0 operands: lhs = Counter(1), rhs = Counter(2)
-- expression 1 operands: lhs = Counter(2), rhs = Expression(0, Sub)
-- expression 2 operands: lhs = Expression(21, Add), rhs = Counter(3)
-- expression 3 operands: lhs = Counter(2), rhs = Expression(0, Sub)
-- expression 4 operands: lhs = Expression(21, Add), rhs = Counter(3)
-- expression 5 operands: lhs = Counter(2), rhs = Expression(0, Sub)
-- expression 6 operands: lhs = Counter(3), rhs = Expression(20, Sub)
-- expression 7 operands: lhs = Expression(21, Add), rhs = Counter(3)
-- expression 8 operands: lhs = Counter(2), rhs = Expression(0, Sub)
-- expression 9 operands: lhs = Expression(19, Add), rhs = Counter(4)
-- expression 10 operands: lhs = Counter(3), rhs = Expression(20, Sub)
-- expression 11 operands: lhs = Expression(21, Add), rhs = Counter(3)
-- expression 12 operands: lhs = Counter(2), rhs = Expression(0, Sub)
-- expression 13 operands: lhs = Expression(19, Add), rhs = Counter(4)
-- expression 14 operands: lhs = Counter(3), rhs = Expression(20, Sub)
-- expression 15 operands: lhs = Expression(21, Add), rhs = Counter(3)
-- expression 16 operands: lhs = Counter(2), rhs = Expression(0, Sub)
-- expression 17 operands: lhs = Counter(4), rhs = Expression(18, Sub)
-- expression 18 operands: lhs = Expression(19, Add), rhs = Counter(4)
-- expression 19 operands: lhs = Counter(3), rhs = Expression(20, Sub)
-- expression 20 operands: lhs = Expression(21, Add), rhs = Counter(3)
-- expression 21 operands: lhs = Counter(2), rhs = Expression(0, Sub)
+- expression 1 operands: lhs = Counter(1), rhs = Counter(3)
+- expression 2 operands: lhs = Counter(1), rhs = Counter(3)
+- expression 3 operands: lhs = Counter(1), rhs = Counter(4)
+- expression 4 operands: lhs = Counter(1), rhs = Counter(4)
 Number of file 0 mappings: 14
 - Code(Counter(0)) at (prev + 29, 1) to (start + 1, 16)
 - Code(Counter(1)) at (prev + 3, 8) to (start + 0, 20)
@@ -141,24 +86,21 @@ Number of file 0 mappings: 14
 - Code(Expression(0, Sub)) at (prev + 0, 21) to (start + 2, 6)
     = (c1 - c2)
 - Code(Counter(2)) at (prev + 2, 6) to (start + 0, 7)
-- Code(Expression(21, Add)) at (prev + 1, 8) to (start + 0, 21)
-    = (c2 + (c1 - c2))
-- Branch { true: Counter(3), false: Expression(20, Sub) } at (prev + 0, 8) to (start + 0, 21)
+- Code(Counter(1)) at (prev + 1, 8) to (start + 0, 21)
+- Branch { true: Counter(3), false: Expression(2, Sub) } at (prev + 0, 8) to (start + 0, 21)
     true  = c3
-    false = ((c2 + (c1 - c2)) - c3)
+    false = (c1 - c3)
 - Code(Counter(3)) at (prev + 0, 22) to (start + 2, 6)
-- Code(Expression(20, Sub)) at (prev + 2, 6) to (start + 0, 7)
-    = ((c2 + (c1 - c2)) - c3)
-- Code(Expression(19, Add)) at (prev + 1, 8) to (start + 0, 22)
-    = (c3 + ((c2 + (c1 - c2)) - c3))
-- Branch { true: Expression(18, Sub), false: Counter(4) } at (prev + 0, 8) to (start + 0, 22)
