Fix clippy warnings

Author: antoyo

.github/workflows/ci.yml

@@ -23,7 +23,10 @@ jobs:
       run: sudo apt-get install nasm
 
     - name: Setup Rust
-      run: rustup update ${{ matrix.toolchain }} && rustup default ${{ matrix.toolchain }}
+      run: |
+        rustup update ${{ matrix.toolchain }}
+        rustup default ${{ matrix.toolchain }}
+        rustup component add clippy
 
     - name: Compile
       run: |
@@ -34,3 +37,8 @@ jobs:
       run: |
         cd tiger
         cargo test
+
+    - name: Clippy
+      run: |
+        cd tiger
+        cargo clippy --all-targets -- -D warnings

tiger/.cargo/config tiger/.cargo/config.tomltiger/.cargo/config renamed to tiger/.cargo/config.toml

@@ -23,6 +23,7 @@ use position::WithPos;
 use symbol::{Symbol, SymbolWithPos};
 use temp::Label;
 
+#[allow(clippy::enum_variant_names)]
 #[derive(Clone, Debug, PartialEq)]
 pub enum Declaration {
     ClassDeclaration {

tiger/src/ast.rs

@@ -101,7 +101,7 @@ pub fn basic_blocks(statements: Vec<Statement>) -> (Vec<Vec<Statement>>, Label)
 
 pub fn trace_schedule(mut basic_blocks: Vec<Vec<Statement>>, done_label: Label) -> Vec<Statement> {
     let mut label_mapping = HashMap::new();
-    label_mapping.insert(&done_label, usize::max_value());
+    label_mapping.insert(&done_label, usize::MAX);
     for (index, basic_block) in basic_blocks.iter().enumerate() {
         match basic_block.first().expect("at least one statement in basic block").statement {
             _Statement::Label(ref label) => {
@@ -149,7 +149,7 @@ pub fn trace_schedule(mut basic_blocks: Vec<Vec<Statement>>, done_label: Label)
 
     for trace in traces {
         for index in trace {
-            let trace_statements = mem::replace(&mut basic_blocks[index], vec![]);
+            let trace_statements = mem::take(&mut basic_blocks[index]);
             for statement in trace_statements {
                 statements.push_back(statement);
             }
@@ -212,7 +212,7 @@ pub fn trace_schedule(mut basic_blocks: Vec<Vec<Statement>>, done_label: Label)
                 match expr {
                     Exp::Name(label) => {
                         if labels.len() == 1 && labels[0] == label {
-                            if let Some(ref statement) = statements.front() {
+                            if let Some(statement) = statements.front() {
                                 if let _Statement::Label(ref next_label) = statement.statement {
                                     if next_label == &label {
                                         // Remove unconditional jumps to next statement.

tiger/src/canon.rs

@@ -128,7 +128,7 @@ impl EscapeFinder {
                 self.visit_exp(test, depth);
                 self.visit_exp(then, depth);
                 if let Some(ref else_) = *else_ {
-                    self.visit_exp(&else_, depth);
+                    self.visit_exp(else_, depth);
                 }
             },
             Expr::Int { .. } => (),

tiger/src/escape.rs

@@ -33,7 +33,8 @@ pub struct Node {
     pub stack_uses: BTreeSet<i64>,
     pub uses: BTreeSet<Temp>,
     pub return_label: Option<Label>,
-    pub is_move: bool,
+    // TODO: This field is unused. Check out if it's really not needed.
+    //pub is_move: bool,
 }
 
 pub struct FlowGraph {
@@ -53,6 +54,7 @@ struct GraphBuilder<'a> {
     visited: HashMap<usize, Entry>,
 }
 
+#[allow(clippy::needless_lifetimes)]
 impl<'a> GraphBuilder<'a> {
     fn build(&mut self, current_index: usize, predecessor: Option<Entry>) {
         if let Some(&entry) = self.visited.get(&current_index) {
@@ -68,11 +70,12 @@ impl<'a> GraphBuilder<'a> {
                 Instruction::Call { ref return_label, .. } => Some(return_label.clone()),
                 _ => None,
             };
-        let is_move =
+        // TODO: This is unused. Check out if it's really not needed.
+        /*let is_move =
             match *instruction {
                 Instruction::Move { .. } => true,
                 _ => false,
-            };
+            };*/
         let defines =
             match *instruction {
                 Instruction::Call { ref destination, .. } | Instruction::Move { ref destination, .. } | Instruction::Operation { ref destination, .. } =>
@@ -104,7 +107,7 @@ impl<'a> GraphBuilder<'a> {
             stack_defines,
             stack_uses,
             uses,
-            is_move,
+            //is_move,
         };
         let entry = self.control_flow_graph.insert(node);
         self.visited.insert(current_index, entry);

tiger/src/flow.rs

@@ -57,7 +57,8 @@ pub trait Frame: Clone {
     const WORD_SIZE: i64;
 
     fn registers() -> Vec<Temp>;
-    fn register_count() -> usize;
+    // TODO: This is not used. Check if this is really not needed.
+    //fn register_count() -> usize;
     fn temp_map() -> HashMap<Temp, &'static str>;
     fn special_name(temp: Temp) -> Option<&'static str>;
 

tiger/src/frame/mod.rs

@@ -232,9 +232,10 @@ impl Frame for X86_64 {
         registers
     }
 
-    fn register_count() -> usize {
+    // TODO: This is not used. Check if this is really not needed.
+    /*fn register_count() -> usize {
         Self::registers().len() - [Self::rsp(), Self::rbp()].len()
-    }
+    }*/
 
     fn temp_map() -> HashMap<Temp, &'static str> {
         let mut map = HashMap::new();

tiger/src/frame/x86_64.rs

@@ -23,6 +23,7 @@
 
 use temp::{Label, Temp};
 
+#[allow(clippy::enum_variant_names)]
 #[derive(Clone, Debug, PartialEq)]
 pub enum Exp {
     Const(i64),

tiger/src/ir.rs

@@ -151,7 +151,7 @@ impl<R: Read> Lexer<R> {
                 't' => '\t',
                 '\\' => '\\',
                 '"' => '"',
-                ch if ch.is_digit(10) => return self.escape_ascii_code(pos),
+                ch if ch.is_ascii_digit() => return self.escape_ascii_code(pos),
                 escape => {
                     pos.length = 2;
                     return Err(InvalidEscape {