I think there are good reasons to change this, but in the interests
of short-term stability, make SmallVector<...,0> reserve non-zero
capacity in its constructors. This means that SmallVector<...,0>
uses more memory than SmallVector<...,1> and should really only be
used (unless/until this workaround is removed) by clients that
care about using SmallVector with an incomplete type.
llvm-svn: 112147
- Cache used characters in a bitset to reduce memory overhead to just 32 bytes.
- On my core2 this code is faster except when the checked string was very short
(smaller than the list of delimiters).
llvm-svn: 111817
We must complete the DFS, otherwise we might miss needed phi-defs, and
prematurely color live ranges with a non-dominating value.
This is not a big deal since we get to color more of the CFG and the next
mapValue call will be faster.
llvm-svn: 111397
implementations of equality comparison and hash computation. This
can be used to optimize node lookup by avoiding creating lots of
temporary ID values just for hashing and comparison purposes.
llvm-svn: 111130
target triple and straightens it out. This does less than gcc's script
config.sub, for example it turns i386-mingw32 into i386--mingw32 not
i386-pc-mingw32, but it does a decent job of turning funky triples into
something that the rest of the Triple class can understand. The plan
is to use this to canonicalize triple's when they are first provided
by users, and have the rest of LLVM only deal with canonical triples.
Once this is done the special case workarounds in the Triple constructor
can be removed, making the class more regular and easier to use. The
comments and unittests for the Triple class are already adjusted in this
patch appropriately for this brave new world of increased uniformity.
llvm-svn: 110909
handles with a pointer to the containing map. When a map is copied, these
pointers need to be corrected to point to the new map. If not, then consider
the case of a map M1 which maps a value V to something. Create a copy M2 of
M1. At this point there are two value handles on V, one representing V as a
key in M1, the other representing V as a key in M2. But both value handles
point to M1 as the containing map. Now delete V. The value handles remove
themselves from their containing map (which destroys them), but only the first
value handle is successful: the second one cannot remove itself from M1 as
(once the first one has removed itself) there is nothing there to remove; it
is therefore not destroyed. This causes an assertion failure "All references
to V were not removed?".
llvm-svn: 109851
with an existing allocator. The interesting use case of this
is that it allows "StringMap<whatever, BumpPtrAllocator&>" for
when you want to allocate out of a preexisting bump pointer
allocator owned by someone else.
llvm-svn: 109213
replaced by a bigger array in SmallPtrSet (by overridding it), instead just use a
pointer to the start of the storage, and have SmallPtrSet pass in the value to use.
This has the disadvantage that SmallPtrSet becomes bigger by one pointer. It has
the advantage that it no longer uses tricky C++ rules, and is clearly correct while
I'm not sure the previous version was. This was inspired by g++-4.6 pointing out
that SmallPtrSetImpl was writing off the end of SmallArray, which it was. Since
SmallArray is replaced with a bigger array in SmallPtrSet, the write was still to
valid memory. But it was writing off the end of the declared array type - sounds
kind of dubious to me, like it sounded dubious to g++-4.6. Maybe g++-4.6 is wrong
and this construct is perfectly valid and correctly compiled by all compilers, but
I think it is better to avoid the whole can of worms by avoiding this construct.
llvm-svn: 107285
SmallArray[SmallSize] in the SmallPtrSetIteratorImpl, and this is
one off the end of the array. For those who care, right now gcc
warns about writing off the end because it is confused about the
declaration of SmallArray as having length 1 in the parent class
SmallPtrSetIteratorImpl. However if you tweak code to unconfuse
it, then it still warns about writing off the end of the array,
because of this buffer overflow. In short, even with this fix
gcc-4.6 will warn about writing off the end of the array, but now
that is only because it is confused.
llvm-svn: 107200
the Profile method. Currently this only works with the default FoldingSetTraits
implementation.
The point of this is to allow nodes to not store context values which are only
used during profiling. A better solution would thread this value through the
folding algorithms, but then those would need to be (1) templated and
(2) non-opaque.
llvm-svn: 105819
