part of simplifying its interface and usage in preparation for porting
to work with the new pass manager.

Note that this will likely expose that we have dead arguments, members,
and maybe even pass requirements for AA. I'll be cleaning those up in
seperate patches. This just zaps the actual update API.

Differential Revision: http://reviews.llvm.org/D11325

llvm-svn: 242881

change because the diff is *useless*. I assure you, I just switched to
early-return in this function.

Cleanup in preparation for my next commit, as requested in code review!

llvm-svn: 242880

succeed at compiling my change before committing it too!

llvm-svn: 242879

GlobalsModRef) with CallbackVHs that trigger the same behavior.

This is technically more expensive, but in benchmarking some LTO runs,
it seems unlikely to even be above the noise floor. The only way I was
able to measure the performance of GMR at all was to run nothing else
but this one analysis on a linked clang bitcode file. The call graph
analysis still took 5x more time than GMR, and this change at most made
GMR 2% slower (this is well within the noise, so its hard for me to be
sure that this is an actual change). However, in a real LTO run over the
same bitcode, the GMR run takes so little time that the pass timers
don't measure it.

With this, I can remove the last update API from the AliasAnalysis
interface, but I'll actually remove the interface hook point in
a follow-up commit.

Differential Revision: http://reviews.llvm.org/D11324

llvm-svn: 242878

All SKX forms. All VCVT instructions for float/double/int/long types.

Differential Revision: http://reviews.llvm.org/D11343

llvm-svn: 242877

[LoopUnswitch] Code refactoring to separate trivial loop unswitch and non-trivial loop unswitch in processCurrentLoop()

Summary: The current code in LoopUnswtich::processCurrentLoop() mixes trivial loop unswitch and non-trivial loop unswitch together. It goes over all basic blocks in the loop and checks if a condition is trivial or non-trivial unswitch condition. However, trivial unswitch condition can only occur in the loop header basic block (where it controls whether or not the loop does something at all). This refactoring separate trivial loop unswitch and non-trivial loop unswitch. Before going over all basic blocks in the loop, it checks if the loop header contains a trivial unswitch condition. If so, unswitch it. Otherwise, go over all blocks like before but don't check trivial condition any more since they are not possible to be in the other blocks. This code has no functionality change.

Reviewers: meheff, reames, broune

Subscribers: llvm-commits

Differential Revision: http://reviews.llvm.org/D11276

llvm-svn: 242873

Summary:
MCRegAliasIterator only works for physical registers. So, do not run it
on virtual registers.

With this issue fixed, we can resurrect the BranchFolding pass in NVPTX
backend.

Reviewers: jholewinski, bkramer

Subscribers: henryhu, meheff, llvm-commits, jholewinski

Differential Revision: http://reviews.llvm.org/D11174

llvm-svn: 242871

types and loads, loads or stores widened past the size of an alloca,
etc.

This started off with a bug report about big-endian behavior with
bitfields and loads and stores to a { i32, i24 } struct. An initial
attempt to fix this was sent for review in D10357, but that didn't
really get to the root of the problem.

The core issue was that canConvertValue and convertValue in SROA were
handling different bitwidth integers by doing a zext of the integer. It
wouldn't do a trunc though, only a zext! This would in turn lead SROA to
form an i24 load from an i24 alloca, zext it to i32, and then use it.
This would at least produce the wrong value for big-endian systems.

One of my many false starts here was to correct the computation for
big-endian systems by shifting. But this doesn't actually work because
the original code has a 64-bit store to the entire 8 bytes, and a 32-bit
load of the last 4 bytes, and because the alloc size is 8 bytes, we
can't lose that last (least significant if bigendian) byte! The real
problem here is that we're forming an i24 load in SROA which is actually
not sufficiently wide to load all of the necessary bits here. The source
has an i32 load, and SROA needs to form that as well.

The straightforward way to do this is to disable the zext logic in
canConvertValue and convertValue, forcing us to actually load all
32-bits. This seems like a really good change, but it in turn breaks
several other parts of SROA.

First in the chain of knock-on failures, we had places where we were
doing integer-widening promotion even though some of the integer loads
or stores extended *past the end* of the alloca's memory! There was even
a comment about preventing this, but it only prevented the case where
the type had a different bit size from its store size. So I added checks
to handle the cases where we actually have a widened load or store and
to avoid trying to special integer widening promotion in those cases.

Second, we actually rely on the ability to promote in the face of loads
past the end of an alloca! This is important so that we can (for
example) speculate loads around PHI nodes to do more promotion. The bits
loaded are garbage, but as long as they aren't used and the alignment is
suitable high (which it wasn't in the test case!) this is "fine". And we
can't stop promoting here, lots of things stop working well if we do. So
we need to add specific logic to handle the extension (and truncation)
case, but *only* where that extension or truncation are over bytes that
*are outside the alloca's allocated storage* and thus totally bogus to
load or store.

