More optimizations and snapshot integration tests

rust_compiler/libs/optimizer/src/label_resolution.rs

@@ -0,0 +1,70 @@
+use il::{Instruction, InstructionNode, Operand};
+use rust_decimal::Decimal;
+use std::collections::HashMap;
+
+/// Pass: Resolve Labels
+/// Converts all Jump/Branch labels to absolute line numbers and removes LabelDefs.
+pub fn resolve_labels<'a>(input: Vec<InstructionNode<'a>>) -> Vec<InstructionNode<'a>> {
+    let mut label_map: HashMap<String, usize> = HashMap::new();
+    let mut line_number = 0;
+
+    // Build Label Map (filtering out LabelDefs from the count)
+    for node in &input {
+        if let Instruction::LabelDef(name) = &node.instruction {
+            label_map.insert(name.to_string(), line_number);
+        } else {
+            line_number += 1;
+        }
+    }
+
+    let mut output = Vec::with_capacity(input.len());
+
+    // Rewrite Jumps and Filter Labels
+    for mut node in input {
+        // Helper to get line number as Decimal operand
+        let get_line = |lbl: &Operand| -> Option<Operand<'a>> {
+            if let Operand::Label(name) = lbl {
+                label_map
+                    .get(name.as_ref())
+                    .map(|&l| Operand::Number(Decimal::from(l)))
+            } else {
+                None
+            }
+        };
+
+        match &mut node.instruction {
+            Instruction::LabelDef(_) => continue, // Strip labels
+
+            // Jumps
+            Instruction::Jump(op) => {
+                if let Some(num) = get_line(op) {
+                    *op = num;
+                }
+            }
+            Instruction::JumpAndLink(op) => {
+                if let Some(num) = get_line(op) {
+                    *op = num;
+                }
+            }
+            Instruction::BranchEq(_, _, op)
+            | Instruction::BranchNe(_, _, op)
+            | Instruction::BranchGt(_, _, op)
+            | Instruction::BranchLt(_, _, op)
+            | Instruction::BranchGe(_, _, op)
+            | Instruction::BranchLe(_, _, op) => {
+                if let Some(num) = get_line(op) {
+                    *op = num;
+                }
+            }
+            Instruction::BranchEqZero(_, op) | Instruction::BranchNeZero(_, op) => {
+                if let Some(num) = get_line(op) {
+                    *op = num;
+                }
+            }
+            _ => {}
+        }
+        output.push(node);
+    }
+
+    output
+}