diff options
author | Dimitry Andric <dim@FreeBSD.org> | 2019-12-20 19:53:05 +0000 |
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committer | Dimitry Andric <dim@FreeBSD.org> | 2019-12-20 19:53:05 +0000 |
commit | 0b57cec536236d46e3dba9bd041533462f33dbb7 (patch) | |
tree | 56229dbdbbf76d18580f72f789003db17246c8d9 /contrib/llvm-project/llvm/lib/Target/PowerPC/PPCSubtarget.cpp | |
parent | 718ef55ec7785aae63f98f8ca05dc07ed399c16d (diff) |
Notes
Diffstat (limited to 'contrib/llvm-project/llvm/lib/Target/PowerPC/PPCSubtarget.cpp')
-rw-r--r-- | contrib/llvm-project/llvm/lib/Target/PowerPC/PPCSubtarget.cpp | 247 |
1 files changed, 247 insertions, 0 deletions
diff --git a/contrib/llvm-project/llvm/lib/Target/PowerPC/PPCSubtarget.cpp b/contrib/llvm-project/llvm/lib/Target/PowerPC/PPCSubtarget.cpp new file mode 100644 index 000000000000..6239decf1539 --- /dev/null +++ b/contrib/llvm-project/llvm/lib/Target/PowerPC/PPCSubtarget.cpp @@ -0,0 +1,247 @@ +//===-- PowerPCSubtarget.cpp - PPC Subtarget Information ------------------===// +// +// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. +// See https://llvm.org/LICENSE.txt for license information. +// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception +// +//===----------------------------------------------------------------------===// +// +// This file implements the PPC specific subclass of TargetSubtargetInfo. +// +//===----------------------------------------------------------------------===// + +#include "PPCSubtarget.h" +#include "PPC.h" +#include "PPCRegisterInfo.h" +#include "PPCTargetMachine.h" +#include "llvm/CodeGen/MachineFunction.h" +#include "llvm/CodeGen/MachineScheduler.h" +#include "llvm/IR/Attributes.h" +#include "llvm/IR/Function.h" +#include "llvm/IR/GlobalValue.h" +#include "llvm/Support/CommandLine.h" +#include "llvm/Support/TargetRegistry.h" +#include "llvm/Target/TargetMachine.h" +#include <cstdlib> + +using namespace llvm; + +#define DEBUG_TYPE "ppc-subtarget" + +#define GET_SUBTARGETINFO_TARGET_DESC +#define GET_SUBTARGETINFO_CTOR +#include "PPCGenSubtargetInfo.inc" + +static cl::opt<bool> UseSubRegLiveness("ppc-track-subreg-liveness", +cl::desc("Enable subregister liveness tracking for PPC"), cl::Hidden); + +static cl::opt<bool> QPXStackUnaligned("qpx-stack-unaligned", + cl::desc("Even when QPX is enabled the stack is not 32-byte aligned"), + cl::Hidden); + +static cl::opt<bool> + EnableMachinePipeliner("ppc-enable-pipeliner", + cl::desc("Enable Machine Pipeliner for PPC"), + cl::init(false), cl::Hidden); + +PPCSubtarget &PPCSubtarget::initializeSubtargetDependencies(StringRef CPU, + StringRef FS) { + initializeEnvironment(); + initSubtargetFeatures(CPU, FS); + return *this; +} + +PPCSubtarget::PPCSubtarget(const Triple &TT, const std::string &CPU, + const std::string &FS, const PPCTargetMachine &TM) + : PPCGenSubtargetInfo(TT, CPU, FS), TargetTriple(TT), + IsPPC64(TargetTriple.getArch() == Triple::ppc64 || + TargetTriple.getArch() == Triple::ppc64le), + TM(TM), FrameLowering(initializeSubtargetDependencies(CPU, FS)), + InstrInfo(*this), TLInfo(TM, *this) {} + +void PPCSubtarget::initializeEnvironment() { + StackAlignment = 16; + DarwinDirective = PPC::DIR_NONE; + HasMFOCRF = false; + Has64BitSupport = false; + Use64BitRegs = false; + UseCRBits = false; + HasHardFloat = false; + HasAltivec = false; + HasSPE = false; + HasFPU = false; + HasQPX = false; + HasVSX = false; + NeedsTwoConstNR = false; + HasP8Vector = false; + HasP8Altivec = false; + HasP8Crypto = false; + HasP9Vector = false; + HasP9Altivec = false; + HasFCPSGN = false; + HasFSQRT = false; + HasFRE = false; + HasFRES = false; + HasFRSQRTE = false; + HasFRSQRTES = false; + HasRecipPrec = false; + HasSTFIWX = false; + HasLFIWAX = false; + HasFPRND = false; + HasFPCVT = false; + HasISEL = false; + HasBPERMD = false; + HasExtDiv = false; + HasCMPB = false; + HasLDBRX = false; + IsBookE = false; + HasOnlyMSYNC = false; + IsPPC4xx = false; + IsPPC6xx = false; + IsE500 = false; + FeatureMFTB = false; + DeprecatedDST = false; + HasLazyResolverStubs = false; + HasICBT = false; + HasInvariantFunctionDescriptors = false; + HasPartwordAtomics = false; + HasDirectMove = false; + IsQPXStackUnaligned = false; + HasHTM = false; + HasFloat128 = false; + IsISA3_0 = false; + UseLongCalls = false; + SecurePlt = false; + VectorsUseTwoUnits = false; + UsePPCPreRASchedStrategy = false; + UsePPCPostRASchedStrategy = false; + + HasPOPCNTD = POPCNTD_Unavailable; +} + +void PPCSubtarget::initSubtargetFeatures(StringRef