return it as a clobber.  This allows GVN to do smart things.

Enhance GVN to be smart about the case when a small load is clobbered
by a larger overlapping load.  In this case, forward the value.  This
allows us to compile stuff like this:

int test(void *P) {
  int tmp = *(unsigned int*)P;
  return tmp+*((unsigned char*)P+1);
}

into:

_test:                                  ## @test
	movl	(%rdi), %ecx
	movzbl	%ch, %eax
	addl	%ecx, %eax
	ret

which has one load.  We already handled the case where the smaller
load was from a must-aliased base pointer.

llvm-svn: 130180

llvm-svn: 130068

llvm-svn: 129932

necessary since gcov counts transitions between blocks. It can't see if you've
run every line in a straight-line function, so we add an edge for it to notice.

llvm-svn: 129905

comment for 80 columns.

llvm-svn: 129904

instrument the program to emit .gcda.
TODO: we should emit slightly different .gcda files when .gcno emission is off.

llvm-svn: 129903

generated by llvm-gcc, since llvm-gcc uses 2 i64s for passing a 4 x float
vector on ARM rather than an i64 array like Clang.

llvm-svn: 129878

delete it.

llvm-svn: 129877

more cases.

llvm-svn: 129876

llvm-svn: 129759

silences Clang's -Wunused-function when building in release mode.

llvm-svn: 129709

llvm-svn: 129644

found by code inspection.

llvm-svn: 129641

llvm-svn: 129632

Break the arc-profile code out to a function like the notes emission code is,
and reorder the functions in the file.

The only functionality change is that we no longer modify the Module when the
Module has no debug info to use.

llvm-svn: 129631

does. Also mostly implement it. Still a work-in-progress, but generates legal
output on crafted test cases.

llvm-svn: 129630

Luis Felipe Strano Moraes!

llvm-svn: 129558

canonical, and generally leads to better code.  Found while looking at
an article about saturating arithmetic.

llvm-svn: 129545

Fix an infinite alternation in JumpThreading where two transforms would repeatedly undo each other.  The solution is to perform more aggressive constant folding to make one of the edges just folded away rather than trying to thread it.
Fixes <rdar://problem/9284786>.

Discovered with CSmith.

llvm-svn: 129538

llvm-svn: 129532

llvm-svn: 129509

instruction around, reducing work.

Greatly simplify handling of debug instructions.  There is no need to
build up a vector of them and then move them into the one predecessor
if we're processing a block.  Instead just rescan the block and *copy*
them into the pred.  If a block gets merged into multiple preds, this
will retain more debug info.

llvm-svn: 129502

llvm-svn: 129501

the same allocation size but different primitive sizes(e.g., <3xi32> and
<4xi32>).  When ScalarRepl promotes them, it can't use a bit cast but
should use a shuffle vector instead.

llvm-svn: 129472

llvm-svn: 129450

Passing unroll parameters (unroll-count, threshold, and partial unroll) via LoopUnroll class's ctor. Doing so 
will allow multiple context with different loop unroll parameters to run.  This is a minor change and no effect 
on existing application.

llvm-svn: 129449

llvm-svn: 129447

llvm-svn: 129419

llvm-svn: 129403

Now that we have a first-class way to represent unaligned loads, the unaligned
load intrinsics are superfluous.

First part of <rdar://problem/8460511>.

llvm-svn: 129401

llvm-svn: 129343

Use debug info in the IR to find the directory/file:line:col. Each time that location changes, bump a counter.

Unlike the existing profiling system, we don't try to look at argv[], and thusly don't require main() to be present in the IR. This matches GCC's technique where you specify the profiling flag when producing each .o file.

The runtime library is minimal, currently just calling printf at program shutdown time. The API is designed to make it possible to emit GCOV data later on.

llvm-svn: 129340

llvm-svn: 129338

reassociation opportunities are exposed. This fixes a bug where
the nested reassociation expects to be the IR to be consistent,
but it isn't, because the outer reassociation has disconnected
some of the operands.  rdar://9167457

llvm-svn: 129324

llvm-svn: 129319

has some bugs.  If this is interesting functionality, it should be 
reimplemented in the argpromotion pass.

llvm-svn: 129314

mean that it has to be ConstantArray of ConstantStruct. We might have
ConstantAggregateZero, at either level, so don't crash on that.

Also, semi-deprecate the sentinal value. The linker isn't aware of sentinals so
we end up with the two lists appended, each with their "sentinals" on them.
Different parts of LLVM treated sentinals differently, so make them all just
ignore the single entry and continue on with the rest of the list.

llvm-svn: 129307

llvm-svn: 129271

is an array of structures doesn't imply it's a ConstantArray of
ConstantStruct.

llvm-svn: 129207

llvm-svn: 129203