Move sr-arithmetic to a new crate and add in a fuzzer

Cargo.toml

@@ -53,6 +53,8 @@ members = [
 	"core/service/test",
 	"core/session",
 	"core/sr-api-macros",
+	"core/sr-arithmetic",
+	"core/sr-arithmetic/fuzzer",
 	"core/sr-io",
 	"core/sr-primitives",
 	"core/sr-staking-primitives",

core/sr-arithmetic/Cargo.toml

@@ -0,0 +1,26 @@
+[package]
+name = "sr-arithmetic"
+version = "2.0.0"
+authors = ["Parity Technologies <admin@parity.io>"]
+edition = "2018"
+
+[dependencies]
+num-traits = { version = "0.2.8", default-features = false }
+serde = { version = "1.0.101", optional = true, features = ["derive"] }
+codec = { package = "parity-scale-codec", version = "1.0.0", default-features = false, features = ["derive"] }
+rstd = { package = "sr-std", path = "../sr-std", default-features = false }
+integer-sqrt = "0.1.2"
+
+[dev-dependencies]
+primitive-types = "0.6.0"
+rand = "0.7.2"
+
+[features]
+bench = []
+default = ["std"]
+std = [
+	"serde",
+	"num-traits/std",
+	"rstd/std",
+	"codec/std",
+]

core/sr-arithmetic/fuzzer/.gitignore

@@ -0,0 +1,2 @@
+hfuzz_target
+hfuzz_workspace

core/sr-arithmetic/fuzzer/Cargo.toml

@@ -0,0 +1,20 @@
+[package]
+name = "sr-arithmetic-fuzzer"
+version = "2.0.0"
+authors = ["Parity Technologies <admin@parity.io>"]
+edition = "2018"
+
+[dependencies]
+sr-arithmetic = { path = ".." }
+honggfuzz = "0.5"
+primitive-types = "0.6"
+num-bigint = "0.2"
+num-traits = "0.2"
+
+[[bin]]
+name = "biguint"
+path = "src/biguint.rs"
+
+[[bin]]
+name = "rational128"
+path = "src/rational128.rs"