Commit Graph

5610 Commits

Author SHA1 Message Date
Sidharth Baveja d81d9e8b86 [SplitEdge] Update SplitCriticalEdge to return a nullptr only when the edge is not critical
Summary:
The function SplitCriticalEdge (called by SplitEdge) can return a nullptr in
cases where the edge is a critical. SplitEdge uses SplitCriticalEdge assuming it
can always split all critical edges, which is an incorrect assumption.

The three cases where the function SplitCriticalEdge will return a nullptr is:
1. DestBB is an exception block
2. Options.IgnoreUnreachableDests is set to true and
isa(DestBB->getFirstNonPHIOrDbgOrLifetime()) is not equal to a nullptr
3. LoopSimplify form must be preserved (Options.PreserveLoopSimplify is true)
and it cannot be maintained for a loop due to indirect branches

For each of these situations they are handled in the following way:
1. Modified the function ehAwareSplitEdge originally from
llvm/lib/Transforms/Coroutines/CoroFrame.cpp to handle the cases when the DestBB
is an exception block. This function is called directly in SplitEdge.
SplitEdge does not call SplitCriticalEdge in this case
2. Options.IgnoreUnreachableDests is set to false by default, so this situation
does not apply.
3. Return a nullptr in this situation since the SplitCriticalEdge also returned
nullptr. Nothing we can do in this case.

Reviewed By: asbirlea

Differential Revision:https://reviews.llvm.org/D94619
2021-04-06 21:24:40 +00:00
Philip Reames 908215b346 Use AssumeInst in a few more places [nfc]
Follow up to a6d2a8d6f5.  These were found by simply grepping for "::assume", and are the subset of that result which looked cleaner to me using the isa/dyn_cast patterns.
2021-04-06 13:18:53 -07:00
Philip Reames 9ef6aa020b Plumb AssumeInst through operand bundle apis [nfc]
Follow up to a6d2a8d6f5.  This covers all the public interfaces of the bundle related code.  I tried to cleanup the internals where the changes were obvious, but there's definitely more room for improvement.
2021-04-06 12:53:53 -07:00
Philip Reames a6d2a8d6f5 Add a subclass of IntrinsicInst for llvm.assume [nfc]
Add the subclass, update a few places which check for the intrinsic to use idiomatic dyn_cast, and update the public interface of AssumptionCache to use the new class.  A follow up change will do the same for the newer assumption query/bundle mechanisms.
2021-04-06 11:16:22 -07:00
Benjamin Kramer ce4acb01b3 Avoid unused variable warning in Release builds 2021-04-06 16:25:19 +02:00
Kerry McLaughlin 7344f3d39a [LoopVectorize] Add strict in-order reduction support for fixed-width vectorization
Previously we could only vectorize FP reductions if fast math was enabled, as this allows us to
reorder FP operations. However, it may still be beneficial to vectorize the loop by moving
the reduction inside the vectorized loop and making sure that the scalar reduction value
be an input to the horizontal reduction, e.g:

  %phi = phi float [ 0.0, %entry ], [ %reduction, %vector_body ]
  %load = load <8 x float>
  %reduction = call float @llvm.vector.reduce.fadd.v8f32(float %phi, <8 x float> %load)

This patch adds a new flag (IsOrdered) to RecurrenceDescriptor and makes use of the changes added
by D75069 as much as possible, which already teaches the vectorizer about in-loop reductions.
For now in-order reduction support is off by default and controlled with the `-enable-strict-reductions` flag.

Reviewed By: david-arm

Differential Revision: https://reviews.llvm.org/D98435
2021-04-06 14:45:34 +01:00
Abhina Sreeskantharajan 82b3e28e83 [SystemZ][z/OS][Windows] Add new OF_TextWithCRLF flag and use this flag instead of OF_Text
Problem:
On SystemZ we need to open text files in text mode. On Windows, files opened in text mode adds a CRLF '\r\n' which may not be desirable.

Solution:
This patch adds two new flags

  - OF_CRLF which indicates that CRLF translation is used.
  - OF_TextWithCRLF = OF_Text | OF_CRLF indicates that the file is text and uses CRLF translation.

Developers should now use either the OF_Text or OF_TextWithCRLF for text files and OF_None for binary files. If the developer doesn't want carriage returns on Windows, they should use OF_Text, if they do want carriage returns on Windows, they should use OF_TextWithCRLF.

