Use an EntityMap for stack slots.

Delete the StackSlots iterator and move the remaining StackSlotData into its
own module.

cranelift/src/libcretonne/ir/mod.rs

@@ -1,10 +1,11 @@
 //! Representation of Cretonne IL functions.
 
-pub mod entities;
 pub mod types;
+pub mod entities;
 pub mod condcodes;
 pub mod immediates;
 pub mod instructions;
+pub mod stackslot;
 pub mod jumptable;
 pub mod dfg;
 pub mod layout;
@@ -12,13 +13,13 @@ pub mod layout;
 pub use ir::types::{Type, FunctionName, Signature};
 pub use ir::entities::{Ebb, Inst, Value, StackSlot, JumpTable};
 pub use ir::instructions::{Opcode, InstructionData};
+pub use ir::stackslot::StackSlotData;
+pub use ir::jumptable::JumpTableData;
 pub use ir::dfg::DataFlowGraph;
 pub use ir::layout::Layout;
 
-use ir::jumptable::JumpTableData;
-use std::fmt::{self, Debug, Display, Formatter};
-use std::ops::Index;
-use entity_map::{EntityRef, EntityMap, PrimaryEntityData};
+use std::fmt::{self, Debug, Formatter};
+use entity_map::{EntityMap, PrimaryEntityData};
 
 /// A function.
 pub struct Function {
@@ -29,7 +30,7 @@ pub struct Function {
     signature: Signature,
 
     /// Stack slots allocated in this function.
-    stack_slots: Vec<StackSlotData>,
+    pub stack_slots: EntityMap<StackSlot, StackSlotData>,
 
     /// Jump tables used in this function.
     pub jump_tables: EntityMap<JumpTable, JumpTableData>,
@@ -41,7 +42,7 @@ pub struct Function {
     pub layout: Layout,
 }
 
-// Tag JumpTableData as a primary entity so jump_tables above .
+impl PrimaryEntityData for StackSlotData {}
 impl PrimaryEntityData for JumpTableData {}
 
 impl Function {
@@ -50,7 +51,7 @@ impl Function {
         Function {
             name: name,
             signature: sig,
-            stack_slots: Vec::new(),
+            stack_slots: EntityMap::new(),
             jump_tables: EntityMap::new(),
             dfg: DataFlowGraph::new(),
             layout: Layout::new(),
@@ -66,23 +67,6 @@ impl Function {
     pub fn own_signature(&self) -> &Signature {
         &self.signature
     }
-
-    // Stack slots.
-
-    /// Allocate a new stack slot.
-    pub fn make_stack_slot(&mut self, data: StackSlotData) -> StackSlot {
-        let ss = StackSlot::new(self.stack_slots.len());
-        self.stack_slots.push(data);
-        ss
-    }
-
-    /// Iterate over all stack slots in function.
-    pub fn stack_slot_iter(&self) -> StackSlotIter {
-        StackSlotIter {
-            cur: 0,
-            end: self.stack_slots.len(),
-        }
-    }
 }
 
 impl Debug for Function {
@@ -91,76 +75,3 @@ impl Debug for Function {
         fmt.write_str(&function_to_string(self))
     }
 }
-
-// ====--------------------------------------------------------------------------------------====//
-//
-// Stack slot implementation.
-//
-// ====--------------------------------------------------------------------------------------====//
-
-/// Contents of a stack slot.
-#[derive(Debug)]
-pub struct StackSlotData {
-    /// Size of stack slot in bytes.
-    pub size: u32,
-}
-
-impl StackSlotData {
-    /// Create a stack slot with the specified byte size.
-    pub fn new(size: u32) -> StackSlotData {
-        StackSlotData { size: size }
-    }
-}
-
-impl Display for StackSlotData {
-    fn fmt(&self, fmt: &mut Formatter) -> fmt::Result {
-        write!(fmt, "stack_slot {}", self.size)
-    }
-}
-
-/// Allow immutable access to stack slots via function indexing.
-impl Index<StackSlot> for Function {
-    type Output = StackSlotData;
-
-    fn index<'a>(&'a self, ss: StackSlot) -> &'a StackSlotData {
-        &self.stack_slots[ss.index()]
-    }
-}
-
-/// Stack slot iterator visits all stack slots in a function, returning `StackSlot` references.
-pub struct StackSlotIter {
-    cur: usize,
-    end: usize,
-}
-
-impl Iterator for StackSlotIter {
-    type Item = StackSlot;
-
-    fn next(&mut self) -> Option<Self::Item> {
-        if self.cur < self.end {
-            let ss = StackSlot::new(self.cur);
-            self.cur += 1;
-            Some(ss)
-        } else {
-            None
-        }
-    }
-}
-
-#[cfg(test)]
-mod tests {
-    use super::*;
-
-    #[test]
-    fn stack_slot() {
-        let mut func = Function::new();
-
-        let ss0 = func.make_stack_slot(StackSlotData::new(4));
-        let ss1 = func.make_stack_slot(StackSlotData::new(8));
-        assert_eq!(ss0.to_string(), "ss0");
-        assert_eq!(ss1.to_string(), "ss1");
-
-        assert_eq!(func[ss0].size, 4);
-        assert_eq!(func[ss1].size, 8);
-    }
-}

