6502/llvm-6502
1
0
Fork 0
mirror of https://github.com/c64scene-ar/llvm-6502.git synced 2024-11-01 15:11:24 +00:00
Code Issues Projects Releases Wiki Activity

UseListOrder: Use std::vector

Browse Source 
I initially used a `SmallVector<>` for `UseListOrder::Shuffle`, which
was a silly choice.  When I realized my error I quickly rolled a custom
data structure.

This commit simplifies it to a `std::vector<>`.  Now that I've had a
chance to measure performance, this data structure isn't part of a
bottleneck, so the additional complexity is unnecessary.

This is part of PR5680.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@214979 91177308-0d34-0410-b5e6-96231b3b80d8
This commit is contained in:
Duncan P. N. Exon Smith 2014-08-06 17:36:08 +00:00
parent af4e76402f
commit 2669f9b34e
1 changed files with 1 additions and 57 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

58
include/llvm/IR/UseListOrder.h
View File

@ -25,67 +25,11 @@ class Module;
class Function;
class Value;
/// \brief Structure to hold a use-list shuffle vector.
///
/// Stores most use-lists locally, but large use-lists use an extra heap entry.
/// Costs two fewer pointers than the equivalent \a SmallVector.
class UseListShuffleVector {
unsigned Size;
union {
unsigned *Ptr;
unsigned Array[6];
} Storage;
bool isSmall() const { return Size <= 6; }
unsigned *data() { return isSmall() ? Storage.Array : Storage.Ptr; }
const unsigned *data() const {
return isSmall() ? Storage.Array : Storage.Ptr;
}
void destroy() {
if (!isSmall())
delete[] Storage.Ptr;
}
void moveUnchecked(UseListShuffleVector &X) {
std::memcpy(this, &X, sizeof(UseListShuffleVector));
X.Size = 0;
}
UseListShuffleVector(const UseListShuffleVector &X) LLVM_DELETED_FUNCTION;
UseListShuffleVector &
operator=(const UseListShuffleVector &X) LLVM_DELETED_FUNCTION;
public:
UseListShuffleVector() : Size(0) {}
UseListShuffleVector(UseListShuffleVector &&X) { moveUnchecked(X); }
UseListShuffleVector &operator=(UseListShuffleVector &&X) {
destroy();
moveUnchecked(X);
return *this;
}
explicit UseListShuffleVector(size_t Size) : Size(Size) {
if (!isSmall())
Storage.Ptr = new unsigned[Size];
}
~UseListShuffleVector() { destroy(); }
typedef unsigned *iterator;
typedef const unsigned *const_iterator;
size_t size() const { return Size; }
iterator begin() { return data(); }
iterator end() { return begin() + size(); }
const_iterator begin() const { return data(); }
const_iterator end() const { return begin() + size(); }
unsigned &operator[](size_t I) { return data()[I]; }
unsigned operator[](size_t I) const { return data()[I]; }
};
/// \brief Structure to hold a use-list order.
struct UseListOrder {
const Value *V;
const Function *F;
UseListShuffleVector Shuffle;
std::vector<unsigned> Shuffle;
UseListOrder(const Value *V, const Function *F, size_t ShuffleSize)
: V(V), F(F), Shuffle(ShuffleSize) {}