| //===--- ARM.cpp - ARM (not AArch64) Helpers for Tools ----------*- C++ -*-===// |
| // |
| // 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 |
| // |
| //===----------------------------------------------------------------------===// |
| |
| #include "ARM.h" |
| #include "clang/Driver/Driver.h" |
| #include "clang/Driver/DriverDiagnostic.h" |
| #include "clang/Driver/Options.h" |
| #include "llvm/ADT/StringSwitch.h" |
| #include "llvm/Option/ArgList.h" |
| #include "llvm/Support/TargetParser.h" |
| #include "llvm/Support/Host.h" |
| |
| using namespace clang::driver; |
| using namespace clang::driver::tools; |
| using namespace clang; |
| using namespace llvm::opt; |
| |
| // Get SubArch (vN). |
| int arm::getARMSubArchVersionNumber(const llvm::Triple &Triple) { |
| llvm::StringRef Arch = Triple.getArchName(); |
| return llvm::ARM::parseArchVersion(Arch); |
| } |
| |
| // True if M-profile. |
| bool arm::isARMMProfile(const llvm::Triple &Triple) { |
| llvm::StringRef Arch = Triple.getArchName(); |
| return llvm::ARM::parseArchProfile(Arch) == llvm::ARM::ProfileKind::M; |
| } |
| |
| // Get Arch/CPU from args. |
| void arm::getARMArchCPUFromArgs(const ArgList &Args, llvm::StringRef &Arch, |
| llvm::StringRef &CPU, bool FromAs) { |
| if (const Arg *A = Args.getLastArg(clang::driver::options::OPT_mcpu_EQ)) |
| CPU = A->getValue(); |
| if (const Arg *A = Args.getLastArg(options::OPT_march_EQ)) |
| Arch = A->getValue(); |
| if (!FromAs) |
| return; |
| |
| for (const Arg *A : |
| Args.filtered(options::OPT_Wa_COMMA, options::OPT_Xassembler)) { |
| StringRef Value = A->getValue(); |
| if (Value.startswith("-mcpu=")) |
| CPU = Value.substr(6); |
| if (Value.startswith("-march=")) |
| Arch = Value.substr(7); |
| } |
| } |
| |
| // Handle -mhwdiv=. |
| // FIXME: Use ARMTargetParser. |
| static void getARMHWDivFeatures(const Driver &D, const Arg *A, |
| const ArgList &Args, StringRef HWDiv, |
| std::vector<StringRef> &Features) { |
| unsigned HWDivID = llvm::ARM::parseHWDiv(HWDiv); |
| if (!llvm::ARM::getHWDivFeatures(HWDivID, Features)) |
| D.Diag(clang::diag::err_drv_clang_unsupported) << A->getAsString(Args); |
| } |
| |
| // Handle -mfpu=. |
| static void getARMFPUFeatures(const Driver &D, const Arg *A, |
| const ArgList &Args, StringRef FPU, |
| std::vector<StringRef> &Features) { |
| unsigned FPUID = llvm::ARM::parseFPU(FPU); |
| if (!llvm::ARM::getFPUFeatures(FPUID, Features)) |
| D.Diag(clang::diag::err_drv_clang_unsupported) << A->getAsString(Args); |
| } |
| |
| // Decode ARM features from string like +[no]featureA+[no]featureB+... |
| static bool DecodeARMFeatures(const Driver &D, StringRef text, |
| StringRef CPU, llvm::ARM::ArchKind ArchKind, |
| std::vector<StringRef> &Features) { |
| SmallVector<StringRef, 8> Split; |
| text.split(Split, StringRef("+"), -1, false); |
| |
| for (StringRef Feature : Split) { |
| if (!appendArchExtFeatures(CPU, ArchKind, Feature, Features)) |
| return false; |
| } |
| return true; |
| } |
| |
| static void DecodeARMFeaturesFromCPU(const Driver &D, StringRef CPU, |
| std::vector<StringRef> &Features) { |
| CPU = CPU.split("+").first; |
| if (CPU != "generic") { |
| llvm::ARM::ArchKind ArchKind = llvm::ARM::parseCPUArch(CPU); |
| unsigned Extension = llvm::ARM::getDefaultExtensions(CPU, ArchKind); |
| llvm::ARM::getExtensionFeatures(Extension, Features); |
| } |
| } |
| |
| // Check if -march is valid by checking if it can be canonicalised and parsed. |
| // getARMArch is used here instead of just checking the -march value in order |
