Add atomic examples (#111)

* Add atomic examples

* Remove #[no_mangle]

examples/always_failure.rs

@@ -0,0 +1,11 @@
+#![no_std]
+#![no_main]
+
+use ckb_std::{default_alloc, entry};
+
+entry!(main);
+default_alloc!();
+
+fn main() -> i8 {
+    1
+}

examples/always_success.rs

@@ -0,0 +1,11 @@
+#![no_std]
+#![no_main]
+
+use ckb_std::{default_alloc, entry};
+
+entry!(main);
+default_alloc!();
+
+fn main() -> i8 {
+    0
+}

examples/atomic.rs

@@ -0,0 +1,91 @@
+#![no_main]
+#![no_std]
+
+// Copied from https://github.com/rust-lang/rust/blob/master/library/core/tests/atomic.rs.
+
+use ckb_std::{default_alloc, entry};
+use core::sync::atomic::Ordering::SeqCst;
+use core::sync::atomic::*;
+
+entry!(main);
+default_alloc!();
+
+fn bool_compare_exchange() {
+    let a = AtomicBool::new(false);
+    assert_eq!(a.compare_exchange(false, true, SeqCst, SeqCst), Ok(false));
+    assert_eq!(a.compare_exchange(false, true, SeqCst, SeqCst), Err(true));
+
+    a.store(false, SeqCst);
+    assert_eq!(a.compare_exchange(false, true, SeqCst, SeqCst), Ok(false));
+}
+
+fn bool_and() {
+    let a = AtomicBool::new(true);
+    assert_eq!(a.fetch_and(false, SeqCst), true);
+    assert_eq!(a.load(SeqCst), false);
+}
+
+fn bool_nand() {
+    let a = AtomicBool::new(false);
+    assert_eq!(a.fetch_nand(false, SeqCst), false);
+    assert_eq!(a.load(SeqCst), true);
+    assert_eq!(a.fetch_nand(false, SeqCst), true);
+    assert_eq!(a.load(SeqCst), true);
+    assert_eq!(a.fetch_nand(true, SeqCst), true);
+    assert_eq!(a.load(SeqCst), false);
+    assert_eq!(a.fetch_nand(true, SeqCst), false);
+    assert_eq!(a.load(SeqCst), true);
+}
+
+fn uint_and() {
+    let x = AtomicUsize::new(0xf731);
+    assert_eq!(x.fetch_and(0x137f, SeqCst), 0xf731);
+    assert_eq!(x.load(SeqCst), 0xf731 & 0x137f);
+}
+
+fn uint_nand() {
+    let x = AtomicUsize::new(0xf731);
+    assert_eq!(x.fetch_nand(0x137f, SeqCst), 0xf731);
+    assert_eq!(x.load(SeqCst), !(0xf731 & 0x137f));
+}
+
+fn uint_or() {
+    let x = AtomicUsize::new(0xf731);
+    assert_eq!(x.fetch_or(0x137f, SeqCst), 0xf731);
+    assert_eq!(x.load(SeqCst), 0xf731 | 0x137f);
+}
+
+fn uint_xor() {
+    let x = AtomicUsize::new(0xf731);
+    assert_eq!(x.fetch_xor(0x137f, SeqCst), 0xf731);
+    assert_eq!(x.load(SeqCst), 0xf731 ^ 0x137f);
+}
+
+fn uint_min() {
+    let x = AtomicUsize::new(0xf731);
+    assert_eq!(x.fetch_min(0x137f, SeqCst), 0xf731);
+    assert_eq!(x.load(SeqCst), 0x137f);
+    assert_eq!(x.fetch_min(0xf731, SeqCst), 0x137f);
+    assert_eq!(x.load(SeqCst), 0x137f);
+}
+
+fn uint_max() {
+    let x = AtomicUsize::new(0x137f);
+    assert_eq!(x.fetch_max(0xf731, SeqCst), 0x137f);
+    assert_eq!(x.load(SeqCst), 0xf731);
+    assert_eq!(x.fetch_max(0x137f, SeqCst), 0xf731);
+    assert_eq!(x.load(SeqCst), 0xf731);
+}
+
+fn main() -> i8 {
+    bool_compare_exchange();
+    bool_and();
+    bool_nand();
+    uint_and();
+    uint_nand();
+    uint_or();
+    uint_xor();
+    uint_min();
+    uint_max();
+    return 0;
+}

src/syscalls/native.rs

@@ -559,7 +559,8 @@ pub fn exec(index: usize, source: Source, place: usize, bounds: usize, argv: &[&
     // https://www.gnu.org/software/libc/manual/html_node/Program-Arguments.html
     let argc = argv.len();
     // On some platforms, CStr may be u8, adding as *const i8 is used to reduce such warnings
-    let argv_ptr: alloc::vec::Vec<*const i8> = argv.iter().map(|e| e.as_ptr() as *const i8).collect();
+    let argv_ptr: alloc::vec::Vec<*const i8> =
+        argv.iter().map(|e| e.as_ptr() as *const i8).collect();
     unsafe {
         syscall(
             index as u64,

test/Makefile

@@ -9,8 +9,10 @@ build:
 	cd ../contracts && RUSTFLAGS="-C target-feature=-a" cargo build --target riscv64imac-unknown-none-elf
 
 build-examples:
+	cd ../examples && RUSTFLAGS="-C target-feature=-a" cargo build --features build-with-clang --example always_failure --target riscv64imac-unknown-none-elf
+	cd ../examples && RUSTFLAGS="-C target-feature=-a" cargo build --features build-with-clang --example always_success --target riscv64imac-unknown-none-elf
+	cd ../examples && RUSTFLAGS="-C target-feature=-a" cargo build --features build-with-clang --example atomic --target riscv64imac-unknown-none-elf
 	cd ../examples && RUSTFLAGS="-C target-feature=-a" cargo build --features build-with-clang --example type_id --target riscv64imac-unknown-none-elf --features "type-id"
-	cd ../examples && RUSTFLAGS="-C target-feature=-a" cargo build --features build-with-clang --example main --target riscv64imac-unknown-none-elf
 
 clean:
 	rm -rf ../build

test/src/type_id.rs

@@ -9,7 +9,7 @@ const MAX_CYCLES: u64 = 1000_0000;
 fn build_bins() -> (Bytes, Bytes) {
     let always_success_bin = {
         let mut buf = Vec::new();
-        File::open("../target/riscv64imac-unknown-none-elf/debug/examples/main")
+        File::open("../target/riscv64imac-unknown-none-elf/debug/examples/always_success")
             .unwrap()
             .read_to_end(&mut buf)
             .expect("read code");