Commit Graph

752 Commits

Author SHA1 Message Date
Roman Lebedev 1f9b591ee6
[SimplifyCFG] TryToSimplifyUncondBranchFromEmptyBlock(): switch to non-permissive DomTree updates
... which requires not deleting edges that were just deleted already,
    by not processing the same predecessor more than once.
2021-01-08 02:15:25 +03:00
Roman Lebedev b3822728fa
[SimplifyCFG] ConstantFoldTerminator(): switch to non-permissive DomTree updates in `indirectbr` handling
... which requires not deleting edges that were just deleted already.
2021-01-08 02:15:25 +03:00
Roman Lebedev 36593a30a4
[SimplifyCFG] ConstantFoldTerminator(): switch to non-permissive DomTree updates in `SwitchInst` handling
... which requires not deleting edges that will still be present.
2021-01-08 02:15:24 +03:00
Roman Lebedev 16ab8e5f6d
[SimplifyCFG] ConstantFoldTerminator(): handle matching destinations of condbr earlier
We need to handle this case before dealing with the case of constant
branch condition, because if the destinations match, latter fold
would try to remove the DomTree edge that would still be present.

This allows to make that particular DomTree update non-permissive
2021-01-08 02:15:24 +03:00
Francesco Petrogalli dfd3384fee [InstCombine] Update valueCoversEntireFragment to use TypeSize
* Update valueCoversEntireFragment to use TypeSize.
* Add a regression test.
* Assertions have been added to protect untested codepaths.

Reviewed By: sdesmalen

Differential Revision: https://reviews.llvm.org/D91806
2021-01-06 17:14:59 +00:00
Kazu Hirata 16d20e2554 [Transforms/Utils] Construct SmallVector with iterator ranges (NFC) 2020-12-29 19:23:23 -08:00
Kazu Hirata 46bea9b297 [Local] Remove unused function RemovePredecessorAndSimplify (NFC)
The last use of the function was removed on Sep 29, 2010 in commit
99c985c37d.
2020-12-25 09:35:20 -08:00
Fangrui Song b5ad32ef5c Migrate deprecated DebugLoc::get to DILocation::get
This migrates all LLVM (except Kaleidoscope and
CodeGen/StackProtector.cpp) DebugLoc::get to DILocation::get.

The CodeGen/StackProtector.cpp usage may have a nullptr Scope
and can trigger an assertion failure, so I don't migrate it.

Reviewed By: #debug-info, dblaikie

Differential Revision: https://reviews.llvm.org/D93087
2020-12-11 12:45:22 -08:00
Kazu Hirata 43c0e4f665 [Transforms] Use llvm::is_contained (NFC) 2020-11-18 20:42:22 -08:00
Arthur Eubanks 5c31b8b94f Revert "Use uint64_t for branch weights instead of uint32_t"
This reverts commit 10f2a0d662.

More uint64_t overflows.
2020-10-31 00:25:32 -07:00
Arthur Eubanks 10f2a0d662 Use uint64_t for branch weights instead of uint32_t
CallInst::updateProfWeight() creates branch_weights with i64 instead of i32.
To be more consistent everywhere and remove lots of casts from uint64_t
to uint32_t, use i64 for branch_weights.

Reviewed By: davidxl

Differential Revision: https://reviews.llvm.org/D88609
2020-10-30 10:03:46 -07:00
Simon Pilgrim bce770ffa6 Revert rG0905bd5c2fa42bd4c "[InstCombine] collectBitParts - add trunc support."
This reverts commit 0905bd5c2f.

Causing failures in multistage buildbots that I need to investigate
2020-10-27 13:43:54 +00:00
Nico Weber 2a4e704c92 Revert "Use uint64_t for branch weights instead of uint32_t"
This reverts commit e5766f25c6.
Makes clang assert when building Chromium, see https://crbug.com/1142813
for a repro.
2020-10-27 09:26:21 -04:00
Simon Pilgrim 0905bd5c2f [InstCombine] collectBitParts - add trunc support.
This should allow us to remove the rather limited matchOrConcat fold and just use recognizeBSwapOrBitReverseIdiom.
2020-10-27 13:14:54 +00:00
Arthur Eubanks e5766f25c6 Use uint64_t for branch weights instead of uint32_t
CallInst::updateProfWeight() creates branch_weights with i64 instead of i32.
To be more consistent everywhere and remove lots of casts from uint64_t
to uint32_t, use i64 for branch_weights.

Reviewed By: davidxl

Differential Revision: https://reviews.llvm.org/D88609
2020-10-26 20:24:04 -07:00
Simon Pilgrim 532f3bec3e [InstCombine] collectBitParts - add bitreverse intrinsic support. 2020-10-26 14:36:36 +00:00
Artur Pilipenko 6ec2c5e402 GC-parseable element atomic memcpy/memmove
This change introduces a GC parseable lowering for element atomic
memcpy/memmove intrinsics. This way runtime can provide an
implementation which can take a safepoint during copy operation.

See "GC-parseable element atomic memcpy/memmove" thread on llvm-dev
for the background and details:
https://groups.google.com/g/llvm-dev/c/NnENHzmX-b8/m/3PyN8Y2pCAAJ

Differential Revision: https://reviews.llvm.org/D88861
2020-10-23 14:06:09 -07:00
Simon Pilgrim aacfe2be53 [InstCombine] recognizeBSwapOrBitReverseIdiom - add vector support
Add basic vector handling to recognizeBSwapOrBitReverseIdiom/collectBitParts - this works at the element level, all vector element operations must match (splat constants etc.) and there is no cross-element support (insert/extract/shuffle etc.).
2020-10-03 16:26:46 +01:00
Simon Pilgrim 347fd9955a [InstCombine] recognizeBSwapOrBitReverseIdiom - use generic CreateIntegerCast
Try to appease buildbots breakages due to D88578
2020-10-03 15:29:22 +01:00
Simon Pilgrim 3aa93f690b [InstCombine] recognizeBSwapOrBitReverseIdiom - support for 'partial' bswap patterns (PR47191) (Reapplied)
If we're bswap'ing some bytes and zero'ing the remainder we can perform this as a bswap+mask which helps us match 'partial' bswaps as a first step towards folding into a more complex bswap pattern.

Reapplied with early-out if recognizeBSwapOrBitReverseIdiom collects a source wider than the result type.

Differential Revision: https://reviews.llvm.org/D88578
2020-10-03 14:52:42 +01:00
Simon Pilgrim 0364721e3e Revert rG3d14a1e982ad27 - "[InstCombine] recognizeBSwapOrBitReverseIdiom - support for 'partial' bswap patterns (PR47191)"
This reverts commit 3d14a1e982.

This is breaking on some 2stage clang buildbots
2020-10-02 18:17:14 +01:00
Simon Pilgrim 3d14a1e982 [InstCombine] recognizeBSwapOrBitReverseIdiom - support for 'partial' bswap patterns (PR47191)
If we're bswap'ing some bytes and zero'ing the remainder we can perform this as a bswap+mask which helps us match 'partial' bswaps as a first step towards folding into a more complex bswap pattern.

Differential Revision: https://reviews.llvm.org/D88578
2020-10-02 17:25:12 +01:00
Simon Pilgrim 29ac9fae54 [InstCombine] collectBitParts - convert to use PatterMatch matchers and avoid IntegerType casts.
Make sure we're using getScalarSizeInBits instead of cast<IntegerType> to get Type bit widths.

This is preliminary cleanup before we can start adding vector support to the bswap/bitreverse (element level) matching.
2020-10-01 16:44:14 +01:00
Simon Pilgrim bc730b5e43 [InstCombine] collectBitParts - use APInt directly to check for out of range bit shifts. NFCI. 2020-10-01 12:50:36 +01:00
Simon Pilgrim c722b32596 [InstCombine] recognizeBSwapOrBitReverseIdiom - merge the regular/trunc+zext paths. NFCI.
There doesn't seem to be any good reason for having a separate path for when we bswap/bitreverse at a smaller size than the destination size - so merge these to make the instruction generation a lot clearer.
2020-09-30 14:54:04 +01:00
Simon Pilgrim d5545a8993 [InstCombine] recognizeBSwapOrBitReverseIdiom - remove unnecessary cast. NFCI. 2020-09-30 14:44:15 +01:00
Simon Pilgrim 621c6c8962 [InstCombine] recognizeBSwapOrBitReverseIdiom - cleanup bswap/bitreverse detection loop. NFCI.
Early out if both pattern matches have failed (or we don't want them). Fix case of bit index iterator (and avoid Wshadow issue).
2020-09-30 14:19:18 +01:00
Simon Pilgrim 413b4998bd [InstCombine] recognizeBSwapOrBitReverseIdiom - use ArrayRef::back() helper. NFCI.
Post-commit feedback on D88316
2020-09-30 13:39:18 +01:00
Simon Pilgrim 05290eead3 InstCombine] collectBitParts - cleanup variable names. NFCI.
Fix a number of WShadow warnings (I was used as the instruction and index......) and fix cases to match style.

