287 Commits

Author SHA1 Message Date
James Y Knight
3bab951f0f [opaque pointer types] Pass value type to GetElementPtr creation.
This cleans up all GetElementPtr creation in LLVM to explicitly pass a
value type rather than deriving it from the pointer's element-type.

Differential Revision: https://reviews.llvm.org/D57173

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@352913 91177308-0d34-0410-b5e6-96231b3b80d8
2019-02-01 20:44:47 +00:00
Chandler Carruth
6b547686c5 Update the file headers across all of the LLVM projects in the monorepo
to reflect the new license.

We understand that people may be surprised that we're moving the header
entirely to discuss the new license. We checked this carefully with the
Foundation's lawyer and we believe this is the correct approach.

Essentially, all code in the project is now made available by the LLVM
project under our new license, so you will see that the license headers
include that license only. Some of our contributors have contributed
code under our old license, and accordingly, we have retained a copy of
our old license notice in the top-level files in each project and
repository.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@351636 91177308-0d34-0410-b5e6-96231b3b80d8
2019-01-19 08:50:56 +00:00
Chandler Carruth
81aa712273 [CallSite removal] Migrate all Alias Analysis APIs to use the newly
minted `CallBase` class instead of the `CallSite` wrapper.

This moves the largest interwoven collection of APIs that traffic in
`CallSite`s. While a handful of these could have been migrated with
a minorly more shallow migration by converting from a `CallSite` to
a `CallBase`, it hardly seemed worth it. Most of the APIs needed to
migrate together because of the complex interplay of AA APIs and the
fact that converting from a `CallBase` to a `CallSite` isn't free in its
current implementation.

Out of tree users of these APIs can fairly reliably migrate with some
combination of `.getInstruction()` on the `CallSite` instance and
casting the resulting pointer. The most generic form will look like `CS`
-> `cast_or_null<CallBase>(CS.getInstruction())` but in most cases there
is a more elegant migration. Hopefully, this migrates enough APIs for
users to fully move from `CallSite` to the base class. All of the
in-tree users were easily migrated in that fashion.

Thanks for the review from Saleem!

Differential Revision: https://reviews.llvm.org/D55641

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@350503 91177308-0d34-0410-b5e6-96231b3b80d8
2019-01-07 05:42:51 +00:00
Chandler Carruth
2aaf7228e0 [TI removal] Make variables declared as TerminatorInst and initialized
by `getTerminator()` calls instead be declared as `Instruction`.

This is the biggest remaining chunk of the usage of `getTerminator()`
that insists on the narrow type and so is an easy batch of updates.
Several files saw more extensive updates where this would cascade to
requiring API updates within the file to use `Instruction` instead of
`TerminatorInst`. All of these were trivial in nature (pervasively using
`Instruction` instead just worked).

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@344502 91177308-0d34-0410-b5e6-96231b3b80d8
2018-10-15 10:04:59 +00:00
George Burgess IV
91f4bc63a8 [Analysis] Make LocationSizes carry an 'imprecise' bit
There are places where we need to merge multiple LocationSizes of
different sizes into one, and get a sensible result.

There are other places where we want to optimize aggressively based on
the value of a LocationSizes (e.g. how can a store of four bytes be to
an area of storage that's only two bytes large?)

This patch makes LocationSize hold an 'imprecise' bit to note whether
the LocationSize can be treated as an upper-bound and lower-bound for
the size of a location, or just an upper-bound.

This concludes the series of patches leading up to this. The most recent
of which is r344108.

Fixes PR36228.

Differential Revision: https://reviews.llvm.org/D44748


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@344114 91177308-0d34-0410-b5e6-96231b3b80d8
2018-10-10 06:39:40 +00:00
George Burgess IV
def2c06ca2 Make LocationSize a proper Optional type; NFC
This is the second in a series of changes intended to make
https://reviews.llvm.org/D44748 more easily reviewable. Please see that
patch for more context. The first change being r344012.

Since I was requested to do all of this with post-commit review, this is
about as small as I can make this patch.

This patch makes LocationSize into an actual type that wraps a uint64_t;
users are required to call getValue() in order to get the size now. If
the LocationSize has an Unknown size (e.g. if LocSize ==
MemoryLocation::UnknownSize), getValue() will assert.

This also adds DenseMap specializations for LocationInfo, which required
taking two more values from the set of values LocationInfo can
represent. Hence, heavy users of multi-exabyte arrays or structs may
observe slightly lower-quality code as a result of this change.

