diff options
Diffstat (limited to 'lib/Target/ARM/ARMISelLowering.cpp')
| -rw-r--r-- | lib/Target/ARM/ARMISelLowering.cpp | 24 |
1 files changed, 12 insertions, 12 deletions
diff --git a/lib/Target/ARM/ARMISelLowering.cpp b/lib/Target/ARM/ARMISelLowering.cpp index 6398f1bf0c..56adcf2b37 100644 --- a/lib/Target/ARM/ARMISelLowering.cpp +++ b/lib/Target/ARM/ARMISelLowering.cpp @@ -412,12 +412,10 @@ ARMTargetLowering::ARMTargetLowering(TargetMachine &TM) // doesn't yet know how to not do that for SjLj. setExceptionSelectorRegister(ARM::R0); setOperationAction(ISD::DYNAMIC_STACKALLOC, MVT::i32, Expand); - // Handle atomics directly for ARMv[67] (except for Thumb1), otherwise - // use the default expansion. - bool canHandleAtomics = - (Subtarget->hasV7Ops() || - (Subtarget->hasV6Ops() && !Subtarget->isThumb1Only())); - if (canHandleAtomics) { + // ARMv6 Thumb1 (except for CPUs that support dmb / dsb) and earlier use + // the default expansion. + if (Subtarget->hasDataBarrier() || + (Subtarget->hasV6Ops() && !Subtarget->isThumb1Only())) { // membarrier needs custom lowering; the rest are legal and handled // normally. setOperationAction(ISD::MEMBARRIER, MVT::Other, Custom); @@ -1992,17 +1990,19 @@ static SDValue LowerMEMBARRIER(SDValue Op, SelectionDAG &DAG, DebugLoc dl = Op.getDebugLoc(); SDValue Op5 = Op.getOperand(5); unsigned isDeviceBarrier = cast<ConstantSDNode>(Op5)->getZExtValue(); - // v6 and v7 can both handle barriers directly, but need handled a bit - // differently. Thumb1 and pre-v6 ARM mode use a libcall instead and should + // Some subtargets which have dmb and dsb instructions can handle barriers + // directly. Some ARMv6 cpus can support them with the help of mcr + // instruction. Thumb1 and pre-v6 ARM mode use a libcall instead and should // never get here. unsigned Opc = isDeviceBarrier ? ARMISD::SYNCBARRIER : ARMISD::MEMBARRIER; - if (Subtarget->hasV7Ops()) + if (Subtarget->hasDataBarrier()) return DAG.getNode(Opc, dl, MVT::Other, Op.getOperand(0)); - else if (Subtarget->hasV6Ops() && !Subtarget->isThumb1Only()) + else { + assert(Subtarget->hasV6Ops() && !Subtarget->isThumb1Only() && + "Unexpected ISD::MEMBARRIER encountered. Should be libcall!"); return DAG.getNode(Opc, dl, MVT::Other, Op.getOperand(0), DAG.getConstant(0, MVT::i32)); - assert(0 && "Unexpected ISD::MEMBARRIER encountered. Should be libcall!"); - return SDValue(); + } } static SDValue LowerVASTART(SDValue Op, SelectionDAG &DAG) { |