diff options
Diffstat (limited to 'llvm/lib/Target/Sparc')
| -rw-r--r-- | llvm/lib/Target/Sparc/Sparc.td | 12 | ||||
| -rw-r--r-- | llvm/lib/Target/Sparc/SparcISelLowering.cpp | 8 |
2 files changed, 17 insertions, 3 deletions
diff --git a/llvm/lib/Target/Sparc/Sparc.td b/llvm/lib/Target/Sparc/Sparc.td index 7137e5f..38b0508 100644 --- a/llvm/lib/Target/Sparc/Sparc.td +++ b/llvm/lib/Target/Sparc/Sparc.td @@ -95,6 +95,9 @@ def FeatureSoftFloat : SubtargetFeature<"soft-float", "UseSoftFloat", "true", def TuneSlowRDPC : SubtargetFeature<"slow-rdpc", "HasSlowRDPC", "true", "rd %pc, %XX is slow", [FeatureV9]>; +def TuneNoPredictor : SubtargetFeature<"no-predictor", "HasNoPredictor", "true", + "Processor has no branch predictor, branches stall execution", []>; + //==== Features added predmoninantly for LEON subtarget support include "LeonFeatures.td" @@ -174,12 +177,15 @@ def : Proc<"ultrasparc3", [FeatureV9, FeatureV8Deprecated, FeatureVIS, FeatureVIS2], [TuneSlowRDPC]>; def : Proc<"niagara", [FeatureV9, FeatureV8Deprecated, FeatureVIS, - FeatureVIS2, FeatureUA2005]>; + FeatureVIS2, FeatureUA2005], + [TuneNoPredictor]>; def : Proc<"niagara2", [FeatureV9, FeatureV8Deprecated, UsePopc, - FeatureVIS, FeatureVIS2, FeatureUA2005]>; + FeatureVIS, FeatureVIS2, FeatureUA2005], + [TuneNoPredictor]>; def : Proc<"niagara3", [FeatureV9, FeatureV8Deprecated, UsePopc, FeatureVIS, FeatureVIS2, FeatureVIS3, - FeatureUA2005, FeatureUA2007]>; + FeatureUA2005, FeatureUA2007], + [TuneNoPredictor]>; def : Proc<"niagara4", [FeatureV9, FeatureV8Deprecated, UsePopc, FeatureVIS, FeatureVIS2, FeatureVIS3, FeatureUA2005, FeatureUA2007, FeatureOSA2011, diff --git a/llvm/lib/Target/Sparc/SparcISelLowering.cpp b/llvm/lib/Target/Sparc/SparcISelLowering.cpp index cbb7db6..ae3c326 100644 --- a/llvm/lib/Target/Sparc/SparcISelLowering.cpp +++ b/llvm/lib/Target/Sparc/SparcISelLowering.cpp @@ -2000,6 +2000,14 @@ SparcTargetLowering::SparcTargetLowering(const TargetMachine &TM, setOperationAction(ISD::INTRINSIC_WO_CHAIN, MVT::Other, Custom); + // Some processors have no branch predictor and have pipelines longer than + // what can be covered by the delay slot. This results in a stall, so mark + // branches to be expensive on those processors. + setJumpIsExpensive(Subtarget->hasNoPredictor()); + // The high cost of branching means that using conditional moves will + // still be profitable even if the condition is predictable. + PredictableSelectIsExpensive = !isJumpExpensive(); + setMinFunctionAlignment(Align(4)); computeRegisterProperties(Subtarget->getRegisterInfo()); |