Adjust test case addition in r218702 so as not to fail when the X86 target isn't built.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@218708 91177308-0d34-0410-b5e6-96231b3b80d8
[x86] Update the exact FileCheck syntax of the 256-bit and 512-bit
shuffle tests to match that used in the script I posted and now used
consistently in 128-bit tests.

Nothing interesting changing here, just using the label name as the
FileCheck label and a slightly more general comment marker consumption
strategy.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@218709 91177308-0d34-0410-b5e6-96231b3b80d8
[x86] Add AVX1 and AVX2 testing to all of the 128-bit shuffle test
cases.

While clearly we don't need the AVX vector width, these ISA extensions
often cause us to select different instructions and we should cover them
even with the narrow vector width.

Also, while here, nuke the stress_test2 contents. There is no reason to
try to FileCheck this entire body when it is mostly a test for
successfully surviving the code generator.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@218710 91177308-0d34-0410-b5e6-96231b3b80d8
[SimplifyCFG] threshold for folding branches with common destination

Summary:
This patch adds a threshold that controls the number of bonus instructions
allowed for folding branches with common destination. The original code allows
at most one bonus instruction. With this patch, users can customize the
threshold to allow multiple bonus instructions. The default threshold is still
1, so that the code behaves the same as before when users do not specify this
threshold.

The motivation of this change is that tuning this threshold significantly (up
to 25%) improves the performance of some CUDA programs in our internal code
base. In general, branch instructions are very expensive for GPU programs.
Therefore, it is sometimes worth trading more arithmetic computation for a more
straightened control flow. Here's a reduced example:

  __global__ void foo(int a, int b, int c, int d, int e, int n,
                      const int *input, int *output) {
    int sum = 0;
    for (int i = 0; i < n; ++i)
      sum += (((i ^ a) > b) && (((i | c ) ^ d) > e)) ? 0 : input[i];
    *output = sum;
  }

The select statement in the loop body translates to two branch instructions "if
((i ^ a) > b)" and "if (((i | c) ^ d) > e)" which share a common destination.
With the default threshold, SimplifyCFG is unable to fold them, because
computing the condition of the second branch "(i | c) ^ d > e" requires two
bonus instructions. With the threshold increased, SimplifyCFG can fold the two
branches so that the loop body contains only one branch, making the code
conceptually look like:

  sum += (((i ^ a) > b) & (((i | c ) ^ d) > e)) ? 0 : input[i];

Increasing the threshold significantly improves the performance of this
particular example. In the configuration where both conditions are guaranteed
to be true, increasing the threshold from 1 to 2 improves the performance by
18.24%. Even in the configuration where the first condition is false and the
second condition is true, which favors shortcuts, increasing the threshold from
1 to 2 still improves the performance by 4.35%.

We are still looking for a good threshold and maybe a better cost model than
just counting the number of bonus instructions. However, according to the above
numbers, we think it is at least worth adding a threshold to enable more
experiments and tuning. Let me know what you think. Thanks!

Test Plan: Added one test case to check the threshold is in effect

Reviewers: nadav, eliben, meheff, resistor, hfinkel

Reviewed By: hfinkel

Subscribers: hfinkel, llvm-commits

Differential Revision: http://reviews.llvm.org/D5529

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@218711 91177308-0d34-0410-b5e6-96231b3b80d8
MSBuild integration: fix the loop in install.bat

It would previously not continue the platforms loop
unless it could find the latest toolset directory.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@218712 91177308-0d34-0410-b5e6-96231b3b80d8
DebugInfo: Sink the code emitting DW_AT_APPLE_omit_frame_ptr down to a more common spot.

No functional change. Pre-emptive refactoring before I start pushing
some of this subprogram creation down into DWARFCompileUnit so I can
build different subprograms in the skeleton unit from the dwo unit for
adding -gmlt-like data to the skeleton.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@218713 91177308-0d34-0410-b5e6-96231b3b80d8
[BasicAA] Make better use of zext and sign information

Two related things:

 1. Fixes a bug when calculating the offset in GetLinearExpression. The code
    previously used zext to extend the offset, so negative offsets were converted
    to large positive ones.

 2. Enhance aliasGEP to deduce that, if the difference between two GEP
    allocations is positive and all the variables that govern the offset are also
    positive (i.e. the offset is strictly after the higher base pointer), then
    locations that fit in the gap between the two base pointers are NoAlias.

Patch by Nick White!

