chore: pull value merger code from sync (#10080)

Please read [contributing guidelines](CONTRIBUTING.md) and remove this
line.

Author: TomAFrench

barretenberg/cpp/src/barretenberg/bb/main.cpp

@@ -136,7 +136,7 @@ std::string honk_vk_to_json(std::vector<bb::fr>& data)
 }
 
 /**
- * @brief Proves and Verifies an ACIR circuit
+ * @brief Proves and verifies an ACIR circuit
  *
  * Communication:
  * - proc_exit: A boolean value is returned indicating whether the proof is valid.

noir/noir-repo/compiler/noirc_evaluator/src/ssa/ir/instruction.rs

@@ -272,12 +272,7 @@ pub(crate) enum Instruction {
     ///
     /// Where we save the result of !then_condition so that we have the same
     /// ValueId for it each time.
-    IfElse {
-        then_condition: ValueId,
-        then_value: ValueId,
-        else_condition: ValueId,
-        else_value: ValueId,
-    },
+    IfElse { then_condition: ValueId, then_value: ValueId, else_value: ValueId },
 
     /// Creates a new array or slice.
     ///
@@ -524,14 +519,11 @@ impl Instruction {
                     assert_message: assert_message.clone(),
                 }
             }
-            Instruction::IfElse { then_condition, then_value, else_condition, else_value } => {
-                Instruction::IfElse {
-                    then_condition: f(*then_condition),
-                    then_value: f(*then_value),
-                    else_condition: f(*else_condition),
-                    else_value: f(*else_value),
-                }
-            }
+            Instruction::IfElse { then_condition, then_value, else_value } => Instruction::IfElse {
+                then_condition: f(*then_condition),
+                then_value: f(*then_value),
+                else_value: f(*else_value),
+            },
             Instruction::MakeArray { elements, typ } => Instruction::MakeArray {
                 elements: elements.iter().copied().map(f).collect(),
                 typ: typ.clone(),
@@ -590,10 +582,9 @@ impl Instruction {
             | Instruction::RangeCheck { value, .. } => {
                 f(*value);
             }
-            Instruction::IfElse { then_condition, then_value, else_condition, else_value } => {
+            Instruction::IfElse { then_condition, then_value, else_value } => {
                 f(*then_condition);
                 f(*then_value);
-                f(*else_condition);
                 f(*else_value);
             }
             Instruction::MakeArray { elements, typ: _ } => {
@@ -756,7 +747,7 @@ impl Instruction {
                     None
                 }
             }
-            Instruction::IfElse { then_condition, then_value, else_condition, else_value } => {
+            Instruction::IfElse { then_condition, then_value, else_value } => {
                 let typ = dfg.type_of_value(*then_value);
 
                 if let Some(constant) = dfg.get_numeric_constant(*then_condition) {
@@ -775,13 +766,11 @@ impl Instruction {
 
                 if matches!(&typ, Type::Numeric(_)) {
                     let then_condition = *then_condition;
-                    let else_condition = *else_condition;
 
                     let result = ValueMerger::merge_numeric_values(
                         dfg,
                         block,
                         then_condition,
-                        else_condition,
                         then_value,
                         else_value,
                     );

noir/noir-repo/compiler/noirc_evaluator/src/ssa/ir/instruction/call.rs

@@ -443,12 +443,8 @@ fn simplify_slice_push_back(
     let mut value_merger =
         ValueMerger::new(dfg, block, &mut slice_sizes, unknown, None, call_stack);
 
-    let new_slice = value_merger.merge_values(
-        len_not_equals_capacity,
-        len_equals_capacity,
-        set_last_slice_value,
-        new_slice,
-    );
+    let new_slice =
+        value_merger.merge_values(len_not_equals_capacity, set_last_slice_value, new_slice);
 
     SimplifyResult::SimplifiedToMultiple(vec![new_slice_length, new_slice])
 }

noir/noir-repo/compiler/noirc_evaluator/src/ssa/ir/printer.rs

@@ -209,15 +209,11 @@ fn display_instruction_inner(
         Instruction::RangeCheck { value, max_bit_size, .. } => {
             writeln!(f, "range_check {} to {} bits", show(*value), *max_bit_size,)
         }
-        Instruction::IfElse { then_condition, then_value, else_condition, else_value } => {
+        Instruction::IfElse { then_condition, then_value, else_value } => {
             let then_condition = show(*then_condition);
             let then_value = show(*then_value);
-            let else_condition = show(*else_condition);
             let else_value = show(*else_value);
-            writeln!(
-                f,
-                "if {then_condition} then {then_value} else if {else_condition} then {else_value}"
-            )
+            writeln!(f, "if {then_condition} then {then_value} else {else_value}")
         }
         Instruction::MakeArray { elements, typ } => {
             write!(f, "make_array [")?;