Change unsigned to a uint16_t in static disassembler tables to reduce the table size.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@163594 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/utils/TableGen/X86DisassemblerTables.cpp b/utils/TableGen/X86DisassemblerTables.cpp
index f3bd373..8526621 100644
--- a/utils/TableGen/X86DisassemblerTables.cpp
+++ b/utils/TableGen/X86DisassemblerTables.cpp
@@ -366,6 +366,10 @@
       break;
   }
 
+  // We assume that the index can fit into uint16_t.
+  assert(sEntryNumber < 65536U &&
+         "Index into ModRMDecision is too large for uint16_t!");
+
   ++sTableNumber;
 }