feat!: Compress binary ECCs using zlib

Cargo.toml

@@ -67,3 +67,4 @@ typetag = "0.2.8"
 urlencoding = "2.1.2"
 webbrowser = "1.0.0"
 cool_asserts = "2.0.3"
+zstd = "0.13.2"

badger-optimiser/Cargo.toml

@@ -12,7 +12,11 @@ publish = false
 [dependencies]
 clap = { workspace = true, features = ["derive"] }
 serde_json = { workspace = true }
-tket2 = { path = "../tket2", features = ["portmatching", "rewrite-tracing"] }
+tket2 = { path = "../tket2", features = [
+    "portmatching",
+    "rewrite-tracing",
+    "binary-eccs",
+] }
 hugr = { workspace = true }
 itertools = { workspace = true }
 tket-json-rs = { workspace = true }

compile-rewriter/Cargo.toml

@@ -9,6 +9,6 @@ publish = false
 
 [dependencies]
 clap = { workspace = true, features = ["derive"] }
-tket2 = { path = "../tket2", features = ["portmatching"] }
+tket2 = { path = "../tket2", features = ["portmatching", "binary-eccs"] }
 hugr = { workspace = true }
 itertools = { workspace = true }

tket2-py/Cargo.toml

@@ -21,6 +21,7 @@ bench = false
 [dependencies]
 tket2 = { path = "../tket2", version = "0.1.0-alpha.1", features = [
     "portmatching",
+    "binary-eccs",
 ] }
 serde = { workspace = true, features = ["derive"] }
 serde_json = { workspace = true }

tket2/Cargo.toml

@@ -28,7 +28,10 @@ portmatching = ["dep:portmatching", "dep:rmp-serde"]
 # Stores a trace of the applied rewrites
 rewrite-tracing = []
 
-default = []
+# Support compressed binary encoded ECC files
+binary-eccs = ["dep:zstd"]
+
+default = ["binary-eccs"]
 
 [dependencies]
 lazy_static = { workspace = true }
@@ -62,6 +65,7 @@ chrono = { workspace = true }
 bytemuck = { workspace = true }
 crossbeam-channel = { workspace = true }
 tracing = { workspace = true }
+zstd = { workspace = true, optional = true }
 
 [dev-dependencies]
 rstest = { workspace = true }

tket2/src/optimiser/badger.rs

@@ -479,6 +479,7 @@ mod badger_default {
         }
 
         /// A sane default optimiser using a precompiled binary rewriter.
+        #[cfg(feature = "binary-eccs")]
         pub fn default_with_rewriter_binary(
             rewriter_path: impl AsRef<Path>,
         ) -> Result<Self, RewriterSerialisationError> {

tket2/src/rewrite/ecc_rewriter.rs

@@ -119,20 +119,24 @@ impl ECCRewriter {
     ///
     /// Precomputed rewriters can be serialised as binary and then loaded
     /// later using [`ECCRewriter::load_binary_io`].
+    #[cfg(feature = "binary-eccs")]
     pub fn save_binary_io<W: io::Write>(
         &self,
         writer: &mut W,
     ) -> Result<(), RewriterSerialisationError> {
-        rmp_serde::encode::write(writer, &self)?;
+        let mut encoder = zstd::Encoder::new(writer, 9)?;
+        rmp_serde::encode::write(&mut encoder, &self)?;
+        encoder.finish()?;
         Ok(())
     }
 
     /// Load a rewriter from an IO stream.
     ///
     /// Loads streams as created by [`ECCRewriter::save_binary_io`].
+    #[cfg(feature = "binary-eccs")]
     pub fn load_binary_io<R: io::Read>(reader: &mut R) -> Result<Self, RewriterSerialisationError> {
-        let matcher: Self = rmp_serde::decode::from_read(reader)?;
-        Ok(matcher)
+        let data = zstd::decode_all(reader)?;
+        Ok(rmp_serde::decode::from_slice(&data)?)
     }
 
     /// Save a rewriter as a binary file.
@@ -144,6 +148,7 @@ impl ECCRewriter {
     /// `.rwr`.
     ///
     /// If successful, returns the path to the newly created file.
+    #[cfg(feature = "binary-eccs")]
     pub fn save_binary(
         &self,
         name: impl AsRef<Path>,
@@ -157,10 +162,14 @@ impl ECCRewriter {
     }
 
     /// Loads a rewriter saved using [`ECCRewriter::save_binary`].
+    ///
+    /// Requires the `binary-eccs` feature to be enabled.
+    #[cfg(feature = "binary-eccs")]
     pub fn load_binary(name: impl AsRef<Path>) -> Result<Self, RewriterSerialisationError> {
-        let file = File::open(name)?;
-        let mut reader = std::io::BufReader::new(file);
-        Self::load_binary_io(&mut reader)
+        let mut file = File::open(name)?;
+        // Note: Buffering does not improve performance when using
+        // `zstd::decode_all`.
+        Self::load_binary_io(&mut file)
     }
 }