-    true  = ((c3 + ((c2 + (c1 - c2)) - c3)) - c4)
+- Code(Expression(2, Sub)) at (prev + 2, 6) to (start + 0, 7)
+    = (c1 - c3)
+- Code(Counter(1)) at (prev + 1, 8) to (start + 0, 22)
+- Branch { true: Expression(4, Sub), false: Counter(4) } at (prev + 0, 8) to (start + 0, 22)
+    true  = (c1 - c4)
     false = c4
-- Code(Expression(18, Sub)) at (prev + 0, 23) to (start + 2, 6)
-    = ((c3 + ((c2 + (c1 - c2)) - c3)) - c4)
+- Code(Expression(4, Sub)) at (prev + 0, 23) to (start + 2, 6)
+    = (c1 - c4)
 - Code(Counter(4)) at (prev + 2, 6) to (start + 0, 7)
-- Code(Expression(17, Add)) at (prev + 1, 1) to (start + 0, 2)
-    = (c4 + ((c3 + ((c2 + (c1 - c2)) - c3)) - c4))
+- Code(Counter(1)) at (prev + 1, 1) to (start + 0, 2)
 
 Function name: if::branch_or
 Raw bytes (56): 0x[01, 01, 04, 05, 09, 09, 0d, 0f, 11, 09, 0d, 08, 01, 35, 01, 01, 10, 05, 03, 08, 00, 09, 20, 09, 02, 00, 08, 00, 09, 02, 00, 0d, 00, 0e, 20, 0d, 11, 00, 0d, 00, 0e, 0f, 00, 0f, 02, 06, 11, 02, 0c, 02, 06, 0b, 03, 01, 00, 02]
diff --git a/tests/coverage/branch/lazy-boolean.cov-map b/tests/coverage/branch/lazy-boolean.cov-map
index e2d731022d7..09ce9137673 100644
--- a/tests/coverage/branch/lazy-boolean.cov-map
+++ b/tests/coverage/branch/lazy-boolean.cov-map
@@ -1,44 +1,35 @@
 Function name: lazy_boolean::branch_and
-Raw bytes (42): 0x[01, 01, 03, 09, 0a, 05, 09, 05, 09, 06, 01, 13, 01, 01, 10, 03, 04, 09, 00, 0a, 05, 00, 0d, 00, 0e, 20, 09, 0a, 00, 0d, 00, 0e, 09, 00, 12, 00, 13, 03, 01, 05, 01, 02]
+Raw bytes (38): 0x[01, 01, 01, 05, 09, 06, 01, 13, 01, 01, 10, 05, 04, 09, 00, 0a, 05, 00, 0d, 00, 0e, 20, 09, 02, 00, 0d, 00, 0e, 09, 00, 12, 00, 13, 05, 01, 05, 01, 02]
 Number of files: 1
 - file 0 => global file 1
-Number of expressions: 3
-- expression 0 operands: lhs = Counter(2), rhs = Expression(2, Sub)
-- expression 1 operands: lhs = Counter(1), rhs = Counter(2)
-- expression 2 operands: lhs = Counter(1), rhs = Counter(2)
+Number of expressions: 1
+- expression 0 operands: lhs = Counter(1), rhs = Counter(2)
 Number of file 0 mappings: 6
 - Code(Counter(0)) at (prev + 19, 1) to (start + 1, 16)
-- Code(Expression(0, Add)) at (prev + 4, 9) to (start + 0, 10)
-    = (c2 + (c1 - c2))
+- Code(Counter(1)) at (prev + 4, 9) to (start + 0, 10)
 - Code(Counter(1)) at (prev + 0, 13) to (start + 0, 14)
-- Branch { true: Counter(2), false: Expression(2, Sub) } at (prev + 0, 13) to (start + 0, 14)
+- Branch { true: Counter(2), false: Expression(0, Sub) } at (prev + 0, 13) to (start + 0, 14)
     true  = c2
     false = (c1 - c2)
 - Code(Counter(2)) at (prev + 0, 18) to (start + 0, 19)
-- Code(Expression(0, Add)) at (prev + 1, 5) to (start + 1, 2)
-    = (c2 + (c1 - c2))
+- Code(Counter(1)) at (prev + 1, 5) to (start + 1, 2)
 
 Function name: lazy_boolean::branch_or
