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-rw-r--r--llvm/lib/Target/AArch64/AArch64ISelLowering.cpp87
1 files changed, 54 insertions, 33 deletions
diff --git a/llvm/lib/Target/AArch64/AArch64ISelLowering.cpp b/llvm/lib/Target/AArch64/AArch64ISelLowering.cpp
index 2232e419a61..f0fb03451b2 100644
--- a/llvm/lib/Target/AArch64/AArch64ISelLowering.cpp
+++ b/llvm/lib/Target/AArch64/AArch64ISelLowering.cpp
@@ -4380,46 +4380,57 @@ SDValue AArch64TargetLowering::LowerShiftRightParts(SDValue Op,
SDValue ShOpLo = Op.getOperand(0);
SDValue ShOpHi = Op.getOperand(1);
SDValue ShAmt = Op.getOperand(2);
- SDValue ARMcc;
unsigned Opc = (Op.getOpcode() == ISD::SRA_PARTS) ? ISD::SRA : ISD::SRL;
assert(Op.getOpcode() == ISD::SRA_PARTS || Op.getOpcode() == ISD::SRL_PARTS);
SDValue RevShAmt = DAG.getNode(ISD::SUB, dl, MVT::i64,
DAG.getConstant(VTBits, dl, MVT::i64), ShAmt);
- SDValue Tmp1 = DAG.getNode(ISD::SRL, dl, VT, ShOpLo, ShAmt);
+ SDValue HiBitsForLo = DAG.getNode(ISD::SHL, dl, VT, ShOpHi, RevShAmt);
+
+ // Unfortunately, if ShAmt == 0, we just calculated "(SHL ShOpHi, 64)" which
+ // is "undef". We wanted 0, so CSEL it directly.
+ SDValue Cmp = emitComparison(ShAmt, DAG.getConstant(0, dl, MVT::i64),
+ ISD::SETEQ, dl, DAG);
+ SDValue CCVal = DAG.getConstant(AArch64CC::EQ, dl, MVT::i32);
+ HiBitsForLo =
+ DAG.getNode(AArch64ISD::CSEL, dl, VT, DAG.getConstant(0, dl, MVT::i64),
+ HiBitsForLo, CCVal, Cmp);
+
SDValue ExtraShAmt = DAG.getNode(ISD::SUB, dl, MVT::i64, ShAmt,
DAG.getConstant(VTBits, dl, MVT::i64));
- SDValue Tmp2 = DAG.getNode(ISD::SHL, dl, VT, ShOpHi, RevShAmt);
- SDValue Cmp = emitComparison(ExtraShAmt, DAG.getConstant(0, dl, MVT::i64),
- ISD::SETGE, dl, DAG);
- SDValue CCVal = DAG.getConstant(AArch64CC::GE, dl, MVT::i32);
+ SDValue LoBitsForLo = DAG.getNode(ISD::SRL, dl, VT, ShOpLo, ShAmt);
+ SDValue LoForNormalShift =
+ DAG.getNode(ISD::OR, dl, VT, LoBitsForLo, HiBitsForLo);
- SDValue FalseValLo = DAG.getNode(ISD::OR, dl, VT, Tmp1, Tmp2);
- SDValue TrueValLo = DAG.getNode(Opc, dl, VT, ShOpHi, ExtraShAmt);
- SDValue Lo =
- DAG.getNode(AArch64ISD::CSEL, dl, VT, TrueValLo, FalseValLo, CCVal, Cmp);
+ Cmp = emitComparison(ExtraShAmt, DAG.getConstant(0, dl, MVT::i64), ISD::SETGE,
+ dl, DAG);
+ CCVal = DAG.getConstant(AArch64CC::GE, dl, MVT::i32);
+ SDValue LoForBigShift = DAG.getNode(Opc, dl, VT, ShOpHi, ExtraShAmt);
+ SDValue Lo = DAG.getNode(AArch64ISD::CSEL, dl, VT, LoForBigShift,
+ LoForNormalShift, CCVal, Cmp);
// AArch64 shifts larger than the register width are wrapped rather than
// clamped, so we can't just emit "hi >> x".
- SDValue FalseValHi = DAG.getNode(Opc, dl, VT, ShOpHi, ShAmt);
- SDValue TrueValHi = Opc == ISD::SRA
- ? DAG.getNode(Opc, dl, VT, ShOpHi,
- DAG.getConstant(VTBits - 1, dl,
- MVT::i64))
- : DAG.getConstant(0, dl, VT);
- SDValue Hi =
- DAG.getNode(AArch64ISD::CSEL, dl, VT, TrueValHi, FalseValHi, CCVal, Cmp);
+ SDValue HiForNormalShift = DAG.getNode(Opc, dl, VT, ShOpHi, ShAmt);
+ SDValue HiForBigShift =
+ Opc == ISD::SRA
+ ? DAG.getNode(Opc, dl, VT, ShOpHi,
+ DAG.getConstant(VTBits - 1, dl, MVT::i64))
+ : DAG.getConstant(0, dl, VT);
+ SDValue Hi = DAG.getNode(AArch64ISD::CSEL, dl, VT, HiForBigShift,
+ HiForNormalShift, CCVal, Cmp);
SDValue Ops[2] = { Lo, Hi };
return DAG.getMergeValues(Ops, dl);
}
+
/// LowerShiftLeftParts - Lower SHL_PARTS, which returns two
/// i64 values and take a 2 x i64 value to shift plus a shift amount.
