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-rw-r--r--contrib/llvm/lib/Target/R600/R600EmitClauseMarkers.cpp325
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diff --git a/contrib/llvm/lib/Target/R600/R600EmitClauseMarkers.cpp b/contrib/llvm/lib/Target/R600/R600EmitClauseMarkers.cpp
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+++ b/contrib/llvm/lib/Target/R600/R600EmitClauseMarkers.cpp
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+//===-- R600EmitClauseMarkers.cpp - Emit CF_ALU ---------------------------===//
+//
+// The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+/// \file
+/// Add CF_ALU. R600 Alu instructions are grouped in clause which can hold
+/// 128 Alu instructions ; these instructions can access up to 4 prefetched
+/// 4 lines of 16 registers from constant buffers. Such ALU clauses are
+/// initiated by CF_ALU instructions.
+//===----------------------------------------------------------------------===//
+
+#include "AMDGPU.h"
+#include "R600Defines.h"
+#include "R600InstrInfo.h"
+#include "R600MachineFunctionInfo.h"
+#include "R600RegisterInfo.h"
+#include "llvm/CodeGen/MachineFunctionPass.h"
+#include "llvm/CodeGen/MachineInstrBuilder.h"
+#include "llvm/CodeGen/MachineRegisterInfo.h"
+
+using namespace llvm;
+
+namespace {
+
+class R600EmitClauseMarkersPass : public MachineFunctionPass {
+
+private:
+ static char ID;
+ const R600InstrInfo *TII;
+ int Address;
+
+ unsigned OccupiedDwords(MachineInstr *MI) const {
+ switch (MI->getOpcode()) {
+ case AMDGPU::INTERP_PAIR_XY:
+ case AMDGPU::INTERP_PAIR_ZW:
+ case AMDGPU::INTERP_VEC_LOAD:
+ case AMDGPU::DOT_4:
+ return 4;
+ case AMDGPU::KILL:
+ return 0;
+ default:
+ break;
+ }
+
+ // These will be expanded to two ALU instructions in the
+ // ExpandSpecialInstructions pass.
+ if (TII->isLDSRetInstr(MI->getOpcode()))
+ return 2;
+
+ if(TII->isVector(*MI) ||
+ TII->isCubeOp(MI->getOpcode()) ||
+ TII->isReductionOp(MI->getOpcode()))
+ return 4;
+
+ unsigned NumLiteral = 0;
+ for (MachineInstr::mop_iterator It = MI->operands_begin(),
+ E = MI->operands_end(); It != E; ++It) {
+ MachineOperand &MO = *It;
+ if (MO.isReg() && MO.getReg() == AMDGPU::ALU_LITERAL_X)
+ ++NumLiteral;
+ }
+ return 1 + NumLiteral;
+ }
+
+ bool isALU(const MachineInstr *MI) const {
+ if (TII->isALUInstr(MI->getOpcode()))
+ return true;
+ if (TII->isVector(*MI) || TII->isCubeOp(MI->getOpcode()))
+ return true;
+ switch (MI->getOpcode()) {
+ case AMDGPU::PRED_X:
+ case AMDGPU::INTERP_PAIR_XY:
+ case AMDGPU::INTERP_PAIR_ZW:
+ case AMDGPU::INTERP_VEC_LOAD:
+ case AMDGPU::COPY:
+ case AMDGPU::DOT_4:
+ return true;
+ default:
+ return false;
+ }
+ }
+
+ bool IsTrivialInst(MachineInstr *MI) const {
+ switch (MI->getOpcode()) {
+ case AMDGPU::KILL:
+ case AMDGPU::RETURN:
+ case AMDGPU::IMPLICIT_DEF:
+ return true;
+ default:
+ return false;
+ }
+ }
+
+ std::pair<unsigned, unsigned> getAccessedBankLine(unsigned Sel) const {
+ // Sel is (512 + (kc_bank << 12) + ConstIndex) << 2
+ // (See also R600ISelLowering.cpp)
+ // ConstIndex value is in [0, 4095];
+ return std::pair<unsigned, unsigned>(
+ ((Sel >> 2) - 512) >> 12, // KC_BANK
+ // Line Number of ConstIndex
+ // A line contains 16 constant registers however KCX bank can lock
+ // two line at the same time ; thus we want to get an even line number.
+ // Line number can be retrieved with (>>4), using (>>5) <<1 generates
+ // an even number.
