[mips][microMIPS] Implement LWSP and SWSP instructions

Differential Revision: http://reviews.llvm.org/D6416

llvm-svn: 224771
diff --git a/llvm/lib/Target/Mips/Disassembler/MipsDisassembler.cpp b/llvm/lib/Target/Mips/Disassembler/MipsDisassembler.cpp
index 1b955f5..f4f870b 100644
--- a/llvm/lib/Target/Mips/Disassembler/MipsDisassembler.cpp
+++ b/llvm/lib/Target/Mips/Disassembler/MipsDisassembler.cpp
@@ -265,6 +265,11 @@
                                     uint64_t Address,
                                     const void *Decoder);
 
+static DecodeStatus DecodeMemMMSPImm5Lsl2(MCInst &Inst,
+                                          unsigned Insn,
+                                          uint64_t Address,
+                                          const void *Decoder);
+
 static DecodeStatus DecodeMemMMImm12(MCInst &Inst,
                                      unsigned Insn,
                                      uint64_t Address,
@@ -1197,6 +1202,22 @@
   return MCDisassembler::Success;
 }
 
+static DecodeStatus DecodeMemMMSPImm5Lsl2(MCInst &Inst,
+                                          unsigned Insn,
+                                          uint64_t Address,
+                                          const void *Decoder) {
+  unsigned Offset = Insn & 0x1F;
+  unsigned Reg = fieldFromInstruction(Insn, 5, 5);
+
+  Reg = getReg(Decoder, Mips::GPR32RegClassID, Reg);
+
+  Inst.addOperand(MCOperand::CreateReg(Reg));
+  Inst.addOperand(MCOperand::CreateReg(Mips::SP));
+  Inst.addOperand(MCOperand::CreateImm(Offset << 2));
+
+  return MCDisassembler::Success;
+}
+
 static DecodeStatus DecodeMemMMImm12(MCInst &Inst,
                                      unsigned Insn,
                                      uint64_t Address,