Translates from WebAssembly s-expressions to the WebAssembly binary encoding.
Clone as normal, but don't forget to update/init submodules as well:
$ git clone https://github.com/WebAssembly/sexpr-wasm-prototype $ git submodule update --init
This will fetch the v8 and testsuite repos, which are needed for some tests.
Building just sexpr-wasm:
$ make mkdir out cc -Wall -Werror -g -Wno-unused-function -Wno-return-type -c -o out/wasm.o -MMD -MP -MF out/wasm.d src/wasm.c cc -Wall -Werror -g -Wno-unused-function -Wno-return-type -c -o out/sexpr-wasm.o -MMD -MP -MF out/sexpr-wasm.d src/sexpr-wasm.c cc -Wall -Werror -g -Wno-unused-function -Wno-return-type -c -o out/wasm-parser.o -MMD -MP -MF out/wasm-parser.d src/wasm-parser.c cc -Wall -Werror -g -Wno-unused-function -Wno-return-type -c -o out/wasm-lexer.o -MMD -MP -MF out/wasm-lexer.d src/wasm-lexer.c cc -Wall -Werror -g -Wno-unused-function -Wno-return-type -c -o out/wasm-vector.o -MMD -MP -MF out/wasm-vector.d src/wasm-vector.c cc -Wall -Werror -g -Wno-unused-function -Wno-return-type -c -o out/wasm-check.o -MMD -MP -MF out/wasm-check.d src/wasm-check.c cc -Wall -Werror -g -Wno-unused-function -Wno-return-type -c -o out/wasm-writer.o -MMD -MP -MF out/wasm-writer.d src/wasm-writer.c cc -Wall -Werror -g -Wno-unused-function -Wno-return-type -c -o out/wasm-binary-writer.o -MMD -MP -MF out/wasm-binary-writer.d src/wasm-binary-writer.c cc -o out/sexpr-wasm out/wasm.o out/sexpr-wasm.o out/wasm-parser.o out/wasm-lexer.o out/wasm-vector.o out/wasm-check.o out/wasm-writer.o out/wasm-binary-writer.o
If you make changes to src/wasm-parser.y, you'll need to install bison as well. On Debian-based systems:
$ sudo apt-get install bison ... $ touch src/wasm-parser.y $ make bison -o src/wasm-parser.c --defines=src/wasm-parser.h src/wasm-parser.y ...
If you make changes to src/wasm-lexer.l, you'll need to install flex as well. On Debian-based systems:
$ sudo apt-get install flex ... $ touch src/wasm-lexer.l $ make flex -o src/wasm-lexer.c src/wasm-lexer.l ...
d8 can load and run the generated binary-encoded files. Some of the tests rely on this executable. To build it:
$ scripts/build-d8.sh ...
When it is finished, there will be a d8 executable in the
third_party/v8/v8/out/Release directory.
You can also download a prebuilt version (the same one used to test on Travis) by running the download-d8.sh script:
$ scripts/download-d8.sh ...
This downloads the d8 executable into the out directory. The test runner
will look here if there is no d8 executable in the
third_party/v8/v8/out/Release directory.
First write some WebAssembly s-expressions:
$ cat > test.wast << HERE
(module
(export "test" 0)
(func (result i32)
(i32.add (i32.const 1) (i32.const 2))))
HERE
Then run sexpr-wasm to build a binary-encoded file:
$ out/sexpr-wasm test.wast -o test.wasm
This can be loaded into d8 using JavaScript like this:
$ third_party/v8/v8/out/Release/d8
V8 version 4.7.0 (candidate)
d8> buffer = readbuffer('test.wasm');
[object ArrayBuffer]
d8> module = _WASMEXP_.instantiateModule(buffer, {});
{memory: [object ArrayBuffer], test: function test() { [native code] }}
d8> module.test()
3
If you just want to run a quick test, you can use the run-d8.py script instead:
$ test/run-d8.py test.wast test() = 3
To run spec-style tests (with assert_eq, invoke, etc.) use the --spec flag:
$ cat > test2.wast << HERE
(module
(export "neg" 0)
(func (param i32) (result i32)
(i32.sub (i32.const 0) (get_local 0))))
(assert_eq (invoke "neg" (i32.const 100)) (i32.const -100))
HERE
$ test/run-d8.py --spec test2.wast
instantiating module
$assert_eq_0 OK
1/1 tests passed.
To run tests:
$ make test [+420|-0|%100] (1.95s)
In this case, there were 420 passed tests and no failed tests, which took 1.95 seconds to run.
You can also run the Python test runner script directly:
$ test/run-tests.py [+420|-0|%100] (1.99s) $ test/run-tests.py -v . spec/address.txt (skipped) . spec/fac.txt (skipped) . spec/runaway-recursion.txt (skipped) + d8/assertreturn-complex-module.txt (0.044s) + d8/assertreturn-invoke-ordering.txt (0.063s) + d8/assertreturn-failed.txt (0.068s) + d8/assertreturn-types.txt (0.077s) + d8/basic.txt (0.060s) + d8/assertreturn.txt (0.089s) + d8/assertreturnnan.txt (0.069s) ...
