mirror of
https://github.com/RPCSX/llvm.git
synced 2024-12-05 18:37:17 +00:00
b1dbcd886a
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@51143 91177308-0d34-0410-b5e6-96231b3b80d8
163 lines
4.5 KiB
C++
163 lines
4.5 KiB
C++
//===-- Use.cpp - Implement the Use class ---------------------------------===//
|
|
//
|
|
// 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 algorithm for finding the User of a Use.
|
|
//
|
|
//===----------------------------------------------------------------------===//
|
|
|
|
#include "llvm/User.h"
|
|
|
|
namespace llvm {
|
|
|
|
//===----------------------------------------------------------------------===//
|
|
// Use swap Implementation
|
|
//===----------------------------------------------------------------------===//
|
|
|
|
void Use::swap(Use &RHS) {
|
|
Value *V1(Val);
|
|
Value *V2(RHS.Val);
|
|
if (V1 != V2) {
|
|
if (V1) {
|
|
removeFromList();
|
|
}
|
|
|
|
if (V2) {
|
|
RHS.removeFromList();
|
|
Val = V2;
|
|
V2->addUse(*this);
|
|
} else {
|
|
Val = 0;
|
|
}
|
|
|
|
if (V1) {
|
|
RHS.Val = V1;
|
|
V1->addUse(RHS);
|
|
} else {
|
|
RHS.Val = 0;
|
|
}
|
|
}
|
|
}
|
|
|
|
//===----------------------------------------------------------------------===//
|
|
// Use getImpliedUser Implementation
|
|
//===----------------------------------------------------------------------===//
|
|
|
|
const Use *Use::getImpliedUser() const {
|
|
const Use *Current = this;
|
|
|
|
while (true) {
|
|
unsigned Tag = extractTag<PrevPtrTag, fullStopTag>((Current++)->Prev);
|
|
switch (Tag) {
|
|
case zeroDigitTag:
|
|
case oneDigitTag:
|
|
continue;
|
|
|
|
case stopTag: {
|
|
++Current;
|
|
ptrdiff_t Offset = 1;
|
|
while (true) {
|
|
unsigned Tag = extractTag<PrevPtrTag, fullStopTag>(Current->Prev);
|
|
switch (Tag) {
|
|
case zeroDigitTag:
|
|
case oneDigitTag:
|
|
++Current;
|
|
Offset = (Offset << 1) + Tag;
|
|
continue;
|
|
default:
|
|
return Current + Offset;
|
|
}
|
|
}
|
|
}
|
|
|
|
case fullStopTag:
|
|
return Current;
|
|
}
|
|
}
|
|
}
|
|
|
|
//===----------------------------------------------------------------------===//
|
|
// Use initTags Implementation
|
|
//===----------------------------------------------------------------------===//
|
|
|
|
Use *Use::initTags(Use * const Start, Use *Stop, ptrdiff_t Done) {
|
|
ptrdiff_t Count = Done;
|
|
while (Start != Stop) {
|
|
--Stop;
|
|
Stop->Val = 0;
|
|
if (!Count) {
|
|
Stop->Prev = reinterpret_cast<Use**>(Done == 0 ? fullStopTag : stopTag);
|
|
++Done;
|
|
Count = Done;
|
|
} else {
|
|
Stop->Prev = reinterpret_cast<Use**>(Count & 1);
|
|
Count >>= 1;
|
|
++Done;
|
|
}
|
|
}
|
|
|
|
return Start;
|
|
}
|
|
|
|
//===----------------------------------------------------------------------===//
|
|
// Use zap Implementation
|
|
//===----------------------------------------------------------------------===//
|
|
|
|
void Use::zap(Use *Start, const Use *Stop, bool del) {
|
|
if (del) {
|
|
while (Start != Stop) {
|
|
(--Stop)->~Use();
|
|
}
|
|
::operator delete(Start);
|
|
return;
|
|
}
|
|
|
|
while (Start != Stop) {
|
|
(Start++)->set(0);
|
|
}
|
|
}
|
|
|
|
//===----------------------------------------------------------------------===//
|
|
// AugmentedUse layout struct
|
|
//===----------------------------------------------------------------------===//
|
|
|
|
struct AugmentedUse : Use {
|
|
User *ref;
|
|
AugmentedUse(); // not implemented
|
|
};
|
|
|
|
|
|
//===----------------------------------------------------------------------===//
|
|
// Use getUser Implementation
|
|
//===----------------------------------------------------------------------===//
|
|
|
|
User *Use::getUser() const {
|
|
const Use *End = getImpliedUser();
|
|
User *She = static_cast<const AugmentedUse*>(End - 1)->ref;
|
|
She = extractTag<Tag, tagOne>(She)
|
|
? llvm::stripTag<tagOne>(She)
|
|
: reinterpret_cast<User*>(const_cast<Use*>(End));
|
|
|
|
return She;
|
|
}
|
|
|
|
//===----------------------------------------------------------------------===//
|
|
// User allocHungoffUses Implementation
|
|
//===----------------------------------------------------------------------===//
|
|
|
|
Use *User::allocHungoffUses(unsigned N) const {
|
|
Use *Begin = static_cast<Use*>(::operator new(sizeof(Use) * N
|
|
+ sizeof(AugmentedUse)
|
|
- sizeof(Use)));
|
|
Use *End = Begin + N;
|
|
static_cast<AugmentedUse&>(End[-1]).ref = addTag(this, tagOne);
|
|
return Use::initTags(Begin, End);
|
|
}
|
|
|
|
} // End llvm namespace
|