So this is the behaviour per platform with my patch:

z/OS:
OF_None: open in binary mode
OF_Text : open in text mode
OF_TextWithCRLF: open in text mode

Windows:
OF_None: open file with no carriage return
OF_Text: open file with no carriage return
OF_TextWithCRLF: open file with carriage return

The Major change is in llvm/lib/Support/Windows/Path.inc to only set text mode if the OF_CRLF is set.
```
  if (Flags & OF_CRLF)
    CrtOpenFlags |= _O_TEXT;
```

These following files are the ones that still use OF_Text which I left unchanged. I modified all these except raw_ostream.cpp in recent patches so I know these were previously in Binary mode on Windows.
./llvm/lib/Support/raw_ostream.cpp
./llvm/lib/TableGen/Main.cpp
./llvm/tools/dsymutil/DwarfLinkerForBinary.cpp
./llvm/unittests/Support/Path.cpp
./clang/lib/StaticAnalyzer/Core/HTMLDiagnostics.cpp
./clang/lib/Frontend/CompilerInstance.cpp
./clang/lib/Driver/Driver.cpp
./clang/lib/Driver/ToolChains/Clang.cpp

Reviewed By: MaskRay

Differential Revision: https://reviews.llvm.org/D99426
2021-04-06 07:23:31 -04:00
Nikita Popov 9bad7de9a3 [SimplifyCFG] Handle two equal cases in switch to select
When converting a switch with two cases and a default into a
select, also handle the denegerate case where two cases have the
same value.

Generate this case directly as

  %or = or i1 %cmp1, %cmp2
  %res = select i1 %or, i32 %val, i32 %default

rather than

  %sel1 = select i1 %cmp1, i32 %val, i32 %default
  %res = select i1 %cmp2, i32 %val, i32 %sel1

as InstCombine is going to canonicalize to the former anyway.
2021-04-04 17:27:28 +02:00
qixingxue 62b74f7564 [GVN][NFC] Refactor analyzeLoadFromClobberingWrite
This commit adjusts the order of two swappable if statements to
make code cleaner.

Reviewed By: lattner, nikic
Differential Revision: https://reviews.llvm.org/D99648
2021-04-01 08:35:35 +08:00
Roman Lebedev 43ded90094
[NFC][LoopRotation] Count the number of instructions hoisted/cloned into preheader 2021-03-31 23:27:36 +03:00
Krasimir Georgiev c51e91e046 Revert "[Passes] Add relative lookup table converter pass"
This reverts commit 5178ffc7cf.

Compiling `llvm-profdata` with a compiler build from this produces a
crashing binary.
2021-03-30 14:13:37 +02:00
Gulfem Savrun Yeniceri 5178ffc7cf [Passes] Add relative lookup table converter pass
Lookup tables generate non PIC-friendly code, which requires dynamic relocation as described in:
https://bugs.llvm.org/show_bug.cgi?id=45244

This patch adds a new pass that converts lookup tables to relative lookup tables to make them PIC-friendly.

Differential Revision: https://reviews.llvm.org/D94355
2021-03-29 21:53:32 +00:00
Matt Arsenault 9a0c9402fa Reapply "OpaquePtr: Turn inalloca into a type attribute"
This reverts commit 07e46367ba.
2021-03-29 08:55:30 -04:00
Jingu Kang e4abb64100 [LoopUnswitch] Use reference variables instead of pointer one
Differential Revision: https://reviews.llvm.org/D99496
2021-03-29 13:08:46 +01:00
Hans Wennborg c6e5c4654b Don't use $ as suffix for symbol names in ThinLTOBitcodeWriter and other places
Using $ breaks demangling of the symbols. For example,

$ c++filt _Z3foov\$123
_Z3foov$123

This causes problems for developers who would like to see nice stack traces
etc., but also for automatic crash tracking systems which try to organize
crashes based on the stack traces.

Instead, use the period as suffix separator, since Itanium demanglers normally
ignore such suffixes:

$ c++filt _Z3foov.123
foo() [clone .123]

This is already done in some places; try to do it everywhere.

Differential revision: https://reviews.llvm.org/D97484
2021-03-29 13:03:52 +02:00
Oliver Stannard 07e46367ba Revert "Reapply "OpaquePtr: Turn inalloca into a type attribute""
Reverting because test 'Bindings/Go/go.test' is failing on most
buildbots.

