Fixed a bug in lowering shuffle_vectors to insertps

Summary:
We were being too strict and not accounting for undefs.
Added a test case and fixed another one where we improved codegen.

Reviewers: grosbach, nadav, delena

Subscribers: llvm-commits

Differential Revision: http://reviews.llvm.org/D4039

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@210361 91177308-0d34-0410-b5e6-96231b3b80d8
Remove DWARF3 testing of test/DebugInfo/X86/gnu-public-names.ll

This was added to test that DW_AT_GNU_pubnames used sec_offset in DWARF4
and data4 in DWARF3 and below. Since then we've updated
DW_AT_GNU_pubnames to be a flag, rather than a section offset anyway.

Granted this still differs between DWARF 3 and DWARF 4
(FORM_flag_present versun FORM_flag) but it doesn't seem worthwhile
testing that codepath again here. It's covered adequately in many other
test cases.

And while I'm here, don't hardcode the byte size of the compile unit -
it's not relevant to this test and just makes it brittle if/when
anything changes in the way this CU is emitted.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@210362 91177308-0d34-0410-b5e6-96231b3b80d8
Fix a typo made in Programmer's Manual made in r210354. Spotted
by Paul Robinson.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@210363 91177308-0d34-0410-b5e6-96231b3b80d8
Match the full hex offsets in test/DebugInfo/X86/gnu-public-names.ll

These checks were accidentally skipping the 0x prefix in the hex
offsets, then cunningly ignoring the prefix in the use of those captured
values.

Except in the case of the unit length, where the match was only matching
the leading '0' before the x in the 0x prefix, then matching that
against the length. We can't actually express the length association
here, as the length field in the Compile Unit header does not include
the length field itself, but the length field in the pubnames section
/does/ include the size of the length field in the Compile Unit header -
so the two numbers are actually 4 bytes different. Just skip matching
that.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@210364 91177308-0d34-0410-b5e6-96231b3b80d8