[llvm] r204305 - [X86] Check return value of readSIB in disassembler so errors propagate. In particular this makes a too short instruction with a missing SIB byte fail.

[Craig Topper]

Author: ctopper
Date: Thu Mar 20 00:56:00 2014
New Revision: 204305

URL: http://llvm.org/viewvc/llvm-project?rev=204305&view=rev
Log:
[X86] Check return value of readSIB in disassembler so errors propagate. In particular this makes a too short instruction with a missing SIB byte fail.

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

Modified: llvm/trunk/lib/Target/X86/Disassembler/X86DisassemblerDecoder.c
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Target/X86/Disassembler/X86DisassemblerDecoder.c?rev=204305&r1=204304&r2=204305&view=diff
==============================================================================
--- llvm/trunk/lib/Target/X86/Disassembler/X86DisassemblerDecoder.c (original)
+++ llvm/trunk/lib/Target/X86/Disassembler/X86DisassemblerDecoder.c Thu Mar 20 00:56:00 2014
@@ -1092,7 +1092,6 @@ static int readSIB(struct InternalInstru
   case 2:
     dbgprintf(insn, "SIB-based addressing doesn't work in 16-bit mode");
     return -1;
-    break;
   case 4:
     sibIndexBase = SIB_INDEX_EAX;
     sibBaseBase = SIB_BASE_EAX;
@@ -1314,8 +1313,7 @@ static int readModRM(struct InternalInst
       case 0xc:   /* in case REXW.b is set */
         insn->eaBase = (insn->addressSize == 4 ?
                         EA_BASE_sib : EA_BASE_sib64);
-        readSIB(insn);
-        if (readDisplacement(insn))
+        if (readSIB(insn) || readDisplacement(insn))
           return -1;
         break;
       case 0x5:
@@ -1339,8 +1337,7 @@ static int readModRM(struct InternalInst
       case 0x4:
       case 0xc:   /* in case REXW.b is set */
         insn->eaBase = EA_BASE_sib;
-        readSIB(insn);
-        if (readDisplacement(insn))
+        if (readSIB(insn) || readDisplacement(insn))
           return -1;
         break;
       default: