Implement microMIPS 16-bit unconditional branch instruction B.
Implemented 16-bit microMIPS unconditional instruction has real name B16, and
B is an alias which expands to either B16 or BEQ according to the rules:
b 256 --> b16 256 # R_MICROMIPS_PC10_S1
b 12256 --> beq $zero, $zero, 12256 # R_MICROMIPS_PC16_S1
b label --> beq $zero, $zero, label # R_MICROMIPS_PC16_S1
Differential Revision: http://reviews.llvm.org/D3514
llvm-svn: 226657
bool expandLoadAddressReg(MCInst &Inst, SMLoc IDLoc,
SmallVectorImpl<MCInst> &Instructions);
+ bool expandUncondBranchMMPseudo(MCInst &Inst, SMLoc IDLoc,
+ SmallVectorImpl<MCInst> &Instructions);
void expandLoadAddressSym(MCInst &Inst, SMLoc IDLoc,
SmallVectorImpl<MCInst> &Instructions);
case Mips::LoadAddr32Imm:
case Mips::LoadAddr32Reg:
case Mips::LoadImm64Reg:
+ case Mips::B_MM_Pseudo:
return true;
default:
return false;
return expandLoadAddressImm(Inst, IDLoc, Instructions);
case Mips::LoadAddr32Reg:
return expandLoadAddressReg(Inst, IDLoc, Instructions);
+ case Mips::B_MM_Pseudo:
+ return expandUncondBranchMMPseudo(Inst, IDLoc, Instructions);
}
}
}
}
+bool MipsAsmParser::
+expandUncondBranchMMPseudo(MCInst &Inst, SMLoc IDLoc,
+ SmallVectorImpl<MCInst> &Instructions) {
+ const MCInstrDesc &MCID = getInstDesc(Inst.getOpcode());
+
+ assert(MCID.getNumOperands() == 1 && "unexpected number of operands");
+
+ MCOperand Offset = Inst.getOperand(0);
+ if (Offset.isExpr()) {
+ Inst.clear();
+ Inst.setOpcode(Mips::BEQ_MM);
+ Inst.addOperand(MCOperand::CreateReg(Mips::ZERO));
+ Inst.addOperand(MCOperand::CreateReg(Mips::ZERO));
+ Inst.addOperand(MCOperand::CreateExpr(Offset.getExpr()));
+ } else {
+ assert(Offset.isImm() && "expected immediate operand kind");
+ if (isIntN(11, Offset.getImm())) {
+ // If offset fits into 11 bits then this instruction becomes microMIPS
+ // 16-bit unconditional branch instruction.
+ Inst.setOpcode(Mips::B16_MM);
+ } else {
+ if (!isIntN(17, Offset.getImm()))
+ Error(IDLoc, "branch target out of range");
+ if (OffsetToAlignment(Offset.getImm(), 1LL << 1))
+ Error(IDLoc, "branch to misaligned address");
+ Inst.clear();
+ Inst.setOpcode(Mips::BEQ_MM);
+ Inst.addOperand(MCOperand::CreateReg(Mips::ZERO));
+ Inst.addOperand(MCOperand::CreateReg(Mips::ZERO));
+ Inst.addOperand(MCOperand::CreateImm(Offset.getImm()));
+ }
+ }
+ Instructions.push_back(Inst);
+
+ if (AssemblerOptions.back()->isReorder()) {
+ // If .set reorder is active, emit a NOP after the branch instruction.
+ MCInst NopInst;
+ NopInst.setOpcode(Mips::MOVE16_MM);
+ NopInst.addOperand(MCOperand::CreateReg(Mips::ZERO));
+ NopInst.addOperand(MCOperand::CreateReg(Mips::ZERO));
+ Instructions.push_back(NopInst);
+ }
+ return false;
+}
+
void MipsAsmParser::expandMemInst(MCInst &Inst, SMLoc IDLoc,
SmallVectorImpl<MCInst> &Instructions,
bool isLoad, bool isImmOpnd) {
uint64_t Address,
const void *Decoder);
+// DecodeBranchTarget10MM - Decode microMIPS branch offset, which is
+// shifted left by 1 bit.