| // to handle -march=native correctly. |
| static void checkARMArchName(const Driver &D, const Arg *A, const ArgList &Args, |
| llvm::StringRef ArchName, llvm::StringRef CPUName, |
| std::vector<StringRef> &Features, |
| const llvm::Triple &Triple) { |
| std::pair<StringRef, StringRef> Split = ArchName.split("+"); |
| |
| std::string MArch = arm::getARMArch(ArchName, Triple); |
| llvm::ARM::ArchKind ArchKind = llvm::ARM::parseArch(MArch); |
| if (ArchKind == llvm::ARM::ArchKind::INVALID || |
| (Split.second.size() && !DecodeARMFeatures( |
| D, Split.second, CPUName, ArchKind, Features))) |
| D.Diag(clang::diag::err_drv_clang_unsupported) << A->getAsString(Args); |
| } |
| |
| // Check -mcpu=. Needs ArchName to handle -mcpu=generic. |
| static void checkARMCPUName(const Driver &D, const Arg *A, const ArgList &Args, |
| llvm::StringRef CPUName, llvm::StringRef ArchName, |
| std::vector<StringRef> &Features, |
| const llvm::Triple &Triple) { |
| std::pair<StringRef, StringRef> Split = CPUName.split("+"); |
| |
| std::string CPU = arm::getARMTargetCPU(CPUName, ArchName, Triple); |
| llvm::ARM::ArchKind ArchKind = |
| arm::getLLVMArchKindForARM(CPU, ArchName, Triple); |
| if (ArchKind == llvm::ARM::ArchKind::INVALID || |
| (Split.second.size() && !DecodeARMFeatures( |
| D, Split.second, CPU, ArchKind, Features))) |
| D.Diag(clang::diag::err_drv_clang_unsupported) << A->getAsString(Args); |
| } |
| |
| bool arm::useAAPCSForMachO(const llvm::Triple &T) { |
| // The backend is hardwired to assume AAPCS for M-class processors, ensure |
| // the frontend matches that. |
| return T.getEnvironment() == llvm::Triple::EABI || |
| T.getOS() == llvm::Triple::UnknownOS || isARMMProfile(T); |
| } |
| |
| // Select mode for reading thread pointer (-mtp=soft/cp15). |
| arm::ReadTPMode arm::getReadTPMode(const ToolChain &TC, const ArgList &Args) { |
| if (Arg *A = Args.getLastArg(options::OPT_mtp_mode_EQ)) { |
| const Driver &D = TC.getDriver(); |
| arm::ReadTPMode ThreadPointer = |
| llvm::StringSwitch<arm::ReadTPMode>(A->getValue()) |
| .Case("cp15", ReadTPMode::Cp15) |
| .Case("soft", ReadTPMode::Soft) |
| .Default(ReadTPMode::Invalid); |
| if (ThreadPointer != ReadTPMode::Invalid) |
| return ThreadPointer; |
| if (StringRef(A->getValue()).empty()) |
| D.Diag(diag::err_drv_missing_arg_mtp) << A->getAsString(Args); |
| else |
| D.Diag(diag::err_drv_invalid_mtp) << A->getAsString(Args); |
| return ReadTPMode::Invalid; |
| } |
| return ReadTPMode::Soft; |
| } |
| |
| // Select the float ABI as determined by -msoft-float, -mhard-float, and |
| // -mfloat-abi=. |
| arm::FloatABI arm::getARMFloatABI(const ToolChain &TC, const ArgList &Args) { |
| const Driver &D = TC.getDriver(); |
| const llvm::Triple &Triple = TC.getEffectiveTriple(); |
| auto SubArch = getARMSubArchVersionNumber(Triple); |
| arm::FloatABI ABI = FloatABI::Invalid; |
| if (Arg *A = |
| Args.getLastArg(options::OPT_msoft_float, options::OPT_mhard_float, |
| options::OPT_mfloat_abi_EQ)) { |
| if (A->getOption().matches(options::OPT_msoft_float)) { |
| ABI = FloatABI::Soft; |
| } else if (A->getOption().matches(options::OPT_mhard_float)) { |
| ABI = FloatABI::Hard; |
| } else { |
| ABI = llvm::StringSwitch<arm::FloatABI>(A->getValue()) |
| .Case("soft", FloatABI::Soft) |
| .Case("softfp", FloatABI::SoftFP) |
| .Case("hard", FloatABI::Hard) |
| .Default(FloatABI::Invalid); |
| if (ABI == FloatABI::Invalid && !StringRef(A->getValue()).empty()) { |
| D.Diag(diag::err_drv_invalid_mfloat_abi) << A->getAsString(Args); |
