1 //===-- AutoUpgrade.cpp - Implement auto-upgrade helper functions ---------===//
3 // The LLVM Compiler Infrastructure
5 // This file was developed by Chandler Carruth and is distributed under the
6 // University of Illinois Open Source License. See LICENSE.TXT for details.
8 //===----------------------------------------------------------------------===//
10 // This file implements the auto-upgrade helper functions
12 //===----------------------------------------------------------------------===//
14 #include "llvm/AutoUpgrade.h"
15 #include "llvm/Constants.h"
16 #include "llvm/Function.h"
17 #include "llvm/Module.h"
18 #include "llvm/Instructions.h"
19 #include "llvm/ParameterAttributes.h"
20 #include "llvm/Intrinsics.h"
24 static Function* UpgradeIntrinsicFunction1(Function *F) {
25 assert(F && "Illegal to upgrade a non-existent Function.");
27 // Get the Function's name.
28 const std::string& Name = F->getName();
31 const FunctionType *FTy = F->getFunctionType();
33 // Quickly eliminate it, if it's not a candidate.
34 if (Name.length() <= 8 || Name[0] != 'l' || Name[1] != 'l' ||
35 Name[2] != 'v' || Name[3] != 'm' || Name[4] != '.')
38 Module *M = F->getParent();
42 // This upgrades the name of the llvm.bswap intrinsic function to only use
43 // a single type name for overloading. We only care about the old format
44 // 'llvm.bswap.i*.i*', so check for 'bswap.' and then for there being
45 // a '.' after 'bswap.'
46 if (Name.compare(5,6,"bswap.",6) == 0) {
47 std::string::size_type delim = Name.find('.',11);
49 if (delim != std::string::npos) {
50 // Construct the new name as 'llvm.bswap' + '.i*'
51 F->setName(Name.substr(0,10)+Name.substr(delim));
58 // We only want to fix the 'llvm.ct*' intrinsics which do not have the
59 // correct return type, so we check for the name, and then check if the
60 // return type does not match the parameter type.
61 if ( (Name.compare(5,5,"ctpop",5) == 0 ||
62 Name.compare(5,4,"ctlz",4) == 0 ||
63 Name.compare(5,4,"cttz",4) == 0) &&
64 FTy->getReturnType() != FTy->getParamType(0)) {
65 // We first need to change the name of the old (bad) intrinsic, because
66 // its type is incorrect, but we cannot overload that name. We
67 // arbitrarily unique it here allowing us to construct a correctly named
68 // and typed function below.
71 // Now construct the new intrinsic with the correct name and type. We
72 // leave the old function around in order to query its type, whatever it
73 // may be, and correctly convert up to the new type.
74 return cast<Function>(M->getOrInsertFunction(Name,
82 // This upgrades the llvm.part.select overloaded intrinsic names to only
83 // use one type specifier in the name. We only care about the old format
84 // 'llvm.part.select.i*.i*', and solve as above with bswap.
85 if (Name.compare(5,12,"part.select.",12) == 0) {
86 std::string::size_type delim = Name.find('.',17);
88 if (delim != std::string::npos) {
89 // Construct a new name as 'llvm.part.select' + '.i*'
90 F->setName(Name.substr(0,16)+Name.substr(delim));
96 // This upgrades the llvm.part.set intrinsics similarly as above, however
97 // we care about 'llvm.part.set.i*.i*.i*', but only the first two types
98 // must match. There is an additional type specifier after these two
99 // matching types that we must retain when upgrading. Thus, we require
100 // finding 2 periods, not just one, after the intrinsic name.
101 if (Name.compare(5,9,"part.set.",9) == 0) {
102 std::string::size_type delim = Name.find('.',14);
104 if (delim != std::string::npos &&
105 Name.find('.',delim+1) != std::string::npos) {
106 // Construct a new name as 'llvm.part.select' + '.i*.i*'
107 F->setName(Name.substr(0,13)+Name.substr(delim));
115 // This fixes all MMX shift intrinsic instructions to take a
116 // v1i64 instead of a v2i32 as the second parameter.
117 if (Name.compare(5,10,"x86.mmx.ps",10) == 0 &&
118 (Name.compare(13,4,"psll", 4) == 0 ||
119 Name.compare(13,4,"psra", 4) == 0 ||
120 Name.compare(13,4,"psrl", 4) == 0)) {
122 const llvm::Type *VT = VectorType::get(IntegerType::get(64), 1);
124 // We don't have to do anything if the parameter already has
126 if (FTy->getParamType(1) == VT)
129 // We first need to change the name of the old (bad) intrinsic, because
130 // its type is incorrect, but we cannot overload that name. We
131 // arbitrarily unique it here allowing us to construct a correctly named
132 // and typed function below.
135 assert(FTy->getNumParams() == 2 && "MMX shift intrinsics take 2 args!");
137 // Now construct the new intrinsic with the correct name and type. We
138 // leave the old function around in order to query its type, whatever it
139 // may be, and correctly convert up to the new type.
