lib/Target/ARM/ARMLegalizerInfo.cpp - external/github.com/emscripten-core/emscripten-fastcomp - Git at Google

 //===- ARMLegalizerInfo.cpp --------------------------------------*- C++ -*-==//
 //
 //                     The LLVM Compiler Infrastructure
 //
 // This file is distributed under the University of Illinois Open Source
 // License. See LICENSE.TXT for details.
 //
 //===----------------------------------------------------------------------===//
 /// \file
 /// This file implements the targeting of the Machinelegalizer class for ARM.
 /// \todo This should be generated by TableGen.
 //===----------------------------------------------------------------------===//

 #include "ARMLegalizerInfo.h"
 #include "ARMCallLowering.h"
 #include "ARMSubtarget.h"
 #include "llvm/CodeGen/GlobalISel/LegalizerHelper.h"
 #include "llvm/CodeGen/LowLevelType.h"
 #include "llvm/CodeGen/MachineRegisterInfo.h"
 #include "llvm/CodeGen/TargetOpcodes.h"
 #include "llvm/CodeGen/ValueTypes.h"
 #include "llvm/IR/DerivedTypes.h"
 #include "llvm/IR/Type.h"

 using namespace llvm;

 /// FIXME: The following static functions are SizeChangeStrategy functions
 /// that are meant to temporarily mimic the behaviour of the old legalization
 /// based on doubling/halving non-legal types as closely as possible. This is
 /// not entirly possible as only legalizing the types that are exactly a power
 /// of 2 times the size of the legal types would require specifying all those
 /// sizes explicitly.
 /// In practice, not specifying those isn't a problem, and the below functions
 /// should disappear quickly as we add support for legalizing non-power-of-2
 /// sized types further.
 static void
 addAndInterleaveWithUnsupported(LegalizerInfo::SizeAndActionsVec &result,
                                 const LegalizerInfo::SizeAndActionsVec &v) {
   for (unsigned i = 0; i < v.size(); ++i) {
     result.push_back(v[i]);
     if (i + 1 < v[i].first && i + 1 < v.size() &&
         v[i + 1].first != v[i].first + 1)
       result.push_back({v[i].first + 1, LegalizerInfo::Unsupported});
   }
 }

 static LegalizerInfo::SizeAndActionsVec
 widen_8_16(const LegalizerInfo::SizeAndActionsVec &v) {
   assert(v.size() >= 1);
   assert(v[0].first > 17);
   LegalizerInfo::SizeAndActionsVec result = {
       {1, LegalizerInfo::Unsupported},
       {8, LegalizerInfo::WidenScalar},  {9, LegalizerInfo::Unsupported},
       {16, LegalizerInfo::WidenScalar}, {17, LegalizerInfo::Unsupported}};
   addAndInterleaveWithUnsupported(result, v);
   auto Largest = result.back().first;
   result.push_back({Largest + 1, LegalizerInfo::Unsupported});
   return result;
 }

 static LegalizerInfo::SizeAndActionsVec
 widen_1_8_16(const LegalizerInfo::SizeAndActionsVec &v) {
   assert(v.size() >= 1);
   assert(v[0].first > 17);
   LegalizerInfo::SizeAndActionsVec result = {
       {1, LegalizerInfo::WidenScalar},  {2, LegalizerInfo::Unsupported},
       {8, LegalizerInfo::WidenScalar},  {9, LegalizerInfo::Unsupported},
       {16, LegalizerInfo::WidenScalar}, {17, LegalizerInfo::Unsupported}};
   addAndInterleaveWithUnsupported(result, v);
   auto Largest = result.back().first;
   result.push_back({Largest + 1, LegalizerInfo::Unsupported});
   return result;
 }

 static bool AEABI(const ARMSubtarget &ST) {
   return ST.isTargetAEABI() || ST.isTargetGNUAEABI() || ST.isTargetMuslAEABI();
 }

 ARMLegalizerInfo::ARMLegalizerInfo(const ARMSubtarget &ST) {
   using namespace TargetOpcode;

   const LLT p0 = LLT::pointer(0, 32);

   const LLT s1 = LLT::scalar(1);
   const LLT s8 = LLT::scalar(8);
   const LLT s16 = LLT::scalar(16);
   const LLT s32 = LLT::scalar(32);
   const LLT s64 = LLT::scalar(64);

   setAction({G_GLOBAL_VALUE, p0}, Legal);
   setAction({G_FRAME_INDEX, p0}, Legal);

   for (unsigned Op : {G_LOAD, G_STORE}) {
     for (auto Ty : {s1, s8, s16, s32, p0})
       setAction({Op, Ty}, Legal);
     setAction({Op, 1, p0}, Legal);
   }

   for (unsigned Op : {G_ADD, G_SUB, G_MUL, G_AND, G_OR, G_XOR}) {
     if (Op != G_ADD)
       setLegalizeScalarToDifferentSizeStrategy(
           Op, 0, widenToLargerTypesUnsupportedOtherwise);
     setAction({Op, s32}, Legal);
   }

   for (unsigned Op : {G_SDIV, G_UDIV}) {
     setLegalizeScalarToDifferentSizeStrategy(Op, 0,
         widenToLargerTypesUnsupportedOtherwise);
     if (ST.hasDivideInARMMode())
       setAction({Op, s32}, Legal);
     else
       setAction({Op, s32}, Libcall);
   }

   for (unsigned Op : {G_SREM, G_UREM}) {
     setLegalizeScalarToDifferentSizeStrategy(Op, 0, widen_8_16);
     if (ST.hasDivideInARMMode())
       setAction({Op, s32}, Lower);
     else if (AEABI(ST))
       setAction({Op, s32}, Custom);
     else
       setAction({Op, s32}, Libcall);
   }

   for (unsigned Op : {G_SEXT, G_ZEXT, G_ANYEXT}) {
     setAction({Op, s32}, Legal);
   }

   setAction({G_INTTOPTR, p0}, Legal);
   setAction({G_INTTOPTR, 1, s32}, Legal);

   setAction({G_PTRTOINT, s32}, Legal);
   setAction({G_PTRTOINT, 1, p0}, Legal);