Also, replaced the Bit APInt mask check in AND instructions with a direct APInt[] bit check.
2020-09-30 13:25:32 +01:00
Simon Pilgrim af47d40b9c [InstCombine] recognizeBSwapOrBitReverseIdiom - recognise zext(bswap(trunc(x))) patterns (PR39793)
PR39793 demonstrated an issue where we fail to recognize 'partial' bswap patterns of the lower bytes of an integer source.

In fact, most of this is already in place collectBitParts suitably tags zero bits, so we just need to correctly handle this case by finding the zero'd upper bits and reducing the bswap pattern just to the active demanded bits.

Differential Revision: https://reviews.llvm.org/D88316
2020-09-30 12:07:19 +01:00
Simon Pilgrim ec3f24d453 [InstCombine] recognizeBSwapOrBitReverseIdiom - assert for correct bit providence indices. NFCI.
As suggested by @spatel on D88316
2020-09-30 11:16:33 +01:00
Simon Pilgrim 2a0ca17f66 [InstCombine] collectBitParts - add fshl/fshr handling
Pulled from D87452, this is a fixed version of the collectBitParts fshl/fshr handling which as @nikic noticed wasn't checking for different providers or had correct bit ordering (which was hid by only testing shift amounts of bitwidth/2).

Differential Revision: https://reviews.llvm.org/D88292
2020-09-25 20:34:59 +01:00
Nikita Popov f4e5541809 [Local] Clean up enforceKnownAlignment() (NFC)
I want to export this function, and the current API was a bit
weird: It took an additional Alignment argument that didn't really
have anything to do with what the function does. Drop it, and
perform a max at the callsite.

Also rename it to tryEnforceAlignment().
2020-09-19 22:29:40 +02:00
Roman Lebedev aadf55d1ce
[NFC] EliminateDuplicatePHINodes(): small-size optimization: if there are <= 32 PHI's, O(n^2) algo is faster (geomean -0.08%)
This is functionally equivalent to the old implementation.

As per https://llvm-compile-time-tracker.com/compare.php?from=5f4e9bf6416e45eba483a4e5e263749989fdb3b3&to=4739e6e4eb54d3736e6457249c0919b30f6c855a&stat=instructions
this is a clear geomean compile-time regression-free win with overall geomean of `-0.08%`

32 PHI's appears to be the sweet spot; both the 16 and 64 performed worse:
https://llvm-compile-time-tracker.com/compare.php?from=5f4e9bf6416e45eba483a4e5e263749989fdb3b3&to=c4efe1fbbfdf0305ac26cd19eacb0c7774cdf60e&stat=instructions
https://llvm-compile-time-tracker.com/compare.php?from=5f4e9bf6416e45eba483a4e5e263749989fdb3b3&to=e4989d1c67010d3339d1a40ff5286a31f10cfe82&stat=instructions

If we have more PHI's than that, we fall-back to the original DenseSet-based implementation,
so the not-so-fast cases will still be handled.

However compile-time isn't the main motivation here.
I can name at least 3 limitations of this CSE:
1. Assumes that all PHI nodes have incoming basic blocks in the same order (can be fixed while keeping the DenseMap)
2. Does not special-handle `undef` incoming values (i don't see how we can do this with hashing)
3. Does not special-handle backedge incoming values (maybe can be fixed by hashing backedge as some magical value)

Reviewed By: efriedma

Differential Revision: https://reviews.llvm.org/D87408
2020-09-17 11:29:03 +03:00
Simon Pilgrim 4ff4708d39 collectBitParts - use const references. NFCI.
Fixes clang-tidy warnings first noticed on D87452.
2020-09-14 18:23:00 +01:00
serge-sans-paille 3a6f3fc160 Fix return status of SimplifyCFG
When a switch case is folded into default's case, that's an IR change that
should be reported, update ConstantFoldTerminator accordingly.

Differential Revision: https://reviews.llvm.org/D87142
2020-09-05 07:54:15 +02:00
Roman Lebedev 1dcb936cf6
[NFC][Local] EliminateDuplicatePHINodes(): add STATISTIC() 2020-08-29 22:03:18 +03:00
Roman Lebedev 961483a5ea
[NFCI][Local] Rewrite EliminateDuplicatePHINodes to optionally check hashing invariants
EarlyCSE has a mode to verify the invariant that hash equality equals
key equality, but EliminateDuplicatePHINodes() doesn't.

I've verified that this would have caught the stage2-stage3 mismatches
5ec2b757cc revert has fixed,
that were introduced last time in 3e69871ab5.
2020-08-29 22:03:10 +03:00
Roman Lebedev 5ec2b757cc
[Instruction] Speculatively undo isIdenticalToWhenDefined() PHI handling changes
The stage2-stage3 differences persist even without instcombine-based
PHI CSE, so this is the only possible reason.
2020-08-29 19:38:57 +03:00
David Stenberg e8ebebb0bd [InstCombine] Fix incorrect Modified status
When removing instructions from unreachable blocks, and only debug info
intrinsics were removed, InstCombine could incorrectly return a false
Modified status.

This is fixed by making removeAllNonTerminatorAndEHPadInstructions()
also return how many debug info intrinsics that were removed, and take
that into account.

This was caught using the check introduced by D80916.

Reviewed By: majnemer

Differential Revision: https://reviews.llvm.org/D85839
2020-08-13 15:10:41 +02:00
Vitaly Buka 61cab352e3 [NFC] Move findAllocaForValue into ValueTracking.h
Differential Revision: https://reviews.llvm.org/D84616
2020-07-30 18:22:59 -07:00
Tim Northover 37b96d51d0 CodeGenPrep: remove AssertingVH references before deleting dead instructions.
CodeGenPrepare keeps fairly close track of various instructions it's
seen, particularly GEPs, in maps and vectors. However, sometimes those
instructions become dead and get removed while it's still executing.
This triggers AssertingVH references to them in an asserts build and
could lead to miscompiles in a release build (I've only seen a later
segfault though).

So this patch adds a callback to
RecursivelyDeleteTriviallyDeadInstructions which can make sure the
instruction about to be deleted is removed from CodeGenPrepare's data
structures.
2020-07-15 15:19:21 +01:00
Yevgeny Rouban 6429471e8b [IR] Convert profile metadata in createCallMatchingInvoke()
When an invoke instruction is converted to a call its
profile metadata is dropped because it has incompatible
format (see commit 16ad6eeb94).
This patch adds an attempt to convert profile data to
format of the call instruction. This used to work well
before the commit dcfa78a4cc.

Reviewers: reames
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D82071
2020-06-20 12:10:31 +07:00
Hans Wennborg 16ad6eeb94 [IR] Don't copy profile metadata in createCallMatchingInvoke()
The invoke instruction can have profile metadata with branch_weights,
which does not make sense for a call instruction and will be
rejected by the verifier.

Differential revision: https://reviews.llvm.org/D81996
2020-06-17 11:18:23 +02:00
Jay Foad 6fdd5a28b7 Revert "[IR] Clean up dead instructions after simplifying a conditional branch"
This reverts commit 69bdfb075b.

Reverting to investigate https://bugs.llvm.org/show_bug.cgi?id=46343
2020-06-16 10:32:15 +01:00
Jay Foad 69bdfb075b [IR] Clean up dead instructions after simplifying a conditional branch
Change BasicBlock::removePredecessor to optionally return a vector of
instructions which might be dead. Use this in ConstantFoldTerminator to
delete them if they are dead.

Reapply with a bug fix: don't drop the "!KeepOneInputPHIs" argument when
removePredecessor calls PHINode::removeIncomingValue.

Differential Revision: https://reviews.llvm.org/D80206
2020-06-11 14:53:01 +01:00
Jay Foad f45c65aa41 Revert "[IR] Clean up dead instructions after simplifying a conditional branch"
This reverts commit 4494e45316.

It caused problems for sanitizer buildbots.
2020-06-11 14:22:16 +01:00
Jay Foad 4494e45316 [IR] Clean up dead instructions after simplifying a conditional branch
Change BasicBlock::removePredecessor to optionally return a vector of
instructions which might be dead. Use this in ConstantFoldTerminator to
delete them if they are dead.