| ABI = FloatABI::Soft; |
| } |
| } |
| |
| // It is incorrect to select hard float ABI on MachO platforms if the ABI is |
| // "apcs-gnu". |
| if (Triple.isOSBinFormatMachO() && !useAAPCSForMachO(Triple) && |
| ABI == FloatABI::Hard) { |
| D.Diag(diag::err_drv_unsupported_opt_for_target) << A->getAsString(Args) |
| << Triple.getArchName(); |
| } |
| } |
| |
| // If unspecified, choose the default based on the platform. |
| if (ABI == FloatABI::Invalid) { |
| switch (Triple.getOS()) { |
| case llvm::Triple::Darwin: |
| case llvm::Triple::MacOSX: |
| case llvm::Triple::IOS: |
| case llvm::Triple::TvOS: { |
| // Darwin defaults to "softfp" for v6 and v7. |
| ABI = (SubArch == 6 || SubArch == 7) ? FloatABI::SoftFP : FloatABI::Soft; |
| ABI = Triple.isWatchABI() ? FloatABI::Hard : ABI; |
| break; |
| } |
| case llvm::Triple::WatchOS: |
| ABI = FloatABI::Hard; |
| break; |
| |
| // FIXME: this is invalid for WindowsCE |
| case llvm::Triple::Win32: |
| ABI = FloatABI::Hard; |
| break; |
| |
| case llvm::Triple::NetBSD: |
| switch (Triple.getEnvironment()) { |
| case llvm::Triple::EABIHF: |
| case llvm::Triple::GNUEABIHF: |
| ABI = FloatABI::Hard; |
| break; |
| default: |
| ABI = FloatABI::Soft; |
| break; |
| } |
| break; |
| |
| case llvm::Triple::FreeBSD: |
| switch (Triple.getEnvironment()) { |
| case llvm::Triple::GNUEABIHF: |
| ABI = FloatABI::Hard; |
| break; |
| default: |
| // FreeBSD defaults to soft float |
| ABI = FloatABI::Soft; |
| break; |
| } |
| break; |
| |
| case llvm::Triple::OpenBSD: |
| ABI = FloatABI::SoftFP; |
| break; |
| |
| default: |
| switch (Triple.getEnvironment()) { |
| case llvm::Triple::GNUEABIHF: |
| case llvm::Triple::MuslEABIHF: |
| case llvm::Triple::EABIHF: |
| ABI = FloatABI::Hard; |
| break; |
| case llvm::Triple::GNUEABI: |
| case llvm::Triple::MuslEABI: |
| case llvm::Triple::EABI: |
| // EABI is always AAPCS, and if it was not marked 'hard', it's softfp |
| ABI = FloatABI::SoftFP; |
| break; |
| case llvm::Triple::Android: |
| ABI = (SubArch >= 7) ? FloatABI::SoftFP : FloatABI::Soft; |
| break; |
| default: |
| // Assume "soft", but warn the user we are guessing. |
| if (Triple.isOSBinFormatMachO() && |
| Triple.getSubArch() == llvm::Triple::ARMSubArch_v7em) |
| ABI = FloatABI::Hard; |
| else |
| ABI = FloatABI::Soft; |
| |
| if (Triple.getOS() != llvm::Triple::UnknownOS || |
| !Triple.isOSBinFormatMachO()) |
| D.Diag(diag::warn_drv_assuming_mfloat_abi_is) << "soft"; |
| break; |
| } |
| } |
| } |
| |
| assert(ABI != FloatABI::Invalid && "must select an ABI"); |
| return ABI; |
| } |
| |
| void arm::getARMTargetFeatures(const ToolChain &TC, |
| const llvm::Triple &Triple, |
| const ArgList &Args, |
| ArgStringList &CmdArgs, |
| std::vector<StringRef> &Features, |
| bool ForAS) { |
| const Driver &D = TC.getDriver(); |
| |
| bool KernelOrKext = |
| Args.hasArg(options::OPT_mkernel, options::OPT_fapple_kext); |
| arm::FloatABI ABI = arm::getARMFloatABI(TC, Args); |
| arm::ReadTPMode ThreadPointer = arm::getReadTPMode(TC, Args); |
| const Arg *WaCPU = nullptr, *WaFPU = nullptr; |
| const Arg *WaHDiv = nullptr, *WaArch = nullptr; |
| |
| // This vector will accumulate features from the architecture |
| // extension suffixes on -mcpu and -march (e.g. the 'bar' in |
| // -mcpu=foo+bar). We want to apply those after the features derived |
| // from the FPU, in case -mfpu generates a negative feature which |
| // the +bar is supposed to override. |
| std::vector<StringRef> ExtensionFeatures; |
