lib/VMCore/AutoUpgrade.cpp

   1 //===-- AutoUpgrade.cpp - Implement auto-upgrade helper functions ---------===//
   2 //
   3 //                     The LLVM Compiler Infrastructure
   4 //
   5 // This file is distributed under the University of Illinois Open Source
   6 // License. See LICENSE.TXT for details.
   7 //
   8 //===----------------------------------------------------------------------===//
   9 //
  10 // This file implements the auto-upgrade helper functions
  11 //
  12 //===----------------------------------------------------------------------===//
  13
  14 #include "llvm/AutoUpgrade.h"
  15 #include "llvm/Constants.h"
  16 #include "llvm/Function.h"
  17 #include "llvm/LLVMContext.h"
  18 #include "llvm/Module.h"
  19 #include "llvm/Instructions.h"
  20 #include "llvm/Intrinsics.h"
  21 #include "llvm/ADT/SmallVector.h"
  22 #include "llvm/Support/ErrorHandling.h"
  23 #include <cstring>
  24 using namespace llvm;
  25
  26
  27 static bool UpgradeIntrinsicFunction1(Function *F, Function *&NewFn) {
  28   assert(F && "Illegal to upgrade a non-existent Function.");
  29
  30   // Get the Function's name.
  31   const std::string& Name = F->getName();
  32
  33   // Convenience
  34   const FunctionType *FTy = F->getFunctionType();
  35
  36   // Quickly eliminate it, if it's not a candidate.
  37   if (Name.length() <= 8 || Name[0] != 'l' || Name[1] != 'l' ||
  38       Name[2] != 'v' || Name[3] != 'm' || Name[4] != '.')
  39     return false;
  40
  41   Module *M = F->getParent();
  42   switch (Name[5]) {
  43   default: break;
  44   case 'a':
  45     // This upgrades the llvm.atomic.lcs, llvm.atomic.las, llvm.atomic.lss,
  46     // and atomics with default address spaces to their new names to their new
  47     // function name (e.g. llvm.atomic.add.i32 => llvm.atomic.add.i32.p0i32)
  48     if (Name.compare(5,7,"atomic.",7) == 0) {
  49       if (Name.compare(12,3,"lcs",3) == 0) {
  50         std::string::size_type delim = Name.find('.',12);
  51         F->setName("llvm.atomic.cmp.swap" + Name.substr(delim) +
  52                    ".p0" + Name.substr(delim+1));
  53         NewFn = F;
  54         return true;
  55       }
  56       else if (Name.compare(12,3,"las",3) == 0) {
  57         std::string::size_type delim = Name.find('.',12);
  58         F->setName("llvm.atomic.load.add"+Name.substr(delim)
  59                    + ".p0" + Name.substr(delim+1));
  60         NewFn = F;
  61         return true;
  62       }
  63       else if (Name.compare(12,3,"lss",3) == 0) {
  64         std::string::size_type delim = Name.find('.',12);
  65         F->setName("llvm.atomic.load.sub"+Name.substr(delim)
  66                    + ".p0" + Name.substr(delim+1));
  67         NewFn = F;
  68         return true;
  69       }
  70       else if (Name.rfind(".p") == std::string::npos) {
  71         // We don't have an address space qualifier so this has be upgraded
  72         // to the new name.  Copy the type name at the end of the intrinsic
  73         // and add to it
  74         std::string::size_type delim = Name.find_last_of('.');
  75         assert(delim != std::string::npos && "can not find type");
  76         F->setName(Name + ".p0" + Name.substr(delim+1));
  77         NewFn = F;
  78         return true;
  79       }
  80     }
  81     break;
  82   case 'b':
  83     //  This upgrades the name of the llvm.bswap intrinsic function to only use
  84     //  a single type name for overloading. We only care about the old format
  85     //  'llvm.bswap.i*.i*', so check for 'bswap.' and then for there being
  86     //  a '.' after 'bswap.'
  87     if (Name.compare(5,6,"bswap.",6) == 0) {
  88       std::string::size_type delim = Name.find('.',11);
  89
  90       if (delim != std::string::npos) {
  91         //  Construct the new name as 'llvm.bswap' + '.i*'
  92         F->setName(Name.substr(0,10)+Name.substr(delim));
  93         NewFn = F;
  94         return true;
  95       }
  96     }
  97     break;
  98
  99   case 'c':
 100     //  We only want to fix the 'llvm.ct*' intrinsics which do not have the
 101     //  correct return type, so we check for the name, and then check if the
 102     //  return type does not match the parameter type.
