llvm-mirror/lib/VMCore/AutoUpgrade.cpp
Nuno Lopes e8880a9916 change the objectsize intrinsic signature: add a 3rd parameter to denote the maximum runtime performance penalty that the user is willing to accept.
This commit only adds the parameter. Code taking advantage of it will follow.

llvm-svn: 156473
2012-05-09 15:52:43 +00:00

256 lines
8.9 KiB
C++

//===-- AutoUpgrade.cpp - Implement auto-upgrade helper functions ---------===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This file implements the auto-upgrade helper functions
//
//===----------------------------------------------------------------------===//
#include "llvm/AutoUpgrade.h"
#include "llvm/Constants.h"
#include "llvm/Function.h"
#include "llvm/Instruction.h"
#include "llvm/LLVMContext.h"
#include "llvm/Module.h"
#include "llvm/IntrinsicInst.h"
#include "llvm/Support/CallSite.h"
#include "llvm/Support/CFG.h"
#include "llvm/Support/ErrorHandling.h"
#include "llvm/Support/IRBuilder.h"
#include <cstring>
using namespace llvm;
static bool UpgradeIntrinsicFunction1(Function *F, Function *&NewFn) {
assert(F && "Illegal to upgrade a non-existent Function.");
// Quickly eliminate it, if it's not a candidate.
StringRef Name = F->getName();
if (Name.size() <= 8 || !Name.startswith("llvm."))
return false;
Name = Name.substr(5); // Strip off "llvm."
switch (Name[0]) {
default: break;
case 'c': {
if (Name.startswith("ctlz.") && F->arg_size() == 1) {
F->setName(Name + ".old");
NewFn = Intrinsic::getDeclaration(F->getParent(), Intrinsic::ctlz,
F->arg_begin()->getType());
return true;
}
if (Name.startswith("cttz.") && F->arg_size() == 1) {
F->setName(Name + ".old");
NewFn = Intrinsic::getDeclaration(F->getParent(), Intrinsic::cttz,
F->arg_begin()->getType());
return true;
}
break;
}
case 'o': {
// FIXME: remove in LLVM 3.3
if (Name.startswith("objectsize.") && F->arg_size() == 2) {
Type *Tys[] = {F->getReturnType(),
F->arg_begin()->getType(),
Type::getInt1Ty(F->getContext()),
Type::getInt32Ty(F->getContext())};
NewFn = Intrinsic::getDeclaration(F->getParent(), Intrinsic::objectsize,
Tys);
NewFn->takeName(F);
return true;
}
break;
}
case 'x': {
if (Name.startswith("x86.sse2.pcmpeq.") ||
Name.startswith("x86.sse2.pcmpgt.") ||
Name.startswith("x86.avx2.pcmpeq.") ||
Name.startswith("x86.avx2.pcmpgt.") ||
Name.startswith("x86.avx.vpermil.") ||
Name == "x86.avx.movnt.dq.256" ||
Name == "x86.avx.movnt.pd.256" ||
Name == "x86.avx.movnt.ps.256") {
NewFn = 0;
return true;
}
break;
}
}
// This may not belong here. This function is effectively being overloaded
// to both detect an intrinsic which needs upgrading, and to provide the
// upgraded form of the intrinsic. We should perhaps have two separate
// functions for this.
return false;
}
bool llvm::UpgradeIntrinsicFunction(Function *F, Function *&NewFn) {
NewFn = 0;
bool Upgraded = UpgradeIntrinsicFunction1(F, NewFn);
// Upgrade intrinsic attributes. This does not change the function.
if (NewFn)
F = NewFn;
if (unsigned id = F->getIntrinsicID())
F->setAttributes(Intrinsic::getAttributes((Intrinsic::ID)id));
return Upgraded;
}
bool llvm::UpgradeGlobalVariable(GlobalVariable *GV) {
// Nothing to do yet.
return false;
}
// UpgradeIntrinsicCall - Upgrade a call to an old intrinsic to be a call the
// upgraded intrinsic. All argument and return casting must be provided in
// order to seamlessly integrate with existing context.
void llvm::UpgradeIntrinsicCall(CallInst *CI, Function *NewFn) {
Function *F = CI->getCalledFunction();
LLVMContext &C = CI->getContext();
IRBuilder<> Builder(C);
Builder.SetInsertPoint(CI->getParent(), CI);
assert(F && "Intrinsic call is not direct?");
if (!NewFn) {
// Get the Function's name.
StringRef Name = F->getName();
Value *Rep;
// Upgrade packed integer vector compares intrinsics to compare instructions
if (Name.startswith("llvm.x86.sse2.pcmpeq.") ||
Name.startswith("llvm.x86.avx2.pcmpeq.")) {
