Spiller unfold optimization bug: do not clobber a reusable stack slot value unless it can be modified.

llvm-svn: 44575

to codegen this:

define float @test_extract_elt(<1 x float> * %P) {
	%p = load <1 x float>* %P
	%R = extractelement <1 x float> %p, i32 0
	ret float %R
}

llvm-svn: 44570

llvm-svn: 44569

llvm-svn: 44565

llvm-svn: 44559

llvm-svn: 44558

llvm-svn: 44557

llvm-svn: 44549

llvm-svn: 44546

llvm-svn: 44545

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).

llvm-svn: 44544

llvm-svn: 44543

llvm-svn: 44541

insert new ExitValue after this operand definition.

This fixes PR1828.

llvm-svn: 44539

Thanks goes to PyPy folks for generating broken stuff :)

llvm-svn: 44538

llvm-svn: 44535

llvm-svn: 44534

windows-based hosts, where files are opened in text mode by default.

llvm-svn: 44533

llvm-svn: 44532

llvm-svn: 44531

llvm-svn: 44528

llvm-svn: 44517

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.

llvm-svn: 44487

llvm-svn: 44482

llvm-svn: 44479

information matching did not exactly match the underlying stream's scoping
information.

llvm-svn: 44470

llvm-svn: 44467

llvm-svn: 44460

llvm-svn: 44458

attributes.  While there, I noticed that not all
attribute methods returned a pointer-to-constant,
so I fixed that.

llvm-svn: 44457

function parameters.

llvm-svn: 44452

llvm-svn: 44446

llvm-svn: 44443

llvm-svn: 44437

in the middle of a split basic block, create a new live interval starting at
the def. This avoid artifically extending the live interval over a number of
cycles where it is dead. e.g.

bb1:
       = vr1204   (use / kill) <= new interval starts and ends here.
...
...
vr1204 =          (new def)   <= start a new interval here.
       = vr1204   (use)

llvm-svn: 44436

llvm-svn: 44434

llvm-svn: 44433

llvm-svn: 44428

llvm-svn: 44427

  unsigned char *llvm_cbe_X;
...
  llvm_cbe_X = 0; *((void**)&llvm_cbe_X) = __builtin_stack_save();

instead of:

  llvm_cbe_X = __builtin_stack_save();

See PR1809 for details.

llvm-svn: 44415