When we predicate an instruction (div, rem, store) we place the instruction in
its own basic block within the vectorized loop. If a predicated instruction has
scalar operands, it's possible to recursively sink these scalar expressions
into the predicated block so that they might avoid execution. This patch sinks
as much scalar computation as possible into predicated blocks. We previously
were able to sink such operands only if they were extractelement instructions.
Differential Revision: https://reviews.llvm.org/D25632
llvm-svn: 285097
This adds a new function to DebugInfo.cpp that takes an llvm::Module
as input and removes all debug info metadata that is not directly
needed for line tables, thus effectively stripping all type and
variable information from the module.
The primary motivation for this feature was the bitcode work flow
(cf. http://lists.llvm.org/pipermail/llvm-dev/2016-June/100643.html
for more background). This is not wired up yet, but will be in
subsequent patches. For testing, the new functionality is exposed to
opt with a -strip-nonlinetable-debuginfo option.
The secondary use-case (and one that works right now!) is as a
reduction pass in bugpoint. I added two new bugpoint options
(-disable-strip-debuginfo and -disable-strip-debug-types) to control
the new features. By default it will first attempt to remove all debug
information, then only the type info, and then proceed to hack at any
remaining MDNodes.
Thanks to Adrian Prantl for stewarding this patch!
llvm-svn: 285094
When indvars widened an induction variable, the debug location for the loop
increment computation was incorrectly set equal to the debug loc of the loop
latch terminator.
This patch fixes the issue by propagating the correct location from the
original loop increment instruction to the new widened increment.
Differential Revision: https://reviews.llvm.org/D25872
llvm-svn: 285083
Now that MemorySSA keeps track of whether MemoryUses are optimized, use
getClobberingMemoryAccess() to check MemoryUse memory dependencies since
it should no longer be so expensive.
This is a follow-up change to https://reviews.llvm.org/D25881
llvm-svn: 285080
This fixes a bug in the handling of lexical scopes, when more than one
scope is defined on the same line or functions are inlined into call
sites that are on the same line as the function definition. This
situation can easily happen in macro expansions.
The problem is solved by introducing a SmallDenseMap<DIScope *,
DILexicalBlockFile *, 1> that keeps track of all the different lexical
scopes that share a line/file location.
Fixes PR30681.
llvm-svn: 284998
Summary:
When using MemorySSA, re-optimize MemoryPhis when removing a store since
this may create MemoryPhis with all identical arguments.
Also, when using MemorySSA to check if two MemoryUses are reading from
the same version of the heap, use the defining access instead of calling
getClobberingAccess, since the latter can currently result in many more
AA calls. Once the MemorySSA use optimization tracking changes are
done, we can remove this limitation, which should result in more loads
being CSE'd.
Reviewers: dberlin
Subscribers: mcrosier, llvm-commits
Differential Revision: https://reviews.llvm.org/D25881
llvm-svn: 284984
Summary:
These are good candidates for jump threading. This enables later opts
(such as InstCombine) to combine instructions from the selects with
instructions out of the selects. SimplifyCFG will fold the select
again if unfolding wasn't worth it.
Patch by James Molloy and Pablo Barrio.
Reviewers: reames, bkramer, mcrosier, gberry, haicheng, jmolloy, sebpop
Subscribers: jojo, rengolin, llvm-commits
Differential Revision: https://reviews.llvm.org/D25477
llvm-svn: 284971
Summary:
Utility pass to remove gc.relocates created by rewrite statepoints for GC.
With respect to safepoint verification, the IR generated would be incorrect, and cannot run
as such.
This would be a single transformation on the final optimized IR.
The benefit of the pass is for easy analysis when the IRs are 'polluted' by too
many gc.relocates.
Added tests.
test run: All RS4GC tests with -verify option. Local downstream tests on large
IR files. This also works when the pointer being gc.relocated is another
gc.relocate.
Reviewers: sanjoy, reames
Subscribers: beanz, mgorny, llvm-commits
Differential Revision: https://reviews.llvm.org/D25096
llvm-svn: 284855
When we have a loop with a known upper bound on the number of iterations, and
furthermore know that either the number of iterations will be either exactly
that upper bound or zero, then we can fully unroll up to that upper bound
keeping only the first loop test to check for the zero iteration case.
Most of the work here is in plumbing this 'max-or-zero' information from the
part of scalar evolution where it's detected through to loop unrolling. I've
also gone for the safe default of 'false' everywhere but howManyLessThans which
could probably be improved.
Differential Revision: https://reviews.llvm.org/D25682
llvm-svn: 284818
There's no agreement about this patch. I personally find the
PRE machinery of the current GVN hard enough to reason about
that I'm not sure I'll try to land this again, instead of working
on the rewrite).
llvm-svn: 284796
Summary:
This allows us to mark when uses have been optimized.
This lets us avoid rewalking (IE when people call getClobberingAccess on everything), and also
enables us to later relax the requirement of use optimization during updates with less cost.
Reviewers: george.burgess.iv
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D25172
llvm-svn: 284771
All of these existed because MSVC 2013 was unable to synthesize default
move ctors. We recently dropped support for it so all that error-prone
boilerplate can go.
No functionality change intended.
llvm-svn: 284721
Some instructions from the original loop, when vectorized, can become trivially
dead. This happens because of the way we structure the new loop. For example,
we create new induction variables and induction variable "steps" in the new
loop. Thus, when we go to vectorize the original induction variable update, it
may no longer be needed due to the instructions we've already created. This
patch prevents us from creating these redundant instructions. This reduces code
size before simplification and allows greater flexibility in code generation
since we have fewer unnecessary instruction uses.
Differential Revision: https://reviews.llvm.org/D25631
llvm-svn: 284631
This change is motivated by the case when IndVarSimplify doesn't widen a comparison of IV increment because it can't prove IV increment being non-negative. We end up with a redundant trunc of the widened increment on this example.
for.body:
%i = phi i32 [ %start, %for.body.lr.ph ], [ %i.inc, %for.inc ]
%within_limits = icmp ult i32 %i, 64
br i1 %within_limits, label %continue, label %for.end
continue:
%i.i64 = zext i32 %i to i64
%arrayidx = getelementptr inbounds i32, i32* %base, i64 %i.i64
%val = load i32, i32* %arrayidx, align 4
br label %for.inc
for.inc:
%i.inc = add nsw nuw i32 %i, 1
%cmp = icmp slt i32 %i.inc, %limit
br i1 %cmp, label %for.body, label %for.end
There is a range check inside of the loop which guarantees the IV to be non-negative. NSW on the increment guarantees that the increment is also non-negative. Teach IndVarSimplify to use the range check to prove non-negativity of loop increments.
Reviewed By: sanjoy
Differential Revision: https://reviews.llvm.org/D25738
llvm-svn: 284629
Summary:
This pass shrink-wraps a condition to some library calls where the call
result is not used. For example:
sqrt(val);
is transformed to
if (val < 0)
sqrt(val);
Even if the result of library call is not being used, the compiler cannot
safely delete the call because the function can set errno on error
conditions.
Note in many functions, the error condition solely depends on the incoming
parameter. In this optimization, we can generate the condition can lead to
the errno to shrink-wrap the call. Since the chances of hitting the error
condition is low, the runtime call is effectively eliminated.
These partially dead calls are usually results of C++ abstraction penalty
exposed by inlining. This optimization hits 108 times in 19 C/C++ programs
in SPEC2006.
Reviewers: hfinkel, mehdi_amini, davidxl
Subscribers: modocache, mgorny, mehdi_amini, xur, llvm-commits, beanz
Differential Revision: https://reviews.llvm.org/D24414
llvm-svn: 284542
Summary: Debug info should *not* affect code generation. This patch properly handles debug info to make sure the generated code are the same with or without debug info.
Reviewers: davidxl, mzolotukhin, jmolloy
Subscribers: aprantl, llvm-commits
Differential Revision: https://reviews.llvm.org/D25286
llvm-svn: 284415
Not all ConstantExprs can be represented by a global variable, for example most
pointer arithmetic other than addition of a constant, so we can't convert these
values from switch statements to lookup tables.
