feat!: Compress binary ECCs using zlib (#498)

Breaking change for the compiled `.rwr` ECC sets. The format is now
compressed using `zstd`.

Comparative figures for the `nam_6_3.rwr` included in the python
package:

- File size reduced from `69MB` to `4.4MB`.
- Load time on my machine reduced from `~560ms` to `~420ms`.
- (offline) ECC compilation time increased from `2.4s` to `3s`.
This is using the highest compression rate. Faster encodings produce
files of around `5MB`.

Closes #488

BREAKING CHANGE: `.rwr` ECC files generated with older versions are no
longer supported. Please recompile them, or compress the file with
`zstd`.

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 }

badger-optimiser/src/main.rs

@@ -140,11 +140,15 @@ fn main() -> Result<(), Box<dyn std::error::Error>> {
         circ.enable_rewrite_tracing();
     }
 
-    println!("Loading optimiser...");
+    print!("Loading optimiser...");
+    let load_ecc_start = std::time::Instant::now();
     let Ok(optimiser) = load_optimiser(ecc_path) else {
+        println!();
         eprintln!("Unable to load ECC file {ecc_path:?}. Is it a JSON file of Quartz-generated ECCs? Or a pre-compiled `.rwr` ECC set?");
         exit(1);
     };
+    println!(" done in {:?}", load_ecc_start.elapsed());
+
     println!(
         "Using {n_threads} threads. Queue size is {}.",
         opts.queue_size

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 }

compile-rewriter/src/main.rs

@@ -52,13 +52,16 @@ fn main() {
         );
         exit(1);
     };
-    println!("Saving to file...");
+    print!("Saving to file...");
     let output_file = if output_path.is_dir() {
         output_path.join("matcher.rwr")
     } else {
         output_path.to_path_buf()
     };
+    let write_time = Instant::now();
     let output_file = rewriter.save_binary(output_file).unwrap();
+    println!(" done in {:?}", write_time.elapsed());
+
     println!("Written rewriter to {:?}", output_file);
 
     // Print the file size of output_file in megabytes

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> {