 103     if ( (Name.compare(5,5,"ctpop",5) == 0 ||
 104           Name.compare(5,4,"ctlz",4) == 0 ||
 105           Name.compare(5,4,"cttz",4) == 0) &&
 106         FTy->getReturnType() != FTy->getParamType(0)) {
 107       //  We first need to change the name of the old (bad) intrinsic, because
 108       //  its type is incorrect, but we cannot overload that name. We
 109       //  arbitrarily unique it here allowing us to construct a correctly named
 110       //  and typed function below.
 111       F->setName("");
 112
 113       //  Now construct the new intrinsic with the correct name and type. We
 114       //  leave the old function around in order to query its type, whatever it
 115       //  may be, and correctly convert up to the new type.
 116       NewFn = cast<Function>(M->getOrInsertFunction(Name,
 117                                                     FTy->getParamType(0),
 118                                                     FTy->getParamType(0),
 119                                                     (Type *)0));
 120       return true;
 121     }
 122     break;
 123
 124   case 'p':
 125     //  This upgrades the llvm.part.select overloaded intrinsic names to only
 126     //  use one type specifier in the name. We only care about the old format
 127     //  'llvm.part.select.i*.i*', and solve as above with bswap.
 128     if (Name.compare(5,12,"part.select.",12) == 0) {
 129       std::string::size_type delim = Name.find('.',17);
 130
 131       if (delim != std::string::npos) {
 132         //  Construct a new name as 'llvm.part.select' + '.i*'
 133         F->setName(Name.substr(0,16)+Name.substr(delim));
 134         NewFn = F;
 135         return true;
 136       }
 137       break;
 138     }
 139
 140     //  This upgrades the llvm.part.set intrinsics similarly as above, however
 141     //  we care about 'llvm.part.set.i*.i*.i*', but only the first two types
 142     //  must match. There is an additional type specifier after these two
 143     //  matching types that we must retain when upgrading.  Thus, we require
 144     //  finding 2 periods, not just one, after the intrinsic name.
 145     if (Name.compare(5,9,"part.set.",9) == 0) {
 146       std::string::size_type delim = Name.find('.',14);
 147
 148       if (delim != std::string::npos &&
 149           Name.find('.',delim+1) != std::string::npos) {
 150         //  Construct a new name as 'llvm.part.select' + '.i*.i*'
 151         F->setName(Name.substr(0,13)+Name.substr(delim));
 152         NewFn = F;
 153         return true;
 154       }
 155       break;
 156     }
 157
 158     break;
 159   case 'x':
 160     // This fixes all MMX shift intrinsic instructions to take a
 161     // v1i64 instead of a v2i32 as the second parameter.
 162     if (Name.compare(5,10,"x86.mmx.ps",10) == 0 &&
 163         (Name.compare(13,4,"psll", 4) == 0 ||
 164          Name.compare(13,4,"psra", 4) == 0 ||
 165          Name.compare(13,4,"psrl", 4) == 0) && Name[17] != 'i') {
 166
 167       const llvm::Type *VT =
 168                         VectorType::get(IntegerType::get(64), 1);
 169
 170       // We don't have to do anything if the parameter already has
 171       // the correct type.
 172       if (FTy->getParamType(1) == VT)
 173         break;
 174
 175       //  We first need to change the name of the old (bad) intrinsic, because
 176       //  its type is incorrect, but we cannot overload that name. We
 177       //  arbitrarily unique it here allowing us to construct a correctly named
 178       //  and typed function below.
 179       F->setName("");
 180
 181       assert(FTy->getNumParams() == 2 && "MMX shift intrinsics take 2 args!");
 182
 183       //  Now construct the new intrinsic with the correct name and type. We
 184       //  leave the old function around in order to query its type, whatever it
 185       //  may be, and correctly convert up to the new type.