| |
| if (!ForAS) { |
| // FIXME: Note, this is a hack, the LLVM backend doesn't actually use these |
| // yet (it uses the -mfloat-abi and -msoft-float options), and it is |
| // stripped out by the ARM target. We should probably pass this a new |
| // -target-option, which is handled by the -cc1/-cc1as invocation. |
| // |
| // FIXME2: For consistency, it would be ideal if we set up the target |
| // machine state the same when using the frontend or the assembler. We don't |
| // currently do that for the assembler, we pass the options directly to the |
| // backend and never even instantiate the frontend TargetInfo. If we did, |
| // and used its handleTargetFeatures hook, then we could ensure the |
| // assembler and the frontend behave the same. |
| |
| // Use software floating point operations? |
| if (ABI == arm::FloatABI::Soft) |
| Features.push_back("+soft-float"); |
| |
| // Use software floating point argument passing? |
| if (ABI != arm::FloatABI::Hard) |
| Features.push_back("+soft-float-abi"); |
| } else { |
| // Here, we make sure that -Wa,-mfpu/cpu/arch/hwdiv will be passed down |
| // to the assembler correctly. |
| for (const Arg *A : |
| Args.filtered(options::OPT_Wa_COMMA, options::OPT_Xassembler)) { |
| StringRef Value = A->getValue(); |
| if (Value.startswith("-mfpu=")) { |
| WaFPU = A; |
| } else if (Value.startswith("-mcpu=")) { |
| WaCPU = A; |
| } else if (Value.startswith("-mhwdiv=")) { |
| WaHDiv = A; |
| } else if (Value.startswith("-march=")) { |
| WaArch = A; |
| } |
| } |
| } |
| |
| if (ThreadPointer == arm::ReadTPMode::Cp15) |
| Features.push_back("+read-tp-hard"); |
| |
| const Arg *ArchArg = Args.getLastArg(options::OPT_march_EQ); |
| const Arg *CPUArg = Args.getLastArg(options::OPT_mcpu_EQ); |
| StringRef ArchName; |
| StringRef CPUName; |
| |
| // Check -mcpu. ClangAs gives preference to -Wa,-mcpu=. |
| if (WaCPU) { |
| if (CPUArg) |
| D.Diag(clang::diag::warn_drv_unused_argument) |
| << CPUArg->getAsString(Args); |
| CPUName = StringRef(WaCPU->getValue()).substr(6); |
| CPUArg = WaCPU; |
| } else if (CPUArg) |
| CPUName = CPUArg->getValue(); |
| |
| // Check -march. ClangAs gives preference to -Wa,-march=. |
| if (WaArch) { |
| if (ArchArg) |
| D.Diag(clang::diag::warn_drv_unused_argument) |
| << ArchArg->getAsString(Args); |
| ArchName = StringRef(WaArch->getValue()).substr(7); |
| checkARMArchName(D, WaArch, Args, ArchName, CPUName, |
| ExtensionFeatures, Triple); |
| // FIXME: Set Arch. |
| D.Diag(clang::diag::warn_drv_unused_argument) << WaArch->getAsString(Args); |
| } else if (ArchArg) { |
| ArchName = ArchArg->getValue(); |
| checkARMArchName(D, ArchArg, Args, ArchName, CPUName, |
| ExtensionFeatures, Triple); |
| } |
| |
| // Add CPU features for generic CPUs |
| if (CPUName == "native") { |
| llvm::StringMap<bool> HostFeatures; |
| if (llvm::sys::getHostCPUFeatures(HostFeatures)) |
| for (auto &F : HostFeatures) |
| Features.push_back( |
| Args.MakeArgString((F.second ? "+" : "-") + F.first())); |
| } else if (!CPUName.empty()) { |
| // This sets the default features for the specified CPU. We certainly don't |
| // want to override the features that have been explicitly specified on the |
| // command line. Therefore, process them directly instead of appending them |
| // at the end later. |
| DecodeARMFeaturesFromCPU(D, CPUName, Features); |
| } |
| |
| if (CPUArg) |
| checkARMCPUName(D, CPUArg, Args, CPUName, ArchName, |
| ExtensionFeatures, Triple); |
| // Honor -mfpu=. ClangAs gives preference to -Wa,-mfpu=. |