+static DecodeStatus DecodeBranchTarget10MM(MCInst &Inst,
+ unsigned Offset,
+ uint64_t Address,
+ const void *Decoder);
+
// DecodeBranchTargetMM - Decode microMIPS branch offset, which is
// shifted left by 1 bit.
static DecodeStatus DecodeBranchTargetMM(MCInst &Inst,
return MCDisassembler::Success;
}
+static DecodeStatus DecodeBranchTarget10MM(MCInst &Inst,
+ unsigned Offset,
+ uint64_t Address,
+ const void *Decoder) {
+ int32_t BranchOffset = SignExtend32<10>(Offset) << 1;
+ Inst.addOperand(MCOperand::CreateImm(BranchOffset));
+ return MCDisassembler::Success;
+}
+
static DecodeStatus DecodeBranchTargetMM(MCInst &Inst,
unsigned Offset,
uint64_t Address,
bool MipsInstPrinter::printAlias(const MCInst &MI, raw_ostream &OS) {
switch (MI.getOpcode()) {
case Mips::BEQ:
+ case Mips::BEQ_MM:
// beq $zero, $zero, $L2 => b $L2
// beq $r0, $zero, $L2 => beqz $r0, $L2
return (isReg<Mips::ZERO>(MI, 0) && isReg<Mips::ZERO>(MI, 1) &&
if (!isIntN(7, Value) && Ctx)
Ctx->FatalError(Fixup.getLoc(), "out of range PC7 fixup");
break;
+ case Mips::fixup_MICROMIPS_PC10_S1:
+ Value -= 2;
+ // Forcing a signed division because Value can be negative.
+ Value = (int64_t) Value / 2;
+ // We now check if Value can be encoded as a 10-bit signed immediate.
+ if (!isIntN(10, Value) && Ctx)
+ Ctx->FatalError(Fixup.getLoc(), "out of range PC10 fixup");
+ break;
case Mips::fixup_MICROMIPS_PC16_S1:
Value -= 4;
// Forcing a signed division because Value can be negative.
// microMIPS: x | x | a | b
static bool needsMMLEByteOrder(unsigned Kind) {
- return Kind >= Mips::fixup_MICROMIPS_26_S1 &&
+ return Kind != Mips::fixup_MICROMIPS_PC10_S1 &&
+ Kind >= Mips::fixup_MICROMIPS_26_S1 &&
Kind < Mips::LastTargetFixupKind;
}
switch ((unsigned)Kind) {
case FK_Data_2:
case Mips::fixup_Mips_16:
+ case Mips::fixup_MICROMIPS_PC10_S1:
FullSize = 2;
break;
case FK_Data_8:
{ "fixup_MICROMIPS_LO16", 0, 16, 0 },
{ "fixup_MICROMIPS_GOT16", 0, 16, 0 },
{ "fixup_MICROMIPS_PC7_S1", 0, 7, MCFixupKindInfo::FKF_IsPCRel },
+ { "fixup_MICROMIPS_PC10_S1", 0, 10, MCFixupKindInfo::FKF_IsPCRel },
{ "fixup_MICROMIPS_PC16_S1", 0, 16, MCFixupKindInfo::FKF_IsPCRel },
{ "fixup_MICROMIPS_CALL16", 0, 16, 0 },
{ "fixup_MICROMIPS_GOT_DISP", 0, 16, 0 },
{ "fixup_MICROMIPS_LO16", 16, 16, 0 },
{ "fixup_MICROMIPS_GOT16", 16, 16, 0 },