Differential Revision: https://reviews.llvm.org/D80206
2020-06-11 13:28:10 +01:00
Chris Jackson 4707bc2177 [DebugInfo] Refactor SalvageDebugInfo and SalvageDebugInfoForDbgValues
- Simplify the salvaging interface and the algorithm in InstCombine

Reviewers: vsk, aprantl, Orlando, jmorse, TWeaver

Reviewed by: Orlando

Differential Revision: https://reviews.llvm.org/D79863
2020-06-11 11:13:46 +01:00
Chris Jackson c6c65164af [DebugInfo] Reduce SalvageDebugInfo() functions
- Now all SalvageDebugInfo() calls will mark undef if the salvage
  attempt fails.

 Reviewed by: vsk, Orlando

 Differential Revision: https://reviews.llvm.org/D78369
2020-06-08 19:28:18 +01:00
Benjamin Kramer 3badd17b69 SmallPtrSet::find -> SmallPtrSet::count
The latter is more readable and more efficient. While there clean up
some double lookups. NFCI.
2020-06-07 22:38:08 +02:00
Ehud Katz c710bb44a6 [Local] Prevent `invertCondition` from creating a redundant instruction
Prevent `invertCondition` from creating the inversion instruction, in
case the given value is an argument which has already been inverted.
Note that this approach has already been taken in case the given value
is an instruction (and not an argument).

Differential Revision: https://reviews.llvm.org/D80399
2020-05-29 21:08:22 +03:00
Vedant Kumar 623b254244 [Local] Do not ignore zexts in salvageDebugInfo, PR45923
Summary:
When salvaging a dead zext instruction, append a convert operation to
the DIExpressions of the debug uses of the instruction, to prevent the
salvaged value from being sign-extended.

I confirmed that lldb prints out the correct unsigned result for "f" in
the example from PR45923 with this changed applied.

rdar://63246143

Reviewers: aprantl, jmorse, chrisjackson, davide

Subscribers: hiraditya, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D80034
2020-05-18 09:52:02 -07:00
Eli Friedman 4f04db4b54 AllocaInst should store Align instead of MaybeAlign.
Along the lines of D77454 and D79968.  Unlike loads and stores, the
default alignment is getPrefTypeAlign, to match the existing handling in
various places, including SelectionDAG and InstCombine.

Differential Revision: https://reviews.llvm.org/D80044
2020-05-16 14:53:16 -07:00
zoecarver f65f566aeb Re-commit: Mark values as trivially dead when their only use is a start or end lifetime intrinsic.
Summary:
If the only use of a value is a start or end lifetime intrinsic then mark the intrinsic as trivially dead. This should allow for that value to then be removed as well.

Currently, this only works for allocas, globals, and arguments.

Subscribers: hiraditya, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D79355
2020-05-08 12:24:10 -07:00
zoecarver 1998e796e9 Revert "Mark values as trivially dead when their only use is a start or end lifetime intrinsic."
This reverts commit 95aa28cc8f.
2020-05-06 11:07:22 -07:00
zoecarver 95aa28cc8f Mark values as trivially dead when their only use is a start or end lifetime intrinsic.
Summary:
If the only use of a value is a start or end lifetime intrinsic then mark the intrinsic as trivially dead. This should allow for that value to then be removed as well.

Currently, this only works for allocas, globals, and arguments.

Subscribers: hiraditya, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D79355
2020-05-06 10:58:08 -07:00
Craig Topper a58b62b4a2 [IR] Replace all uses of CallBase::getCalledValue() with getCalledOperand().
This method has been commented as deprecated for a while. Remove
it and replace all uses with the equivalent getCalledOperand().

I also made a few cleanups in here. For example, to removes use
of getElementType on a pointer when we could just use getFunctionType
from the call.

Differential Revision: https://reviews.llvm.org/D78882
2020-04-27 22:17:03 -07:00
Craig Topper 81c5e83f7d [CallSite removal][Transform] Replace CallSite with CallBase in Utils. NFC
Differential Revision: https://reviews.llvm.org/D78780
2020-04-23 20:49:33 -07:00
Simon Pilgrim d9af50efbc [Transforms] getOrEnforceKnownAlignment - fix MSVC result of 32-bit shift implicitly converted to 64 bits warning. NFCI
We don't overflow here so we can use a U64 shift directly.
2020-04-21 18:32:12 +01:00
Craig Topper 68b2e507e4 [Local] Update getOrEnforceKnownAlignment/getKnownAlignment to use Align/MaybeAlign.
Differential Revision: https://reviews.llvm.org/D78443
2020-04-20 21:31:44 -07:00
Craig Topper fcc9d70260 Revert "[Local] Update getOrEnforceKnownAlignment/getKnownAlignment to use Align/MaybeAlign."
This is breaking the clang build.

This reverts commit 897409fb56.
2020-04-20 13:25:06 -07:00
Craig Topper 897409fb56 [Local] Update getOrEnforceKnownAlignment/getKnownAlignment to use Align/MaybeAlign.
Differential Revision: https://reviews.llvm.org/D78443
2020-04-20 13:08:05 -07:00
Craig Topper 7fde990694 Recommit "[Local] Simplify the alignment limits in getOrEnforceKnownAlignment. NFCI"
With a tweak to avoid a linker error for passing
MaxAlignmentExponent by reference to std::min.
2020-04-18 13:51:57 -07:00
Craig Topper 44d63b7528 Revert "[Local] Simplify the alignment limits in getOrEnforceKnownAlignment. NFCI"
This reverts commit e00cfe254d.

Seems to be causing a linker error on the build bots.
2020-04-18 13:23:29 -07:00
Craig Topper e00cfe254d [Local] Simplify the alignment limits in getOrEnforceKnownAlignment. NFCI
We previously clamped the trailing zero count to 31 bits. And
then clamped the final alignment to MaximumAlignment which is
1 << 29.

This patch simplifies this to just clamp the trailing zero to
29 using MaxAlignmentExponent.

I was looking into changing this function to use Align/MaybeAlign
and noticed this.

Differential Revision: https://reviews.llvm.org/D78418
2020-04-18 12:52:47 -07:00
Craig Topper 8e1408695c [CallSite removal][TargetLibraryInfo] Replace ImmutableCallSite with CallBase in one of the getLibFunc signatures. NFC
Differential Revision: https://reviews.llvm.org/D78083
2020-04-15 22:43:41 -07:00
Eli Friedman 3f13ee8a00 [NFC] Modernize misc. uses of Align/MaybeAlign APIs.
Use the current getAlign() APIs where it makes sense, and use Align
instead of MaybeAlign when we know the value is non-zero.
2020-04-06 17:53:04 -07:00
Tyker c00cb76274 [NFC] Split Knowledge retention and place it more appropriatly
Summary:
Splitting Knowledge retention into Queries in Analysis and Builder into Transform/Utils
allows Queries and Transform/Utils to use Analysis.

Reviewers: jdoerfert, sstefan1

Reviewed By: jdoerfert

Subscribers: mgorny, hiraditya, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D77171
2020-04-02 15:01:41 +02:00
Sameer Sahasrabuddhe 3cbbded68c Introduce unify-loop-exits pass.
For each natural loop with multiple exit blocks, this pass creates a
new block N such that all exiting blocks now branch to N, and then
control flow is redistributed to all the original exit blocks.

The bulk of the tranformation is a new function introduced in
BasicBlockUtils that an redirect control flow from a set of incoming
blocks to a set of outgoing blocks via a common "hub".

This is a useful workaround for a limitation in the structurizer which
incorrectly orders blocks when processing a nest of loops. This pass
bypasses that issue by ensuring that each natural loop is recognized
as a separate region. Since the structurizer is a region pass, it no
longer sees a nest of loops in a single region, and instead processes
each "level" in the nesting as a separate region.

The AMDGPU backend provides a new option to enable this pass before
the structurizer, which may eventually be enabled by default.

Reviewers: madhur13490, arsenm, nhaehnle

Reviewed By: nhaehnle

Differential Revision: https://reviews.llvm.org/D75865
2020-03-30 13:23:56 -04:00
Matt Arsenault 43d98a0ecf Allow replacing intrinsic operands with variables
Since intrinsics can now specify when an argument is required to be
constant, it is now OK to replace arguments with variables if they
aren't. This means intrinsics must now be accurately marked with
immarg.
2020-03-23 15:51:57 -04:00
Tyker e8ac825f5b [AssumeBundles] Detection of Empty bundles
Summary: Prevent InstCombine from removing llvm.assume for which the arguement is true when they have operand bundles with usefull information.

Reviewers: jdoerfert, nikic, lebedev.ri

Reviewed By: jdoerfert

Subscribers: hiraditya, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D76147
2020-03-17 15:50:15 +01:00
Brian Gesiak aa85b437a9 [Coroutines] Use dbg.declare for frame variables
Summary:
https://gist.github.com/modocache/ed7c62f6e570766c0f39b35dad675c2f
is an example of a small C++ program that uses C++20 coroutines that
is difficult to debug, due to the loss of debug info for variables that
"spill" across coroutine suspension boundaries. This patch addresses
that issue by inserting 'llvm.dbg.declare' intrinsics that point the
debugger to the variables' location at an offset to the coroutine frame.