This reverts commit fc9df30991.
2021-03-29 11:32:22 +01:00
Jingu Kang cfe87d4edd [NFC][LoopUnswitch] Move hasPartialIVCondition to LoopUtils
Differential revision: https://reviews.llvm.org/D99490
2021-03-29 10:29:45 +01:00
Matt Arsenault fc9df30991 Reapply "OpaquePtr: Turn inalloca into a type attribute"
This reverts commit 20d5c42e0e.
2021-03-28 13:35:21 -04:00
Nico Weber 20d5c42e0e Revert "OpaquePtr: Turn inalloca into a type attribute"
This reverts commit 4fefed6563.
Broke check-clang everywhere.
2021-03-28 13:02:52 -04:00
Matt Arsenault 4fefed6563 OpaquePtr: Turn inalloca into a type attribute
I think byval/sret and the others are close to being able to rip out
the code to support the missing type case. A lot of this code is
shared with inalloca, so catch this up to the others so that can
happen.
2021-03-28 11:12:23 -04:00
Juneyoung Lee 05884d3b52 Make FoldBranchToCommonDest poison-safe by default
This is a small patch to make FoldBranchToCommonDest poison-safe by default.
After fc3f0c9c, only two syntactic changes are needed to fix unit tests.
This does not cause any assembly difference in testsuite as well (-O3, X86-64 Manjaro).

Reviewed By: nikic

Differential Revision: https://reviews.llvm.org/D99452
2021-03-27 19:05:12 +09:00
Roman Lebedev 1c55dcbca7
[NFCI][SimplifyCFG] Don't pay for a Small{Map,Set}Vector when plain SmallSet will suffice
This *only* changes the cases where we *really* don't care
about the iteration order of the underlying contained,
namely when we will use the values from it to form DTU updates.
2021-03-25 23:25:40 +03:00
Roman Lebedev 2070fe7144
[NFCI][SimplifyCFG] Don't form DTU updates if we aren't going to apply them
I think we may want to have a thin wrapper over a vector to deduplicate
those `if(DTU)` predicates, and instead do them in the `insert()` itself.
2021-03-25 00:02:37 +03:00
Gulfem Savrun Yeniceri 5fbe1fdf17 Revert "[Passes] Add relative lookup table converter pass"
This reverts commit 5fd001a5ff
because it broke clang-with-thin-lto-ubuntu bot.
2021-03-24 18:59:33 +00:00
Gulfem Savrun Yeniceri 5fd001a5ff [Passes] Add relative lookup table converter pass
Lookup tables generate non PIC-friendly code, which requires dynamic relocation as described in:
https://bugs.llvm.org/show_bug.cgi?id=45244

This patch adds a new pass that converts lookup tables to relative lookup tables to make them PIC-friendly.

Differential Revision: https://reviews.llvm.org/D94355
2021-03-24 17:31:18 +00:00
Roman Lebedev fe36b834db
[NFCI][SimplifyCFG] Fold branch to common dest: don't check cost if no qualified preds 2021-03-24 19:01:47 +03:00
Roman Lebedev b5822026dd
[SimplifyCFG] 'Fold branch to common dest': don't overestimate the cost
`FoldBranchToCommonDest()` has a certain budget (`-bonus-inst-threshold=`)
for bonus instruction duplication. And currently it calculates the cost
as-if it will actually duplicate into each predecessor.

But ignoring the budget, it won't always duplicate into each predecessor,
there are some correctness and profitability checks.
So when calculating the cost, we should first check into which blocks
will we *actually* duplicate, and only then use that block count
to do budgeting.
2021-03-23 18:30:26 +03:00
Roman Lebedev 514bc01ca3
[SimplifyCFG] FoldBranchToCommonDest(): properly handle same-block external uses (PR49510/PR49689)
We clone bonus instructions to the end of the predecessor block,
and then use `SSAUpdater::RewriteUseAfterInsertions()`.
But that only deals with the cases where the use-to-be-rewritten
are either in different block from the def, or come after the def.

But in some loop cases, the external use may be in the beginning of
predecessor block, before the newly cloned bonus instruction.
`SSAUpdater::RewriteUseAfterInsertions()` does not deal with that.
Notably, the external use can't happen to be both in the same block
and *after* the newly-cloned instruction, because of the fold preconditions.

To properly handle these cases, when the use is in the same block,
we should instead use `SSAUpdater::RewriteUse()`.
TBN, they do the same thing for PHI users.

Fixes https://bugs.llvm.org/show_bug.cgi?id=49510
Likely Fixes https://bugs.llvm.org/show_bug.cgi?id=49689
2021-03-23 17:37:28 +03:00
Sanjay Patel 1bf8f9e228 [SimplifyCFG] use profile metadata to refine merging branch conditions
2nd try (original: 27ae17a6b0) with fix/test for crash. We must make
sure that TTI is available before trying to use it because it is not
required (might be another bug).

