Library sandboxing changes

- Windows/msvc support for runtime, codegen and builtins as well as support for a wider list of platforms/architectures/compilers including Android (arm architectures), Windows 32-bit etc.
- Support for growable indirect function call tables
- Support for library sandboxing apis --- wasm function type index lookup (so host can add new callbacks), make heaps aligned to 4gb for compatiblity with the RLBox sandboxing framework
- Allow multiple sandbox instances of the same library by moving global vars into a context structure that is passed to every function
- Migrated from emscripten to use of wasi-clang
- Upstream libc-wasi does not support windows, so I have written a minimal cross platform wasi support which includes just basic wasi function (just enough to get simple IO libraries running. Nothing complicated like networking or filesystem is supported)
- Removed use of per function call signal handler, setjmp/longjmp as this slows transitions
- Removed name mangling to simplify function lookup
- Remove stack depth counting as this adds unnecessary overhead
- A debugging aid built directly into wasm2c generated code that is similar to valgrind like shadow memory (significantly eases debugging of wasm)
- A wasm2c runner that can run full applications (code that has a main), when they are compiled via wasm2c to C and then to a shared library (.so/.dll)

.gitignore

@@ -1,9 +1,10 @@
 /bin
-/build
+/build*
 /out
 /fuzz-out
 /emscripten
 *.pyc
+*.o
 .idea/
 .vscode/
 /cmake-build-debug/

CMakeLists.txt

@@ -351,11 +351,9 @@ set(WABT_LIBRARY_SRC
 
 add_library(wabt STATIC ${WABT_LIBRARY_SRC})
 
-IF (NOT WIN32)
-  add_library(wasm-rt-impl STATIC wasm2c/wasm-rt-impl.c wasm2c/wasm-rt-impl.h)
-  install(TARGETS wasm-rt-impl DESTINATION ${CMAKE_INSTALL_LIBDIR})
-  install(FILES wasm2c/wasm-rt.h wasm2c/wasm-rt-impl.h DESTINATION ${CMAKE_INSTALL_INCLUDEDIR})
-endif ()
+add_library(wasm-rt-impl STATIC SHARED wasm2c/wasm-rt-impl.c wasm2c/wasm-rt-os-unix.c wasm2c/wasm-rt-os-win.c wasm2c/wasm-rt-wasi.c)
+install(TARGETS wasm-rt-impl DESTINATION ${CMAKE_INSTALL_LIBDIR})
+install(FILES wasm2c/wasm-rt.h DESTINATION ${CMAKE_INSTALL_INCLUDEDIR})
 
 if (BUILD_FUZZ_TOOLS)
   set(FUZZ_FLAGS "-fsanitize=fuzzer,address")
@@ -472,6 +470,19 @@ if (BUILD_TOOLS)
     INSTALL
   )
 
+if (NOT WIN32)
+  set(LDL_LIB "-ldl")
+else()
+  set(LDL_LIB "")
+endif()
+
+  wabt_executable(
+    NAME wasm2c-runner
+    SOURCES wasm2c/wasm-rt-runner.c
+    LIBS ${LDL_LIB}
+    INSTALL
+  )
+
   # wasm-opcodecnt
   wabt_executable(
     NAME wasm-opcodecnt