[FastISel][AArch64] Use 'cbz' also for null values (pointers).

The pattern matching for a 'ConstantInt' value was too restrictive. Checking for
a 'Constant' with a bull value is sufficient for using an 'cbz/cbnz' instruction.

This fixes rdar://problem/18784732.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@220709 91177308-0d34-0410-b5e6-96231b3b80d8
Stackmap shadows should consider call returns a branch target.

To avoid emitting too many nops, a stackmap shadow can include emitted instructions in the shadow, but these must not include branch targets.

A return from a call should count as a branch target as patching over the instructions after the call would lead to incorrect behaviour for threads currently making that call, when they return.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@220710 91177308-0d34-0410-b5e6-96231b3b80d8
[FastISel][AArch64] Optimize compare-and-branch for i1 to use 'tbz'.

Minor enhancement to use 'tbz' for i1 compare-and-branch to get rid of an 'and'
instruction.

This fixes rdar://problem/18784953.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@220712 91177308-0d34-0410-b5e6-96231b3b80d8
[FastISel][AArch64] Emit immediate version of icmp (subs) for null pointer check.

This is a minor change to use the immediate version when the operand is a null
value. This should get rid of an unnecessary 'mov' instruction in debug
builds and align the code more with the one generated by SelectionDAG.

This fixes rdar://problem/18785125.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@220713 91177308-0d34-0410-b5e6-96231b3b80d8
Fix bug where sys::Wait could wait on wrong pid.

Setting ChildPid to -1 would cause waitpid to wait for any child process.

Patch by Daniel Reynaud!

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@220717 91177308-0d34-0410-b5e6-96231b3b80d8
[ScalarEvolution] Guard dump() with #if

to be consistent with its definition in ScalarEvolution.cpp


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@220721 91177308-0d34-0410-b5e6-96231b3b80d8
Fix a stackmap bug introduced in r220710.

For a call to not return in to the stackmap shadow, the shadow must end with the call.

To do this, we must insert any required nops *before* the call, and not after it.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@220728 91177308-0d34-0410-b5e6-96231b3b80d8
Make it easier to pass a custom diagnostic handler to the IR linker.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@220732 91177308-0d34-0410-b5e6-96231b3b80d8
[AVX512] Fix copy-and-paste bugs in vpermil

1) i512mem -> f512mem (this is the packed FP input being permuted)
2) element size is 64 bits in EVEX_CD8 for PD.

(A good illustration why X86VectorVTInfo is useful)

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@220734 91177308-0d34-0410-b5e6-96231b3b80d8
[AVX512] Derive vpermil* from avx512_perm_imm

This used to derive from avx512_pshuf_imm which is confusing.

NFC.  Compared X86.td.expanded.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@220735 91177308-0d34-0410-b5e6-96231b3b80d8
[AVX512] Clean up avx512_perm_imm to use X86VectorVTInfo

No functionality change.  No change in X86.td.expanded except that we only set
the CD8 attributes for the memory variants.  (This shouldn't be used unless we
have a memory operand.)

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@220736 91177308-0d34-0410-b5e6-96231b3b80d8
[AVX512] Add vpermil variable version

This is implemented via a multiclass that derives from the vperm imm
multiclass.

Fixes <rdar://problem/18426089>

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@220737 91177308-0d34-0410-b5e6-96231b3b80d8
AArch64InstrInfo.h: Fix a warning introduced in clang r220703. [-Winconsistent-missing-override]

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@220739 91177308-0d34-0410-b5e6-96231b3b80d8
Remove the PreserveSource linker mode.

I noticed that it was untested, and forcing it on caused some tests to fail:

    LLVM :: Linker/metadata-a.ll
    LLVM :: Linker/prefixdata.ll
    LLVM :: Linker/type-unique-odr-a.ll
    LLVM :: Linker/type-unique-simple-a.ll
    LLVM :: Linker/type-unique-simple2-a.ll
    LLVM :: Linker/type-unique-simple2.ll
    LLVM :: Linker/type-unique-type-array-a.ll
    LLVM :: Linker/unnamed-addr1-a.ll
    LLVM :: Linker/visibility1.ll

If it is to be resurrected, it has to be fixed and we should probably have a
-preserve-source command line option in llvm-mc and run tests with and without
it.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@220741 91177308-0d34-0410-b5e6-96231b3b80d8
AArch64: enable Cortex-A57 FP balancing on Cortex-A53.

Benchmarks have shown that it's harmless to the performance there, and having a
unified set of passes between the two cores where possible helps big.LITTLE
deployment.

Patch by Z. Zheng.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@220744 91177308-0d34-0410-b5e6-96231b3b80d8
X86: Implement the vectorcall calling convention

This is a Microsoft calling convention that supports both x86 and x86_64
subtargets. It passes vector and floating point arguments in XMM0-XMM5,
and passes them indirectly once they are consumed.

Homogenous vector aggregates of up to four elements can be passed in
sequential vector registers, but this part is not implemented in LLVM
and will be handled in Clang.

On 32-bit x86, it is similar to fastcall in that it uses ecx:edx as
integer register parameters and is callee cleanup. On x86_64, it
delegates to the normal win64 calling convention.

Reviewers: majnemer

Differential Revision: http://reviews.llvm.org/D5943

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@220745 91177308-0d34-0410-b5e6-96231b3b80d8
Minimize the scope of some variables, NFC.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@220759 91177308-0d34-0410-b5e6-96231b3b80d8