fix: hoist constraints on inputs to top of program

compiler/noirc_evaluator/src/ssa/opt/bubble_up_constrains.rs

@@ -30,7 +30,7 @@ impl Ssa {
                         // We iterate through the previous instructions in reverse order so the index is from the
                         // back of the vector. Subtract from vector length to get correct index.
                         .map(|reversed_index| filtered_instructions.len() - reversed_index)
-                        .unwrap_or(filtered_instructions.len());
+                        .unwrap_or(0);
 
                     filtered_instructions.insert(index, instruction);
                 }

test_programs/execution_success/bit_and/Prover.toml

@@ -1,2 +1,4 @@
 x = "0x00"
 y = "0x10"
+a = "0x00"
+b = "0x10"

test_programs/execution_success/bit_and/src/main.nr

@@ -1,6 +1,6 @@
 // You can only do bit operations with integers.
 // (Kobi/Daira/Circom/#37) https://github.com/iden3/circom/issues/37
-fn main(x: Field, y: Field) {
+fn main(x: Field, y: Field, a: Field, b: Field) {
     let x_as_u8 = x as u8;
     let y_as_u8 = y as u8;
 
@@ -9,8 +9,8 @@ fn main(x: Field, y: Field) {
     let flag = (x == 0) & (y == 16);
     assert(flag);
     //bitwise and with odd bits:
-    let x_as_u11 = x as u11;
-    let y_as_u11 = y as u11;
-    assert((x_as_u11 & y_as_u11) == x_as_u11);
+    let a_as_u8 = a as u8;
+    let b_as_u8 = b as u8;
+    assert((a_as_u8 & b_as_u8) == a_as_u8);
 }