routine.
We were getting this wrong in small ways and generally being very
inconsistent about it across loop passes. Instead, let's have a common
place where we do this. One minor downside is that this will require
some analyses like SCEV in more places than they are strictly needed.
However, this seems benign as these analyses are complete no-ops, and
without this consistency we can in many cases end up with the legacy
pass manager scheduling deciding to split up a loop pass pipeline in
order to run the function analysis half-way through. It is very, very
annoying to fix these without just being very pedantic across the board.
The only loop passes I've not updated here are ones that use
AU.setPreservesAll() such as IVUsers (an analysis) and the pass printer.
They seemed less relevant.
With this patch, almost all of the problems in PR24804 around loop pass
pipelines are fixed. The one remaining issue is that we run simplify-cfg
and instcombine in the middle of the loop pass pipeline. We've recently
added some loop variants of these passes that would seem substantially
cleaner to use, but this at least gets us much closer to the previous
state. Notably, the seven loop pass managers is down to three.
I've not updated the loop passes using LoopAccessAnalysis because that
analysis hasn't been fully wired into LoopSimplify/LCSSA, and it isn't
clear that those transforms want to support those forms anyways. They
all run late anyways, so this is harmless. Similarly, LSR is left alone
because it already carefully manages its forms and doesn't need to get
fused into a single loop pass manager with a bunch of other loop passes.
LoopReroll didn't use loop simplified form previously, and I've updated
the test case to match the trivially different output.
Finally, I've also factored all the pass initialization for the passes
that use this technique as well, so that should be done regularly and
reliably.
Thanks to James for the help reviewing and thinking about this stuff,
and Ben for help thinking about it as well!
Differential Revision: http://reviews.llvm.org/D17435
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@261316 91177308-0d34-0410-b5e6-96231b3b80d8
more places to prevent gratuitous re-"runs" of these passes.
The passes themselves don't do any work when run, but we keep spending
time scheduling and running these needlessly when we really don't need
to do so.
This is the first patch towards fixing the really horrible loop pass
pipeline fragmentation pointed out by Sanjoy in PR24804.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@261302 91177308-0d34-0410-b5e6-96231b3b80d8
Commit r259357 was reverted because it caused PR26629. We were assuming all
roots of a vectorizable tree could be truncated to the same width, which is not
the case in general. This commit reapplies the patch along with a fix and a new
test case to ensure we don't regress because of this issue again. This should
fix PR26629.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@261212 91177308-0d34-0410-b5e6-96231b3b80d8
convert one test to use this.
This is a particularly significant milestone because it required
a working per-function AA framework which can be queried over each
function from within a CGSCC transform pass (and additionally a module
analysis to be accessible). This is essentially *the* point of the
entire pass manager rewrite. A CGSCC transform is able to query for
multiple different function's analysis results. It works. The whole
thing appears to actually work and accomplish the original goal. While
we were able to hack function attrs and basic-aa to "work" in the old
pass manager, this port doesn't use any of that, it directly leverages
the new fundamental functionality.
For this to work, the CGSCC framework also has to support SCC-based
behavior analysis, etc. The only part of the CGSCC pass infrastructure
not sorted out at this point are the updates in the face of inlining and
running function passes that mutate the call graph.
The changes are pretty boring and boiler-plate. Most of the work was
factored into more focused preperatory patches. But this is what wires
it all together.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@261203 91177308-0d34-0410-b5e6-96231b3b80d8
This function is used to check whether a dbg.value intrinsic has already
been inserted, but without comparing the DIExpression, it would erroneously
fire on split aggregates and only the first scalar would survive.
Found via http://reviews.llvm.org/D16867.
<rdar://problem/24456528>
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@261145 91177308-0d34-0410-b5e6-96231b3b80d8
Summary: Store and loads unpacked by instcombine do not always have the right alignement. This explicitely compute the alignement and set it.
