Merge pull request #53 from arximboldi/enable-wasm

Add option to enable WebAssembly in LLVM

emsdk

@@ -55,6 +55,9 @@ GIT_CLONE_SHALLOW = False
 # If true, LLVM backend is built with tests enabled, and Binaryen is built with Visual Studio static analyzer enabled.
 BUILD_FOR_TESTING = False
 
+# If true, we will try to build WebAssembly support
+ENABLE_WASM = False
+
 # If 'auto', assertions are decided by the build type (Release&MinSizeRel=disabled, Debug&RelWithDebInfo=enabled)
 # Other valid values are 'ON' and 'OFF'
 ENABLE_LLVM_ASSERTIONS = 'auto'
@@ -742,6 +745,8 @@ def build_fastcomp_tool(tool):
   enable_assertions = ENABLE_LLVM_ASSERTIONS.lower() == 'on' or (ENABLE_LLVM_ASSERTIONS == 'auto' and build_type.lower() != 'release' and build_type.lower() != 'minsizerel')
 
   args = ['-DLLVM_TARGETS_TO_BUILD=X86;JSBackend', '-DLLVM_INCLUDE_EXAMPLES=OFF', '-DCLANG_INCLUDE_EXAMPLES=OFF', '-DLLVM_INCLUDE_TESTS=' + tests_arg, '-DCLANG_INCLUDE_TESTS=' + tests_arg, '-DLLVM_ENABLE_ASSERTIONS=' + ('ON' if enable_assertions else 'OFF')]
+  if ENABLE_WASM:
+    args += ['-DLLVM_EXPERIMENTAL_TARGETS_TO_BUILD=WebAssembly']
   success = cmake_configure(cmake_generator, build_root, fastcomp_src_root, build_type, args)
   if not success: return False
 
@@ -1875,6 +1880,9 @@ def main():
                                   passed to the emsdk activate command to
                                   activate the desired version.
 
+                   --enable-wasm: Enable WebAssembly support in the
+                                  installed components.
+
    emsdk uninstall <tool/sdk>   - Removes the given tool or SDK from disk.''')
 
     if WINDOWS:
@@ -2118,6 +2126,10 @@ def main():
       elif sys.argv[i] == '--disable-assertions':
         ENABLE_LLVM_ASSERTIONS = 'OFF'
         sys.argv[i] = ''
+      elif sys.argv[i] == '--enable-wasm':
+        global ENABLE_WASM
+        ENABLE_WASM = True
+        sys.argv[i] = ''
     sys.argv = [x for x in sys.argv if not len(x) == 0]
     if len(sys.argv) <= 2:
       print("Missing parameter. Type 'emsdk install <tool name>' to install a tool or an SDK. Type 'emsdk list' to obtain a list of available tools. Type 'emsdk install latest' to automatically install the newest version of the SDK.")