[mips][mips64r6] Add bgec and bgeuc instructions

Differential Revision: http://reviews.llvm.org/D4017


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@210770 91177308-0d34-0410-b5e6-96231b3b80d8

2 files changed, 68 insertions, 6 deletions

diff --git a/lib/Target/Mips/Disassembler/MipsDisassembler.cpp b/lib/Target/Mips/Disassembler/MipsDisassembler.cpp
index b35c18c8f6..54df55cbc8 100644
--- a/lib/Target/Mips/Disassembler/MipsDisassembler.cpp
+++ b/lib/Target/Mips/Disassembler/MipsDisassembler.cpp
@@ -319,6 +319,11 @@ static DecodeStatus
 DecodeBgtzGroupBranch(MCInst &MI, InsnType insn, uint64_t Address,
                       const void *Decoder);
 
+template <typename InsnType>
+static DecodeStatus
+DecodeBlezGroupBranch(MCInst &MI, InsnType insn, uint64_t Address,
+                       const void *Decoder);
+
 namespace llvm {
 extern Target TheMipselTarget, TheMipsTarget, TheMips64Target,
               TheMips64elTarget;
@@ -514,6 +519,7 @@ static DecodeStatus DecodeBlezlGroupBranch(MCInst &MI, InsnType insn,
   InsnType Rs = fieldFromInstruction(insn, 21, 5);
   InsnType Rt = fieldFromInstruction(insn, 16, 5);
   InsnType Imm = SignExtend64(fieldFromInstruction(insn, 0, 16), 16) << 2;
+  bool HasRs = false;
 
   if (Rt == 0)
     return MCDisassembler::Fail;
@@ -521,8 +527,14 @@ static DecodeStatus DecodeBlezlGroupBranch(MCInst &MI, InsnType insn,
     MI.setOpcode(Mips::BLEZC);
   else if (Rs == Rt)
     MI.setOpcode(Mips::BGEZC);
-  else
-    return MCDisassembler::Fail; // FIXME: BGEC is not implemented yet.
+  else {
+    HasRs = true;
+    MI.setOpcode(Mips::BGEC);
+  }
+
+  if (HasRs)
+    MI.addOperand(MCOperand::CreateReg(getReg(Decoder, Mips::GPR32RegClassID,
+                                       Rs)));
 
   MI.addOperand(MCOperand::CreateReg(getReg(Decoder, Mips::GPR32RegClassID,
                                      Rt)));
@@ -614,6 +626,48 @@ static DecodeStatus DecodeBgtzGroupBranch(MCInst &MI, InsnType insn,
   return MCDisassembler::Success;
 }
 
+template <typename InsnType>
+static DecodeStatus DecodeBlezGroupBranch(MCInst &MI, InsnType insn,
+                                           uint64_t Address,
+                                           const void *Decoder) {
+  // If we are called then we can assume that MIPS32r6/MIPS64r6 is enabled
+  // (otherwise we would have matched the BLEZL instruction from the earlier
+  // ISA's instead).
+  //
+  // We have:
+  //    0b000110 sssss ttttt iiiiiiiiiiiiiiii
+  //      Invalid   if rs == 0
+  //      BLEZALC   if rs == 0  && rt != 0
+  //      BGEZALC   if rs == rt && rt != 0
+  //      BGEUC     if rs != rt && rs != 0  && rt != 0
+
+  InsnType Rs = fieldFromInstruction(insn, 21, 5);
+  InsnType Rt = fieldFromInstruction(insn, 16, 5);
+  InsnType Imm = SignExtend64(fieldFromInstruction(insn, 0, 16), 16) << 2;
+  bool HasRs = false;
+
+  if (Rt == 0)
+    return MCDisassembler::Fail;
+  else if (Rs == 0)
+    MI.setOpcode(Mips::BLEZALC);
+  else if (Rs == Rt)
+    MI.setOpcode(Mips::BGEZALC);
+  else {
+    HasRs = true;
+    MI.setOpcode(Mips::BGEUC);
+  }
+
+  if (HasRs)
+    MI.addOperand(MCOperand::CreateReg(getReg(Decoder, Mips::GPR32RegClassID,
+                                       Rs)));
+  MI.addOperand(MCOperand::CreateReg(getReg(Decoder, Mips::GPR32RegClassID,
+                                     Rt)));
+
+  MI.addOperand(MCOperand::CreateImm(Imm));
+
+  return MCDisassembler::Success;
+}
+
   /// readInstruction - read four bytes from the MemoryObject
   /// and return 32 bit word sorted according to the given endianess
 static DecodeStatus readInstruction32(const MemoryObject &region,
diff --git a/lib/Target/Mips/Mips32r6InstrInfo.td b/lib/Target/Mips/Mips32r6InstrInfo.td
index 975f612b59..a7a40b5855 100644
--- a/lib/Target/Mips/Mips32r6InstrInfo.td
+++ b/lib/Target/Mips/Mips32r6InstrInfo.td
@@ -93,6 +93,10 @@ class BNEZALC_ENC : CMP_BRANCH_1R_RT_OFF16_FM<OPGROUP_DADDI>,
 
