Commit Graph

4253 Commits

Author SHA1 Message Date
Max Kazantsev
37da4333a8 [SimplifyIndVars] Eliminate redundant truncs
This patch adds logic to deal with the following constructions:

  %iv = phi i64 ...
  %trunc = trunc i64 %iv to i32
  %cmp = icmp <pred> i32 %trunc, %invariant

Replacing it with
  %iv = phi i64 ...
  %cmp = icmp <pred> i64 %iv, sext/zext(%invariant)

In case if it is legal. Specifically, if `%iv` has signed comparison users, it is
required that `sext(trunc(%iv)) == %iv`, and if it has unsigned comparison
uses then we require `zext(trunc(%iv)) == %iv`. The current implementation
bails if `%trunc` has other uses than `icmp`, but in theory we can handle more
cases here (e.g. if the user of trunc is bitcast).

Differential Revision: https://reviews.llvm.org/D47928
Reviewed By: reames

llvm-svn: 335020
2018-06-19 04:48:34 +00:00
Xin Tong
54b4227f32 Revert "Simplify blockaddress usage before giving up in MergeBlockIntoPredecessor"
This reverts commit f976cf4cca0794267f28b54e468007fd476d37d9.

I am reverting this because it causes break in a few bots and its going
to take me sometime to look at this.

llvm-svn: 334993
2018-06-18 23:20:08 +00:00
Xin Tong
bfd8cfcb8d Simplify blockaddress usage before giving up in MergeBlockIntoPredecessor
Summary:
Simplify blockaddress usage before giving up in MergeBlockIntoPredecessor

This is a missing small optimization in MergeBlockIntoPredecessor.

This helps with one simplifycfg test which expects this case to be handled.

Reviewers: davide, spatel, brzycki, asbirlea

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D48284

llvm-svn: 334992
2018-06-18 22:59:13 +00:00
Bjorn Pettersson
428caf988b Re-apply "[DebugInfo] Check size of variable in ConvertDebugDeclareToDebugValue"
This is r334704 (which was reverted in r334732) with a fix for
types like x86_fp80. We need to use getTypeAllocSizeInBits and
not getTypeStoreSizeInBits to avoid dropping debug info for
such types.

Original commit msg:
> Summary:
> Do not convert a DbgDeclare to DbgValue if the store
> instruction only refer to a fragment of the variable
> described by the DbgDeclare.
>
> Problem was seen when for example having an alloca for an
> array or struct, and there were stores to individual elements.
> In the past we inserted a DbgValue intrinsics for each store,
> just as if the store wrote the whole variable.
>
> When handling store instructions we insert a DbgValue that
> indicates that the variable is "undefined", as we do not know
> which part of the variable that is updated by the store.
>
> When ConvertDebugDeclareToDebugValue is used with a load/phi
> instruction we assert that the referenced value is large enough
> to cover the whole variable. Afaict this should be true for all
> scenarios where those methods are used on trunk. If the assert
> blows in the future I guess we could simply skip to insert a
> dbg.value instruction.
>
> In the future I think we should examine which part of the variable
> that is accessed, and add a DbgValue instrinsic with an appropriate
> DW_OP_LLVM_fragment expression.
>
> Reviewers: dblaikie, aprantl, rnk
>
> Reviewed By: aprantl
>
> Subscribers: JDevlieghere, llvm-commits
>
> Tags: #debug-info
>
> Differential Revision: https://reviews.llvm.org/D48024

llvm-svn: 334830
2018-06-15 13:48:55 +00:00
Bjorn Pettersson
972fd1c9e7 Revert rL334704: "[DebugInfo] Check size of variable in ConvertDebugDeclareToDebugValue"
This reverts commit r334704.

Buildbots detected an assertion in "test tsan in debug compiler-rt build".

llvm-svn: 334732
2018-06-14 16:08:22 +00:00
Bjorn Pettersson
e406b29c22 [DebugInfo] Check size of variable in ConvertDebugDeclareToDebugValue
Summary:
Do not convert a DbgDeclare to DbgValue if the store
instruction only refer to a fragment of the variable
described by the DbgDeclare.

