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author | Stephen Hines <srhines@google.com> | 2014-04-23 16:57:46 -0700 |
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committer | Stephen Hines <srhines@google.com> | 2014-04-24 15:53:16 -0700 |
commit | 36b56886974eae4f9c5ebc96befd3e7bfe5de338 (patch) | |
tree | e6cfb69fbbd937f450eeb83bfb83b9da3b01275a /lib/Target/PowerPC/PPCHazardRecognizers.cpp | |
parent | 69a8640022b04415ae9fac62f8ab090601d8f889 (diff) | |
download | external_llvm-36b56886974eae4f9c5ebc96befd3e7bfe5de338.zip external_llvm-36b56886974eae4f9c5ebc96befd3e7bfe5de338.tar.gz external_llvm-36b56886974eae4f9c5ebc96befd3e7bfe5de338.tar.bz2 |
Update to LLVM 3.5a.
Change-Id: Ifadecab779f128e62e430c2b4f6ddd84953ed617
Diffstat (limited to 'lib/Target/PowerPC/PPCHazardRecognizers.cpp')
-rw-r--r-- | lib/Target/PowerPC/PPCHazardRecognizers.cpp | 208 |
1 files changed, 197 insertions, 11 deletions
diff --git a/lib/Target/PowerPC/PPCHazardRecognizers.cpp b/lib/Target/PowerPC/PPCHazardRecognizers.cpp index 0df50e1..37c85b3 100644 --- a/lib/Target/PowerPC/PPCHazardRecognizers.cpp +++ b/lib/Target/PowerPC/PPCHazardRecognizers.cpp @@ -15,34 +15,220 @@ #include "PPCHazardRecognizers.h" #include "PPC.h" #include "PPCInstrInfo.h" +#include "PPCTargetMachine.h" #include "llvm/CodeGen/ScheduleDAG.h" #include "llvm/Support/Debug.h" #include "llvm/Support/ErrorHandling.h" #include "llvm/Support/raw_ostream.h" using namespace llvm; -//===----------------------------------------------------------------------===// -// PowerPC Scoreboard Hazard Recognizer -void PPCScoreboardHazardRecognizer::EmitInstruction(SUnit *SU) { +bool PPCDispatchGroupSBHazardRecognizer::isLoadAfterStore(SUnit *SU) { + // FIXME: Move this. + if (isBCTRAfterSet(SU)) + return true; + const MCInstrDesc *MCID = DAG->getInstrDesc(SU); if (!MCID) - // This is a PPC pseudo-instruction. - return; + return false; + + if (!MCID->mayLoad()) + return false; + + // SU is a load; for any predecessors in this dispatch group, that are stores, + // and with which we have an ordering dependency, return true. + for (unsigned i = 0, ie = (unsigned) SU->Preds.size(); i != ie; ++i) { + const MCInstrDesc *PredMCID = DAG->getInstrDesc(SU->Preds[i].getSUnit()); + if (!PredMCID || !PredMCID->mayStore()) + continue; + + if (!SU->Preds[i].isNormalMemory() && !SU->Preds[i].isBarrier()) + continue; + + for (unsigned j = 0, je = CurGroup.size(); j != je; ++j) + if (SU->Preds[i].getSUnit() == CurGroup[j]) + return true; + } + + return false; +} + +bool PPCDispatchGroupSBHazardRecognizer::isBCTRAfterSet(SUnit *SU) { + const MCInstrDesc *MCID = DAG->getInstrDesc(SU); + if (!MCID) + return false; + + if (!MCID->isBranch()) + return false; + + // SU is a branch; for any predecessors in this dispatch group, with which we + // have a data dependence and set the counter register, return true. + for (unsigned i = 0, ie = (unsigned) SU->Preds.size(); i != ie; ++i) { + const MCInstrDesc *PredMCID = DAG->getInstrDesc(SU->Preds[i].getSUnit()); + if (!PredMCID || PredMCID->getSchedClass() != PPC::Sched::IIC_SprMTSPR) + continue; + + if (SU->Preds[i].isCtrl()) + continue; + + for (unsigned j = 0, je = CurGroup.size(); j != je; ++j) + if (SU->Preds[i].getSUnit() == CurGroup[j]) + return true; + } + + return false; +} + +// FIXME: Remove this when we don't need this: +namespace llvm { namespace PPC { extern int getNonRecordFormOpcode(uint16_t); } } + +// FIXME: A lot of code in PPCDispatchGroupSBHazardRecognizer is P7 specific. + +bool PPCDispatchGroupSBHazardRecognizer::mustComeFirst(const MCInstrDesc *MCID, + unsigned &NSlots) { + // FIXME: Indirectly, this information is contained in the itinerary, and + // we should derive it from there instead of separately specifying it + // here. + unsigned IIC = MCID->getSchedClass(); + switch (IIC) { + default: + NSlots = 1; + break; + case PPC::Sched::IIC_IntDivW: + case PPC::Sched::IIC_IntDivD: + case PPC::Sched::IIC_LdStLoadUpd: + case PPC::Sched::IIC_LdStLDU: + case PPC::Sched::IIC_LdStLFDU: + case PPC::Sched::IIC_LdStLFDUX: + case PPC::Sched::IIC_LdStLHA: + case