Summary:
Bug: https://bugs.llvm.org/show_bug.cgi?id=39024
The bug reports that a vectorized loop is stepped through 4 times and each step through the loop seemed to show a different path. I found two problems here:
A) An incorrect line number on a preheader block (for.body.preheader) instruction causes a step into the loop before it begins.
B) Instructions in the middle block have different line numbers which give the impression of another iteration.
In this patch I give all of the middle block instructions the line number of the scalar loop latch terminator branch. This seems to provide the smoothest debugging experience because the vectorized loops will always end on this line before dropping into the scalar loop. To solve problem A I have altered llvm::SplitBlockPredecessors to accommodate loop header blocks.
I have set up a separate review D61933 for a fix which is required for this patch.
Reviewers: samsonov, vsk, aprantl, probinson, anemet, hfinkel, jmorse
Reviewed By: hfinkel, jmorse
Subscribers: jmorse, javed.absar, eraman, kcc, bjope, jmellorcrummey, hfinkel, gbedwell, hiraditya, zzheng, llvm-commits
Tags: #llvm, #debug-info
Differential Revision: https://reviews.llvm.org/D60831
> llvm-svn: 363046
llvm-svn: 363786
Using the new SwitchInstProfUpdateWrapper this patch
simplifies 3 places of prof branch_weights handling.
Differential Revision: https://reviews.llvm.org/D62123
llvm-svn: 363652
Summary:
There is PHINode::getBasicBlockIndex() and PHINode::setIncomingValue()
but no function to replace incoming value for a specified BasicBlock*
predecessor.
Clearly, there are a lot of places that could use that functionality.
Reviewer: craig.topper, lebedev.ri, Meinersbur, kbarton, fhahn
Reviewed By: Meinersbur, fhahn
Subscribers: fhahn, hiraditya, zzheng, jsji, llvm-commits
Tag: LLVM
Differential Revision: https://reviews.llvm.org/D63338
llvm-svn: 363566
Third time's the charm.
This was reverted in r363220 due to being suspected of an internal benchmark
regression and a test failure, none of which turned out to be caused by this.
llvm-svn: 363529
SimplifyCFG has a bug that results in inconsistent prof branch_weights metadata
if unreachable switch cases are removed. This patch fixes this bug by making use
of the newly introduced SwitchInstProfUpdateWrapper class (see patch D62122).
A new test is created.
Differential Revision: https://reviews.llvm.org/D62186
llvm-svn: 363527
If we can detect that saturating math that depends on an IV cannot
overflow, replace it with simple math. This is similar to the CVP
optimization from D62703, just based on a different underlying
analysis (SCEV vs LVI) that catches different cases.
Differential Revision: https://reviews.llvm.org/D62792
llvm-svn: 363489
and replace with an equilivent countTrailingZeros.
GCD is much more expensive than this, with repeated division.
This depends on D60823
Differential Revision: https://reviews.llvm.org/D61151
llvm-svn: 363422
This reverts 363226 and 363227, both NFC intended
I swear I fixed the test case that is failing, and ran
the tests, but I will look into it again.
llvm-svn: 363229
and replace with an equilivent countTrailingZeros.
GCD is much more expensive than this, with repeated division.
This depends on D60823
Differential Revision: https://reviews.llvm.org/D61151
llvm-svn: 363227
We have observed some failures with internal builds with this revision.
- Performance regressions:
- llvm's SingleSource/Misc evalloop shows performance regressions (although these may be red herrings).
- Benchmarks for Abseil's SwissTable.
- Correctness:
- Failures for particular libicu tests when building the Google AppEngine SDK (for PHP).
hwennborg has already been notified, and is aware of reproducer failures.
llvm-svn: 363220
This changes the standalone pass only. Arguably the utility class
itself should assert there are no convergent calls. However, a target
pass with additional context may still be able to version a loop if
all of the dynamic conditions are sufficiently uniform.
llvm-svn: 363165
We were only matching RHS being a loop invariant value, not the inverse. Since there's nothing which appears to canonicalize loop invariant values to RHS, this means we missed cases.
