lib/Target/Mips/MipsCCState.cpp

   1 //===---- MipsCCState.cpp - CCState with Mips specific extensions ---------===//
   2 //
   3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
   4 // See https://llvm.org/LICENSE.txt for license information.
   5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
   6 //
   7 //===----------------------------------------------------------------------===//
   8
   9 #include "MipsCCState.h"
  10 #include "MipsSubtarget.h"
  11 #include "llvm/IR/Module.h"
  12
  13 using namespace llvm;
  14
  15 /// This function returns true if CallSym is a long double emulation routine.
  16 static bool isF128SoftLibCall(const char *CallSym) {
  17   const char *const LibCalls[] = {
  18       "__addtf3",      "__divtf3",     "__eqtf2",       "__extenddftf2",
  19       "__extendsftf2", "__fixtfdi",    "__fixtfsi",     "__fixtfti",
  20       "__fixunstfdi",  "__fixunstfsi", "__fixunstfti",  "__floatditf",
  21       "__floatsitf",   "__floattitf",  "__floatunditf", "__floatunsitf",
  22       "__floatuntitf", "__getf2",      "__gttf2",       "__letf2",
  23       "__lttf2",       "__multf3",     "__netf2",       "__powitf2",
  24       "__subtf3",      "__trunctfdf2", "__trunctfsf2",  "__unordtf2",
  25       "ceill",         "copysignl",    "cosl",          "exp2l",
  26       "expl",          "floorl",       "fmal",          "fmaxl",
  27       "fmodl",         "log10l",       "log2l",         "logl",
  28       "nearbyintl",    "powl",         "rintl",         "roundl",
  29       "sinl",          "sqrtl",        "truncl"};
  30
  31   // Check that LibCalls is sorted alphabetically.
  32   auto Comp = [](const char *S1, const char *S2) { return strcmp(S1, S2) < 0; };
  33   assert(std::is_sorted(std::begin(LibCalls), std::end(LibCalls), Comp));
  34   return std::binary_search(std::begin(LibCalls), std::end(LibCalls),
  35                             CallSym, Comp);
  36 }
  37
  38 /// This function returns true if Ty is fp128, {f128} or i128 which was
  39 /// originally a fp128.
  40 static bool originalTypeIsF128(const Type *Ty, const char *Func) {
  41   if (Ty->isFP128Ty())
  42     return true;
  43
  44   if (Ty->isStructTy() && Ty->getStructNumElements() == 1 &&
  45       Ty->getStructElementType(0)->isFP128Ty())
  46     return true;
  47
  48   // If the Ty is i128 and the function being called is a long double emulation
  49   // routine, then the original type is f128.
  50   return (Func && Ty->isIntegerTy(128) && isF128SoftLibCall(Func));
  51 }
  52
  53 /// Return true if the original type was vXfXX.
  54 static bool originalEVTTypeIsVectorFloat(EVT Ty) {
  55   if (Ty.isVector() && Ty.getVectorElementType().isFloatingPoint())
  56     return true;
  57
  58   return false;
  59 }
  60
  61 /// Return true if the original type was vXfXX / vXfXX.
  62 static bool originalTypeIsVectorFloat(const Type * Ty) {
  63   if (Ty->isVectorTy() && Ty->isFPOrFPVectorTy())
  64     return true;
  65
  66   return false;
  67 }
  68
  69 MipsCCState::SpecialCallingConvType
  70 MipsCCState::getSpecialCallingConvForCallee(const SDNode *Callee,
  71                                             const MipsSubtarget &Subtarget) {
  72   MipsCCState::SpecialCallingConvType SpecialCallingConv = NoSpecialCallingConv;
  73   if (Subtarget.inMips16HardFloat()) {
  74     if (const GlobalAddressSDNode *G =
  75             dyn_cast<const GlobalAddressSDNode>(Callee)) {
  76       llvm::StringRef Sym = G->getGlobal()->getName();
  77       Function *F = G->getGlobal()->getParent()->getFunction(Sym);
  78       if (F && F->hasFnAttribute("__Mips16RetHelper")) {
  79         SpecialCallingConv = Mips16RetHelperConv;
  80       }
  81     }
  82   }
  83   return SpecialCallingConv;
  84 }
  85
  86 void MipsCCState::PreAnalyzeCallResultForF128(
  87     const SmallVectorImpl<ISD::InputArg> &Ins,
  88     const Type *RetTy, const char *Call) {
  89   for (unsigned i = 0; i < Ins.size(); ++i) {
  90     OriginalArgWasF128.push_back(
  91         originalTypeIsF128(RetTy, Call));
  92     OriginalArgWasFloat.push_back(RetTy->isFloatingPointTy());
  93   }
  94 }
  95
  96 /// Identify lowered values that originated from f128 or float arguments and
  97 /// record this for use by RetCC_MipsN.