The intent is for getValue()s to be very close to a corresponding
hasValue() (which is often spelled `!= MemoryLocation::UnknownSize`).
Sadly, small diff context appears to crop that out sometimes, and the
last change in DSE does require a bit of nonlocal reasoning about
control-flow. :/

This also removes an assert, since it's now redundant with the assert in
getValue().


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@344013 91177308-0d34-0410-b5e6-96231b3b80d8
2018-10-09 03:18:56 +00:00
George Burgess IV
5454da3a19 Use locals instead of struct fields; NFC
This is one of a series of changes intended to make
https://reviews.llvm.org/D44748 more easily reviewable. Please see that
patch for more context.

Since I was requested to do all of this with post-commit review, this is
about as small as I can make it (beyond committing changes to these few
files separately, but they're incredibly similar in spirit, so...)

On its own, this change doesn't make a great deal of sense. I plan on
having a follow-up Real Soon Now(TM) to make the bits here make more
sense. :)

In particular, the next change in this series is meant to make
LocationSize an actual type, which you have to call .getValue() on in
order to get at the uint64_t inside. Hence, this change refactors code
so that:
- we only need to call the soon-to-come getValue() once in most cases,
  and
- said call to getValue() happens very closely to a piece of code that
  checks if the LocationSize has a value (e.g. if it's != UnknownSize).


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@344012 91177308-0d34-0410-b5e6-96231b3b80d8
2018-10-09 02:14:33 +00:00
Jun Lim
f3a3ccda02 Test commit
I just removed a blank space.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@340069 91177308-0d34-0410-b5e6-96231b3b80d8
2018-08-17 18:40:41 +00:00
Fangrui Song
af7b1832a0 Remove trailing space
sed -Ei 's/[[:space:]]+$//' include/**/*.{def,h,td} lib/**/*.{cpp,h}

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@338293 91177308-0d34-0410-b5e6-96231b3b80d8
2018-07-30 19:41:25 +00:00
Manoj Gupta
c6da6867a1 llvm: Add support for "-fno-delete-null-pointer-checks"
Summary:
Support for this option is needed for building Linux kernel.
This is a very frequently requested feature by kernel developers.

More details : https://lkml.org/lkml/2018/4/4/601

GCC option description for -fdelete-null-pointer-checks:
This Assume that programs cannot safely dereference null pointers,
and that no code or data element resides at address zero.

-fno-delete-null-pointer-checks is the inverse of this implying that
null pointer dereferencing is not undefined.

This feature is implemented in LLVM IR in this CL as the function attribute
"null-pointer-is-valid"="true" in IR (Under review at D47894).
The CL updates several passes that assumed null pointer dereferencing is
undefined to not optimize when the "null-pointer-is-valid"="true"
attribute is present.

Reviewers: t.p.northover, efriedma, jyknight, chandlerc, rnk, srhines, void, george.burgess.iv

Reviewed By: efriedma, george.burgess.iv

Subscribers: eraman, haicheng, george.burgess.iv, drinkcat, theraven, reames, sanjoy, xbolva00, llvm-commits

Differential Revision: https://reviews.llvm.org/D47895

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@336613 91177308-0d34-0410-b5e6-96231b3b80d8
2018-07-09 22:27:23 +00:00
Hiroshi Inoue
26570985ef [NFC] fix trivial typos in comments
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@334687 91177308-0d34-0410-b5e6-96231b3b80d8
2018-06-14 05:41:49 +00:00
David Blaikie
8325fb20d4 Move Analysis/Utils/Local.h back to Transforms
Review feedback from r328165. Split out just the one function from the
file that's used by Analysis. (As chandlerc pointed out, the original
change only moved the header and not the implementation anyway - which
was fine for the one function that was used (since it's a
template/inlined in the header) but not in general)

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@333954 91177308-0d34-0410-b5e6-96231b3b80d8
2018-06-04 21:23:21 +00:00
Nicola Zaghen
0818e789cb Rename DEBUG macro to LLVM_DEBUG.
The DEBUG() macro is very generic so it might clash with other projects.
The renaming was done as follows:
- git grep -l 'DEBUG' | xargs sed -i 's/\bDEBUG\s\?(/LLVM_DEBUG(/g'
- git diff -U0 master | ../clang/tools/clang-format/clang-format-diff.py -i -p1 -style LLVM
- Manual change to APInt
- Manually chage DOCS as regex doesn't match it.