Differential Revision: https://reviews.llvm.org/D63112
llvm-svn: 363108
Summary:
Bug: https://bugs.llvm.org/show_bug.cgi?id=39024
The bug reports that a vectorized loop is stepped through 4 times and each step through the loop seemed to show a different path. I found two problems here:
A) An incorrect line number on a preheader block (for.body.preheader) instruction causes a step into the loop before it begins.
B) Instructions in the middle block have different line numbers which give the impression of another iteration.
In this patch I give all of the middle block instructions the line number of the scalar loop latch terminator branch. This seems to provide the smoothest debugging experience because the vectorized loops will always end on this line before dropping into the scalar loop. To solve problem A I have altered llvm::SplitBlockPredecessors to accommodate loop header blocks.
I have set up a separate review D61933 for a fix which is required for this patch.
Reviewers: samsonov, vsk, aprantl, probinson, anemet, hfinkel, jmorse
Reviewed By: hfinkel, jmorse
Subscribers: jmorse, javed.absar, eraman, kcc, bjope, jmellorcrummey, hfinkel, gbedwell, hiraditya, zzheng, llvm-commits
Tags: #llvm, #debug-info
Differential Revision: https://reviews.llvm.org/D60831
llvm-svn: 363046
This patch changes how LLVM handles the accumulator/start value
in the reduction, by never ignoring it regardless of the presence of
fast-math flags on callsites. This change introduces the following
new intrinsics to replace the existing ones:
llvm.experimental.vector.reduce.fadd -> llvm.experimental.vector.reduce.v2.fadd
llvm.experimental.vector.reduce.fmul -> llvm.experimental.vector.reduce.v2.fmul
and adds functionality to auto-upgrade existing LLVM IR and bitcode.
Reviewers: RKSimon, greened, dmgreen, nikic, simoll, aemerson
Reviewed By: nikic
Differential Revision: https://reviews.llvm.org/D60261
llvm-svn: 363035
Summary: Move some code around, in preparation for later fixes
to the non-integral addrspace handling (D59661)
Patch By Jameson Nash <jameson@juliacomputing.com>
Reviewed By: reames, loladiro
Differential Revision: https://reviews.llvm.org/D59729
llvm-svn: 362853
Summary:
The cleanup in D62751 introduced a compile-time regression due to the way DT updates are performed.
Add all insert edges then all delete edges in DTU to match the previous compile time.
Compile time on the test provided by @mstorsjo before and after this patch on my machine:
113.046s vs 35.649s
Repro: clang -target x86_64-w64-mingw32 -c -O3 glew-preproc.c; on https://martin.st/temp/glew-preproc.c.
Reviewers: kuhar, NutshellySima, mstorsjo
Subscribers: jlebar, mstorsjo, dmgreen, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D62981
llvm-svn: 362839
Summary:
This change only unifies the API previous API pair accepting
CallInst and InvokeInst, thus making it easier to refactor
inliner pass ode to CallBase. The implementation of the unified
API still relies on the CallSite implementation.
Reviewers: eraman, chandlerc, jdoerfert
Reviewed By: jdoerfert
Subscribers: jdoerfert, hiraditya, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D62283
llvm-svn: 362656
Instead of passing around fast-math-flags as a parameter, we can set those
using an IRBuilder guard object. This is no-functional-change-intended.
The motivation is to eventually fix the vectorizers to use and set the
correct fast-math-flags for reductions. Examples of that not behaving as
expected are:
https://bugs.llvm.org/show_bug.cgi?id=23116 (should be able to reduce with less than 'fast')
https://bugs.llvm.org/show_bug.cgi?id=35538 (possible miscompile for -0.0)
D61802 (should be able to reduce with IR-level FMF)
Differential Revision: https://reviews.llvm.org/D62272
llvm-svn: 362612
Summary:
Following the cleanup in D48202, method foldBlockIntoPredecessor has the
same behavior. Replace its uses with MergeBlockIntoPredecessor.