Differential Revision: https://reviews.llvm.org/D25550
llvm-svn: 284379
In theory this could be generalized to move anything where
we prove the operands are available, but that would require
rewriting PRE. As NewGVN will hopefully come soon, and we're
trying to rewrite PRE in terms of NewGVN+MemorySSA, it's probably
not worth spending too much time on it. Fix provided by
Daniel Berlin!
llvm-svn: 284311
BasicBlock::size is O(insts), making this loop O(blocks*insts), which
can be really slow on generated code. getPrevNode already checks if
we're at the beginning of the block and returns nullptr if so, just use
that instead. No functionality change intended.
llvm-svn: 284303
- Removed unused class members.
- Made class internal data private.
- Made class scoped data function scoped where it's possible.
- Replace naked new/delete with unique_ptr.
- Made resources guaranteed to be freed.
Differential Revision: https://reviews.llvm.org/D25464
llvm-svn: 284290
Prefer add/zext because they are better supported in terms of value-tracking.
Note that the backend should be prepared for this IR canonicalization
(including vector types) after:
https://reviews.llvm.org/rL284015
Differential Revision: https://reviews.llvm.org/D25135
llvm-svn: 284241
This patch modifies the cost calculation of predicated instructions (div and
rem) to avoid the accumulation of rounding errors due to multiple truncating
integer divisions. The calculation for predicated stores will be addressed in a
follow-on patch since we currently don't scale the cost of predicated stores by
block probability.
Differential Revision: https://reviews.llvm.org/D25333
llvm-svn: 284123
This is with an extra change to avoid calling MemoryLocation::get() on a call instruction.
Differential Revision: https://reviews.llvm.org/D25542
llvm-svn: 284098
This CL didn't actually address the test case in PR30499, and clang
still crashes.
Also revert dependent change "Memory-SSA cleanup of clobbers interface, NFC"
Reverts r283965 and r283967.
llvm-svn: 284093
Reappy r284044 after revert in r284051. Krzysztof fixed the error in r284049.
The original summary:
This patch tries to fully unroll loops having break statement like this
for (int i = 0; i < 8; i++) {
if (a[i] == value) {
found = true;
break;
}
}
GCC can fully unroll such loops, but currently LLVM cannot because LLVM only
supports loops having exact constant trip counts.
The upper bound of the trip count can be obtained from calling
ScalarEvolution::getMaxBackedgeTakenCount(). Part of the patch is the
refactoring work in SCEV to prevent duplicating code.
The feature of using the upper bound is enabled under the same circumstance
when runtime unrolling is enabled since both are used to unroll loops without
knowing the exact constant trip count.
llvm-svn: 284053
This patch tries to fully unroll loops having break statement like this
for (int i = 0; i < 8; i++) {
if (a[i] == value) {
found = true;
break;
}
}
GCC can fully unroll such loops, but currently LLVM cannot because LLVM only
supports loops having exact constant trip counts.
The upper bound of the trip count can be obtained from calling
ScalarEvolution::getMaxBackedgeTakenCount(). Part of the patch is the
refactoring work in SCEV to prevent duplicating code.
The feature of using the upper bound is enabled under the same circumstance
when runtime unrolling is enabled since both are used to unroll loops without
knowing the exact constant trip count.
Differential Revision: https://reviews.llvm.org/D24790
llvm-svn: 284044
Summary:
Constant bundle operands may need to retain their constant-ness for
correctness. I'll admit that this is slightly odd, but it looks like
SimplifyCFG already does this for things like @llvm.frameaddress and
@llvm.stackmap, so I suppose adding one more case is not a big deal.
It is possible to add a mechanism to denote bundle operands that need to
remain constants, but that's probably too complicated for the time
being.
Reviewers: jmolloy
Subscribers: mcrosier, llvm-commits
Differential Revision: https://reviews.llvm.org/D25502
llvm-svn: 284028
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
As discussed by Andrea on PR30486, we have an unsafe cast to an Instruction type in the select combine which doesn't take into account that it could be a ConstantExpr instead.
Differential Revision: https://reviews.llvm.org/D25466
llvm-svn: 284000
This implements the cleanup that Danny asked to commit separately from the
previous fix to GVN-hoist in https://reviews.llvm.org/D25476#inline-219818
Tested with ninja check on x86_64-linux.
llvm-svn: 283967
This is a refreshed version of a patch that was reverted: it fixes
the problems reported in both PR30216 and PR30499, and
contains all the test-cases from both bugs.
To hoist stores past loads, we used to search for potential
conflicting loads on the hoisting path by following a MemorySSA
def-def link from the store to be hoisted to the previous
defining memory access, and from there we followed the def-use
chains to all the uses that occur on the hoisting path. The
problem is that the def-def link may point to a store that does
not alias with the store to be hoisted, and so the loads that are
walked may not alias with the store to be hoisted, and even as in
the testcase of PR30216, the loads that may alias with the store
to be hoisted are not visited.
The current patch visits all loads on the path from the store to
be hoisted to the hoisting position and uses the alias analysis
to ask whether the store may alias the load. I was not able to
use the MemorySSA functionality to ask for whether load and
store are clobbered: I'm not sure which function to call, so I
used a call to AA->isNoAlias().
Store past store is still working as before using a MemorySSA
query: I added an extra test to pr30216.ll to make sure store
past store does not regress.
Tested on x86_64-linux with check and a test-suite run.
Differential Revision: https://reviews.llvm.org/D25476
llvm-svn: 283965
For each block check that it doesn't have any uses outside of it's innermost loop.
Differential Revision: https://reviews.llvm.org/D25364
llvm-svn: 283877
When combining an integer load with !range metadata that does not include 0 to a pointer load, make sure emit !nonnull metadata on the newly-created pointer load. This prevents the !nonnull metadata from being dropped during a ptrtoint/inttoptr pair.
This fixes PR30597.
Patch by Ariel Ben-Yehuda!
Differential Revision: https://reviews.llvm.org/D25215
llvm-svn: 283836
The core of the change is supposed to be NFC, however it also fixes
what I believe was an undefined behavior when calling:
va_start(ValueArgs, Desc);
with Desc being a StringRef.
Differential Revision: https://reviews.llvm.org/D25342
llvm-svn: 283671
Summary:
If heap allocation of a coroutine is elided, we need to make sure that we will update an address stored in the coroutine frame from f.destroy to f.cleanup.
Before this change, CoroSplit synthesized these stores after coro.begin:
```
store void (%f.Frame*)* @f.resume, void (%f.Frame*)** %resume.addr
store void (%f.Frame*)* @f.destroy, void (%f.Frame*)** %destroy.addr
```
In those cases where we did heap elision, but were not able to devirtualize all indirect calls, destroy call will attempt to "free" the coroutine frame stored on the stack. Oops.
Now we use select to put an appropriate coroutine subfunction in the destroy slot. As bellow:
```
store void (%f.Frame*)* @f.resume, void (%f.Frame*)** %resume.addr
%0 = select i1 %need.alloc, void (%f.Frame*)* @f.destroy, void (%f.Frame*)* @f.cleanup
store void (%f.Frame*)* %0, void (%f.Frame*)** %destroy.addr
```
Reviewers: majnemer
Subscribers: mehdi_amini, llvm-commits
Differential Revision: https://reviews.llvm.org/D25377
llvm-svn: 283625
If we're going to canonicalize IR towards select of constants, try harder to create those.
Also, don't lose the metadata.
This is actually 4 related transforms in one patch:
// select X, (sext X), C --> select X, -1, C
// select X, (zext X), C --> select X, 1, C
// select X, C, (sext X) --> select X, C, 0
// select X, C, (zext X) --> select X, C, 0
Differential Revision: https://reviews.llvm.org/D25126
llvm-svn: 283575
Summary: -fsample-profile needs discriminator, which will not be added if built with -g0. This patch makes sure the discriminator is added for sample-profile at -g0. A followup patch will be send out to update clang tests.
Reviewers: davidxl, dblaikie, echristo, dnovillo
Subscribers: mehdi_amini, probinson, llvm-commits
Differential Revision: https://reviews.llvm.org/D25132
llvm-svn: 283565
Previously, we marked the branch conditions of latch blocks uniform after
vectorization if they were instructions contained in the loop. However, if a
condition instruction has users other than the branch, it may not remain
uniform. This patch ensures the conditions we mark uniform are only used by the
branch. This should fix PR30627.