  98 void MipsCCState::PreAnalyzeReturnForF128(
  99     const SmallVectorImpl<ISD::OutputArg> &Outs) {
 100   const MachineFunction &MF = getMachineFunction();
 101   for (unsigned i = 0; i < Outs.size(); ++i) {
 102     OriginalArgWasF128.push_back(
 103         originalTypeIsF128(MF.getFunction().getReturnType(), nullptr));
 104     OriginalArgWasFloat.push_back(
 105         MF.getFunction().getReturnType()->isFloatingPointTy());
 106   }
 107 }
 108
 109 /// Identify lower values that originated from vXfXX and record
 110 /// this.
 111 void MipsCCState::PreAnalyzeCallResultForVectorFloat(
 112     const SmallVectorImpl<ISD::InputArg> &Ins, const Type *RetTy) {
 113   for (unsigned i = 0; i < Ins.size(); ++i) {
 114     OriginalRetWasFloatVector.push_back(originalTypeIsVectorFloat(RetTy));
 115   }
 116 }
 117
 118 /// Identify lowered values that originated from vXfXX arguments and record
 119 /// this.
 120 void MipsCCState::PreAnalyzeReturnForVectorFloat(
 121     const SmallVectorImpl<ISD::OutputArg> &Outs) {
 122   for (unsigned i = 0; i < Outs.size(); ++i) {
 123     ISD::OutputArg Out = Outs[i];
 124     OriginalRetWasFloatVector.push_back(
 125         originalEVTTypeIsVectorFloat(Out.ArgVT));
 126   }
 127 }
 128
 129 /// Identify lowered values that originated from f128, float and sret to vXfXX
 130 /// arguments and record this.
 131 void MipsCCState::PreAnalyzeCallOperands(
 132     const SmallVectorImpl<ISD::OutputArg> &Outs,
 133     std::vector<TargetLowering::ArgListEntry> &FuncArgs,
 134     const char *Func) {
 135   for (unsigned i = 0; i < Outs.size(); ++i) {
 136     TargetLowering::ArgListEntry FuncArg = FuncArgs[Outs[i].OrigArgIndex];
 137
 138     OriginalArgWasF128.push_back(originalTypeIsF128(FuncArg.Ty, Func));
 139     OriginalArgWasFloat.push_back(FuncArg.Ty->isFloatingPointTy());
 140     OriginalArgWasFloatVector.push_back(FuncArg.Ty->isVectorTy());
 141     CallOperandIsFixed.push_back(Outs[i].IsFixed);
 142   }
 143 }
 144
 145 /// Identify lowered values that originated from f128, float and vXfXX arguments
 146 /// and record this.
 147 void MipsCCState::PreAnalyzeFormalArgumentsForF128(
 148     const SmallVectorImpl<ISD::InputArg> &Ins) {
 149   const MachineFunction &MF = getMachineFunction();
 150   for (unsigned i = 0; i < Ins.size(); ++i) {
 151     Function::const_arg_iterator FuncArg = MF.getFunction().arg_begin();
 152
 153     // SRet arguments cannot originate from f128 or {f128} returns so we just
 154     // push false. We have to handle this specially since SRet arguments
 155     // aren't mapped to an original argument.
 156     if (Ins[i].Flags.isSRet()) {
 157       OriginalArgWasF128.push_back(false);
 158       OriginalArgWasFloat.push_back(false);
 159       OriginalArgWasFloatVector.push_back(false);
 160       continue;
 161     }
 162
 163     assert(Ins[i].getOrigArgIndex() < MF.getFunction().arg_size());
 164     std::advance(FuncArg, Ins[i].getOrigArgIndex());
 165
 166     OriginalArgWasF128.push_back(
 167         originalTypeIsF128(FuncArg->getType(), nullptr));
 168     OriginalArgWasFloat.push_back(FuncArg->getType()->isFloatingPointTy());
 169
 170     // The MIPS vector ABI exhibits a corner case of sorts or quirk; if the
 171     // first argument is actually an SRet pointer to a vector, then the next
 172     // argument slot is $a2.
 173     OriginalArgWasFloatVector.push_back(FuncArg->getType()->isVectorTy());
 174   }
 175 }