Remove foldBlockIntoPredecessor.
Reviewers: chandlerc, dmgreen
Subscribers: jlebar, javed.absar, zzheng, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D62751
llvm-svn: 362538
This patch fixes a problem that occurs in LowerSwitch when a switch statement has a PHI node as its condition, and the PHI node only has two incoming blocks, and one of those incoming blocks is through an unreachable default in the switch statement. When this condition occurs, LowerSwitch holds a pointer to the condition value, but removes the switch block as a predecessor of the PHI block, causing the PHI node to be replaced. LowerSwitch then tries to use its stale pointer to the original condition value, causing a crash.
Differential Revision: https://reviews.llvm.org/D62560
llvm-svn: 362427
Extract a willNotOverflow() helper function that is shared between
eliminateOverflowIntrinsic() and strengthenOverflowingOperation().
Use WithOverflowInst for the former.
We'll be able to reuse the same code for saturating intrinsics as
well.
llvm-svn: 362305
When the object size argument is -1, no checking can be done, so calling the
_chk variant is unnecessary. We already did this for a bunch of these
functions.
rdar://50797197
Differential revision: https://reviews.llvm.org/D62358
llvm-svn: 362272
When we switch to opaque pointer types we will need some way to describe
how many bytes a 'byval' parameter should occupy on the stack. This adds
a (for now) optional extra type parameter.
If present, the type must match the pointee type of the argument.
The original commit did not remap byval types when linking modules, which broke
LTO. This version fixes that.
Note to front-end maintainers: if this causes test failures, it's probably
because the "byval" attribute is printed after attributes without any parameter
after this change.
llvm-svn: 362128
This was reverted in r360086 as it was supected of causing mysterious test
failures internally. However, it was never concluded that this patch was the
root cause.
> The code was previously checking that candidates for sinking had exactly
> one use or were a store instruction (which can't have uses). This meant
> we could sink call instructions only if they had a use.
>
> That limitation seemed a bit arbitrary, so this patch changes it to
> "instruction has zero or one use" which seems more natural and removes
> the need to special-case stores.
>
> Differential revision: https://reviews.llvm.org/D59936
llvm-svn: 361811
Rather than gating on "isSwitchDense" (resulting in necessesarily
sparse lookup tables even when they were generated), always run
this quite cheap transform.
This transform is useful not just for generating tables.
LowerSwitch also wants this: read LowerSwitch.cpp:257.
Be careful to not generate worse code, by introducing a
SubThreshold heuristic.
Instead of just sorting by signed, generalize the finding of the
best base.
And now that it is run unconditionally, do not replicate its
functionality in SwitchToLookupTable (which could use a Sub
when having a hole is smaller, hence the SubThreshold
heuristic located in a single place).
This simplifies SwitchToLookupTable, and fixes
some ugly corner cases due to the use of signed numbers,
such as a table containing i16 32768 and 32769, of which
32769 would be interpreted as -32768, and now the code thinks
the table is size 65536.
(We still use unconditional subtraction when building a single-register mask,
but I think this whole block should go when the more general sparse
map is added, which doesn't leave empty holes in the table.)
And the reason test4 and test5 did not trigger was documented wrong:
it was because they were not considered sufficiently "dense".
Also, fix generation of invalid LLVM-IR: shl by bit-width.
llvm-svn: 361727
and replace with an equilivent countTrailingZeros.
GCD is much more expensive than this, with repeated division.
This depends on D60823
llvm-svn: 361726
This matches countLeadingOnes() and countTrailingOnes(), and
APInt's countLeadingZeros() and countTrailingZeros().
(as well as __builtin_clzll())
llvm-svn: 361724
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
This reverts commit 95805bc425.
I've squashed the test fix into this commit.
[DebugInfo] Update loop metadata for inlined loops
Currently, when a loop is cloned while inlining function (A) into function (B)
the loop metadata is copied and then not modified at all. The loop metadata can
encode the loop's start and end DILocations. Therefore, the new inlined loop in
function (B) may have loop metadata which shows start and end locations residing
in function (A).