Original commit message:

This is one step towards solving:
https://llvm.org/PR49336

In that example, we disregard the recommended usage of builtin_expect,
so an expensive (unpredictable) branch is folded into another branch
that is guarding it.
Here, we read the profile metadata to see if the 1st (predecessor)
condition is likely to cause execution to bypass the 2nd (successor)
condition before merging conditions by using logic ops.

Differential Revision: https://reviews.llvm.org/D98898
2021-03-23 10:19:37 -04:00
Luke Drummond 520f70e94d [NFC] clang-format llvm/lib/Transforms/Utils/CloneFunction.cpp
Differential Revision: https://reviews.llvm.org/D98957
2021-03-23 12:53:28 +00:00
Luke Drummond ab44ec1b22 [NFC] Minor refactor
- Give unwieldy repeated expression a name
- Use a ranged `for` basic block iterator

Reviewed by: nikic, dexonsmith
Differential Revisision: https://reviews.llvm.org/D98957
2021-03-23 12:53:28 +00:00
Luke Drummond 0448ddd169 [NFCI] cleanup CloneFunctionInto
Hoist early return for decl-only clones to before DIFinder
calculation.
Also fix an out of date assert message after invariants changed in
22a52dfddc.

Reviewed by: nikic, dexonsmith
Differential Revisision: https://reviews.llvm.org/D98957
2021-03-23 12:53:27 +00:00
Gulfem Savrun Yeniceri e3a6d70c68 Revert "[Passes] Add relative lookup table converter pass"
This reverts commit 78a65cd945 which
caused buildbot failures.
2021-03-23 00:43:16 +00:00
Juneyoung Lee 5c2e50b5d2 Reland "[SimplifyCFG] Update FoldBranchToCommonDest to be poison-safe"
This relands commit 99108c791d (D95026) which was
reverted by 8d5a981a13 because the underlying
problem (https://llvm.org/pr49495) is fixed.
2021-03-23 09:19:53 +09:00
Gulfem Savrun Yeniceri 78a65cd945 [Passes] Add relative lookup table converter pass
Lookup tables generate non PIC-friendly code, which requires dynamic relocation as described in:
https://bugs.llvm.org/show_bug.cgi?id=45244

This patch adds a new pass that converts lookup tables to relative lookup tables to make them PIC-friendly.

Differential Revision: https://reviews.llvm.org/D94355
2021-03-22 22:09:02 +00:00
Sanjay Patel 95f7f7c21b Revert "[SimplifyCFG] use profile metadata to refine merging branch conditions"
This reverts commit 27ae17a6b0.
There are bot failures that end with:
 #4 0x00007fff7ae3c9b8 CrashRecoverySignalHandler(int) CrashRecoveryContext.cpp:0:0
 #5 0x00007fff84e504d8 (linux-vdso64.so.1+0x4d8)
 #6 0x00007fff7c419a5c llvm::TargetTransformInfo::getPredictableBranchThreshold() const (/home/buildbots/ppc64le-clang-multistage-test/clang-ppc64le-multistage/stage1.install/bin/../lib/libLLVMAnalysis.so.13git+0x479a5c)

...but not sure how to trigger that yet.
2021-03-22 17:48:06 -04:00
Sanjay Patel 27ae17a6b0 [SimplifyCFG] use profile metadata to refine merging branch conditions
This is one step towards solving:
https://llvm.org/PR49336

In that example, we disregard the recommended usage of builtin_expect,
so an expensive (unpredictable) branch is folded into another branch
that is guarding it.
Here, we read the profile metadata to see if the 1st (predecessor)
condition is likely to cause execution to bypass the 2nd (successor)
condition before merging conditions by using logic ops.

Differential Revision: https://reviews.llvm.org/D98898
2021-03-22 16:49:21 -04:00
Bradley Smith 48f5a392cb [IR] Add vscale_range IR function attribute
This attribute represents the minimum and maximum values vscale can
take. For now this attribute is not hooked up to anything during
codegen, this will be added in the future when such codegen is
considered stable.

Additionally hook up the -msve-vector-bits=<x> clang option to emit this
attribute.

Differential Revision: https://reviews.llvm.org/D98030
2021-03-22 12:05:06 +00:00
Max Kazantsev 8fab9f824f [IndVars] Sharpen context in eliminateIVComparison
When eliminating comparisons, we can use common dominator of
all its users as context. This gives better results when ICMP is not
computed right before the branch that uses it.