With this patch, I confirmed that running the 'frame variable' commands in
https://gist.github.com/modocache/ed7c62f6e570766c0f39b35dad675c2f at
the specified breakpoints results in the correct values being printed
for coroutine frame variables 'i' and 'j' when using an lldb built from
trunk, as well as with gdb 8.3 (lldb 9.0.1, however, could not print the
values). The added test case also verifies this improved behavior.

The existing coro-debug.ll test case is also modified to reflect the
locations at which Clang actually places calls to 'dbg.declare', and
additional checks are added to ensure this patch works as intended in that
example as well.

Reviewers: vsk, jmorse, GorNishanov, lewissbaker, wenlei

Subscribers: EricWF, aprantl, hiraditya, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D75338
2020-03-03 17:13:46 -05:00
Alok Kumar Sharma 6f029dadf6 [DebugInfo] Avoid generating duplicate llvm.dbg.value
Summary:
This is to avoid generating duplicate llvm.dbg.value instrinsic if it already exists after the Instruction.

Before inserting llvm.dbg.value instruction, LLVM checks if the same instruction is already present before the instruction to avoid duplicates.
Currently it misses to check if it already exists after the instruction.
flang generates IR like this.

%4 = load i32, i32* %i1_311, align 4, !dbg !42
call void @llvm.dbg.value(metadata i32 %4, metadata !35, metadata !DIExpression()), !dbg !33
When this IR is processed in llvm, it ends up inserting duplicates.
%4 = load i32, i32* %i1_311, align 4, !dbg !42
call void @llvm.dbg.value(metadata i32 %4, metadata !35, metadata !DIExpression()), !dbg !33
call void @llvm.dbg.value(metadata i32 %4, metadata !35, metadata !DIExpression()), !dbg !33
We have now updated LdStHasDebugValue to include the cases when instruction is already
followed by same dbg.value instruction we intend to insert.

Now,

Definition and usage of function LdStHasDebugValue are deleted.
RemoveRedundantDbgInstrs is called for the cleanup of duplicate dbg.value's

Testing:
Added unit test for validation
check-llvm
check-debuginfo (the debug info integration tests)

Reviewers: aprantl, probinson, dblaikie, jmorse, jini.susan.george
SouraVX, awpandey, dstenb, vsk

Reviewed By: aprantl, jmorse, dstenb, vsk

Differential Revision: https://reviews.llvm.org/D74030
2020-03-03 09:56:45 +05:30
Vedant Kumar 8e77b33b3c [Local] Do not move around dbg.declares during replaceDbgDeclare
replaceDbgDeclare is used to update the descriptions of stack variables
when they are moved (e.g. by ASan or SafeStack). A side effect of
replaceDbgDeclare is that it moves dbg.declares around in the
instruction stream (typically by hoisting them into the entry block).
This behavior was introduced in llvm/r227544 to fix an assertion failure
(llvm.org/PR22386), but no longer appears to be necessary.

Hoisting a dbg.declare generally does not create problems. Usually,
dbg.declare either describes an argument or an alloca in the entry
block, and backends have special handling to emit locations for these.
In optimized builds, LowerDbgDeclare places dbg.values in the right
spots regardless of where the dbg.declare is. And no one uses
replaceDbgDeclare to handle things like VLAs.

However, there doesn't seem to be a positive case for moving
dbg.declares around anymore, and this reordering can get in the way of
understanding other bugs. I propose getting rid of it.

Testing: stage2 RelWithDebInfo sanitized build, check-llvm

rdar://59397340

Differential Revision: https://reviews.llvm.org/D74517
2020-02-13 14:35:02 -08:00
stozer 9bda7ab835 Re-revert: Recover debug intrinsics when killing duplicated/empty blocks
This reverts commit 61b35e4111.

This commit causes a timeout in chromium builds; likely to have a
similar cause to the previous timeout issue caused by this commit (see
6ded69f294 for more details). It is possible that there is no way to
fix this bug that will not cause this issue; further investigations as
to the efficiency of handling large amounts of debug info will be
necessary.
2020-02-13 11:48:19 +00:00
stozer 61b35e4111 Re-reapply: Recover debug intrinsics when killing duplicated/empty blocks
This reverts commit 636c93ed11.

The original patch caused build failures on TSan buildbots. Commit 6ded69f294
fixes this issue by reducing the rate at which empty debug intrinsics
propagate, reducing the memory footprint and preventing a fatal spike.
2020-02-12 14:36:30 +00:00
Alina Sbirlea 1d09174290 [LoopStrengthReduce] Reuse utility method to clean dead instructions. [NFCI]
Create a utility wrapper for the RecursivelyDeleteTriviallyDeadInstructions utility
method, which sets to nullptr the instructions that are not trivially
dead. Use the new method in LoopStrengthReduce.
Alternative: add a bool to the same method; this option adds a marginal
amount of overhead to the other callers, and the method needs to be
updated to return a bool status when it removes/doesn't remove
instructions.
2020-01-23 16:27:32 -08:00
Alina Sbirlea 9e66c4ec12 [Utils] Use WeakTrackingVH in vector used as scratch storage.
The utility method RecursivelyDeleteTriviallyDeadInstructions receives
as input a vector of Instructions, where all inputs are valid
instructions. This same vector is used as a scratch storage (per the
header comment) to recursively delete instructions. If an instruction is
added as an operand of multiple other instructions, it may be added twice,
then deleted once, then the second reference in the vector is invalid.
Switch to using a Vector<WeakTrackingVH>.
This change facilitates a clean-up in LoopStrengthReduction.
2020-01-23 16:04:57 -08:00
Alina Sbirlea a0f627d584 [IndVarSimplify] Fix for MemorySSA preserve. 2020-01-23 11:06:16 -08:00
stozer 89d19d60ad Reapply: [DebugInfo] Correctly handle salvaged casts and split fragments at ISel
This reverts commit 1f3dd83cc1, reapplying
commit bb1b0bc4e5.

The original commit failed on some builds seemingly due to the use of a
bracketed constructor with an std::array, i.e. `std::array<> arr({...})`.
2019-12-18 16:26:42 +00:00
stozer 1f3dd83cc1 Revert "[DebugInfo] Correctly handle salvaged casts and split fragments at ISel"
Reverted due to build failure on windows bots.

This reverts commit bb1b0bc4e5.
2019-12-18 11:46:10 +00:00
stozer bb1b0bc4e5 [DebugInfo] Correctly handle salvaged casts and split fragments at ISel
Previously, LLVM had no functional way of performing casts inside of a
DIExpression(), which made salvaging cast instructions other than Noop
casts impossible. This patch enables the salvaging of casts by using the
DW_OP_LLVM_convert operator for SExt and Trunc instructions.

There is another issue which is exposed by this fix, in which fragment
DIExpressions (which are preserved more readily by this patch) for
values that must be split across registers in ISel trigger an assertion,
as the 'split' fragments extend beyond the bounds of the fragment
DIExpression causing an error. This patch also fixes this issue by
checking the fragment status of DIExpressions which are to be split, and
dropping fragments that are invalid.
2019-12-18 11:09:18 +00:00
Nicola Zaghen 97572775d2 Reland [DataLayout] Fix occurrences that size and range of pointers are assumed to be the same.
GEP index size can be specified in the DataLayout, introduced in D42123. However, there were still places
in which getIndexSizeInBits was used interchangeably with getPointerSizeInBits. This notably caused issues
with Instcombine's visitPtrToInt; but the unit tests was incorrect, so this remained undiscovered.

This fixes the buildbot failures.

Differential Revision: https://reviews.llvm.org/D68328

Patch by Joseph Faulls!
2019-12-13 14:30:21 +00:00
Nicola Zaghen f798eb21ec Temporarily Revert "[DataLayout] Fix occurrences that size and range of pointers are assumed to be the same."
This reverts commit 5f6208778f.

This caused failures in Transforms/PhaseOrdering/scev-custom-dl.ll
const: Assertion `getBitWidth() == CR.getBitWidth() && "ConstantRange types don't agree!"' failed.
2019-12-12 10:29:54 +00:00
Nicola Zaghen 5f6208778f [DataLayout] Fix occurrences that size and range of pointers are assumed to be the same.
GEP index size can be specified in the DataLayout, introduced in D42123. However, there were still places
in which getIndexSizeInBits was used interchangeably with getPointerSizeInBits. This notably caused issues
with Instcombine's visitPtrToInt; but the unit tests was incorrect, so this remained undiscovered.