| const Arg *FPUArg = Args.getLastArg(options::OPT_mfpu_EQ); |
| if (WaFPU) { |
| if (FPUArg) |
| D.Diag(clang::diag::warn_drv_unused_argument) |
| << FPUArg->getAsString(Args); |
| getARMFPUFeatures(D, WaFPU, Args, StringRef(WaFPU->getValue()).substr(6), |
| Features); |
| } else if (FPUArg) { |
| getARMFPUFeatures(D, FPUArg, Args, FPUArg->getValue(), Features); |
| } else if (Triple.isAndroid() && getARMSubArchVersionNumber(Triple) >= 7) { |
| const char *AndroidFPU = "neon"; |
| if (!llvm::ARM::getFPUFeatures(llvm::ARM::parseFPU(AndroidFPU), Features)) |
| D.Diag(clang::diag::err_drv_clang_unsupported) |
| << std::string("-mfpu=") + AndroidFPU; |
| } |
| |
| // Now we've finished accumulating features from arch, cpu and fpu, |
| // we can append the ones for architecture extensions that we |
| // collected separately. |
| Features.insert(std::end(Features), |
| std::begin(ExtensionFeatures), std::end(ExtensionFeatures)); |
| |
| // Honor -mhwdiv=. ClangAs gives preference to -Wa,-mhwdiv=. |
| const Arg *HDivArg = Args.getLastArg(options::OPT_mhwdiv_EQ); |
| if (WaHDiv) { |
| if (HDivArg) |
| D.Diag(clang::diag::warn_drv_unused_argument) |
| << HDivArg->getAsString(Args); |
| getARMHWDivFeatures(D, WaHDiv, Args, |
| StringRef(WaHDiv->getValue()).substr(8), Features); |
| } else if (HDivArg) |
| getARMHWDivFeatures(D, HDivArg, Args, HDivArg->getValue(), Features); |
| |
| // Handle (arch-dependent) fp16fml/fullfp16 relationship. |
| // Must happen before any features are disabled due to soft-float. |
| // FIXME: this fp16fml option handling will be reimplemented after the |
| // TargetParser rewrite. |
| const auto ItRNoFullFP16 = std::find(Features.rbegin(), Features.rend(), "-fullfp16"); |
| const auto ItRFP16FML = std::find(Features.rbegin(), Features.rend(), "+fp16fml"); |
| if (Triple.getSubArch() == llvm::Triple::SubArchType::ARMSubArch_v8_4a) { |
| const auto ItRFullFP16 = std::find(Features.rbegin(), Features.rend(), "+fullfp16"); |
| if (ItRFullFP16 < ItRNoFullFP16 && ItRFullFP16 < ItRFP16FML) { |
| // Only entangled feature that can be to the right of this +fullfp16 is -fp16fml. |
| // Only append the +fp16fml if there is no -fp16fml after the +fullfp16. |
| if (std::find(Features.rbegin(), ItRFullFP16, "-fp16fml") == ItRFullFP16) |
| Features.push_back("+fp16fml"); |
| } |
| else |
| goto fp16_fml_fallthrough; |
| } |
| else { |
| fp16_fml_fallthrough: |
| // In both of these cases, putting the 'other' feature on the end of the vector will |
| // result in the same effect as placing it immediately after the current feature. |
| if (ItRNoFullFP16 < ItRFP16FML) |
| Features.push_back("-fp16fml"); |
| else if (ItRNoFullFP16 > ItRFP16FML) |
| Features.push_back("+fullfp16"); |
| } |
| |
| // Setting -msoft-float/-mfloat-abi=soft effectively disables the FPU (GCC |
| // ignores the -mfpu options in this case). |
| // Note that the ABI can also be set implicitly by the target selected. |
| if (ABI == arm::FloatABI::Soft) { |
| llvm::ARM::getFPUFeatures(llvm::ARM::FK_NONE, Features); |
| |
| // Disable all features relating to hardware FP. |
| // FIXME: Disabling fpregs should be enough all by itself, since all |
| // the other FP features are dependent on it. However |
| // there is currently no easy way to test this in clang, so for |
| // now just be explicit and disable all known dependent features |
| // as well. |
| for (std::string Feature : { |
| "vfp2", "vfp2sp", |
| "vfp3", "vfp3sp", "vfp3d16", "vfp3d16sp", |