   for (unsigned Op : {G_ASHR, G_LSHR, G_SHL})
     setAction({Op, s32}, Legal);

   setAction({G_GEP, p0}, Legal);
   setAction({G_GEP, 1, s32}, Legal);

   setAction({G_SELECT, s32}, Legal);
   setAction({G_SELECT, p0}, Legal);
   setAction({G_SELECT, 1, s1}, Legal);

   setAction({G_BRCOND, s1}, Legal);

   setAction({G_CONSTANT, s32}, Legal);
   setAction({G_CONSTANT, p0}, Legal);
   setLegalizeScalarToDifferentSizeStrategy(G_CONSTANT, 0, widen_1_8_16);

   setAction({G_ICMP, s1}, Legal);
   setLegalizeScalarToDifferentSizeStrategy(G_ICMP, 1,
       widenToLargerTypesUnsupportedOtherwise);
   for (auto Ty : {s32, p0})
     setAction({G_ICMP, 1, Ty}, Legal);

   if (!ST.useSoftFloat() && ST.hasVFP2()) {
     for (unsigned BinOp : {G_FADD, G_FSUB, G_FMUL, G_FDIV})
       for (auto Ty : {s32, s64})
         setAction({BinOp, Ty}, Legal);

     setAction({G_LOAD, s64}, Legal);
     setAction({G_STORE, s64}, Legal);

     setAction({G_FCMP, s1}, Legal);
     setAction({G_FCMP, 1, s32}, Legal);
     setAction({G_FCMP, 1, s64}, Legal);

     setAction({G_MERGE_VALUES, s64}, Legal);
     setAction({G_MERGE_VALUES, 1, s32}, Legal);
     setAction({G_UNMERGE_VALUES, s32}, Legal);
     setAction({G_UNMERGE_VALUES, 1, s64}, Legal);
   } else {
     for (unsigned BinOp : {G_FADD, G_FSUB, G_FMUL, G_FDIV})
       for (auto Ty : {s32, s64})
         setAction({BinOp, Ty}, Libcall);

     setAction({G_FCMP, s1}, Legal);
     setAction({G_FCMP, 1, s32}, Custom);
     setAction({G_FCMP, 1, s64}, Custom);

     if (AEABI(ST))
       setFCmpLibcallsAEABI();
     else
       setFCmpLibcallsGNU();
   }

   for (unsigned Op : {G_FREM, G_FPOW})
     for (auto Ty : {s32, s64})
       setAction({Op, Ty}, Libcall);

   computeTables();
 }

 void ARMLegalizerInfo::setFCmpLibcallsAEABI() {
   // FCMP_TRUE and FCMP_FALSE don't need libcalls, they should be
   // default-initialized.
   FCmp32Libcalls.resize(CmpInst::LAST_FCMP_PREDICATE + 1);
   FCmp32Libcalls[CmpInst::FCMP_OEQ] = {
       {RTLIB::OEQ_F32, CmpInst::BAD_ICMP_PREDICATE}};
   FCmp32Libcalls[CmpInst::FCMP_OGE] = {
       {RTLIB::OGE_F32, CmpInst::BAD_ICMP_PREDICATE}};
   FCmp32Libcalls[CmpInst::FCMP_OGT] = {
       {RTLIB::OGT_F32, CmpInst::BAD_ICMP_PREDICATE}};
   FCmp32Libcalls[CmpInst::FCMP_OLE] = {
       {RTLIB::OLE_F32, CmpInst::BAD_ICMP_PREDICATE}};
   FCmp32Libcalls[CmpInst::FCMP_OLT] = {
       {RTLIB::OLT_F32, CmpInst::BAD_ICMP_PREDICATE}};
   FCmp32Libcalls[CmpInst::FCMP_ORD] = {{RTLIB::O_F32, CmpInst::ICMP_EQ}};
   FCmp32Libcalls[CmpInst::FCMP_UGE] = {{RTLIB::OLT_F32, CmpInst::ICMP_EQ}};
   FCmp32Libcalls[CmpInst::FCMP_UGT] = {{RTLIB::OLE_F32, CmpInst::ICMP_EQ}};
   FCmp32Libcalls[CmpInst::FCMP_ULE] = {{RTLIB::OGT_F32, CmpInst::ICMP_EQ}};
   FCmp32Libcalls[CmpInst::FCMP_ULT] = {{RTLIB::OGE_F32, CmpInst::ICMP_EQ}};
   FCmp32Libcalls[CmpInst::FCMP_UNE] = {{RTLIB::UNE_F32, CmpInst::ICMP_EQ}};
   FCmp32Libcalls[CmpInst::FCMP_UNO] = {
       {RTLIB::UO_F32, CmpInst::BAD_ICMP_PREDICATE}};
   FCmp32Libcalls[CmpInst::FCMP_ONE] = {
       {RTLIB::OGT_F32, CmpInst::BAD_ICMP_PREDICATE},
       {RTLIB::OLT_F32, CmpInst::BAD_ICMP_PREDICATE}};
   FCmp32Libcalls[CmpInst::FCMP_UEQ] = {
       {RTLIB::OEQ_F32, CmpInst::BAD_ICMP_PREDICATE},
       {RTLIB::UO_F32, CmpInst::BAD_ICMP_PREDICATE}};