-Raw bytes (44): 0x[01, 01, 04, 09, 0e, 05, 09, 05, 09, 05, 09, 06, 01, 1b, 01, 01, 10, 03, 04, 09, 00, 0a, 05, 00, 0d, 00, 0e, 20, 09, 0e, 00, 0d, 00, 0e, 0e, 00, 12, 00, 13, 03, 01, 05, 01, 02]
+Raw bytes (38): 0x[01, 01, 01, 05, 09, 06, 01, 1b, 01, 01, 10, 05, 04, 09, 00, 0a, 05, 00, 0d, 00, 0e, 20, 09, 02, 00, 0d, 00, 0e, 02, 00, 12, 00, 13, 05, 01, 05, 01, 02]
 Number of files: 1
 - file 0 => global file 1
-Number of expressions: 4
-- expression 0 operands: lhs = Counter(2), rhs = Expression(3, Sub)
-- expression 1 operands: lhs = Counter(1), rhs = Counter(2)
-- expression 2 operands: lhs = Counter(1), rhs = Counter(2)
-- expression 3 operands: lhs = Counter(1), rhs = Counter(2)
+Number of expressions: 1
+- expression 0 operands: lhs = Counter(1), rhs = Counter(2)
 Number of file 0 mappings: 6
 - Code(Counter(0)) at (prev + 27, 1) to (start + 1, 16)
-- Code(Expression(0, Add)) at (prev + 4, 9) to (start + 0, 10)
-    = (c2 + (c1 - c2))
+- Code(Counter(1)) at (prev + 4, 9) to (start + 0, 10)
 - Code(Counter(1)) at (prev + 0, 13) to (start + 0, 14)
-- Branch { true: Counter(2), false: Expression(3, Sub) } at (prev + 0, 13) to (start + 0, 14)
+- Branch { true: Counter(2), false: Expression(0, Sub) } at (prev + 0, 13) to (start + 0, 14)
     true  = c2
     false = (c1 - c2)
-- Code(Expression(3, Sub)) at (prev + 0, 18) to (start + 0, 19)
+- Code(Expression(0, Sub)) at (prev + 0, 18) to (start + 0, 19)
     = (c1 - c2)
-- Code(Expression(0, Add)) at (prev + 1, 5) to (start + 1, 2)
-    = (c2 + (c1 - c2))
+- Code(Counter(1)) at (prev + 1, 5) to (start + 1, 2)
 
 Function name: lazy_boolean::chain
 Raw bytes (149): 0x[01, 01, 13, 11, 07, 0b, 16, 15, 1a, 09, 0d, 05, 09, 05, 09, 09, 0d, 47, 25, 4b, 21, 19, 1d, 03, 19, 03, 19, 3e, 1d, 03, 19, 3e, 1d, 03, 19, 47, 25, 4b, 21, 19, 1d, 13, 01, 24, 01, 01, 10, 03, 04, 09, 00, 0a, 05, 00, 0d, 00, 12, 20, 09, 16, 00, 0d, 00, 12, 09, 00, 16, 00, 1b, 20, 0d, 1a, 00, 16, 00, 1b, 0d, 00, 1f, 00, 24, 20, 11, 15, 00, 1f, 00, 24, 11, 00, 28, 00, 2d, 03, 01, 05, 00, 11, 43, 03, 09, 00, 0a, 03, 00, 0d, 00, 12, 20, 19, 3e, 00, 0d, 00, 12, 3e, 00, 16, 00, 1b, 20, 1d, 3a, 00, 16, 00, 1b, 3a, 00, 1f, 00, 24, 20, 21, 25, 00, 1f, 00, 24, 25, 00, 28, 00, 2d, 43, 01, 05, 01, 02]
@@ -105,73 +96,71 @@ Number of file 0 mappings: 19
     = (((c6 + c7) + c8) + c9)
 
 Function name: lazy_boolean::nested_mixed
-Raw bytes (159): 0x[01, 01, 18, 07, 22, 11, 36, 3b, 11, 09, 0d, 26, 0d, 05, 09, 05, 09, 05, 09, 26, 0d, 05, 09, 09, 0d, 3b, 11, 09, 0d, 3b, 11, 09, 0d, 19, 5f, 1d, 21, 03, 15, 15, 19, 52, 56, 15, 19, 03, 15, 19, 5f, 1d, 21, 13, 01, 31, 01, 01, 10, 03, 04, 09, 00, 0a, 05, 00, 0e, 00, 13, 20, 09, 26, 00, 0e, 00, 13, 26, 00, 17, 00, 1d, 20, 0d, 22, 00, 17, 00, 1d, 3b, 00, 23, 00, 28, 20, 11, 36, 00, 23, 00, 28, 36, 00, 2c, 00, 33, 03, 01, 05, 00, 11, 5b, 03, 09, 00, 0a, 03, 00, 0e, 00, 13, 20, 15, 56, 00, 0e, 00, 13, 15, 00, 17, 00, 1c, 20, 19, 52, 00, 17, 00, 1c, 4f, 00, 22, 00, 28, 20, 1d, 21, 00, 22, 00, 28, 1d, 00, 2c, 00, 33, 5b, 01, 05, 01, 02]