Reviewers: dblaikie, majnemer, reames, hfinkel, joker.eph
Subscribers: llvm-commits
Differential Revision: http://reviews.llvm.org/D17326
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@261139 91177308-0d34-0410-b5e6-96231b3b80d8
When support for objc_unsafeClaimAutoreleasedReturnValue has been added to the
ARC optimizer in r258970, one case was missed which would lead the optimizer
to execute an llvm_unreachable. In this case, just handle ClaimRV in the same
way we handle RetainRV.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@261134 91177308-0d34-0410-b5e6-96231b3b80d8
Summary:
On the contrary to Full LTO, ThinLTO can afford to shift compile time
from the frontend to the linker: both phases are parallel (even if
it is not totally "free": projects like clang are reusing product
from the "compile phase" for multiple link, think about
libLLVMSupport reused for opt, llc, etc.).
This pipeline is based on the proposal in D13443 for full LTO. We
didn't move forward on this proposal because the LTO link was far too
long after that. We believe that we can afford it with ThinLTO.
The ThinLTO pipeline integrates in the regular O2/O3 flow:
- The compile phase perform the inliner with a somehow lighter
function simplification. (TODO: tune the inliner thresholds here)
This is intendend to simplify the IR and get rid of obvious things
like linkonce_odr that will be inlined.
- The link phase will run the pipeline from the start, extended with
some specific passes that leverage the augmented knowledge we have
during LTO. Especially after the inliner is done, a sequence of
globalDCE/globalOpt is performed, followed by another run of the
"function simplification" passes. It is not clear if this part
of the pipeline will stay as is, as the split model of ThinLTO
does not allow the same benefit as FullLTO without added tricks.
The measurements on the public test suite as well as on our internal
suite show an overall net improvement. The binary size for the clang
executable is reduced by 5%. We're still tuning it with the bringup
of ThinLTO and it will evolve, but this should provide a good starting
point.
Reviewers: tejohnson
Differential Revision: http://reviews.llvm.org/D17115
From: Mehdi Amini <mehdi.amini@apple.com>
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@261029 91177308-0d34-0410-b5e6-96231b3b80d8
It is intended to contains the passes run over a function after the
inliner is done with a function and before it moves to its callers.
From: Mehdi Amini <mehdi.amini@apple.com>
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@261028 91177308-0d34-0410-b5e6-96231b3b80d8
Summary:
While shrinking types according to the required bits, we can
encounter insert/extract element instructions. This will cause us to
reach an llvm_unreachable statement.
This change adds support for truncating insert/extract element
operations, and adds a regression test.
Reviewers: jmolloy
Subscribers: mzolotukhin, llvm-commits
Differential Revision: http://reviews.llvm.org/D17078
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@260893 91177308-0d34-0410-b5e6-96231b3b80d8
LICM starts with an *empty* AST, and then merges in each sub-loop. While the
add code is appropriate for sub-loop 2 and up, it's utterly unnecessary for
sub-loop 1. If the AST starts off empty, we can just clone/move the contents
of the subloop into the containing AST.
Reviewed-by: Philip Reames <listmail@philipreames.com>
Differential Revision: http://reviews.llvm.org/D16753
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@260892 91177308-0d34-0410-b5e6-96231b3b80d8
than the SCC object, and have it scan the instruction stream directly
rather than relying on call records.
This makes the behavior of this routine consistent between libc routines
and LLVM intrinsics for libc routines. We can go and start teaching it
about those being norecurse, but we should behave the same for the
intrinsic and the libc routine rather than differently. I chatted with
James Molloy and the inconsistency doesn't seem intentional and likely
is due to intrinsic calls not being modelled in the call graph analyses.
This also fixes a bug where we would deduce norecurse on optnone
functions, when generally we try to handle optnone functions as-if they
were replaceable and thus unanalyzable.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@260813 91177308-0d34-0410-b5e6-96231b3b80d8
Summary:
Export the CloneDebugInfoMetadata utility, which clones all debug info
associated with a function into the first module. Also use this function
in CloneModule on each function we clone (the CloneFunction entrypoint
already does this).
Without this, cloning a module will lead to DI quality regressions,
especially since r252219 reversed the Function <-> DISubprogram edge
(before we could get lucky and have this edge preserved if the
DISubprogram itself was, e.g. due to location metadata).