{ "fixup_MICROMIPS_PC7_S1", 9, 7, MCFixupKindInfo::FKF_IsPCRel },
+ { "fixup_MICROMIPS_PC10_S1", 6, 10, MCFixupKindInfo::FKF_IsPCRel },
{ "fixup_MICROMIPS_PC16_S1",16, 16, MCFixupKindInfo::FKF_IsPCRel },
{ "fixup_MICROMIPS_CALL16", 16, 16, 0 },
{ "fixup_MICROMIPS_GOT_DISP", 16, 16, 0 },
case Mips::fixup_MICROMIPS_PC7_S1:
Type = ELF::R_MICROMIPS_PC7_S1;
break;
+ case Mips::fixup_MICROMIPS_PC10_S1:
+ Type = ELF::R_MICROMIPS_PC10_S1;
+ break;
case Mips::fixup_MICROMIPS_PC16_S1:
Type = ELF::R_MICROMIPS_PC16_S1;
break;
// resulting in - R_MICROMIPS_PC7_S1
fixup_MICROMIPS_PC7_S1,
+ // resulting in - R_MICROMIPS_PC10_S1
+ fixup_MICROMIPS_PC10_S1,
+
// resulting in - R_MICROMIPS_PC16_S1
fixup_MICROMIPS_PC16_S1,
return 0;
}
+/// getBranchTargetOpValueMMPC10 - Return binary encoding of the microMIPS
+/// 10-bit branch target operand. If the machine operand requires relocation,
+/// record the relocation and return zero.
+unsigned MipsMCCodeEmitter::
+getBranchTargetOpValueMMPC10(const MCInst &MI, unsigned OpNo,
+ SmallVectorImpl<MCFixup> &Fixups,
+ const MCSubtargetInfo &STI) const {
+
+ const MCOperand &MO = MI.getOperand(OpNo);
+
+ // If the destination is an immediate, divide by 2.
+ if (MO.isImm()) return MO.getImm() >> 1;
+
+ assert(MO.isExpr() &&
+ "getBranchTargetOpValuePC10 expects only expressions or immediates");
+
+ const MCExpr *Expr = MO.getExpr();
+ Fixups.push_back(MCFixup::Create(0, Expr,
+ MCFixupKind(Mips::fixup_MICROMIPS_PC10_S1)));
+ return 0;
+}
+
/// getBranchTargetOpValue - Return binary encoding of the microMIPS branch
/// target operand. If the machine operand requires relocation,
/// record the relocation and return zero.
SmallVectorImpl<MCFixup> &Fixups,
const MCSubtargetInfo &STI) const;
+ // getBranchTargetOpValueMMPC10 - Return binary encoding of the microMIPS
+ // 10-bit branch target operand. If the machine operand requires relocation,
+ // record the relocation and return zero.
+ unsigned getBranchTargetOpValueMMPC10(const MCInst &MI, unsigned OpNo,
+ SmallVectorImpl<MCFixup> &Fixups,
+ const MCSubtargetInfo &STI) const;
+
// getBranchTargetOpValue - Return binary encoding of the microMIPS branch
// target operand. If the machine operand requires relocation,
// record the relocation and return zero.