In the transition period the DEBUG() macro is still present and aliased
to the LLVM_DEBUG() one.

Differential Revision: https://reviews.llvm.org/D43624



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@332240 91177308-0d34-0410-b5e6-96231b3b80d8
2018-05-14 12:53:11 +00:00
Daniel Neilson
88b5ce0eea [DSE] Teach the pass about partial overwrite of atomic memory intrinsics
Summary:
This change teaches DSE that the atomic memory intrinsics can be overwriten
partially in the same way as the non-atomic forms. Specifically, that the
atomic memcpy & memset can be shortened at the end and that the atomic memset
can be shortened at the beginning, if they partially overwritten
by later stores.

Reviewers: mkazantsev, skatkov, apilipenko, efriedma, rsmith, spatel, filcab, sanjoy

Reviewed By: efriedma

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D45584

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@331991 91177308-0d34-0410-b5e6-96231b3b80d8
2018-05-10 15:12:49 +00:00
Piotr Padlewski
4d0342f0d9 perform DSE through launder.invariant.group
Summary:
Alias Analysis knows that llvm.launder.invariant.group
returns pointer that mustalias argument, but this information
wasn't used, therefor we didn't DSE through launder.invariant.group

Reviewers: chandlerc, dberlin, bogner, hfinkel, efriedma

Reviewed By: dberlin

Subscribers: amharc, llvm-commits, nlewycky, rsmith

Differential Revision: https://reviews.llvm.org/D31581

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@331449 91177308-0d34-0410-b5e6-96231b3b80d8
2018-05-03 11:03:53 +00:00
Daniel Neilson
6c92ba3e0b [DSE] Teach the pass that atomic memory intrinsics are stores.
Summary:
This change teaches DSE that the atomic memory intrinsics are stores
that can be eliminated, and can allow other stores to be eliminated.
This change specifically does not teach DSE that these intrinsics
can be partially eliminated (i.e. length reduced, and dest/src changed);
that will be handled in another change.

Reviewers: mkazantsev, skatkov, apilipenko, efriedma, rsmith

Reviewed By: efriedma

Subscribers: dmgreen, llvm-commits

Differential Revision: https://reviews.llvm.org/D45535

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@330629 91177308-0d34-0410-b5e6-96231b3b80d8
2018-04-23 19:06:49 +00:00
David Blaikie
283527b390 Fix a couple of layering violations in Transforms
Remove #include of Transforms/Scalar.h from Transform/Utils to fix layering.

Transforms depends on Transforms/Utils, not the other way around. So
remove the header and the "createStripGCRelocatesPass" function
declaration (& definition) that is unused and motivated this dependency.

Move Transforms/Utils/Local.h into Analysis because it's used by
Analysis/MemoryBuiltins.cpp.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@328165 91177308-0d34-0410-b5e6-96231b3b80d8
2018-03-21 22:34:23 +00:00
Sanjoy Das
9302e9a500 [DSE] Don't DSE stores that subsequent memmove calls read from
Summary:
We used to remove the first memmove in cases like this:

  memmove(p, p+2, 8);
  memmove(p, p+2, 8);

which is incorrect.  Fix this by changing isPossibleSelfRead to what was most
likely the intended behavior.

Historical note: the buggy code was added in https://reviews.llvm.org/rL120974
to address PR8728.

Reviewers: rsmith

Subscribers: mcrosier, llvm-commits, jlebar

Differential Revision: https://reviews.llvm.org/D43425

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@325641 91177308-0d34-0410-b5e6-96231b3b80d8
2018-02-20 23:19:34 +00:00
Vedant Kumar
c9c691411d [DeadStoreElimination] Salvage debug info from dead insts
According to `llvm-dwarfdump --statistics` this salvages 43 additional
unique source variables in a stage2 build of clang. It increases the
size of the .debug_loc section by 0.002% (or 2864 bytes).

Differential Revision: https://reviews.llvm.org/D43220

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@325035 91177308-0d34-0410-b5e6-96231b3b80d8
2018-02-13 18:15:26 +00:00
Daniel Neilson
0f6540180d [DSE] Upgrade uses of MemoryIntrinic::getAlignment() to new API. (NFC)
Summary:
This change is part of step five in the series of changes to remove alignment argument from
memcpy/memmove/memset in favour of alignment attributes. In particular, this changes the
DeadStoreElimination pass to cease using the old getAlignment() API of MemoryIntrinsic
in favour of getting dest specific alignments through the new API.

