win: support x64 reading x86 (wow64)

util/win/process_structs.h

Index: util/win/process_structs.h
diff --git a/util/win/process_structs.h b/util/win/process_structs.h
index 7f4e4f59e77e7f3561f37aa091f7ab365f89194e..5b8985077fe53d6cfde0887e1619be830fc236b4 100644
--- a/util/win/process_structs.h
+++ b/util/win/process_structs.h
@@ -283,7 +283,11 @@ struct PEB {
 
 template <class Traits>
 struct NT_TIB {
-  typename Traits::Pointer ExceptionList;
+  union {
+    typename Traits::Pointer ExceptionList;
+    // See https://msdn.microsoft.com/en-us/library/dn424783.aspx.

[Mark Mentovai, 2015/09/18 15:44:07]

But the rest of NT_TIB isn’t right for WoW64 either, is it? Maybe this:

  union {
    struct {
      ExceptionList;
      StackBase;
    };
    Wow64Teb;
  };

[scottmg, 2015/09/18 19:45:26]

I'm not sure if it is. I think it probably has the associated 64 bit data? But
we don't care about that, so seems reasonable.

[Mark Mentovai, 2015/09/18 22:10:50]

scottmg wrote:
Well, if each thread has its own distinct 64-bit stack, then what you had is
maybe more correct. Your call. Like you said, we don’t actually use anything
else in the WoW64 case, so there’s no practical difference.

+    typename Traits::Pointer Wow64Teb;
+  };
   typename Traits::Pointer StackBase;
   typename Traits::Pointer StackLimit;
   typename Traits::Pointer SubSystemTib;
@@ -417,7 +421,7 @@ struct SYSTEM_PROCESS_INFORMATION {
 template <class Traits>
 struct THREAD_BASIC_INFORMATION {
   union {
-    NTSTATUS ExitStatus;
+    LONG ExitStatus;
     typename Traits::Pad padding_for_x64_0;
   };
   typename Traits::Pointer TebBaseAddress;
@@ -427,6 +431,12 @@ struct THREAD_BASIC_INFORMATION {
   LONG BasePriority;
 };
 
+template <class Traits>
+struct EXCEPTION_POINTERS {
+  typename Traits::Pointer ExceptionRecord;
+  typename Traits::Pointer ContextRecord;
+};
+
 #pragma pack(pop)
 
 //! \}