Problem was seen when for example having an alloca for an
array or struct, and there were stores to individual elements.
In the past we inserted a DbgValue intrinsics for each store,
just as if the store wrote the whole variable.

When handling store instructions we insert a DbgValue that
indicates that the variable is "undefined", as we do not know
which part of the variable that is updated by the store.

When ConvertDebugDeclareToDebugValue is used with a load/phi
instruction we assert that the referenced value is large enough
to cover the whole variable. Afaict this should be true for all
scenarios where those methods are used on trunk. If the assert
blows in the future I guess we could simply skip to insert a
dbg.value instruction.

In the future I think we should examine which part of the variable
that is accessed, and add a DbgValue instrinsic with an appropriate
DW_OP_LLVM_fragment expression.

Reviewers: dblaikie, aprantl, rnk

Reviewed By: aprantl

Subscribers: JDevlieghere, llvm-commits

Tags: #debug-info

Differential Revision: https://reviews.llvm.org/D48024

llvm-svn: 334704
2018-06-14 11:23:42 +00:00
Max Kazantsev
0ed79620c6 [SimplifyIndVars] Ignore dead users
IndVarSimplify sometimes makes transforms basing on users that are trivially dead. In particular,
if DCE wasn't run before it, there may be a dead `sext/zext` in loop that will trigger widening
transforms, however it makes no sense to do it.

This patch teaches IndVarsSimplify ignore the mist trivial cases of that.

Differential Revision: https://reviews.llvm.org/D47974
Reviewed By: sanjoy

llvm-svn: 334567
2018-06-13 02:25:32 +00:00
Florian Hahn
a1cc848399 Use SmallPtrSet explicitly for SmallSets with pointer types (NFC).
Currently SmallSet<PointerTy> inherits from SmallPtrSet<PointerTy>. This
patch replaces such types with SmallPtrSet, because IMO it is slightly
clearer and allows us to get rid of unnecessarily including SmallSet.h

Reviewers: dblaikie, craig.topper

Reviewed By: dblaikie

Differential Revision: https://reviews.llvm.org/D47836

llvm-svn: 334492
2018-06-12 11:16:56 +00:00
Craig Topper
61998289f9 Use SmallPtrSet instead of SmallSet in places where we iterate over the set.
SmallSet forwards to SmallPtrSet for pointer types. SmallPtrSet supports iteration, but a normal SmallSet doesn't. So if it wasn't for the forwarding, this wouldn't work.

These places were found by hiding the begin/end methods in the SmallSet forwarding

llvm-svn: 334343
2018-06-09 05:04:20 +00:00
Florian Hahn
0d6b01761c [Mem2Reg] Avoid replacing load with itself in promoteSingleBlockAlloca.
We do the same thing in rewriteSingleStoreAlloca.

Fixes PR37632.

Reviewers: chandlerc, davide, efriedma

Reviewed By: davide

Differential Revision: https://reviews.llvm.org/D47825

llvm-svn: 334187
2018-06-07 11:09:05 +00:00
Max Kazantsev
b4b2ccea6d [NFC] Use variable instead of accessing pair many times
llvm-svn: 334173
2018-06-07 08:47:19 +00:00
David Blaikie
31b98d2e99 Move Analysis/Utils/Local.h back to Transforms
Review feedback from r328165. Split out just the one function from the
file that's used by Analysis. (As chandlerc pointed out, the original
change only moved the header and not the implementation anyway - which
was fine for the one function that was used (since it's a
template/inlined in the header) but not in general)

llvm-svn: 333954
2018-06-04 21:23:21 +00:00
David Bolvansky
5430b73755 [SimplifyLibcalls] [NFC] Cleanup, improvements
Summary:
* Use "find('%')" instead of loop to find '%' char (we already uses find('%') in optimizePrintFString..)
* Convert getParent() chains to getModule()/getFunction()

Reviewers: lebedev.ri, spatel

Reviewed By: spatel

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D47397

llvm-svn: 333668
2018-05-31 16:39:27 +00:00
Chandler Carruth
4cbcbb0761 [LoopInstSimplify] Re-implement the core logic of loop-instsimplify to
be both simpler and substantially more efficient.

