Patch by Matthijs Kooijman!

llvm-svn: 50861

also need to be checked for memory modifying instructions before we
can sink them.  THis fixes the second half of PR2297.

llvm-svn: 50860

delete the first store in:

store x -> p
load p
store y -> p

This is for PR2297.

llvm-svn: 50859

llvm-svn: 50851

llvm-svn: 50836

llvm-svn: 50793

llvm-svn: 50775

We need to update PHIs containing the exiting block, not the exit block.  We really should come up with better names for these.

llvm-svn: 50770

llvm-svn: 50713

llvm-svn: 50699

llvm-svn: 50696

llvm-svn: 50695

ComputeMaskedBits.

llvm-svn: 50692

themselves weren't in the anonymous namespace.

llvm-svn: 50673

DemoteRegToStack doesn't work with MRVs yet, because it relies on the
ability to load/store things.

This fixes PR2285.

llvm-svn: 50667

using dyn_cast<> on already freed memory.

llvm-svn: 50618

llvm-svn: 50604

llvm-svn: 50600

llvm-svn: 50591

llvm-svn: 50586

llvm-svn: 50582

llvm-svn: 50564

from x86-64 calling convention work.

llvm-svn: 50545

fixes the 254.gap regression on x86 and the 403.gcc regression on x86-64.

llvm-svn: 50537

2) Return NULL instead of false in several places for tidiness.
3) fix a bug optimizing  sprintf(p, "%c", x)

llvm-svn: 50521

a FunctionPass.  This makes it simpler, fixes dozens of bugs, adds
a couple of minor features, and shrinks is considerably: from
2214 to 1437 lines.

llvm-svn: 50520

llvm-svn: 50473

to instcombine.

llvm-svn: 50472

llvm-svn: 50464

Revert r50441.  The original code was correct.  Add some more comments so that I don't make the same mistake in the future.

llvm-svn: 50446

we were checking for it in the wrong order.  This caused a miscompilation because the
return slot optimization assumes that the call it is dealing with is NOT a memcpy.

llvm-svn: 50444

llvm-svn: 50442

of this was suggested by Chris.

llvm-svn: 50441

llvm-svn: 50437

llvm-svn: 50436

This fixes the second half of PR2262

llvm-svn: 50430

llvm-svn: 50428

generalizes the previous code to handle the case when the string is not
an immediate to the strlen call (for example, crazy stuff like 
strlen(c ? "foo" : "bart"+1) -> 3).  This implements 
gcc.c-torture/execute/builtins/strlen-2.c.  I will generalize other
cases in simplifylibcalls to use the same routine later.

llvm-svn: 50408

llvm-svn: 50406

llvm-svn: 50390