X86: Don't treat the REX prefixes as prefixes in 32 bit modes. These are inc/dec instructions.

2009-02-27 09:26:09 -08:00
parent aa51c01d69
commit 27b751ec46
1 changed files with 4 additions and 1 deletions
--- a/src/arch/x86/predecoder.cc
+++ b/src/arch/x86/predecoder.cc
@@ -136,7 +136,10 @@ namespace X86ISA
    {
        uint8_t prefix = Prefixes[nextByte];
        State nextState = PrefixState;
-        if(prefix)
+        // REX prefixes are only recognized in 64 bit mode.
+        if (prefix == RexPrefix && emi.mode.submode != SixtyFourBitMode)
+            prefix = 0;
+        if (prefix)
            consumeByte();
        switch(prefix)
        {