Rather than use a hand-rolled iteration technique that isn't quite the
same as RPO, use the pre-built RPO loop body traversal utility.

Once visiting the loop body in RPO, we can assert that we visit defs
before uses reliably. When this is the case, the only need to iterate is
when simplifying a def that is used by a PHI node along a back-edge.
With this patch, the first pass over the loop body is just a complete
simplification of every instruction across the loop body. When we
encounter a use of a simplified instruction that stems from a PHI node
in the loop body that has already been visited (due to some cyclic CFG,
potentially the loop itself, or a nested loop, or unstructured control
flow), we recall that specific PHI node for the second iteration.
Nothing else needs to be preserved from iteration to iteration.

On the second and later iterations, only instructions known to have
simplified inputs are considered, each time starting from a set of PHIs
that had simplified inputs along the backedges.

Dead instructions are collected along the way, but deleted in a batch at
the end of each iteration making the iterations themselves substantially
simpler. This uses a new batch API for recursively deleting dead
instructions.

This alsa changes the routine to visit subloops. Because simplification
is fundamentally transitive, we may need to visit the entire loop body,
including subloops, to handle knock-on simplification.

I've added a basic test file that helps demonstrate that all of these
changes work. It includes both straight-forward loops with
simplifications as well as interesting PHI-structures, CFG-structures,
and a nested loop case.

Differential Revision: https://reviews.llvm.org/D47407

llvm-svn: 333461
2018-05-29 20:15:38 +00:00
David Green
aee7ad0cde Revert 333358 as it's failing on some builders.
I'm guessing the tests reply on the ARM backend being built.

llvm-svn: 333359
2018-05-27 12:54:33 +00:00
David Green
3034281b43 [UnrollAndJam] Add a new Unroll and Jam pass
This is a simple implementation of the unroll-and-jam classical loop
optimisation.

The basic idea is that we take an outer loop of the form:

for i..
  ForeBlocks(i)
  for j..
    SubLoopBlocks(i, j)
  AftBlocks(i)

Instead of doing normal inner or outer unrolling, we unroll as follows:

for i... i+=2
  ForeBlocks(i)
  ForeBlocks(i+1)
  for j..
    SubLoopBlocks(i, j)
    SubLoopBlocks(i+1, j)
  AftBlocks(i)
  AftBlocks(i+1)
Remainder

So we have unrolled the outer loop, then jammed the two inner loops into
one. This can lead to a simpler inner loop if memory accesses can be shared
between the now-jammed loops.

To do this we have to prove that this is all safe, both for the memory
accesses (using dependence analysis) and that ForeBlocks(i+1) can move before
AftBlocks(i) and SubLoopBlocks(i, j).

Differential Revision: https://reviews.llvm.org/D41953

llvm-svn: 333358
2018-05-27 12:11:21 +00:00
Sanjay Patel
4b96935bd7 [InstCombine] use nsw negation for abs libcalls
Also, produce the canonical IR abs (s<0) to be more efficient. 

This is the libcall equivalent of the clang builtin change from:
rL333038

Pasting from that commit message:
The stdlib functions are defined in section 7.20.6.1 of the C standard with:
"If the result cannot be represented, the behavior is undefined."

That lets us mark the negation with 'nsw' because "sub i32 0, INT_MIN" would
be UB/poison.

llvm-svn: 333042
2018-05-22 23:29:40 +00:00
David Bolvansky
1f343fa0e0 [InstCombine] Remove calloc transformations
Summary: Previous patch does not care if a value is changed between calloc and strlen. This needs to be removed from InstCombine and maybe moved to DSE later after some rework.

Reviewers: efriedma

Reviewed By: efriedma

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D47218

llvm-svn: 333022
2018-05-22 20:27:36 +00:00
David Bolvansky
41f4b64ee1 [InstCombine] Calloc-ed strings optimizations
Summary:
Example cases:
strlen(calloc(...)) -> 0

Reviewers: efriedma, bkramer

Reviewed By: bkramer

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D47059

llvm-svn: 332990
2018-05-22 15:41:23 +00:00
Karl-Johan Karlsson
11d68a619e [LowerSwitch] Fixed faulty PHI node update
Summary:
When lowerswitch merge several cases into a new default block it's not
updating the PHI nodes accordingly. The code that update the PHI nodes
for the default edge only update the first entry and do not remove the
remaining ones, to make sure the number of entries match the number of
predecessors.