   FCmp64Libcalls.resize(CmpInst::LAST_FCMP_PREDICATE + 1);
   FCmp64Libcalls[CmpInst::FCMP_OEQ] = {
       {RTLIB::OEQ_F64, CmpInst::BAD_ICMP_PREDICATE}};
   FCmp64Libcalls[CmpInst::FCMP_OGE] = {
       {RTLIB::OGE_F64, CmpInst::BAD_ICMP_PREDICATE}};
   FCmp64Libcalls[CmpInst::FCMP_OGT] = {
       {RTLIB::OGT_F64, CmpInst::BAD_ICMP_PREDICATE}};
   FCmp64Libcalls[CmpInst::FCMP_OLE] = {
       {RTLIB::OLE_F64, CmpInst::BAD_ICMP_PREDICATE}};
   FCmp64Libcalls[CmpInst::FCMP_OLT] = {
       {RTLIB::OLT_F64, CmpInst::BAD_ICMP_PREDICATE}};
   FCmp64Libcalls[CmpInst::FCMP_ORD] = {{RTLIB::O_F64, CmpInst::ICMP_EQ}};
   FCmp64Libcalls[CmpInst::FCMP_UGE] = {{RTLIB::OLT_F64, CmpInst::ICMP_EQ}};
   FCmp64Libcalls[CmpInst::FCMP_UGT] = {{RTLIB::OLE_F64, CmpInst::ICMP_EQ}};
   FCmp64Libcalls[CmpInst::FCMP_ULE] = {{RTLIB::OGT_F64, CmpInst::ICMP_EQ}};
   FCmp64Libcalls[CmpInst::FCMP_ULT] = {{RTLIB::OGE_F64, CmpInst::ICMP_EQ}};
   FCmp64Libcalls[CmpInst::FCMP_UNE] = {{RTLIB::UNE_F64, CmpInst::ICMP_EQ}};
   FCmp64Libcalls[CmpInst::FCMP_UNO] = {
       {RTLIB::UO_F64, CmpInst::BAD_ICMP_PREDICATE}};
   FCmp64Libcalls[CmpInst::FCMP_ONE] = {
       {RTLIB::OGT_F64, CmpInst::BAD_ICMP_PREDICATE},
       {RTLIB::OLT_F64, CmpInst::BAD_ICMP_PREDICATE}};
   FCmp64Libcalls[CmpInst::FCMP_UEQ] = {
       {RTLIB::OEQ_F64, CmpInst::BAD_ICMP_PREDICATE},
       {RTLIB::UO_F64, CmpInst::BAD_ICMP_PREDICATE}};
 }

 void ARMLegalizerInfo::setFCmpLibcallsGNU() {
   // FCMP_TRUE and FCMP_FALSE don't need libcalls, they should be
   // default-initialized.
   FCmp32Libcalls.resize(CmpInst::LAST_FCMP_PREDICATE + 1);
   FCmp32Libcalls[CmpInst::FCMP_OEQ] = {{RTLIB::OEQ_F32, CmpInst::ICMP_EQ}};
   FCmp32Libcalls[CmpInst::FCMP_OGE] = {{RTLIB::OGE_F32, CmpInst::ICMP_SGE}};
   FCmp32Libcalls[CmpInst::FCMP_OGT] = {{RTLIB::OGT_F32, CmpInst::ICMP_SGT}};
   FCmp32Libcalls[CmpInst::FCMP_OLE] = {{RTLIB::OLE_F32, CmpInst::ICMP_SLE}};
   FCmp32Libcalls[CmpInst::FCMP_OLT] = {{RTLIB::OLT_F32, CmpInst::ICMP_SLT}};
   FCmp32Libcalls[CmpInst::FCMP_ORD] = {{RTLIB::O_F32, CmpInst::ICMP_EQ}};
   FCmp32Libcalls[CmpInst::FCMP_UGE] = {{RTLIB::OLT_F32, CmpInst::ICMP_SGE}};
   FCmp32Libcalls[CmpInst::FCMP_UGT] = {{RTLIB::OLE_F32, CmpInst::ICMP_SGT}};
   FCmp32Libcalls[CmpInst::FCMP_ULE] = {{RTLIB::OGT_F32, CmpInst::ICMP_SLE}};
   FCmp32Libcalls[CmpInst::FCMP_ULT] = {{RTLIB::OGE_F32, CmpInst::ICMP_SLT}};
   FCmp32Libcalls[CmpInst::FCMP_UNE] = {{RTLIB::UNE_F32, CmpInst::ICMP_NE}};
   FCmp32Libcalls[CmpInst::FCMP_UNO] = {{RTLIB::UO_F32, CmpInst::ICMP_NE}};
   FCmp32Libcalls[CmpInst::FCMP_ONE] = {{RTLIB::OGT_F32, CmpInst::ICMP_SGT},
                                        {RTLIB::OLT_F32, CmpInst::ICMP_SLT}};
   FCmp32Libcalls[CmpInst::FCMP_UEQ] = {{RTLIB::OEQ_F32, CmpInst::ICMP_EQ},
                                        {RTLIB::UO_F32, CmpInst::ICMP_NE}};

   FCmp64Libcalls.resize(CmpInst::LAST_FCMP_PREDICATE + 1);
   FCmp64Libcalls[CmpInst::FCMP_OEQ] = {{RTLIB::OEQ_F64, CmpInst::ICMP_EQ}};
   FCmp64Libcalls[CmpInst::FCMP_OGE] = {{RTLIB::OGE_F64, CmpInst::ICMP_SGE}};
   FCmp64Libcalls[CmpInst::FCMP_OGT] = {{RTLIB::OGT_F64, CmpInst::ICMP_SGT}};
   FCmp64Libcalls[CmpInst::FCMP_OLE] = {{RTLIB::OLE_F64, CmpInst::ICMP_SLE}};
   FCmp64Libcalls[CmpInst::FCMP_OLT] = {{RTLIB::OLT_F64, CmpInst::ICMP_SLT}};
   FCmp64Libcalls[CmpInst::FCMP_ORD] = {{RTLIB::O_F64, CmpInst::ICMP_EQ}};
   FCmp64Libcalls[CmpInst::FCMP_UGE] = {{RTLIB::OLT_F64, CmpInst::ICMP_SGE}};
   FCmp64Libcalls[CmpInst::FCMP_UGT] = {{RTLIB::OLE_F64, CmpInst::ICMP_SGT}};
   FCmp64Libcalls[CmpInst::FCMP_ULE] = {{RTLIB::OGT_F64, CmpInst::ICMP_SLE}};
   FCmp64Libcalls[CmpInst::FCMP_ULT] = {{RTLIB::OGE_F64, CmpInst::ICMP_SLT}};
   FCmp64Libcalls[CmpInst::FCMP_UNE] = {{RTLIB::UNE_F64, CmpInst::ICMP_NE}};
   FCmp64Libcalls[CmpInst::FCMP_UNO] = {{RTLIB::UO_F64, CmpInst::ICMP_NE}};
   FCmp64Libcalls[CmpInst::FCMP_ONE] = {{RTLIB::OGT_F64, CmpInst::ICMP_SGT},
                                        {RTLIB::OLT_F64, CmpInst::ICMP_SLT}};
   FCmp64Libcalls[CmpInst::FCMP_UEQ] = {{RTLIB::OEQ_F64, CmpInst::ICMP_EQ},
                                        {RTLIB::UO_F64, CmpInst::ICMP_NE}};
 }

