Commit 45acbd03 authored by Bob Wilson's avatar Bob Wilson
Browse files

Fix a compiler crash where a Glue value had multiple uses. Radar 9049552. 

llvm-svn: 127198
parent 70bd3635

llvm/lib/Target/ARM/ARMISelLowering.cpp

+22 −1
Original line number Diff line number Diff line
@@ -2527,6 +2527,27 @@ ARMTargetLowering::getVFPCmp(SDValue LHS, SDValue RHS, SelectionDAG &DAG, 
  return DAG.getNode(ARMISD::FMSTAT, dl, MVT::Glue, Cmp);

}



/// duplicateCmp - Glue values can have only one use, so this function

/// duplicates a comparison node.

SDValue

ARMTargetLowering::duplicateCmp(SDValue Cmp, SelectionDAG &DAG) const {

  unsigned Opc = Cmp.getOpcode();

  DebugLoc DL = Cmp.getDebugLoc();

  if (Opc == ARMISD::CMP || Opc == ARMISD::CMPZ)

    return DAG.getNode(Opc, DL, MVT::Glue, Cmp.getOperand(0),Cmp.getOperand(1));



  assert(Opc == ARMISD::FMSTAT && "unexpected comparison operation");

  Cmp = Cmp.getOperand(0);

  Opc = Cmp.getOpcode();

  if (Opc == ARMISD::CMPFP)

    Cmp = DAG.getNode(Opc, DL, MVT::Glue, Cmp.getOperand(0),Cmp.getOperand(1));

  else {

    assert(Opc == ARMISD::CMPFPw0 && "unexpected operand of FMSTAT");

    Cmp = DAG.getNode(Opc, DL, MVT::Glue, Cmp.getOperand(0));

  }

  return DAG.getNode(ARMISD::FMSTAT, DL, MVT::Glue, Cmp);

}



SDValue ARMTargetLowering::LowerSELECT(SDValue Op, SelectionDAG &DAG) const {

  SDValue Cond = Op.getOperand(0);

  SDValue SelectTrue = Op.getOperand(1);
@@ -2562,7 +2583,7 @@ SDValue ARMTargetLowering::LowerSELECT(SDValue Op, SelectionDAG &DAG) const { 
        EVT VT = Cond.getValueType();

        SDValue ARMcc = Cond.getOperand(2);

        SDValue CCR = Cond.getOperand(3);

        SDValue Cmp = Cond.getOperand(4);

        SDValue Cmp = duplicateCmp(Cond.getOperand(4), DAG);

        return DAG.getNode(ARMISD::CMOV, dl, VT, True, False, ARMcc, CCR, Cmp);

      }

    }

llvm/lib/Target/ARM/ARMISelLowering.h

+1 −0
Original line number Diff line number Diff line
@@ -459,6 +459,7 @@ namespace llvm { 
                      SDValue &ARMcc, SelectionDAG &DAG, DebugLoc dl) const;

    SDValue getVFPCmp(SDValue LHS, SDValue RHS,

                      SelectionDAG &DAG, DebugLoc dl) const;

    SDValue duplicateCmp(SDValue Cmp, SelectionDAG &DAG) const;



    SDValue OptimizeVFPBrcond(SDValue Op, SelectionDAG &DAG) const;

llvm/test/CodeGen/ARM/select.ll

+23 −0
Original line number Diff line number Diff line
@@ -90,3 +90,26 @@ define arm_apcscc float @f8(i32 %a) nounwind { 
  %tmp1 = select i1 %tmp, float 0x3FF3BE76C0000000, float 0x40030E9A20000000

  ret float %tmp1

}



; <rdar://problem/9049552>

; Glue values can only have a single use, but the following test exposed a

; case where a SELECT was lowered with 2 uses of a comparison, causing the

; scheduler to assert.

; CHECK-VFP: f9:



declare i8* @objc_msgSend(i8*, i8*, ...)

define void @f9() optsize {

entry:

  %cmp = icmp eq i8* undef, inttoptr (i32 4 to i8*)

  %conv191 = select i1 %cmp, float -3.000000e+00, float 0.000000e+00

  %conv195 = select i1 %cmp, double -1.000000e+00, double 0.000000e+00

  %add = fadd double %conv195, 1.100000e+01

  %conv196 = fptrunc double %add to float

  %add201 = fadd float undef, %conv191

  %tmp484 = bitcast float %conv196 to i32

  %tmp478 = bitcast float %add201 to i32

  %tmp490 = insertvalue [2 x i32] undef, i32 %tmp484, 0

  %tmp493 = insertvalue [2 x i32] %tmp490, i32 %tmp478, 1

  call void bitcast (i8* (i8*, i8*, ...)* @objc_msgSend to void (i8*, i8*, [2 x i32], i32, float)*)(i8* undef, i8* undef, [2 x i32] %tmp493, i32 0, float 1.000000e+00) optsize

  ret void

}