Initial Subzero WASM prototype.

src/IceCompiler.cpp

Index: src/IceCompiler.cpp
diff --git a/src/IceCompiler.cpp b/src/IceCompiler.cpp
index bd5e8343a554bf1ada85fd1da831f64ce6007770..26eb5a1a7e8ef518249fb70df3f684d52b9e4339 100644
--- a/src/IceCompiler.cpp
+++ b/src/IceCompiler.cpp
@@ -27,6 +27,10 @@
 #include "IceELFObjectWriter.h"
 #include "PNaClTranslator.h"
 
+#ifdef SUBZERO_WASM
+#include "WasmTranslator.h"
+#endif

[JF, 2016/03/28 18:17:13]

Why not put the #if in the other header?

[Eric Holk, 2016/03/29 19:54:08]

Done.

+
 #ifdef __clang__
 #pragma clang diagnostic push
 #pragma clang diagnostic ignored "-Wunused-parameter"
@@ -55,6 +59,11 @@ bool llvmIRInput(const IceString &Filename) {
          std::regex_match(Filename, std::regex(".*\\.ll"));
 }
 
+bool wasmInput(const IceString &Filename) {
+  return BuildDefs::llvmIrAsInput() &&
+         std::regex_match(Filename, std::regex(".*\\.wasm"));

[JF, 2016/03/28 18:17:13]

Eek, I wouldn't use regex for this. It's a huge hammer. StringRef has
endswith().

[Eric Holk, 2016/03/29 19:54:08]

I just cargo-culted from the previous llvmIRInput function, although I agree
it's a bigger hammer than we need.

+}
+
 } // end of anonymous namespace
 
 void Compiler::run(const Ice::ClFlags &Flags, GlobalContext &Ctx,
@@ -78,13 +87,28 @@ void Compiler::run(const Ice::ClFlags &Flags, GlobalContext &Ctx,
 
   std::unique_ptr<Translator> Translator;
   const IceString &IRFilename = Flags.getIRFilename();
-  const bool BuildOnRead = Flags.getBuildOnRead() && !llvmIRInput(IRFilename);
+  const bool BuildOnRead = Flags.getBuildOnRead() && !llvmIRInput(IRFilename) &&
+                           !wasmInput(IRFilename);
+  const bool WasmBuildOnRead = Flags.getBuildOnRead() && wasmInput(IRFilename);
   if (BuildOnRead) {
     std::unique_ptr<PNaClTranslator> PTranslator(new PNaClTranslator(&Ctx));
     std::unique_ptr<llvm::StreamingMemoryObject> MemObj(
         new llvm::StreamingMemoryObjectImpl(InputStream.release()));
     PTranslator->translate(IRFilename, std::move(MemObj));
     Translator.reset(PTranslator.release());
+  } else if (WasmBuildOnRead) {
+#ifdef SUBZERO_WASM

[Jim Stichnoth, 2016/03/29 17:49:57]

We try to minimize the use of #ifdef code.  Where possible, the code is
conditional on some Ice::BuildDefs constexpr function so that mistakes are
caught by the compiler in early development.

Would that be possible here?

[Eric Holk, 2016/03/29 22:58:07]

My latest update should have basically no #ifdef code anymore.

+    std::unique_ptr<WasmTranslator> WTranslator(new WasmTranslator(&Ctx));
+
+    WTranslator->translate(IRFilename, std::move(InputStream));
+
+    Translator.reset(WTranslator.release());
+#else
+      Ctx.getStrError()
+          << "WASM support not enabled\n";
+      Ctx.getErrorStatus()->assign(EC_Args);
+      return;
+#endif

[JF, 2016/03/28 18:17:13]

Would be nice if this switch were only visible from the WasmTranslator.h file:
WasmTranslator could just be a stub class which emits this error.

[Eric Holk, 2016/03/29 19:54:08]

Done.

   } else if (BuildDefs::llvmIr()) {
     if (BuildDefs::browser()) {
       Ctx.getStrError()