Steps:
Step 1) Remove alignment parameter and create alignment parameter attributes for
memcpy/memmove/memset. ( rL322965, rC322964, rL322963 )
Step 2) Expand the IRBuilder API to allow creation of memcpy/memmove with differing
source and dest alignments. ( rL323597 )
Step 3) Update Clang to use the new IRBuilder API. ( rC323617 )
Step 4) Update Polly to use the new IRBuilder API. ( rL323618 )
Step 5) Update LLVM passes that create memcpy/memmove calls to use the new IRBuilder API,
and those that use use MemIntrinsicInst::[get|set]Alignment() to use [get|set]DestAlignment()
and [get|set]SourceAlignment() instead. ( rL323886, rL323891, rL324148, rL324273, rL324278,
rL324384, rL324395 )
Step 6) Remove the single-alignment IRBuilder API for memcpy/memmove, and the
MemIntrinsicInst::[get|set]Alignment() methods.

Reference
   http://lists.llvm.org/pipermail/llvm-dev/2015-August/089384.html
   http://lists.llvm.org/pipermail/llvm-commits/Week-of-Mon-20151109/312083.html

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@324402 91177308-0d34-0410-b5e6-96231b3b80d8
2018-02-06 21:18:33 +00:00
Sanjay Patel
771594b9ab [DSE] make sure memory is not modified before partial store merging (PR36129)
We missed a critical check in D30703. We must make sure that no intermediate 
store is sitting between the stores that we want to merge.

This should fix:
https://bugs.llvm.org/show_bug.cgi?id=36129

Differential Revision: https://reviews.llvm.org/D42663


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@323759 91177308-0d34-0410-b5e6-96231b3b80d8
2018-01-30 13:53:59 +00:00
Philip Reames
840901cb39 [DSE] Factor out common code [NFC]
We already had the pointer being stored to in the MemLoc, reuse that code.  In merging cases, it turned out the interface of the getLocForWrite had become inconsitent with other related utilities.  Fix that by making sure the input passes hasAnalyzableWrite as well.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@323056 91177308-0d34-0410-b5e6-96231b3b80d8
2018-01-21 02:10:54 +00:00
Philip Reames
7f165c8ada [DSE] Minor rename for clarity sake [NFC]
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@323055 91177308-0d34-0410-b5e6-96231b3b80d8
2018-01-21 01:44:33 +00:00
Alina Sbirlea
a2d30e9740 Modify ModRefInfo values using static inline method abstractions [NFC].
Summary:
The aim is to make ModRefInfo checks and changes more intuitive
and less error prone using inline methods that abstract the bit operations.

Ideally ModRefInfo would become an enum class, but that change will require
a wider set of changes into FunctionModRefBehavior.

Reviewers: sanjoy, george.burgess.iv, dberlin, hfinkel

Subscribers: nlopes, llvm-commits

Differential Revision: https://reviews.llvm.org/D40749

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@319821 91177308-0d34-0410-b5e6-96231b3b80d8
2017-12-05 20:12:23 +00:00
Eugene Zelenko
f85a6f9ed6 [Transforms] Fix some Clang-tidy modernize and Include What You Use warnings; other minor fixes (NFC).
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@315760 91177308-0d34-0410-b5e6-96231b3b80d8
2017-10-13 21:17:07 +00:00
Sanjay Patel
5f82c06110 [DSE] Merge stores when the later store only writes to memory locations the early store also wrote to (2nd try)
This is a 2nd attempt at:
https://reviews.llvm.org/rL310055
...which was reverted at rL310123 because of PR34074:
https://bugs.llvm.org/show_bug.cgi?id=34074

In this version, we break out of the inner loop after we successfully merge and kill a pair of stores. In the
earlier rev, we were continuing instead, which meant we could process the invalid info from a now dead store.

Original commit message (authored by Filipe Cabecinhas):

This fixes PR31777.

If both stores' values are ConstantInt, we merge the two stores
(shifting the smaller store appropriately) and replace the earlier (and
larger) store with an updated constant.

In the future we should also support vectors of integers. And maybe
float/double if we can.  