let Inst{6-0} = offset;
}
+class B16_FM {
+ bits<10> offset;
+
+ bits<16> Inst;
+
+ let Inst{15-10} = 0x33;
+ let Inst{9-0} = offset;
+}
+
//===----------------------------------------------------------------------===//
// MicroMIPS 32-bit Instruction Formats
//===----------------------------------------------------------------------===//
let ParserMatchClass = MipsJumpTargetAsmOperand;
}
+def brtarget10_mm : Operand<OtherVT> {
+ let EncoderMethod = "getBranchTargetOpValueMMPC10";
+ let OperandType = "OPERAND_PCREL";
+ let DecoderMethod = "DecodeBranchTarget10MM";
+ let ParserMatchClass = MipsJumpTargetAsmOperand;
+}
+
def brtarget_mm : Operand<OtherVT> {
let EncoderMethod = "getBranchTargetOpValueMM";
let OperandType = "OPERAND_PCREL";
let DecoderMethod = "DecodeBranchTargetMM";
+ let ParserMatchClass = MipsJumpTargetAsmOperand;
}
def simm23_lsl2 : Operand<i32> {
let mayLoad = 1;
}
+class UncondBranchMM16<string opstr> :
+ MicroMipsInst16<(outs), (ins brtarget10_mm:$offset),
+ !strconcat(opstr, "\t$offset"),
+ [], IIBranch, FrmI> {
+ let isBranch = 1;
+ let isTerminator = 1;
+ let isBarrier = 1;
+ let hasDelaySlot = 1;
+ let Predicates = [RelocPIC, InMicroMips];
+ let Defs = [AT];
+}
+
def ADDU16_MM : ArithRMM16<"addu16", GPRMM16Opnd, 1, II_ADDU, add>,
ARITH_FM_MM16<0>;
def SUBU16_MM : ArithRMM16<"subu16", GPRMM16Opnd, 0, II_SUBU, sub>,
BEQNEZ_FM_MM16<0x23>;
def BNEZ16_MM : CBranchZeroMM<"bnez16", brtarget7_mm, GPRMM16Opnd>,
BEQNEZ_FM_MM16<0x2b>;
+def B16_MM : UncondBranchMM16<"b16">, B16_FM;
def BREAK16_MM : BrkSdbbp16MM<"break16">, BRKSDBBP16_FM_MM<0x28>;
def SDBBP16_MM : BrkSdbbp16MM<"sdbbp16">, BRKSDBBP16_FM_MM<0x2C>;
// MicroMips instruction aliases
//===----------------------------------------------------------------------===//
+class UncondBranchMMPseudo<string opstr> :
+ MipsAsmPseudoInst<(outs), (ins brtarget_mm:$offset),
+ !strconcat(opstr, "\t$offset")>;
+
+ def B_MM_Pseudo : UncondBranchMMPseudo<"b">;
+
def : MipsInstAlias<"wait", (WAIT_MM 0x0), 1>;
def : MipsInstAlias<"nop", (SLL_MM ZERO, ZERO, 0), 1>;
def : MipsInstAlias<"nop", (MOVE16_MM ZERO, ZERO), 1>;
def : MipsInstAlias<"mtc0 $rt, $rd", (MTC0 GPR32Opnd:$rt, GPR32Opnd:$rd, 0), 0>;
def : MipsInstAlias<"mfc2 $rt, $rd", (MFC2 GPR32Opnd:$rt, GPR32Opnd:$rd, 0), 0>;
def : MipsInstAlias<"mtc2 $rt, $rd", (MTC2 GPR32Opnd:$rt, GPR32Opnd:$rd, 0), 0>;
+let AdditionalPredicates = [NotInMicroMips] in {
def : MipsInstAlias<"b $offset", (BEQ ZERO, ZERO, brtarget:$offset), 0>;
+}
def : MipsInstAlias<"bnez $rs,$offset",
(BNE GPR32Opnd:$rs, ZERO, brtarget:$offset), 0>;
def : MipsInstAlias<"beqz $rs,$offset",
# CHECK: bnez16 $6, 20
0xaf 0x0a
+
+# CHECK: b16 132
+0xcc 0x42
# CHECK: bnez16 $6, 20
0x0a 0xaf
+
+# CHECK: b16 132
+0x42 0xcc
# CHECK-EL: nop # encoding: [0x00,0x00,0x00,0x00]
# CHECK-EL: bnez16 $6, 20 # encoding: [0x0a,0xaf]
# CHECK-EL: nop # encoding: [0x00,0x00,0x00,0x00]
+# CHECK-EL: b16 132 # encoding: [0x42,0xcc]
+# CHECK-EL: nop
+# CHECK-EL: b16 132 # encoding: [0x42,0xcc]
+# CHECK-EL: nop
# CHECK-EL: break16 8 # encoding: [0x88,0x46]
# CHECK-EL: sdbbp16 14 # encoding: [0xce,0x46]
#------------------------------------------------------------------------------
# CHECK-EB: nop # encoding: [0x00,0x00,0x00,0x00]
# CHECK-EB: bnez16 $6, 20 # encoding: [0xaf,0x0a]
# CHECK-EB: nop # encoding: [0x00,0x00,0x00,0x00]
+# CHECK-EB: b16 132 # encoding: [0xcc,0x42]
+# CHECK-EB: nop
+# CHECK-EB: b16 132 # encoding: [0xcc,0x42]