+Raw bytes (155): 0x[01, 01, 16, 33, 1a, 09, 0d, 1e, 0d, 05, 09, 05, 09, 05, 09, 1e, 0d, 05, 09, 09, 0d, 33, 11, 09, 0d, 33, 11, 09, 0d, 19, 57, 1d, 21, 03, 15, 15, 19, 4a, 4e, 15, 19, 03, 15, 19, 57, 1d, 21, 13, 01, 31, 01, 01, 10, 03, 04, 09, 00, 0a, 05, 00, 0e, 00, 13, 20, 09, 1e, 00, 0e, 00, 13, 1e, 00, 17, 00, 1d, 20, 0d, 1a, 00, 17, 00, 1d, 33, 00, 23, 00, 28, 20, 11, 2e, 00, 23, 00, 28, 2e, 00, 2c, 00, 33, 03, 01, 05, 00, 11, 53, 03, 09, 00, 0a, 03, 00, 0e, 00, 13, 20, 15, 4e, 00, 0e, 00, 13, 15, 00, 17, 00, 1c, 20, 19, 4a, 00, 17, 00, 1c, 47, 00, 22, 00, 28, 20, 1d, 21, 00, 22, 00, 28, 1d, 00, 2c, 00, 33, 53, 01, 05, 01, 02]
 Number of files: 1
 - file 0 => global file 1
-Number of expressions: 24
-- expression 0 operands: lhs = Expression(1, Add), rhs = Expression(8, Sub)
-- expression 1 operands: lhs = Counter(4), rhs = Expression(13, Sub)
-- expression 2 operands: lhs = Expression(14, Add), rhs = Counter(4)
-- expression 3 operands: lhs = Counter(2), rhs = Counter(3)
-- expression 4 operands: lhs = Expression(9, Sub), rhs = Counter(3)
+Number of expressions: 22
+- expression 0 operands: lhs = Expression(12, Add), rhs = Expression(6, Sub)
+- expression 1 operands: lhs = Counter(2), rhs = Counter(3)
+- expression 2 operands: lhs = Expression(7, Sub), rhs = Counter(3)
+- expression 3 operands: lhs = Counter(1), rhs = Counter(2)
+- expression 4 operands: lhs = Counter(1), rhs = Counter(2)
 - expression 5 operands: lhs = Counter(1), rhs = Counter(2)
-- expression 6 operands: lhs = Counter(1), rhs = Counter(2)
+- expression 6 operands: lhs = Expression(7, Sub), rhs = Counter(3)
 - expression 7 operands: lhs = Counter(1), rhs = Counter(2)
-- expression 8 operands: lhs = Expression(9, Sub), rhs = Counter(3)
-- expression 9 operands: lhs = Counter(1), rhs = Counter(2)
+- expression 8 operands: lhs = Counter(2), rhs = Counter(3)
+- expression 9 operands: lhs = Expression(12, Add), rhs = Counter(4)
 - expression 10 operands: lhs = Counter(2), rhs = Counter(3)
-- expression 11 operands: lhs = Expression(14, Add), rhs = Counter(4)
+- expression 11 operands: lhs = Expression(12, Add), rhs = Counter(4)
 - expression 12 operands: lhs = Counter(2), rhs = Counter(3)
-- expression 13 operands: lhs = Expression(14, Add), rhs = Counter(4)
-- expression 14 operands: lhs = Counter(2), rhs = Counter(3)
-- expression 15 operands: lhs = Counter(6), rhs = Expression(23, Add)
-- expression 16 operands: lhs = Counter(7), rhs = Counter(8)
-- expression 17 operands: lhs = Expression(0, Add), rhs = Counter(5)
+- expression 13 operands: lhs = Counter(6), rhs = Expression(21, Add)
+- expression 14 operands: lhs = Counter(7), rhs = Counter(8)
+- expression 15 operands: lhs = Expression(0, Add), rhs = Counter(5)
