Implement SysInfo::CPUArchitecture() on Windows.

base/sys_info_posix.cc

Index: base/sys_info_posix.cc
===================================================================
--- base/sys_info_posix.cc	(revision 156435)
+++ base/sys_info_posix.cc	(working copy)
@@ -79,7 +79,13 @@
     NOTREACHED();
     return "";
   }
-  return std::string(info.machine);
+  std::string arch(info.machine);
+  if (arch == "i386" || arch == "i486" || arch == "i586" || arch == "i686") {
+    arch = "x86";
+  } else if (arch == "amd64") {
+    arch = "x86_64";

[Mark Mentovai, 2012/09/13 12:40:19]

For Mac and Linux x86_*, this returns the kernel’s bitness, which may not be the
same thing as the underlying hardware’s actual capability (32-bit kernel running
on 64-bit CPU) and may not be the same thing as the running Chrome’s bitness
(32-bit Chrome running on 64-bit kernel, or for that matter on the Mac, 64-bit
Chrome running on 32-bit kernel—except there currently is no 64-bit Mac Chrome).

Is all of this OK? Is it comparable to the behavior on Windows? The comment in
the header doesn’t explain which architecture of (CPU, kernel, app) this is
expected to return.

[Lei Zhang, 2012/09/21 21:10:21]

Right, I think CPUArchitecture() should be renamed to OSArch(). The behavior on
Windows matches the behavior on Linux. I've added additional comments in the
header.

+  }
+  return arch;
 }
 
 // static