This is easily fixed by replacing the code that update the PHI node with
the already existing utility function for updating PHI nodes.

Reviewers: hans, reames, arsenm

Reviewed By: arsenm

Subscribers: wdng, llvm-commits

Differential Revision: https://reviews.llvm.org/D47055

llvm-svn: 332960
2018-05-22 08:46:48 +00:00
Bjorn Pettersson
fecef6be9e [LoopVersioning] Don't modify the list that we iterate over in addPHINodes
Summary:
In LoopVersioning::addPHINodes we need to iterate over all
users for a value "Inst", and if the user is outside of the
VersionedLoop we should replace the use of "Inst" by using
the value "PN" instead.

Replacing the use of "Inst" for a user of "Inst" also means
that Inst->users() is modified. So it is not safe to do the
replace while iterating over Inst->users() as we used to do.
This patch splits the task into two steps. First we iterate
over Inst->users() to find all users that should be updated.
Those users are saved into a local data structure on the stack.
And then, in the second step, we do the actual updates. This
time iterating over the local data structure.

Reviewers: mzolotukhin, anemet

Reviewed By: mzolotukhin

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D47134

llvm-svn: 332958
2018-05-22 08:33:02 +00:00
Yaxun Liu
ea988f1fd9 Fix evaluator for non-zero alloca addr space
The evaluator goes through BB and creates global vars as temporary values to evaluate
results of LLVM instructions. It creates undef for alloca, however it assumes alloca
in addr space 0. If the next instruction is addrspace cast to 0, then we get an invalid
cast instruction.

This patch let the temp global var have an address space matching alloca addr space,
so that the valuation can be done.

Differential Revision: https://reviews.llvm.org/D47081

llvm-svn: 332794
2018-05-19 02:58:16 +00:00
Piotr Padlewski
a26a08cb52 Constant fold launder of null and undef
Summary:
This might be useful because clang will add
some barriers for pointer comparisons.

Reviewers: majnemer, dberlin, hfinkel, nlewycky, davide, rsmith, amharc,
kuhar

Subscribers: davide, amharc, llvm-commits

Differential Revision: https://reviews.llvm.org/D32423

llvm-svn: 332786
2018-05-18 23:52:57 +00:00
David Stenberg
0af67e5b65 [SimplifyCFG] Fix a debug invariant bug in FoldBranchToCommonDest()
Summary:
Fix a case where FoldBranchToCommonDest() would bail out from doing CSE
when encountering a debug intrinsic. Handle that by skipping past the
debug intrinsics.

Also, as a minor refactoring, rename checkCSEInPredecessor() to
tryCSEWithPredecessor() to make it a bit more clear that the function
may remove instructions.

Reviewers: fhahn, craig.topper, dblaikie, xbolva00

Reviewed By: fhahn, xbolva00

Subscribers: vsk, davide, llvm-commits

Differential Revision: https://reviews.llvm.org/D46635

llvm-svn: 332698
2018-05-18 08:52:15 +00:00
Heejin Ahn
b4be38fcdd [WebAssembly] Add Wasm personality and isScopedEHPersonality()
Summary:
- Add wasm personality function
- Re-categorize the existing `isFuncletEHPersonality()` function into
two different functions: `isFuncletEHPersonality()` and
`isScopedEHPersonality(). This becomes necessary as wasm EH uses scoped
EH instructions (catchswitch, catchpad/ret, and cleanuppad/ret) but not
outlined funclets.
- Changed some callsites of `isFuncletEHPersonality()` to
`isScopedEHPersonality()` if they are related to scoped EH IR-level
stuff.

