MicroMIPS Compact Branch Instructions BEQZC and BNEZC

[jkolek]

Summary

Implement microMIPS compact branch instructions BEQZC and BNEZC.

[jkolek]

lib/Target/Mips/MicroMipsInstrInfo.td

32 ↗

(On Diff #8927)

These instructions doesn't have specified selection pattern, the usage implementation is in http://reviews.llvm.org/D3566.

[dsanders]

LGTM

[jkolek]

Closed by commit rL215636 (authored by zjovanovic).

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

class MADDS_FM_MM<bits<6> funct>: MMArch {
 
   let Inst{31-26} = 0x15;
   let Inst{25-21} = ft;
   let Inst{20-16} = fs;
   let Inst{15-11} = fd;
   let Inst{10-6}  = fr;
   let Inst{5-0}   = funct;
 }
+
+class COMPACT_BRANCH_FM_MM<bits<5> funct> {
+  bits<5>  rs;
+  bits<16> offset;
+
+  bits<32> Inst;
+
+  let Inst{31-26} = 0x10;
+  let Inst{25-21} = funct;
+  let Inst{20-16} = rs;
+  let Inst{15-0}  = offset;
+}

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

 }
 
 def brtarget_mm : Operand<OtherVT> {
   let EncoderMethod = "getBranchTargetOpValueMM";
   let OperandType   = "OPERAND_PCREL";
   let DecoderMethod = "DecodeBranchTargetMM";
 }
 
+class CompactBranchMM<string opstr, DAGOperand opnd, PatFrag cond_op,
+                      RegisterOperand RO> :
+  InstSE<(outs), (ins RO:$rs, opnd:$offset),
+         !strconcat(opstr, "\t$rs, $offset"), [], IIBranch, FrmI> {
+  let isBranch = 1;
+  let isTerminator = 1;
+  let hasDelaySlot = 0;
+  let Defs = [AT];
+}
+
 let canFoldAsLoad = 1 in
 class LoadLeftRightMM<string opstr, SDNode OpNode, RegisterOperand RO,
                       Operand MemOpnd> :
   InstSE<(outs RO:$rt), (ins MemOpnd:$addr, RO:$src),
          !strconcat(opstr, "\t$rt, $addr"),
          [(set RO:$rt, (OpNode addrimm12:$addr, RO:$src))],
          NoItinerary, FrmI> {
   let DecoderMethod = "DecodeMemMMImm12";

 def MOVE16_MM : MoveMM16<"move", GPR32Opnd>, MOVE_FM_MM16<0x03>;
 def JALR16_MM : JumpLinkRegMM16<"jalr", GPR32Opnd>, JALR_FM_MM16<0x0e>;
 
 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>,
+                 COMPACT_BRANCH_FM_MM<0x7>;
+  def BNEZC_MM : CompactBranchMM<"bnezc", brtarget_mm, setne, GPR32Opnd>,
+                 COMPACT_BRANCH_FM_MM<0x5>;
+
   /// Arithmetic Instructions (ALU Immediate)
   def ADDiu_MM : MMRel, ArithLogicI<"addiu", simm16, GPR32Opnd>,
                  ADDI_FM_MM<0xc>;
   def ADDi_MM  : MMRel, ArithLogicI<"addi", simm16, GPR32Opnd>,
                  ADDI_FM_MM<0x4>;
   def SLTi_MM  : MMRel, SetCC_I<"slti", setlt, simm16, immSExt16, GPR32Opnd>,
                  SLTI_FM_MM<0x24>;
   def SLTiu_MM : MMRel, SetCC_I<"sltiu", setult, simm16, immSExt16, GPR32Opnd>,