+ ((((Sel >> 2) - 512) & 4095) >> 5) << 1);
+ }
+
+ bool SubstituteKCacheBank(MachineInstr *MI,
+ std::vector<std::pair<unsigned, unsigned> > &CachedConsts,
+ bool UpdateInstr = true) const {
+ std::vector<std::pair<unsigned, unsigned> > UsedKCache;
+
+ if (!TII->isALUInstr(MI->getOpcode()) && MI->getOpcode() != AMDGPU::DOT_4)
+ return true;
+
+ const SmallVectorImpl<std::pair<MachineOperand *, int64_t> > &Consts =
+ TII->getSrcs(MI);
+ assert((TII->isALUInstr(MI->getOpcode()) ||
+ MI->getOpcode() == AMDGPU::DOT_4) && "Can't assign Const");
+ for (unsigned i = 0, n = Consts.size(); i < n; ++i) {
+ if (Consts[i].first->getReg() != AMDGPU::ALU_CONST)
+ continue;
+ unsigned Sel = Consts[i].second;
+ unsigned Chan = Sel & 3, Index = ((Sel >> 2) - 512) & 31;
+ unsigned KCacheIndex = Index * 4 + Chan;
+ const std::pair<unsigned, unsigned> &BankLine = getAccessedBankLine(Sel);
+ if (CachedConsts.empty()) {
+ CachedConsts.push_back(BankLine);
+ UsedKCache.push_back(std::pair<unsigned, unsigned>(0, KCacheIndex));
+ continue;
+ }
+ if (CachedConsts[0] == BankLine) {
+ UsedKCache.push_back(std::pair<unsigned, unsigned>(0, KCacheIndex));
+ continue;
+ }
+ if (CachedConsts.size() == 1) {
+ CachedConsts.push_back(BankLine);
+ UsedKCache.push_back(std::pair<unsigned, unsigned>(1, KCacheIndex));
+ continue;
+ }
+ if (CachedConsts[1] == BankLine) {
+ UsedKCache.push_back(std::pair<unsigned, unsigned>(1, KCacheIndex));
+ continue;
+ }
+ return false;
+ }
+
+ if (!UpdateInstr)
+ return true;
+
+ for (unsigned i = 0, j = 0, n = Consts.size(); i < n; ++i) {
+ if (Consts[i].first->getReg() != AMDGPU::ALU_CONST)
+ continue;
+ switch(UsedKCache[j].first) {
+ case 0:
+ Consts[i].first->setReg(
+ AMDGPU::R600_KC0RegClass.getRegister(UsedKCache[j].second));
+ break;
+ case 1:
+ Consts[i].first->setReg(
+ AMDGPU::R600_KC1RegClass.getRegister(UsedKCache[j].second));
+ break;
+ default:
+ llvm_unreachable("Wrong Cache Line");
+ }
+ j++;
+ }
+ return true;
+ }
+
+ bool canClauseLocalKillFitInClause(
+ unsigned AluInstCount,
+ std::vector<std::pair<unsigned, unsigned> > KCacheBanks,
+ MachineBasicBlock::iterator Def,
+ MachineBasicBlock::iterator BBEnd) {
+ const R600RegisterInfo &TRI = TII->getRegisterInfo();
+ for (MachineInstr::const_mop_iterator
+ MOI = Def->operands_begin(),
+ MOE = Def->operands_end(); MOI != MOE; ++MOI) {
+ if (!MOI->isReg() || !MOI->isDef() ||
+ TRI.isPhysRegLiveAcrossClauses(MOI->getReg()))
+ continue;
+
+ // Def defines a clause local register, so check that its use will fit
+ // in the clause.
+ unsigned LastUseCount = 0;
+ for (MachineBasicBlock::iterator UseI = Def; UseI != BBEnd; ++UseI) {
+ AluInstCount += OccupiedDwords(UseI);
+ // Make sure we won't need to end the clause due to KCache limitations.
+ if (!SubstituteKCacheBank(UseI, KCacheBanks, false))
+ return false;
+
+ // We have reached the maximum instruction limit before finding the
+ // use that kills this register, so we cannot use this def in the
+ // current clause.
+ if (AluInstCount >= TII->getMaxAlusPerClause())
+ return false;
+
+ // Register kill flags have been cleared by the time we get to this
+ // pass, but it is safe to assume that all uses of this register
+ // occur in the same basic block as its definition, because
+ // it is illegal for the scheduler to schedule them in
+ // different blocks.
