commit 67d18be2a5bddbd8ee9ef144b34ccaeba08a1db2
author Mark Mendell <mark.p.mendell@intel.com> Fri May 30 15:05:09 2014 -0400
committer Ian Rogers <irogers@google.com> Fri May 30 13:04:11 2014 -0700
tree 77a7d6e731f63ec95005e52261585d1b93324929
parent b413cd79c46b7c48ac763cb8152a55a4ed60fe9f

Support disassembly of 16-bit immediates

Change-Id: I66f5ce93077241204311e52c547599f5287bae04
Signed-off-by: Mark Mendell <mark.p.mendell@intel.com>

disassembler/disassembler_x86.cc

diff --git a/disassembler/disassembler_x86.cc b/disassembler/disassembler_x86.cc
index cba4ebf..614eca1 100644
--- a/disassembler/disassembler_x86.cc
+++ b/disassembler/disassembler_x86.cc
@@ -1040,8 +1040,13 @@
       instr++;
     } else {
       CHECK_EQ(immediate_bytes, 4u);
-      args << StringPrintf("%d", *reinterpret_cast<const int32_t*>(instr));
-      instr += 4;
+      if (prefix[2] == 0x66) {  // Operand size override from 32-bit to 16-bit.
+        args << StringPrintf("%d", *reinterpret_cast<const int16_t*>(instr));
+        instr += 2;
+      } else {
+        args << StringPrintf("%d", *reinterpret_cast<const int32_t*>(instr));
+        instr += 4;
+      }
     }
   } else if (branch_bytes > 0) {
     DCHECK(!has_modrm);