Files
llvm-6502/lib/IR/User.cpp
Pete Cooper cff40fc84a Replace all accesses to User::OperandList with getter and setter methods. NFC.
We don't want anyone to access OperandList directly as its going to be removed
and computed instead.  This uses getter's and setter's instead in which we
can later change the underlying implementation of OperandList.

Reviewed by Duncan Exon Smith.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@239620 91177308-0d34-0410-b5e6-96231b3b80d8
2015-06-12 17:48:05 +00:00

121 lines
4.4 KiB
C++

//===-- 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) {
// 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));
// Tag this operand list as being a hung off.
HasHungOffUses = true;
}
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);
}
//===----------------------------------------------------------------------===//
// User operator new Implementations
//===----------------------------------------------------------------------===//
void *User::operator new(size_t s, unsigned Us) {
void *Storage = ::operator new(s + sizeof(Use) * Us);
Use *Start = static_cast<Use*>(Storage);
Use *End = Start + Us;
User *Obj = reinterpret_cast<User*>(End);
Obj->setOperandList(Start);
Obj->HasHungOffUses = false;
Obj->NumOperands = Us;
Use::initTags(Start, End);
return Obj;
}
//===----------------------------------------------------------------------===//
// User operator delete Implementation
//===----------------------------------------------------------------------===//
void User::operator delete(void *Usr) {
User *Start = static_cast<User*>(Usr);
Use *Storage = static_cast<Use*>(Usr) - Start->NumOperands;
// If there were hung-off uses, they will have been freed already and
// NumOperands reset to 0, so here we just free the User itself.
::operator delete(Storage);
}
//===----------------------------------------------------------------------===//
// Operator Class
//===----------------------------------------------------------------------===//
Operator::~Operator() {
llvm_unreachable("should never destroy an Operator");
}
} // End llvm namespace