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@218714 91177308-0d34-0410-b5e6-96231b3b80d8
Omit DW_AT_inline under -gmlt to save a little more space.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@218719 91177308-0d34-0410-b5e6-96231b3b80d8
[InstCombine] Optimize icmp-select-icmp

In special cases select instructions can be eliminated by
replacing them with a cheaper bitwise operation even when the
select result is used outside its home block. The instances implemented
are patterns like
    %x=icmp.eq
    %y=select %x,%r, null
    %z=icmp.eq|neq %y, null
    br %z,true, false
==> %x=icmp.ne
    %y=icmp.eq %r,null
    %z=or %x,%y
    br %z,true,false
The optimization is integrated into the instruction
combiner and performed only when all uses of the select result can
be replaced by the select operand proper. For this dominator information
is used and dominance is now a required analysis pass in the combiner.
The optimization itself is iterative. The critical step is to replace the
select result with the non-constant select operand. So the select becomes
local and the combiner iteratively works out simpler code pattern and
eventually eliminates the select.

rdar://17853760



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@218721 91177308-0d34-0410-b5e6-96231b3b80d8
llvm/test/DebugInfo/X86/gmlt.test: Get rid of %llc_dwarf. It should not be used with -mtriple.

Also, remove object-emission. test/DebugInfo/X86 doesn't require it.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@218722 91177308-0d34-0410-b5e6-96231b3b80d8
llvm-cov/CoverageReport.cpp: Quick fix for msvcrt, since width specifier "z" is unavailable.

Note, mingw uses its own printf instead of msvcrt.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@218723 91177308-0d34-0410-b5e6-96231b3b80d8
[x86] Teach the new vector shuffle lowering about VBROADCAST and
VPBROADCAST.

This has the somewhat expected pervasive impact. I don't know why
I forgot about this. Everything seems good with lots of significant
improvements in the tests.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@218724 91177308-0d34-0410-b5e6-96231b3b80d8
[AVX512] Remove space before \t in AsmStrings.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@218725 91177308-0d34-0410-b5e6-96231b3b80d8
Implement DW_TAG_subrange_type with DW_AT_count rather than DW_AT_upper_bound

This allows proper disambiguation of unbounded arrays and arrays of zero
bound ("struct foo { int x[]; };" and "struct foo { int x[0]; }"). GCC
instead produces an upper bound of -1 in the latter situation, but count
seems tidier. This way lower_bound is provided if it's not the language
default and count is provided if the count is known, otherwise it's
omitted. Simple.

If someone wants to look at rdar://problem/12566646 and see if this
change is acceptable to that bug/fix, that might be helpful (see the
empty-and-one-elem-array.ll test case which cites that radar).

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@218726 91177308-0d34-0410-b5e6-96231b3b80d8
Add an emplace(...) method to llvm::Optional<T>.

This can be used for in-place initialization of non-moveable types.
For compilers that don't support variadic templates, only up to four
arguments are supported. We can always add more, of course, but this
should be good enough until we move to a later MSVC that has full
support for variadic templates.

Inspired by std::experimental::optional from the "Library Fundamentals" C++ TS.
Reviewed by David Blaikie.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@218732 91177308-0d34-0410-b5e6-96231b3b80d8
[x86] Hoist the zext-lowering up in the v4i32 lowering routine -- it is
the same speed as pshufd but we can fold loads into the pmovzx
instructions.

This fixes some regressions that came up in the regression test suite
for the new vector shuffle lowering.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@218733 91177308-0d34-0410-b5e6-96231b3b80d8
[x86] Teach the new vector shuffle lowering to be even more aggressive
in exposing the scalar value to the broadcast DAG fragment so that we
can catch even reloads and fold them into the broadcast.

This is somewhat magical I'm afraid but seems to work. It is also what
the old lowering did, and I've switched an old test to run both
lowerings demonstrating that we get the same result.

Unlike the old code, I'm not lowering f32 or f64 scalars through this
path when we only have AVX1. The target patterns include pretty heinous
code to re-cast those as shuffles when the scalar happens to not be
spilled because AVX1 provides no broadcast mechanism from registers
what-so-ever. This is terribly brittle. I'd much rather go through our
generic lowering code to get this. If needed, we can add a peephole to
get even more opportunities to broadcast-from-spill-slots that are
exposed post-RA, but my suspicion is this just doesn't matter that much.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@218734 91177308-0d34-0410-b5e6-96231b3b80d8
[InstCombine] Fix for assert build failures caused by r218721

The icmp-select-icmp optimization made the implicit assumption
that the select-icmp instructions are in the same block and asserted on it.
The fix explicitly checks for that condition and conservatively suppresses
the optimization when it is violated.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@218735 91177308-0d34-0410-b5e6-96231b3b80d8
InstrProf: Make coverage::Counter comparable

I'll be using this in a clang change very soon.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@218736 91177308-0d34-0410-b5e6-96231b3b80d8
Fix typo in comment from r218733


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@218739 91177308-0d34-0410-b5e6-96231b3b80d8