Reference: https://llvm.org/bugs/show_bug.cgi?id=30627
llvm-svn: 283563
unrolling.
The next code is not vectorized by the SLPVectorizer:
```
int test(unsigned int *p) {
int sum = 0;
for (int i = 0; i < 8; i++)
sum += p[i];
return sum;
}
```
During optimization this loop is fully unrolled and SLPVectorizer is
unable to vectorize it. Patch tries to fix this problem.
Differential Revision: https://reviews.llvm.org/D24796
llvm-svn: 283535
With the ROPI and RWPI relocation models we can't always have pointers
to global data or functions in constant data, so don't try to convert switches
into lookup tables if any value in the lookup table would require a relocation.
We can still safely emit lookup tables of other values, such as simple
constants.
Differential Revision: https://reviews.llvm.org/D24462
llvm-svn: 283530
GetCaseResults assumed that a terminator with one successor was an
unconditional branch. This is not necessarily the case, it could be a
cleanupret.
Strengthen the check by querying whether or not the terminator is
exceptional.
llvm-svn: 283517
Add a weak alias to the renamed Comdat function in IR level instrumentation,
using it's original name. This ensures the same behavior w/ and w/o IR
instrumentation, even for non standard conforming code.
Differential Revision: http://reviews.llvm.org/D25339
llvm-svn: 283490
This adds a new function to DebugInfo.cpp that takes an llvm::Module
as input and removes all debug info metadata that is not directly
needed for line tables, thus effectively stripping all type and
variable information from the module.
The primary motivation for this feature was the bitcode work flow
(cf. http://lists.llvm.org/pipermail/llvm-dev/2016-June/100643.html
for more background). This is not wired up yet, but will be in
subsequent patches. For testing, the new functionality is exposed to
opt with a -strip-nonlinetable-debuginfo option.
The secondary use-case (and one that works right now!) is as a
reduction pass in bugpoint. I added two new bugpoint options
(-disable-strip-debuginfo and -disable-strip-debug-types) to control
the new features. By default it will first attempt to remove all debug
information, then only the type info, and then proceed to hack at any
remaining MDNodes.
llvm-svn: 283473
Summary: This makes a change to the state used to maintain visited information for depth first iterator. We know assume a method "completed(...)" which is called after all children of a node have been visited. In all existing cases, this method does nothing so this patch has no functional changes. It will however allow a client to distinguish back from cross edges in a DFS tree.
Reviewers: nadav, mehdi_amini, dberlin
Subscribers: MatzeB, mzolotukhin, twoh, freik, llvm-commits
Differential Revision: https://reviews.llvm.org/D25191
llvm-svn: 283391
The vectorizer already holds a pointer to one cost model artifact in a member
variable (i.e., MinBWs). As we add more, it will be easier to communicate these
artifacts to the vectorizer if we simply pass a pointer to the cost model
instead.
llvm-svn: 283373
The vectorizer already holds a pointer to the legality analysis in a member
variable, so it makes sense that we would pass it in the constructor.
llvm-svn: 283368
This patch refactors the cost estimation of scalarized loads and stores to
reuse getScalarizationOverhead for the cost of the extractelement and
insertelement instructions we might create. The existing code accounted for
this cost, but it was functionally equivalent to the helper function.
llvm-svn: 283364
The cost model has to estimate the probability of executing predicated blocks.
However, we currently always assume predicated blocks have a 50% chance of
executing (this value is hardcoded in several places throughout the code).
Since we always use the same value, this patch adds a helper function for
getting this uniform probability. The function simplifies some comments and
makes our assumptions more clear. In the future, we may want to extend this
with actual block probability information if it's available.
llvm-svn: 283354
This patch adds a single helper function for checking if an instruction will be
scalarized with predication. Such instructions include conditional stores and
instructions that may divide by zero. Existing checks have been updated to use
the new function.
llvm-svn: 283350
Summary: LoopSink pass uses some common function in LICM. This patch refactor the LICM code to make it usable by LoopSink pass (https://reviews.llvm.org/D22778).
Reviewers: davidxl, danielcdh, hfinkel, chandlerc
Subscribers: hfinkel, llvm-commits
Differential Revision: https://reviews.llvm.org/D24168
llvm-svn: 283134
Splitting the edge is nontrivial because of the landing pad, and we would
currently assert trying to do it.
Differential Revision: https://reviews.llvm.org/D24680
llvm-svn: 283129
Summary: Added 6 new target hooks for the vectorizer in order to filter types, handle size constraints and decide how to split chains.
Reviewers: tstellarAMD, arsenm
Subscribers: arsenm, mzolotukhin, wdng, llvm-commits, nhaehnle
Differential Revision: https://reviews.llvm.org/D24727
llvm-svn: 283099
The binder is in a specific section that "reverse" the edges in a
regular dead-stripping: the binder is live as long as a global it
references is live.
This is a big hammer that prevents LLVM from dead-stripping these,
while still allowing linker dead-stripping (with special knowledge
of the section).
Differential Revision: https://reviews.llvm.org/D24673
llvm-svn: 282988
Summary:
In the case below, %Result.i19 is defined between coro.save and coro.suspend and used after coro.suspend. We need to correctly place such a value into the coroutine frame.
```
%save = call token @llvm.coro.save(i8* null)
%Result.i19 = getelementptr inbounds %"struct.lean_future<int>::Awaiter", %"struct.lean_future<int>::Awaiter"* %ref.tmp7, i64 0, i32 0
%suspend = call i8 @llvm.coro.suspend(token %save, i1 false)
switch i8 %suspend, label %exit [
i8 0, label %await.ready
i8 1, label %exit
]
await.ready:
%val = load i32, i32* %Result.i19
```
Reviewers: majnemer
Subscribers: llvm-commits, mehdi_amini
Differential Revision: https://reviews.llvm.org/D24418
llvm-svn: 282902
Summary:
Without the fix, if there was a function inlined into the coroutine with debug information, CloneFunctionInto(NewF, &F, VMap, /*ModuleLevelChanges=*/true, Returns); would duplicate all of the debug information including the DICompileUnit.
We know use VMap to indicate that debug metadata for a File, Unit and FunctionType should not be duplicated when we creating clones that will become f.resume, f.destroy and f.cleanup.
Reviewers: majnemer
Subscribers: mehdi_amini, llvm-commits
Differential Revision: https://reviews.llvm.org/D24417
llvm-svn: 282899
Summary: Not all coro.subfn.addr intrinsics can be eliminated in CoroElide through devirtualization. Those that remain need to be lowered in CoroCleanup.
Reviewers: majnemer
Subscribers: llvm-commits, mehdi_amini
Differential Revision: https://reviews.llvm.org/D24412
llvm-svn: 282897
Summary: Debug info should *not* affect optimization decisions. This patch updates loop unroller cost model to make it not affected by debug info.
Reviewers: davidxl, mzolotukhin
Subscribers: haicheng, llvm-commits, mzolotukhin
Differential Revision: https://reviews.llvm.org/D25098
llvm-svn: 282894
Summary:
This patch is adding the support for a shadow memory with
dynamically allocated address range.
The compiler-rt needs to export a symbol containing the shadow
memory range.
This is required to support ASAN on windows 64-bits.
Reviewers: kcc, rnk, vitalybuka
Subscribers: zaks.anna, kubabrecka, dberris, llvm-commits, chrisha
Differential Revision: https://reviews.llvm.org/D23354
llvm-svn: 282881
When building the steps for scalar induction variables, we previously attempted
to determine if all the scalar users of the induction variable were uniform. If
they were, we would only emit the step corresponding to vector lane zero. This
optimization was too aggressive. We generally don't know the entire set of
induction variable users that will be scalar. We have
isScalarAfterVectorization, but this is only a conservative estimate of the
instructions that will be scalarized. Thus, an induction variable may have
scalar users that aren't already known to be scalar. To avoid emitting unused
steps, we can only check that the induction variable is uniform. This should
fix PR30542.
