manually performing the comparison. This allows the special
case to work correctly even in the case where someone is
experimenting with a different comparison function :-).
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@49670 91177308-0d34-0410-b5e6-96231b3b80d8
Specifically, introduction of XXX::Create methods
for Users that have a potentially variable number of
Uses.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@49277 91177308-0d34-0410-b5e6-96231b3b80d8
Parse reversed smax and umax as smin and umin and express them with negative
or binary-not SCEVs (which are really just subtract under the hood).
Parse 'xor %x, -1' as (-1 - %x).
Remove dead code (ConstantInt::get always returns a ConstantInt).
Don't use getIntegerSCEV(-1, Ty). The first value is an int, then it gets
passed into a uint64_t. Instead, create the -1 directly from
ConstantInt::getAllOnesValue().
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@47360 91177308-0d34-0410-b5e6-96231b3b80d8
Also, noalias arguments are be considered "like" stack allocated ones for this purpose, because
the only way they can be modref'ed is if they escape somewhere in the current function.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@47247 91177308-0d34-0410-b5e6-96231b3b80d8
variable (with step 1) and m is its final value. Then, the correct trip
count is SMAX(m,n)-n. Previously, we used SMAX(0,m-n), but m-n may
overflow and can't in general be interpreted as signed.
Patch by Nick Lewycky.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@47007 91177308-0d34-0410-b5e6-96231b3b80d8
to the RHS. This simple change allows to compute loop iteration count
for loops with condition similar to the one in the testcase (which seems
to be quite common).
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@46959 91177308-0d34-0410-b5e6-96231b3b80d8
arbitrary iteration.
The patch:
1) changes SCEVSDivExpr into SCEVUDivExpr,
2) replaces PartialFact() function with BinomialCoefficient(); the
computations (essentially, the division) in BinomialCoefficient() are
performed with the apprioprate bitwidth necessary to avoid overflow;
unsigned division is used instead of the signed one.
Computations in BinomialCoefficient() require support from the code
generator for APInts. Currently, we use a hack rounding up the
neccessary bitwidth to the nearest power of 2. The hack is easy to turn
off in future.
One remaining issue: we assume the divisor of the binomial coefficient
formula can be computed accurately using 16 bits. It means we can handle
AddRecs of length up to 9. In future, we should use APInts to evaluate
the divisor.
Thanks to Nicholas for cooperation!
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@46955 91177308-0d34-0410-b5e6-96231b3b80d8
can't be aliased to other known objects. This allows us to know that byval
pointer args don't alias globals, etc.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@46315 91177308-0d34-0410-b5e6-96231b3b80d8
and readnone for functions with bodies because it
broke llvm-gcc-4.2 bootstrap. It turns out that,
because of LLVM's array_ref hack, gcc was computing
pure/const attributes wrong (now fixed by turning
off the gcc ipa-pure-const pass).
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@44937 91177308-0d34-0410-b5e6-96231b3b80d8
Changes from me implementing different way of representing points-to anything.
Changes from me that improve slightly on LCD.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@44895 91177308-0d34-0410-b5e6-96231b3b80d8
Reimplement the xform in Analysis/ConstantFolding.cpp where we can use
targetdata to validate that it is safe. While I'm in there, fix some const
correctness issues and generalize the interface to the "operand folder".
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@44817 91177308-0d34-0410-b5e6-96231b3b80d8
not yet clear why, but in the meantime work around the
problem by making less use of readnone/readonly info.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@44626 91177308-0d34-0410-b5e6-96231b3b80d8
throw exceptions", just mark intrinsics with the nounwind
attribute. Likewise, mark intrinsics as readnone/readonly
and get rid of special aliasing logic (which didn't use
anything more than this anyway).
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@44544 91177308-0d34-0410-b5e6-96231b3b80d8
into alias analysis. This meant updating the API
which now has versions of the getModRefBehavior,
doesNotAccessMemory and onlyReadsMemory methods
which take a callsite parameter. These should be
used unless the callsite is not known, since in
general they can do a better job than the versions
that take a function. Also, users should no longer
call the version of getModRefBehavior that takes
both a function and a callsite. To reduce the
chance of misuse it is now protected.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@44487 91177308-0d34-0410-b5e6-96231b3b80d8
the function type, instead they belong to functions
and function calls. This is an updated and slightly
corrected version of Reid Spencer's original patch.
The only known problem is that auto-upgrading of
bitcode files doesn't seem to work properly (see
test/Bitcode/AutoUpgradeIntrinsics.ll). Hopefully
a bitcode guru (who might that be? :) ) will fix it.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@44359 91177308-0d34-0410-b5e6-96231b3b80d8
OnlyReadsMemoryFns tables are dead! We
get more, and more accurate, information
from gcc via the readnone and readonly
function attributes.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@44288 91177308-0d34-0410-b5e6-96231b3b80d8
is disabled in the sense that it will refuse to create one from a UDiv
instruction, until the code is better tested.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@44163 91177308-0d34-0410-b5e6-96231b3b80d8
The meaning of getTypeSize was not clear - clarifying it is important
now that we have x86 long double and arbitrary precision integers.