+ if (UseI->findRegisterUseOperandIdx(MOI->getReg()))
+ LastUseCount = AluInstCount;
+
+ if (UseI != Def && UseI->findRegisterDefOperandIdx(MOI->getReg()) != -1)
+ break;
+ }
+ if (LastUseCount)
+ return LastUseCount <= TII->getMaxAlusPerClause();
+ llvm_unreachable("Clause local register live at end of clause.");
+ }
+ return true;
+ }
+
+ MachineBasicBlock::iterator
+ MakeALUClause(MachineBasicBlock &MBB, MachineBasicBlock::iterator I) {
+ MachineBasicBlock::iterator ClauseHead = I;
+ std::vector<std::pair<unsigned, unsigned> > KCacheBanks;
+ bool PushBeforeModifier = false;
+ unsigned AluInstCount = 0;
+ for (MachineBasicBlock::iterator E = MBB.end(); I != E; ++I) {
+ if (IsTrivialInst(I))
+ continue;
+ if (!isALU(I))
+ break;
+ if (AluInstCount > TII->getMaxAlusPerClause())
+ break;
+ if (I->getOpcode() == AMDGPU::PRED_X) {
+ // We put PRED_X in its own clause to ensure that ifcvt won't create
+ // clauses with more than 128 insts.
+ // IfCvt is indeed checking that "then" and "else" branches of an if
+ // statement have less than ~60 insts thus converted clauses can't be
+ // bigger than ~121 insts (predicate setter needs to be in the same
+ // clause as predicated alus).
+ if (AluInstCount > 0)
+ break;
+ if (TII->getFlagOp(I).getImm() & MO_FLAG_PUSH)
+ PushBeforeModifier = true;
+ AluInstCount ++;
+ continue;
+ }
+ // XXX: GROUP_BARRIER instructions cannot be in the same ALU clause as:
+ //
+ // * KILL or INTERP instructions
+ // * Any instruction that sets UPDATE_EXEC_MASK or UPDATE_PRED bits
+ // * Uses waterfalling (i.e. INDEX_MODE = AR.X)
+ //
+ // XXX: These checks have not been implemented yet.
+ if (TII->mustBeLastInClause(I->getOpcode())) {
+ I++;
+ break;
+ }
+
+ // If this instruction defines a clause local register, make sure
+ // its use can fit in this clause.
+ if (!canClauseLocalKillFitInClause(AluInstCount, KCacheBanks, I, E))
+ break;
+
+ if (!SubstituteKCacheBank(I, KCacheBanks))
+ break;
+ AluInstCount += OccupiedDwords(I);
+ }
+ unsigned Opcode = PushBeforeModifier ?
+ AMDGPU::CF_ALU_PUSH_BEFORE : AMDGPU::CF_ALU;
+ BuildMI(MBB, ClauseHead, MBB.findDebugLoc(ClauseHead), TII->get(Opcode))
+ // We don't use the ADDR field until R600ControlFlowFinalizer pass, where
+ // it is safe to assume it is 0. However if we always put 0 here, the ifcvt
+ // pass may assume that identical ALU clause starter at the beginning of a
+ // true and false branch can be factorized which is not the case.
+ .addImm(Address++) // ADDR
+ .addImm(KCacheBanks.empty()?0:KCacheBanks[0].first) // KB0
+ .addImm((KCacheBanks.size() < 2)?0:KCacheBanks[1].first) // KB1
+ .addImm(KCacheBanks.empty()?0:2) // KM0
+ .addImm((KCacheBanks.size() < 2)?0:2) // KM1
+ .addImm(KCacheBanks.empty()?0:KCacheBanks[0].second) // KLINE0
+ .addImm((KCacheBanks.size() < 2)?0:KCacheBanks[1].second) // KLINE1
+ .addImm(AluInstCount) // COUNT
+ .addImm(1); // Enabled
+ return I;
+ }
+
+public:
+ R600EmitClauseMarkersPass(TargetMachine &tm) : MachineFunctionPass(ID),
+ TII(0), Address(0) { }
+
+ virtual bool runOnMachineFunction(MachineFunction &MF) {
+ TII = static_cast<const R600InstrInfo *>(MF.getTarget().getInstrInfo());
+
+ for (MachineFunction::iterator BB = MF.begin(), BB_E = MF.end();
+ BB != BB_E; ++BB) {
+ MachineBasicBlock &MBB = *BB;
+ MachineBasicBlock::iterator I = MBB.begin();
+ if (I->getOpcode() == AMDGPU::CF_ALU)
+ continue; // BB was already parsed
+ for (MachineBasicBlock::iterator E = MBB.end(); I != E;) {
+ if (isALU(I))
+ I = MakeALUClause(MBB, I);
+ else
+ ++I;
+ }
+ }
+ return false;
+ }
+
+ const char *getPassName() const {
+ return "R600 Emit Clause Markers Pass";
+ }
+};
+
+char R600EmitClauseMarkersPass::ID = 0;
+
+} // end anonymous namespace
+
+
+llvm::FunctionPass *llvm::createR600EmitClauseMarkers(TargetMachine &TM) {
+ return new R600EmitClauseMarkersPass(TM);
+}
+