Differential Revision: https://reviews.llvm.org/D68328

Patch by Joseph Faulls!
2019-12-12 10:07:01 +00:00
Vlad Tsyrklevich 636c93ed11 Revert "Reapply: [DebugInfo] Recover debug intrinsics when killing duplicated/empty..."
This reverts commit f2ba93971c, it was
causing build timeouts on sanitizer-x86_64-linux-autoconf such as
http://lab.llvm.org:8011/builders/sanitizer-x86_64-linux-autoconf/builds/44917
2019-12-10 16:03:17 -08:00
stozer f2ba93971c Reapply: [DebugInfo] Recover debug intrinsics when killing duplicated/empty...
basic blocks

Originally applied in 72ce759928.

Fixed a build failure caused by incorrect use of cast instead of
dyn_cast.

This reverts commit 8b0780f795.
2019-12-10 13:33:32 +00:00
Evgenii Stepanov 6f89cbc429 LowerDbgDeclare: look through bitcasts.
Summary:
Emit a value debug intrinsic (with OP_deref) when an alloca address is
passed to a function call after going through a bitcast.

This generates an FP or SP-relative location for the local variable in
the following case:
  int x;
  use((void *)&x;

Reviewers: aprantl, vsk, pcc

Subscribers: hiraditya, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D70752
2019-12-05 11:19:07 -08:00
Tozer 8b0780f795 Revert "[DebugInfo] Recover debug intrinsics when killing duplicated/empty basic blocks"
This reverts commit 72ce759928.

Reverted due to build failure.
2019-12-04 18:47:08 +00:00
stozer 72ce759928 [DebugInfo] Recover debug intrinsics when killing duplicated/empty basic blocks
When basic blocks are killed, either due to being empty or to being an if.then
or if.else block whose complement contains identical instructions, some of the
debug intrinsics in that block are lost. This patch sinks those intrinsics
into the single successor block, setting them Undef if necessary to
prevent debug info from falling out-of-date.

Differential Revision: https://reviews.llvm.org/D70318
2019-12-04 16:01:49 +00:00
OCHyams 2de23c8364 [DebugInfo@O2][Utils] Undef instead of delete dbg.values in helper func
Summary:
Related bug: https://bugs.llvm.org/show_bug.cgi?id=40648

Static helper function rewriteDebugUsers in Local.cpp deletes dbg.value
intrinsics when it cannot move or rewrite them, or salvage the deleted
instruction's value. It should instead undef them in this case.

This patch fixes that and I've added a test which covers the failing test
case in bz40648. I've updated the unit test Local.ReplaceAllDbgUsesWith
to check for this behaviour (and fixed a typo in the test which would
cause the old test to always pass).

Reviewers: aprantl, vsk, djtodoro, probinson

Reviewed By: vsk

Subscribers: hiraditya, llvm-commits

Tags: #debug-info, #llvm

Differential Revision: https://reviews.llvm.org/D70604
2019-11-25 10:55:14 +00:00
David Stenberg 3889ff82bf [DebugInfo] Refactor DIExpression [SZ]Ext creation into function [NFC]
Summary:
Also, replace the SmallVector with a normal C array.

Reviewers: vsk

Reviewed By: vsk

Subscribers: hiraditya, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D70498
2019-11-21 10:44:04 +01:00
Vedant Kumar a087b78bc4 Wrong debug info generated at -O2 (-O0 is correct)
Instcombiner pass was erasing trivially dead instruction without updating dependent llvm.dbg.value.
which was not showing programmer current state of variables while debugging.
As a part of this fix I did following,
Iterate throught all the users (llvm.dbg) of a instruction which is trivially dead and set each if them undef, Before deleting the instruction.
Now user will see optimized out, when try to print those variables.
This fixes
https://bugs.llvm.org/show_bug.cgi?id=43893

This is my first fix to llvm.

Patch by kamlesh kumar!

Differential Revision: https://reviews.llvm.org/D69809
2019-11-07 11:19:41 -08:00
Guillaume Chatelet 0e62011df8 [Alignment][NFC] Remove dependency on GlobalObject::setAlignment(unsigned)
Summary:
This is patch is part of a series to introduce an Alignment type.
See this thread for context: http://lists.llvm.org/pipermail/llvm-dev/2019-July/133851.html
See this patch for the introduction of the type: https://reviews.llvm.org/D64790

Reviewers: courbet

Subscribers: arsenm, mehdi_amini, jvesely, nhaehnle, hiraditya, steven_wu, dexonsmith, dang, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D68944

llvm-svn: 374880
2019-10-15 11:24:36 +00:00
Florian Hahn a80b6c1542 [Local] Handle terminators with users in removeUnreachableBlocks.
Terminators like invoke can have users outside the current basic block.
We have to replace those users with undef, before replacing the
terminator.

This fixes a crash exposed by rL373430.

Reviewers: brzycki, asbirlea, davide, spatel

Reviewed By: asbirlea

Differential Revision: https://reviews.llvm.org/D68327

llvm-svn: 373513
2019-10-02 19:38:24 +00:00
Florian Hahn eb6700b57e [Local] Remove unused LazyValueInfo pointer from removeUnreachableBlock.
There are no users that pass in LazyValueInfo, so we can simplify the
function a bit.

Reviewers: brzycki, asbirlea, davide

Reviewed By: davide

Differential Revision: https://reviews.llvm.org/D68297

llvm-svn: 373488
2019-10-02 16:58:13 +00:00
Florian Hahn 167b0529be [Local] Simplify function removeUnreachableBlocks() to avoid (re-)computation.
Two small changes in llvm::removeUnreachableBlocks() to avoid unnecessary (re-)computation.

First, replace the use of count() with find(), which has better time complexity.

Second, because we have already computed the set of dead blocks, replace the second loop over all basic blocks to a loop only over the already computed dead blocks. This simplifies the loop and avoids recomputation.

Patch by Rodrigo Caetano Rocha <rcor.cs@gmail.com>

Reviewers: efriedma, spatel, fhahn, xbolva00

Reviewed By: fhahn, xbolva00

Differential Revision: https://reviews.llvm.org/D68191

llvm-svn: 373429
2019-10-02 07:37:41 +00:00
Guillaume Chatelet ab11b9188d [Alignment][NFC] Remove AllocaInst::setAlignment(unsigned)
Summary:
This is patch is part of a series to introduce an Alignment type.
See this thread for context: http://lists.llvm.org/pipermail/llvm-dev/2019-July/133851.html
See this patch for the introduction of the type: https://reviews.llvm.org/D64790

Reviewers: courbet

Subscribers: jholewinski, arsenm, jvesely, nhaehnle, eraman, hiraditya, cfe-commits, llvm-commits

Tags: #clang, #llvm

Differential Revision: https://reviews.llvm.org/D68141

llvm-svn: 373207
2019-09-30 13:34:44 +00:00
Guillaume Chatelet 18f805a7ea [Alignment][NFC] Remove unneeded llvm:: scoping on Align types
llvm-svn: 373081
2019-09-27 12:54:21 +00:00
Alexey Lapshin cbf1f3b771 [Debuginfo][SROA] Need to handle dbg.value in SROA pass.
SROA pass processes debug info incorrecly if applied twice.
Specifically, after SROA works first time, instcombine converts dbg.declare
intrinsics into dbg.value. Inlining creates new opportunities for SROA,
so it is called again. This time it does not handle correctly previously
inserted dbg.value intrinsics.

Differential Revision: https://reviews.llvm.org/D64595

llvm-svn: 370906
2019-09-04 14:19:49 +00:00
Johannes Doerfert 3d7bbc6f9c [Attributor][Fix] Do not remove instructions during manifestation
When we remove instructions cached references could still be live. This
patch avoids removing invoke instructions that are replaced by calls and
instead keeps them around but in a dead block.

llvm-svn: 367933
2019-08-05 21:35:02 +00:00
Guillaume Chatelet 65e4b47aad [LLVM][Alignment] Introduce Alignment Type in DataLayout
Summary:
This is patch is part of a serie to introduce an Alignment type.
See this thread for context: http://lists.llvm.org/pipermail/llvm-dev/2019-July/133851.html
See this patch for the introduction of the type: https://reviews.llvm.org/D64790

Reviewers: courbet, jfb, jakehehrlich

Subscribers: hiraditya, dexonsmith, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D65521

Make getFunctionPtrAlign() return MaybeAlign

llvm-svn: 367817
2019-08-05 09:00:43 +00:00
Yonghong Song 44b16bd4a5 [Transforms] Do not drop !preserve.access.index metadata
Currently, when a GVN or CSE optimization happens,
the llvm.preserve.access.index metadata is dropped.
This caused a problem for BPF AbstructMemberOffset phase
as it relies on the metadata (debuginfo types).

This patch added proper hooks in lib/Transforms to
preserve !preserve.access.index metadata. A test
case is added to ensure metadata is preserved under CSE.