To run a subset of the tests, use a glob-like syntax:
$ test/run-tests.py const -v + dump/const.txt (0.002s) + parse/expr/bad-const-f32-trailing.txt (0.002s) + parse/assert/bad-assertreturn-non-const.txt (0.004s) + parse/expr/bad-const-i32-garbage.txt (0.003s) + parse/expr/bad-const-i32-trailing.txt (0.003s) + parse/expr/bad-const-i32-overflow.txt (0.004s) + parse/expr/bad-const-i32-underflow.txt (0.002s) + parse/expr/bad-const-i32-just-negative-sign.txt (0.006s) + parse/expr/bad-const-i64-overflow.txt (0.002s) + parse/expr/const.txt (0.002s) [+10|-0|%100] (0.01s) $ test/run-tests.py expr*const*i32 -v + parse/expr/bad-const-i32-garbage.txt (0.003s) + parse/expr/bad-const-i32-underflow.txt (0.003s) + parse/expr/bad-const-i32-overflow.txt (0.005s) + parse/expr/bad-const-i32-just-negative-sign.txt (0.005s) + parse/expr/bad-const-i32-trailing.txt (0.005s) [+5|-0|%100] (0.01s)
When tests are broken, they will give you the expected stdout/stderr as a diff:
$ <introduce bug in wasm-binary-writer.c> $ test/run-tests.py d8/store - d8/store.txt STDOUT MISMATCH: --- expected +++ actual @@ -1,9 +1,9 @@ i32_store8() = -16909061 -i32_store16() = -859059511 -i32_store() = -123456 +i32_store16() = -16909061 +i32_store() = -16909120 i64_store8() = -16909061 i64_store16() = -859059511 -i64_store32() = -123456 -i64_store() = 1 -f32_store() = 1069547520 -f64_store() = -1064352256 +i64_store32() = -859059511 +i64_store() = 0 +f32_store() = -859059699 +f64_store() = 61166 **** FAILED ****************************************************************** - d8/store.txt [+0|-1|%100] (0.03s)
Tests must be placed in the test/ directory, and must have the extension .txt. The directory structure is mostly for convenience, so for example you can type test/run-tests.py d8 to run all the tests that execute in d8. There's otherwise no logic attached to a test being in a given directory.
That being said, try to make the test names self explanatory, and try to test only one thing. Also make sure that tests that are expected to fail start with bad-.
The test format is straightforward:
;;; KEY1: VALUE1A VALUE1B... ;;; KEY2: VALUE2A VALUE2B... (input (to) (the executable)) (;; STDOUT ;;; expected stdout ;;; STDOUT ;;) (;; STDERR ;;; expected stderr ;;; STDERR ;;)
The test runner will copy the input to a temporary file and pass it as an argument to the executable (which by default is out/sexpr-wasm).
The currently supported list of keys:
- EXE: the executable to run, defaults to out/sexpr-wasm
- STDIN_FILE: the file to use for STDIN instead of the contents of this file.
- FLAGS: additional flags to pass to the executable
- ERROR: the expected return value from the executable, defaults to 0
- SLOW: if defined, this test's timeout is doubled.
- SKIP: if defined, this test is not run. You can use the value as a comment.
When you first write a test, it's easiest if you omit the expected stdout and stderr. You can have the test harness fill it in for you automatically. First let's write our test:
$ cat > test/my-awesome-test.txt << HERE
;;; EXE: test/run-d8.py
;;; FLAGS: --spec
(module
(export "add2" 0)
(func (param i32) (result i32)
(i32.add (get_local 0) (i32.const 2))))
(assert_return (invoke "add2" (i32.const 4)) (i32.const 6))
(assert_return (invoke "add2" (i32.const -2)) (i32.const 0))
HERE
If we run it, it will fail:
- my-awesome-test.txt STDOUT MISMATCH: --- expected +++ actual @@ -0,0 +1 @@ +2/2 tests passed. **** FAILED ****************************************************************** - my-awesome-test.txt [+0|-1|%100] (0.03s)
We can rebase it automatically with the -r flag. Running the test again shows that the expected stdout has been added:
$ test/run-tests.py my-awesome-test -r [+1|-0|%100] (0.03s) $ test/run-tests.py my-awesome-test [+1|-0|%100] (0.03s) $ tail -n 3 test/my-awesome-test.txt (;; STDOUT ;;; 2/2 tests passed. ;;; STDOUT ;;)
To build with the LLVM sanitizers, append the sanitizer name to sexpr-wasm:
$ make out/sexpr-wasm-asan clang -fsanitize=address -Wall -Werror -g -Wno-unused-function -Wno-return-type -c -o out/wasm.asan.o -MMD -MP -MF out/wasm.asan.d src/wasm.c ... $ make out/sexpr-wasm-msan clang -fsanitize=memory -Wall -Werror -g -Wno-unused-function -Wno-return-type -c -o out/wasm.msan.o -MMD -MP -MF out/wasm.msan.d src/wasm.c ... $ make out/sexpr-wasm-lsan clang -fsanitize=leak -Wall -Werror -g -Wno-unused-function -Wno-return-type -c -o out/wasm.lsan.o -MMD -MP -MF out/wasm.lsan.d src/wasm.c ...
There are configurations for the Address Sanitizer (ASAN), Memory Sanitizer (MSAN) and Leak Sanitizer (LSAN). You can read about the behaviors of the sanitizers in the link above, but essentially the Address Sanitizer finds invalid memory accesses (use after free, access out-of-bounds, etc.), Memory Sanitizer finds uses of uninitialized memory, and the Leak Sanitizer finds memory leaks.
Typically, you'll just want to run all the tests for a given sanitizer:
$ make test-asan [+420|-0|%100] (12.59s) $ make test-msan [+420|-0|%100] (4.69s) $ make test-lsan [+420|-0|%100] (5.41s)
The Travis bots run all of these tests. Before you land a change, you should
run them too. One easy way is to use the test-everything target:
$ make test-everything [+420|-0|%100] (1.71s) [+420|-0|%100] (12.20s) [+420|-0|%100] (4.71s) [+420|-0|%100] (5.52s)