Add a ValueLoc type and the locations table.

This table holds the result of register allocation.

lib/cretonne/src/ir/mod.rs

@@ -13,6 +13,7 @@ pub mod function;
 mod funcname;
 mod extfunc;
 mod builder;
+mod valueloc;
 
 pub use ir::funcname::FunctionName;
 pub use ir::extfunc::{Signature, ArgumentType, ArgumentExtension, ExtFuncData};
@@ -21,6 +22,7 @@ pub use ir::entities::{Ebb, Inst, Value, StackSlot, JumpTable, FuncRef, SigRef};
 pub use ir::instructions::{Opcode, InstructionData, VariableArgs};
 pub use ir::stackslot::StackSlotData;
 pub use ir::jumptable::JumpTableData;
+pub use ir::valueloc::ValueLoc;
 pub use ir::dfg::{DataFlowGraph, ValueDef};
 pub use ir::layout::{Layout, Cursor};
 pub use ir::function::Function;