[MIPS] Modify LongBranch expansion to work with sandboxing

lib/Target/Mips/MipsInstrInfo.td

Index: lib/Target/Mips/MipsInstrInfo.td
diff --git a/lib/Target/Mips/MipsInstrInfo.td b/lib/Target/Mips/MipsInstrInfo.td
index e3180f8f393e972b78a7d24f03af7689e4dccbf1..961859672be80f1594f74eaeb55ff14bf6027715 100644
--- a/lib/Target/Mips/MipsInstrInfo.td
+++ b/lib/Target/Mips/MipsInstrInfo.td
@@ -841,6 +841,16 @@ def SFI_DATA_MASK :
 MipsAsmPseudoInst<(outs CPURegs:$dst), (ins CPURegs:$src1, CPURegs:$src2),
     "sfi_data_mask\t$dst, $src1, $src2">;
 
+// See the comment in MipsLongBranch.cpp why we need these two instructions.
+def NACL_LONG_BRANCH_LUi :
+MipsAsmPseudoInst<(outs CPURegs:$dst), (ins brtarget:$tgt, brtarget:$baltgt),
+    "nacl_long_branch_lui\t$dst, $tgt, $baltgt">;
+
+def NACL_LONG_BRANCH_ADDiu :
+MipsAsmPseudoInst<(outs CPURegs:$dst),
+                  (ins CPURegs:$src, brtarget:$tgt, brtarget:$baltgt),
+    "nacl_long_branch_addiu\t$dst, $src, $tgt, $baltgt">;
+
 // @LOCALMOD-END
 
 // Return RA.