SDValue AArch64TargetLowering::LowerShiftLeftParts(SDValue Op,
- SelectionDAG &DAG) const {
+ SelectionDAG &DAG) const {
assert(Op.getNumOperands() == 3 && "Not a double-shift!");
EVT VT = Op.getValueType();
unsigned VTBits = VT.getSizeInBits();
@@ -4427,31 +4438,41 @@ SDValue AArch64TargetLowering::LowerShiftLeftParts(SDValue Op,
SDValue ShOpLo = Op.getOperand(0);
SDValue ShOpHi = Op.getOperand(1);
SDValue ShAmt = Op.getOperand(2);
- SDValue ARMcc;
assert(Op.getOpcode() == ISD::SHL_PARTS);
SDValue RevShAmt = DAG.getNode(ISD::SUB, dl, MVT::i64,
DAG.getConstant(VTBits, dl, MVT::i64), ShAmt);
- SDValue Tmp1 = DAG.getNode(ISD::SRL, dl, VT, ShOpLo, RevShAmt);
+ SDValue LoBitsForHi = DAG.getNode(ISD::SRL, dl, VT, ShOpLo, RevShAmt);
+
+ // Unfortunately, if ShAmt == 0, we just calculated "(SRL ShOpLo, 64)" which
+ // is "undef". We wanted 0, so CSEL it directly.
+ SDValue Cmp = emitComparison(ShAmt, DAG.getConstant(0, dl, MVT::i64),
+ ISD::SETEQ, dl, DAG);
+ SDValue CCVal = DAG.getConstant(AArch64CC::EQ, dl, MVT::i32);
+ LoBitsForHi =
+ DAG.getNode(AArch64ISD::CSEL, dl, VT, DAG.getConstant(0, dl, MVT::i64),
+ LoBitsForHi, CCVal, Cmp);
+
SDValue ExtraShAmt = DAG.getNode(ISD::SUB, dl, MVT::i64, ShAmt,
DAG.getConstant(VTBits, dl, MVT::i64));
- SDValue Tmp2 = DAG.getNode(ISD::SHL, dl, VT, ShOpHi, ShAmt);
- SDValue Tmp3 = DAG.getNode(ISD::SHL, dl, VT, ShOpLo, ExtraShAmt);
+ SDValue HiBitsForHi = DAG.getNode(ISD::SHL, dl, VT, ShOpHi, ShAmt);
+ SDValue HiForNormalShift =
+ DAG.getNode(ISD::OR, dl, VT, LoBitsForHi, HiBitsForHi);
- SDValue FalseVal = DAG.getNode(ISD::OR, dl, VT, Tmp1, Tmp2);
+ SDValue HiForBigShift = DAG.getNode(ISD::SHL, dl, VT, ShOpLo, ExtraShAmt);
- SDValue Cmp = emitComparison(ExtraShAmt, DAG.getConstant(0, dl, MVT::i64),
- ISD::SETGE, dl, DAG);
- SDValue CCVal = DAG.getConstant(AArch64CC::GE, dl, MVT::i32);
- SDValue Hi =
- DAG.getNode(AArch64ISD::CSEL, dl, VT, Tmp3, FalseVal, CCVal, Cmp);
+ Cmp = emitComparison(ExtraShAmt, DAG.getConstant(0, dl, MVT::i64), ISD::SETGE,
+ dl, DAG);
+ CCVal = DAG.getConstant(AArch64CC::GE, dl, MVT::i32);
+ SDValue Hi = DAG.getNode(AArch64ISD::CSEL, dl, VT, HiForBigShift,
+ HiForNormalShift, CCVal, Cmp);
// AArch64 shifts of larger than register sizes are wrapped rather than
// clamped, so we can't just emit "lo << a" if a is too big.
- SDValue TrueValLo = DAG.getConstant(0, dl, VT);
- SDValue FalseValLo = DAG.getNode(ISD::SHL, dl, VT, ShOpLo, ShAmt);
- SDValue Lo =
- DAG.getNode(AArch64ISD::CSEL, dl, VT, TrueValLo, FalseValLo, CCVal, Cmp);
+ SDValue LoForBigShift = DAG.getConstant(0, dl, VT);
+ SDValue LoForNormalShift = DAG.getNode(ISD::SHL, dl, VT, ShOpLo, ShAmt);
+ SDValue Lo = DAG.getNode(AArch64ISD::CSEL, dl, VT, LoForBigShift,
+ LoForNormalShift, CCVal, Cmp);
SDValue Ops[2] = { Lo, Hi };
return DAG.getMergeValues(Ops, dl);
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