Reviewers: majnemer, dschuff, rnk

Subscribers: jfb, sbc100, jgravelle-google, eraman, JDevlieghere, sunfish, llvm-commits

Differential Revision: https://reviews.llvm.org/D45559

llvm-svn: 332667
2018-05-17 20:52:03 +00:00
Benjamin Kramer
8ac15bf4dc [InstCombine] Fix the signature of fgets_unlocked.
It returns a pointer, not an int. This miscompiles all code that uses
the return value of fgets.

llvm-svn: 332531
2018-05-16 21:45:39 +00:00
David Bolvansky
ca22d427b9 [SimplifyLibcalls] Replace locked IO with unlocked IO
Summary: If file stream arg is not captured and source is fopen, we could replace IO calls by unlocked IO ("_unlocked" function variants) to gain better speed,

Reviewers: efriedma, RKSimon, spatel, sanjoy, hfinkel, majnemer, lebedev.ri, rja

Reviewed By: rja

Subscribers: rja, srhines, efriedma, lebedev.ri, llvm-commits

Differential Revision: https://reviews.llvm.org/D45736

llvm-svn: 332452
2018-05-16 11:39:52 +00:00
David Green
cdee1d957e [LoopUnroll] Split out simplify code after Unroll into a new function. NFC
So that it can be shared with other passes that may end up doing the same
thing.

Differential Revision: https://reviews.llvm.org/D45874

llvm-svn: 332450
2018-05-16 10:41:58 +00:00
Nicola Zaghen
d34e60ca85 Rename DEBUG macro to LLVM_DEBUG.
The DEBUG() macro is very generic so it might clash with other projects.
The renaming was done as follows:
- git grep -l 'DEBUG' | xargs sed -i 's/\bDEBUG\s\?(/LLVM_DEBUG(/g'
- git diff -U0 master | ../clang/tools/clang-format/clang-format-diff.py -i -p1 -style LLVM
- Manual change to APInt
- Manually chage DOCS as regex doesn't match it.

In the transition period the DEBUG() macro is still present and aliased
to the LLVM_DEBUG() one.

Differential Revision: https://reviews.llvm.org/D43624

llvm-svn: 332240
2018-05-14 12:53:11 +00:00
Nicola Zaghen
617d4a8199 Test commit access.
Remove trailing whitespace.

llvm-svn: 332220
2018-05-14 08:24:29 +00:00
Sergey Dmitriev
69c9cd277d [CodeExtractor] Allow extracting blocks with exception handling
This is a CodeExtractor improvement which adds support for extracting blocks
which have exception handling constructs if that is legal to do. CodeExtractor
performs validation checks to ensure that extraction is legal when it finds
invoke instructions or EH pads (landingpad, catchswitch, or cleanuppad) in
blocks to be extracted.

I have also added an option to allow extraction of blocks with alloca
instructions, but no validation is done for allocas. CodeExtractor caller has
to validate it himself before allowing alloca instructions to be extracted.
By default allocas are still not allowed in extraction blocks.

Differential Revision: https://reviews.llvm.org/D45904

llvm-svn: 332151
2018-05-11 22:49:49 +00:00
David Bolvansky
cd93c4ef1a [InstCombine] snprintf optimizations
Reviewers: spatel, efriedma, majnemer, rja, bkramer

Reviewed By: rja, bkramer

Subscribers: mstorsjo, rja, llvm-commits

Differential Revision: https://reviews.llvm.org/D46285

llvm-svn: 332110
2018-05-11 17:50:49 +00:00
Vedant Kumar
e0b5f86b30 [STLExtras] Add distance() for ranges, pred_size(), and succ_size()
This commit adds a wrapper for std::distance() which works with ranges.
As it would be a common case to write `distance(predecessors(BB))`, this
also introduces `pred_size()` and `succ_size()` helpers to make that
easier to write.

Differential Revision: https://reviews.llvm.org/D46668

llvm-svn: 332057
2018-05-10 23:01:54 +00:00
Martin Storsjo
86e6742c17 Revert "[InstCombine] snprintf optimizations"
This reverts commit SVN r331889, which could trigger failed
assertions for cases where the snprintf function is declared
with a vaguely differing signature (e.g. being defined as
static inline), see PR37408.

llvm-svn: 332043
2018-05-10 21:23:36 +00:00
whitequark
68403564df [PR37339] Fix assertion in FunctionComparator::cmpInlineAsm
Fixes bug https://bugs.llvm.org/show_bug.cgi?id=37339.

