Initial Subzero WASM prototype.

src/WasmTranslator.h

Index: src/WasmTranslator.h
diff --git a/src/WasmTranslator.h b/src/WasmTranslator.h
new file mode 100644
index 0000000000000000000000000000000000000000..96af8068272373a2bb6105c3931857a9e4896469
--- /dev/null
+++ b/src/WasmTranslator.h
@@ -0,0 +1,58 @@
+//===- subzero/src/WasmTranslator.h - WASM to Subzero Translation ---------===//
+//
+//                        The Subzero Code Generator
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//

[Jim Stichnoth, 2016/04/01 01:46:45]

The license boilerplate usually also includes a blurb at the end about the
high-level purpose of the file.

[Eric Holk, 2016/04/01 19:15:03]

Done.

+
+#ifndef SUBZERO_SRC_WASMTRANSLATOR_H
+#define SUBZERO_SRC_WASMTRANSLATOR_H
+
+#include "IceGlobalContext.h"
+#include "IceTranslator.h"
+
+namespace v8 {
+namespace internal {
+class Zone;
+namespace wasm {
+class FunctionEnv;
+} // end of namespace wasm
+} // end of namespace internal
+} // end of namespace v8
+
+namespace Ice {
+
+class WasmTranslator : public Translator {
+  WasmTranslator() = delete;
+  WasmTranslator(const WasmTranslator &) = delete;
+  WasmTranslator &operator=(const WasmTranslator &) = delete;
+
+  template <typename F = std::function<void(Ostream &)>> void log(F Fn) {
+    if (BuildDefs::dump() && (Ctx->getFlags().getVerbose() & IceV_Wasm)) {
+      OstreamLocker L(Ctx);

[Jim Stichnoth, 2016/04/01 01:46:45]

The "new" Subzero style is to name this RAII variable "_" instead of "L", if
practical.

[Eric Holk, 2016/04/01 19:15:02]

Done.

+      Fn(Ctx->getStrDump());
+      Ctx->getStrDump().flush();

[Jim Stichnoth, 2016/04/01 01:46:45]

Just curious if this flush() is necessary and if we should be doing that in
strategic places elsewhere in the code base?  I had been under the impression
that "\n" would flush, but I could be wrong.

[Eric Holk, 2016/04/01 19:15:02]

It's normally not necessary. Early on I had inserted flushes in a few key places
(basically, where I thought the translator might crash before it got to a \n).
When I factored all the logging code into a function/macro, I decided to
conservatively flush everywhere. This code should only be present in
dump-enabled builds, so I don't think it hurts to leave it in but I'm happy to
remove it if you'd prefer.

+    }
+  }
+
+public:
+  explicit WasmTranslator(GlobalContext *Ctx);
+  ~WasmTranslator() override;
+
+  void translate(const std::string &IRFilename,
+                 std::unique_ptr<llvm::DataStreamer> InputStream);
+
+  std::unique_ptr<Cfg> translateFunction(v8::internal::Zone *zone,

[Jim Stichnoth, 2016/04/01 01:46:45]

Capitalize variable names per LLVM convention.

[Eric Holk, 2016/04/01 19:15:03]

Done.

+                                         v8::internal::wasm::FunctionEnv *env,
+                                         const uint8_t *base,

[Jim Stichnoth, 2016/04/01 01:46:45]

Can you document these arguments, especially base/start/end?

[Eric Holk, 2016/04/01 19:15:03]

Done.

With the latest v8 changes (coming in my next CL), base, start and end have been
combined into a single argument.

+                                         const uint8_t *start,
+                                         const uint8_t *end);
+
+private:
+  uint8_t *Buffer;
+  SizeT BufferSize;
+};
+}
+#endif // SUBZERO_SRC_WASMTRANSLATOR_H