[mips] Added support for assembling sdbbp.

Summary:
This instruction is re-encoded in MIPS32r6/MIPS64r6 without changing the
restrictions. We hadn't implemented it for earlier ISA's so it has been added to those too.

Differential Revision: http://reviews.llvm.org/D4265

llvm-svn: 211590

1 files changed, 10 insertions, 0 deletions

diff --git a/llvm/lib/Target/Mips/MipsInstrFormats.td b/llvm/lib/Target/Mips/MipsInstrFormats.td
index a708e307f3f..6a01ae560f3 100644
--- a/llvm/lib/Target/Mips/MipsInstrFormats.td
+++ b/llvm/lib/Target/Mips/MipsInstrFormats.td
@@ -844,6 +844,16 @@ class BARRIER_FM<bits<5> op> : StdArch {
   let Inst{5-0} = 0;   // SLL
 }
 
+class SDBBP_FM : StdArch {
+  bits<20> code_;
+
+  bits<32> Inst;
+
+  let Inst{31-26} = 0b011100; // SPECIAL2
+  let Inst{25-6} = code_;
+  let Inst{5-0} = 0b111111;   // SDBBP
+}
+
 class JR_HB_FM<bits<6> op> : StdArch{
   bits<5> rs;