This was verified to fix missing debug information in julia and
a unittest to verify the new behavior is included.
Patch by Yichao Yu! Thanks!
Reviewers: loladiro, pcc
Differential Revision: http://reviews.llvm.org/D17165
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@260791 91177308-0d34-0410-b5e6-96231b3b80d8
Summary:
Performing this optimization duplicates the call to the convergent
function and adds new control-flow dependencies, which is a no-no.
Reviewers: jingyue
Subscribers: broune, hfinkel, tra, resistor, joker.eph, arsenm, llvm-commits, mzolotukhin
Differential Revision: http://reviews.llvm.org/D17128
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@260730 91177308-0d34-0410-b5e6-96231b3b80d8
Summary:
Calls to convergent functions can be duplicated, but only if the
duplicates are not control-flow dependent on any additional values.
Loop rotation doesn't meet the bar.
Reviewers: jingyue
Subscribers: mzolotukhin, llvm-commits, arsenm, joker.eph, resistor, tra, hfinkel, broune
Differential Revision: http://reviews.llvm.org/D17127
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@260729 91177308-0d34-0410-b5e6-96231b3b80d8
The attached patch removes all of the block local code for performing X-load forwarding by reusing the code used in the non-local case.
The motivation here is to remove duplication and in the process increase our test coverage of some fairly tricky code. I have some upcoming changes I'll be proposing in this area and wanted to have the code cleaned up a bit first.
Note: The review for this mostly happened in email which didn't make it to phabricator on the 258882 commit thread.
Differential Revision: http://reviews.llvm.org/D16608
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@260711 91177308-0d34-0410-b5e6-96231b3b80d8
In short, before r252926 we were comparing an unsigned (StoreSize) against an a
APInt (Stride), which is fine and well. After we were zero extending the Stride
and then converting to an unsigned, which is not the same thing. Obviously,
Stides can also be negative. This commit just restores the original behavior.
AFAICT, it's not possible to write a test case to expose the issue because
the code already has checks to make sure the StoreSize can't overflow an
unsigned (which prevents the Stride from overflowing an unsigned as well).
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@260706 91177308-0d34-0410-b5e6-96231b3b80d8
For some cases, InstCombine replaces the sequence of xor/sub instruction
followed by cmp instruction into a single cmp instruction.
However, this replacement may result suboptimal result especially when
the xor/sub has more than one use, as discussed in
bug 26465 (https://llvm.org/bugs/show_bug.cgi?id=26465).
This patch make the replacement happen only when xor/sub has only one
use.
Differential Revision: http://reviews.llvm.org/D16915
Patch by Taewook Oh!
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@260695 91177308-0d34-0410-b5e6-96231b3b80d8
node set rather than walking the SCC directly.
This directly exposes the functions and has already had null entries
filtered out. We also don't need need to handle optnone as it has
already been handled in the caller -- we never try to remove convergent
when there are optnone functions in the SCC.
With this change, the code for removing convergent should work with the
new pass manager and a different SCC analysis.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@260668 91177308-0d34-0410-b5e6-96231b3b80d8
with the test for a non-convergent intrinsic call.
While it is possible to use the call records to search for function
calls, we're going to do an instruction scan anyways to find the
intrinsics, we can handle both cases while scanning instructions. This
will also make the logic more amenable to the new pass manager which
doesn't use the same call graph structure.
My next patch will remove use of CallGraphNode entirely and allow this
code to work with both the old and new pass manager. Fortunately, it
should also get strictly simpler without changing functionality.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@260666 91177308-0d34-0410-b5e6-96231b3b80d8
MSan adds a constructor to each translation unit that calls
__msan_init, and does nothing else. The idea is to run __msan_init
before any instrumented code. This results in multiple constructors
and multiple .init_array entries in the final binary, one per
translation unit. This is absolutely unnecessary; one would be
enough.
This change moves the constructors to a comdat group in order to drop
the extra ones.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@260632 91177308-0d34-0410-b5e6-96231b3b80d8
Original commit message:
[InstCombine] Fold IntToPtr and PtrToInt into preceding loads.
