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
Add a new DenseMapInfo::isEqual method to allow clients to redefine
the equality predicate used when probing the hash table.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@42042 91177308-0d34-0410-b5e6-96231b3b80d8
(I've tried to get the info right for all targets,
but I'm not expert on all of them - check yours.)
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@40792 91177308-0d34-0410-b5e6-96231b3b80d8
Due to darwin gcc bug, one version of darwin linker coalesces
static const int, which defauts PassID based pass identification.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@36652 91177308-0d34-0410-b5e6-96231b3b80d8
rules alignment is to pick the alignment that corresponds to the smallest
specified alignment that is larger than the bit width of the type or the
largest specified integer alignment if none are larger than the bitwidth
of the type. For the byte size, the size returned is the next larger
multiple of the alignment for that type (using the above rule). This patch
also changes bit widths from "short" to "uint32_t" to ensure there are
enough bits to specify any bit width that LLVM can handle (currently 2^23);
16-bits isn't enough.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@34431 91177308-0d34-0410-b5e6-96231b3b80d8
after the StructLayout object in memory. This marginally improves locality,
speeding up -load-vn -gcse by ~0.8%.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@34158 91177308-0d34-0410-b5e6-96231b3b80d8
must in order for backends that do want to support large integer types to be
able to function. Consequently, don't assert if the bitwidth > 64 bits
when computing the size and alignment. Instead, compute the size by rounding
up to the next even number of bytes for the size. Compute the alignment
as the same as the LongABIAlignment. These provide reasonable defaults
that the target can override.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@33943 91177308-0d34-0410-b5e6-96231b3b80d8
The Module::setEndianness and Module::setPointerSize methods have been
removed. Instead you can get/set the DataLayout. Adjust thise accordingly.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@33530 91177308-0d34-0410-b5e6-96231b3b80d8
Implement the arbitrary bit-width integer feature. The feature allows
integers of any bitwidth (up to 64) to be defined instead of just 1, 8,
16, 32, and 64 bit integers.
This change does several things:
1. Introduces a new Derived Type, IntegerType, to represent the number of
bits in an integer. The Type classes SubclassData field is used to
store the number of bits. This allows 2^23 bits in an integer type.
2. Removes the five integer Type::TypeID values for the 1, 8, 16, 32 and
64-bit integers. These are replaced with just IntegerType which is not
a primitive any more.
3. Adjust the rest of LLVM to account for this change.
Note that while this incremental change lays the foundation for arbitrary
bit-width integers, LLVM has not yet been converted to actually deal with
them in any significant way. Most optimization passes, for example, will
still only deal with the byte-width integer types. Future increments
will rectify this situation.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@33113 91177308-0d34-0410-b5e6-96231b3b80d8
Three changes:
1. Convert signed integer types to signless versions.
2. Implement the @sext and @zext parameter attributes. Previously the
type of an function parameter was used to determine whether it should
be sign extended or zero extended before the call. This information is
now communicated via the function type's parameter attributes.
3. The interface to LowerCallTo had to be changed in order to accommodate
the parameter attribute information. Although it would have been
convenient to pass in the FunctionType itself, there isn't always one
present in the caller. Consequently, a signedness indication for the
result type and for each parameter was provided for in the interface
to this method. All implementations were changed to make the adjustment
necessary.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@32788 91177308-0d34-0410-b5e6-96231b3b80d8
This patch implements the first increment for the Signless Types feature.
All changes pertain to removing the ConstantSInt and ConstantUInt classes
in favor of just using ConstantInt.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@31063 91177308-0d34-0410-b5e6-96231b3b80d8