Reference: https://llvm.org/bugs/show_bug.cgi?id=30542
llvm-svn: 282863
Summary:
We don't want to decay hot callsites to import chains of hot
callsites. The same mechanism is used in LIPO.
Reviewers: tejohnson, eraman, mehdi_amini
Subscribers: llvm-commits, mehdi_amini
Differential Revision: https://reviews.llvm.org/D24976
llvm-svn: 282833
(Recommit after making sure IsVerbose gets properly initialized in
DiagnosticInfoOptimizationBase. See previous commit that takes care of
this.)
OptimizationRemarkAnalysis directly takes the role of the report that is
generated by LAA.
Then we need the magic to be able to turn an LAA remark into an LV
remark. This is done via a new OptimizationRemark ctor.
llvm-svn: 282813
Also, make foldSelectExtConst() a member of InstCombiner, remove
unnecessary parameters from its interface, and group visitSelectInst
helpers together in the header file.
llvm-svn: 282796
OptimizationRemarkAnalysis directly takes the role of the report that is
generated by LAA.
Then we need the magic to be able to turn an LAA remark into an LV
remark. This is done via a new OptimizationRemark ctor.
llvm-svn: 282758
Summary:
Not tunned up heuristic, but with this small heuristic there is about
+0.10% improvement on SPEC 2006
Reviewers: tejohnson, mehdi_amini, eraman
Subscribers: mehdi_amini, llvm-commits
Differential Revision: https://reviews.llvm.org/D24940
llvm-svn: 282733
The last one remaining after which emitAnalysis can be removed is when
we convert the LAA's report to a vectorization report. This requires
converting LAA to the new interface first.
llvm-svn: 282726
Summary:
The patch fixes regression caused by two earlier patches D18777 and D18867.
Reviewers: reames, sanjoy
Differential Revision: http://reviews.llvm.org/D24280
From: Li Huang
llvm-svn: 282650
This commit enables more unrolling for SystemZ by implementing the
SystemZTargetTransformInfo::getUnrollingPreferences() method.
It has been found that it is better to only unroll moderately, so the
DefaultUnrollRuntimeCount has been moved into UnrollingPreferences in order
to set this to a lower value for SystemZ (4).
Reviewers: Evgeny Stupachenko, Ulrich Weigand.
https://reviews.llvm.org/D24451
llvm-svn: 282570
There is really no reason for these to be separate.
The vectorizer started this pretty bad tradition that the text of the
missed remarks is pretty meaningless, i.e. vectorization failed. There,
you have to query analysis to get the full picture.
I think we should just explain the reason for missing the optimization
in the missed remark when possible. Analysis remarks should provide
information that the pass gathers regardless whether the optimization is
passing or not.
llvm-svn: 282542
(Re-committed after moving the template specialization under the yaml
namespace. GCC was complaining about this.)
This allows various presentation of this data using an external tool.
This was first recommended here[1].
As an example, consider this module:
1 int foo();
2 int bar();
3
4 int baz() {
5 return foo() + bar();
6 }
The inliner generates these missed-optimization remarks today (the
hotness information is pulled from PGO):
remark: /tmp/s.c:5:10: foo will not be inlined into baz (hotness: 30)
remark: /tmp/s.c:5:18: bar will not be inlined into baz (hotness: 30)
Now with -pass-remarks-output=<yaml-file>, we generate this YAML file:
--- !Missed
Pass: inline
Name: NotInlined
DebugLoc: { File: /tmp/s.c, Line: 5, Column: 10 }
Function: baz
Hotness: 30
Args:
- Callee: foo
- String: will not be inlined into
- Caller: baz
...
--- !Missed
Pass: inline
Name: NotInlined
DebugLoc: { File: /tmp/s.c, Line: 5, Column: 18 }
Function: baz
Hotness: 30
Args:
- Callee: bar
- String: will not be inlined into
- Caller: baz
...
This is a summary of the high-level decisions:
* There is a new streaming interface to emit optimization remarks.
E.g. for the inliner remark above:
ORE.emit(DiagnosticInfoOptimizationRemarkMissed(
DEBUG_TYPE, "NotInlined", &I)
<< NV("Callee", Callee) << " will not be inlined into "
<< NV("Caller", CS.getCaller()) << setIsVerbose());
NV stands for named value and allows the YAML client to process a remark
using its name (NotInlined) and the named arguments (Callee and Caller)
without parsing the text of the message.
Subsequent patches will update ORE users to use the new streaming API.
* I am using YAML I/O for writing the YAML file. YAML I/O requires you
to specify reading and writing at once but reading is highly non-trivial
for some of the more complex LLVM types. Since it's not clear that we
(ever) want to use LLVM to parse this YAML file, the code supports and
asserts that we're writing only.
On the other hand, I did experiment that the class hierarchy starting at
DiagnosticInfoOptimizationBase can be mapped back from YAML generated
here (see D24479).
* The YAML stream is stored in the LLVM context.
* In the example, we can probably further specify the IR value used,
i.e. print "Function" rather than "Value".
* As before hotness is computed in the analysis pass instead of
DiganosticInfo. This avoids the layering problem since BFI is in
Analysis while DiagnosticInfo is in IR.
[1] https://reviews.llvm.org/D19678#419445
Differential Revision: https://reviews.llvm.org/D24587
llvm-svn: 282539
LLVM developers might be surprised to learn that there are blocks
without valid insertion points (catchswitch), so it seems worth calling
that out explicitly. Also add a FIXME about what we should really be
doing if we ever need to make optimized Windows EH code debuggable.
While I'm here, make auto usage more consistent with LLVM standards and
avoid an unecessary call to insertBefore.
llvm-svn: 282521
This allows various presentation of this data using an external tool.
This was first recommended here[1].
As an example, consider this module:
1 int foo();
2 int bar();
3
4 int baz() {
5 return foo() + bar();
6 }
The inliner generates these missed-optimization remarks today (the
hotness information is pulled from PGO):
remark: /tmp/s.c:5:10: foo will not be inlined into baz (hotness: 30)
remark: /tmp/s.c:5:18: bar will not be inlined into baz (hotness: 30)
Now with -pass-remarks-output=<yaml-file>, we generate this YAML file:
--- !Missed
Pass: inline
Name: NotInlined
DebugLoc: { File: /tmp/s.c, Line: 5, Column: 10 }
Function: baz
Hotness: 30
Args:
- Callee: foo
- String: will not be inlined into
- Caller: baz
...
--- !Missed
Pass: inline
Name: NotInlined
DebugLoc: { File: /tmp/s.c, Line: 5, Column: 18 }
Function: baz
Hotness: 30
Args:
- Callee: bar
- String: will not be inlined into
- Caller: baz
...
This is a summary of the high-level decisions:
* There is a new streaming interface to emit optimization remarks.
E.g. for the inliner remark above:
ORE.emit(DiagnosticInfoOptimizationRemarkMissed(
DEBUG_TYPE, "NotInlined", &I)
<< NV("Callee", Callee) << " will not be inlined into "
<< NV("Caller", CS.getCaller()) << setIsVerbose());
NV stands for named value and allows the YAML client to process a remark
using its name (NotInlined) and the named arguments (Callee and Caller)
without parsing the text of the message.
Subsequent patches will update ORE users to use the new streaming API.
* I am using YAML I/O for writing the YAML file. YAML I/O requires you
to specify reading and writing at once but reading is highly non-trivial
for some of the more complex LLVM types. Since it's not clear that we
(ever) want to use LLVM to parse this YAML file, the code supports and
asserts that we're writing only.
On the other hand, I did experiment that the class hierarchy starting at
DiagnosticInfoOptimizationBase can be mapped back from YAML generated
here (see D24479).
* The YAML stream is stored in the LLVM context.
* In the example, we can probably further specify the IR value used,
i.e. print "Function" rather than "Value".
* As before hotness is computed in the analysis pass instead of
DiganosticInfo. This avoids the layering problem since BFI is in
Analysis while DiagnosticInfo is in IR.
[1] https://reviews.llvm.org/D19678#419445
Differential Revision: https://reviews.llvm.org/D24587
llvm-svn: 282499
Summary:
We don't currently need this facility for CFI. Disabling individual hot methods proved
to be a better strategy in Chrome.