+- expression 16 operands: lhs = Counter(5), rhs = Counter(6)
+- expression 17 operands: lhs = Expression(18, Sub), rhs = Expression(19, Sub)
 - expression 18 operands: lhs = Counter(5), rhs = Counter(6)
-- expression 19 operands: lhs = Expression(20, Sub), rhs = Expression(21, Sub)
-- expression 20 operands: lhs = Counter(5), rhs = Counter(6)
-- expression 21 operands: lhs = Expression(0, Add), rhs = Counter(5)
-- expression 22 operands: lhs = Counter(6), rhs = Expression(23, Add)
-- expression 23 operands: lhs = Counter(7), rhs = Counter(8)
+- expression 19 operands: lhs = Expression(0, Add), rhs = Counter(5)
+- expression 20 operands: lhs = Counter(6), rhs = Expression(21, Add)
+- expression 21 operands: lhs = Counter(7), rhs = Counter(8)
 Number of file 0 mappings: 19
 - Code(Counter(0)) at (prev + 49, 1) to (start + 1, 16)
 - Code(Expression(0, Add)) at (prev + 4, 9) to (start + 0, 10)
-    = ((c4 + ((c2 + c3) - c4)) + ((c1 - c2) - c3))
+    = ((c2 + c3) + ((c1 - c2) - c3))
 - Code(Counter(1)) at (prev + 0, 14) to (start + 0, 19)
-- Branch { true: Counter(2), false: Expression(9, Sub) } at (prev + 0, 14) to (start + 0, 19)
+- Branch { true: Counter(2), false: Expression(7, Sub) } at (prev + 0, 14) to (start + 0, 19)
     true  = c2
     false = (c1 - c2)
-- Code(Expression(9, Sub)) at (prev + 0, 23) to (start + 0, 29)
+- Code(Expression(7, Sub)) at (prev + 0, 23) to (start + 0, 29)
     = (c1 - c2)
-- Branch { true: Counter(3), false: Expression(8, Sub) } at (prev + 0, 23) to (start + 0, 29)
+- Branch { true: Counter(3), false: Expression(6, Sub) } at (prev + 0, 23) to (start + 0, 29)
     true  = c3
     false = ((c1 - c2) - c3)
-- Code(Expression(14, Add)) at (prev + 0, 35) to (start + 0, 40)
+- Code(Expression(12, Add)) at (prev + 0, 35) to (start + 0, 40)
     = (c2 + c3)
-- Branch { true: Counter(4), false: Expression(13, Sub) } at (prev + 0, 35) to (start + 0, 40)
+- Branch { true: Counter(4), false: Expression(11, Sub) } at (prev + 0, 35) to (start + 0, 40)
     true  = c4
     false = ((c2 + c3) - c4)
-- Code(Expression(13, Sub)) at (prev + 0, 44) to (start + 0, 51)
+- Code(Expression(11, Sub)) at (prev + 0, 44) to (start + 0, 51)
     = ((c2 + c3) - c4)
 - Code(Expression(0, Add)) at (prev + 1, 5) to (start + 0, 17)
-    = ((c4 + ((c2 + c3) - c4)) + ((c1 - c2) - c3))
-- Code(Expression(22, Add)) at (prev + 3, 9) to (start + 0, 10)
+    = ((c2 + c3) + ((c1 - c2) - c3))
+- Code(Expression(20, Add)) at (prev + 3, 9) to (start + 0, 10)
     = (c6 + (c7 + c8))
 - Code(Expression(0, Add)) at (prev + 0, 14) to (start + 0, 19)
-    = ((c4 + ((c2 + c3) - c4)) + ((c1 - c2) - c3))
-- Branch { true: Counter(5), false: Expression(21, Sub) } at (prev + 0, 14) to (start + 0, 19)
+    = ((c2 + c3) + ((c1 - c2) - c3))
+- Branch { true: Counter(5), false: Expression(19, Sub) } at (prev + 0, 14) to (start + 0, 19)