CPU, StringRef FS) { + // Determine default and user specified characteristics + std::string CPUName = CPU; + if (CPUName.empty() || CPU == "generic") { + // If cross-compiling with -march=ppc64le without -mcpu + if (TargetTriple.getArch() == Triple::ppc64le) + CPUName = "ppc64le"; + else + CPUName = "generic"; + } + + // Initialize scheduling itinerary for the specified CPU. + InstrItins = getInstrItineraryForCPU(CPUName); + + // Parse features string. + ParseSubtargetFeatures(CPUName, FS); + + // If the user requested use of 64-bit regs, but the cpu selected doesn't + // support it, ignore. + if (IsPPC64 && has64BitSupport()) + Use64BitRegs = true; + + // Set up darwin-specific properties. + if (isDarwin()) + HasLazyResolverStubs = true; + + if ((TargetTriple.isOSFreeBSD() && TargetTriple.getOSMajorVersion() >= 13) || + TargetTriple.isOSNetBSD() || TargetTriple.isOSOpenBSD() || + TargetTriple.isMusl()) + SecurePlt = true; + + if (HasSPE && IsPPC64) + report_fatal_error( "SPE is only supported for 32-bit targets.\n", false); + if (HasSPE && (HasAltivec || HasQPX || HasVSX || HasFPU)) + report_fatal_error( + "SPE and traditional floating point cannot both be enabled.\n", false); + + // If not SPE, set standard FPU + if (!HasSPE) + HasFPU = true; + + // QPX requires a 32-byte aligned stack. Note that we need to do this if + // we're compiling for a BG/Q system regardless of whether or not QPX + // is enabled because external functions will assume this alignment. + IsQPXStackUnaligned = QPXStackUnaligned; + StackAlignment = getPlatformStackAlignment(); + + // Determine endianness. + // FIXME: Part of the TargetMachine. + IsLittleEndian = (TargetTriple.getArch() == Triple::ppc64le); +} + +/// Return true if accesses to the specified global have to go through a dyld +/// lazy resolution stub. This means that an extra load is required to get the +/// address of the global. +bool PPCSubtarget::hasLazyResolverStub(const GlobalValue *GV) const { + if (!HasLazyResolverStubs) + return false; + if (!TM.shouldAssumeDSOLocal(*GV->getParent(), GV)) + return true; + // 32 bit macho has no relocation for a-b if a is undefined, even if b is in + // the section that is being relocated. This means we have to use o load even + // for GVs that are known to be local to the dso. + if (GV->isDeclarationForLinker() || GV->hasCommonLinkage()) + return true; + return false; +} + +bool PPCSubtarget::enableMachineScheduler() const { return true; } + +bool PPCSubtarget::enableMachinePipeliner() const { + return (DarwinDirective == PPC::DIR_PWR9) && EnableMachinePipeliner; +} + +bool PPCSubtarget::useDFAforSMS() const { return false; } + +// This overrides the PostRAScheduler bit in the SchedModel for each CPU. +bool PPCSubtarget::enablePostRAScheduler() const { return true; } + +PPCGenSubtargetInfo::AntiDepBreakMode PPCSubtarget::getAntiDepBreakMode() const { + return TargetSubtargetInfo::ANTIDEP_ALL; +} + +void PPCSubtarget::getCriticalPathRCs(RegClassVector &CriticalPathRCs) const { + CriticalPathRCs.clear(); + CriticalPathRCs.push_back(isPPC64() ? + &PPC::G8RCRegClass : &PPC::GPRCRegClass); +} + +void PPCSubtarget::overrideSchedPolicy(MachineSchedPolicy &Policy, + unsigned NumRegionInstrs) const { + // The GenericScheduler that we use defaults to scheduling bottom up only. + // We want to schedule from both the top and the bottom and so we set + // OnlyBottomUp to false. + // We want to do bi-directional scheduling since it provides a more balanced + // schedule leading to better performance. + Policy.OnlyBottomUp = false; + // Spilling is generally expensive on all PPC cores, so always enable + // register-pressure tracking. + Policy.ShouldTrackPressure = true; +} + +bool PPCSubtarget::useAA() const { + return true; +} + +bool PPCSubtarget::enableSubRegLiveness() const { + return UseSubRegLiveness; +} + +unsigned char +PPCSubtarget::classifyGlobalReference(const GlobalValue *GV) const { + // Note that currently we don't generate non-pic references. + // If a caller wants that, this will have to be updated. + + // Large code model always uses the TOC even for local symbols. + if (TM.getCodeModel() == CodeModel::Large) + return PPCII::MO_PIC_FLAG | PPCII::MO_NLP_FLAG; + + if (TM.shouldAssumeDSOLocal(*GV->getParent(), GV)) + return PPCII::MO_PIC_FLAG; + return PPCII::MO_PIC_FLAG | PPCII::MO_NLP_FLAG; +} + +bool PPCSubtarget::isELFv2ABI() const { return TM.isELFv2ABI(); } +bool PPCSubtarget::isPPC64() const { return TM.isPPC64(); } |