Fix ScalarEvolution::ComputeExitLimitFromCond for 'or' conditions.

Fixes PR16130 - clang produces incorrect code with loop/expression at -O2.

This is a 2+ year old bug that's now holding up the release. It's a
case where we knowingly made aggressive assumptions about undefined
behavior. These assumptions are wrong when SCEV is computing a
subexpression that does not directly control the branch. With this
fix, we avoid making assumptions in those cases but still optimize the
common case. SCEV's trip count computation for exits controlled by
'or' expressions is now analagous to the trip count computation for
loops with multiple exits. I had already fixed the multiple exit case
to be conservative.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@182989 91177308-0d34-0410-b5e6-96231b3b80d8
Add links to the System z architecture manual and ABI


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@182990 91177308-0d34-0410-b5e6-96231b3b80d8
X86: change MOV64ri64i32 into MOV32ri64

The MOV64ri64i32 instruction required hacky MCInst lowering because it was
allocated as setting a GR64, but the eventual instruction ("movl") only set a
GR32. This converts it into a so-called "MOV32ri64" which still accepts a
(appropriate) 64-bit immediate but defines a GR32. This is then converted to
the full GR64 by a SUBREG_TO_REG operation, thus keeping everyone happy.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@182991 91177308-0d34-0410-b5e6-96231b3b80d8
[msan] Handle mixed track-origins and keep-going settings (llvm part).

Before this change, each module defined a weak_odr global __msan_track_origins 
with a value of 1 if origin tracking is enabled, 0 if disabled. If there are 
modules with different values, any of them may win. If 0 wins, and there is at 
least one module with 1, the program will most likely crash.

With this change, __msan_track_origins is only emitted if origin tracking is 
on. Then runtime library detects if there is at least one module with origin 
tracking, and enables runtime support for it.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@182997 91177308-0d34-0410-b5e6-96231b3b80d8
[NVPTX] Re-enable support for virtual registers in the final output

Now that 3.3 is branched, we are re-enabling virtual registers to help
iron out bugs before the next release. Some of the post-RA passes do
not play well with virtual registers, so we disable them for now. The
needed functionality of the PrologEpilogInserter pass is copied to a
new backend-specific NVPTXPrologEpilog pass.

The test for this commit is not breaking the existing tests.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@182998 91177308-0d34-0410-b5e6-96231b3b80d8
[SystemZ] Don't use LOAD and STORE REVERSED for volatile accesses

Unlike most -- hopefully "all other", but I'm still checking -- memory
instructions we support, LOAD REVERSED and STORE REVERSED may access
the memory location several times.  This means that they are not suitable
for volatile loads and stores.

This patch is a prerequisite for better atomic load and store support.
The same principle applies there: almost all memory instructions we
support are inherently atomic ("block concurrent"), but LOAD REVERSED
and STORE REVERSED are exceptions.

Other instructions continue to allow volatile operands.  I will add
positive "allows volatile" tests at the same time as the "allows atomic
load or store" tests.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@183002 91177308-0d34-0410-b5e6-96231b3b80d8
ARM: fix VEXT encoding corner case

The disassembly of VEXT instructions was too lax in the bits checked. This
fixes the case where the instruction affects Q-registers but a misaligned lane
was specified (should be UNDEFINED).

Patch by Amaury de la Vieuville

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@183003 91177308-0d34-0410-b5e6-96231b3b80d8
Simplify multiplications by vectors whose elements are powers of 2.

Patch by Andrea Di Biagio.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@183005 91177308-0d34-0410-b5e6-96231b3b80d8
ARM: add fstmx and fldmx instructions for assembly

These instructions are deprecated oddities, but we still need to be able to
disassemble (and reassemble) them if and when they're encountered.

Patch by Amaury de la Vieuville.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@183011 91177308-0d34-0410-b5e6-96231b3b80d8
ARM: permit upper-case BE/LE on setend instruction

Patch by Amaury de la Vieuville.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@183012 91177308-0d34-0410-b5e6-96231b3b80d8
Remove useless code from transitioning to new EH scheme

Removes all uses of the variable UsesNewEH. Simply return false in case that no
resume instructions were found.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@183016 91177308-0d34-0410-b5e6-96231b3b80d8
Unit test for SCEV fix r182989, PR16130.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@183017 91177308-0d34-0410-b5e6-96231b3b80d8
Add a way to define the bit range covered by a SubRegIndex.

NOTE: If this broke your out-of-tree backend, in *RegisterInfo.td, change
the instances of SubRegIndex that have a comps template arg to use the
ComposedSubRegIndex class instead.

In TableGen land, this adds Size and Offset attributes to SubRegIndex,
and the ComposedSubRegIndex class, for which the Size and Offset are
computed by TableGen. This also adds an accessor in MCRegisterInfo, and
Size/Offsets for the X86 and ARM subreg indices.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@183020 91177308-0d34-0410-b5e6-96231b3b80d8
Modify how the formulae are rated in Loop Strength Reduce.
Namely, check if the target allows to fold more that one register in the
addressing mode and if yes, adjust the cost accordingly.

Prior to this commit, reg1 + scale * reg2 accesses were artificially preferred
to reg1 + reg2 accesses. Indeed, the cost model wrongly assumed that reg1 + reg2
needs a temporary register for the computation, whereas it was correctly
estimated for reg1 + scale * reg2.

<rdar://problem/13973908>


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@183021 91177308-0d34-0410-b5e6-96231b3b80d8
[APFloat] Added a unittest for APFloat::getZero.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@183028 91177308-0d34-0410-b5e6-96231b3b80d8
NVPTX: Don't even create a regalloc if we're not going to use it.

Fixes a leak found by valgrind.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@183031 91177308-0d34-0410-b5e6-96231b3b80d8
LoopVectorize: PHIs with only outside users should prevent vectorization

We check that instructions in the loop don't have outside users (except if
they are reduction values). Unfortunately, we skipped this check for
if-convertable PHIs.

Fixes PR16184.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@183035 91177308-0d34-0410-b5e6-96231b3b80d8
Don't allocate temporary string for section data.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@183040 91177308-0d34-0410-b5e6-96231b3b80d8
Remove union to fix build in c++03.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@183041 91177308-0d34-0410-b5e6-96231b3b80d8
Rename COFFYaml.h to COFFYAML.h for consistency.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@183042 91177308-0d34-0410-b5e6-96231b3b80d8