 ARMLegalizerInfo::FCmpLibcallsList
 ARMLegalizerInfo::getFCmpLibcalls(CmpInst::Predicate Predicate,
                                   unsigned Size) const {
   assert(CmpInst::isFPPredicate(Predicate) && "Unsupported FCmp predicate");
   if (Size == 32)
     return FCmp32Libcalls[Predicate];
   if (Size == 64)
     return FCmp64Libcalls[Predicate];
   llvm_unreachable("Unsupported size for FCmp predicate");
 }

 bool ARMLegalizerInfo::legalizeCustom(MachineInstr &MI,
                                       MachineRegisterInfo &MRI,
                                       MachineIRBuilder &MIRBuilder) const {
   using namespace TargetOpcode;

   MIRBuilder.setInstr(MI);

   switch (MI.getOpcode()) {
   default:
     return false;
   case G_SREM:
   case G_UREM: {
     unsigned OriginalResult = MI.getOperand(0).getReg();
     auto Size = MRI.getType(OriginalResult).getSizeInBits();
     if (Size != 32)
       return false;

     auto Libcall =
         MI.getOpcode() == G_SREM ? RTLIB::SDIVREM_I32 : RTLIB::UDIVREM_I32;

     // Our divmod libcalls return a struct containing the quotient and the
     // remainder. We need to create a virtual register for it.
     auto &Ctx = MIRBuilder.getMF().getFunction().getContext();
     Type *ArgTy = Type::getInt32Ty(Ctx);
     StructType *RetTy = StructType::get(Ctx, {ArgTy, ArgTy}, /* Packed */ true);
     auto RetVal = MRI.createGenericVirtualRegister(
         getLLTForType(*RetTy, MIRBuilder.getMF().getDataLayout()));

     auto Status = createLibcall(MIRBuilder, Libcall, {RetVal, RetTy},
                                 {{MI.getOperand(1).getReg(), ArgTy},
                                  {MI.getOperand(2).getReg(), ArgTy}});
     if (Status != LegalizerHelper::Legalized)
       return false;

     // The remainder is the second result of divmod. Split the return value into
     // a new, unused register for the quotient and the destination of the
     // original instruction for the remainder.
     MIRBuilder.buildUnmerge(
         {MRI.createGenericVirtualRegister(LLT::scalar(32)), OriginalResult},
         RetVal);
     break;
   }
   case G_FCMP: {
     assert(MRI.getType(MI.getOperand(2).getReg()) ==
                MRI.getType(MI.getOperand(3).getReg()) &&
            "Mismatched operands for G_FCMP");
     auto OpSize = MRI.getType(MI.getOperand(2).getReg()).getSizeInBits();

     auto OriginalResult = MI.getOperand(0).getReg();
     auto Predicate =
         static_cast<CmpInst::Predicate>(MI.getOperand(1).getPredicate());
     auto Libcalls = getFCmpLibcalls(Predicate, OpSize);

     if (Libcalls.empty()) {
       assert((Predicate == CmpInst::FCMP_TRUE ||
               Predicate == CmpInst::FCMP_FALSE) &&
              "Predicate needs libcalls, but none specified");
       MIRBuilder.buildConstant(OriginalResult,
                                Predicate == CmpInst::FCMP_TRUE ? 1 : 0);
       MI.eraseFromParent();
       return true;
     }

     auto &Ctx = MIRBuilder.getMF().getFunction().getContext();
     assert((OpSize == 32 || OpSize == 64) && "Unsupported operand size");
     auto *ArgTy = OpSize == 32 ? Type::getFloatTy(Ctx) : Type::getDoubleTy(Ctx);
     auto *RetTy = Type::getInt32Ty(Ctx);

     SmallVector<unsigned, 2> Results;
     for (auto Libcall : Libcalls) {
       auto LibcallResult = MRI.createGenericVirtualRegister(LLT::scalar(32));
       auto Status =
           createLibcall(MIRBuilder, Libcall.LibcallID, {LibcallResult, RetTy},
                         {{MI.getOperand(2).getReg(), ArgTy},
                          {MI.getOperand(3).getReg(), ArgTy}});

       if (Status != LegalizerHelper::Legalized)
         return false;

       auto ProcessedResult =
           Libcalls.size() == 1
               ? OriginalResult
               : MRI.createGenericVirtualRegister(MRI.getType(OriginalResult));

       // We have a result, but we need to transform it into a proper 1-bit 0 or
       // 1, taking into account the different peculiarities of the values
       // returned by the comparison functions.
       CmpInst::Predicate ResultPred = Libcall.Predicate;
       if (ResultPred == CmpInst::BAD_ICMP_PREDICATE) {
         // We have a nice 0 or 1, and we just need to truncate it back to 1 bit
         // to keep the types consistent.
         MIRBuilder.buildTrunc(ProcessedResult, LibcallResult);
       } else {
         // We need to compare against 0.
         assert(CmpInst::isIntPredicate(ResultPred) && "Unsupported predicate");
         auto Zero = MRI.createGenericVirtualRegister(LLT::scalar(32));
         MIRBuilder.buildConstant(Zero, 0);
         MIRBuilder.buildICmp(ResultPred, ProcessedResult, LibcallResult, Zero);
       }
       Results.push_back(ProcessedResult);
     }

     if (Results.size() != 1) {
       assert(Results.size() == 2 && "Unexpected number of results");
       MIRBuilder.buildOr(OriginalResult, Results[0], Results[1]);
     }
     break;
   }
   }

