Summary:
We only modify CFG in a couple of places, and we can preserve DT there
with a little effort.
Reviewers: davide, vsk
Subscribers: hiraditya, llvm-commits
Differential Revision: https://reviews.llvm.org/D48059
llvm-svn: 334895
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)
llvm-svn: 333954
We were previously using a DT in CVP through SimplifyQuery, but not requiring it in
the new pass manager. Hence it would crash if DT was not already available. This now
gets DT directly and plumbs it through to where it is used (instead of using it
through SQ).
llvm-svn: 332836
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
llvm-svn: 332240
This is based on an example that was recently posted on llvm-dev:
void *propagate_null(void* b, int* g) {
if (!b) {
return 0;
}
(*g)++;
return b;
}
https://godbolt.org/g/xYk3qG
The original code or constant propagation in other passes has obscured the fact
that the phi can be removed completely.
Differential Revision: https://reviews.llvm.org/D45448
llvm-svn: 329755
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.
llvm-svn: 328165
Summary:
If the operands of a udiv/urem can be proved to fit within a smaller
power-of-two-sized type, reduce the width of the udiv/urem.
Backed out for causing performance regressions. Re-landing
because we've determined that these regressions were noise.
Original Differential Revision: https://reviews.llvm.org/D44102
llvm-svn: 328096
This reverts r326908, originally landed as D44102.
Reverted for causing performance regressions on x86. (These regressions
are not yet understood.)
llvm-svn: 327252
Summary:
If the operands of a udiv/urem can be proved to fit within a smaller
power-of-two-sized type, reduce the width of the udiv/urem.
Backed out for failing an assert in clang bootstrap builds. Re-landing
with a fix for handling non-power-of-two inputs (e.g. udiv i24).
Original Differential Revision: https://reviews.llvm.org/D44102
llvm-svn: 326908
Breaks bootstrap builds: clang built with this patch asserts while
building MCDwarf.cpp: Assertion `castIsValid(op, S, Ty) && "Invalid
cast!"' failed.
llvm-svn: 326900
Summary:
If the operands of a udiv/urem can be proved to fit within a smaller
power-of-two-sized type, reduce the width of the udiv/urem.
Reviewers: spatel, sanjoy
Subscribers: llvm-commits, hiraditya
Differential Revision: https://reviews.llvm.org/D44102
llvm-svn: 326898
This pretty much reverts r322006, except that we keep the test,
because we work around the issue exposed in a different way (a
recursion limit in value tracking). There's still probably some
sequence that exposes this problem, and the proper way to fix that
for somebody who has time is outlined in the code review.
llvm-svn: 323630
Summary:
See D37528 for a previous (non-deferred) version of this
patch and its description.
Preserves dominance in a deferred manner using a new class
DeferredDominance. This reduces the performance impact of
updating the DominatorTree at every edge insertion and
deletion. A user may call DDT->flush() within JumpThreading
for an up-to-date DT. This patch currently has one flush()
at the end of runImpl() to ensure DT is preserved across
the pass.
LVI is also preserved to help subsequent passes such as
CorrelatedValuePropagation. LVI is simpler to maintain and
is done immediately (not deferred). The code to perform the
preversation was minimally altered and simply marked as
preserved for the PassManager to be informed.
This extends the analysis available to JumpThreading for
future enhancements such as threading across loop headers.
Reviewers: dberlin, kuhar, sebpop
Reviewed By: kuhar, sebpop
Subscribers: mgorny, dmgreen, kuba, rnk, rsmith, hiraditya, llvm-commits
Differential Revision: https://reviews.llvm.org/D40146
llvm-svn: 322401
This is an attempt of fixing PR35807.
Due to the non-standard definition of dominance in LLVM, where uses in
unreachable blocks are dominated by anything, you can have, in an
unreachable block:
%patatino = OP1 %patatino, CONSTANT
When `SimplifyInstruction` receives a PHI where an incoming value is of
the aforementioned form, in some cases, loops indefinitely.
What I propose here instead is keeping track of the incoming values
from unreachable blocks, and replacing them with undef. It fixes this
case, and it seems to be good regardless (even if we can't prove that
the value is constant, as it's coming from an unreachable block, we
can ignore it).
Differential Revision: https://reviews.llvm.org/D41812
llvm-svn: 322006
Summary:
See D37528 for a previous (non-deferred) version of this
patch and its description.
Preserves dominance in a deferred manner using a new class
DeferredDominance. This reduces the performance impact of
updating the DominatorTree at every edge insertion and
deletion. A user may call DDT->flush() within JumpThreading
for an up-to-date DT. This patch currently has one flush()
at the end of runImpl() to ensure DT is preserved across
the pass.