Currently we only fold a BitCast into a Load when the BitCast is its
only user.
Do the same for any no-op cast.
Patch by Philip Pfaffe!
Differential Revision: http://reviews.llvm.org/D9152
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@260612 91177308-0d34-0410-b5e6-96231b3b80d8
This reverts commit r260604.
I didn't intend to push this now.
From: Mehdi Amini <mehdi.amini@apple.com>
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@260606 91177308-0d34-0410-b5e6-96231b3b80d8
Summary:
On the contrary to Full LTO, ThinLTO can afford to shift compile time
from the frontend to the linker: both phases are parallel.
This pipeline is based on the proposal in D13443 for full LTO. We ]
didn't move forward on this proposal because the link was far too long
after that.
This patch refactor the "function simplification" passes that are part
of the inliner loop in a helper function (this part is NFC and can be
commited separately to simplify the diff). The ThinLTO pipeline
integrates in the regular O2/O3 flow:
- The compile phase perform the inliner with a somehow lighter
function simplification. (TODO: tune the inliner thresholds here)
This is intendend to simplify the IR and get rid of obvious things
like linkonce_odr that will be inlined.
- The link phase will run the pipeline from the start, extended with
some specific passes that leverage the augmented knowledge we have
during LTO. Especially after the inliner is done, a sequence of
globalDCE/globalOpt is performed, followed by another run of the
"function simplification" passes.
The measurements on the public test suite as well as on our internal
suite show an overall net improvement. The binary size for the clang
executable is reduced by 5%. We're still tuning it with the bringup
of ThinLTO but this should provide a good starting point.
Reviewers: tejohnson
Subscribers: joker.eph, llvm-commits, dexonsmith
Differential Revision: http://reviews.llvm.org/D17115
From: Mehdi Amini <mehdi.amini@apple.com>
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@260604 91177308-0d34-0410-b5e6-96231b3b80d8
It is intended to contains the passes run over a function after the
inliner is done with a function and before it moves to its callers.
From: Mehdi Amini <mehdi.amini@apple.com>
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@260603 91177308-0d34-0410-b5e6-96231b3b80d8
When optimizing a extractvalue(load), we generate a load from the
aggregate type. This load didn't have alignment set and so would
get the alignment of the type. This breaks when the type is packed
and so the alignment should be lower.
For example, loading { int, int } would give us alignment of 4, but
the original load from this type may have an alignment of 1 if packed.
Reviewed by David Majnemer
Differential revision: http://reviews.llvm.org/D17158
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@260587 91177308-0d34-0410-b5e6-96231b3b80d8
Summary:
When a PHI is used only to be compared with zero, it is possible to replace an
incoming value with any non-zero constant if the incoming value can be proved as
a known nonzero value. For example, in below code, we can replace the incoming value %v with
any non-zero constant based on the fact that the PHI is only used to be compared with zero
and %v is a known non-zero value:
%v = select %cond, 1, 2
%p = phi [%v, BB] ...
%c = icmp eq, %p, 0
Reviewers: mcrosier, jmolloy, sanjoy
Subscribers: hfinkel, mcrosier, majnemer, llvm-commits, haicheng, bmakam, mssimpso, gberry
Differential Revision: http://reviews.llvm.org/D16240
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@260530 91177308-0d34-0410-b5e6-96231b3b80d8
Make sure we split ":" from the end of the global function id (which
is <path>:<function> for local functions) instead of the beginning to
avoid splitting at the wrong place for Windows file paths that contain
a ":".
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@260469 91177308-0d34-0410-b5e6-96231b3b80d8
The current function importer will walk the callgraph, importing
transitively any callee that is below the threshold. This can
lead to import very deep which is costly in compile time and not
necessarily beneficial as most of the inline would happen in
imported function and not necessarilly in user code.
The actual factor has been carefully chosen by flipping a coin ;)
Some tuning need to be done (just at the existing limiting threshold).
Reviewers: tejohnson
Differential Revision: http://reviews.llvm.org/D17082
From: Mehdi Amini <mehdi.amini@apple.com>
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@260466 91177308-0d34-0410-b5e6-96231b3b80d8