llvm-svn: 43781

When the allocator rewrite a spill register with new virtual register, it replaces other operands of the same register. Watch out for situations where
only some of the operands are sub-register uses.

llvm-svn: 43776

llvm-svn: 43764

llvm-svn: 43763

other uses. There was a overly restricted check that prevented some obvious
cases.

llvm-svn: 43762

llvm-svn: 43755

llvm-svn: 43754

llvm-svn: 43751

llvm-svn: 43744

Thanks for the suggestions Bill :-)

llvm-svn: 43742

parameters.  Rename ValueRefList to ParamList
in AsmParser, since its only use is for parameters.

llvm-svn: 43734

size for the field we get ABI padding automatically, so
no need to put it in again when we emit the field.

llvm-svn: 43720

register coalescer interface: RegisterCoalescing.

llvm-svn: 43714

llvm-svn: 43700

defined on the same instruction. This fixes PR1767.

llvm-svn: 43699

llvm-svn: 43692

should only effect x86 when using long double.  Now
12/16 bytes are output for long double globals (the
exact amount depends on the alignment).  This brings
globals in line with the rest of LLVM: the space
reserved for an object is now always the ABI size.
One tricky point is that only 10 bytes should be
output for long double if it is a field in a packed
struct, which is the reason for the additional
argument to EmitGlobalConstant.

llvm-svn: 43688

llvm-svn: 43684

If an interval is being undone clear its preference as well since the source interval may have been undone as well.

llvm-svn: 43670

can be eliminated by the allocator is the destination and source targets the
same register. The most common case is when the source and destination registers
are in different class. For example, on x86 mov32to32_ targets GR32_ which
contains a subset of the registers in GR32.

The allocator can do 2 things:
1. Set the preferred allocation for the destination of a copy to that of its source.
2. After allocation is done, change the allocation of a copy destination (if
   legal) so the copy can be eliminated.

This eliminates 443 extra moves from 403.gcc.

llvm-svn: 43662

llvm-svn: 43652

llvm-svn: 43651

llvm-svn: 43644

llvm-svn: 43639

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.

llvm-svn: 43620

- Some code clean up.

llvm-svn: 43606

llvm-svn: 43551

llvm-svn: 43550

llvm-svn: 43542

llvm-svn: 43541

llvm-svn: 43535

llvm-svn: 43511

storing an i170 on a 32 bit machine.  This is first
promoted to a trunc-i170 store of an i256.  On a
little-endian machine this expands to a store of
an i128 and a trunc-i42 store of an i128.  The
trunc-i42 store is further expanded to a trunc-i42
store of an i64, then to a store of an i32 and a
trunc-i10 store of an i32.  At this point the operand
type is legal (i32) and expansion stops (legalization
of the trunc-i10 needs to be handled in LegalizeDAG.cpp).
On big-endian machines the high bits are stored first,
and some bit-fiddling is needed in order to generate
aligned stores.

llvm-svn: 43499

offload to getStore rather than trying to handle
both cases at once (the assertions for example
assume the store really is truncating).

llvm-svn: 43498

llvm-svn: 43470

transformation. Previously, it's restricted by ensuring the number of load uses
is one. Now the restriction is loosened up by allowing setcc uses to be
"extended" (e.g. setcc x, c, eq -> setcc sext(x), sext(c), eq).

llvm-svn: 43465

llvm-svn: 43464

of offset and the alignment of ptr if these are both powers of
2.  While the ptr alignment is guaranteed to be a power of 2,
there is no reason to think that offset is.  For example, if
offset is 12 (the size of a long double on x86-32 linux) and
the alignment of ptr is 8, then the alignment of ptr+offset
will in general be 4, not 8.  Introduce a function MinAlign,
lifted from gcc, for computing the minimum guaranteed alignment.
I've tried to fix up everywhere under lib/CodeGen/SelectionDAG/.
I also changed some places that weren't wrong (because both values
were a power of 2), as a defensive change against people copying
and pasting the code.
Hopefully someone who cares about alignment will review the rest
of LLVM and fix up the remaining places.  Since I'm on x86 I'm
not very motivated to do this myself...

llvm-svn: 43421

  FE.
- Explicitly pass in the alignment of the load & store.
- XFAIL 2007-10-23-UnalignedMemcpy.ll because llc has a bug that crashes on
  unaligned pointers.

llvm-svn: 43398

llvm-svn: 43359