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Diffstat (limited to 'contrib/llvm/lib/IR/User.cpp')
-rw-r--r-- | contrib/llvm/lib/IR/User.cpp | 205 |
1 files changed, 205 insertions, 0 deletions
diff --git a/contrib/llvm/lib/IR/User.cpp b/contrib/llvm/lib/IR/User.cpp new file mode 100644 index 0000000..a75abe6 --- /dev/null +++ b/contrib/llvm/lib/IR/User.cpp @@ -0,0 +1,205 @@ +//===-- User.cpp - Implement the User class -------------------------------===// +// +// The LLVM Compiler Infrastructure +// +// This file is distributed under the University of Illinois Open Source +// License. See LICENSE.TXT for details. +// +//===----------------------------------------------------------------------===// + +#include "llvm/IR/User.h" +#include "llvm/IR/Constant.h" +#include "llvm/IR/GlobalValue.h" +#include "llvm/IR/Operator.h" + +namespace llvm { +class BasicBlock; + +//===----------------------------------------------------------------------===// +// User Class +//===----------------------------------------------------------------------===// + +void User::anchor() {} + +void User::replaceUsesOfWith(Value *From, Value *To) { + if (From == To) return; // Duh what? + + assert((!isa<Constant>(this) || isa<GlobalValue>(this)) && + "Cannot call User::replaceUsesOfWith on a constant!"); + + for (unsigned i = 0, E = getNumOperands(); i != E; ++i) + if (getOperand(i) == From) { // Is This operand is pointing to oldval? + // The side effects of this setOperand call include linking to + // "To", adding "this" to the uses list of To, and + // most importantly, removing "this" from the use list of "From". + setOperand(i, To); // Fix it now... + } +} + +//===----------------------------------------------------------------------===// +// User allocHungoffUses Implementation +//===----------------------------------------------------------------------===// + +void User::allocHungoffUses(unsigned N, bool IsPhi) { + assert(HasHungOffUses && "alloc must have hung off uses"); + + static_assert(AlignOf<Use>::Alignment >= AlignOf<Use::UserRef>::Alignment, + "Alignment is insufficient for 'hung-off-uses' pieces"); + static_assert(AlignOf<Use::UserRef>::Alignment >= + AlignOf<BasicBlock *>::Alignment, + "Alignment is insufficient for 'hung-off-uses' pieces"); + + // Allocate the array of Uses, followed by a pointer (with bottom bit set) to + // the User. + size_t size = N * sizeof(Use) + sizeof(Use::UserRef); + if (IsPhi) + size += N * sizeof(BasicBlock *); + Use *Begin = static_cast<Use*>(::operator new(size)); + Use *End = Begin + N; + (void) new(End) Use::UserRef(const_cast<User*>(this), 1); + setOperandList(Use::initTags(Begin, End)); +} + +void User::growHungoffUses(unsigned NewNumUses, bool IsPhi) { + assert(HasHungOffUses && "realloc must have hung off uses"); + + unsigned OldNumUses = getNumOperands(); + + // We don't support shrinking the number of uses. We wouldn't have enough + // space to copy the old uses in to the new space. + assert(NewNumUses > OldNumUses && "realloc must grow num uses"); + + Use *OldOps = getOperandList(); + allocHungoffUses(NewNumUses, IsPhi); + Use *NewOps = getOperandList(); + + // Now copy from the old operands list to the new one. + std::copy(OldOps, OldOps + OldNumUses, NewOps); + + // If this is a Phi, then we need to copy the BB pointers too. + if (IsPhi) { + auto *OldPtr = + reinterpret_cast<char *>(OldOps + OldNumUses) + sizeof(Use::UserRef); + auto *NewPtr = + reinterpret_cast<char *>(NewOps + NewNumUses) + sizeof(Use::UserRef); + std::copy(OldPtr, OldPtr + (OldNumUses * sizeof(BasicBlock *)), NewPtr); + } + Use::zap(OldOps, OldOps + OldNumUses, true); +} + + +// This is a private struct used by `User` to track the co-allocated descriptor +// section. +struct DescriptorInfo { + intptr_t SizeInBytes; +}; + +ArrayRef<const uint8_t> User::getDescriptor() const { + auto MutableARef = const_cast<User *>(this)->getDescriptor(); + return {MutableARef.begin(), MutableARef.end()}; +} + +MutableArrayRef<uint8_t> User::getDescriptor() { + assert(HasDescriptor && "Don't call otherwise!"); + assert(!HasHungOffUses && "Invariant!"); + + auto *DI = reinterpret_cast<DescriptorInfo *>(getIntrusiveOperands()) - 1; + assert(DI->SizeInBytes != 0 && "Should not have had a descriptor otherwise!"); + + return MutableArrayRef<uint8_t>( + reinterpret_cast<uint8_t *>(DI) - DI->SizeInBytes, DI->SizeInBytes); +} + +//===----------------------------------------------------------------------===// +// User operator new Implementations +//===----------------------------------------------------------------------===// + +void *User::allocateFixedOperandUser(size_t Size, unsigned Us, + unsigned DescBytes) { + assert(Us < (1u << NumUserOperandsBits) && "Too many operands"); + + static_assert(sizeof(DescriptorInfo) % sizeof(void *) == 0, "Required below"); + + unsigned DescBytesToAllocate = + DescBytes == 0 ? 0 : (DescBytes + sizeof(DescriptorInfo)); + assert(DescBytesToAllocate % sizeof(void *) == 0 && + "We need this to satisfy alignment constraints for Uses"); + + uint8_t *Storage = static_cast<uint8_t *>( + ::operator new(Size + sizeof(Use) * Us + DescBytesToAllocate)); + Use *Start = reinterpret_cast<Use *>(Storage + DescBytesToAllocate); + Use *End = Start + Us; + User *Obj = reinterpret_cast<User*>(End); + Obj->NumUserOperands = Us; + Obj->HasHungOffUses = false; + Obj->HasDescriptor = DescBytes != 0; + Use::initTags(Start, End); + + if (DescBytes != 0) { + auto *DescInfo = reinterpret_cast<DescriptorInfo *>(Storage + DescBytes); + DescInfo->SizeInBytes = DescBytes; + } + + return Obj; +} + +void *User::operator new(size_t Size, unsigned Us) { + return allocateFixedOperandUser(Size, Us, 0); +} + +void *User::operator new(size_t Size, unsigned Us, unsigned DescBytes) { + return allocateFixedOperandUser(Size, Us, DescBytes); +} + +void *User::operator new(size_t Size) { + // Allocate space for a single Use* + void *Storage = ::operator new(Size + sizeof(Use *)); + Use **HungOffOperandList = static_cast<Use **>(Storage); + User *Obj = reinterpret_cast<User *>(HungOffOperandList + 1); + Obj->NumUserOperands = 0; + Obj->HasHungOffUses = true; + Obj->HasDescriptor = false; + *HungOffOperandList = nullptr; + return Obj; +} + +//===----------------------------------------------------------------------===// +// User operator delete Implementation +//===----------------------------------------------------------------------===// + +void User::operator delete(void *Usr) { + // Hung off uses use a single Use* before the User, while other subclasses + // use a Use[] allocated prior to the user. + User *Obj = static_cast<User *>(Usr); + if (Obj->HasHungOffUses) { + assert(!Obj->HasDescriptor && "not supported!"); + + Use **HungOffOperandList = static_cast<Use **>(Usr) - 1; + // drop the hung off uses. + Use::zap(*HungOffOperandList, *HungOffOperandList + Obj->NumUserOperands, + /* Delete */ true); + ::operator delete(HungOffOperandList); + } else if (Obj->HasDescriptor) { + Use *UseBegin = static_cast<Use *>(Usr) - Obj->NumUserOperands; + Use::zap(UseBegin, UseBegin + Obj->NumUserOperands, /* Delete */ false); + + auto *DI = reinterpret_cast<DescriptorInfo *>(UseBegin) - 1; + uint8_t *Storage = reinterpret_cast<uint8_t *>(DI) - DI->SizeInBytes; + ::operator delete(Storage); + } else { + Use *Storage = static_cast<Use *>(Usr) - Obj->NumUserOperands; + Use::zap(Storage, Storage + Obj->NumUserOperands, + /* Delete */ false); + ::operator delete(Storage); + } +} + +//===----------------------------------------------------------------------===// +// Operator Class +//===----------------------------------------------------------------------===// + +Operator::~Operator() { + llvm_unreachable("should never destroy an Operator"); +} + +} // End llvm namespace |