   MI.eraseFromParent();
   return true;
 }
	//===- ARMLegalizerInfo.cpp --------------------------------------- C++ --==//
	//
	// The LLVM Compiler Infrastructure
	//
	// This file is distributed under the University of Illinois Open Source
	// License. See LICENSE.TXT for details.
	//
	//===----------------------------------------------------------------------===//
	/// \file
	/// This file implements the targeting of the Machinelegalizer class for ARM.
	/// \todo This should be generated by TableGen.
	//===----------------------------------------------------------------------===//

	#include "ARMLegalizerInfo.h"
	#include "ARMCallLowering.h"
	#include "ARMSubtarget.h"
	#include "llvm/CodeGen/GlobalISel/LegalizerHelper.h"
	#include "llvm/CodeGen/LowLevelType.h"
	#include "llvm/CodeGen/MachineRegisterInfo.h"
	#include "llvm/CodeGen/TargetOpcodes.h"
	#include "llvm/CodeGen/ValueTypes.h"
	#include "llvm/IR/DerivedTypes.h"
	#include "llvm/IR/Type.h"

	using namespace llvm;

	/// FIXME: The following static functions are SizeChangeStrategy functions
	/// that are meant to temporarily mimic the behaviour of the old legalization
	/// based on doubling/halving non-legal types as closely as possible. This is
	/// not entirly possible as only legalizing the types that are exactly a power
	/// of 2 times the size of the legal types would require specifying all those
	/// sizes explicitly.
	/// In practice, not specifying those isn't a problem, and the below functions
	/// should disappear quickly as we add support for legalizing non-power-of-2
	/// sized types further.
	static void
	addAndInterleaveWithUnsupported(LegalizerInfo::SizeAndActionsVec &result,
	const LegalizerInfo::SizeAndActionsVec &v) {
	for (unsigned i = 0; i < v.size(); ++i) {
	result.push_back(v[i]);
	if (i + 1 < v[i].first && i + 1 < v.size() &&
	v[i + 1].first != v[i].first + 1)
	result.push_back({v[i].first + 1, LegalizerInfo::Unsupported});
	}
	}

	static LegalizerInfo::SizeAndActionsVec
	widen_8_16(const LegalizerInfo::SizeAndActionsVec &v) {
	assert(v.size() >= 1);
	assert(v[0].first > 17);
	LegalizerInfo::SizeAndActionsVec result = {
	{1, LegalizerInfo::Unsupported},
	{8, LegalizerInfo::WidenScalar}, {9, LegalizerInfo::Unsupported},
	{16, LegalizerInfo::WidenScalar}, {17, LegalizerInfo::Unsupported}};
	addAndInterleaveWithUnsupported(result, v);
	auto Largest = result.back().first;
	result.push_back({Largest + 1, LegalizerInfo::Unsupported});
	return result;
	}

	static LegalizerInfo::SizeAndActionsVec
	widen_1_8_16(const LegalizerInfo::SizeAndActionsVec &v) {
	assert(v.size() >= 1);
	assert(v[0].first > 17);
	LegalizerInfo::SizeAndActionsVec result = {
	{1, LegalizerInfo::WidenScalar}, {2, LegalizerInfo::Unsupported},
	{8, LegalizerInfo::WidenScalar}, {9, LegalizerInfo::Unsupported},
	{16, LegalizerInfo::WidenScalar}, {17, LegalizerInfo::Unsupported}};
	addAndInterleaveWithUnsupported(result, v);
	auto Largest = result.back().first;
	result.push_back({Largest + 1, LegalizerInfo::Unsupported});
	return result;
	}

	static bool AEABI(const ARMSubtarget &ST) {
	return ST.isTargetAEABI() \|\| ST.isTargetGNUAEABI() \|\| ST.isTargetMuslAEABI();
	}

	ARMLegalizerInfo::ARMLegalizerInfo(const ARMSubtarget &ST) {
	using namespace TargetOpcode;

	const LLT p0 = LLT::pointer(0, 32);

	const LLT s1 = LLT::scalar(1);
	const LLT s8 = LLT::scalar(8);
	const LLT s16 = LLT::scalar(16);
	const LLT s32 = LLT::scalar(32);
	const LLT s64 = LLT::scalar(64);

	setAction({G_GLOBAL_VALUE, p0}, Legal);
	setAction({G_FRAME_INDEX, p0}, Legal);

	for (unsigned Op : {G_LOAD, G_STORE}) {
	for (auto Ty : {s1, s8, s16, s32, p0})
	setAction({Op, Ty}, Legal);
	setAction({Op, 1, p0}, Legal);
	}

	for (unsigned Op : {G_ADD, G_SUB, G_MUL, G_AND, G_OR, G_XOR}) {
	if (Op != G_ADD)
	setLegalizeScalarToDifferentSizeStrategy(
	Op, 0, widenToLargerTypesUnsupportedOtherwise);
	setAction({Op, s32}, Legal);
	}

	for (unsigned Op : {G_SDIV, G_UDIV}) {
	setLegalizeScalarToDifferentSizeStrategy(Op, 0,
	widenToLargerTypesUnsupportedOtherwise);
	if (ST.hasDivideInARMMode())
	setAction({Op, s32}, Legal);
	else
	setAction({Op, s32}, Libcall);
	}

	for (unsigned Op : {G_SREM, G_UREM}) {
	setLegalizeScalarToDifferentSizeStrategy(Op, 0, widen_8_16);
	if (ST.hasDivideInARMMode())
	setAction({Op, s32}, Lower);
	else if (AEABI(ST))
	setAction({Op, s32}, Custom);
	else
	setAction({Op, s32}, Libcall);
	}

	for (unsigned Op : {G_SEXT, G_ZEXT, G_ANYEXT}) {
	setAction({Op, s32}, Legal);
	}

	setAction({G_INTTOPTR, p0}, Legal);
	setAction({G_INTTOPTR, 1, s32}, Legal);

	setAction({G_PTRTOINT, s32}, Legal);
	setAction({G_PTRTOINT, 1, p0}, Legal);

