-//===-- ARMSubtarget.cpp - ARM Subtarget Information ------------*- C++ -*-===//
+//===-- ARMSubtarget.cpp - ARM Subtarget Information ----------------------===//
//
// The LLVM Compiler Infrastructure
//
-// This file was developed by Evan Cheng and is distributed under the
-// University of Illinois Open Source License. See LICENSE.TXT for details.
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
-// This file implements the ARM specific subclass of TargetSubtarget.
+// This file implements the ARM specific subclass of TargetSubtargetInfo.
//
//===----------------------------------------------------------------------===//
#include "ARMSubtarget.h"
-#include "ARMGenSubtarget.inc"
-#include "llvm/Module.h"
+#include "ARMBaseInstrInfo.h"
+#include "ARMBaseRegisterInfo.h"
+#include "llvm/IR/Attributes.h"
+#include "llvm/IR/GlobalValue.h"
+#include "llvm/IR/Function.h"
#include "llvm/Support/CommandLine.h"
+#include "llvm/Target/TargetInstrInfo.h"
+
+#define GET_SUBTARGETINFO_TARGET_DESC
+#define GET_SUBTARGETINFO_CTOR
+#include "ARMGenSubtargetInfo.inc"
+
using namespace llvm;
-// FIXME: this is temporary.
-static cl::opt<bool> Thumb("enable-thumb",
- cl::desc("Switch to thumb mode in ARM backend"));
-
-ARMSubtarget::ARMSubtarget(const Module &M, const std::string &FS)
- : ARMArchVersion(V4T)
- , HasVFP2(false)
- , UseThumbBacktraces(false)
- , IsR9Reserved(false)
- , stackAlignment(8)
- , TargetType(isELF) { // Default to ELF unless otherwise specified.
-
- // Determine default and user specified characteristics
- std::string CPU = "generic";
-
- // Parse features string.
- ParseSubtargetFeatures(FS, CPU);
-
- IsThumb = Thumb;
-
- // Set the boolean corresponding to the current target triple, or the default
- // if one cannot be determined, to true.
- const std::string& TT = M.getTargetTriple();
- if (TT.length() > 5) {
- if (TT.find("-darwin") != std::string::npos)
- TargetType = isDarwin;
- } else if (TT.empty()) {
-#if defined(__APPLE__)
- TargetType = isDarwin;
-#endif
+static cl::opt<bool>
+ReserveR9("arm-reserve-r9", cl::Hidden,
+ cl::desc("Reserve R9, making it unavailable as GPR"));
+
+static cl::opt<bool>
+DarwinUseMOVT("arm-darwin-use-movt", cl::init(true), cl::Hidden);
+
+static cl::opt<bool>
+UseFusedMulOps("arm-use-mulops",
+ cl::init(true), cl::Hidden);
+
+static cl::opt<bool>
+StrictAlign("arm-strict-align", cl::Hidden,
+ cl::desc("Disallow all unaligned memory accesses"));
+
+ARMSubtarget::ARMSubtarget(const std::string &TT, const std::string &CPU,
+ const std::string &FS)
+ : ARMGenSubtargetInfo(TT, CPU, FS)
+ , ARMProcFamily(Others)
+ , stackAlignment(4)
+ , CPUString(CPU)
+ , TargetTriple(TT)
+ , TargetABI(ARM_ABI_APCS) {
+ initializeEnvironment();
+ resetSubtargetFeatures(CPU, FS);
+}
+
+void ARMSubtarget::initializeEnvironment() {
+ HasV4TOps = false;
+ HasV5TOps = false;
+ HasV5TEOps = false;
+ HasV6Ops = false;
+ HasV6T2Ops = false;
+ HasV7Ops = false;
+ HasVFPv2 = false;
+ HasVFPv3 = false;
+ HasVFPv4 = false;
+ HasNEON = false;
+ UseNEONForSinglePrecisionFP = false;
+ UseMulOps = UseFusedMulOps;
+ SlowFPVMLx = false;
+ HasVMLxForwarding = false;
+ SlowFPBrcc = false;
+ InThumbMode = false;
+ HasThumb2 = false;
+ IsMClass = false;
+ NoARM = false;
+ PostRAScheduler = false;
+ IsR9Reserved = ReserveR9;
+ UseMovt = false;
+ SupportsTailCall = false;
+ HasFP16 = false;
+ HasD16 = false;
+ HasHardwareDivide = false;
+ HasHardwareDivideInARM = false;
+ HasT2ExtractPack = false;
+ HasDataBarrier = false;
+ Pref32BitThumb = false;
+ AvoidCPSRPartialUpdate = false;
+ AvoidMOVsShifterOperand = false;
+ HasRAS = false;
+ HasMPExtension = false;
+ FPOnlySP = false;
+ AllowsUnalignedMem = false;
+ Thumb2DSP = false;
+ UseNaClTrap = false;
+}
+
+void ARMSubtarget::resetSubtargetFeatures(const MachineFunction *MF) {
+ AttributeSet FnAttrs = MF->getFunction()->getAttributes();
+ Attribute CPUAttr = FnAttrs.getAttribute(AttributeSet::FunctionIndex,
+ "target-cpu");
+ Attribute FSAttr = FnAttrs.getAttribute(AttributeSet::FunctionIndex,
+ "target-features");
+ std::string CPU =
+ !CPUAttr.hasAttribute(Attribute::None) ?CPUAttr.getValueAsString() : "";
+ std::string FS =
+ !FSAttr.hasAttribute(Attribute::None) ? FSAttr.getValueAsString() : "";
+ if (!FS.empty()) {
+ initializeEnvironment();
+ resetSubtargetFeatures(CPU, FS);
+ }
+}
+
+void ARMSubtarget::resetSubtargetFeatures(StringRef CPU, StringRef FS) {
+ if (CPUString.empty())
+ CPUString = "generic";
+
+ // Insert the architecture feature derived from the target triple into the
+ // feature string. This is important for setting features that are implied
+ // based on the architecture version.
