Factored out test program and fuzzing features; core crate now only depends on smallvec and log.

test/Cargo.toml

@@ -0,0 +1,28 @@
+[package]
+name = "regalloc2-test"
+version = "0.0.1"
+authors = ["Chris Fallin <chris@cfallin.org>", "Mozilla SpiderMonkey Developers"]
+edition = "2018"
+license = "Apache-2.0 WITH LLVM-exception AND MPL-2.0"
+description = "small test driver for benchmarking regalloc2"
+repository = "https://github.com/bytecodealliance/regalloc2"
+
+[dependencies]
+regalloc2 = { version = "*", path = "../", features = ["fuzzing"] }
+
+# Keep this in sync with libfuzzer_sys's crate version:
+arbitrary = { version = "^0.4.6" }
+rand = { version = "0.8" }
+rand_chacha = { version = "0.3" }
+env_logger = { version = "*" }
+
+[dev-dependencies]
+criterion = "0.3"
+
+[profile.release]
+debug = true
+
+[[bench]]
+name = "regalloc"
+harness = false
+