InlineAsm is only uniqued if the FunctionTypes are exactly the
same, while cmpTypes() for example considers all pointer types
in the default address space to be the same. For this reason
the end of cmpInlineAsm() can be reached.

This patch replaces the unreachable assertion with a check that
the function types are not identical.

Differential Revision: https://reviews.llvm.org/D46495

Reviewers: jfb
llvm-svn: 331990
2018-05-10 15:05:47 +00:00
David Bolvansky
9b5e6e8288 [InstCombine] snprintf optimizations
Reviewers: spatel, efriedma, majnemer, rja, bkramer

Reviewed By: rja, bkramer

Subscribers: rja, llvm-commits

Differential Revision: https://reviews.llvm.org/D46285

llvm-svn: 331889
2018-05-09 16:09:31 +00:00
Benjamin Kramer
ccb0fbe9a0 Revert "[InstCombine] snprintf optimizations"
This reverts commit r331849. It miscompiles
snprintf(buf, sizeof(buf), "%s", "any constant string); into
memcpy(buf, "%s", sizeof("any constant string"));

llvm-svn: 331866
2018-05-09 11:38:57 +00:00
David Bolvansky
44a37f04b2 [InstCombine] snprintf optimizations
Reviewers: spatel, efriedma, majnemer, rja

Reviewed By: rja

Subscribers: rja, llvm-commits

Differential Revision: https://reviews.llvm.org/D46285

llvm-svn: 331849
2018-05-09 06:34:20 +00:00
Shiva Chen
2c864551df [DebugInfo] Add DILabel metadata and intrinsic llvm.dbg.label.
In order to set breakpoints on labels and list source code around
labels, we need collect debug information for labels, i.e., label
name, the function label belong, line number in the file, and the
address label located. In order to keep these information in LLVM
IR and to allow backend to generate debug information correctly.
We create a new kind of metadata for labels, DILabel. The format
of DILabel is

!DILabel(scope: !1, name: "foo", file: !2, line: 3)

We hope to keep debug information as much as possible even the
code is optimized. So, we create a new kind of intrinsic for label
metadata to avoid the metadata is eliminated with basic block.
The intrinsic will keep existing if we keep it from optimized out.
The format of the intrinsic is

llvm.dbg.label(metadata !1)

It has only one argument, that is the DILabel metadata. The
intrinsic will follow the label immediately. Backend could get the
label metadata through the intrinsic's parameter.

We also create DIBuilder API for labels to be used by Frontend.
Frontend could use createLabel() to allocate DILabel objects, and use
insertLabel() to insert llvm.dbg.label intrinsic in LLVM IR.

Differential Revision: https://reviews.llvm.org/D45024

Patch by Hsiangkai Wang.

llvm-svn: 331841
2018-05-09 02:40:45 +00:00
Heejin Ahn
bf7716952a Support a funclet operand bundle in LowerInvoke
Summary:
The current LowerInvoke pass cannot handle invoke instructions with a
funclet bundle operand. The order of operands for an invoke instruction
is {call arguments, callee, funclet operand (if any), normal dest,
unwind dest}. The current code assumes there is no funclet operand and
incorrectly includes a funclet operand into call arguments.

Reviewers: rnk

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D46242

llvm-svn: 331832
2018-05-09 00:53:50 +00:00
Davide Italiano
48283ba3a1 [SimplifyCFG] Fix a crash when folding PHIs.
We enter MergeBlockIntoPredecessor with a block looking like this:

for.inc.us-lcssa:                                 ; preds = %cond.end
  %k.1.lcssa.ph = phi i32 [ %conv15, %cond.end ]
  %t.3.lcssa.ph = phi i32 [ %k.1.lcssa.ph, %cond.end ]
  br label %for.inc, !dbg !66

[note the first arg of the PHI being a PHI].
FoldSingleEntryPHINodes gets rid of both PHIs (calling, eraseFromParent).
But right before we call the function, we push into IncomingValues the
only argument of the PHIs, and shortly after we try to iterate over
something which has been invalidated before :(

The fix its not trying to remove PHIs which have an incoming value
coming from the same BB we're looking at.

