Don't create a Bigint object first for every integer while parsing the sources, instead first check…

vm/os_macos.cc

 // Copyright (c) 2012, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 #include "vm/os.h"
 
 #include <errno.h>
 #include <limits.h>
 #include <mach/mach.h>
 #include <mach/clock.h>
@@ skipping 118 matching lines @@
 
 int OS::VSNPrint(char* str, size_t size, const char* format, va_list args) {
   int retval = vsnprintf(str, size, format, args);
   if (retval < 0) {
     FATAL1("Fatal error in OS::VSNPrint with format '%s'", format);
   }
   return retval;
 }
 
 
+bool OS::StringToInteger(const char* str, int64_t* value) {
+  ASSERT(str != NULL && strlen(str) > 0 && value != NULL);
+  bool negative_value = false;
+  int32_t base = 10;
+  if (str[0] == '-') {
+    negative_value = true;
+    str += 1;
+  }
+  if ((str[0] == '0') && (str[1] == 'x' || str[1] == 'X') && (str[2] != '\0')) {
+    base = 16;
+  }
+  errno = 0;
+  *value = strtoll(str, NULL, base);
+  if (errno == 0) {
+    if (negative_value) {
+      *value = -(*value);
+    }
+    return true;
+  }
+  return false;
+}
+
+
 void OS::PrintErr(const char* format, ...) {
   va_list args;
   va_start(args, format);
   VFPrint(stderr, format, args);
   va_end(args);
 }
 
 
 void OS::InitOnce() {
   // TODO(5411554): For now we check that initonce is called only once,
@@ skipping 12 matching lines @@
 void OS::Abort() {
   abort();
 }
 
 
 void OS::Exit(int code) {
   exit(code);
 }
 
 }  // namespace dart