Differential Revision: https://reviews.llvm.org/D65700

llvm-svn: 367769
2019-08-03 23:41:26 +00:00
Sanjay Patel 38a0200868 [Utils] remove duplicated documentation comments; NFC
http://llvm.org/docs/CodingStandards.html#doxygen-use-in-documentation-comments

llvm-svn: 367015
2019-07-25 13:11:21 +00:00
Sanjay Patel 86e9f9dc26 [Transforms] move copying of load metadata to helper function; NFC
There's another proposed load combine that can make use of this code
in D64432.

llvm-svn: 366949
2019-07-24 22:11:11 +00:00
Petr Hosek 8b161bacf4 [SafeStack] Insert the deref before remaining elements
This is a follow up to D64971. While we need to insert the deref after
the offset, it needs to come before the remaining elements in the
original expression since the deref needs to happen before the LLVM
fragment if present.

Differential Revision: https://reviews.llvm.org/D65172

llvm-svn: 366865
2019-07-24 00:16:23 +00:00
Stefan Stipanovic 6058b86373 Fixing build error from commit 95cbc3d
[Attributor] Liveness analysis.

Liveness analysis abstract attribute used to indicate which BasicBlocks are dead and can therefore be ignored.
Right now we are only looking at noreturn calls.

Reviewers: jdoerfert, uenoku

Subscribers: hiraditya, llvm-commits

Differential Revision: https://reviews.llvm.org/D64162

llvm-svn: 366769
2019-07-22 23:58:23 +00:00
Stefan Stipanovic 5a9ba27c71 Revert "Fixing build error from commit 9285295."
This reverts commit 95cbc3da88.

llvm-svn: 366759
2019-07-22 22:55:05 +00:00
Stefan Stipanovic 95cbc3da88 Fixing build error from commit 9285295.
[Attributor] Liveness analysis.

Liveness analysis abstract attribute used to indicate which BasicBlocks are dead and can therefore be ignored.
Right now we are only looking at noreturn calls.

Reviewers: jdoerfert, uenoku

Subscribers: hiraditya, llvm-commits

Differential revision: https://reviews.llvm.org/D64162

llvm-svn: 366753
2019-07-22 22:10:59 +00:00
Eric Christopher 77dc6d2479 Temporarily Revert "[Attributor] Liveness analysis." as it's breaking the build.
This reverts commit 9285295f75.

llvm-svn: 366737
2019-07-22 21:04:23 +00:00
Stefan Stipanovic 9285295f75 [Attributor] Liveness analysis.
Liveness analysis abstract attribute used to indicate which BasicBlocks are dead and can therefore be ignored.
Right now we are only looking at noreturn calls.

Reviewers: jdoerfert, uenoku

Subscribers: hiraditya, llvm-commits

Differential revision: https://reviews.llvm.org/D64162

llvm-svn: 366736
2019-07-22 20:54:30 +00:00
Petr Hosek f6cd6ffbc9 [SafeStack] Insert the deref after the offset
While debugging code that uses SafeStack, we've noticed that LLVM
produces an invalid DWARF. Concretely, in the following example:

  int main(int argc, char* argv[]) {
    std::string value = "";
    printf("%s\n", value.c_str());
    return 0;
  }

DWARF would describe the value variable as being located at:

  DW_OP_breg14 R14+0, DW_OP_deref, DW_OP_constu 0x20, DW_OP_minus

The assembly to get this variable is:

  leaq    -32(%r14), %rbx

The order of operations in the DWARF symbols is incorrect in this case.
Specifically, the deref is incorrect; this appears to be incorrectly
re-inserted in repalceOneDbgValueForAlloca.

With this change which inserts the deref after the offset instead of
before it, LLVM produces correct DWARF:

  DW_OP_breg14 R14-32

Differential Revision: https://reviews.llvm.org/D64971

llvm-svn: 366726
2019-07-22 18:52:42 +00:00
Florian Hahn 0a7faa4e3d [Local] Zap blockaddress without users in ConstantFoldTerminator.
If the blockaddress is not destoryed, the destination block will still
be marked as having its address taken, limiting further transformations.

I think there are other places where the dead blockaddress constants are kept
around, I'll look into that as follow up.

Reviewers: craig.topper, brzycki, davide

Reviewed By: brzycki, davide

Differential Revision: https://reviews.llvm.org/D64936

llvm-svn: 366633
2019-07-20 12:25:47 +00:00
Alina Sbirlea db101864bd [MemorySSA] Use SetVector to avoid nondeterminism.
Summary:
Use a SetVector for DeadBlockSet.
Resolves PR42574.

Reviewers: george.burgess.iv, uabelho, dblaikie

Subscribers: jlebar, Prazek, mgrang, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D64601

llvm-svn: 365970
2019-07-12 22:30:30 +00:00
Bob Haarman 032f87bbb3 Revert r360902 "Resubmit: [Salvage] Change salvage debug info ..."
This reverts commit rr360902. It caused an assertion failure in
lib/IR/DebugInfoMetadata.cpp: Assertion `(OffsetInBits + SizeInBits <=
FragmentSizeInBits) && "new fragment outside of original fragment"'
failed.

PR41931.

llvm-svn: 361246
2019-05-21 11:53:41 +00:00
Petar Jovanovic e85bbf564d [DebugInfoMetadata] Refactor DIExpression::prepend constants (NFC)
Refactor DIExpression::With* into a flag enum in order to be less
error-prone to use (as discussed on D60866).

Patch by Djordje Todorovic.

Differential Revision: https://reviews.llvm.org/D61943

llvm-svn: 361137
2019-05-20 10:35:57 +00:00
Stephen Tozer 6f59b4b6d9 Resubmit: [Salvage] Change salvage debug info implementation to use DW_OP_LLVM_convert where needed
Fixes issue: https://bugs.llvm.org/show_bug.cgi?id=40645

Previously, LLVM had no functional way of performing casts inside of a
DIExpression(), which made salvaging cast instructions other than Noop casts
impossible. With the recent addition of DW_OP_LLVM_convert this salvaging is
now possible, and so can be used to fix the attached bug as well as any cases
where SExt instruction results are lost in the debugging metadata. This patch
introduces this fix by expanding the salvage debug info method to cover these
cases using the new operator.

Differential revision: https://reviews.llvm.org/D61184

llvm-svn: 360902
2019-05-16 14:41:01 +00:00
Stephen Tozer 0d02f2ff4f Revert "[Salvage] Change salvage debug info implementation to use DW_OP_LLVM_convert where needed"
This reverts r360772 due to build issues.
Reverted commit: 17dd4d7403.

llvm-svn: 360773
2019-05-15 13:41:44 +00:00
Stephen Tozer 17dd4d7403 [Salvage] Change salvage debug info implementation to use DW_OP_LLVM_convert where needed
Fixes issue: https://bugs.llvm.org/show_bug.cgi?id=40645

Previously, LLVM had no functional way of performing casts inside of a
DIExpression(), which made salvaging cast instructions other than Noop
casts impossible. With the recent addition of DW_OP_LLVM_convert this
salvaging is now possible, and so can be used to fix the attached bug as
well as any cases where SExt instruction results are lost in the
debugging metadata. This patch introduces this fix by expanding the
salvage debug info method to cover these cases using the new operator.

Differential revision: https://reviews.llvm.org/D61184

llvm-svn: 360772
2019-05-15 13:15:48 +00:00
Jeremy Morse a2b780b731 [DebugInfo] Use zero linenos for debug intrinsics when promoting dbg.declare
In certain circumstances, optimizations pick line numbers from debug
intrinsic instructions as the new location for altered instructions. This
is problematic because the line number of a debugging intrinsic is
meaningless (it doesn't produce any machine instruction), only the scope
information is valid. The result can be the line number of a variable
declaration "leaking" into real code from debugging intrinsics, making the
line table un-necessarily jumpy, and potentially different with / without
variable locations.

Fix this by using zero line numbers when promoting dbg.declare intrinsics
into dbg.values: this is safe for debug intrinsics as their line numbers
are meaningless, and reduces the scope for damage / misleading stepping
when optimizations pick locations from the wrong place.

Differential Revision: https://reviews.llvm.org/D59272

llvm-svn: 360415
2019-05-10 10:03:41 +00:00
David Stuttard 411488b11e [CodeGenPrepare] Limit recursion depth for collectBitParts
Summary:
Seeing some issues for windows debug pathological cases with collectBitParts
recursion (1525 levels of recursion!)
Setting the limit to 64 as this should be sufficient - passes all lit cases

Subscribers: llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D61728

Change-Id: I7f44cdc6c1badf1c2ccbf1b0c4b6afe27ecb39a1
llvm-svn: 360347
2019-05-09 15:02:10 +00:00
Alina Sbirlea f31eba6494 [MemorySSA] Teach LoopSimplify to preserve MemorySSA.
Summary:
Preserve MemorySSA in LoopSimplify, in the old pass manager, if the analysis is available.
Do not preserve it in the new pass manager.
Update tests.