And of course, once we add back this correct handling of extension or
truncation, we need to correctly handle bigendian systems to avoid
re-introducing the exact bug that started us off on this chain of misery
in the first place, but this time even more subtle as it only happens
along speculated loads atop a PHI node.

I've ported an existing test for PHI speculation to the big-endian test
file and checked that we get that part correct, and I've added several
more interesting big-endian test cases that should help check that we're
getting this correct.

Fun times.

llvm-svn: 242869

llvm-svn: 242865

llvm-svn: 242851

llvm-svn: 242850

This optimization allows the DWARF linker to reuse definition of
types it has emitted in previous CUs rather than reemitting them
in each CU that references them. The size and link time gains are
huge. For example when linking the DWARF for a debug build of
clang, this generates a ~150M dwarf file instead of a ~700M one
(the numbers date back a bit and must not be totally accurate
these days).

As with all the other parts of the llvm-dsymutil codebase, the
goal is to keep bit-for-bit compatibility with dsymutil-classic.
The code is littered with a lot of FIXMEs that should be
addressed once we can get rid of the compatibilty goal.

llvm-svn: 242847

This commit begins serialization of the CFI index machine operands by
serializing one kind of CFI instruction - the .cfi_def_cfa_offset instruction.

Reviewers: Duncan P. N. Exon Smith
llvm-svn: 242845

Fix a performance problem in memcpyopt by removing a linear scan over ranges when inserting a new range. No functionality change intended. Patch by Anthony Pesch!

llvm-svn: 242843

Summary:
In the benchmark (https://github.com/vetter/shoc) we are researching,
the duplicated load is not eliminated because MemoryDependenceAnalysis
hit the BlockScanLimit. This patch change it into a command line option
instead of a hardcoded value.

Patched by Xuetian Weng. 

Test Plan: test/Analysis/MemoryDependenceAnalysis/memdep-block-scan-limit.ll

Reviewers: jingyue, reames

Subscribers: reames, llvm-commits

Differential Revision: http://reviews.llvm.org/D11366

llvm-svn: 242842

Check whether BaseCst is valid before extracting a GlobalValue.
This fixes PR24163.

Patch by David Majnemer.

llvm-svn: 242840

llvm-svn: 242839

This makes one substantive change and a few stylistic changes to the
VSX swap optimization pass.

The substantive change is to permit LXSDX and LXSSPX instructions to
participate in swap optimization computations.  The previous change to
insert a swap following a SUBREG_TO_REG widening operation makes this
almost trivial.

I experimented with also permitting STXSDX and STXSSPX instructions.
This can be done using similar techniques:  we could insert a swap
prior to a narrowing COPY operation, and then permit these stores to
participate.  I prototyped this, but discovered that the pattern of a
narrowing COPY followed by an STXSDX does not occur in any of our
test-suite code.  So instead, I added commentary indicating that this
could be done.

Other TLC:
 - I changed SH_COPYSCALAR to SH_COPYWIDEN to more clearly indicate
 the direction of the copy.
 - I factored the insertion of swap instructions into a separate
 function.

Finally, I added a new test case to check that the scalar-to-vector
loads are working properly with swap optimization.

llvm-svn: 242838

This commit refactors the function 'maybeLexGlobalValue' so that now it reuses
the function 'lexName' when lexing a named global value token.

llvm-svn: 242837

llvm-svn: 242834

Not every program needs this information.

In particular, it is necessary and sufficient for a static linker to scan the
section table.

llvm-svn: 242833

llvm-svn: 242830

We were already passing 3 values it can get from ELFDumper.

llvm-svn: 242829

llvm-svn: 242828

Use a named lambda for readability, common some code, remove a stale comments, and use llvm style variable names.

llvm-svn: 242827

To be used in clang in a follow-up commit.

llvm-svn: 242823

llvm-svn: 242821

Every user now keeps track of the correct string table to use.

llvm-svn: 242818

llvm-svn: 242812

This is setup for future work planned for the AArch64 Load/Store Opt pass.

llvm-svn: 242810

The LooksLikeCodeInBug11395() codepath was returning without clearing
the ProcessedAllocas cache.

llvm-svn: 242809

llvm-svn: 242808

We insert a bitcast which obfuscates the getCalledFunction for the utility
function which looks up attributes from the called function. Loosing ABI
changing parameter attributes is a bad thing.

rdar://21516488

llvm-svn: 242807

Reviewers: Duncan P. N. Exon Smith
llvm-svn: 242806

A bit more code cleanup: delete some a trivial true assertion and supporting code, remove a redundant cast, and use count in assertions where feasible.

llvm-svn: 242805

llvm-svn: 242804

This commit extracts the code that prints out a name of an LLVM value without a
prefix from a function 'PrintLLVMName' into a publicly accessible function named
'printLLVMNameWithoutPrefix'.

This change would be useful for MIR serialization, as it would allow the MIR
printer to reuse this function to print out the names of the external symbol
machine operands.

Reviewers: Duncan P. N. Exon Smith
llvm-svn: 242803

llvm-svn: 242802

llvm-svn: 242801

llvm-svn: 242798