[llvm] r225035 - [x86] Simplify detection of jcxz/jecxz/jrcxz in disassembler.

[Craig Topper]

Author: ctopper
Date: Wed Dec 31 01:07:11 2014
New Revision: 225035

URL: http://llvm.org/viewvc/llvm-project?rev=225035&view=rev
Log:
[x86] Simplify detection of jcxz/jecxz/jrcxz in disassembler.

Modified:
    llvm/trunk/lib/Target/X86/Disassembler/X86DisassemblerDecoder.cpp

Modified: llvm/trunk/lib/Target/X86/Disassembler/X86DisassemblerDecoder.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Target/X86/Disassembler/X86DisassemblerDecoder.cpp?rev=225035&r1=225034&r2=225035&view=diff
==============================================================================
--- llvm/trunk/lib/Target/X86/Disassembler/X86DisassemblerDecoder.cpp (original)
+++ llvm/trunk/lib/Target/X86/Disassembler/X86DisassemblerDecoder.cpp Wed Dec 31 01:07:11 2014
@@ -975,27 +975,16 @@ static int getID(struct InternalInstruct
   if (insn->rexPrefix & 0x08)
     attrMask |= ATTR_REXW;
 
-  if (getIDWithAttrMask(&instructionID, insn, attrMask))
-    return -1;
-
   /*
    * JCXZ/JECXZ need special handling for 16-bit mode because the meaning
    * of the AdSize prefix is inverted w.r.t. 32-bit mode.
    */
-  if (insn->mode == MODE_16BIT && insn->opcode == 0xE3) {
-    const struct InstructionSpecifier *spec;
-    spec = specifierForUID(instructionID);
+  if (insn->mode == MODE_16BIT && insn->opcodeType == ONEBYTE &&
+      insn->opcode == 0xE3)
+    attrMask ^= ATTR_ADSIZE;
 
-    /*
-     * Check for Ii8PCRel instructions. We could alternatively do a
-     * string-compare on the names, but this is probably cheaper.
-     */
-    if (x86OperandSets[spec->operands][0].type == TYPE_REL8) {
-      attrMask ^= ATTR_ADSIZE;
-      if (getIDWithAttrMask(&instructionID, insn, attrMask))
-        return -1;
-    }
-  }
+  if (getIDWithAttrMask(&instructionID, insn, attrMask))
+    return -1;
 
   /* The following clauses compensate for limitations of the tables. */