Differential Revision: https://reviews.llvm.org/D98924
Reviewed By: lebedev.ri
2021-03-22 11:55:57 +07:00
Jeroen Dobbelaere 77080a1eb6 Revert of D49126 [PredicateInfo] Use custom mangling to support ssa_copy with unnamed types.
Now that intrinsic name mangling can cope with unnamed types, the custom name mangling in PredicateInfo (introduced by D49126) can be removed.
(See D91250, D48541)

Reviewed By: fhahn

Differential Revision: https://reviews.llvm.org/D91661
2021-03-20 11:37:09 +01:00
Max Kazantsev 8eefa07fcf [NFC] Move function up in code 2021-03-19 14:03:31 +07:00
Max Kazantsev 8bb952b57f [NFC] Factor out utility function for finding common dom of user set 2021-03-19 13:49:29 +07:00
Max Kazantsev 16370e02a7 [IndVars] Provide eliminateIVComparison with context
We can prove more predicates when we have a context when eliminating ICmp.
As first (and very obvious) approximation we can use the ICmp instruction itself,
though in the future we are going to use a common dominator of all its users.
Need some refactoring before that.

Observed ~0.5% negative compile time impact.

Differential Revision: https://reviews.llvm.org/D98697
Reviewed By: lebedev.ri
2021-03-19 12:28:22 +07:00
Max Kazantsev 26ec76add5 [NFC] One more use case for evaluatePredicate 2021-03-18 19:21:29 +07:00
Max Kazantsev 1067a13cc1 [NFC] Use evaluatePredicate in eliminateComparison
Just makes code simpler.
2021-03-18 19:21:29 +07:00
Stephen Tozer 3bfddc2593 Reapply "[DebugInfo] Handle multiple variable location operands in IR"
Fixed section of code that iterated through a SmallDenseMap and added
instructions in each iteration, causing non-deterministic code; replaced
SmallDenseMap with MapVector to prevent non-determinism.

This reverts commit 01ac6d1587.
2021-03-17 16:45:25 +00:00
Hans Wennborg 01ac6d1587 Revert "[DebugInfo] Handle multiple variable location operands in IR"
This caused non-deterministic compiler output; see comment on the
code review.

> This patch updates the various IR passes to correctly handle dbg.values with a
> DIArgList location. This patch does not actually allow DIArgLists to be produced
> by salvageDebugInfo, and it does not affect any pass after codegen-prepare.
> Other than that, it should cover every IR pass.
>
> Most of the changes simply extend code that operated on a single debug value to
> operate on the list of debug values in the style of any_of, all_of, for_each,
> etc. Instances of setOperand(0, ...) have been replaced with with
> replaceVariableLocationOp, which takes the value that is being replaced as an
> additional argument. In places where this value isn't readily available, we have
> to track the old value through to the point where it gets replaced.
>
> Differential Revision: https://reviews.llvm.org/D88232

This reverts commit df69c69427.
2021-03-17 13:36:48 +01:00
Juneyoung Lee edf634ebc2 [AssumeBundles] Add nonnull/align to op bundle if noundef exists
This is a patch to add nonnull and align to assume's operand bundle
only if noundef exists.
Since nonnull and align in fn attr have poison semantics, they should be
paired with noundef or noundef-implying attributes to be immediate UB.

Reviewed By: jdoerfert, Tyker

Differential Revision: https://reviews.llvm.org/D98228
2021-03-16 10:23:42 +09:00
Sanjay Patel bd197ed0a5 [SimplifyCFG] avoid sinking insts within an infinite-loop
The test is reduced from a C source example in:
https://llvm.org/PR49541

It's possible that the test could be reduced further or
the predicate generalized further, but it seems to require
a few ingredients (including the "late" SimplifyCFG options
on the RUN line) to fall into the infinite-loop trap.
2021-03-12 08:04:57 -05:00
Wenlei He 051f2c144e [SamplePGO] Skip inlinee profile scaling for sample loader inlining
For CGSCC inline, we need to scale down a function's branch weights and entry counts when thee it's inlined at a callsite. This is done through updateCallProfile. Additionally, we also scale the weigths for the inlined clone based on call site count in updateCallerBFI. Neither is needed for inlining during sample profile loader as it's using context profile that is separated from inlinee's own profile. This change skip the inlinee profile scaling for sample loader inlining.

Differential Revision: https://reviews.llvm.org/D98187
2021-03-11 10:18:26 -08:00