140 return cast<Function>(M->getOrInsertFunction(Name,
141 FTy->getReturnType(),
142 FTy->getParamType(0),
149 // This may not belong here. This function is effectively being overloaded
150 // to both detect an intrinsic which needs upgrading, and to provide the
151 // upgraded form of the intrinsic. We should perhaps have two separate
152 // functions for this.
156 Function* llvm::UpgradeIntrinsicFunction(Function *F) {
157 Function *Upgraded = UpgradeIntrinsicFunction1(F);
159 // Upgrade intrinsic attributes. This does not change the function.
162 if (unsigned id = F->getIntrinsicID(true))
163 F->setParamAttrs(Intrinsic::getParamAttrs((Intrinsic::ID)id));
167 // UpgradeIntrinsicCall - Upgrade a call to an old intrinsic to be a call the
168 // upgraded intrinsic. All argument and return casting must be provided in
169 // order to seamlessly integrate with existing context.
170 void llvm::UpgradeIntrinsicCall(CallInst *CI, Function *NewFn) {
171 assert(NewFn && "Cannot upgrade an intrinsic call without a new function.");
173 Function *F = CI->getCalledFunction();
174 assert(F && "CallInst has no function associated with it.");
176 switch(NewFn->getIntrinsicID()) {
177 default: assert(0 && "Unknown function for CallInst upgrade.");
178 case Intrinsic::x86_mmx_psll_d:
179 case Intrinsic::x86_mmx_psll_q:
180 case Intrinsic::x86_mmx_psll_w:
181 case Intrinsic::x86_mmx_psra_d:
182 case Intrinsic::x86_mmx_psra_w:
183 case Intrinsic::x86_mmx_psrl_d:
184 case Intrinsic::x86_mmx_psrl_q:
185 case Intrinsic::x86_mmx_psrl_w: {
186 SmallVector<Value*, 2> Operands;
188 Operands.push_back(CI->getOperand(1));
190 // Cast the second parameter to the correct type.
191 BitCastInst *BC = new BitCastInst(CI->getOperand(2),
192 NewFn->getFunctionType()->getParamType(1),
194 Operands.push_back(BC);
196 // Construct a new CallInst
197 CallInst *NewCI = new CallInst(NewFn, Operands.begin(), Operands.end(),
198 "upgraded."+CI->getName(), CI);
199 NewCI->setTailCall(CI->isTailCall());
200 NewCI->setCallingConv(CI->getCallingConv());
202 // Handle any uses of the old CallInst.
203 if (!CI->use_empty())
204 // Replace all uses of the old call with the new cast which has the
206 CI->replaceAllUsesWith(NewCI);
208 // Clean up the old call now that it has been completely upgraded.
209 CI->eraseFromParent();
212 case Intrinsic::ctlz:
213 case Intrinsic::ctpop:
214 case Intrinsic::cttz:
215 // Build a small vector of the 1..(N-1) operands, which are the
217 SmallVector<Value*, 8> Operands(CI->op_begin()+1, CI->op_end());
219 // Construct a new CallInst
220 CallInst *NewCI = new CallInst(NewFn, Operands.begin(), Operands.end(),
221 "upgraded."+CI->getName(), CI);
222 NewCI->setTailCall(CI->isTailCall());
223 NewCI->setCallingConv(CI->getCallingConv());
225 // Handle any uses of the old CallInst.
226 if (!CI->use_empty()) {
227 // Check for sign extend parameter attributes on the return values.
228 bool SrcSExt = NewFn->getParamAttrs() &&
229 NewFn->getParamAttrs()->paramHasAttr(0,ParamAttr::SExt);
230 bool DestSExt = F->getParamAttrs() &&
231 F->getParamAttrs()->paramHasAttr(0,ParamAttr::SExt);
233 // Construct an appropriate cast from the new return type to the old.
234 CastInst *RetCast = CastInst::create(
235 CastInst::getCastOpcode(NewCI, SrcSExt,
238 NewCI, F->getReturnType(),
239 NewCI->getName(), CI);
240 NewCI->moveBefore(RetCast);
242 // Replace all uses of the old call with the new cast which has the
244 CI->replaceAllUsesWith(RetCast);
247 // Clean up the old call now that it has been completely upgraded.
248 CI->eraseFromParent();
253 // This tests each Function to determine if it needs upgrading. When we find
254 // one we are interested in, we then upgrade all calls to reflect the new
256 void llvm::UpgradeCallsToIntrinsic(Function* F) {
257 assert(F && "Illegal attempt to upgrade a non-existent intrinsic.");
259 // Upgrade the function and check if it is a totaly new function.
260 if (Function* NewFn = UpgradeIntrinsicFunction(F)) {
262 // Replace all uses to the old function with the new one if necessary.
263 for (Value::use_iterator UI = F->use_begin(), UE = F->use_end();
265 if (CallInst* CI = dyn_cast<CallInst>(*UI++))
266 UpgradeIntrinsicCall(CI, NewFn);
268 // Remove old function, no longer used, from the module.
269 F->eraseFromParent();