Also, the design of the feature is suboptimal, as pointed out by Peter Collingbourne.
Reviewers: pcc
Subscribers: kcc
Differential Revision: https://reviews.llvm.org/D24948
llvm-svn: 282461
Summary:
This patch improves thinlto importer
by importing 3x larger functions that are called from hot block.
I compared performance with the trunk on spec, and there
were about 2% on povray and 3.33% on milc. These results seems
to be consistant and match the results Teresa got with her simple
heuristic. Some benchmarks got slower but I think they are just
noisy (mcf, xalancbmki, omnetpp)- running the benchmarks again with
more iterations to confirm. Geomean of all benchmarks including the noisy ones
were about +0.02%.
I see much better improvement on google branch with Easwaran patch
for pgo callsite inlining (the inliner actually inline those big functions)
Over all I see +0.5% improvement, and I get +8.65% on povray.
So I guess we will see much bigger change when Easwaran patch will land
(it depends on new pass manager), but it is still worth putting this to trunk
before it.
Implementation details changes:
- Removed CallsiteCount.
- ProfileCount got replaced by Hotness
- hot-import-multiplier is set to 3.0 for now,
didn't have time to tune it up, but I see that we get most of the interesting
functions with 3, so there is no much performance difference with higher, and
binary size doesn't grow as much as with 10.0.
Reviewers: eraman, mehdi_amini, tejohnson
Subscribers: mehdi_amini, llvm-commits
Differential Revision: https://reviews.llvm.org/D24638
llvm-svn: 282437
This patch ensures that we actually scalarize instructions marked scalar after
vectorization. Previously, such instructions may have been vectorized instead.
Differential Revision: https://reviews.llvm.org/D23889
llvm-svn: 282418
Summary:
If coroutine has no suspend points, remove heap allocation and turn a coroutine into a normal function.
Also, if a pattern is detected that coroutine resumes or destroys itself prior to coro.suspend call, turn the suspend point into a simple jump to resume or cleanup label. This pattern occurs when coroutines are used to propagate errors in functions that return expected<T>.
Reviewers: majnemer
Subscribers: mehdi_amini, llvm-commits
Differential Revision: https://reviews.llvm.org/D24408
llvm-svn: 282414
The index of the new insertelement instruction was evaluated in the
wrong way, it was considered as the index of the inserted value instead
of index of the position, where the value should be inserted.
llvm-svn: 282401
This patch fixes PR30366.
Function foldUDivShl() worked under the assumption that one of the values
in input to the function was always an instance of llvm::Instruction.
However, function visitUDivOperand() (the only user of foldUDivShl) was
clearly violating that precondition; internally, visitUDivOperand() uses pattern
matches to check the operands of a udiv. Pattern matchers for binary operators
know how to handle both Instruction and ConstantExpr values.
This patch fixes the problem in foldUDivShl(). Now we use pattern matchers
instead of explicit casts to Instruction. The reduced test case from PR30366
has been added to test file InstCombine/udiv-simplify.ll.
Differential Revision: https://reviews.llvm.org/D24565
llvm-svn: 282398
Stop looking at users of UndefValue and ConstantPointerNull in the
objective C ARC optimizers. The other users aren't actually
interesting, since they're not pointing at a particular object. I
imagine these calls could be optimized through -instcombine... maybe
they already are?
These early returns will be required at some point in the future, with a
WIP patch that asserts when someone accesses a use-list on ConstantData.
llvm-svn: 282338
Assumptions on UndefValue and ConstantPointerNull aren't relevant to
other users. Ignore them entirely to avoid wasting cycles walking
through their (possibly extremely extensive (cross-module)) use-lists.
It wasn't clear how to add a specific test for this, and it'll be
covered anyway by an eventual patch that asserts when trying to access
the use-list of an instance of ConstantData.
llvm-svn: 282334
Return early from llvm::isSafeToDestroyConstant() whenever the value
`isa<ConstantData>()`. These constants are shared across the
LLVMContext. We never really want to delete them here, and walking
their use-lists can be very expensive.
(This is motivated by an eventual goal of removing use-lists entirely
from ConstantData.)
llvm-svn: 282320
If inserting more than one constant into a vector:
define <4 x float> @foo(<4 x float> %x) {
%ins1 = insertelement <4 x float> %x, float 1.0, i32 1
%ins2 = insertelement <4 x float> %ins1, float 2.0, i32 2
ret <4 x float> %ins2
}
InstCombine could reduce that to a shufflevector:
define <4 x float> @goo(<4 x float> %x) {
%shuf = shufflevector <4 x float> %x, <4 x float> <float undef, float 1.0, float 2.0, float undef>, <4 x i32><i32 0, i32 5, i32 6, i32 3>
ret <4 x float> %shuf
}
Also, InstCombine tries to convert shuffle instruction to single insertelement, if one of the vectors is a constant vector and only a single element from this constant should be used in shuffle, i.e.
shufflevector <4 x float> %v, <4 x float> <float undef, float 1.0, float
undef, float undef>, <4 x i32> <i32 0, i32 5, i32 undef, i32 undef> ->
insertelement <4 x float> %v, float 1.0, 1
Differential Revision: https://reviews.llvm.org/D24182
llvm-svn: 282237
We already have the udiv variant of this transform, so I think this is ok for
InstCombine too even though there is an increase in IR instructions. As the
tests and TODO comments show, the transform can lead to follow-on combines.
This should fix: https://llvm.org/bugs/show_bug.cgi?id=28672
Differential Revision: https://reviews.llvm.org/D24527
llvm-svn: 282209
and also the dependent r282175 "GVN-hoist: do not dereference null pointers"
It's causing compiler crashes building Harfbuzz (PR30499).
llvm-svn: 282199
To hoist stores past loads, we used to search for potential
conflicting loads on the hoisting path by following a MemorySSA
def-def link from the store to be hoisted to the previous
defining memory access, and from there we followed the def-use
chains to all the uses that occur on the hoisting path. The
problem is that the def-def link may point to a store that does
not alias with the store to be hoisted, and so the loads that are
walked may not alias with the store to be hoisted, and even as in
the testcase of PR30216, the loads that may alias with the store
to be hoisted are not visited.
The current patch visits all loads on the path from the store to
be hoisted to the hoisting position and uses the alias analysis
to ask whether the store may alias the load. I was not able to
use the MemorySSA functionality to ask for whether load and
store are clobbered: I'm not sure which function to call, so I
used a call to AA->isNoAlias().
Store past store is still working as before using a MemorySSA
query: I added an extra test to pr30216.ll to make sure store
past store does not regress.
Differential Revision: https://reviews.llvm.org/D24517
llvm-svn: 282168
Without this patch, GVN-hoist would think that a branch instruction is a scalar instruction
and would try to value number it. The patch filters out all such kind of irrelevant instructions.
A bit frustrating is that there is no easy way to discard all those very infrequent instructions,
a bit like isa<TerminatorInst> that stands for a large family of instructions. I'm thinking that
checking for those very infrequent other instructions would cost us more in compilation time
than just letting those instructions getting numbered, so I'm still thinking that a simpler check:
if (isa<TerminatorInst>(I))
return false;
is better than listing all the other less frequent instructions.
Differential Revision: https://reviews.llvm.org/D23929
llvm-svn: 282160
The additional fix is:
When adding debug information to a lowered phi node in mem2reg
check that we have a valid insertion point after the phi for adding
the debug information.
This change addresses the issue in pr30468 where a lowered phi was
added before a catchswitch and no debug information should be added
after the phi in this case.
Differential Revision: https://reviews.llvm.org/D24797
llvm-svn: 282155
For MIPS '#' is the start of comment line. Therefore we get assembler errors if # is used in the structure names.
Differential: D24334
Reviewed by: zhaoqin
llvm-svn: 282141
Currently, we give up on loop interchange if we encounter a flow dependency
anywhere in the loop list. Worse yet, we don't even track output dependencies.
This patch updates the dependency matrix computation to track flow and output
dependencies in the same way we track anti dependencies.
This improves an internal workload by 2.2x.
