Changeset 60670 in vbox

Timestamp:

Apr 23, 2016 12:07:01 AM (8 years ago)

Author:

vboxsync

Message:

IEM: Made SIDT+SGDT store 0xff in high base byte when emulating a 286.

File:

• trunk/src/VBox/VMM/VMMAll/IEMAll.cpp (modified) (2 diffs)

trunk/src/VBox/VMM/VMMAll/IEMAll.cpp

@@ -7586 +7586 @@
 iemMemStoreDataXdtr(PIEMCPU pIemCpu, uint16_t cbLimit, RTGCPTR GCPtrBase, uint8_t iSegReg, RTGCPTR GCPtrMem, IEMMODE enmOpSize)
 {
+    /** @todo Looks like SIDT and SGDT performce two separate writes here,
+     *        first the limit, then base. Should the base write hit a segment
+     *        limit, the first write isn't rolled back. */
     uint8_t *pu8Src;
     VBOXSTRICTRC rcStrict = iemMemMap(pIemCpu,
@@ -7605 +7608 @@
         pu8Src[4] = RT_BYTE3(GCPtrBase);
         if (enmOpSize == IEMMODE_16BIT)
-            pu8Src[5] = 0; /* Note! the 286 stored 0xff here. */
+            pu8Src[5] = IEM_GET_TARGET_CPU(pIemCpu) <= IEMTARGETCPU_286 ? 0xff : 0x00;
         else
         {