Turn this:
movswl  %ax, %eax
movl    %eax, -36(%ebp)
xorl    %edi, -36(%ebp)
into
movswl  %ax, %eax
xorl    %edi, %eax
movl    %eax, -36(%ebp)
by unfolding the load / store xorl into an xorl and a store when we know the
value in the spill slot is available in a register. This doesn't change the
number of instructions but reduce the number of times memory is accessed.

Also unfold some load folding instructions and reuse the value when similar
situation presents itself.

llvm-svn: 42947

register used by the unfolded instructions. User can also specify whether to
unfold the load, the store, or both.

llvm-svn: 42946

llvm-svn: 42945

llvm-svn: 42935

for fastcc from X86CallingConv.td.  This means that nested functions
are not supported for calling convention 'fastcc'.

llvm-svn: 42934

that includes the string "st". This probably fixes the regression on
Darwin.

llvm-svn: 42932

Do not filter memmove.

llvm-svn: 42930

Thanks to Török Edvin for helping to track this down.

llvm-svn: 42927

longer be created for fastcc functions.

llvm-svn: 42925

llvm-svn: 42924

llvm-svn: 42922

llvm-svn: 42921

llvm-svn: 42920

llvm-svn: 42919

pointer correctly.

llvm-svn: 42918

llvm-svn: 42916

llvm-svn: 42913

from user input strings.

Such conversions are more intricate and subtle than they may appear;
it is unlikely I have got it completely right first time.  I would
appreciate being informed of any bugs and incorrect roundings you
might discover.

llvm-svn: 42912

llvm-svn: 42911

If we're trying to be arbitrary precision, unsigned char clearly won't cut it.  Needed for dec->bin conversions.

llvm-svn: 42910

llvm-svn: 42909

function symbol name instead of a codegen-assigned function
number.

Thanks Evan! :-)

llvm-svn: 42908

llvm-svn: 42907

is a scalar integer.

llvm-svn: 42906

llvm-svn: 42905

llvm-svn: 42904

llvm-svn: 42903

llvm-svn: 42901

llvm-svn: 42900

(almost) a register copy. However, it always coalesced to the register of the
RHS (the super-register). All uses of the result of a EXTRACT_SUBREG are sub-
register uses which adds subtle complications to load folding, spiller rewrite,
etc.

llvm-svn: 42899

llvm-svn: 42898

llvm-svn: 42897

llvm-svn: 42896

llvm-svn: 42895

llvm-svn: 42894

llvm-svn: 42893

llvm-svn: 42892

Fix DecomposeSimpleLinearExpr to handle simple constants better.
Don't nuke gep(bitcast(allocation)) if the bitcast(allocation) will
fold the allocation.  This fixes PR1728 and Instcombine/malloc3.ll

llvm-svn: 42891

llvm-svn: 42890

the extra bits are all zeros.  This allows  "010" and "010000" to be
treated as equal.

llvm-svn: 42889