[mips][microMIPS] Implement BREAK16 and SDBBP16 instructions

[sstankovic]

LGTM

[jkolek]

Closed by commit rL222900 (authored by @jkolek).

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

class ADDIUR1SP_FM_MM16 {
   bits<16> Inst;
 
   let Inst{15-10} = 0x1b;
   let Inst{9-7}   = rd;
   let Inst{6-1}   = imm;
   let Inst{0}     = 1;
 }
 
+class BRKSDBBP16_FM_MM<bits<6> op> {
+  bits<4> code_;
+  bits<16> Inst;
+
+  let Inst{15-10} = 0x11;
+  let Inst{9-4}   = op;
+  let Inst{3-0}   = code_;
+}
+
 //===----------------------------------------------------------------------===//
 // MicroMIPS 32-bit Instruction Formats
 //===----------------------------------------------------------------------===//
 
 class MMArch {
   string Arch = "micromips";
   list<dag> Pattern = [];
 }

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

class JumpRegCMM16<string opstr, RegisterOperand RO> :
   MicroMipsInst16<(outs), (ins RO:$rs), !strconcat(opstr, "\t$rs"),
                   [], IIBranch, FrmR> {
   let isTerminator = 1;
   let isBarrier = 1;
   let isBranch = 1;
   let isIndirectBranch = 1;
 }
 
+// Break16 and Sdbbp16
+class BrkSdbbp16MM<string opstr> :
+  MicroMipsInst16<(outs), (ins uimm4:$code_),
+                  !strconcat(opstr, "\t$code_"),
+                  [], NoItinerary, FrmOther>;
+
 // MicroMIPS Jump and Link (Call) - Short Delay Slot
 let isCall = 1, hasDelaySlot = 1, Defs = [RA] in {
   class JumpLinkMM<string opstr, DAGOperand opnd> :
     InstSE<(outs), (ins opnd:$target), !strconcat(opstr, "\t$target"),
            [], IIBranch, FrmJ, opstr> {
     let DecoderMethod = "DecodeJumpTargetMM";
   }
 

 def MOVE16_MM : MoveMM16<"move", GPR32Opnd>, MOVE_FM_MM16<0x03>;
 def LI16_MM : LoadImmMM16<"li16", li_simm7, GPRMM16Opnd, immLi16>,
               LI_FM_MM16, IsAsCheapAsAMove;
 def JALR16_MM : JumpLinkRegMM16<"jalr", GPR32Opnd>, JALR_FM_MM16<0x0e>;
 def JALRS16_MM : JumpLinkRegSMM16<"jalrs16", GPR32Opnd>, JALR_FM_MM16<0x0f>;
 def JRC16_MM : JumpRegCMM16<"jrc", GPR32Opnd>, JALR_FM_MM16<0x0d>;
 def JRADDIUSP : JumpRAddiuStackMM16, JRADDIUSP_FM_MM16<0x18>;
 def JR16_MM : JumpRegMM16<"jr16", GPR32Opnd>, JALR_FM_MM16<0x0c>;
+def BREAK16_MM : BrkSdbbp16MM<"break16">, BRKSDBBP16_FM_MM<0x28>;
+def SDBBP16_MM : BrkSdbbp16MM<"sdbbp16">, BRKSDBBP16_FM_MM<0x2C>;
 
 class WaitMM<string opstr> :
   InstSE<(outs), (ins uimm10:$code_), !strconcat(opstr, "\t$code_"), [],
          NoItinerary, FrmOther, opstr>;
 
 let DecoderNamespace = "MicroMips", Predicates = [InMicroMips] in {
   /// Compact Branch Instructions
   def BEQZC_MM : CompactBranchMM<"beqzc", brtarget_mm, seteq, GPR32Opnd>,

llvm/trunk/test/MC/Mips/micromips-16-bit-instructions.s

 # CHECK-EL: move    $25, $1         # encoding: [0x21,0x0f]
 # CHECK-EL: jrc     $9              # encoding: [0xa9,0x45]
 # CHECK-NEXT: jalr    $9            # encoding: [0xc9,0x45]
 # CHECK-EL: jraddiusp 20            # encoding: [0x05,0x47]
 # CHECK-NEXT: jalrs16 $9            # encoding: [0xe9,0x45]
 # CHECK-EL: move    $zero, $zero    # encoding: [0x00,0x0c]
 # CHECK-EL: jr16    $9              # encoding: [0x89,0x45]
 # CHECK-EL: nop                     # encoding: [0x00,0x00,0x00,0x00]
+# CHECK-EL: break16 8               # encoding: [0x88,0x46]
+# CHECK-EL: sdbbp16 14              # encoding: [0xce,0x46]
 #------------------------------------------------------------------------------
 # Big endian
 #------------------------------------------------------------------------------
 # CHECK-EB: addu16  $6, $17, $4     # encoding: [0x07,0x42]
 # CHECK-EB: subu16  $5, $16, $3     # encoding: [0x06,0xb1]
 # CHECK-EB: andi16  $16, $2, 31     # encoding: [0x2c,0x29]
 # CHECK-EB: and16   $16, $2         # encoding: [0x44,0x82]
 # CHECK-EB: not16   $17, $3         # encoding: [0x44,0x0b]

 # CHECK-EB: move    $25, $1         # encoding: [0x0f,0x21]
 # CHECK-EB: jrc     $9              # encoding: [0x45,0xa9]
 # CHECK-NEXT: jalr    $9            # encoding: [0x45,0xc9]
 # CHECK-EB: jraddiusp 20            # encoding: [0x47,0x05]
 # CHECK-NEXT: jalrs16 $9            # encoding: [0x45,0xe9]
 # CHECK-EB: move    $zero, $zero    # encoding: [0x0c,0x00]
 # CHECK-EB: jr16    $9              # encoding: [0x45,0x89]
 # CHECK-EB: nop                     # encoding: [0x00,0x00,0x00,0x00]
+# CHECK-EB: break16 8               # encoding: [0x46,0x88]
+# CHECK-EB: sdbbp16 14              # encoding: [0x46,0xce]
 
     addu16  $6, $17, $4
     subu16  $5, $16, $3
     andi16  $16, $2, 31
     and16   $16, $2
     not16   $17, $3
     or16    $16, $4
     xor16   $17, $5
# CHECK-EB: sdbbp16 14              # encoding: [0x46,0xce]
     mfhi    $9
     mflo    $9
     move    $25, $1
     jrc     $9
     jalr    $9
     jraddiusp 20
     jalrs16 $9
     jr16    $9
+    break16 8
+    sdbbp16 14