| "vfp4", "vfp4sp", "vfp4d16", "vfp4d16sp", |
| "fp-armv8", "fp-armv8sp", "fp-armv8d16", "fp-armv8d16sp", |
| "fullfp16", "neon", "crypto", "dotprod", "fp16fml", |
| "mve", "mve.fp", |
| "fp64", "d32", "fpregs"}) |
| Features.push_back(Args.MakeArgString("-" + Feature)); |
| } |
| |
| // En/disable crc code generation. |
| if (Arg *A = Args.getLastArg(options::OPT_mcrc, options::OPT_mnocrc)) { |
| if (A->getOption().matches(options::OPT_mcrc)) |
| Features.push_back("+crc"); |
| else |
| Features.push_back("-crc"); |
| } |
| |
| // For Arch >= ARMv8.0 && A profile: crypto = sha2 + aes |
| // FIXME: this needs reimplementation after the TargetParser rewrite |
| auto CryptoIt = llvm::find_if(llvm::reverse(Features), [](const StringRef F) { |
| return F.contains("crypto"); |
| }); |
| if (CryptoIt != Features.rend()) { |
| if (CryptoIt->take_front() == "+") { |
| StringRef ArchSuffix = arm::getLLVMArchSuffixForARM( |
| arm::getARMTargetCPU(CPUName, ArchName, Triple), ArchName, Triple); |
| if (llvm::ARM::parseArchVersion(ArchSuffix) >= 8 && |
| llvm::ARM::parseArchProfile(ArchSuffix) == |
| llvm::ARM::ProfileKind::A) { |
| if (ArchName.find_lower("+nosha2") == StringRef::npos && |
| CPUName.find_lower("+nosha2") == StringRef::npos) |
| Features.push_back("+sha2"); |
| if (ArchName.find_lower("+noaes") == StringRef::npos && |
| CPUName.find_lower("+noaes") == StringRef::npos) |
| Features.push_back("+aes"); |
| } else { |
| D.Diag(clang::diag::warn_target_unsupported_extension) |
| << "crypto" |
| << llvm::ARM::getArchName(llvm::ARM::parseArch(ArchSuffix)); |
| // With -fno-integrated-as -mfpu=crypto-neon-fp-armv8 some assemblers such as the GNU assembler |
| // will permit the use of crypto instructions as the fpu will override the architecture. |
| // We keep the crypto feature in this case to preserve compatibility. |
| // In all other cases we remove the crypto feature. |
| if (!Args.hasArg(options::OPT_fno_integrated_as)) |
| Features.push_back("-crypto"); |
| } |
| } |
| } |
| |
| // CMSE: Check for target 8M (for -mcmse to be applicable) is performed later. |
| if (Args.getLastArg(options::OPT_mcmse)) |
| Features.push_back("+8msecext"); |
| |
| // Look for the last occurrence of -mlong-calls or -mno-long-calls. If |
| // neither options are specified, see if we are compiling for kernel/kext and |
| // decide whether to pass "+long-calls" based on the OS and its version. |
| if (Arg *A = Args.getLastArg(options::OPT_mlong_calls, |
| options::OPT_mno_long_calls)) { |
| if (A->getOption().matches(options::OPT_mlong_calls)) |
| Features.push_back("+long-calls"); |
| } else if (KernelOrKext && (!Triple.isiOS() || Triple.isOSVersionLT(6)) && |
| !Triple.isWatchOS()) { |
| Features.push_back("+long-calls"); |
| } |
| |
| // Generate execute-only output (no data access to code sections). |
| // This only makes sense for the compiler, not for the assembler. |
| if (!ForAS) { |
| // Supported only on ARMv6T2 and ARMv7 and above. |
| // Cannot be combined with -mno-movt or -mlong-calls |
| if (Arg *A = Args.getLastArg(options::OPT_mexecute_only, options::OPT_mno_execute_only)) { |
| if (A->getOption().matches(options::OPT_mexecute_only)) { |
| if (getARMSubArchVersionNumber(Triple) < 7 && |
| llvm::ARM::parseArch(Triple.getArchName()) != llvm::ARM::ArchKind::ARMV6T2) |
| D.Diag(diag::err_target_unsupported_execute_only) << Triple.getArchName(); |
| else if (Arg *B = Args.getLastArg(options::OPT_mno_movt)) |
| D.Diag(diag::err_opt_not_valid_with_opt) << A->getAsString(Args) << B->getAsString(Args); |