	for (unsigned Op : {G_ASHR, G_LSHR, G_SHL})
	setAction({Op, s32}, Legal);

	setAction({G_GEP, p0}, Legal);
	setAction({G_GEP, 1, s32}, Legal);

	setAction({G_SELECT, s32}, Legal);
	setAction({G_SELECT, p0}, Legal);
	setAction({G_SELECT, 1, s1}, Legal);

	setAction({G_BRCOND, s1}, Legal);

	setAction({G_CONSTANT, s32}, Legal);
	setAction({G_CONSTANT, p0}, Legal);
	setLegalizeScalarToDifferentSizeStrategy(G_CONSTANT, 0, widen_1_8_16);

	setAction({G_ICMP, s1}, Legal);
	setLegalizeScalarToDifferentSizeStrategy(G_ICMP, 1,
	widenToLargerTypesUnsupportedOtherwise);
	for (auto Ty : {s32, p0})
	setAction({G_ICMP, 1, Ty}, Legal);

	if (!ST.useSoftFloat() && ST.hasVFP2()) {
	for (unsigned BinOp : {G_FADD, G_FSUB, G_FMUL, G_FDIV})
	for (auto Ty : {s32, s64})
	setAction({BinOp, Ty}, Legal);

	setAction({G_LOAD, s64}, Legal);
	setAction({G_STORE, s64}, Legal);

	setAction({G_FCMP, s1}, Legal);
	setAction({G_FCMP, 1, s32}, Legal);
	setAction({G_FCMP, 1, s64}, Legal);

	setAction({G_MERGE_VALUES, s64}, Legal);
	setAction({G_MERGE_VALUES, 1, s32}, Legal);
	setAction({G_UNMERGE_VALUES, s32}, Legal);
	setAction({G_UNMERGE_VALUES, 1, s64}, Legal);
	} else {
	for (unsigned BinOp : {G_FADD, G_FSUB, G_FMUL, G_FDIV})
	for (auto Ty : {s32, s64})
	setAction({BinOp, Ty}, Libcall);

	setAction({G_FCMP, s1}, Legal);
	setAction({G_FCMP, 1, s32}, Custom);
	setAction({G_FCMP, 1, s64}, Custom);

	if (AEABI(ST))
	setFCmpLibcallsAEABI();
	else
	setFCmpLibcallsGNU();
	}

	for (unsigned Op : {G_FREM, G_FPOW})
	for (auto Ty : {s32, s64})
	setAction({Op, Ty}, Libcall);

	computeTables();
	}

	void ARMLegalizerInfo::setFCmpLibcallsAEABI() {
	// FCMP_TRUE and FCMP_FALSE don't need libcalls, they should be
	// default-initialized.
	FCmp32Libcalls.resize(CmpInst::LAST_FCMP_PREDICATE + 1);
	FCmp32Libcalls[CmpInst::FCMP_OEQ] = {
	{RTLIB::OEQ_F32, CmpInst::BAD_ICMP_PREDICATE}};
	FCmp32Libcalls[CmpInst::FCMP_OGE] = {
	{RTLIB::OGE_F32, CmpInst::BAD_ICMP_PREDICATE}};
	FCmp32Libcalls[CmpInst::FCMP_OGT] = {
	{RTLIB::OGT_F32, CmpInst::BAD_ICMP_PREDICATE}};
	FCmp32Libcalls[CmpInst::FCMP_OLE] = {
	{RTLIB::OLE_F32, CmpInst::BAD_ICMP_PREDICATE}};
	FCmp32Libcalls[CmpInst::FCMP_OLT] = {
	{RTLIB::OLT_F32, CmpInst::BAD_ICMP_PREDICATE}};
	FCmp32Libcalls[CmpInst::FCMP_ORD] = {{RTLIB::O_F32, CmpInst::ICMP_EQ}};
	FCmp32Libcalls[CmpInst::FCMP_UGE] = {{RTLIB::OLT_F32, CmpInst::ICMP_EQ}};
	FCmp32Libcalls[CmpInst::FCMP_UGT] = {{RTLIB::OLE_F32, CmpInst::ICMP_EQ}};
	FCmp32Libcalls[CmpInst::FCMP_ULE] = {{RTLIB::OGT_F32, CmpInst::ICMP_EQ}};
	FCmp32Libcalls[CmpInst::FCMP_ULT] = {{RTLIB::OGE_F32, CmpInst::ICMP_EQ}};
	FCmp32Libcalls[CmpInst::FCMP_UNE] = {{RTLIB::UNE_F32, CmpInst::ICMP_EQ}};
	FCmp32Libcalls[CmpInst::FCMP_UNO] = {
	{RTLIB::UO_F32, CmpInst::BAD_ICMP_PREDICATE}};
	FCmp32Libcalls[CmpInst::FCMP_ONE] = {
	{RTLIB::OGT_F32, CmpInst::BAD_ICMP_PREDICATE},
	{RTLIB::OLT_F32, CmpInst::BAD_ICMP_PREDICATE}};
	FCmp32Libcalls[CmpInst::FCMP_UEQ] = {
	{RTLIB::OEQ_F32, CmpInst::BAD_ICMP_PREDICATE},
	{RTLIB::UO_F32, CmpInst::BAD_ICMP_PREDICATE}};