Differential Revision: https://reviews.llvm.org/D30703


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@314206 91177308-0d34-0410-b5e6-96231b3b80d8
2017-09-26 13:54:28 +00:00
Nico Weber
4aabf12607 Revert r310055, it caused PR34074.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@310123 91177308-0d34-0410-b5e6-96231b3b80d8
2017-08-04 20:40:38 +00:00
Filipe Cabecinhas
f27bcb0a8e [DSE] Merge stores when the later store only writes to memory locations the early store also wrote to.
Summary:
This fixes PR31777.

If both stores' values are ConstantInt, we merge the two stores
(shifting the smaller store appropriately) and replace the earlier (and
larger) store with an updated constant.

In the future we should also support vectors of integers. And maybe
float/double if we can.

Reviewers: hfinkel, junbuml, jfb, RKSimon, bkramer

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D30703

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@310055 91177308-0d34-0410-b5e6-96231b3b80d8
2017-08-04 12:28:36 +00:00
Filipe Cabecinhas
65afd8323d Cleanup in preparation for D30703. NFCI
Make the enumerators follow the coding convention and start with OW_...

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@298996 91177308-0d34-0410-b5e6-96231b3b80d8
2017-03-29 14:42:27 +00:00
Igor Laevsky
f789f6f9d7 [DeadStoreElimination] Check function modref behavior before considering memory clobbered
Differential Revision: https://reviews.llvm.org/D29996



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@296625 91177308-0d34-0410-b5e6-96231b3b80d8
2017-03-01 14:38:29 +00:00
David L. Jones
32028c8f08 [Analysis] Add LibFunc_ prefix to enums in TargetLibraryInfo. (NFC)
Summary:
The LibFunc::Func enum holds enumerators named for libc functions.
Unfortunately, there are real situations, including libc implementations, where
function names are actually macros (musl uses "#define fopen64 fopen", for
example; any other transitively visible macro would have similar effects).

Strictly speaking, a conforming C++ Standard Library should provide any such
macros as functions instead (via <cstdio>). However, there are some "library"
functions which are not part of the standard, and thus not subject to this
rule (fopen64, for example). So, in order to be both portable and consistent,
the enum should not use the bare function names.

The old enum naming used a namespace LibFunc and an enum Func, with bare
enumerators. This patch changes LibFunc to be an enum with enumerators prefixed
with "LibFFunc_". (Unfortunately, a scoped enum is not sufficient to override
macros.)

There are additional changes required in clang.

Reviewers: rsmith

Subscribers: mehdi_amini, mzolotukhin, nemanjai, llvm-commits

Differential Revision: https://reviews.llvm.org/D28476

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@292848 91177308-0d34-0410-b5e6-96231b3b80d8
2017-01-23 23:16:46 +00:00
Chandler Carruth
10dd00ced5 [PM] Introduce an analysis set used to preserve all analyses over
a function's CFG when that CFG is unchanged.

This allows transformation passes to simply claim they preserve the CFG
and analysis passes to check for the CFG being preserved to remove the
fanout of all analyses being listed in all passes.

I've gone through and removed or cleaned up as many of the comments
reminding us to do this as I could.

Differential Revision: https://reviews.llvm.org/D28627

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@292054 91177308-0d34-0410-b5e6-96231b3b80d8
2017-01-15 06:32:49 +00:00
Bob Haarman
6deac82729 limit the number of instructions per block examined by dead store elimination
Summary: Dead store elimination gets very expensive when large numbers of instructions need to be analyzed. This patch limits the number of instructions analyzed per store to the value of the memdep-block-scan-limit parameter (which defaults to 100). This resulted in no observed difference in performance of the generated code, and no change in the statistics for the dead store elimination pass, but improved compilation time on some files by more than an order of magnitude.

Reviewers: dexonsmith, bruno, george.burgess.iv, dberlin, reames, davidxl

Subscribers: davide, chandlerc, dberlin, davidxl, eraman, tejohnson, mbodart, llvm-commits

Differential Revision: https://reviews.llvm.org/D15537

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@279833 91177308-0d34-0410-b5e6-96231b3b80d8
2016-08-26 16:34:27 +00:00
Bob Haarman
2adbfa1846 test commit
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@279830 91177308-0d34-0410-b5e6-96231b3b80d8
2016-08-26 16:00:04 +00:00
Eli Friedman
35ff6f0857 [DSE] Don't remove stores made live by a call which unwinds.
Issue exposed by noalias or more aggressive alias analysis.

Fixes http://llvm.org/PR25422.