Subscribers: nemanjai, jlebar, javed.absar, Prazek, kbarton, zzheng, jsji, llvm-commits, george.burgess.iv, chandlerc

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D60833

llvm-svn: 360270
2019-05-08 17:05:36 +00:00
Wolfgang Pieb 4fe42214e2 [DEBUGINFO] Prevent Instcombine from dropping debuginfo when removing zexts
Zexts can be treated like no-op casts when it comes to assessing whether their
removal affects debug info.

Reviewer: aprantl

Differential Revision: https://reviews.llvm.org/D60641

llvm-svn: 358431
2019-04-15 17:36:29 +00:00
Alexander Potapenko 6a63e5aa7b [Transforms][ASan] Move findAllocaForValue() to Utils/Local.cpp. NFC
Summary:
Factor out findAllocaForValue() from ASan so that we can use it in
MSan to handle lifetime intrinsics.

Reviewers: eugenis, pcc

Subscribers: hiraditya, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D60615

llvm-svn: 358380
2019-04-15 08:59:56 +00:00
Joseph Tremoulet fb4d9f7287 [SimplifyCFG] Don't split musttail call from ret
Summary:
When inserting an `unreachable` after a noreturn call, we must ensure
that it's not a musttail call to avoid breaking the IR invariants for
musttail calls.

Reviewers: fedor.sergeev, majnemer

Reviewed By: majnemer

Subscribers: hiraditya, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D60080

llvm-svn: 357485
2019-04-02 15:48:58 +00:00
Brian Gesiak 1c44ed8b76 [Transforms] Redundant getValueOperand (NFC)
`StoreInst::getValueOperand` is identical to `getOperand(0)`, so the call to
`getOperand(0)` can be replaced. Further, `SI->getValueOperand` is redundantly
called just a few lines down, despite its return value being stored in variable
`DV`. No functional change.

llvm-svn: 357479
2019-04-02 14:57:56 +00:00
Markus Lavin b86ce219f4 [DebugInfo] Introduce DW_OP_LLVM_convert
Introduce a DW_OP_LLVM_convert Dwarf expression pseudo op that allows
for a convenient way to perform type conversions on the Dwarf expression
stack. As an additional bonus it paves the way for using other Dwarf
v5 ops that need to reference a base_type.

The new DW_OP_LLVM_convert is used from lib/Transforms/Utils/Local.cpp
to perform sext/zext on debug values but mainly the patch is about
preparing terrain for adding other Dwarf v5 ops that need to reference a
base_type.

For Dwarf v5 the op maps to DW_OP_convert and for earlier versions a
complex shift & mask pattern is generated to emulate sext/zext.

This is a recommit of r356442 with trivial fixes for the failing tests.

Differential Revision: https://reviews.llvm.org/D56587

llvm-svn: 356451
2019-03-19 13:16:28 +00:00
Markus Lavin ad78768d59 Revert "[DebugInfo] Introduce DW_OP_LLVM_convert"
This reverts commit 1cf4b593a7ebd666fc6775f3bd38196e8e65fafe.

Build bots found failing tests not detected locally.

Failing Tests (3):
  LLVM :: DebugInfo/Generic/convert-debugloc.ll
  LLVM :: DebugInfo/Generic/convert-inlined.ll
  LLVM :: DebugInfo/Generic/convert-linked.ll

llvm-svn: 356444
2019-03-19 09:17:28 +00:00
Markus Lavin cd8a940b37 [DebugInfo] Introduce DW_OP_LLVM_convert
Introduce a DW_OP_LLVM_convert Dwarf expression pseudo op that allows
for a convenient way to perform type conversions on the Dwarf expression
stack. As an additional bonus it paves the way for using other Dwarf
v5 ops that need to reference a base_type.

The new DW_OP_LLVM_convert is used from lib/Transforms/Utils/Local.cpp
to perform sext/zext on debug values but mainly the patch is about
preparing terrain for adding other Dwarf v5 ops that need to reference a
base_type.

For Dwarf v5 the op maps to DW_OP_convert and for earlier versions a
complex shift & mask pattern is generated to emulate sext/zext.

Differential Revision: https://reviews.llvm.org/D56587

llvm-svn: 356442
2019-03-19 08:48:19 +00:00
Chijun Sima 70e97163e0 [DTU] Refine the interface and logic of applyUpdates
Summary:
This patch separates two semantics of `applyUpdates`:
1. User provides an accurate CFG diff and the dominator tree is updated according to the difference of `the number of edge insertions` and `the number of edge deletions` to infer the status of an edge before and after the update.
2. User provides a sequence of hints. Updates mentioned in this sequence might never happened and even duplicated.

Logic changes:

Previously, removing invalid updates is considered a side-effect of deduplication and is not guaranteed to be reliable. To handle the second semantic, `applyUpdates` does validity checking before deduplication, which can cause updates that have already been applied to be submitted again. Then, different calls to `applyUpdates` might cause unintended consequences, for example,
```
DTU(Lazy) and Edge A->B exists.
1. DTU.applyUpdates({{Delete, A, B}, {Insert, A, B}}) // User expects these 2 updates result in a no-op, but {Insert, A, B} is queued
2. Remove A->B
3. DTU.applyUpdates({{Delete, A, B}}) // DTU cancels this update with {Insert, A, B} mentioned above together (Unintended)
```
But by restricting the precondition that updates of an edge need to be strictly ordered as how CFG changes were made, we can infer the initial status of this edge to resolve this issue.

Interface changes:
The second semantic of `applyUpdates`  is separated to `applyUpdatesPermissive`.
These changes enable DTU(Lazy) to use the first semantic if needed, which is quite useful in `transforms/utils`.

Reviewers: kuhar, brzycki, dmgreen, grosser

Reviewed By: brzycki

Subscribers: hiraditya, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D58170

llvm-svn: 354669
2019-02-22 13:48:38 +00:00
Chijun Sima f131d6110e [DTU] Deprecate insertEdge*/deleteEdge*
Summary: This patch converts all existing `insertEdge*/deleteEdge*` to `applyUpdates` and marks `insertEdge*/deleteEdge*` as deprecated.

Reviewers: kuhar, brzycki

Reviewed By: kuhar, brzycki

Subscribers: hiraditya, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D58443

llvm-svn: 354652
2019-02-22 05:41:43 +00:00
Jeremy Morse b33a5c7347 [DebugInfo] Don't salvage load operations (PR40628).
Salvaging a redundant load instruction into a debug expression hides a
memory read from optimisation passes. Passes that alter memory behaviour
(such as LICM promoting memory to a register) aren't aware of these debug
memory reads and leave them unaltered, making the debug variable location
point somewhere unsafe.

Teaching passes to know about these debug memory reads would be challenging
and probably incomplete. Finding dbg.value instructions that need to be fixed
would likely be computationally expensive too, as more analysis would be
required. It's better to not generate debug-memory-reads instead, alas.

Changed tests:
 * DeadStoreElim: test for salvaging of intermediate operations contributing
   to the dead store, instead of salvaging of the redundant load,
 * GVN: remove debuginfo behaviour checks completely, this behaviour is still
   covered by other tests,
 * InstCombine: don't test for salvaged loads, we're removing that behaviour.

Differential Revision: https://reviews.llvm.org/D57962

llvm-svn: 353824
2019-02-12 10:54:30 +00:00
Chandler Carruth 751d95fb9b [CallSite removal] Migrate ConstantFolding APIs and implementation to
`CallBase`.

Users have been updated. You can see how to update any out-of-tree
usages: pass `cast<CallBase>(CS.getInstruction())`.

llvm-svn: 353661
2019-02-11 07:51:44 +00:00
Chandler Carruth 3160734af1 [CallSite removal] Migrate the statepoint GC infrastructure to use the
`CallBase` class rather than `CallSite` wrappers.

I pushed this change down through most of the statepoint infrastructure,
completely removing the use of CallSite where I could reasonably do so.
I ended up making a couple of cut-points: generic call handling
(instcombine, TLI, SDAG). As soon as it hit truly generic handling with
users outside the immediate code, I simply transitioned into or out of
a `CallSite` to make this a reasonable sized chunk.

Differential Revision: https://reviews.llvm.org/D56122

llvm-svn: 353660
2019-02-11 07:42:30 +00:00
Fangrui Song 709a3e7488 [Local] Delete a redundant check. NFC
isInstructionTriviallyDead also performs the use_empty() check.

llvm-svn: 353637
2019-02-10 09:25:56 +00:00
Craig Topper 784929d045 Implementation of asm-goto support in LLVM
This patch accompanies the RFC posted here:
http://lists.llvm.org/pipermail/llvm-dev/2018-October/127239.html

This patch adds a new CallBr IR instruction to support asm-goto
inline assembly like gcc as used by the linux kernel. This
instruction is both a call instruction and a terminator
instruction with multiple successors. Only inline assembly
usage is supported today.