cranelift/src/libcretonne/ir/stackslot.rs

@@ -0,0 +1,45 @@
+//! Stack slots.
+//!
+//! The `StackSlotData` struct keeps track of a single stack slot in a function.
+//!
+
+use std::fmt::{self, Display, Formatter};
+
+/// Contents of a stack slot.
+#[derive(Debug)]
+pub struct StackSlotData {
+    /// Size of stack slot in bytes.
+    pub size: u32,
+}
+
+impl StackSlotData {
+    /// Create a stack slot with the specified byte size.
+    pub fn new(size: u32) -> StackSlotData {
+        StackSlotData { size: size }
+    }
+}
+
+impl Display for StackSlotData {
+    fn fmt(&self, fmt: &mut Formatter) -> fmt::Result {
+        write!(fmt, "stack_slot {}", self.size)
+    }
+}
+
+#[cfg(test)]
+mod tests {
+    use ir::Function;
+    use super::StackSlotData;
+
+    #[test]
+    fn stack_slot() {
+        let mut func = Function::new();
+
+        let ss0 = func.stack_slots.push(StackSlotData::new(4));
+        let ss1 = func.stack_slots.push(StackSlotData::new(8));
+        assert_eq!(ss0.to_string(), "ss0");
+        assert_eq!(ss1.to_string(), "ss1");
+
+        assert_eq!(func.stack_slots[ss0].size, 4);
+        assert_eq!(func.stack_slots[ss1].size, 8);
+    }
+}

cranelift/src/libcretonne/write.rs

@@ -68,9 +68,9 @@ fn write_spec(w: &mut Write, func: &Function) -> Result {
 fn write_preamble(w: &mut Write, func: &Function) -> io::Result<bool> {
     let mut any = false;
 
-    for ss in func.stack_slot_iter() {
+    for ss in func.stack_slots.keys() {
         any = true;
-        try!(writeln!(w, "    {} = {}", ss, func[ss]));
+        try!(writeln!(w, "    {} = {}", ss, func.stack_slots[ss]));
     }
 
     for jt in func.jump_tables.keys() {
@@ -249,7 +249,7 @@ mod tests {
         f.name.push_str("foo");
         assert_eq!(function_to_string(&f), "function foo() {\n}\n");
 
-        f.make_stack_slot(StackSlotData::new(4));
+        f.stack_slots.push(StackSlotData::new(4));
         assert_eq!(function_to_string(&f),
                    "function foo() {\n    ss0 = stack_slot 4\n}\n");
 

cranelift/src/libreader/parser.rs

@@ -11,14 +11,13 @@ use std::fmt::{self, Display, Formatter};
 use std::str::FromStr;
 use std::u32;
 use lexer::{self, Lexer, Token};
-use cretonne::ir::{Function, Ebb, Inst, Opcode, Value, Type, FunctionName, StackSlotData,
-                   JumpTable, StackSlot};
+use cretonne::ir::{Function, Ebb, Inst, Opcode, Value, Type, FunctionName, StackSlot,
+                   StackSlotData, JumpTable, JumpTableData};
 use cretonne::ir::types::{VOID, Signature, ArgumentType, ArgumentExtension};
 use cretonne::ir::immediates::{Imm64, Ieee32, Ieee64};
 use cretonne::ir::entities::{NO_EBB, NO_VALUE};
 use cretonne::ir::instructions::{InstructionFormat, InstructionData, VariableArgs, JumpData,
                                  BranchData, ReturnData};
-use cretonne::ir::jumptable::JumpTableData;
 
 pub use lexer::Location;
 
@@ -95,7 +94,7 @@ impl Context {
 
     // Allocate a new stack slot and add a mapping number -> StackSlot.
     fn add_ss(&mut self, number: u32, data: StackSlotData, loc: &Location) -> Result<()> {
-        if self.stack_slots.insert(number, self.function.make_stack_slot(data)).is_some() {
+        if self.stack_slots.insert(number, self.function.stack_slots.push(data)).is_some() {
             err!(loc, "duplicate stack slot: ss{}", number)
         } else {
             Ok(())
@@ -1173,13 +1172,13 @@ mod tests {
             .parse_function()
             .unwrap();
         assert_eq!(func.name, "foo");
-        let mut iter = func.stack_slot_iter();
+        let mut iter = func.stack_slots.keys();
         let ss0 = iter.next().unwrap();
         assert_eq!(ss0.to_string(), "ss0");
-        assert_eq!(func[ss0].size, 13);
+        assert_eq!(func.stack_slots[ss0].size, 13);
         let ss1 = iter.next().unwrap();
         assert_eq!(ss1.to_string(), "ss1");
-        assert_eq!(func[ss1].size, 1);
+        assert_eq!(func.stack_slots[ss1].size, 1);
         assert_eq!(iter.next(), None);
 
         // Catch duplicate definitions.