Translates WebAssembly modules to C. Inspired by wabt's wasm2c.

• Implements the WebAssembly Core Specification 1.0
• Passes 99.9% of the WebAssembly core semantics test suite
• Written in C89 and generates C89
• Support for older operating systems and architectures
• Support for big-endian systems
• Streaming compilation, low memory usage
• Parallel compilation into multiple files
• WASI implementation which is able to run clang.wasm

• Coremark 1.0: ~7% slower than native

make

To enables certain features, list them in the FEATURES variable passed to make, e.g. make FEATURES="threads":

• Parallel compilation requires pthreads on the host system. Add threads to FEATURES.
• If the host system has support for getopt, add getopt to FEATURES.
• Generating debug information requires libdwarf on the host system. Add debugging to FEATURES.

Compile module.wasm to module.c:

./w2c2 -o module.c module.wasm

Compile module.wasm using 12 concurrent jobs into multiple files with 100 functions each:

./w2c2 -o module_directory -j 12 -f 100 module.wasm

Coremark:

cd examples/coremark
./coremark

Requires Python 3 and wabt (for wast2json).

cd tests
make gen
make run-tests

• args_get
• args_sizes_get
• clock_res_get
• clock_time_get
• environ_get
• environ_sizes_get
• fd_advise
• fd_allocate
• fd_close
• fd_datasync
• fd_fdstat_get
• fd_fdstat_set_flags
• fd_fdstat_set_rights
• fd_filestat_get
• fd_filestat_set_size
• fd_filestat_set_times
• fd_pread
• fd_prestat_get
• fd_prestat_dir_name
• fd_pwrite
• fd_read
• fd_readdir
• fd_renumber
• fd_seek
• fd_sync
• fd_tell
• fd_write
• path_create_directory
• path_filestat_get
• path_filestat_set_times
• path_link
• path_open
• path_readlink
• path_remove_directory
• path_rename
• path_symlink
• path_unlink_file
• poll_oneoff
• proc_exit
• random_get
• sched_yield
• sock_recv
• sock_send
• sock_shutdown

To build a debug release, pass BUILD=debug to make.

To enable sanitizers, list them in the SANITIZERS variable passed to make, e.g. make BUILD=debug SANITIZERS="base clang address thread".

• base enables the Undefined Behavior Sanitizer
• clang enables Clang-specific sanitizers
• thread enables the Thread Sanitizer
• address enables the Address Sanitizer