Note the loop interchange pass is off by default and it can be enabled with
'-mllvm -enable-loopinterchange'
Differential Revision: https://reviews.llvm.org/D24564
llvm-svn: 282101
If we identify an instruction as uniform after vectorization, we know that we
should only use the value corresponding to the first vector lane of each unroll
iteration. However, when scalarizing such instructions, we still produce values
for the other vector lanes. This patch prevents us from generating the unused
scalars.
Differential Revision: https://reviews.llvm.org/D24275
llvm-svn: 282087
Summary: Now that we have more precise debug info, we should change back to use maximum to get basic block weight.
Reviewers: dnovillo
Subscribers: andreadb, llvm-commits
Differential Revision: https://reviews.llvm.org/D24788
llvm-svn: 282084
Summary:
This is an NFC refactoring change as a precursor to the actual fix for rematerializing in
presence of phi.
https://reviews.llvm.org/D24399
Pasted from review:
findRematerializableChainToBasePointer changed to return the root of the
chain. instead of true or false.
move the PHI matching logic into the caller by inspecting the root return value.
This includes an assertion that the alternate root is in the liveset for the
call.
Tested with current RS4GC tests.
Reviewers: reames, sanjoy
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D24780
llvm-svn: 282023
This is a follow-up to r281284. Global Variables now can have
!dbg attachements, so ASAN should clone these when generating a
sanitized copy of a global variable.
<rdar://problem/24899262>
llvm-svn: 281994
The routines llvm::ConvertDebugDeclareToDebugValue() always returned
a true value which was never checked at the call site; change the
function return type to void.
This NFC cleanup was approved in the review https://reviews.llvm.org/D23715
llvm-svn: 281964
SROA doesn't preserve the llvm.mem.parallel_loop_access metadata when it
transforms loads/stores. This patch fixes a couple occurences of this
issue.
(Partially addresses PR28981).
Differential Revision: https://reviews.llvm.org/D23549
llvm-svn: 281960
When looking at the scribus_1.3 example from https://llvm.org/bugs/show_bug.cgi?id=10584, I noticed that we were spending a large amount of time computing loop exits in LCSSA. This code appears to be written with the assumption that LoopExits are stored in the Loop and thus cheap to query. This is not true, so we should cache the result across the potentially long running loop which tends to visit a small handful of Loops.
On the particular example from 10584, this change drops the time spent in LCSSA computation by about 80%.
Differential Revision: https://reviews.llvm.org/D24509
llvm-svn: 281949
Summary: Callsites in the same basic block should share the same hotness. This patch checks for the hottest callsite in the same basic block, and use the hotness for all callsites in that basic block for early inline decisions. It also fixes the test to add "-S" so theat the "CHECK-NOT" is actually checking the content.
Reviewers: dnovillo
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D24734
llvm-svn: 281927
Summary: It does not make sense to set equal weights for all unkown branches as we have static branch prediction available.
Reviewers: dnovillo
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D24732
llvm-svn: 281912
Summary: The call target count profile is directly derived from LBR branch->target data. This is more reliable than instruction frequency profiles that could be moved across basic block boundaries. This patches uses call target count profile to annotate call instructions.
Reviewers: davidxl, dnovillo
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D24410
llvm-svn: 281911
Summary:
This patch is adding the support for a shadow memory with
dynamically allocated address range.
The compiler-rt needs to export a symbol containing the shadow
memory range.
This is required to support ASAN on windows 64-bits.
Reviewers: kcc, rnk, vitalybuka
Subscribers: kubabrecka, dberris, llvm-commits, chrisha
Differential Revision: https://reviews.llvm.org/D23354
llvm-svn: 281908
When phi nodes are created in the -mem2reg phase, the @llvm.dbg.declare
entries are converted to @llvm.dbg.value entries at the place where the
store instructions existed. However no entry is created to describe
the resulting value of the phi node.
The effect of this is especially noticeable in for loops which have a
constant for the intial value; the loop control variable's location
would be described as the intial constant value in the loop body once
the -mem2reg optimization phase was run.
This change adds the creation of the @llvm.dbg.value entries to describe
variables whose location is the result of a phi node created in -mem2reg.
Also when the phi node is finally lowered to a machine instruction it
is important that the lowered "load" instruction is placed before the
associated DEBUG_VALUE entry describing the value loaded.
Differential Revision: https://reviews.llvm.org/D23715
llvm-svn: 281895
We were updating metadata but not IR flags. Because we pick an arbitrary instruction to be the CSE candidate, it comes down to luck (50% or less chance) if this results in broken codegen or not, which is why PR30373 which is actually not the fault of the commit it was bisected down to.
Fixes PR30373.
llvm-svn: 281889
Summary: Previously we reline on inst-combine to remove inlinable invoke instructions. This causes trouble because a few extra optimizations are schedule early that could introduce too much CFG change (e.g. simplifycfg removes too much control flow). This patch handles invoke instruction in-place during sample profile annotation, so that we do not rely on instcombine to remove those invoke instructions.
Reviewers: davidxl, dnovillo
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D24409
llvm-svn: 281870
Simplified GEP cloning in vectorizeMemoryInstruction().
Added an assertion that checks consecutive GEP, which should have only one loop-variant operand.
Differential Revision: https://reviews.llvm.org/D24557
llvm-svn: 281851
Summary:
This fixes an issue when files are compiled with -flto=thin
at default -O0. We need to rename anonymous globals before attempting
to write the module summary because all values need names for
the summary. This was happening at -O1 and above, but not before
the early exit when constructing the pipeline for -O0.
Also add an internal -prepare-for-thinlto option to enable this
to be tested via opt.
Fixes PR30419.
Reviewers: mehdi_amini
Subscribers: probinson, llvm-commits, mehdi_amini
Differential Revision: https://reviews.llvm.org/D24701
llvm-svn: 281840
The ValueSymbolTable is used to detect name conflict and rename
instructions automatically. This is not needed when the value
names are automatically discarded by the LLVMContext.
No functional change intended, just saving a little bit of memory.
This is a recommit of r281806 after fixing the accessor to return
a pointer instead of a reference and updating all the call-sites.
llvm-svn: 281813
computeKnownBits() already works for integer vectors, so allow vector types when calling that from InstCombine.
I don't think the change to use m_APInt in computeKnownBits is strictly necessary because we do check for
ConstantVector later, but it's more efficient to handle the splat case without needing to loop on vector elements.
This should work with InstSimplify, but doesn't yet, so I made that a FIXME comment on the test for PR24942:
https://llvm.org/bugs/show_bug.cgi?id=24942
Differential Revision: https://reviews.llvm.org/D24677
llvm-svn: 281777
A follow-up patch will rename this pass and the source file accordingly,
but I figured the non-NFC change will be easier to spot in isolation.
Differential Revision: https://reviews.llvm.org/D24641
llvm-svn: 281744
These 2 helper functions were already using APInt internally, so just
change the API and caller to allow folds for splats. The scalar
regression tests look quite thorough, so I just added a couple of
tests to prove that vectors are handled too.
These folds should be grouped with the other cmp+shift folds though.
That can be an NFC follow-up.
llvm-svn: 281663
GlobalOpt is already dead-code-eliminating global definitions. With
this change it also takes care of declarations.
Hopefully this should make it now a strict superset of GlobalDCE.
This is important for LTO/ThinLTO as we don't want the linker to see
"undefined reference" when it processes the input files: it could
prevent proper internalization (or even load an extra file from a
static archive, changing the behavior of the program!).
llvm-svn: 281653
This pattern is matched in foldICmpBinOpEqualityWithConstant() and already works
with vectors too. I changed some comments over there to point out the current
location. The tests for this transform are currently in 'sub.ll'.
Note that the remaining folds in this block all require a sub too, so they should
get grouped with the other icmp(sub) patterns.
llvm-svn: 281627
Summary: The return value of `maybeInsertAsanInitAtFunctionEntry` is ignored.
Reviewers: rnk
Subscribers: llvm-commits, chrisha, dberris
Differential Revision: https://reviews.llvm.org/D24568
llvm-svn: 281620
This is a big glob of transforms that probably should work for vectors,
but currently they are disallowed because of ConstantInt guards.
llvm-svn: 281614
Summary:
Function __asan_default_options is called by __asan_init before the
shadow memory got initialized. Instrumenting that function may lead
to flaky execution.
