Allow PNaCl NMF to set translator optimization options for experimentation.

ppapi/native_client/src/trusted/plugin/pnacl_options.cc

+// Copyright (c) 2013 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include "native_client/src/trusted/plugin/pnacl_options.h"
+
+#include <iterator>
+#include <vector>
+
+#include "native_client/src/include/nacl_string.h"
+
+namespace plugin {
+
+// Default to -O0 for now.
+PnaclOptions::PnaclOptions() : translate_(false), opt_level_(0) { }
+
+PnaclOptions::~PnaclOptions() {
+}
+
+nacl::string PnaclOptions::GetCacheKey() {
+  // TODO(jvoung): We need to read the PNaCl translator's manifest
+  // to grab the NaCl / PNaCl ABI version too.
+  nacl::stringstream ss;
+  // Cast opt_level_ as int so that it doesn't think it's a char.
+  ss << "-O:" << static_cast<int>(opt_level_)
+     << ";flags:" << experimental_flags_
+     <<  ";bitcode_hash:" << bitcode_hash_;
+  return ss.str();
+}
+
+void PnaclOptions::set_opt_level(int8_t l) {
+  if (l < 0) {
+    opt_level_ = 0;
+    return;
+  }
+  if (l > 3) {
+    opt_level_ = 3;
+    return;
+  }
+  opt_level_ = l;
+}
+
+std::vector<char> PnaclOptions::GetOptCommandline() {
+  std::vector<char> result;
+  std::vector<nacl::string> tokens;
+
+  // Split the experimental_flags_ + the -On along whitespace.
+  // Mostly a copy of "base/string_util.h", but avoid importing
+  // base into the PPAPI plugin for now.
+  nacl::string delim(" ");
+  nacl::string str = experimental_flags_;
+
+  if (opt_level_ != -1) {
+    nacl::stringstream ss;
+    // Cast as int so that it doesn't think it's a char.
+    ss << " -O" << static_cast<int>(opt_level_);
+    str += ss.str();
+  }
+
+  size_t start = str.find_first_not_of(delim);
+  while (start != nacl::string::npos) {
+    size_t end = str.find_first_of(delim, start + 1);
+    if (end == nacl::string::npos) {
+      tokens.push_back(str.substr(start));
+      break;
+    } else {
+      tokens.push_back(str.substr(start, end - start));
+      start = str.find_first_not_of(delim, end + 1);
+    }
+  }
+
+  for (size_t i = 0; i < tokens.size(); ++i) {
+    nacl::string t = tokens[i];
+    result.reserve(result.size() + t.size());
+    std::copy(t.begin(), t.end(), std::back_inserter(result));
+    result.push_back('\x00');
+  }
+
+  return result;
+}
+
+}  // namespace plugin