cranelift-fuzzgen: Consume all trailing fuzz input
But don't keep going once we've consumed it all.
@@ -137,11 +137,12 @@ where
})
}
- fn generate_test_inputs(&mut self, signature: &Signature) -> Result<Vec<TestCaseInput>> {
- let num_tests = self.u.int_in_range(self.config.test_case_inputs.clone())?;
- let mut inputs = Vec::with_capacity(num_tests);
+ fn generate_test_inputs(mut self, signature: &Signature) -> Result<Vec<TestCaseInput>> {
+ let mut inputs = Vec::new();
+
+ loop {
+ let last_len = self.u.len();
- for _ in 0..num_tests {
let test_args = signature
.params
.iter()
@@ -149,6 +150,17 @@ where
.collect::<Result<TestCaseInput>>()?;
inputs.push(test_args);
+
+ // Continue generating input as long as we just consumed some of self.u. Otherwise
+ // we'll generate the same test input again and again, forever. Note that once self.u
+ // becomes empty we obviously can't consume any more of it, so this check is more
+ // general. Also note that we need to generate at least one input or the fuzz target
+ // won't actually test anything, so checking at the end of the loop is good, even if
+ // self.u is empty from the start and we end up with all zeros in test_args.
+ assert!(self.u.len() <= last_len);
+ if self.u.len() == last_len {
+ break;
+ }
}
Ok(inputs)
