[mips] Restore the availablity of trap for microMIPS

[atanasyan]

LGTM

llvm/trunk/lib/Target/Mips/MicroMipsInstrInfo.td

let DecoderNamespace = "MicroMips" in {
   def ERET_MM    : MMRel, ER_FT<"eret", II_ERET>, ER_FM_MM<0x3cd>,
                    ISA_MICROMIPS;
   def DERET_MM   : MMRel, ER_FT<"deret", II_DERET>, ER_FM_MM<0x38d>,
                    ISA_MICROMIPS;
   def EI_MM      : MMRel, DEI_FT<"ei", GPR32Opnd, II_EI>, EI_FM_MM<0x15d>,
                    ISA_MICROMIPS;
   def DI_MM      : MMRel, DEI_FT<"di", GPR32Opnd, II_DI>, EI_FM_MM<0x11d>,
                    ISA_MICROMIPS;
+  def TRAP_MM    : TrapBase<BREAK_MM>, ISA_MICROMIPS;
 
   /// Trap Instructions
   def TEQ_MM  : MMRel, TEQ_FT<"teq", GPR32Opnd, uimm4, II_TEQ>, TEQ_FM_MM<0x0>,
                 ISA_MICROMIPS;
   def TGE_MM  : MMRel, TEQ_FT<"tge", GPR32Opnd, uimm4, II_TGE>, TEQ_FM_MM<0x08>,
                 ISA_MICROMIPS;
   def TGEU_MM : MMRel, TEQ_FT<"tgeu", GPR32Opnd, uimm4, II_TGEU>,
                 TEQ_FM_MM<0x10>, ISA_MICROMIPS;

llvm/trunk/test/CodeGen/Mips/llvm-ir/trap.ll

+; NOTE: Assertions have been autogenerated by utils/update_llc_test_checks.py
+; RUN: llc -mtriple=mips-mti-linux-gnu < %s --show-mc-encoding | FileCheck %s --check-prefix=MTI
+; RUN: llc -mtriple=mips-mti-linux-gnu -mattr=+micromips < %s --show-mc-encoding | FileCheck %s --check-prefix=MM
+; RUN: llc -mtriple=mips-img-linux-gnu < %s --show-mc-encoding | FileCheck %s --check-prefix=IMG
+; RUN: llc -mtriple=mips-img-linux-gnu -mattr=+micromips < %s --show-mc-encoding | FileCheck %s --check-prefix=MMR6
+
+define void @test() noreturn nounwind  {
+; MTI-LABEL: test:
+; MTI:       # %bb.0: # %entry
+; MTI-NEXT:    break # encoding: [0x00,0x00,0x00,0x0d]
+; MTI-NEXT:    jr $ra # encoding: [0x03,0xe0,0x00,0x08]
+; MTI-NEXT:    nop # encoding: [0x00,0x00,0x00,0x00]
+;
+; MM-LABEL: test:
+; MM:       # %bb.0: # %entry
+; MM-NEXT:    break # encoding: [0x00,0x00,0x00,0x07]
+; MM-NEXT:    jrc $ra # encoding: [0x45,0xbf]
+;
+; IMG-LABEL: test:
+; IMG:       # %bb.0: # %entry
+; IMG-NEXT:    break # encoding: [0x00,0x00,0x00,0x0d]
+; IMG-NEXT:    jr $ra # encoding: [0x03,0xe0,0x00,0x08]
+; IMG-NEXT:    nop # encoding: [0x00,0x00,0x00,0x00]
+;
+; MMR6-LABEL: test:
+; MMR6:       # %bb.0: # %entry
+; MMR6-NEXT:    break # encoding: [0x00,0x00,0x00,0x07]
+; MMR6-NEXT:    jrc $ra # encoding: [0x45,0xbf]
+entry:
+  tail call void @llvm.trap( )
+  ret void
+}
+
+declare void @llvm.trap() nounwind