     true  = c5
-    false = (((c4 + ((c2 + c3) - c4)) + ((c1 - c2) - c3)) - c5)
+    false = (((c2 + c3) + ((c1 - c2) - c3)) - c5)
 - Code(Counter(5)) at (prev + 0, 23) to (start + 0, 28)
-- Branch { true: Counter(6), false: Expression(20, Sub) } at (prev + 0, 23) to (start + 0, 28)
+- Branch { true: Counter(6), false: Expression(18, Sub) } at (prev + 0, 23) to (start + 0, 28)
     true  = c6
     false = (c5 - c6)
-- Code(Expression(19, Add)) at (prev + 0, 34) to (start + 0, 40)
-    = ((c5 - c6) + (((c4 + ((c2 + c3) - c4)) + ((c1 - c2) - c3)) - c5))
+- Code(Expression(17, Add)) at (prev + 0, 34) to (start + 0, 40)
+    = ((c5 - c6) + (((c2 + c3) + ((c1 - c2) - c3)) - c5))
 - Branch { true: Counter(7), false: Counter(8) } at (prev + 0, 34) to (start + 0, 40)
     true  = c7
     false = c8
 - Code(Counter(7)) at (prev + 0, 44) to (start + 0, 51)
-- Code(Expression(22, Add)) at (prev + 1, 5) to (start + 1, 2)
+- Code(Expression(20, Add)) at (prev + 1, 5) to (start + 1, 2)
     = (c6 + (c7 + c8))
 
diff --git a/tests/coverage/branch/let-else.cov-map b/tests/coverage/branch/let-else.cov-map
index c7f7adddbc2..07079934464 100644
--- a/tests/coverage/branch/let-else.cov-map
+++ b/tests/coverage/branch/let-else.cov-map
@@ -1,10 +1,9 @@
 Function name: let_else::let_else
-Raw bytes (45): 0x[01, 01, 02, 05, 09, 09, 02, 07, 01, 0c, 01, 01, 10, 20, 02, 09, 03, 09, 00, 10, 02, 00, 0e, 00, 0f, 05, 00, 13, 00, 18, 09, 01, 09, 01, 0f, 02, 04, 05, 00, 0b, 07, 01, 01, 00, 02]
+Raw bytes (43): 0x[01, 01, 01, 05, 09, 07, 01, 0c, 01, 01, 10, 20, 02, 09, 03, 09, 00, 10, 02, 00, 0e, 00, 0f, 05, 00, 13, 00, 18, 09, 01, 09, 01, 0f, 02, 04, 05, 00, 0b, 05, 01, 01, 00, 02]
 Number of files: 1
 - file 0 => global file 1
-Number of expressions: 2
+Number of expressions: 1
 - expression 0 operands: lhs = Counter(1), rhs = Counter(2)
-- expression 1 operands: lhs = Counter(2), rhs = Expression(0, Sub)
 Number of file 0 mappings: 7
 - Code(Counter(0)) at (prev + 12, 1) to (start + 1, 16)
 - Branch { true: Expression(0, Sub), false: Counter(2) } at (prev + 3, 9) to (start + 0, 16)
@@ -16,6 +15,5 @@ Number of file 0 mappings: 7
 - Code(Counter(2)) at (prev + 1, 9) to (start + 1, 15)
 - Code(Expression(0, Sub)) at (prev + 4, 5) to (start + 0, 11)
     = (c1 - c2)
-- Code(Expression(1, Add)) at (prev + 1, 1) to (start + 0, 2)
-    = (c2 + (c1 - c2))
+- Code(Counter(1)) at (prev + 1, 1) to (start + 0, 2)
 
diff --git a/tests/coverage/branch/while.cov-map b/tests/coverage/branch/while.cov-map
index 5a3ef096bed..fd05bbb69a5 100644
--- a/tests/coverage/branch/while.cov-map
+++ b/tests/coverage/branch/while.cov-map
@@ -1,42 +1,36 @@
 Function name: while::while_cond
-Raw bytes (42): 0x[01, 01, 03, 05, 09, 03, 09, 03, 09, 06, 01, 0c, 01, 01, 10, 05, 03, 09, 00, 12, 03, 01, 0b, 00, 10, 20, 09, 0a, 00, 0b, 00, 10, 09, 00, 11, 02, 06, 0a, 03, 01, 00, 02]
