Commit 007a6a15 authored by Craig Topper's avatar Craig Topper
Browse files

Revert "[X86] Don't exit from foldOffsetIntoAddress if the Offset is 0, but AM.Disp is non-zero." 

Possibly causing build bot failures.
parent 635fbcdd

llvm/lib/Target/X86/X86ISelDAGToDAG.cpp

+20 −11
Original line number Diff line number Diff line
@@ -1409,17 +1409,15 @@ static bool isDispSafeForFrameIndex(int64_t Val) { 


bool X86DAGToDAGISel::foldOffsetIntoAddress(uint64_t Offset,

                                            X86ISelAddressMode &AM) {

  // If the final displacement is 0, we don't need to do any work. We may have

  // already matched a displacement and the caller just added the symbolic

  // displacement with an offset of 0. So recheck everything if Val is non-zero.

  int64_t Val = AM.Disp + Offset;

  if (Val == 0)

  // If there's no offset to fold, we don't need to do any work.

  if (Offset == 0)

    return false;



  // Cannot combine ExternalSymbol displacements with integer offsets.

  if (AM.ES || AM.MCSym)

    return true;



  int64_t Val = AM.Disp + Offset;

  CodeModel::Model M = TM.getCodeModel();

  if (Subtarget->is64Bit()) {

    if (!X86::isOffsetSuitableForCodeModel(Val, M,
@@ -1583,13 +1581,24 @@ bool X86DAGToDAGISel::matchAdd(SDValue &N, X86ISelAddressMode &AM, 
  if (!matchAddressRecursively(N.getOperand(0), AM, Depth+1) &&

      !matchAddressRecursively(Handle.getValue().getOperand(1), AM, Depth+1))

    return false;

  AM = Backup;



  // Don't try commuting operands if the address is in the form of

  // sym+disp(%rip). foldOffsetIntoAddress() currently does not know there is a

  // symbolic displacement and would fold disp. If disp is just a bit smaller

  // than 2**31, it can easily cause a relocation overflow.

  bool NoCommutate = false;

  if (AM.isRIPRelative() && AM.hasSymbolicDisplacement())

    if (ConstantSDNode *Cst =

            dyn_cast<ConstantSDNode>(Handle.getValue().getOperand(1)))

      NoCommutate = Cst->getSExtValue() != 0;



  AM = Backup;

  if (!NoCommutate) {

    // Try again after commutating the operands.

  if (!matchAddressRecursively(Handle.getValue().getOperand(1), AM,

                               Depth + 1) &&

    if (!matchAddressRecursively(Handle.getValue().getOperand(1), AM, Depth + 1) &&

        !matchAddressRecursively(Handle.getValue().getOperand(0), AM, Depth + 1))

      return false;

  }

  AM = Backup;



  // If we couldn't fold both operands into the address at the same time,