chore: remove dead code from SSA optimization passes (#2800)

noir-lang · Sep 25, 2023 · 373325d · 373325d
1 parent feaf70e
commit 373325d
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Showing 4 changed files with 1 addition and 14 deletions.
diff --git a/compiler/noirc_evaluator/src/ssa/opt/flatten_cfg.rs b/compiler/noirc_evaluator/src/ssa/opt/flatten_cfg.rs
@@ -216,7 +216,6 @@ struct Branch {
     condition: ValueId,
     last_block: BasicBlockId,
     store_values: HashMap<ValueId, Store>,
-    local_allocations: HashSet<ValueId>,
 }
 
 fn flatten_function_cfg(function: &mut Function) {
@@ -661,7 +660,6 @@ impl<'f> Context<'f> {
                 // block arguments, it is safe to use the jmpif block here.
                 last_block: jmpif_block,
                 store_values: HashMap::default(),
-                local_allocations: HashSet::new(),
             }
         } else {
             self.push_condition(jmpif_block, new_condition);
@@ -685,13 +683,12 @@ impl<'f> Context<'f> {
             self.conditions.pop();
 
             let stores_in_branch = std::mem::replace(&mut self.store_values, old_stores);
-            let local_allocations = std::mem::replace(&mut self.local_allocations, old_allocations);
+            self.local_allocations = old_allocations;
 
             Branch {
                 condition: new_condition,
                 last_block: final_block,
                 store_values: stores_in_branch,
-                local_allocations,
             }
         }
     }

diff --git a/compiler/noirc_evaluator/src/ssa/opt/inlining.rs b/compiler/noirc_evaluator/src/ssa/opt/inlining.rs
@@ -88,9 +88,6 @@ struct PerFunctionContext<'function> {
     /// block.
     blocks: HashMap<BasicBlockId, BasicBlockId>,
 
-    /// Maps InstructionIds from the function being inlined to the function being inlined into.
-    instructions: HashMap<InstructionId, InstructionId>,
-
     /// True if we're currently working on the entry point function.
     inlining_entry: bool,
 }
@@ -191,7 +188,6 @@ impl<'function> PerFunctionContext<'function> {
             context,
             source_function,
             blocks: HashMap::default(),
-            instructions: HashMap::default(),
             values: HashMap::default(),
             inlining_entry: false,
         }

diff --git a/compiler/noirc_evaluator/src/ssa/opt/mem2reg.rs b/compiler/noirc_evaluator/src/ssa/opt/mem2reg.rs
@@ -70,7 +70,6 @@ use crate::ssa::{
     ir::{
         basic_block::BasicBlockId,
         cfg::ControlFlowGraph,
-        dom::DominatorTree,
         function::Function,
         function_inserter::FunctionInserter,
         instruction::{Instruction, InstructionId, TerminatorInstruction},
@@ -100,7 +99,6 @@ impl Ssa {
 struct PerFunctionContext<'f> {
     cfg: ControlFlowGraph,
     post_order: PostOrder,
-    dom_tree: DominatorTree,
 
     blocks: BTreeMap<BasicBlockId, Block>,
 
@@ -117,12 +115,10 @@ impl<'f> PerFunctionContext<'f> {
     fn new(function: &'f mut Function) -> Self {
         let cfg = ControlFlowGraph::with_function(function);
         let post_order = PostOrder::with_function(function);
-        let dom_tree = DominatorTree::with_cfg_and_post_order(&cfg, &post_order);
 
         PerFunctionContext {
             cfg,
             post_order,
-            dom_tree,
             inserter: FunctionInserter::new(function),
             blocks: BTreeMap::new(),
             instructions_to_remove: BTreeSet::new(),

diff --git a/compiler/noirc_evaluator/src/ssa/opt/unrolling.rs b/compiler/noirc_evaluator/src/ssa/opt/unrolling.rs
@@ -75,7 +75,6 @@ struct Loops {
     yet_to_unroll: Vec<Loop>,
     modified_blocks: HashSet<BasicBlockId>,
     cfg: ControlFlowGraph,
-    dom_tree: DominatorTree,
 }
 
 /// Find a loop in the program by finding a node that dominates any predecessor node.
@@ -109,7 +108,6 @@ fn find_all_loops(function: &Function) -> Loops {
         yet_to_unroll: loops,
         modified_blocks: HashSet::new(),
         cfg,
-        dom_tree,
     }
 }