[wasm] Adding feature to JIT a wasm function at runtime and hook up the compiled code into the indi…

src/runtime/runtime-internal.cc

Index: src/runtime/runtime-internal.cc
diff --git a/src/runtime/runtime-internal.cc b/src/runtime/runtime-internal.cc
index 6ffb667f2df52d1324f574f138ef4a3f4eab9123..5bf4c02f1aaf18225c4f9c58574b14f41a87f72a 100644
--- a/src/runtime/runtime-internal.cc
+++ b/src/runtime/runtime-internal.cc
@@ -7,6 +7,7 @@
 #include "src/arguments.h"
 #include "src/ast/prettyprinter.h"
 #include "src/bootstrapper.h"
+#include "src/compiler/wasm-compiler.h"
 #include "src/conversions.h"
 #include "src/debug/debug.h"
 #include "src/frames-inl.h"
@@ -152,6 +153,56 @@ RUNTIME_FUNCTION(Runtime_ThrowWasmError) {
   return isolate->Throw(*error_obj);
 }
 
+RUNTIME_FUNCTION(Runtime_JITSingleFunction) {
+  HandleScope scope(isolate);
+  DCHECK_LE(7, args.length());

[Mircea Trofin, 2016/07/12 02:49:12]

same comment as before about numbers - if possible, define and use constants.
Helps maintainability.

[ritesht, 2016/07/13 23:58:45]

Done.

+  CONVERT_SMI_ARG_CHECKED(base, 0);
+  CONVERT_SMI_ARG_CHECKED(length, 1);
+  CONVERT_SMI_ARG_CHECKED(index, 2);
+  CONVERT_INTPTR_ARG_CHECKED(start, 3);
+  CONVERT_ARG_HANDLE_CHECKED(FixedArray, function_table, 4);
+  CONVERT_SMI_ARG_CHECKED(sig_index, 5);
+  CONVERT_UINT32_ARG_CHECKED(return_count, 6);
+
+  wasm::WasmModule module(reinterpret_cast<byte*>(start));
+  wasm::ErrorThrower thrower(isolate, "JITSingleFunction");
+  wasm::ModuleEnv module_env;
+  module_env.module = &module;
+  module_env.instance = nullptr;
+  module_env.origin = wasm::kWasmOrigin;
+
+  uint32_t signature_size = args.length() - 7;
+  wasm::LocalType* sig_types = new wasm::LocalType[signature_size];
+
+  for (uint32_t i = 0; i < signature_size; ++i) {
+    CONVERT_SMI_ARG_CHECKED(sig_type, i + 7);
+    sig_types[i] = static_cast<wasm::LocalType>(sig_type);
+  }
+  wasm::FunctionSig sig(return_count, signature_size - return_count, sig_types);
+
+  wasm::WasmFunction func;
+  func.sig = &sig;
+  func.func_index = index;
+  func.sig_index = sig_index;
+  func.name_offset = 0;
+  func.name_length = 0;
+  func.code_start_offset = base;
+  func.code_end_offset = base + length;
+
+  Handle<Code> code = compiler::WasmCompilationUnit::CompileWasmFunction(
+      &thrower, isolate, &module_env, &func);
+
+  delete[] sig_types;
+  if (thrower.error()) {
+    return isolate->heap()->undefined_value();
+  }
+
+  function_table->set(index, Smi::FromInt(sig_index));
+  function_table->set(index + function_table->length() / 2, *code);

[Mircea Trofin, 2016/07/12 02:49:13]

do you want to check that index < function_table->length() / 2?

[ritesht, 2016/07/13 23:58:45]

Done.

+
+  return isolate->heap()->undefined_value();
+}
+
 RUNTIME_FUNCTION(Runtime_UnwindAndFindExceptionHandler) {
   SealHandleScope shs(isolate);
   DCHECK(args.length() == 0);