Fixes PR37300 and rdar://problem/39910460

Differential Revision:  https://reviews.llvm.org/D46568

llvm-svn: 331824
2018-05-08 23:28:15 +00:00
Bjorn Pettersson
51cebc98f3 [LCSSA] Do not remove used PHI nodes in formLCSSAForInstructions
Summary:
In formLCSSAForInstructions we speculatively add new PHI
nodes, that sometimes ends up without having any uses. It
has been discovered that sometimes an added PHI node can
appear as being unused in one iteration of the Worklist,
although it can end up being used by a PHI node added in
a later iteration. We now check, a second time, that the
PHI node still is unused before we remove it. This avoids
an assert about "Trying to remove a phi with uses." for the
added test case.

Reviewers: davide, mzolotukhin, mattd, dberlin

Reviewed By: mzolotukhin, dberlin

Subscribers: dberlin, mzolotukhin, davide, bjope, uabelho, llvm-commits

Differential Revision: https://reviews.llvm.org/D46422

llvm-svn: 331741
2018-05-08 06:59:47 +00:00
Fangrui Song
862eebb6d6 Simplify LLVM_ATTRIBUTE_USED call sites.
llvm-svn: 331599
2018-05-05 20:14:38 +00:00
George Burgess IV
f9d26af4ea Range-ify for loop; NFC
llvm-svn: 331582
2018-05-05 04:52:26 +00:00
Craig Topper
781aa181ab Fix a bunch of places where operator-> was used directly on the return from dyn_cast.
Inspired by r331508, I did a grep and found these.

Mostly just change from dyn_cast to cast. Some cases also showed a dyn_cast result being converted to bool, so those I changed to isa.

llvm-svn: 331577
2018-05-05 01:57:00 +00:00
Adrian Prantl
4dfcc4a788 Remove @brief commands from doxygen comments, too.
This is a follow-up to r331272.

We've been running doxygen with the autobrief option for a couple of
years now. This makes the \brief markers into our comments
redundant. Since they are a visual distraction and we don't want to
encourage more \brief markers in new code either, this patch removes
them all.

Patch produced by
  for i in $(git grep -l '\@brief'); do perl -pi -e 's/\@brief //g' $i & done

https://reviews.llvm.org/D46290

llvm-svn: 331275
2018-05-01 16:10:38 +00:00
Adrian Prantl
5f8f34e459 Remove \brief commands from doxygen comments.
We've been running doxygen with the autobrief option for a couple of
years now. This makes the \brief markers into our comments
redundant. Since they are a visual distraction and we don't want to
encourage more \brief markers in new code either, this patch removes
them all.

Patch produced by

  for i in $(git grep -l '\\brief'); do perl -pi -e 's/\\brief //g' $i & done

Differential Revision: https://reviews.llvm.org/D46290

llvm-svn: 331272
2018-05-01 15:54:18 +00:00
Florian Hahn
3df8844b92 [SimplifyCFG] Use BB::instructionsWithoutDebug to skip DbgInfo (NFC).
This patch updates some code responsible the skip debug info to use
BasicBlock::instructionsWithoutDebug. I think this makes things slightly
simpler and more direct.

Reviewers: aprantl, vsk, hans, danielcdh

Reviewed By: hans

Differential Revision: https://reviews.llvm.org/D46252

llvm-svn: 331221
2018-04-30 20:10:53 +00:00
Florian Hahn
8fe04ad3f7 [LoopSimplify] Use BB::instructionsWithoutDebug to skip DbgInfo (NFC).
This patch updates some code responsible the skip debug info to use
BasicBlock::instructionsWithoutDebug. I think this makes things slightly
simpler and more direct.

Reviewers: aprantl, vsk, chandlerc

Reviewed By: aprantl

Differential Revision: https://reviews.llvm.org/D46253

llvm-svn: 331217
2018-04-30 19:19:36 +00:00
Adrian Prantl
210a29de7b Fix a bug in GlobalOpt's handling of DIExpressions.
This patch adds support for fragment expressions
TryToShrinkGlobalToBoolean() which were previously just dropped.

Thanks to Reid Kleckner for providing me a reproducer!

llvm-svn: 331086
2018-04-27 21:41:36 +00:00