Changeset 62411 in vbox

Timestamp:

Jul 21, 2016 8:48:14 PM (9 years ago)

Author:

vboxsync

svn:sync-xref-src-repo-rev:

108961

Message:

iemAImpl_mul_u64: Implemented flag behavior to match that of Intel Skylake 6700K.

File:

• trunk/src/VBox/VMM/VMMAll/IEMAllAImplC.cpp (modified) (1 diff)

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

@@ -1141 +1141 @@
     *pu64RAX = Result.s.Lo;
     *pu64RDX = Result.s.Hi;
-    /** @todo research the undefined MUL flags. */
+
+    /* MUL EFLAGS according to Skylake (similar to IMUL). */
+    *pfEFlags &= ~(X86_EFL_SF | X86_EFL_CF | X86_EFL_OF | X86_EFL_AF | X86_EFL_ZF | X86_EFL_PF);
+    if (Result.s.Lo & RT_BIT_64(63))
+        *pfEFlags |= X86_EFL_SF;
+    *pfEFlags |= g_afParity[Result.s.Lo & 0xff]; /* (Skylake behaviour) */
+    if (Result.s.Hi != 0)
+        *pfEFlags |= X86_EFL_CF | X86_EFL_OF;
     return 0;
 }