 class BLTZC_ENC : CMP_BRANCH_1R_BOTH_OFF16_FM<OPGROUP_BGTZL>,
                   DecodeDisambiguates<"BgtzlGroupBranch">;
+class BGEC_ENC  : CMP_BRANCH_2R_OFF16_FM<OPGROUP_BLEZL>,
+                  DecodeDisambiguatedBy<"BlezlGroupBranch">;
+class BGEUC_ENC : CMP_BRANCH_2R_OFF16_FM<OPGROUP_BLEZ>,
+                  DecodeDisambiguatedBy<"BlezGroupBranch">;
 class BGEZC_ENC : CMP_BRANCH_1R_BOTH_OFF16_FM<OPGROUP_BLEZL>,
                   DecodeDisambiguates<"BlezlGroupBranch">;
 class BGTZALC_ENC : CMP_BRANCH_1R_RT_OFF16_FM<OPGROUP_BGTZ>,
@@ -106,7 +110,8 @@ class BGTZC_ENC : CMP_BRANCH_1R_RT_OFF16_FM<OPGROUP_BGTZL>,
                   DecodeDisambiguatedBy<"BgtzlGroupBranch">;
 
 class BEQZC_ENC : CMP_BRANCH_OFF21_FM<0b110110>;
-class BGEZALC_ENC : CMP_BRANCH_1R_BOTH_OFF16_FM<OPGROUP_BLEZ>;
+class BGEZALC_ENC : CMP_BRANCH_1R_BOTH_OFF16_FM<OPGROUP_BLEZ>,
+                    DecodeDisambiguates<"BlezGroupBranch">;
 class BNEZC_ENC : CMP_BRANCH_OFF21_FM<0b111110>;
 
 class BC1EQZ_ENC : COP1_BCCZ_FM<OPCODE5_BC1EQZ>;
@@ -118,7 +123,8 @@ class JIALC_ENC : JMP_IDX_COMPACT_FM<0b111110>;
 class JIC_ENC   : JMP_IDX_COMPACT_FM<0b110110>;
 class JR_HB_R6_ENC : JR_HB_R6_FM<OPCODE6_JALR>;
 class BITSWAP_ENC : SPECIAL3_2R_FM<OPCODE6_BITSWAP>;
-class BLEZALC_ENC : CMP_BRANCH_1R_RT_OFF16_FM<OPGROUP_BLEZ>;
+class BLEZALC_ENC : CMP_BRANCH_1R_RT_OFF16_FM<OPGROUP_BLEZ>,
+                    DecodeDisambiguatedBy<"BlezGroupBranch">;
 class BNVC_ENC   : CMP_BRANCH_2R_OFF16_FM<OPGROUP_DADDI>,
                    DecodeDisambiguatedBy<"DaddiGroupBranch">;
 class BOVC_ENC   : CMP_BRANCH_2R_OFF16_FM<OPGROUP_ADDI>,
@@ -321,6 +327,8 @@ class BALC_DESC : BC_DESC_BASE<"balc", brtarget26> {
 }
 
 class BC_DESC : BC_DESC_BASE<"bc", brtarget26>;
+class BGEC_DESC : CMP_BC_DESC_BASE<"bgec", brtarget, GPR32Opnd>;
+class BGEUC_DESC : CMP_BC_DESC_BASE<"bgeuc", brtarget, GPR32Opnd>;
 class BEQC_DESC : CMP_BC_DESC_BASE<"beqc", brtarget, GPR32Opnd>;
 class BNEC_DESC : CMP_BC_DESC_BASE<"bnec", brtarget, GPR32Opnd>;
 
@@ -535,8 +543,8 @@ def BC : BC_ENC, BC_DESC, ISA_MIPS32R6;
 def BEQC : BEQC_ENC, BEQC_DESC, ISA_MIPS32R6;
 def BEQZALC : BEQZALC_ENC, BEQZALC_DESC, ISA_MIPS32R6;
 def BEQZC : BEQZC_ENC, BEQZC_DESC, ISA_MIPS32R6;
-def BGEC;  // Also aliased to blec with operands swapped
-def BGEUC; // Also aliased to bleuc with operands swapped
+def BGEC : BGEC_ENC, BGEC_DESC, ISA_MIPS32R6;
+def BGEUC : BGEUC_ENC, BGEUC_DESC, ISA_MIPS32R6;
 def BGEZALC : BGEZALC_ENC, BGEZALC_DESC, ISA_MIPS32R6;
 def BGEZC : BGEZC_ENC, BGEZC_DESC, ISA_MIPS32R6;
 def BGTZALC : BGTZALC_ENC, BGTZALC_DESC, ISA_MIPS32R6;