| // Long calls create constant pool entries and have not yet been fixed up |
| // to play nicely with execute-only. Hence, they cannot be used in |
| // execute-only code for now |
| else if (Arg *B = Args.getLastArg(options::OPT_mlong_calls, options::OPT_mno_long_calls)) { |
| if (B->getOption().matches(options::OPT_mlong_calls)) |
| D.Diag(diag::err_opt_not_valid_with_opt) << A->getAsString(Args) << B->getAsString(Args); |
| } |
| Features.push_back("+execute-only"); |
| } |
| } |
| } |
| |
| // Kernel code has more strict alignment requirements. |
| if (KernelOrKext) |
| Features.push_back("+strict-align"); |
| else if (Arg *A = Args.getLastArg(options::OPT_mno_unaligned_access, |
| options::OPT_munaligned_access)) { |
| if (A->getOption().matches(options::OPT_munaligned_access)) { |
| // No v6M core supports unaligned memory access (v6M ARM ARM A3.2). |
| if (Triple.getSubArch() == llvm::Triple::SubArchType::ARMSubArch_v6m) |
| D.Diag(diag::err_target_unsupported_unaligned) << "v6m"; |
| // v8M Baseline follows on from v6M, so doesn't support unaligned memory |
| // access either. |
| else if (Triple.getSubArch() == llvm::Triple::SubArchType::ARMSubArch_v8m_baseline) |
| D.Diag(diag::err_target_unsupported_unaligned) << "v8m.base"; |
| } else |
| Features.push_back("+strict-align"); |
| } else { |
| // Assume pre-ARMv6 doesn't support unaligned accesses. |
| // |
| // ARMv6 may or may not support unaligned accesses depending on the |
| // SCTLR.U bit, which is architecture-specific. We assume ARMv6 |
| // Darwin and NetBSD targets support unaligned accesses, and others don't. |
| // |
| // ARMv7 always has SCTLR.U set to 1, but it has a new SCTLR.A bit |
| // which raises an alignment fault on unaligned accesses. Linux |
| // defaults this bit to 0 and handles it as a system-wide (not |
| // per-process) setting. It is therefore safe to assume that ARMv7+ |
| // Linux targets support unaligned accesses. The same goes for NaCl. |
| // |
| // The above behavior is consistent with GCC. |
| int VersionNum = getARMSubArchVersionNumber(Triple); |
| if (Triple.isOSDarwin() || Triple.isOSNetBSD()) { |
| if (VersionNum < 6 || |
| Triple.getSubArch() == llvm::Triple::SubArchType::ARMSubArch_v6m) |
| Features.push_back("+strict-align"); |
| } else if (Triple.isOSLinux() || Triple.isOSNaCl()) { |
| if (VersionNum < 7) |
| Features.push_back("+strict-align"); |
| } else |
| Features.push_back("+strict-align"); |
| } |
| |
| // llvm does not support reserving registers in general. There is support |
| // for reserving r9 on ARM though (defined as a platform-specific register |
| // in ARM EABI). |
| if (Args.hasArg(options::OPT_ffixed_r9)) |
| Features.push_back("+reserve-r9"); |
| |
| // The kext linker doesn't know how to deal with movw/movt. |
| if (KernelOrKext || Args.hasArg(options::OPT_mno_movt)) |
| Features.push_back("+no-movt"); |
| |
| if (Args.hasArg(options::OPT_mno_neg_immediates)) |
| Features.push_back("+no-neg-immediates"); |
| } |
| |
| const std::string arm::getARMArch(StringRef Arch, const llvm::Triple &Triple) { |
| std::string MArch; |
| if (!Arch.empty()) |
| MArch = Arch; |
| else |
| MArch = Triple.getArchName(); |
| MArch = StringRef(MArch).split("+").first.lower(); |
| |
| // Handle -march=native. |
| if (MArch == "native") { |
| std::string CPU = llvm::sys::getHostCPUName(); |
| if (CPU != "generic") { |
| // Translate the native cpu into the architecture suffix for that CPU. |
