DebugInfo: Implement debug_line.dwo for file names used in type units during -gsplit-dwarf

This removes an attribute (and more importantly, a relocation) from
skeleton type units and removes some unnecessary file names from the
debug_line section that remains in the .o (and linked executable) file.

There's still a few places we could shave off some more space here:

* use compilation dir of the underlying compilation unit (since all the
  type units share that compilation dir - though this would be more
  complicated in LTO cases where they don't (keep a map of compilation
  dir->line table header?))

* Remove some of the unnecessary header fields from the line table since
  they're not needed in this situation (about 12 bytes per table).

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@204099 91177308-0d34-0410-b5e6-96231b3b80d8
DebugInfo: Avoid emitting standard opcode lengths in debug_line.dwo headers where opcodes are never used anyway

Introduce a slightly tighter wrapper around the header structure that
handles this use case. (MCDwarfDwoLineTable)

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@204101 91177308-0d34-0410-b5e6-96231b3b80d8
Shorten DotDebugLocEntry to just DebugLocEntry and reformat.
No functional change.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@204102 91177308-0d34-0410-b5e6-96231b3b80d8
Add explanatory comment.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@204103 91177308-0d34-0410-b5e6-96231b3b80d8
Replace unnecessary #include directive with forward declarations.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@204104 91177308-0d34-0410-b5e6-96231b3b80d8
Switch the type field in DIVariable and DIGlobalVariable over to DITypeRefs.
This allows us to catch more opportunities for ODR-based type uniquing
during LTO.
Paired commit with CFE which updates some testcases to verify the new
DIBuilder behavior.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@204106 91177308-0d34-0410-b5e6-96231b3b80d8
DwarfDebug: Only unique retained types instead of all types.
This is a follow-up to r203983 based on feedback from dblaikie and mren (Thanks!)
No functionality change.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@204107 91177308-0d34-0410-b5e6-96231b3b80d8
ARM: add an assertion

Add an assertion that a valid section is referenced.  The potential NULL pointer
dereference was identified by the clang static analyzer.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@204114 91177308-0d34-0410-b5e6-96231b3b80d8
DebugInfo/lto-comp-dir.ll: Tweak for dos path.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@204117 91177308-0d34-0410-b5e6-96231b3b80d8
CodeGen/R600/v_cndmask.ll: Relax an expression to unbreak msvcrt.

  V_CNDMASK_B32_e64 v0, v0, -1.#QNAN0e+00, s[2:3], 0, 0, 0, 0

FIXME: We really need to implement our formatter...

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@204118 91177308-0d34-0410-b5e6-96231b3b80d8
[C++11] Change the interface of getCOFF{Section,Relocation,Symbol} to make it work with range-based for loops.

Reviewers: ruiu

Reviewed By: ruiu

CC: llvm-commits

Differential Revision: http://llvm-reviews.chandlerc.com/D3097

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@204120 91177308-0d34-0410-b5e6-96231b3b80d8
[C++11] Mark the target fast isel classes as 'final' so that the compiler can de-virtualize some of the internal calls.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@204123 91177308-0d34-0410-b5e6-96231b3b80d8
[msan] Remove unused code.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@204125 91177308-0d34-0410-b5e6-96231b3b80d8
[C++11] Change DebugInfoFinder to use range-based loops

Also changes the iterators to return actual DI type over MDNode.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@204130 91177308-0d34-0410-b5e6-96231b3b80d8
[msan] Kill -msan-store-clean-origin flag.

Not only is it slower than the alternative, but also subtly broken.
This commit does not change the default behavior.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@204131 91177308-0d34-0410-b5e6-96231b3b80d8
DebugIRTests: Fixup for r204130.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@204132 91177308-0d34-0410-b5e6-96231b3b80d8
Add IAS/EHABI changes to release notes

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@204134 91177308-0d34-0410-b5e6-96231b3b80d8
Revert r203962 and two revisions depending on it: r204028 and r204059.
The revision I'm reverting breaks handling of transitive aliases. This blocks us
and breaks sanitizer bootstrap:
http://lab.llvm.org:8011/builders/sanitizer-x86_64-linux-bootstrap/builds/2651
(and checked locally by Alexey).

This revision is the result of:

  svn merge -r204059:204058 -r204028:204027 -r203962:203961 .

+ the regression test added to test/MC/ELF/alias.s

Another way to reproduce the regression with clang:
  $ cat q.c
  void a1();
  void a2() __attribute__((alias("a1")));
  void a3() __attribute__((alias("a2")));
  void a1() {}

  $ ~/work/llvm-build/bin/clang-3.5-good -c q.c && mv q.o good.o && \
      ~/work/llvm-build/bin/clang-3.5-bad -c q.c && mv q.o bad.o && \
      objdump -t good.o bad.o

    good.o:     file format elf64-x86-64

    SYMBOL TABLE:
    0000000000000000 l    df *ABS*  0000000000000000 q.c
    0000000000000000 l    d  .text  0000000000000000 .text
    0000000000000000 l    d  .data  0000000000000000 .data
    0000000000000000 l    d  .bss   0000000000000000 .bss
    0000000000000000 l    d  .comment       0000000000000000 .comment
    0000000000000000 l    d  .note.GNU-stack        0000000000000000 .note.GNU-stack
    0000000000000000 l    d  .eh_frame      0000000000000000 .eh_frame
    0000000000000000 g     F .text  0000000000000006 a1
    0000000000000000 g     F .text  0000000000000006 a2
    0000000000000000 g     F .text  0000000000000006 a3



    bad.o:     file format elf64-x86-64

    SYMBOL TABLE:
    0000000000000000 l    df *ABS*  0000000000000000 q.c
    0000000000000000 l    d  .text  0000000000000000 .text
    0000000000000000 l    d  .data  0000000000000000 .data
    0000000000000000 l    d  .bss   0000000000000000 .bss
    0000000000000000 l    d  .comment       0000000000000000 .comment
    0000000000000000 l    d  .note.GNU-stack        0000000000000000 .note.GNU-stack
    0000000000000000 l    d  .eh_frame      0000000000000000 .eh_frame
    0000000000000000 g     F .text  0000000000000006 a1
    0000000000000000 g     F .text  0000000000000006 a2
    0000000000000000 g       .text  0000000000000000 a3




git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@204137 91177308-0d34-0410-b5e6-96231b3b80d8
Tolerate unmangled names in sample profiles.

Summary:
The compiler does not always generate linkage names. If a function
has been inlined and its body elided, its linkage name may not be
generated.

When the binary executes, the profiler will use its unmangled name
when attributing samples. This results in unmangled names in the
input profile.

We are currently failing hard when this happens. However, in this case
all that happens is that we fail to attribute samples to the inlined
function. While this means fewer optimization opportunities, it should
not cause a compilation failure.

This patch accepts all valid function names, regardless of whether
they were mangled or not.

Reviewers: chandlerc

CC: llvm-commits

Differential Revision: http://llvm-reviews.chandlerc.com/D3087

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@204142 91177308-0d34-0410-b5e6-96231b3b80d8
[msan] Origin tracking with history.

LLVM part of MSan implementation of advanced origin tracking,
when we record not only creation point, but all locations where
an uninitialized value was stored to memory, too.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@204151 91177308-0d34-0410-b5e6-96231b3b80d8