The issue with long double is that it requires 80 bits, and this is
not a multiple of its alignment. This gives a primitive type for
which getTypeSize differed from getABITypeSize. For arbitrary precision
integers it is even worse: there is the minimum number of bits needed to
hold the type (eg: 36 for an i36), the maximum number of bits that will
be overwriten when storing the type (40 bits for i36) and the ABI size
(i.e. the storage size rounded up to a multiple of the alignment; 64 bits
for i36).
This patch removes getTypeSize (not really - it is still there but
deprecated to allow for a gradual transition). Instead there is:
(1) getTypeSizeInBits - a number of bits that suffices to hold all
values of the type. For a primitive type, this is the minimum number
of bits. For an i36 this is 36 bits. For x86 long double it is 80.
This corresponds to gcc's TYPE_PRECISION.
(2) getTypeStoreSizeInBits - the maximum number of bits that is
written when storing the type (or read when reading it). For an
i36 this is 40 bits, for an x86 long double it is 80 bits. This
is the size alias analysis is interested in (getTypeStoreSize
returns the number of bytes). There doesn't seem to be anything
corresponding to this in gcc.
(3) getABITypeSizeInBits - this is getTypeStoreSizeInBits rounded
up to a multiple of the alignment. For an i36 this is 64, for an
x86 long double this is 96 or 128 depending on the OS. This is the
spacing between consecutive elements when you form an array out of
this type (getABITypeSize returns the number of bytes). This is
TYPE_SIZE in gcc.
Since successive elements in a SequentialType (arrays, pointers
and vectors) need to be aligned, the spacing between them will be
given by getABITypeSize. This means that the size of an array
is the length times the getABITypeSize. It also means that GEP
computations need to use getABITypeSize when computing offsets.
Furthermore, if an alloca allocates several elements at once then
these too need to be aligned, so the size of the alloca has to be
the number of elements multiplied by getABITypeSize. Logically
speaking this doesn't have to be the case when allocating just
one element, but it is simpler to also use getABITypeSize in this
case. So alloca's and mallocs should use getABITypeSize. Finally,
since gcc's only notion of size is that given by getABITypeSize, if
you want to output assembler etc the same as gcc then getABITypeSize
is the size you want.
Since a store will overwrite no more than getTypeStoreSize bytes,
and a read will read no more than that many bytes, this is the
notion of size appropriate for alias analysis calculations.
In this patch I have corrected all type size uses except some of
those in ScalarReplAggregates, lib/Codegen, lib/Target (the hard
cases). I will get around to auditing these too at some point,
but I could do with some help.
Finally, I made one change which I think wise but others might
consider pointless and suboptimal: in an unpacked struct the
amount of space allocated for a field is now given by the ABI
size rather than getTypeStoreSize. I did this because every
other place that reserves memory for a type (eg: alloca) now
uses getABITypeSize, and I didn't want to make an exception
for unpacked structs, i.e. I did it to make things more uniform.
This only effects structs containing long doubles and arbitrary
precision integers. If someone wants to pack these types more
tightly they can always use a packed struct.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@43620 91177308-0d34-0410-b5e6-96231b3b80d8
and time usage.
Fixup operator == to make this work, and add a resize method to DenseMap
so we can resize our hashtable once we know how big it should be.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@42269 91177308-0d34-0410-b5e6-96231b3b80d8
into a separate header file.
Next step: merging PostDominatorCalculation.h with DominatorCalculation.h.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@42251 91177308-0d34-0410-b5e6-96231b3b80d8
Use APFloat in UpgradeParser and AsmParser.
Change all references to ConstantFP to use the
APFloat interface rather than double. Remove
the ConstantFP double interfaces.
Use APFloat functions for constant folding arithmetic
and comparisons.
(There are still way too many places APFloat is
just a wrapper around host float/double, but we're
getting there.)
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@41747 91177308-0d34-0410-b5e6-96231b3b80d8
ConstantFoldInstruction on calls) by avoiding Value::getName(). getName() constructs
and returns an std::string, which does heap allocation stuff. This slightly speeds up
instcombine.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@40924 91177308-0d34-0410-b5e6-96231b3b80d8
natural loop canonicalization (which does many cfg xforms) by 4.3x, for
example. This also fixes a bug in postdom dfnumber computation.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@40920 91177308-0d34-0410-b5e6-96231b3b80d8
which dynamically allocates the string result. This speeds up dse on the
testcase from PR1432 from 0.3781s to 0.1804s (2.1x).
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@40838 91177308-0d34-0410-b5e6-96231b3b80d8
speeds up idom by about 45% and postidom by about 33%.
Some extra precautions must be taken not to invalidate densemap iterators.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@40827 91177308-0d34-0410-b5e6-96231b3b80d8
DenseMap instead of an std::map. This speeds up postdomtree
by about 25% and domtree by about 23%. It also speeds up clients,
for example, domfrontier by 11%, mem2reg by 4% and ADCE by 6%.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@40826 91177308-0d34-0410-b5e6-96231b3b80d8