As the __asan_default_options is provided by users, we cannot expect
them to add the appropriate function atttributes to avoid
instrumentation.
Reviewers: kcc, rnk
Subscribers: dberris, chrisha, llvm-commits
Differential Revision: https://reviews.llvm.org/D24566
llvm-svn: 281503
This patch moves the processing of pointer induction variables in
collectLoopUniforms from the consecutive pointer phase of the analysis to the
phi node phase. Previously, if a pointer induction variable was used by both a
scalarized non-memory instruction as well as a vectorized memory instruction,
we would incorrectly identify the pointer as uniform. Pointer induction
variables should be treated the same as other phi nodes. That is, they are
uniform if all users of the induction variable and induction variable update
are uniform.
Differential Revision: https://reviews.llvm.org/D24511
llvm-svn: 281485
The '-asan-use-private-alias’ option (disabled by default) option is currently only enabled for Linux and ELF, but it also works on Darwin and Mach-O. This option also fixes a known problem with LTO on Darwin (https://github.com/google/sanitizers/issues/647). This patch enables the support for Darwin (but still keeps it off by default) and adds the LTO test case.
Differential Revision: https://reviews.llvm.org/D24292
llvm-svn: 281470
ObjC library call with call return.
ARC contraction tries to replace uses of an argument passed to an
objective-c library call with the call return value. For example, in the
following IR, it replaces uses of argument %9 and uses of the values
discovered traversing the chain upwards (%7 and %8) with the call return
%10, if they are dominated by the call to @objc_autoreleaseReturnValue.
This transformation enables code-gen to tail-call the call to
@objc_autoreleaseReturnValue, which is necessary to enable auto release
return value optimization.
%7 = tail call i8* @objc_loadWeakRetained(i8** %6)
%8 = bitcast i8* %7 to %0*
%9 = bitcast %0* %8 to i8*
%10 = tail call i8* @objc_autoreleaseReturnValue(i8* %9)
ret %0* %8
Since r276727, llvm started removing redundant bitcasts and as a result
started feeding the following IR to ARC contraction:
%7 = tail call i8* @objc_loadWeakRetained(i8** %6)
%8 = bitcast i8* %7 to %0*
%9 = tail call i8* @objc_autoreleaseReturnValue(i8* %7)
ret %0* %8
ARC contraction no longer does the optimization described above since it
only traverses the chain upwards and fails to recognize that the
function return can be replaced by the call return. This commit changes
ARC contraction to traverse the chain downwards too and replace uses of
bitcasts with the call return.
rdar://problem/28011339
Differential Revision: https://reviews.llvm.org/D24523
llvm-svn: 281419
Teach SimplifyLibcalls that in can treat functions annotated with
apcs, aapcs or aapcs_vfp like normal C functions if they only take
and return integer or pointer values, and the target is not iOS.
Differential Revision: https://reviews.llvm.org/D24453
llvm-svn: 281322
This patch reverses the edge from DIGlobalVariable to GlobalVariable.
This will allow us to more easily preserve debug info metadata when
manipulating global variables.
Fixes PR30362. A program for upgrading test cases is attached to that
bug.
Differential Revision: http://reviews.llvm.org/D20147
llvm-svn: 281284
Trying to infer the 'returned' attribute if an argument is already
'returned' can lead to verification failure: inference might determine
that a different argument is passed through which would result in two
different arguments marked as 'returned'.
This fixes PR30350.
llvm-svn: 281221
This should *actually* fix PR30244. This cranks up the workaround for PR30188 so that we never sink loads or stores of allocas.
The idea is that these should be removed by SROA/Mem2Reg, and any movement of them may well confuse SROA or just cause unwanted code churn. It's not ideal that the midend should be crippled like this, but that unwanted churn can really cause significant regressions in important workloads (tsan).
llvm-svn: 281162
Exposed by PR30244, we will split a block currently if we think we can sink at least one instruction. However this isn't right - the reason we split predecessors is so that we can sink instructions that otherwise couldn't be sunk because it isn't safe to do so - stores, for example.
So, change the heuristic to only split if it thinks it can sink at least one non-speculatable instruction.
Should fix PR30244.
llvm-svn: 281160
Everything under foldICmpInstWithConstant() should now be working for
splat vectors via m_APInt matchers. Ie, I've removed all of the FIXMEs
that I added while cleaning that section up. Note that not all of the
associated FIXMEs in the regression tests are gone though, because some
of the tests require earlier folds that are still scalar-only.
llvm-svn: 281139
Summary:
Could be useful for comparison when we suspect that alloca was skipped
because of this.
Reviewers: eugenis
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D24437
llvm-svn: 281126
This would create a bitcast use which fails the verifier: swifterror values may
only be used by loads, stores, and as function arguments.
rdar://28233244
llvm-svn: 281114
Summary:
If one of the uses of the value is a single edge PHINode, handle it.
Original:
%val = something
<suspend>
%p = PHINode [%val]
After Spill + Part13:
%val = something
%slot = gep val.spill.slot
store %val, %slot
<suspend>
%p = load %slot
Plus tiny fixes/changes:
* use correct index for coro.free in CoroCleanup
* fixup id parameter in coro.free to allow authoring coroutine in plain C with __builtins
Reviewers: majnemer
Subscribers: mehdi_amini, llvm-commits
Differential Revision: https://reviews.llvm.org/D24242
llvm-svn: 281020
Summary: The hoisted instruction is executed speculatively. It could affect the debugging experience as user would see gdb go into code that may not be expected to execute. It will also affect sample profile accuracy by assigning incorrect frequency to source within then/else branch.
Reviewers: davidxl, dblaikie, chandlerc, kcc, echristo
Subscribers: mehdi_amini, probinson, eric_niebler, andreadb, llvm-commits
Differential Revision: https://reviews.llvm.org/D24164
llvm-svn: 280995
The test case included in r280979 wasn't checking what it was supposed to be
checking for the predicated store case. Fixing the test revealed that the
multi-use case (when a pointer is used by both vectorized and scalarized memory
accesses) wasn't being handled properly. We can't skip over
non-consecutive-like pointers since they may have looked consecutive-like with
a different memory access.
llvm-svn: 280992
Previously, all consecutive pointers were marked uniform after vectorization.
However, if a consecutive pointer is used by a memory access that is eventually
scalarized, the pointer won't remain uniform after all. An example is
predicated stores. Even though a predicated store may be consecutive, it will
still be scalarized, making it's pointer operand non-uniform.
This patch updates the logic in collectLoopUniforms to consider the cases where
a memory access may be scalarized. If a memory access may be scalarized, its
pointer operand is not marked uniform. The determination of whether a given
memory instruction will be scalarized or not has been moved into a common
function that is used by the vectorizer, cost model, and legality analysis.
Differential Revision: https://reviews.llvm.org/D24271
llvm-svn: 280979
I introduced this potential bug by missing this diff in:
https://reviews.llvm.org/rL280873
...however, I'm not sure how to reach this code path with a regression test.
We may be able to remove this code and assume that the transform to a constant
is always handled by InstSimplify?
llvm-svn: 280964
Refactor replaceDominatedUsesWith to have a flag to control whether to replace uses in BB itself.
Summary: This is in preparation for LoopSink pass which calls replaceDominatedUsesWith to update after sinking.
llvm-svn: 280949
Summary:
C allows to jump over variables declaration so lifetime.start can be
avoid before variable usage. To avoid false-positives on such rare cases
we detect them and remove from lifetime analysis.
PR27453
PR28267
Reviewers: eugenis
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D24321
llvm-svn: 280907
Summary:
When cloning blocks for prologue/epilogue we need to replicate the loop
structure from the original loop. It wasn't a problem for the innermost
loops, but it led to an incorrect loop info when we unrolled a loop with
a child loop - in this case created prologue-loop had a child loop, but
loop info didn't reflect that.
This fixes PR28888.