+ std::string ArchFS = ARM_MC::ParseARMTriple(TargetTriple.getTriple(),
+ CPUString);
+ if (!FS.empty()) {
+ if (!ArchFS.empty())
+ ArchFS = ArchFS + "," + FS.str();
+ else
+ ArchFS = FS;
+ }
+ ParseSubtargetFeatures(CPUString, ArchFS);
+
+ // Thumb2 implies at least V6T2. FIXME: Fix tests to explicitly specify a
+ // ARM version or CPU and then remove this.
+ if (!HasV6T2Ops && hasThumb2())
+ HasV4TOps = HasV5TOps = HasV5TEOps = HasV6Ops = HasV6T2Ops = true;
+
+ // Keep a pointer to static instruction cost data for the specified CPU.
+ SchedModel = getSchedModelForCPU(CPUString);
+
+ // Initialize scheduling itinerary for the specified CPU.
+ InstrItins = getInstrItineraryForCPU(CPUString);
+
+ if ((TargetTriple.getTriple().find("eabi") != std::string::npos) ||
+ (isTargetIOS() && isMClass()))
+ // FIXME: We might want to separate AAPCS and EABI. Some systems, e.g.
+ // Darwin-EABI conforms to AACPS but not the rest of EABI.
+ TargetABI = ARM_ABI_AAPCS;
+
+ if (isAAPCS_ABI())
+ stackAlignment = 8;
+
+ if (!isTargetIOS())
+ UseMovt = hasV6T2Ops();
+ else {
+ IsR9Reserved = ReserveR9 | !HasV6Ops;
+ UseMovt = DarwinUseMOVT && hasV6T2Ops();
+ SupportsTailCall = !getTargetTriple().isOSVersionLT(5, 0);
+ }
+
+ if (!isThumb() || hasThumb2())
+ PostRAScheduler = true;
+
+ // v6+ may or may not support unaligned mem access depending on the system
+ // configuration.
+ if (!StrictAlign && hasV6Ops() && isTargetDarwin())
+ AllowsUnalignedMem = true;
+}
+
+/// GVIsIndirectSymbol - true if the GV will be accessed via an indirect symbol.
+bool
+ARMSubtarget::GVIsIndirectSymbol(const GlobalValue *GV,
+ Reloc::Model RelocM) const {
+ if (RelocM == Reloc::Static)
+ return false;
+
+ // Materializable GVs (in JIT lazy compilation mode) do not require an extra
+ // load from stub.
+ bool isDecl = GV->hasAvailableExternallyLinkage();
+ if (GV->isDeclaration() && !GV->isMaterializable())
+ isDecl = true;
+
+ if (!isTargetDarwin()) {
+ // Extra load is needed for all externally visible.
+ if (GV->hasLocalLinkage() || GV->hasHiddenVisibility())
+ return false;
+ return true;
+ } else {
+ if (RelocM == Reloc::PIC_) {
+ // If this is a strong reference to a definition, it is definitely not
+ // through a stub.
+ if (!isDecl && !GV->isWeakForLinker())
+ return false;
+
+ // Unless we have a symbol with hidden visibility, we have to go through a
+ // normal $non_lazy_ptr stub because this symbol might be resolved late.
+ if (!GV->hasHiddenVisibility()) // Non-hidden $non_lazy_ptr reference.
+ return true;
+
+ // If symbol visibility is hidden, we have a stub for common symbol
+ // references and external declarations.
+ if (isDecl || GV->hasCommonLinkage())
+ // Hidden $non_lazy_ptr reference.
+ return true;
+
+ return false;
+ } else {
+ // If this is a strong reference to a definition, it is definitely not
+ // through a stub.
+ if (!isDecl && !GV->isWeakForLinker())
+ return false;
+
+ // Unless we have a symbol with hidden visibility, we have to go through a
+ // normal $non_lazy_ptr stub because this symbol might be resolved late.
+ if (!GV->hasHiddenVisibility()) // Non-hidden $non_lazy_ptr reference.
+ return true;
+ }
}
- if (isTargetDarwin()) {
- UseThumbBacktraces = true;
- IsR9Reserved = true;
- stackAlignment = 4;
- }
+ return false;
+}
+
+unsigned ARMSubtarget::getMispredictionPenalty() const {
+ return SchedModel->MispredictPenalty;
+}
+
+bool ARMSubtarget::enablePostRAScheduler(
+ CodeGenOpt::Level OptLevel,
+ TargetSubtargetInfo::AntiDepBreakMode& Mode,
+ RegClassVector& CriticalPathRCs) const {
+ Mode = TargetSubtargetInfo::ANTIDEP_CRITICAL;
+ CriticalPathRCs.clear();
+ CriticalPathRCs.push_back(&ARM::GPRRegClass);
+ return PostRAScheduler && OptLevel >= CodeGenOpt::Default;
}