| StringRef Suffix = arm::getLLVMArchSuffixForARM(CPU, MArch, Triple); |
| // If there is no valid architecture suffix for this CPU we don't know how |
| // to handle it, so return no architecture. |
| if (Suffix.empty()) |
| MArch = ""; |
| else |
| MArch = std::string("arm") + Suffix.str(); |
| } |
| } |
| |
| return MArch; |
| } |
| |
| /// Get the (LLVM) name of the minimum ARM CPU for the arch we are targeting. |
| StringRef arm::getARMCPUForMArch(StringRef Arch, const llvm::Triple &Triple) { |
| std::string MArch = getARMArch(Arch, Triple); |
| // getARMCPUForArch defaults to the triple if MArch is empty, but empty MArch |
| // here means an -march=native that we can't handle, so instead return no CPU. |
| if (MArch.empty()) |
| return StringRef(); |
| |
| // We need to return an empty string here on invalid MArch values as the |
| // various places that call this function can't cope with a null result. |
| return Triple.getARMCPUForArch(MArch); |
| } |
| |
| /// getARMTargetCPU - Get the (LLVM) name of the ARM cpu we are targeting. |
| std::string arm::getARMTargetCPU(StringRef CPU, StringRef Arch, |
| const llvm::Triple &Triple) { |
| // FIXME: Warn on inconsistent use of -mcpu and -march. |
| // If we have -mcpu=, use that. |
| if (!CPU.empty()) { |
| std::string MCPU = StringRef(CPU).split("+").first.lower(); |
| // Handle -mcpu=native. |
| if (MCPU == "native") |
| return llvm::sys::getHostCPUName(); |
| else |
| return MCPU; |
| } |
| |
| return getARMCPUForMArch(Arch, Triple); |
| } |
| |
| /// getLLVMArchSuffixForARM - Get the LLVM ArchKind value to use for a |
| /// particular CPU (or Arch, if CPU is generic). This is needed to |
| /// pass to functions like llvm::ARM::getDefaultFPU which need an |
| /// ArchKind as well as a CPU name. |
| llvm::ARM::ArchKind arm::getLLVMArchKindForARM(StringRef CPU, StringRef Arch, |
| const llvm::Triple &Triple) { |
| llvm::ARM::ArchKind ArchKind; |
| if (CPU == "generic" || CPU.empty()) { |
| std::string ARMArch = tools::arm::getARMArch(Arch, Triple); |
| ArchKind = llvm::ARM::parseArch(ARMArch); |
| if (ArchKind == llvm::ARM::ArchKind::INVALID) |
| // In case of generic Arch, i.e. "arm", |
| // extract arch from default cpu of the Triple |
| ArchKind = llvm::ARM::parseCPUArch(Triple.getARMCPUForArch(ARMArch)); |
| } else { |
| // FIXME: horrible hack to get around the fact that Cortex-A7 is only an |
| // armv7k triple if it's actually been specified via "-arch armv7k". |
| ArchKind = (Arch == "armv7k" || Arch == "thumbv7k") |
| ? llvm::ARM::ArchKind::ARMV7K |
| : llvm::ARM::parseCPUArch(CPU); |
| } |
| return ArchKind; |
| } |
| |
| /// getLLVMArchSuffixForARM - Get the LLVM arch name to use for a particular |
| /// CPU (or Arch, if CPU is generic). |
| // FIXME: This is redundant with -mcpu, why does LLVM use this. |
| StringRef arm::getLLVMArchSuffixForARM(StringRef CPU, StringRef Arch, |
| const llvm::Triple &Triple) { |
| llvm::ARM::ArchKind ArchKind = getLLVMArchKindForARM(CPU, Arch, Triple); |
| if (ArchKind == llvm::ARM::ArchKind::INVALID) |
| return ""; |
| return llvm::ARM::getSubArch(ArchKind); |
| } |
| |
| void arm::appendBE8LinkFlag(const ArgList &Args, ArgStringList &CmdArgs, |
| const llvm::Triple &Triple) { |
| if (Args.hasArg(options::OPT_r)) |
| return; |
| |
| // ARMv7 (and later) and ARMv6-M do not support BE-32, so instruct the linker |
| // to generate BE-8 executables. |
| if (arm::getARMSubArchVersionNumber(Triple) >= 7 || arm::isARMMProfile(Triple)) |
| CmdArgs.push_back("--be8"); |
| } |