Differential revision: https://reviews.llvm.org/D21007



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@278451 91177308-0d34-0410-b5e6-96231b3b80d8
2016-08-12 01:09:53 +00:00
Jun Bum Lim
3655e657b3 [DSE] Fix bug in updating MadeChange flag
Summary: The MadeChange flag should be ORed to keep the previous result.

Reviewers: mcrosier

Subscribers: mcrosier, llvm-commits

Differential Revision: https://reviews.llvm.org/D22873

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@276894 91177308-0d34-0410-b5e6-96231b3b80d8
2016-07-27 17:25:20 +00:00
Jun Bum Lim
0618303382 Recommit - [DSE]Enhance shorthening MemIntrinsic based on OverlapIntervals
Recommiting r275571 after fixing crash reported in PR28270.
Now we erase elements of IOL in deleteDeadInstruction().

Original Summary:
This change use the overlap interval map built from partial overwrite tracking to perform shortening MemIntrinsics.
Add test cases which was missing opportunities before.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@276452 91177308-0d34-0410-b5e6-96231b3b80d8
2016-07-22 18:27:24 +00:00
Chad Rosier
fbab381e3c [DSE] Add additional debug output. NFC.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@276005 91177308-0d34-0410-b5e6-96231b3b80d8
2016-07-19 18:11:11 +00:00
Chad Rosier
33f915946e [DSE] Add additional debug output. NFC.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@275991 91177308-0d34-0410-b5e6-96231b3b80d8
2016-07-19 16:50:57 +00:00
Alexander Kornienko
71c0ef585b Revert "r275571 [DSE]Enhance shorthening MemIntrinsic based on OverlapIntervals"
Causes https://llvm.org/bugs/show_bug.cgi?id=28588


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@275801 91177308-0d34-0410-b5e6-96231b3b80d8
2016-07-18 15:51:31 +00:00
Jun Bum Lim
2ca934ea31 [DSE]Enhance shorthening MemIntrinsic based on OverlapIntervals
Summary:
This change use the overlap interval map built from partial overwrite tracking to perform shortening MemIntrinsics.
Add test cases which was missing opportunities before.

Reviewers: hfinkel, eeckstein, mcrosier

Subscribers: mcrosier, llvm-commits

Differential Revision: https://reviews.llvm.org/D21909

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@275571 91177308-0d34-0410-b5e6-96231b3b80d8
2016-07-15 16:14:34 +00:00
Benjamin Kramer
a27e16e477 Give helper classes/functions internal linkage. NFC.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@275014 91177308-0d34-0410-b5e6-96231b3b80d8
2016-07-10 11:28:51 +00:00
Chad Rosier
fbfe050d03 [DSE] Minor refactor based on D21007. NFC.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@274877 91177308-0d34-0410-b5e6-96231b3b80d8
2016-07-08 16:48:40 +00:00
Anna Thomas
6a6fa34ee1 [DSE] Remove dead stores in end blocks containing fence
We can remove dead stores in the presence of fence instructions. Fence
does not change an otherwise thread local store to visible.

reviewers: reames, dexonsmith, jfb
Differential Revision: http://reviews.llvm.org/D22001

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@274795 91177308-0d34-0410-b5e6-96231b3b80d8
2016-07-07 20:51:42 +00:00
Chad Rosier
9b917c506a [DSE] Avoid iterator invalidation bugs.
The dse_with_dbg_value.ll test committed with r273141 is removed because this
we no longer performs any type of back tracking, which is what was causing the
codegen differences with and without debug information.

Differential Revision: http://reviews.llvm.org/D21613

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@274660 91177308-0d34-0410-b5e6-96231b3b80d8
2016-07-06 19:48:52 +00:00
Jun Bum Lim
fe4360eba5 [DSE] Fix bug in partial overwrite tracking
Summary:
Found cases where DSE incorrectly add partially-overwritten intervals.
Please see the test case for details.

Reviewers: mcrosier, eeckstein, hfinkel

Subscribers: mcrosier, llvm-commits

Differential Revision: http://reviews.llvm.org/D21859

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@274237 91177308-0d34-0410-b5e6-96231b3b80d8
2016-06-30 15:32:20 +00:00
Benjamin Kramer
5288df58b7 Apply clang-tidy's modernize-loop-convert to most of lib/Transforms.
Only minor manual fixes. No functionality change intended.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@273808 91177308-0d34-0410-b5e6-96231b3b80d8
2016-06-26 12:28:59 +00:00
Hal Finkel
3ae5db8d60 Allow DeadStoreElimination to track combinations of partial later wrties
DeadStoreElimination can currently remove a small store rendered unnecessary by
a later larger one, but could not remove a larger store rendered unnecessary by
a series of later smaller ones. This adds that capability.

