fallback to systemtime on non-x86

Author: domenukk

fuzzers/libfuzzer_libpng/Makefile

@@ -18,6 +18,14 @@ run: all
 	sleep 0.2
 	./$(FUZZER_NAME) >/dev/null 2>/dev/null &
 
+short_test: all
+	timeout 11s ./$(FUZZER_NAME) &
+	sleep 0.2
+	timeout 10s taskset -c 0 ./$(FUZZER_NAME) >/dev/null 2>/dev/null &
+	timeout 10s taskset -c 1 ./$(FUZZER_NAME) >/dev/null 2>/dev/null &
+	timeout 10s taskset -c 2 ./$(FUZZER_NAME) >/dev/null 2>/dev/null &
+	timeout 10s taskset -c 3 ./$(FUZZER_NAME) >/dev/null 2>/dev/null &
+
 test: all
 	timeout 60s ./$(FUZZER_NAME) &
 	sleep 0.2

libafl/src/cpu.rs

@@ -1,12 +1,31 @@
 //! Architecture agnostic processor features
 
-/// Read time counter using [`llvmint::readcyclecounter`]
+#[cfg(not(any(target_arch = "x86_64", target_arch = "x86")))]
+use crate::utils::current_nanos;
+
+// TODO: Add more architectures, using C code, see
+// https://github.com/google/benchmark/blob/master/src/cycleclock.h
+// Or using llvm intrinsics (if they ever should become available in stable rust?)
+
+/// Read a timestamp for measurements.
 ///
-/// This function is a wrapper around [`llvmint`] to make it easier to test various
-/// implementations of reading a cycle counter. In this way, an experiment only has to
+/// This function is a wrapper around different ways to get a timestamp, fast
+/// In this way, an experiment only has to
 /// change this implementation rather than every instead of [`cpu::read_time_counter`]
-#[cfg(target_arch = "x86_64")]
+/// It is using [`rdtsc`] on `x86_64` and `x86`.
+#[cfg(any(target_arch = "x86_64", target_arch = "x86"))]
 #[must_use]
 pub fn read_time_counter() -> u64 {
     unsafe { core::arch::x86_64::_rdtsc() }
 }
+
+/// Read a timestamp for measurements.
+///
+/// This function is a wrapper around different ways to get a timestamp, fast
+/// In this way, an experiment only has to
+/// change this implementation rather than every instead of [`cpu::read_time_counter`]
+/// On unsupported architectures, it's falling back to normal system time, in millis.
+#[cfg(not(any(target_arch = "x86_64", target_arch = "x86")))]
+pub fn read_time_counter() -> u64 {
+    current_nanos()
+}