diff --git a/include/opcode/ChangeLog b/include/opcode/ChangeLog
index 6a0e469903..875c62684e 100644
--- a/include/opcode/ChangeLog
+++ b/include/opcode/ChangeLog
@@ -1,3 +1,11 @@
+start-sanitize-sky
+Wed Dec  9 15:44:14 1998  Doug Evans  <devans@canuck.cygnus.com>
+
+	Thu Nov 19 16:39:45 EST 1998 Frank Ch. Eigler <fche@cygnus.com>
+
+	* mips.h (INSN_SYNC): New flag.
+
+end-sanitize-sky
 Wed Dec  9 10:38:48 1998  David Taylor  <taylor@texas.cygnus.com>
 
 	The following is part of a change made by Edith Epstein
diff --git a/include/opcode/mips.h b/include/opcode/mips.h
index acd3f4ea93..16851c1b5e 100644
--- a/include/opcode/mips.h
+++ b/include/opcode/mips.h
@@ -234,7 +234,7 @@ start-sanitize-cygnus
    see also "k" above
 end-sanitize-cygnus
 start-sanitize-r5900
-   "0" ???
+   "0" vu0 immediate for viaddi
    "1" vu0 fp reg position 1
    "2" vu0 fp reg position 2
    "3" vu0 fp reg position 3
@@ -252,7 +252,7 @@ start-sanitize-r5900
    "Q" vu0 Q register
    "X" vu0 R register
    "U" vu0 ACC register
-   "O" ???
+   "O" Immediate operand for vcallms instruction.
 end-sanitize-r5900
 
    Macro instructions:
@@ -350,6 +350,8 @@ end-sanitize-r5900
 #define FP_D			    0x20000000
 /* Instruction is part of the tx39's integer multiply family.    */
 #define INSN_MULT                   0x40000000
+/* Instruction synchronize shared memory.  */
+#define INSN_SYNC		    0x80000000
 
 /* Instruction is actually a macro.  It should be ignored by the
    disassembler, and requires special treatment by the assembler.  */