LVI is also preserved to help subsequent passes such as
CorrelatedValuePropagation. LVI is simpler to maintain and
is done immediately (not deferred). The code to perfom the
preversation was minimally altered and was simply marked
as preserved for the PassManager to be informed.
This extends the analysis available to JumpThreading for
future enhancements. One example is loop boundary threading.
Reviewers: dberlin, kuhar, sebpop
Reviewed By: kuhar, sebpop
Subscribers: hiraditya, llvm-commits
Differential Revision: https://reviews.llvm.org/D40146
llvm-svn: 321825
Summary:
See D37528 for a previous (non-deferred) version of this
patch and its description.
Preserves dominance in a deferred manner using a new class
DeferredDominance. This reduces the performance impact of
updating the DominatorTree at every edge insertion and
deletion. A user may call DDT->flush() within JumpThreading
for an up-to-date DT. This patch currently has one flush()
at the end of runImpl() to ensure DT is preserved across
the pass.
LVI is also preserved to help subsequent passes such as
CorrelatedValuePropagation. LVI is simpler to maintain and
is done immediately (not deferred). The code to perfom the
preversation was minimally altered and was simply marked
as preserved for the PassManager to be informed.
This extends the analysis available to JumpThreading for
future enhancements. One example is loop boundary threading.
Reviewers: dberlin, kuhar, sebpop
Reviewed By: kuhar, sebpop
Subscribers: hiraditya, llvm-commits
Differential Revision: https://reviews.llvm.org/D40146
llvm-svn: 320612
This uses ConstantRange::makeGuaranteedNoWrapRegion's newly-added handling for subtraction to allow CVP to remove some subtraction overflow checks.
Differential Revision: https://reviews.llvm.org/D40039
llvm-svn: 319807
Summary:
This adds logic to CVP to remove some overflow checks. It uses LVI to remove
operations with at least one constant. Specifically, this can remove many
overflow intrinsics immediately following an overflow check in the source code,
such as:
if (x < INT_MAX)
... x + 1 ...
Patch by Joel Galenson!
Reviewers: sanjoy, regehr
Reviewed By: sanjoy
Subscribers: fhahn, pirama, srhines, llvm-commits
Differential Revision: https://reviews.llvm.org/D39483
llvm-svn: 317911
Summary:
This patch adds processing of binary operations when the def of operands are in
the same block (i.e. local processing).
Earlier we bailed out in such cases (the bail out was introduced in rL252032)
because LVI at that time was more precise about context at the end of basic
blocks, which implied local def and use analysis didn't benefit CVP.
Since then we've added support for LVI in presence of assumes and guards. The
test cases added show how local def processing in CVP helps adding more
information to the ashr, sdiv, srem and add operators.
Note: processCmp which suffers from the same problem will
be handled in a later patch.
Reviewers: philip, apilipenko, SjoerdMeijer, hfinkel
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D38766
llvm-svn: 315634
JumpThreading now preserves dominance and lazy value information across the
entire pass. The pass manager is also informed of this preservation with
the goal of DT and LVI being recalculated fewer times overall during
compilation.
This change prepares JumpThreading for enhanced opportunities; particularly
those across loop boundaries.
Patch by: Brian Rzycki <b.rzycki@samsung.com>,
Sebastian Pop <s.pop@samsung.com>
Differential revision: https://reviews.llvm.org/D37528
llvm-svn: 314435
Summary:
Fairly straightforward patch to fill in some of the holes in the
attributes API with respect to accessing parameter/argument attributes.
The patch aims to step further towards encapsulating the
idx+FirstArgIndex pattern to access these attributes to within the
AttributeList.
Patch by Daniel Neilson!
Reviewers: rnk, chandlerc, pete, javed.absar, reames
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D33355
llvm-svn: 304329
Summary:
Do three things to help with that:
- Add AttributeList::FirstArgIndex, which is an enumerator currently set
to 1. It allows us to change the indexing scheme with fewer changes.
- Add addParamAttr/removeParamAttr. This just shortens addAttribute call
sites that would otherwise need to spell out FirstArgIndex.
- Remove some attribute-specific getters and setters from Function that
take attribute list indices. Most of these were only used from
BuildLibCalls, and doesNotAlias was only used to test or set if the
return value is malloc-like.
I'm happy to split the patch, but I think they are probably easier to
review when taken together.
This patch should be NFC, but it sets the stage to change the indexing
scheme to this, which is more convenient when indexing into an array:
0: func attrs
1: retattrs
2...: arg attrs
Reviewers: chandlerc, pete, javed.absar
Subscribers: david2050, llvm-commits
Differential Revision: https://reviews.llvm.org/D32811
llvm-svn: 302060
This avoids the confusing 'CS.paramHasAttr(ArgNo + 1, Foo)' pattern.
