Index: llvm/trunk/lib/Target/Mips/MicroMips32r6InstrFormats.td
===================================================================
--- llvm/trunk/lib/Target/Mips/MicroMips32r6InstrFormats.td
+++ llvm/trunk/lib/Target/Mips/MicroMips32r6InstrFormats.td
@@ -29,3 +29,16 @@
   let Inst{11-6} = funct;
   let Inst{5-0} = 0b111100;
 }
+
+class CACHE_PREF_FM_MMR6<bits<6> opgroup, bits<4> funct> : MipsR6Inst {
+  bits<21> addr;
+  bits<5> hint;
+
+  bits<32> Inst;
+
+  let Inst{31-26} = opgroup;
+  let Inst{25-21} = hint;
+  let Inst{20-16} = addr{20-16};
+  let Inst{15-12} = funct;
+  let Inst{11-0}  = addr{11-0};
+}
Index: llvm/trunk/lib/Target/Mips/MicroMips32r6InstrInfo.td
===================================================================
--- llvm/trunk/lib/Target/Mips/MicroMips32r6InstrInfo.td
+++ llvm/trunk/lib/Target/Mips/MicroMips32r6InstrInfo.td
@@ -20,6 +20,8 @@
 class BALC_MMR6_ENC  : BRANCH_OFF26_FM<0b101101>;
 class BC_MMR6_ENC : BRANCH_OFF26_FM<0b100101>;
 class BITSWAP_MMR6_ENC : POOL32A_BITSWAP_FM_MMR6<0b101100>;
+class CACHE_MMR6_ENC : CACHE_PREF_FM_MMR6<0b001000, 0b0110>;
+class PREF_MMR6_ENC : CACHE_PREF_FM_MMR6<0b011000, 0b0010>;
 
 //===----------------------------------------------------------------------===//
 //
@@ -51,6 +53,18 @@
 
 class BITSWAP_MMR6_DESC : BITSWAP_MMR6_DESC_BASE<"bitswap", GPR32Opnd>;
 
+class CACHE_HINT_MMR6_DESC<string instr_asm, Operand MemOpnd,
+                           RegisterOperand GPROpnd> : MMR6Arch<instr_asm> {
+  dag OutOperandList = (outs);
+  dag InOperandList = (ins MemOpnd:$addr, uimm5:$hint);
+  string AsmString = !strconcat(instr_asm, "\t$hint, $addr");
+  list<dag> Pattern = [];
+  string DecoderMethod = "DecodeCacheOpMM";
+}
+
+class CACHE_MMR6_DESC : CACHE_HINT_MMR6_DESC<"cache", mem_mm_12, GPR32Opnd>;
+class PREF_MMR6_DESC : CACHE_HINT_MMR6_DESC<"pref", mem_mm_12, GPR32Opnd>;
+
 //===----------------------------------------------------------------------===//
 //
 // Instruction Definitions
@@ -62,4 +76,6 @@
 def BC_MMR6 : R6MMR6Rel, BC_MMR6_ENC, BC_MMR6_DESC, ISA_MICROMIPS32R6;
 def BITSWAP_MMR6 : R6MMR6Rel, BITSWAP_MMR6_ENC, BITSWAP_MMR6_DESC,
                    ISA_MICROMIPS32R6;
+def CACHE_MMR6 : R6MMR6Rel, CACHE_MMR6_ENC, CACHE_MMR6_DESC, ISA_MICROMIPS32R6;
+def PREF_MMR6 : R6MMR6Rel, PREF_MMR6_ENC, PREF_MMR6_DESC, ISA_MICROMIPS32R6;
 }
Index: llvm/trunk/lib/Target/Mips/Mips32r6InstrInfo.td
===================================================================
--- llvm/trunk/lib/Target/Mips/Mips32r6InstrInfo.td
+++ llvm/trunk/lib/Target/Mips/Mips32r6InstrInfo.td
@@ -546,7 +546,7 @@
 class CLASS_D_DESC : CLASS_RINT_DESC_BASE<"class.d", FGR64Opnd>;
 
 class CACHE_HINT_DESC<string instr_asm, Operand MemOpnd,
-                      RegisterOperand GPROpnd> {
+                      RegisterOperand GPROpnd> : MipsR6Arch<instr_asm> {
   dag OutOperandList = (outs);
   dag InOperandList = (ins MemOpnd:$addr, uimm5:$hint);
   string AsmString = !strconcat(instr_asm, "\t$hint, $addr");
@@ -677,7 +677,7 @@
 def BNEZC : BNEZC_ENC, BNEZC_DESC, ISA_MIPS32R6;
 def BNVC : BNVC_ENC, BNVC_DESC, ISA_MIPS32R6;
 def BOVC : BOVC_ENC, BOVC_DESC, ISA_MIPS32R6;
-def CACHE_R6 : CACHE_ENC, CACHE_DESC, ISA_MIPS32R6;
+def CACHE_R6 : R6MMR6Rel, CACHE_ENC, CACHE_DESC, ISA_MIPS32R6;
 def CLASS_D : CLASS_D_ENC, CLASS_D_DESC, ISA_MIPS32R6;
 def CLASS_S : CLASS_S_ENC, CLASS_S_DESC, ISA_MIPS32R6;
 def CLO_R6 : CLO_R6_ENC, CLO_R6_DESC, ISA_MIPS32R6;
@@ -714,7 +714,7 @@
 def MUL_R6 : MUL_R6_ENC, MUL_R6_DESC, ISA_MIPS32R6;
 def MULU   : MULU_ENC, MULU_DESC, ISA_MIPS32R6;
 def NAL; // BAL with rd=0
-def PREF_R6 : PREF_ENC, PREF_DESC, ISA_MIPS32R6;
+def PREF_R6 : R6MMR6Rel, PREF_ENC, PREF_DESC, ISA_MIPS32R6;
 def RINT_D : RINT_D_ENC, RINT_D_DESC, ISA_MIPS32R6;
 def RINT_S : RINT_S_ENC, RINT_S_DESC, ISA_MIPS32R6;
 def SC_R6 : SC_R6_ENC, SC_R6_DESC, ISA_MIPS32R6;
Index: llvm/trunk/test/MC/Disassembler/Mips/micromips32r6.txt
===================================================================
--- llvm/trunk/test/MC/Disassembler/Mips/micromips32r6.txt
+++ llvm/trunk/test/MC/Disassembler/Mips/micromips32r6.txt
@@ -8,3 +8,9 @@
 
 # CHECK: bitswap $4, $2
 0x00 0x44 0x0b 0x3c
+
+# CHECK: cache 1, 8($5)
+0x20 0x25 0x60 0x08
+
+# CHECK: pref 1, 8($5)
+0x60 0x25 0x20 0x08
Index: llvm/trunk/test/MC/Mips/micromips32r6/valid.s
===================================================================
--- llvm/trunk/test/MC/Mips/micromips32r6/valid.s
+++ llvm/trunk/test/MC/Mips/micromips32r6/valid.s
@@ -4,3 +4,5 @@
   balc 14572256            # CHECK: balc 14572256       # encoding: [0xb4,0x37,0x96,0xb8]
   bc 14572256              # CHECK: bc 14572256         # encoding: [0x94,0x37,0x96,0xb8]
   bitswap $4, $2           # CHECK: bitswap $4, $2      # encoding: [0x00,0x44,0x0b,0x3c]
+  cache 1, 8($5)           # CHECK: cache 1, 8($5)      # encoding: [0x20,0x25,0x60,0x08]
+  pref 1, 8($5)            # CHECK: pref 1, 8($5)       # encoding: [0x60,0x25,0x20,0x08]