From c7133f4f3d28c46eeec13b415970a6ba3bdea6b9 Mon Sep 17 00:00:00 2001 From: Andy Ragusa Date: Thu, 18 Jan 2024 15:45:30 -0800 Subject: [PATCH] blah --- libclambcc/Common/ClamBCRegAlloc.cpp | 268 --------------------------- 1 file changed, 268 deletions(-) delete mode 100644 libclambcc/Common/ClamBCRegAlloc.cpp diff --git a/libclambcc/Common/ClamBCRegAlloc.cpp b/libclambcc/Common/ClamBCRegAlloc.cpp deleted file mode 100644 index 7bd83c011b..0000000000 --- a/libclambcc/Common/ClamBCRegAlloc.cpp +++ /dev/null @@ -1,268 +0,0 @@ -/* - * Compile LLVM bytecode to ClamAV bytecode. - * - * Copyright (C) 2009-2010 Sourcefire, Inc. - * - * Authors: Török Edvin - * - * This program is free software; you can redistribute it and/or modify - * it under the terms of the GNU General Public License version 2 as - * published by the Free Software Foundation. - * - * This program is distributed in the hope that it will be useful, - * but WITHOUT ANY WARRANTY; without even the implied warranty of - * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the - * GNU General Public License for more details. - * - * You should have received a copy of the GNU General Public License - * along with this program; if not, write to the Free Software - * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, - * MA 02110-1301, USA. - */ -#include "ClamBCModule.h" -#include "ClamBCUtilities.h" -#include "clambc.h" - -#include -//#include "llvm/Analysis/LiveValues.h" -//#include "llvm/Config/config.h" -#include -#include -#include -#include -#include -#include -#include -#include - -using namespace llvm; -// We do have a virtually unlimited number of registers, but it is more cache -// efficient at runtime if we use a small number of them. -// Also it is easier for the interpreter if there are no phi nodes, -// so we transform phi nodes into a store/load pair into a temporary stack -// location. -// We don't use LLVM's register allocators, because they are for -// targets with fixed number of registers, and a much simpler allocator -// suffices for us. - -/*TODO: Should rework this so that we are not changing things with open iterators.*/ -void ClamBCRegAlloc::handlePHI(PHINode *PN) -{ - BasicBlock *BB = PN->getIncomingBlock(0); - for (unsigned i = 1; i < PN->getNumIncomingValues(); i++) { - BB = DT->findNearestCommonDominator(BB, PN->getIncomingBlock(i)); - } - Function *pFunc = BB->getParent(); - BasicBlock *pEntry = llvm::cast(pFunc->begin()); - Instruction *pFirst = llvm::cast(pEntry->begin()); - AllocaInst *AI = new AllocaInst(PN->getType(), pFunc->getAddressSpace(), ".phi", - pFirst); - llvm::IRBuilder<> builder(PN->getContext()); - unsigned MDDbgKind = PN->getContext().getMDKindID("dbg"); - if (MDDbgKind) { - if (MDNode *Dbg = PN->getMetadata(MDDbgKind)) { - DebugLoc dl(Dbg); - builder.SetCurrentDebugLocation(dl); - } - } - for (unsigned i = 0; i < PN->getNumIncomingValues(); i++) { - BasicBlock *BB = PN->getIncomingBlock(i); - Value *V = PN->getIncomingValue(i); - builder.SetInsertPoint(BB->getTerminator()); - Instruction *I = builder.CreateStore(V, AI); - builder.SetInstDebugLocation(I); - } - BasicBlock::iterator It(PN); - do { - ++It; - } while (isa(It)); - builder.SetInsertPoint(&*It); - LoadInst *LI = builder.CreateLoad(AI, ".phiload"); - builder.SetInstDebugLocation(LI); - PN->replaceAllUsesWith(LI); - PN->eraseFromParent(); -} - -bool ClamBCRegAlloc::runOnFunction(Function &F) -{ - ValueMap.clear(); - RevValueMap.clear(); - DT = &getAnalysis().getDomTree(); - bool Changed = false; - for (Function::iterator I = F.begin(), E = F.end(); I != E; ++I) { - BasicBlock &BB = *I; - BasicBlock::iterator J = BB.begin(); - while (J != BB.end()) { - PHINode *PN = dyn_cast(J); - if (!PN) - break; - ++J; - handlePHI(PN); - } - } - - unsigned id = 0; - for (Function::arg_iterator I = F.arg_begin(), E = F.arg_end(); - I != E; ++I) { - Argument *A = llvm::cast(I); - ValueMap[A] = id; - if (RevValueMap.size() == id) { - RevValueMap.push_back(A); - } else { - errs() << id << " " << __FILE__ << ":" << __LINE__ << "\n"; - } - ++id; - } - - for (inst_iterator I = inst_begin(F), E = inst_end(F); I != E; ++I) { - Instruction *II = llvm::cast(&*I); - if (ValueMap.count(II)) - continue; - if (II->getType()->getTypeID() == Type::VoidTyID) { - ValueMap[II] = ~0u; - continue; - } - if (II->use_empty() && !II->mayHaveSideEffects()) { - SkipMap.insert(II); - ValueMap[II] = ~0u; - continue; - } - if (CastInst *BC = dyn_cast(II)) { - if (BitCastInst *BCI = dyn_cast(BC)) { - if (!BCI->isLosslessCast()) { - ClamBCStop("Non lossless bitcast is not supported", BCI); - } - const Type *SrcTy = BC->getOperand(0)->getType(); - const Type *DstTy = BC->getType(); - const PointerType *SPTy, *DPTy; - while ((SPTy = dyn_cast(SrcTy))) { - DPTy = dyn_cast(DstTy); - if (!DPTy) { - ClamBCStop("Cast from pointer to non-pointer element", - BCI); - } - SrcTy = SPTy->getElementType(); - DstTy = DPTy->getElementType(); - } - - if (AllocaInst *AI = dyn_cast(BCI->getOperand(0))) { - if (!AI->isArrayAllocation()) { - // we need to use a GEP 0,0 for bitcast here - ValueMap[II] = id; - if (RevValueMap.size() == id) { - RevValueMap.push_back(II); - } else { - errs() << id << " " << __FILE__ << ":" << __LINE__ << "\n"; - } - ++id; - continue; - } - } - SkipMap.insert(II); - ValueMap[II] = getValueID(II->getOperand(0)); - continue; - } - } - if (II->hasOneUse()) { - // single-use store to alloca -> store directly to alloca - if (StoreInst *SI = dyn_cast(*II->use_begin())) { - if (AllocaInst *AI = dyn_cast(SI->getPointerOperand())) { - if (!ValueMap.count(AI)) { - ValueMap[AI] = id; - if (RevValueMap.size() == id) { - RevValueMap.push_back(II); - } else { - errs() << id << " " << __FILE__ << ":" << __LINE__ << "\n"; - } - ++id; - } - ValueMap[II] = getValueID(AI); - continue; - } - } - // single-use of load from alloca -> use directly value id of alloca - //TODO: we must check for intervening stores here, better use memdep! - /* if (LoadInst *LI = dyn_cast(II)) { - if (AllocaInst *AI = dyn_cast(LI->getPointerOperand())) { - ValueMap[LI] = getValueID(AI); - SkipMap.insert(LI); - continue; - } - }*/ - } - ValueMap[II] = id; - if (RevValueMap.size() == id) { - RevValueMap.push_back(II); - } else { - errs() << id << " " << __FILE__ << ":" << __LINE__ << "\n"; - } - ++id; - } - //TODO: reduce the number of virtual registers used, by using - // an algorithms that walks the dominatortree and does value liveness - // analysis. - return Changed; -} - -void ClamBCRegAlloc::dump() const -{ - for (ValueIDMap::const_iterator I = ValueMap.begin(), E = ValueMap.end(); - I != E; ++I) { - errs() << *I->first << " = " << I->second << "\n"; - } -} - -void ClamBCRegAlloc::revdump() const -{ - for (unsigned i = 0; i < RevValueMap.size(); ++i) { - errs() << i << ": "; - RevValueMap[i]->print(errs(), 0); - errs() << "\n"; - } -} - -unsigned ClamBCRegAlloc::buildReverseMap(std::vector &reverseMap) -{ - // Check using the older building code to determine changes due to building difference - // Note: this code can be removed if necessary - unsigned max = 0; - for (ValueIDMap::iterator I = ValueMap.begin(), E = ValueMap.end(); I != E; ++I) { - if (const Instruction *II = dyn_cast(I->first)) { - if (SkipMap.count(II)) - continue; - } - if (I->second == ~0u) - continue; - if (I->second > max) - max = I->second; - } - if ((max != 0) && (max + 1 != RevValueMap.size())) { - errs() << "mismatch in expected number of values in map at "; - errs() << __FILE__ << ":" << __LINE__ << "\n"; - errs() << "found " << max + 1 << ", expected " << RevValueMap.size() << "\n"; - revdump(); - assert(max + 1 == RevValueMap.size()); - return 0; - } - - // New building code, copies previously-built vector - reverseMap.resize(RevValueMap.size()); - for (unsigned i = 0; i < RevValueMap.size(); ++i) { - reverseMap[i] = RevValueMap[i]; - } - return RevValueMap.size(); -} - -void ClamBCRegAlloc::getAnalysisUsage(AnalysisUsage &AU) const -{ - AU.addRequired(); - - // Preserve the CFG, we only eliminate PHIs, and introduce some - // loads/stores. - AU.setPreservesCFG(); -} -char ClamBCRegAlloc::ID = 0; -static RegisterPass X("clambc-ra", - "ClamAV bytecode register allocator"); - -const PassInfo *const ClamBCRegAllocID = &X;