Rep = Builder.CreateICmpEQ(CI->getArgOperand(0), CI->getArgOperand(1),
"pcmpeq");
// need to sign extend since icmp returns vector of i1
Rep = Builder.CreateSExt(Rep, CI->getType(), "");
} else if (Name.startswith("llvm.x86.sse2.pcmpgt.") ||
Name.startswith("llvm.x86.avx2.pcmpgt.")) {
Rep = Builder.CreateICmpSGT(CI->getArgOperand(0), CI->getArgOperand(1),
"pcmpgt");
// need to sign extend since icmp returns vector of i1
Rep = Builder.CreateSExt(Rep, CI->getType(), "");
} else if (Name == "llvm.x86.avx.movnt.dq.256" ||
Name == "llvm.x86.avx.movnt.ps.256" ||
Name == "llvm.x86.avx.movnt.pd.256") {
IRBuilder<> Builder(C);
Builder.SetInsertPoint(CI->getParent(), CI);
Module *M = F->getParent();
SmallVector<Value *, 1> Elts;
Elts.push_back(ConstantInt::get(Type::getInt32Ty(C), 1));
MDNode *Node = MDNode::get(C, Elts);
Value *Arg0 = CI->getArgOperand(0);
Value *Arg1 = CI->getArgOperand(1);
// Convert the type of the pointer to a pointer to the stored type.
Value *BC = Builder.CreateBitCast(Arg0,
PointerType::getUnqual(Arg1->getType()),
"cast");
StoreInst *SI = Builder.CreateStore(Arg1, BC);
SI->setMetadata(M->getMDKindID("nontemporal"), Node);
SI->setAlignment(16);
// Remove intrinsic.
CI->eraseFromParent();
return;
} else {
bool PD128 = false, PD256 = false, PS128 = false, PS256 = false;
if (Name == "llvm.x86.avx.vpermil.pd.256")
PD256 = true;
else if (Name == "llvm.x86.avx.vpermil.pd")
PD128 = true;
else if (Name == "llvm.x86.avx.vpermil.ps.256")
PS256 = true;
else if (Name == "llvm.x86.avx.vpermil.ps")
PS128 = true;
if (PD256 || PD128 || PS256 || PS128) {
Value *Op0 = CI->getArgOperand(0);
unsigned Imm = cast<ConstantInt>(CI->getArgOperand(1))->getZExtValue();
SmallVector<Constant*, 8> Idxs;
if (PD128)
for (unsigned i = 0; i != 2; ++i)
Idxs.push_back(Builder.getInt32((Imm >> i) & 0x1));
else if (PD256)
for (unsigned l = 0; l != 4; l+=2)
for (unsigned i = 0; i != 2; ++i)
Idxs.push_back(Builder.getInt32(((Imm >> (l+i)) & 0x1) + l));
else if (PS128)
for (unsigned i = 0; i != 4; ++i)
Idxs.push_back(Builder.getInt32((Imm >> (2 * i)) & 0x3));
else if (PS256)
for (unsigned l = 0; l != 8; l+=4)
for (unsigned i = 0; i != 4; ++i)
Idxs.push_back(Builder.getInt32(((Imm >> (2 * i)) & 0x3) + l));
else
llvm_unreachable("Unexpected function");
Rep = Builder.CreateShuffleVector(Op0, Op0, ConstantVector::get(Idxs));
} else {
llvm_unreachable("Unknown function for CallInst upgrade.");
}
}
CI->replaceAllUsesWith(Rep);
CI->eraseFromParent();
return;
}
switch (NewFn->getIntrinsicID()) {
default:
llvm_unreachable("Unknown function for CallInst upgrade.");
case Intrinsic::ctlz:
case Intrinsic::cttz: {
assert(CI->getNumArgOperands() == 1 &&
"Mismatch between function args and call args");
StringRef Name = CI->getName();
CI->setName(Name + ".old");
CI->replaceAllUsesWith(Builder.CreateCall2(NewFn, CI->getArgOperand(0),
Builder.getFalse(), Name));
CI->eraseFromParent();
return;
}
case Intrinsic::objectsize: {
StringRef Name = CI->getName();
CI->setName(Name + ".old");
CI->replaceAllUsesWith(Builder.CreateCall3(NewFn, CI->getArgOperand(0),
CI->getArgOperand(1),
Builder.getInt32(0), Name));
CI->eraseFromParent();
return;
}
}
}
// This tests each Function to determine if it needs upgrading. When we find
// one we are interested in, we then upgrade all calls to reflect the new
// function.
void llvm::UpgradeCallsToIntrinsic(Function* F) {
assert(F && "Illegal attempt to upgrade a non-existent intrinsic.");
// Upgrade the function and check if it is a totaly new function.
Function *NewFn;
if (UpgradeIntrinsicFunction(F, NewFn)) {
if (NewFn != F) {
// Replace all uses to the old function with the new one if necessary.
for (Value::use_iterator UI = F->use_begin(), UE = F->use_end();
UI != UE; ) {
if (CallInst *CI = dyn_cast<CallInst>(*UI++))
UpgradeIntrinsicCall(CI, NewFn);
}
// Remove old function, no longer used, from the module.
F->eraseFromParent();
}
}
}