+# CHECK-EB: nop
# CHECK-EB: break16 8 # encoding: [0x46,0x88]
# CHECK-EB: sdbbp16 14 # encoding: [0x46,0xce]
jr16 $9
beqz16 $6, 20
bnez16 $6, 20
+ b 132
+ b16 132
break16 8
sdbbp16 14
# Check that the assembler can handle the documented syntax
# for relocations.
#------------------------------------------------------------------------------
-# CHECK-FIXUP: b bar # encoding: [A,0x94'A',0x00,0x00]
+# CHECK-FIXUP: beqz16 $6, bar # encoding: [0b0AAAAAAA,0x8f]
# CHECK-FIXUP: # fixup A - offset: 0,
-# CHECK-FIXUP: value: bar, kind: fixup_MICROMIPS_PC16_S1
+# CHECK-FIXUP: value: bar, kind: fixup_MICROMIPS_PC7_S1
+# CHECK-FIXUP: nop # encoding: [0x00,0x00,0x00,0x00]
+# CHECK-FIXUP: bnez16 $6, bar # encoding: [0b0AAAAAAA,0xaf]
+# CHECK-FIXUP: # fixup A - offset: 0,
+# CHECK-FIXUP: value: bar, kind: fixup_MICROMIPS_PC7_S1
# CHECK-FIXUP: nop # encoding: [0x00,0x00,0x00,0x00]
+# CHECK-FIXUP: b16 bar # encoding: [A,0b110011AA]
+# CHECK-FIXUP: # fixup A - offset: 0,
+# CHECK-FIXUP: value: bar, kind: fixup_MICROMIPS_PC10_S1
+# CHECK-FIXUP: nop # encoding: [0x00,0x00,0x00,0x00]
+# CHECK-FIXUP: b bar # encoding: [A,0x94'A',0x00,0x00]
+# CHECK-FIXUP: # fixup A - offset: 0,
+# CHECK-FIXUP: value: bar, kind: fixup_MICROMIPS_PC16_S1
+# CHECK-FIXUP: nop # encoding: [0x00,0x0c]