 186       NewFn = cast<Function>(M->getOrInsertFunction(Name,
 187                                                     FTy->getReturnType(),
 188                                                     FTy->getParamType(0),
 189                                                     VT,
 190                                                     (Type *)0));
 191       return true;
 192     } else if (Name.compare(5,17,"x86.sse2.loadh.pd",17) == 0 ||
 193                Name.compare(5,17,"x86.sse2.loadl.pd",17) == 0 ||
 194                Name.compare(5,16,"x86.sse2.movl.dq",16) == 0 ||
 195                Name.compare(5,15,"x86.sse2.movs.d",15) == 0 ||
 196                Name.compare(5,16,"x86.sse2.shuf.pd",16) == 0 ||
 197                Name.compare(5,18,"x86.sse2.unpckh.pd",18) == 0 ||
 198                Name.compare(5,18,"x86.sse2.unpckl.pd",18) == 0 ||
 199                Name.compare(5,20,"x86.sse2.punpckh.qdq",20) == 0 ||
 200                Name.compare(5,20,"x86.sse2.punpckl.qdq",20) == 0) {
 201       // Calls to these intrinsics are transformed into ShuffleVector's.
 202       NewFn = 0;
 203       return true;
 204     }
 205
 206     break;
 207   }
 208
 209   //  This may not belong here. This function is effectively being overloaded
 210   //  to both detect an intrinsic which needs upgrading, and to provide the
 211   //  upgraded form of the intrinsic. We should perhaps have two separate
 212   //  functions for this.
 213   return false;
 214 }
 215
 216 bool llvm::UpgradeIntrinsicFunction(Function *F, Function *&NewFn) {
 217   NewFn = 0;
 218   bool Upgraded = UpgradeIntrinsicFunction1(F, NewFn);
 219
 220   // Upgrade intrinsic attributes.  This does not change the function.
 221   if (NewFn)
 222     F = NewFn;
 223   if (unsigned id = F->getIntrinsicID())
 224     F->setAttributes(Intrinsic::getAttributes((Intrinsic::ID)id));
 225   return Upgraded;
 226 }
 227
 228 // UpgradeIntrinsicCall - Upgrade a call to an old intrinsic to be a call the
 229 // upgraded intrinsic. All argument and return casting must be provided in
 230 // order to seamlessly integrate with existing context.
 231 void llvm::UpgradeIntrinsicCall(CallInst *CI, Function *NewFn) {
 232   Function *F = CI->getCalledFunction();
 233
 234   assert(F && "CallInst has no function associated with it.");
 235
 236   if (!NewFn) {
 237     bool isLoadH = false, isLoadL = false, isMovL = false;
 238     bool isMovSD = false, isShufPD = false;
 239     bool isUnpckhPD = false, isUnpcklPD = false;
 240     bool isPunpckhQPD = false, isPunpcklQPD = false;
 241     if (F->getName() == "llvm.x86.sse2.loadh.pd")
 242       isLoadH = true;
 243     else if (F->getName() == "llvm.x86.sse2.loadl.pd")
 244       isLoadL = true;
 245     else if (F->getName() == "llvm.x86.sse2.movl.dq")
 246       isMovL = true;
 247     else if (F->getName() == "llvm.x86.sse2.movs.d")
 248       isMovSD = true;
 249     else if (F->getName() == "llvm.x86.sse2.shuf.pd")
 250       isShufPD = true;
 251     else if (F->getName() == "llvm.x86.sse2.unpckh.pd")
 252       isUnpckhPD = true;
 253     else if (F->getName() == "llvm.x86.sse2.unpckl.pd")
 254       isUnpcklPD = true;
 255     else if (F->getName() ==  "llvm.x86.sse2.punpckh.qdq")
 256       isPunpckhQPD = true;
 257     else if (F->getName() ==  "llvm.x86.sse2.punpckl.qdq")
 258       isPunpcklQPD = true;
 259
 260     if (isLoadH || isLoadL || isMovL || isMovSD || isShufPD ||
 261         isUnpckhPD || isUnpcklPD || isPunpckhQPD || isPunpcklQPD) {