It works by keeping a map, which is used as an effective interval map, for each
store later overwritten only partially, and filling in that interval map as
more such stores are discovered. No additional walking or aliasing queries are
used. In the map forms an interval covering the the entire earlier store, then
it is dead and can be removed. The map is used as an interval map by storing a
mapping between the ending offset and the beginning offset of each interval.

I discovered this problem when investigating a performance issue with code like
this on PowerPC:

  #include <complex>
  using namespace std;

  complex<float> bar(complex<float> C);
  complex<float> foo(complex<float> C) {
    return bar(C)*C;
  }

which produces this:

  define void @_Z4testSt7complexIfE(%"struct.std::complex"* noalias nocapture sret %agg.result, i64 %c.coerce) {
  entry:
    %ref.tmp = alloca i64, align 8
    %tmpcast = bitcast i64* %ref.tmp to %"struct.std::complex"*
    %c.sroa.0.0.extract.shift = lshr i64 %c.coerce, 32
    %c.sroa.0.0.extract.trunc = trunc i64 %c.sroa.0.0.extract.shift to i32
    %0 = bitcast i32 %c.sroa.0.0.extract.trunc to float
    %c.sroa.2.0.extract.trunc = trunc i64 %c.coerce to i32
    %1 = bitcast i32 %c.sroa.2.0.extract.trunc to float
    call void @_Z3barSt7complexIfE(%"struct.std::complex"* nonnull sret %tmpcast, i64 %c.coerce)
    %2 = bitcast %"struct.std::complex"* %agg.result to i64*
    %3 = load i64, i64* %ref.tmp, align 8
    store i64 %3, i64* %2, align 4 ; <--- ***** THIS SHOULD NOT BE HERE ****
    %_M_value.realp.i.i = getelementptr inbounds %"struct.std::complex", %"struct.std::complex"* %agg.result, i64 0, i32 0, i32 0
    %4 = lshr i64 %3, 32
    %5 = trunc i64 %4 to i32
    %6 = bitcast i32 %5 to float
    %_M_value.imagp.i.i = getelementptr inbounds %"struct.std::complex", %"struct.std::complex"* %agg.result, i64 0, i32 0, i32 1
    %7 = trunc i64 %3 to i32
    %8 = bitcast i32 %7 to float
    %mul_ad.i.i = fmul fast float %6, %1
    %mul_bc.i.i = fmul fast float %8, %0
    %mul_i.i.i = fadd fast float %mul_ad.i.i, %mul_bc.i.i
    %mul_ac.i.i = fmul fast float %6, %0
    %mul_bd.i.i = fmul fast float %8, %1
    %mul_r.i.i = fsub fast float %mul_ac.i.i, %mul_bd.i.i
    store float %mul_r.i.i, float* %_M_value.realp.i.i, align 4
    store float %mul_i.i.i, float* %_M_value.imagp.i.i, align 4
    ret void
  }

the problem here is not just that the i64 store is unnecessary, but also that
it blocks further backend optimizations of the other uses of that i64 value in
the backend.

In the future, we might want to add a special case for handling smaller
accesses (e.g. using a bit vector) if the map mechanism turns out to be
noticeably inefficient. A sorted vector is also a possible replacement for the
map for small numbers of tracked intervals.

Differential Revision: http://reviews.llvm.org/D18586

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@273559 91177308-0d34-0410-b5e6-96231b3b80d8
2016-06-23 13:46:39 +00:00
Patrik Hagglund
76e55eedd6 Fix for PR27940
After a store has been eliminated, when making sure that the
instruction iterator points to a valid instruction, dbg intrinsics are
now ignored as a new instruction.

Patch by Henric Karlsson.

Reviewed by Daniel Berlin.

Differential Revision: http://reviews.llvm.org/D21076

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@273141 91177308-0d34-0410-b5e6-96231b3b80d8
2016-06-20 09:10:10 +00:00
Chad Rosier
8e662dc4d5 [DSE] Minor style cleanup. NFC.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@272922 91177308-0d34-0410-b5e6-96231b3b80d8
2016-06-16 17:06:04 +00:00