	FCmp64Libcalls.resize(CmpInst::LAST_FCMP_PREDICATE + 1);
	FCmp64Libcalls[CmpInst::FCMP_OEQ] = {
	{RTLIB::OEQ_F64, CmpInst::BAD_ICMP_PREDICATE}};
	FCmp64Libcalls[CmpInst::FCMP_OGE] = {
	{RTLIB::OGE_F64, CmpInst::BAD_ICMP_PREDICATE}};
	FCmp64Libcalls[CmpInst::FCMP_OGT] = {
	{RTLIB::OGT_F64, CmpInst::BAD_ICMP_PREDICATE}};
	FCmp64Libcalls[CmpInst::FCMP_OLE] = {
	{RTLIB::OLE_F64, CmpInst::BAD_ICMP_PREDICATE}};
	FCmp64Libcalls[CmpInst::FCMP_OLT] = {
	{RTLIB::OLT_F64, CmpInst::BAD_ICMP_PREDICATE}};
	FCmp64Libcalls[CmpInst::FCMP_ORD] = {{RTLIB::O_F64, CmpInst::ICMP_EQ}};
	FCmp64Libcalls[CmpInst::FCMP_UGE] = {{RTLIB::OLT_F64, CmpInst::ICMP_EQ}};
	FCmp64Libcalls[CmpInst::FCMP_UGT] = {{RTLIB::OLE_F64, CmpInst::ICMP_EQ}};
	FCmp64Libcalls[CmpInst::FCMP_ULE] = {{RTLIB::OGT_F64, CmpInst::ICMP_EQ}};
	FCmp64Libcalls[CmpInst::FCMP_ULT] = {{RTLIB::OGE_F64, CmpInst::ICMP_EQ}};
	FCmp64Libcalls[CmpInst::FCMP_UNE] = {{RTLIB::UNE_F64, CmpInst::ICMP_EQ}};
	FCmp64Libcalls[CmpInst::FCMP_UNO] = {
	{RTLIB::UO_F64, CmpInst::BAD_ICMP_PREDICATE}};
	FCmp64Libcalls[CmpInst::FCMP_ONE] = {
	{RTLIB::OGT_F64, CmpInst::BAD_ICMP_PREDICATE},
	{RTLIB::OLT_F64, CmpInst::BAD_ICMP_PREDICATE}};
	FCmp64Libcalls[CmpInst::FCMP_UEQ] = {
	{RTLIB::OEQ_F64, CmpInst::BAD_ICMP_PREDICATE},
	{RTLIB::UO_F64, CmpInst::BAD_ICMP_PREDICATE}};
	}

	void ARMLegalizerInfo::setFCmpLibcallsGNU() {
	// FCMP_TRUE and FCMP_FALSE don't need libcalls, they should be
	// default-initialized.
	FCmp32Libcalls.resize(CmpInst::LAST_FCMP_PREDICATE + 1);
	FCmp32Libcalls[CmpInst::FCMP_OEQ] = {{RTLIB::OEQ_F32, CmpInst::ICMP_EQ}};
	FCmp32Libcalls[CmpInst::FCMP_OGE] = {{RTLIB::OGE_F32, CmpInst::ICMP_SGE}};
	FCmp32Libcalls[CmpInst::FCMP_OGT] = {{RTLIB::OGT_F32, CmpInst::ICMP_SGT}};
	FCmp32Libcalls[CmpInst::FCMP_OLE] = {{RTLIB::OLE_F32, CmpInst::ICMP_SLE}};
	FCmp32Libcalls[CmpInst::FCMP_OLT] = {{RTLIB::OLT_F32, CmpInst::ICMP_SLT}};
	FCmp32Libcalls[CmpInst::FCMP_ORD] = {{RTLIB::O_F32, CmpInst::ICMP_EQ}};
	FCmp32Libcalls[CmpInst::FCMP_UGE] = {{RTLIB::OLT_F32, CmpInst::ICMP_SGE}};
	FCmp32Libcalls[CmpInst::FCMP_UGT] = {{RTLIB::OLE_F32, CmpInst::ICMP_SGT}};
	FCmp32Libcalls[CmpInst::FCMP_ULE] = {{RTLIB::OGT_F32, CmpInst::ICMP_SLE}};
	FCmp32Libcalls[CmpInst::FCMP_ULT] = {{RTLIB::OGE_F32, CmpInst::ICMP_SLT}};
	FCmp32Libcalls[CmpInst::FCMP_UNE] = {{RTLIB::UNE_F32, CmpInst::ICMP_NE}};
	FCmp32Libcalls[CmpInst::FCMP_UNO] = {{RTLIB::UO_F32, CmpInst::ICMP_NE}};
	FCmp32Libcalls[CmpInst::FCMP_ONE] = {{RTLIB::OGT_F32, CmpInst::ICMP_SGT},
	{RTLIB::OLT_F32, CmpInst::ICMP_SLT}};
	FCmp32Libcalls[CmpInst::FCMP_UEQ] = {{RTLIB::OEQ_F32, CmpInst::ICMP_EQ},
	{RTLIB::UO_F32, CmpInst::ICMP_NE}};

	FCmp64Libcalls.resize(CmpInst::LAST_FCMP_PREDICATE + 1);
	FCmp64Libcalls[CmpInst::FCMP_OEQ] = {{RTLIB::OEQ_F64, CmpInst::ICMP_EQ}};
	FCmp64Libcalls[CmpInst::FCMP_OGE] = {{RTLIB::OGE_F64, CmpInst::ICMP_SGE}};
	FCmp64Libcalls[CmpInst::FCMP_OGT] = {{RTLIB::OGT_F64, CmpInst::ICMP_SGT}};
	FCmp64Libcalls[CmpInst::FCMP_OLE] = {{RTLIB::OLE_F64, CmpInst::ICMP_SLE}};
	FCmp64Libcalls[CmpInst::FCMP_OLT] = {{RTLIB::OLT_F64, CmpInst::ICMP_SLT}};
	FCmp64Libcalls[CmpInst::FCMP_ORD] = {{RTLIB::O_F64, CmpInst::ICMP_EQ}};
	FCmp64Libcalls[CmpInst::FCMP_UGE] = {{RTLIB::OLT_F64, CmpInst::ICMP_SGE}};
	FCmp64Libcalls[CmpInst::FCMP_UGT] = {{RTLIB::OLE_F64, CmpInst::ICMP_SGT}};
	FCmp64Libcalls[CmpInst::FCMP_ULE] = {{RTLIB::OGT_F64, CmpInst::ICMP_SLE}};
	FCmp64Libcalls[CmpInst::FCMP_ULT] = {{RTLIB::OGE_F64, CmpInst::ICMP_SLT}};
	FCmp64Libcalls[CmpInst::FCMP_UNE] = {{RTLIB::UNE_F64, CmpInst::ICMP_NE}};
	FCmp64Libcalls[CmpInst::FCMP_UNO] = {{RTLIB::UO_F64, CmpInst::ICMP_NE}};
	FCmp64Libcalls[CmpInst::FCMP_ONE] = {{RTLIB::OGT_F64, CmpInst::ICMP_SGT},
	{RTLIB::OLT_F64, CmpInst::ICMP_SLT}};
	FCmp64Libcalls[CmpInst::FCMP_UEQ] = {{RTLIB::OEQ_F64, CmpInst::ICMP_EQ},
	{RTLIB::UO_F64, CmpInst::ICMP_NE}};
	}

