[mips] Implement ehb, ssnop, and pause in assembler

Summary: Add negative tests for pause

Reviewers: matheusalmeida

Reviewed By: matheusalmeida

Differential Revision: http://llvm-reviews.chandlerc.com/D3246

llvm-svn: 205537

2 files changed, 17 insertions, 0 deletions

diff --git a/llvm/lib/Target/Mips/MipsInstrFormats.td b/llvm/lib/Target/Mips/MipsInstrFormats.td
index 38fac886048..e4405abe908 100644
--- a/llvm/lib/Target/Mips/MipsInstrFormats.td
+++ b/llvm/lib/Target/Mips/MipsInstrFormats.td
@@ -818,3 +818,14 @@ class CMov_F_F_FM<bits<5> fmt, bit tf> : StdArch {
   let Inst{10-6} = fd;
   let Inst{5-0} = 0x11;
 }
+
+class BARRIER_FM<bits<5> op> : StdArch {
+  bits<32> Inst;
+
+  let Inst{31-26} = 0; // SPECIAL
+  let Inst{25-21} = 0;
+  let Inst{20-16} = 0; // rt = 0
+  let Inst{15-11} = 0; // rd = 0
+  let Inst{10-6} = op; // Operation
+  let Inst{5-0} = 0;   // SLL
+}
diff --git a/llvm/lib/Target/Mips/MipsInstrInfo.td b/llvm/lib/Target/Mips/MipsInstrInfo.td
index 9b2e0808938..07c37d87a26 100644
--- a/llvm/lib/Target/Mips/MipsInstrInfo.td
+++ b/llvm/lib/Target/Mips/MipsInstrInfo.td
@@ -1161,6 +1161,12 @@ def MTC0 : MFC3OP<"mtc0", GPR32Opnd>, MFC3OP_FM<0x10, 4>;
 def MFC2 : MFC3OP<"mfc2", GPR32Opnd>, MFC3OP_FM<0x12, 0>;
 def MTC2 : MFC3OP<"mtc2", GPR32Opnd>, MFC3OP_FM<0x12, 4>;
 
+class Barrier<string asmstr> : InstSE<(outs), (ins), asmstr, [], NoItinerary,
+                                      FrmOther>;
+def SSNOP : Barrier<"ssnop">, BARRIER_FM<1>;
+def EHB : Barrier<"ehb">, BARRIER_FM<3>;
+def PAUSE : Barrier<"pause">, BARRIER_FM<5>, Requires<[HasMips32r2]>;
+
 //===----------------------------------------------------------------------===//
 // Instruction aliases
 //===----------------------------------------------------------------------===//