This patch ensures loop metadata is updated while inlining so that the start and
end DILocations are given the "inlinedAt" operand. I've also added a regression
test for this.
This fix is required for D60831 because that patch uses loop metadata to
determine the DILocation for the branches of new loop preheaders.
Reviewers: aprantl, dblaikie, anemet
Reviewed By: aprantl
Subscribers: eraman, hiraditya, llvm-commits
Tags: #debug-info, #llvm
Differential Revision: https://reviews.llvm.org/D61933
llvm-svn: 361149
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
Summary:
Currently, when a loop is cloned while inlining function (A) into function (B) the loop metadata is copied and then not modified at all. The loop metadata can encode the loop's start and end DILocations. Therefore, the new inlined loop in function (B) may have loop metadata which shows start and end locations residing in function (A).
This patch ensures loop metadata is updated while inlining so that the start and end DILocations are given the "inlinedAt" operand. I've also added a regression test for this.
This fix is required for D60831 because that patch uses loop metadata to determine the DILocation for the branches of new loop preheaders.
Reviewers: aprantl, dblaikie, anemet
Reviewed By: aprantl
Subscribers: eraman, hiraditya, llvm-commits
Tags: #debug-info, #llvm
Differential Revision: https://reviews.llvm.org/D61933
llvm-svn: 361132
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
Summary: We should excluded unreachable operands from processing as their DFS visitation order is undefined. When `renameUses` function sorts `OpsToRename` (https://fburl.com/d2wubn60), the comparator assumes that the parent block of the operand has a corresponding dominator tree node. This is not the case for unreachable operands and crashes the compiler.
Reviewers: dberlin, mgrang, davide
Subscribers: efriedma, hiraditya, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D61154
llvm-svn: 360796
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
The 3-field form was introduced by D3499 in 2014 and the legacy 2-field
form was planned to be removed in LLVM 4.0
For the textual format, this patch migrates the existing 2-field form to
use the 3-field form and deletes the compatibility code.
test/Verifier/global-ctors-2.ll checks we have a friendly error message.
For bitcode, lib/IR/AutoUpgrade UpgradeGlobalVariables will upgrade the
2-field form (add i8* null as the third field).
Reviewed By: rnk, dexonsmith
Differential Revision: https://reviews.llvm.org/D61547
llvm-svn: 360742
LoopSimplify can preserve MemorySSA after r360270.
But the MemorySSA analysis is retrieved and preserved only when the
EnableMSSALoopDependency is set to true. Use the same conditional to
mark the pass as preserved, otherwise subsequent passes will get an
invalid analysis.
Resolves PR41853.
llvm-svn: 360697
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
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
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
Summary:
Bug: https://bugs.llvm.org/show_bug.cgi?id=39024
The bug reports that a vectorized loop is stepped through 4 times and each step through the loop seemed to show a different path. I found two problems here:
A) An incorrect line number on a preheader block (for.body.preheader) instruction causes a step into the loop before it begins.
B) Instructions in the middle block have different line numbers which give the impression of another iteration.
In this patch I give all of the middle block instructions the line number of the scalar loop latch terminator branch. This seems to provide the smoothest debugging experience because the vectorized loops will always end on this line before dropping into the scalar loop. To solve problem A I have altered llvm::SplitBlockPredecessors to accommodate loop header blocks.
Reviewers: samsonov, vsk, aprantl, probinson, anemet, hfinkel
Reviewed By: hfinkel
Subscribers: bjope, jmellorcrummey, hfinkel, gbedwell, hiraditya, zzheng, llvm-commits
Tags: #llvm, #debug-info
Differential Revision: https://reviews.llvm.org/D60831
llvm-svn: 360162
This reverts r357452 (git commit 21eb771dcb).
This was causing strange optimization-related test failures on an internal test. Will followup with more details offline.
llvm-svn: 360086
Orlando Cazalet-Hyams