# CHECK-FIXUP: beq $3, $4, bar # encoding: [0x83'A',0x94'A',0x00,0x00]
# CHECK-FIXUP: # fixup A - offset: 0,
# CHECK-FIXUP: value: bar, kind: fixup_MICROMIPS_PC16_S1
# Check that the appropriate relocations were created.
#------------------------------------------------------------------------------
# CHECK-ELF: Relocations [
+# CHECK-ELF: 0x{{[0-9,A-F]+}} R_MICROMIPS_PC7_S1
+# CHECK-ELF: 0x{{[0-9,A-F]+}} R_MICROMIPS_PC7_S1
+# CHECK-ELF: 0x{{[0-9,A-F]+}} R_MICROMIPS_PC10_S1
# CHECK-ELF: 0x{{[0-9,A-F]+}} R_MICROMIPS_PC16_S1
# CHECK-ELF: 0x{{[0-9,A-F]+}} R_MICROMIPS_PC16_S1
# CHECK-ELF: 0x{{[0-9,A-F]+}} R_MICROMIPS_PC16_S1
# CHECK-ELF: 0x{{[0-9,A-F]+}} R_MICROMIPS_PC16_S1
# CHECK-ELF: ]
+ .text
+ .type main, @function
+ .set micromips
+main:
+ beqz16 $6, bar
+ bnez16 $6, bar
+ b16 bar
b bar
beq $3, $4, bar
bne $3, $4, bar
#------------------------------------------------------------------------------
# Little endian
#------------------------------------------------------------------------------
-# CHECK-EL: b 1332 # encoding: [0x00,0x94,0x9a,0x02]
-# CHECK-EL: nop # encoding: [0x00,0x00,0x00,0x00]
+# CHECK-EL: b 1332 # encoding: [0x00,0x94,0x9a,0x02]
+# CHECK-EL: nop # encoding: [0x00,0x0c]
# CHECK-EL: beq $9, $6, 1332 # encoding: [0xc9,0x94,0x9a,0x02]
# CHECK-EL: nop # encoding: [0x00,0x00,0x00,0x00]
# CHECK-EL: bgez $6, 1332 # encoding: [0x46,0x40,0x9a,0x02]
#------------------------------------------------------------------------------
# Big endian
#------------------------------------------------------------------------------
-# CHECK-EB: b 1332 # encoding: [0x94,0x00,0x02,0x9a]
-# CHECK-EB: nop # encoding: [0x00,0x00,0x00,0x00]
+# CHECK-EB: b 1332 # encoding: [0x94,0x00,0x02,0x9a]
+# CHECK-EB: nop # encoding: [0x0c,0x00]
# CHECK-EB: beq $9, $6, 1332 # encoding: [0x94,0xc9,0x02,0x9a]
# CHECK-EB: nop # encoding: [0x00,0x00,0x00,0x00]
# CHECK-EB: bgez $6, 1332 # encoding: [0x40,0x46,0x02,0x9a]
# CHECK-EB: bltzals $6, 1332 # encoding: [0x42,0x26,0x02,0x9a]
# CHECK-EB: nop # encoding: [0x0c,0x00]
+ .text
+ .type main, @function
+ .set micromips
+main:
b 1332
beq $9,$6,1332
bgez $6,1332
+++ /dev/null
-# RUN: llvm-mc %s -triple=mipsel-unknown-linux -show-encoding \
-# RUN: -mattr=micromips | FileCheck %s -check-prefix=CHECK-FIXUP
-# RUN: llvm-mc %s -filetype=obj -triple=mipsel-unknown-linux \
-# RUN: -mattr=micromips | llvm-readobj -r \
-# RUN: | FileCheck %s -check-prefix=CHECK-ELF
-#------------------------------------------------------------------------------
-# Check that the assembler can handle the documented syntax
-# for relocations.
-#------------------------------------------------------------------------------
-# CHECK-FIXUP: beqz16 $6, bar # encoding: [0b0AAAAAAA,0x8f]
-# CHECK-FIXUP: # fixup A - offset: 0,
-# CHECK-FIXUP: value: bar, kind: fixup_MICROMIPS_PC7_S1
-# CHECK-FIXUP: nop # encoding: [0x00,0x00,0x00,0x00]
-# CHECK-FIXUP: bnez16 $6, bar # encoding: [0b0AAAAAAA,0xaf]
-# CHECK-FIXUP: # fixup A - offset: 0,
-# CHECK-FIXUP: value: bar, kind: fixup_MICROMIPS_PC7_S1
-# CHECK-FIXUP: nop # encoding: [0x00,0x00,0x00,0x00]
-#------------------------------------------------------------------------------
-# Check that the appropriate relocations were created.
-#------------------------------------------------------------------------------
-# CHECK-ELF: Relocations [
-# CHECK-ELF: 0x{{[0-9,A-F]+}} R_MICROMIPS_PC7_S1
-# CHECK-ELF: 0x{{[0-9,A-F]+}} R_MICROMIPS_PC7_S1
-# CHECK-ELF: ]
-
- beqz16 $6, bar
- bnez16 $6, bar
.text
b foo
- .space 65536 - 8, 1 # -8 = size of b instr plus size of automatically inserted nop
+ .space 65536 - 6, 1 # -6 = size of b instr plus size of automatically inserted nop
nop # This instr makes the branch too long to fit into a 17-bit offset
foo:
add $0,$0,$0