Add support for some serde serialization (#847)

* Add support for some serde serialization

cranelift/codegen/src/ir/entities.rs

@@ -22,6 +22,8 @@
 use crate::entity::entity_impl;
 use core::fmt;
 use core::u32;
+#[cfg(feature = "enable-serde")]
+use serde::{Deserialize, Serialize};
 
 /// An opaque reference to an extended basic block in a function.
 #[derive(Copy, Clone, PartialEq, Eq, Hash, PartialOrd, Ord)]
@@ -103,6 +105,7 @@ impl GlobalValue {
 
 /// An opaque reference to a jump table.
 #[derive(Copy, Clone, PartialEq, Eq, Hash)]
+#[cfg_attr(feature = "enable-serde", derive(Serialize, Deserialize))]
 pub struct JumpTable(u32);
 entity_impl!(JumpTable, "jt");
 

cranelift/codegen/src/ir/libcall.rs

@@ -7,6 +7,8 @@ use crate::ir::{
 use crate::isa::{CallConv, RegUnit, TargetIsa};
 use core::fmt;
 use core::str::FromStr;
+#[cfg(feature = "enable-serde")]
+use serde::{Deserialize, Serialize};
 
 /// The name of a runtime library routine.
 ///
@@ -17,6 +19,7 @@ use core::str::FromStr;
 ///
 /// This list is likely to grow over time.
 #[derive(Copy, Clone, Debug, PartialEq, Eq)]
+#[cfg_attr(feature = "enable-serde", derive(Serialize, Deserialize))]
 pub enum LibCall {
     /// probe for stack overflow. These are emitted for functions which need
     /// when the `probestack_enabled` setting is true.

cranelift/codegen/src/ir/sourceloc.rs

@@ -4,6 +4,8 @@
 //! location when instructions are transformed.
 
 use core::fmt;
+#[cfg(feature = "enable-serde")]
+use serde::{Deserialize, Serialize};
 
 /// A source location.
 ///
@@ -13,6 +15,7 @@ use core::fmt;
 /// The default source location uses the all-ones bit pattern `!0`. It is used for instructions
 /// that can't be given a real source location.
 #[derive(Clone, Copy, Debug, PartialEq, Eq)]
+#[cfg_attr(feature = "enable-serde", derive(Serialize, Deserialize))]
 pub struct SourceLoc(u32);
 
 impl SourceLoc {