From 825258939bee841a3715edf6e2a1fb8a95a4d1cc Mon Sep 17 00:00:00 2001
From: Nick Fitzgerald <fitzgen@gmail.com>
Date: Tue, 28 Sep 2021 15:54:01 -0700
Subject: [PATCH] Define a fuzz target for the parser

---
 cranelift/isle/Cargo.lock                 | 25 +++++++++++++++++++++++
 cranelift/isle/Cargo.toml                 |  6 +++++-
 cranelift/isle/fuzz/.gitignore            |  3 +++
 cranelift/isle/fuzz/Cargo.toml            | 19 +++++++++++++++++
 cranelift/isle/fuzz/fuzz_targets/parse.rs |  9 ++++++++
 5 files changed, 61 insertions(+), 1 deletion(-)
 create mode 100644 cranelift/isle/fuzz/.gitignore
 create mode 100644 cranelift/isle/fuzz/Cargo.toml
 create mode 100644 cranelift/isle/fuzz/fuzz_targets/parse.rs

diff --git a/cranelift/isle/Cargo.lock b/cranelift/isle/Cargo.lock
index 08c529adf6..6a0f0849c0 100644
--- a/cranelift/isle/Cargo.lock
+++ b/cranelift/isle/Cargo.lock
@@ -35,6 +35,12 @@ dependencies = [
  "winapi",
 ]
 
+[[package]]
+name = "arbitrary"
+version = "1.0.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "577b08a4acd7b99869f863c50011b01eb73424ccc798ecd996f2e24817adfca7"
+
 [[package]]
 name = "atty"
 version = "0.2.14"
@@ -148,6 +154,14 @@ dependencies = [
  "thiserror",
 ]
 
+[[package]]
+name = "isle-fuzz"
+version = "0.0.0"
+dependencies = [
+ "isle",
+ "libfuzzer-sys",
+]
+
 [[package]]
 name = "islec"
 version = "0.1.0"
@@ -171,6 +185,17 @@ version = "0.2.101"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "3cb00336871be5ed2c8ed44b60ae9959dc5b9f08539422ed43f09e34ecaeba21"
 
+[[package]]
+name = "libfuzzer-sys"
+version = "0.4.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "36a9a84a6e8b55dfefb04235e55edb2b9a2a18488fcae777a6bdaa6f06f1deb3"
+dependencies = [
+ "arbitrary",
+ "cc",
+ "once_cell",
+]
+
 [[package]]
 name = "log"
 version = "0.4.14"
diff --git a/cranelift/isle/Cargo.toml b/cranelift/isle/Cargo.toml
index 2f3fcbb680..d1cf4b88ec 100644
--- a/cranelift/isle/Cargo.toml
+++ b/cranelift/isle/Cargo.toml
@@ -1,2 +1,6 @@
 [workspace]
-members = [ "isle", "islec" ]
+members = [
+  "./fuzz",
+  "./isle",
+  "./islec",
+]
diff --git a/cranelift/isle/fuzz/.gitignore b/cranelift/isle/fuzz/.gitignore
new file mode 100644
index 0000000000..a0925114d6
--- /dev/null
+++ b/cranelift/isle/fuzz/.gitignore
@@ -0,0 +1,3 @@
+target
+corpus
+artifacts
diff --git a/cranelift/isle/fuzz/Cargo.toml b/cranelift/isle/fuzz/Cargo.toml
new file mode 100644
index 0000000000..dbfb2ddb9a
--- /dev/null
+++ b/cranelift/isle/fuzz/Cargo.toml
@@ -0,0 +1,19 @@
+[package]
+name = "isle-fuzz"
+version = "0.0.0"
+authors = ["Automatically generated"]
+publish = false
+edition = "2018"
+
+[package.metadata]
+cargo-fuzz = true
+
+[dependencies]
+isle = { path = "../isle" }
+libfuzzer-sys = "0.4"
+
+[[bin]]
+name = "parse"
+path = "fuzz_targets/parse.rs"
+test = false
+doc = false
diff --git a/cranelift/isle/fuzz/fuzz_targets/parse.rs b/cranelift/isle/fuzz/fuzz_targets/parse.rs
new file mode 100644
index 0000000000..f2a572dbd7
--- /dev/null
+++ b/cranelift/isle/fuzz/fuzz_targets/parse.rs
@@ -0,0 +1,9 @@
+#![no_main]
+
+use libfuzzer_sys::fuzz_target;
+
+fuzz_target!(|s: &str| {
+    let lexer = isle::lexer::Lexer::from_str(s, "fuzz-input.isle");
+    let mut parser = isle::parser::Parser::new(lexer);
+    let _ = parser.parse_defs();
+});