Reviewers: chandlerc, sanjoy, hfinkel
Subscribers: llvm-commits, silvas
Differential Revision: https://reviews.llvm.org/D24203
llvm-svn: 280901
Summary:
C allows to jump over variables declaration so lifetime.start can be
avoid before variable usage. To avoid false-positives on such rare cases
we detect them and remove from lifetime analysis.
PR27453
PR28267
Reviewers: eugenis
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D24321
llvm-svn: 280880
We can't create metadata-valued PHIs; don't try to do so when sinking.
I created a test case for this using the @llvm.type.test intrinsic, because it
takes a metadata parameter and does not have severe side effects (thus
SimplifyCFG is willing to otherwise sink it).
Previously, running the test case would crash with:
Invalid use of metadata!
%.sink = select i1 %flag, metadata <...>, metadata <0x4e45dc0>
LLVM ERROR: Broken function found, compilation aborted!
llvm-svn: 280866
This is a revert of r280676 which was a revert of r280637;
ie, this is r280637 again. It was speculatively reverted to
help debug buildbot failures.
llvm-svn: 280861
Summary:
LSV replaces multiple adjacent loads with one vectorized load and a
bunch of extractelement instructions. This patch makes the
extractelement instructions' names match those of the original loads,
for (hopefully) improved readability.
Reviewers: asbirlea, tstellarAMD
Subscribers: arsenm, mzolotukhin
Differential Revision: https://reviews.llvm.org/D23748
llvm-svn: 280818
This fixes a similar issue to the one already fixed by r280804
(revieved in D24256). Revision 280804 fixed the problem with unsafe dyn_casts
in the extrq/extrqi combining logic. However, it turns out that even the
insertq/insertqi logic was affected by the same problem.
llvm-svn: 280807
This patch fixes an assertion failure caused by unsafe dynamic casts on the
constant operands of sse4a intrinsic calls to extrq/extrqi
The combine logic that simplifies sse4a extrq/extrqi intrinsic calls currently
checks if the input operands are constants. Internally, that logic relies on
dyn_casts of values returned by calls to method Constant::getAggregateElement.
However, method getAggregateElemet may return nullptr if the constant element
cannot be retrieved. So, all the dyn_casts can potentially fail. This is what
happens for example if a constexpr value is passed in input to an extrq/extrqi
intrinsic call.
This patch fixes the problem by using a dyn_cast_or_null (instead of a simple
dyn_cast) on the result of each call to Constant::getAggregateElement.
Added reproducible test cases to x86-sse4a.ll.
Differential Revision: https://reviews.llvm.org/D24256
llvm-svn: 280804
This reverts commit r280796, as it broke the AArch64 bots for no reason.
The tests were passing and we should try to keep them passing, so a proper
review should make that happen.
llvm-svn: 280802
In failure cases it's not guaranteed that the PHI we're inspecting is actually in the successor block! In this case we need to bail out early, and never query getIncomingValueForBlock() as that will cause an assert.
llvm-svn: 280794
I should have realised this the first time around, but if we're avoiding sinking stores where the operands come from allocas so they don't create selects, we also have to do the same for loads because SROA will be just as defective looking at loads of selected addresses as stores.
Fixes PR30188 (again).
llvm-svn: 280792
PR30292 showed a case where our PHI checking wasn't correct. We were checking that all values were used by the same PHI before deciding to sink, but we weren't checking that the incoming values for that PHI were what we expected. As a result, we had to bail out after block splitting which caused us to never reach a steady state in SimplifyCFG.
Fixes PR30292.
llvm-svn: 280790
Currently the pass updates branch weights in the IR if the function has
any PGO info (entry frequency is set). However we could still have
regions of the CFG that does not have branch weights collected (e.g. a
cold region). In this case we'd use static estimates. Since static
estimates for branches are determined independently, they are
inconsistent. Updating them can "randomly" inflate block frequencies.
I've run into this in a completely cold loop of h264ref from
SPEC. -Rpass-with-hotness showed the loop to be completely cold during
inlining (before JT) but completely hot during vectorization (after JT).
The new testcase demonstrate the problem. We check array elements
against 1, 2 and 3 in a loop. The check against 3 is the loop-exiting
check. The block names should be self-explanatory.
In this example, jump threading incorrectly updates the weight of the
loop-exiting branch to 0, drastically inflating the frequency of the
loop (in the range of billions).
There is no run-time profile info for edges inside the loop, so branch
probabilities are estimated. These are the resulting branch and block
frequencies for the loop body:
check_1 (16)
(8) / |
eq_1 | (8)
\ |
check_2 (16)
(8) / |
eq_2 | (8)
\ |
check_3 (16)
(1) / |
(loop exit) | (15)
|
(back edge)
First we thread eq_1 -> check_2 to check_3. Frequencies are updated to
remove the frequency of eq_1 from check_2 and then from the false edge
leaving check_2. Changed frequencies are highlighted with * *:
check_1 (16)
(8) / |
eq_1~ | (8)
/ |
/ check_2 (*8*)
/ (8) / |
\ eq_2 | (*0*)
\ \ |
` --- check_3 (16)
(1) / |
(loop exit) | (15)
|
(back edge)
Next we thread eq_1 -> check_3 and eq_2 -> check_3 to check_1 as new
back edges. Frequencies are updated to remove the frequency of eq_1 and
eq_3 from check_3 and then the false edge leaving check_3 (changed
frequencies are highlighted with * *):
check_1 (16)
(8) / |
eq_1~ | (8)
/ |
/ check_2 (*8*)
/ (8) / |
/-- eq_2~ | (*0*)
(back edge) |
check_3 (*0*)
(*0*) / |
(loop exit) | (*0*)
|
(back edge)
As a result, the loop exit edge ends up with 0 frequency which in turn makes
the loop header to have maximum frequency.
There are a few potential problems here:
1. The profile data seems odd. There is a single profile sample of the
loop being entered. On the other hand, there are no weights inside the
loop.
2. Based on static estimation we shouldn't set edges to "extreme"
values, i.e. extremely likely or unlikely.
3. We shouldn't create profile metadata that is calculated from static
estimation. I am not sure what policy is but it seems to make sense to
treat profile metadata as something that is known to originate from
profiling. Estimated probabilities should only be reflected in BPI/BFI.
Any one of these would probably fix the immediate problem. I went for 3
because I think it's a good policy to have and added a FIXME about 2.
Differential Revision: https://reviews.llvm.org/D24118
llvm-svn: 280713
Summary:
Move early uses of spilled variables after CoroBegin.
For example, if a parameter had address taken, we may end up with the code
like:
define @f(i32 %n) {
%n.addr = alloca i32
store %n, %n.addr
...
call @coro.begin
This patch fixes the problem by moving uses of spilled variables after CoroBegin.
Reviewers: majnemer
Subscribers: mehdi_amini, llvm-commits
Differential Revision: https://reviews.llvm.org/D24234
llvm-svn: 280678
Summary:
A frontend may designate a particular suspend to be final, by setting the second argument of the coro.suspend intrinsic to true. Such a suspend point has two properties:
* it is possible to check whether a suspended coroutine is at the final suspend point via coro.done intrinsic;
* a resumption of a coroutine stopped at the final suspend point leads to undefined behavior. The only possible action for a coroutine at a final suspend point is destroying it via coro.destroy intrinsic.
This patch adds final suspend handling logic to CoroEarly and CoroSplit passes.
Now, the final suspend point example from docs\Coroutines.rst compiles and produces expected result (see test/Transform/Coroutines/ex5.ll).
Reviewers: majnemer
Subscribers: mehdi_amini, llvm-commits
Differential Revision: https://reviews.llvm.org/D24068
llvm-svn: 280646
The transform in question:
icmp (and (trunc W), C2), C1 -> icmp (and W, C2'), C1'
...is still not enabled for vectors, thus no functional change intended.
It's not clear to me if this is a good transform for vectors or even
scalars in general. Changing that behavior may be a follow-on patch.
llvm-svn: 280627
memcpy with ld/st.
When InstCombine replaces a memcpy with loads+stores it does not copy over the
llvm.mem.parallel_loop_access from the memcpy instruction. This patch fixes
that.
Differential Revision: https://reviews.llvm.org/D23499
llvm-svn: 280617