PPC::Sched::IIC_LdStLHAU: + case PPC::Sched::IIC_LdStLWA: + case PPC::Sched::IIC_LdStSTDU: + case PPC::Sched::IIC_LdStSTFDU: + NSlots = 2; + break; + case PPC::Sched::IIC_LdStLoadUpdX: + case PPC::Sched::IIC_LdStLDUX: + case PPC::Sched::IIC_LdStLHAUX: + case PPC::Sched::IIC_LdStLWARX: + case PPC::Sched::IIC_LdStLDARX: + case PPC::Sched::IIC_LdStSTDUX: + case PPC::Sched::IIC_LdStSTDCX: + case PPC::Sched::IIC_LdStSTWCX: + case PPC::Sched::IIC_BrMCRX: // mtcr + // FIXME: Add sync/isync (here and in the itinerary). + NSlots = 4; + break; + } - ScoreboardHazardRecognizer::EmitInstruction(SU); + // FIXME: record-form instructions need a different itinerary class. + if (NSlots == 1 && PPC::getNonRecordFormOpcode(MCID->getOpcode()) != -1) + NSlots = 2; + + switch (IIC) { + default: + // All multi-slot instructions must come first. + return NSlots > 1; + case PPC::Sched::IIC_BrCR: // cr logicals + case PPC::Sched::IIC_SprMFCR: + case PPC::Sched::IIC_SprMFCRF: + case PPC::Sched::IIC_SprMTSPR: + return true; + } } ScheduleHazardRecognizer::HazardType -PPCScoreboardHazardRecognizer::getHazardType(SUnit *SU, int Stalls) { +PPCDispatchGroupSBHazardRecognizer::getHazardType(SUnit *SU, int Stalls) { + if (Stalls == 0 && isLoadAfterStore(SU)) + return NoopHazard; + return ScoreboardHazardRecognizer::getHazardType(SU, Stalls); } -void PPCScoreboardHazardRecognizer::AdvanceCycle() { - ScoreboardHazardRecognizer::AdvanceCycle(); +bool PPCDispatchGroupSBHazardRecognizer::ShouldPreferAnother(SUnit *SU) { + const MCInstrDesc *MCID = DAG->getInstrDesc(SU); + unsigned NSlots; + if (MCID && mustComeFirst(MCID, NSlots) && CurSlots) + return true; + + return ScoreboardHazardRecognizer::ShouldPreferAnother(SU); +} + +unsigned PPCDispatchGroupSBHazardRecognizer::PreEmitNoops(SUnit *SU) { + // We only need to fill out a maximum of 5 slots here: The 6th slot could + // only be a second branch, and otherwise the next instruction will start a + // new group. + if (isLoadAfterStore(SU) && CurSlots < 6) { + unsigned Directive = + DAG->TM.getSubtarget<PPCSubtarget>().getDarwinDirective(); + // If we're using a special group-terminating nop, then we need only one. + if (Directive == PPC::DIR_PWR6 || Directive == PPC::DIR_PWR7) + return 1; + + return 5 - CurSlots; + } + + return ScoreboardHazardRecognizer::PreEmitNoops(SU); +} + +void PPCDispatchGroupSBHazardRecognizer::EmitInstruction(SUnit *SU) { + const MCInstrDesc *MCID = DAG->getInstrDesc(SU); + if (MCID) { + if (CurSlots == 5 || (MCID->isBranch() && CurBranches == 1)) { + CurGroup.clear(); + CurSlots = CurBranches = 0; + } else { + DEBUG(dbgs() << "**** Adding to dispatch group: SU(" << + SU->NodeNum << "): "); + DEBUG(DAG->dumpNode(SU)); + + unsigned NSlots; + bool MustBeFirst = mustComeFirst(MCID, NSlots); + + // If this instruction must come first, but does not, then it starts a + // new group. + if (MustBeFirst && CurSlots) { + CurSlots = CurBranches = 0; + CurGroup.clear(); + } + + CurSlots += NSlots; + CurGroup.push_back(SU); + + if (MCID->isBranch()) + ++CurBranches; + } + } + + return ScoreboardHazardRecognizer::EmitInstruction(SU); +} + +void PPCDispatchGroupSBHazardRecognizer::AdvanceCycle() { + return ScoreboardHazardRecognizer::AdvanceCycle(); +} + +void PPCDispatchGroupSBHazardRecognizer::RecedeCycle() { + llvm_unreachable("Bottom-up scheduling not supported"); } -void PPCScoreboardHazardRecognizer::Reset() { - ScoreboardHazardRecognizer::Reset(); +void PPCDispatchGroupSBHazardRecognizer::Reset() { + CurGroup.clear(); + CurSlots = CurBranches = 0; + return ScoreboardHazardRecognizer::Reset(); +} + +void PPCDispatchGroupSBHazardRecognizer::EmitNoop() { + unsigned Directive = + DAG->TM.getSubtarget<PPCSubtarget>().getDarwinDirective(); + // If the group has now filled all of its slots, or if we're using a special + // group-terminating nop, the group is complete. + if (Directive == PPC::DIR_PWR6 || Directive == PPC::DIR_PWR7 || + CurSlots == 6) { + CurGroup.clear(); + CurSlots = CurBranches = 0; + } else { + CurGroup.push_back(0); + ++CurSlots; + } } //===----------------------------------------------------------------------===// |