 262       std::vector<Constant*> Idxs;
 263       Value *Op0 = CI->getOperand(1);
 264       ShuffleVectorInst *SI = NULL;
 265       if (isLoadH || isLoadL) {
 266         Value *Op1 = UndefValue::get(Op0->getType());
 267         Value *Addr = new BitCastInst(CI->getOperand(2),
 268                                   PointerType::getUnqual(Type::DoubleTy),
 269                                       "upgraded.", CI);
 270         Value *Load = new LoadInst(Addr, "upgraded.", false, 8, CI);
 271         Value *Idx = ConstantInt::get(Type::Int32Ty, 0);
 272         Op1 = InsertElementInst::Create(Op1, Load, Idx, "upgraded.", CI);
 273
 274         if (isLoadH) {
 275           Idxs.push_back(ConstantInt::get(Type::Int32Ty, 0));
 276           Idxs.push_back(ConstantInt::get(Type::Int32Ty, 2));
 277         } else {
 278           Idxs.push_back(ConstantInt::get(Type::Int32Ty, 2));
 279           Idxs.push_back(ConstantInt::get(Type::Int32Ty, 1));
 280         }
 281         Value *Mask = ConstantVector::get(Idxs);
 282         SI = new ShuffleVectorInst(Op0, Op1, Mask, "upgraded.", CI);
 283       } else if (isMovL) {
 284         Constant *Zero = ConstantInt::get(Type::Int32Ty, 0);
 285         Idxs.push_back(Zero);
 286         Idxs.push_back(Zero);
 287         Idxs.push_back(Zero);
 288         Idxs.push_back(Zero);
 289         Value *ZeroV = ConstantVector::get(Idxs);
 290
 291         Idxs.clear();
 292         Idxs.push_back(ConstantInt::get(Type::Int32Ty, 4));
 293         Idxs.push_back(ConstantInt::get(Type::Int32Ty, 5));
 294         Idxs.push_back(ConstantInt::get(Type::Int32Ty, 2));
 295         Idxs.push_back(ConstantInt::get(Type::Int32Ty, 3));
 296         Value *Mask = ConstantVector::get(Idxs);
 297         SI = new ShuffleVectorInst(ZeroV, Op0, Mask, "upgraded.", CI);
 298       } else if (isMovSD ||
 299                  isUnpckhPD || isUnpcklPD || isPunpckhQPD || isPunpcklQPD) {
 300         Value *Op1 = CI->getOperand(2);
 301         if (isMovSD) {
 302           Idxs.push_back(ConstantInt::get(Type::Int32Ty, 2));
 303           Idxs.push_back(ConstantInt::get(Type::Int32Ty, 1));
 304         } else if (isUnpckhPD || isPunpckhQPD) {
 305           Idxs.push_back(ConstantInt::get(Type::Int32Ty, 1));
 306           Idxs.push_back(ConstantInt::get(Type::Int32Ty, 3));
 307         } else {
 308           Idxs.push_back(ConstantInt::get(Type::Int32Ty, 0));
 309           Idxs.push_back(ConstantInt::get(Type::Int32Ty, 2));
 310         }
 311         Value *Mask = ConstantVector::get(Idxs);
 312         SI = new ShuffleVectorInst(Op0, Op1, Mask, "upgraded.", CI);
 313       } else if (isShufPD) {
 314         Value *Op1 = CI->getOperand(2);
 315         unsigned MaskVal = cast<ConstantInt>(CI->getOperand(3))->getZExtValue();
 316         Idxs.push_back(ConstantInt::get(Type::Int32Ty, MaskVal & 1));
 317         Idxs.push_back(ConstantInt::get(Type::Int32Ty,
 318                                                ((MaskVal >> 1) & 1)+2));
 319         Value *Mask = ConstantVector::get(Idxs);
 320         SI = new ShuffleVectorInst(Op0, Op1, Mask, "upgraded.", CI);
 321       }
 322
 323       assert(SI && "Unexpected!");
 324
 325       // Handle any uses of the old CallInst.
 326       if (!CI->use_empty())
 327         //  Replace all uses of the old call with the new cast which has the
 328         //  correct type.
 329         CI->replaceAllUsesWith(SI);
 330
 331       //  Clean up the old call now that it has been completely upgraded.
