[C++11] Add range based accessors for the Use-Def chain of a Value.

This requires a number of steps.
1) Move value_use_iterator into the Value class as an implementation
   detail
2) Change it to actually be a *Use* iterator rather than a *User*
   iterator.
3) Add an adaptor which is a User iterator that always looks through the
   Use to the User.
4) Wrap these in Value::use_iterator and Value::user_iterator typedefs.
5) Add the range adaptors as Value::uses() and Value::users().
6) Update *all* of the callers to correctly distinguish between whether
   they wanted a use_iterator (and to explicitly dig out the User when
   needed), or a user_iterator which makes the Use itself totally
   opaque.

Because #6 requires churning essentially everything that walked the
Use-Def chains, I went ahead and added all of the range adaptors and
switched them to range-based loops where appropriate. Also because the
renaming requires at least churning every line of code, it didn't make
any sense to split these up into multiple commits -- all of which would
touch all of the same lies of code.

The result is still not quite optimal. The Value::use_iterator is a nice
regular iterator, but Value::user_iterator is an iterator over User*s
rather than over the User objects themselves. As a consequence, it fits
a bit awkwardly into the range-based world and it has the weird
extra-dereferencing 'operator->' that so many of our iterators have.
I think this could be fixed by providing something which transforms
a range of T&s into a range of T*s, but that *can* be separated into
another patch, and it isn't yet 100% clear whether this is the right
move.

However, this change gets us most of the benefit and cleans up
a substantial amount of code around Use and User. =]

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@203364 91177308-0d34-0410-b5e6-96231b3b80d8
Fix build break.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@203366 91177308-0d34-0410-b5e6-96231b3b80d8
[C++11] Fix break due to MSVC bug.

MSVC (2012, 2013, 2013 Nov CTP) fail on the following code:

int main() {
  int arr[] = {1, 2};
  for (int i : arr)
    do {} while (0);
}

The fix is to put {} around the for loop. I've reported this to the MSVC
team.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@203371 91177308-0d34-0410-b5e6-96231b3b80d8
Clean up SmallString a bit

Move a common utility (assign(iter, iter)) into SmallVector (some of the
others could be moved there too, but this one seemed particularly
generic) and replace repetitions overrides with using directives.

And simplify SmallVector::assign(num, element) while I'm here rather
than thrashing these files (that cause everyone to rebuild) again.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@203374 91177308-0d34-0410-b5e6-96231b3b80d8
Revert "Clean up SmallString a bit"

This reverts commit r203374.

Ambiguities in assign... oh well. I'm just going to revert this and
probably not try to recommit it as it's not terribly important.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@203375 91177308-0d34-0410-b5e6-96231b3b80d8
IR: Change inalloca's grammar a bit

The grammar for LLVM IR is not well specified in any document but seems
to obey the following rules:

 - Attributes which have parenthesized arguments are never preceded by
   commas.  This form of attribute is the only one which ever has
   optional arguments.  However, not all of these attributes support
   optional arguments: 'thread_local' supports an optional argument but
   'addrspace' does not.  Interestingly, 'addrspace' is documented as
   being a "qualifier".  What constitutes a qualifier?  I cannot find a
   definition.

 - Some attributes use a space between the keyword and the value.
   Examples of this form are 'align' and 'section'.  These are always
   preceded by a comma.

 - Otherwise, the attribute has no argument.  These attributes do not
   have a preceding comma.

Sometimes an attribute goes before the instruction, between the
instruction and it's type, or after it's type.  'atomicrmw' has
'volatile' between the instruction and the type while 'call' has 'tail'
preceding the instruction.

With all this in mind, it seems most consistent for 'inalloca' on an
'inalloca' instruction to occur before between the instruction and the
type.  Unlike the current formulation, there would be no preceding
comma.  The combination 'alloca inalloca' doesn't look particularly
appetizing, perhaps a better spelling of 'inalloca' is down the road.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@203376 91177308-0d34-0410-b5e6-96231b3b80d8
[C++11] Add 'override' keyword to virtual methods that override their base class.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@203378 91177308-0d34-0410-b5e6-96231b3b80d8
De-virtualize some methods since they don't override anything.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@203379 91177308-0d34-0410-b5e6-96231b3b80d8
Revert r203230, "CodeGenPrep: sink extends of illegal types into use block."

It choked i686 stage2.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@203386 91177308-0d34-0410-b5e6-96231b3b80d8
[C++11] Add llvm::make_unique, according to N3656.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@203387 91177308-0d34-0410-b5e6-96231b3b80d8
[PM] Switch new pass manager from polymorphic_ptr to unique_ptr now that
it is available. Also make the move semantics sufficiently correct to
tolerate move-only passes, as the PassManagers *are* move-only passes.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@203391 91177308-0d34-0410-b5e6-96231b3b80d8
[C++11] Now that we have C++11 and I've replaced the use of this
horrible smart pointer by std::unique_ptr and strict move semantics, rip
this out.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@203392 91177308-0d34-0410-b5e6-96231b3b80d8
Change documentation based on feedback from Chandler.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@203393 91177308-0d34-0410-b5e6-96231b3b80d8
[C++11] Add range views for various parts of a Module.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@203394 91177308-0d34-0410-b5e6-96231b3b80d8
[LCG] Simplify a bunch of the LCG code with range for loops and auto.
Still more work to be done here to leverage C++11, but this clears out
the glaring issues.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@203395 91177308-0d34-0410-b5e6-96231b3b80d8
SimplifyCFG: Simplify the weight scaling algorithm.

No change in functionality.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@203413 91177308-0d34-0410-b5e6-96231b3b80d8
MachineModuleInfo: Turn nested std::pairs into a proper struct.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@203414 91177308-0d34-0410-b5e6-96231b3b80d8
StackColoring: Use range-based for loops.

No functionality change.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@203415 91177308-0d34-0410-b5e6-96231b3b80d8
[C++11] Add 'override' keyword to virtual methods that override their base class.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@203418 91177308-0d34-0410-b5e6-96231b3b80d8
Work around FreeBSD rtld rpath $ORIGIN limitation

FreeBSD's rtld requires the DF_ORIGIN flag set in order to process
$ORIGIN in rpath.

FreeBSD bug http://bugs.freebsd.org/187114


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@203419 91177308-0d34-0410-b5e6-96231b3b80d8