+Raw bytes (38): 0x[01, 01, 01, 05, 09, 06, 01, 0c, 01, 01, 10, 05, 03, 09, 00, 12, 03, 01, 0b, 00, 10, 20, 09, 05, 00, 0b, 00, 10, 09, 00, 11, 02, 06, 05, 03, 01, 00, 02]
 Number of files: 1
 - file 0 => global file 1
-Number of expressions: 3
+Number of expressions: 1
 - expression 0 operands: lhs = Counter(1), rhs = Counter(2)
-- expression 1 operands: lhs = Expression(0, Add), rhs = Counter(2)
-- expression 2 operands: lhs = Expression(0, Add), rhs = Counter(2)
 Number of file 0 mappings: 6
 - Code(Counter(0)) at (prev + 12, 1) to (start + 1, 16)
 - Code(Counter(1)) at (prev + 3, 9) to (start + 0, 18)
 - Code(Expression(0, Add)) at (prev + 1, 11) to (start + 0, 16)
     = (c1 + c2)
-- Branch { true: Counter(2), false: Expression(2, Sub) } at (prev + 0, 11) to (start + 0, 16)
+- Branch { true: Counter(2), false: Counter(1) } at (prev + 0, 11) to (start + 0, 16)
     true  = c2
-    false = ((c1 + c2) - c2)
+    false = c1
 - Code(Counter(2)) at (prev + 0, 17) to (start + 2, 6)
-- Code(Expression(2, Sub)) at (prev + 3, 1) to (start + 0, 2)
-    = ((c1 + c2) - c2)
+- Code(Counter(1)) at (prev + 3, 1) to (start + 0, 2)
 
 Function name: while::while_cond_not
-Raw bytes (42): 0x[01, 01, 03, 05, 09, 03, 09, 03, 09, 06, 01, 15, 01, 01, 10, 05, 03, 09, 00, 12, 03, 01, 0b, 00, 14, 20, 09, 0a, 00, 0b, 00, 14, 09, 00, 15, 02, 06, 0a, 03, 01, 00, 02]
+Raw bytes (38): 0x[01, 01, 01, 05, 09, 06, 01, 15, 01, 01, 10, 05, 03, 09, 00, 12, 03, 01, 0b, 00, 14, 20, 09, 05, 00, 0b, 00, 14, 09, 00, 15, 02, 06, 05, 03, 01, 00, 02]
 Number of files: 1
 - file 0 => global file 1
-Number of expressions: 3
+Number of expressions: 1
 - expression 0 operands: lhs = Counter(1), rhs = Counter(2)
-- expression 1 operands: lhs = Expression(0, Add), rhs = Counter(2)
-- expression 2 operands: lhs = Expression(0, Add), rhs = Counter(2)
 Number of file 0 mappings: 6
 - Code(Counter(0)) at (prev + 21, 1) to (start + 1, 16)
 - Code(Counter(1)) at (prev + 3, 9) to (start + 0, 18)
 - Code(Expression(0, Add)) at (prev + 1, 11) to (start + 0, 20)
     = (c1 + c2)
-- Branch { true: Counter(2), false: Expression(2, Sub) } at (prev + 0, 11) to (start + 0, 20)
+- Branch { true: Counter(2), false: Counter(1) } at (prev + 0, 11) to (start + 0, 20)
     true  = c2
-    false = ((c1 + c2) - c2)
+    false = c1
 - Code(Counter(2)) at (prev + 0, 21) to (start + 2, 6)
-- Code(Expression(2, Sub)) at (prev + 3, 1) to (start + 0, 2)
-    = ((c1 + c2) - c2)
+- Code(Counter(1)) at (prev + 3, 1) to (start + 0, 2)
 
 Function name: while::while_op_and
 Raw bytes (56): 0x[01, 01, 04, 05, 09, 03, 0d, 03, 0d, 11, 0d, 08, 01, 1e, 01, 01, 10, 05, 03, 09, 01, 12, 03, 02, 0b, 00, 10, 20, 0a, 0d, 00, 0b, 00, 10, 0a, 00, 14, 00, 19, 20, 09, 11, 00, 14, 00, 19, 09, 00, 1a, 03, 06, 0f, 04, 01, 00, 02]