 332       CI->eraseFromParent();
 333     } else {
 334       llvm_unreachable("Unknown function for CallInst upgrade.");
 335     }
 336     return;
 337   }
 338
 339   switch (NewFn->getIntrinsicID()) {
 340   default:  llvm_unreachable("Unknown function for CallInst upgrade.");
 341   case Intrinsic::x86_mmx_psll_d:
 342   case Intrinsic::x86_mmx_psll_q:
 343   case Intrinsic::x86_mmx_psll_w:
 344   case Intrinsic::x86_mmx_psra_d:
 345   case Intrinsic::x86_mmx_psra_w:
 346   case Intrinsic::x86_mmx_psrl_d:
 347   case Intrinsic::x86_mmx_psrl_q:
 348   case Intrinsic::x86_mmx_psrl_w: {
 349     Value *Operands[2];
 350
 351     Operands[0] = CI->getOperand(1);
 352
 353     // Cast the second parameter to the correct type.
 354     BitCastInst *BC = new BitCastInst(CI->getOperand(2),
 355                                       NewFn->getFunctionType()->getParamType(1),
 356                                       "upgraded.", CI);
 357     Operands[1] = BC;
 358
 359     //  Construct a new CallInst
 360     CallInst *NewCI = CallInst::Create(NewFn, Operands, Operands+2,
 361                                        "upgraded."+CI->getName(), CI);
 362     NewCI->setTailCall(CI->isTailCall());
 363     NewCI->setCallingConv(CI->getCallingConv());
 364
 365     //  Handle any uses of the old CallInst.
 366     if (!CI->use_empty())
 367       //  Replace all uses of the old call with the new cast which has the
 368       //  correct type.
 369       CI->replaceAllUsesWith(NewCI);
 370
 371     //  Clean up the old call now that it has been completely upgraded.
 372     CI->eraseFromParent();
 373     break;
 374   }
 375   case Intrinsic::ctlz:
 376   case Intrinsic::ctpop:
 377   case Intrinsic::cttz: {
 378     //  Build a small vector of the 1..(N-1) operands, which are the
 379     //  parameters.
 380     SmallVector<Value*, 8> Operands(CI->op_begin()+1, CI->op_end());
 381
 382     //  Construct a new CallInst
 383     CallInst *NewCI = CallInst::Create(NewFn, Operands.begin(), Operands.end(),
 384                                        "upgraded."+CI->getName(), CI);
 385     NewCI->setTailCall(CI->isTailCall());
 386     NewCI->setCallingConv(CI->getCallingConv());
 387
 388     //  Handle any uses of the old CallInst.
 389     if (!CI->use_empty()) {
 390       //  Check for sign extend parameter attributes on the return values.
 391       bool SrcSExt = NewFn->getAttributes().paramHasAttr(0, Attribute::SExt);
 392       bool DestSExt = F->getAttributes().paramHasAttr(0, Attribute::SExt);
 393
 394       //  Construct an appropriate cast from the new return type to the old.
 395       CastInst *RetCast = CastInst::Create(
 396                             CastInst::getCastOpcode(NewCI, SrcSExt,
 397                                                     F->getReturnType(),
 398                                                     DestSExt),
 399                             NewCI, F->getReturnType(),
 400                             NewCI->getName(), CI);
 401       NewCI->moveBefore(RetCast);
 402
 403       //  Replace all uses of the old call with the new cast which has the
 404       //  correct type.
 405       CI->replaceAllUsesWith(RetCast);
 406     }
 407
 408     //  Clean up the old call now that it has been completely upgraded.
 409     CI->eraseFromParent();
 410   }
 411   break;
 412   }
 413 }
 414
 415 // This tests each Function to determine if it needs upgrading. When we find
 416 // one we are interested in, we then upgrade all calls to reflect the new
 417 // function.
 418 void llvm::UpgradeCallsToIntrinsic(Function* F) {
 419   assert(F && "Illegal attempt to upgrade a non-existent intrinsic.");
 420
 421   // Upgrade the function and check if it is a totaly new function.
 422   Function* NewFn;
 423   if (UpgradeIntrinsicFunction(F, NewFn)) {
 424     if (NewFn != F) {
 425       // Replace all uses to the old function with the new one if necessary.
 426       for (Value::use_iterator UI = F->use_begin(), UE = F->use_end();
 427            UI != UE; ) {
 428         if (CallInst* CI = dyn_cast<CallInst>(*UI++))
 429           UpgradeIntrinsicCall(CI, NewFn);
 430       }
 431       // Remove old function, no longer used, from the module.
 432       F->eraseFromParent();
 433     }
 434   }
 435 }