	ARMLegalizerInfo::FCmpLibcallsList
	ARMLegalizerInfo::getFCmpLibcalls(CmpInst::Predicate Predicate,
	unsigned Size) const {
	assert(CmpInst::isFPPredicate(Predicate) && "Unsupported FCmp predicate");
	if (Size == 32)
	return FCmp32Libcalls[Predicate];
	if (Size == 64)
	return FCmp64Libcalls[Predicate];
	llvm_unreachable("Unsupported size for FCmp predicate");
	}

	bool ARMLegalizerInfo::legalizeCustom(MachineInstr &MI,
	MachineRegisterInfo &MRI,
	MachineIRBuilder &MIRBuilder) const {
	using namespace TargetOpcode;

	MIRBuilder.setInstr(MI);

	switch (MI.getOpcode()) {
	default:
	return false;
	case G_SREM:
	case G_UREM: {
	unsigned OriginalResult = MI.getOperand(0).getReg();
	auto Size = MRI.getType(OriginalResult).getSizeInBits();
	if (Size != 32)
	return false;

	auto Libcall =
	MI.getOpcode() == G_SREM ? RTLIB::SDIVREM_I32 : RTLIB::UDIVREM_I32;

	// Our divmod libcalls return a struct containing the quotient and the
	// remainder. We need to create a virtual register for it.
	auto &Ctx = MIRBuilder.getMF().getFunction().getContext();
	Type *ArgTy = Type::getInt32Ty(Ctx);
	StructType RetTy = StructType::get(Ctx, {ArgTy, ArgTy}, / Packed */ true);
	auto RetVal = MRI.createGenericVirtualRegister(
	getLLTForType(*RetTy, MIRBuilder.getMF().getDataLayout()));

	auto Status = createLibcall(MIRBuilder, Libcall, {RetVal, RetTy},
	{{MI.getOperand(1).getReg(), ArgTy},
	{MI.getOperand(2).getReg(), ArgTy}});
	if (Status != LegalizerHelper::Legalized)
	return false;

	// The remainder is the second result of divmod. Split the return value into
	// a new, unused register for the quotient and the destination of the
	// original instruction for the remainder.
	MIRBuilder.buildUnmerge(
	{MRI.createGenericVirtualRegister(LLT::scalar(32)), OriginalResult},
	RetVal);
	break;
	}
	case G_FCMP: {
	assert(MRI.getType(MI.getOperand(2).getReg()) ==
	MRI.getType(MI.getOperand(3).getReg()) &&
	"Mismatched operands for G_FCMP");
	auto OpSize = MRI.getType(MI.getOperand(2).getReg()).getSizeInBits();

	auto OriginalResult = MI.getOperand(0).getReg();
	auto Predicate =
	static_cast<CmpInst::Predicate>(MI.getOperand(1).getPredicate());
	auto Libcalls = getFCmpLibcalls(Predicate, OpSize);

	if (Libcalls.empty()) {
	assert((Predicate == CmpInst::FCMP_TRUE \|\|
	Predicate == CmpInst::FCMP_FALSE) &&
	"Predicate needs libcalls, but none specified");
	MIRBuilder.buildConstant(OriginalResult,
	Predicate == CmpInst::FCMP_TRUE ? 1 : 0);
	MI.eraseFromParent();
	return true;
	}

	auto &Ctx = MIRBuilder.getMF().getFunction().getContext();
	assert((OpSize == 32 \|\| OpSize == 64) && "Unsupported operand size");
	auto *ArgTy = OpSize == 32 ? Type::getFloatTy(Ctx) : Type::getDoubleTy(Ctx);
	auto *RetTy = Type::getInt32Ty(Ctx);

	SmallVector<unsigned, 2> Results;
	for (auto Libcall : Libcalls) {
	auto LibcallResult = MRI.createGenericVirtualRegister(LLT::scalar(32));
	auto Status =
	createLibcall(MIRBuilder, Libcall.LibcallID, {LibcallResult, RetTy},
	{{MI.getOperand(2).getReg(), ArgTy},
	{MI.getOperand(3).getReg(), ArgTy}});

	if (Status != LegalizerHelper::Legalized)
	return false;

	auto ProcessedResult =
	Libcalls.size() == 1
	? OriginalResult
	: MRI.createGenericVirtualRegister(MRI.getType(OriginalResult));

	// We have a result, but we need to transform it into a proper 1-bit 0 or
	// 1, taking into account the different peculiarities of the values
	// returned by the comparison functions.
	CmpInst::Predicate ResultPred = Libcall.Predicate;
	if (ResultPred == CmpInst::BAD_ICMP_PREDICATE) {
	// We have a nice 0 or 1, and we just need to truncate it back to 1 bit
	// to keep the types consistent.
	MIRBuilder.buildTrunc(ProcessedResult, LibcallResult);
	} else {
	// We need to compare against 0.
	assert(CmpInst::isIntPredicate(ResultPred) && "Unsupported predicate");
	auto Zero = MRI.createGenericVirtualRegister(LLT::scalar(32));
	MIRBuilder.buildConstant(Zero, 0);
	MIRBuilder.buildICmp(ResultPred, ProcessedResult, LibcallResult, Zero);
	}
	Results.push_back(ProcessedResult);
	}

	if (Results.size() != 1) {
	assert(Results.size() == 2 && "Unexpected number of results");
	MIRBuilder.buildOr(OriginalResult, Results[0], Results[1]);
	}
	break;
	}
	}

	MI.eraseFromParent();
	return true;
	}