Previously we were testing return value attributes with index 0, so I
introduced hasReturnAttr() for that use case.
llvm-svn: 300367
and to expose a handle to represent the actual case rather than having
the iterator return a reference to itself.
All of this allows the iterator to be used with common STL facilities,
standard algorithms, etc.
Doing this exposed some missing facilities in the iterator facade that
I've fixed and required some work to the actual iterator to fully
support the necessary API.
Differential Revision: https://reviews.llvm.org/D31548
llvm-svn: 300032
This moves it to the iterator facade utilities giving it full random
access semantics, etc. It can also now be used with standard algorithms
like std::all_of and std::any_of and range adaptors like llvm::reverse.
Also make the semantics of iterating match what every other iterator
uses and forbid decrementing past the begin iterator. This was used as
a hacky way to work around iterator invalidation. However, every
instance trying to do this failed to actually avoid touching invalid
iterators despite the clear documentation that the removed and all
subsequent iterators become invalid including the end iterator. So I've
added a return of the next iterator to removeCase and rewritten the
loops that were doing this to correctly follow the iterator pattern of
either incremneting or removing and assigning fresh values to the
iterator and the end.
In one case we were trying to go backwards to make this cleaner but it
doesn't actually work. I've made that code match the code we use
everywhere else to remove cases as we iterate. This changes the order of
cases in one test output and I moved that test to CHECK-DAG so it
wouldn't care -- the order isn't semantically meaningful anyways.
llvm-svn: 298791
Summary:
This class is a list of AttributeSetNodes corresponding the function
prototype of a call or function declaration. This class used to be
called ParamAttrListPtr, then AttrListPtr, then AttributeSet. It is
typically accessed by parameter and return value index, so
"AttributeList" seems like a more intuitive name.
Rename AttributeSetImpl to AttributeListImpl to follow suit.
It's useful to rename this class so that we can rename AttributeSetNode
to AttributeSet later. AttributeSet is the set of attributes that apply
to a single function, argument, or return value.
Reviewers: sanjoy, javed.absar, chandlerc, pete
Reviewed By: pete
Subscribers: pete, jholewinski, arsenm, dschuff, mehdi_amini, jfb, nhaehnle, sbc100, void, llvm-commits
Differential Revision: https://reviews.llvm.org/D31102
llvm-svn: 298393
While not CVP's fault, this caused miscompiles (PR31181). Reverting
until those are resolved.
(This also reverts the follow-ups r288154 and r288161 which removed the
flag.)
llvm-svn: 296030
Summary:
After the DFS order change for LVI, i have a few testcases that now
take forever.
The TL;DR - This is mainly due to the overdefined cache, but that
requires predicateinfo to fix[1]
In order to maximize reuse of the LVI cache for now, change the order
we iterate in.
This reduces my testcase from 5 minutes to 4 seconds.
I have verified cases like gmic do not get slower.
I am playing with whether the order should be postorder or idf.
[1] In practice, overdefined anywhere should be overdefined
everywhere, so this cache should be global. That also fixes this bug.
The problem, however, is that LVI relies on this cache being filled in
per-block because it wants different values in different blocks due to
precisely the naming issue that predicateinfo fixes. With
predicateinfo, making the cache global works fine on individual
passes, and also resolves this issue.
Reviewers: davide, sanjoy, chandlerc
Subscribers: llvm-commits, djasper
Differential Revision: https://reviews.llvm.org/D29679
llvm-svn: 294398
become unavailable.
The AssumptionCache is now immutable but it still needs to respond to
DomTree invalidation if it ended up caching one.
This lets us remove one of the explicit invalidates of LVI but the
other one continues to avoid hitting a latent bug.
llvm-svn: 292769
CVP doesn't care about the order of blocks visited, but by using a pre-order traversal over the graph we can a) not visit unreachable blocks and b) optimize as we go so that analysis of later blocks produce slightly more precise results.
I noticed this via inspection and don't have a concrete example which points to the issue.
llvm-svn: 290760
The flag was introduced because the optimization controlled by the flag initially caused regressions. All the regressions were fixed some time ago and the flag has been false for quite a while.
llvm-svn: 288154
An arithmetic shift can be safely changed to a logical shift if the first
operand is known positive. This allows ComputeKnownBits (and similar analysis)
to determine the sign bit of the shifted value in some cases. In turn, this
allows InstCombine to canonicalize a signed comparison (a > 0) into an equality
check (a != 0).
PR30577
Differential Revision: https://reviews.llvm.org/D25119
llvm-svn: 284013
It causes a regression on our internal benchmark. Introduce cvp-dont-process flag and set it off by default while investigating the regression.
llvm-svn: 279082