This also adds a new INLINEASM_BR opcode to SelectionDAG and
MachineIR to represent an INLINEASM block that is also
considered a terminator instruction.

There will likely be more bug fixes and optimizations to follow
this, but we felt it had reached a point where we would like to
switch to an incremental development model.

Patch by Craig Topper, Alexander Ivchenko, Mikhail Dvoretckii

Differential Revision: https://reviews.llvm.org/D53765

llvm-svn: 353563
2019-02-08 20:48:56 +00:00
Carlos Alberto Enciso 08dc50f2fb [DWARF] LLVM ERROR: Broken function found, while removing Debug Intrinsics.
Check that when SimplifyCFG is flattening a 'br', all their debug intrinsic instructions are removed, including any dbg.label referencing a label associated with the basic blocks being removed.

Differential Revision: https://reviews.llvm.org/D57444

llvm-svn: 353511
2019-02-08 10:57:26 +00:00
Richard Trieu 5f436fc57a Move DomTreeUpdater from IR to Analysis
DomTreeUpdater depends on headers from Analysis, but is in IR.  This is a
layering violation since Analysis depends on IR.  Relocate this code from IR
to Analysis to fix the layering violation.

llvm-svn: 353265
2019-02-06 02:52:52 +00:00
Jeremy Morse 84ca706be1 [DebugInfo][NFCI] Split salvageDebugInfo into helper functions
Some use cases are appearing where salvaging is needed that does not
correspond to an instruction being deleted -- for example an instruction
being sunk, or a Value not being available in a block being isel'd.

Enable more fine grained control over how salavging occurs by splitting
the logic into helper functions, separating things that are specific to
working on DbgVariableIntrinsics from those specific to interpreting IR
and building DIExpressions.

Differential Revision: https://reviews.llvm.org/D57696

llvm-svn: 353156
2019-02-05 11:11:28 +00:00
James Y Knight d9e85a0861 [opaque pointer types] Pass function types to InvokeInst creation.
This cleans up all InvokeInst creation in LLVM to explicitly pass a
function type rather than deriving it from the pointer's element-type.

Differential Revision: https://reviews.llvm.org/D57171

llvm-svn: 352910
2019-02-01 20:43:34 +00:00
James Y Knight 7976eb5838 [opaque pointer types] Pass function types to CallInst creation.
This cleans up all CallInst creation in LLVM to explicitly pass a
function type rather than deriving it from the pointer's element-type.

Differential Revision: https://reviews.llvm.org/D57170

llvm-svn: 352909
2019-02-01 20:43:25 +00:00
Chandler Carruth 2946cd7010 Update the file headers across all of the LLVM projects in the monorepo
to reflect the new license.

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

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

llvm-svn: 351636
2019-01-19 08:50:56 +00:00
Vedant Kumar b264d69de7 [IR] Add Instruction::isLifetimeStartOrEnd, NFC
Instruction::isLifetimeStartOrEnd() checks whether an Instruction is an
llvm.lifetime.start or an llvm.lifetime.end intrinsic.

This was suggested as a cleanup in D55967.

Differential Revision: https://reviews.llvm.org/D56019

llvm-svn: 349964
2018-12-21 21:49:40 +00:00
Michael Kruse 978ba61536 Introduce llvm.loop.parallel_accesses and llvm.access.group metadata.
The current llvm.mem.parallel_loop_access metadata has a problem in that
it uses LoopIDs. LoopID unfortunately is not loop identifier. It is
neither unique (there's even a regression test assigning the some LoopID
to multiple loops; can otherwise happen if passes such as LoopVersioning
make copies of entire loops) nor persistent (every time a property is
removed/added from a LoopID's MDNode, it will also receive a new LoopID;
this happens e.g. when calling Loop::setLoopAlreadyUnrolled()).
Since most loop transformation passes change the loop attributes (even
if it just to mark that a loop should not be processed again as
llvm.loop.isvectorized does, for the versioned and unversioned loop),
the parallel access information is lost for any subsequent pass.

This patch unlinks LoopIDs and parallel accesses.
llvm.mem.parallel_loop_access metadata on instruction is replaced by
llvm.access.group metadata. llvm.access.group points to a distinct
MDNode with no operands (avoiding the problem to ever need to add/remove
operands), called "access group". Alternatively, it can point to a list
of access groups. The LoopID then has an attribute
llvm.loop.parallel_accesses with all the access groups that are parallel
(no dependencies carries by this loop).

This intentionally avoid any kind of "ID". Loops that are clones/have
their attributes modifies retain the llvm.loop.parallel_accesses
attribute. Access instructions that a cloned point to the same access
group. It is not necessary for each access to have it's own "ID" MDNode,
but those memory access instructions with the same behavior can be
grouped together.

The behavior of llvm.mem.parallel_loop_access is not changed by this
patch, but should be considered deprecated.

Differential Revision: https://reviews.llvm.org/D52116

llvm-svn: 349725
2018-12-20 04:58:07 +00:00
Vedant Kumar 9d1827331f [Util] Refer to [s|z]exts of args when converting dbg.declares (fix PR35400)
When converting dbg.declares, if the described value is a [s|z]ext,
refer to the ext directly instead of referring to its operand.

This fixes a narrowing bug (the debugger got the sign of a variable
wrong, see llvm.org/PR35400).

The main reason to refer to the ext's operand was that an optimization
may remove the ext itself, leading to a dropped variable. Now that
InstCombine has been taught to use replaceAllDbgUsesWith (r336451), this
is less of a concern. Other passes can/should adopt this API as needed
to fix dropped variable bugs.

Differential Revision: https://reviews.llvm.org/D51813

llvm-svn: 349214
2018-12-15 00:03:33 +00:00
Michael Kruse 5948b7f30f [Transforms] Preserve metadata when converting invoke to call.
The `changeToCall` function did not preserve the invoke's metadata.
Currently, there is probably no metadata that depends on being applied
on a CallInst or InvokeInst. Therefore we can replace the instruction's
metadata.

This fixes http://llvm.org/PR39994

Suggested-by: Moritz Kreutzer <moritz.kreutzer@siemens.com>

Differential Revision: https://reviews.llvm.org/D55666

llvm-svn: 349170
2018-12-14 18:15:11 +00:00
Davide Italiano 8ec7709f58 [Local] Promote an utility that could be used elsewhere. NFCI.
llvm-svn: 348804
2018-12-10 22:17:04 +00:00
Vedant Kumar 4de31bba51 [IR] Add hasNPredecessors, hasNPredecessorsOrMore to BasicBlock
Add methods to BasicBlock which make it easier to efficiently check
whether a block has N (or more) predecessors.

This can be more efficient than using pred_size(), which is a linear
time operation.

We might consider adding similar methods for successors. I haven't done
so in this patch because succ_size() is already O(1).

With this patch applied, I measured a 0.065% compile-time reduction in
user time for running `opt -O3` on the sqlite3 amalgamation (30 trials).
The change in mergeStoreIntoSuccessor alone saves 45 million linked list
iterations in a stage2 Release build of llc.

See llvm.org/PR39702 for a harder but more general way of achieving
similar results.

Differential Revision: https://reviews.llvm.org/D54686

llvm-svn: 347256
2018-11-19 19:54:27 +00:00
Florian Hahn fc7654a67b [Local] Keep K's range if K does not move when combining metadata.
As K has to dominate I, IIUC I's range metadata must be a subset of
K's. After Eli's recent clarification to the LangRef, loading a value
outside of the range is undefined behavior.
Therefore if I's range contains elements outside of K's range and we would load
one such value, K would cause undefined behavior.

In cases like hoisting/sinking, we still want the most generic range
over all code paths to/from the hoist/sink point. As suggested in the
patches related to D47339, I will refactor the handling of those
scenarios and try to decouple it from this function as follow up, once
we switched to a similar handling of metadata in most of
combineMetadata.

I updated some tests checking mostly the merging of metadata to keep the
metadata of to dominating load. The most interesting one is probably test8 in
test/Transforms/JumpThreading/thread-loads.ll. It contained a comment
about the alias metadata preventing us to eliminate the branch, but it
seem like the actual problem currently is that we merge the ranges of
both loads and cannot eliminate the icmp afterwards. With this patch, we
manage to eliminate the icmp, as the range of the first load excludes 8.

Reviewers: efriedma, nlopes, davide

Reviewed By: efriedma

Differential Revision: https://reviews.llvm.org/D51629

llvm-svn: 345456
2018-10-27 16:53:45 +00:00