Commit Graph

246 Commits

Author SHA1 Message Date
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
Nicola Zaghen 617d4a8199 Test commit access.
Remove trailing whitespace.

llvm-svn: 332220
2018-05-14 08:24:29 +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
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
Roman Tereshin dab10b5468 [DebugInfo][OPT] NFC follow-up on "Fixing a couple of DI duplication bugs of CloneModule"
llvm-svn: 330070
2018-04-13 21:23:11 +00:00
Roman Tereshin d769eb36ab [DebugInfo][OPT] Fixing a couple of DI duplication bugs of CloneModule
As demonstrated by the regression tests added in this patch, the
following cases are valid cases:

1. A Function with no DISubprogram attached, but various debug info
  related to its instructions, coming, for instance, from an inlined
  function, also defined somewhere else in the same module;
2. ... or coming exclusively from the functions inlined and eliminated
  from the module entirely.

The ValueMap shared between CloneFunctionInto calls within CloneModule
needs to contain identity mappings for all of the DISubprogram's to
prevent them from being duplicated by MapMetadata / RemapInstruction
calls, this is achieved via DebugInfoFinder collecting all the
DISubprogram's. However, CloneFunctionInto was missing calls into
DebugInfoFinder for functions w/o DISubprogram's attached, but still
referring DISubprogram's from within (case 1). This patch fixes that.

The fix above, however, exposes another issue: if a module contains a
DISubprogram referenced only indirectly from other debug info
metadata, but not attached to any Function defined within the module
(case 2), cloning such a module causes a DICompileUnit duplication: it
will be moved in indirecty via a DISubprogram by DebugInfoFinder first
(because of the first bug fix described above), without being
self-mapped within the shared ValueMap, and then will be copied during
named metadata cloning. So this patch makes sure DebugInfoFinder
visits DICompileUnit's referenced from DISubprogram's as it goes w/o
re-processing llvm.dbg.cu list over and over again for every function
cloned, and makes sure that CloneFunctionInto self-maps
DICompileUnit's referenced from the entire function, not just its own
DISubprogram attached that may also be missing.

The most convenient way of tesing CloneModule I found is to rely on
CloneModule call from `opt -run-twice`, instead of writing tedious
unit tests. That feature has a couple of properties that makes it hard
to use for this purpose though:

1. CloneModule doesn't copy source filename, making `opt -run-twice`
  report it as a difference.
2. `opt -run-twice` does the second run on the original module, not
  its clone, making the result of cloning completely invisible in opt's
  actual output with and without `-run-twice` both, which directly
  contradicts `opt -run-twice`s own error message.

This patch fixes this as well.

Reviewed By: aprantl

Reviewers: loladiro, GorNishanov, espindola, echristo, dexonsmith

Subscribers: vsk, debug-info, JDevlieghere, llvm-commits

Differential Revision: https://reviews.llvm.org/D45593

llvm-svn: 330069
2018-04-13 21:22:24 +00:00
Florian Hahn 3bb822e7d6 [CloneFunction] Preserve DT in DuplicateInstructionsInSplitBetween.
DuplicateInstructionsInSplitBetween can preserve the DT by passing
through DT to SplitEdge.

Reviewers: sanjoy, junbuml, anna, kuhar

Reviewed By: kuhar

Differential Revision: https://reviews.llvm.org/D44629

llvm-svn: 328189
2018-03-22 11:38:53 +00:00
David Blaikie 2be3922807 Fix a couple of layering violations in Transforms
Remove #include of Transforms/Scalar.h from Transform/Utils to fix layering.

Transforms depends on Transforms/Utils, not the other way around. So
remove the header and the "createStripGCRelocatesPass" function
declaration (& definition) that is unused and motivated this dependency.

Move Transforms/Utils/Local.h into Analysis because it's used by
Analysis/MemoryBuiltins.cpp.

llvm-svn: 328165
2018-03-21 22:34:23 +00:00
Florian Hahn f0a25f7253 [CloneFunction] Support BB == PredBB in DuplicateInstructionsInSplit.
In case PredBB == BB and StopAt == BB's terminator, StopAt != &*BI will
fail, because BB's terminator instruction gets replaced.

By using BB.getTerminator() we get the current terminator which we can use
to compare.

Reviewers: sanjoy, anna, reames

Reviewed By: anna

Differential Revision: https://reviews.llvm.org/D43822

llvm-svn: 326779
2018-03-06 13:12:32 +00:00
Benjamin Kramer c7fc81e659 Use phi ranges to simplify code. No functionality change intended.
llvm-svn: 321585
2017-12-30 15:27:33 +00:00
Sanjoy Das def1729dc4 Use a BumpPtrAllocator for Loop objects
Summary:
And now that we no longer have to explicitly free() the Loop instances, we can
(with more ease) use the destructor of LoopBase to do what LoopBase::clear() was
doing.

Reviewers: chandlerc

Subscribers: mehdi_amini, mcrosier, llvm-commits

Differential Revision: https://reviews.llvm.org/D38201

llvm-svn: 314375
2017-09-28 02:45:42 +00:00
Chandler Carruth 4f3aa29a46 [Inliner] Fix a nasty bug when inlining a non-recursive trace of
a function into itself.

We tried to fix this before in r306495 but that got reverted as the
assert was actually hit.

This fixes the original bug (which we seem to have lost track of with
the revert) by blocking a second remapping when the function being
inlined is also the caller and the remapping could succeed but
erroneously.

The included test case would actually load from an inlined copy of the
alloca before this change, failing to load the stored value and
miscompiling.

Many thanks to Richard Smith for diagnosing a user miscompile to this
bug, and to Kyle for the first attempt and initial analysis and David Li
for remembering the issue and how to fix it and suggesting the patch.
I'm just stitching it together and landing it. =]

llvm-svn: 311229
2017-08-19 06:56:11 +00:00
Gor Nishanov 8cdf648795 [cloning] Do not duplicate types when cloning functions
Summary:
This is an addon to the change rl304488 cloning fixes. (Originally rl304226 reverted rl304228 and reapplied rl304488 https://reviews.llvm.org/D33655)

rl304488 works great when DILocalVariables that comes from the inlined function has a 'unique-ed' type, but,
in the case when the variable type is distinct we will create a second DILocalVariable in the scope of the original function that was inlined.

Consider cloning of the following function:
```
define private void @f() !dbg !5 {
  %1 = alloca i32, !dbg !11
  call void @llvm.dbg.declare(metadata i32* %1, metadata !14, metadata !12), !dbg !18
  ret void, !dbg !18
}

!14 = !DILocalVariable(name: "inlined", scope: !15, file: !6, line: 5, type: !17) ; came from an inlined function
!15 = distinct !DISubprogram(name: "inlined", linkageName: "inlined", scope: null, file: !6, line: 8, type: !7, isLocal: true, isDefinition: true, scopeLine: 9, isOptimized: false, unit: !0, variables: !16)
!16 = !{!14}
!17 = distinct !DICompositeType(tag: DW_TAG_structure_type, name: "some_struct", size: 32, align: 32)
```

Without this fix, when function 'f' is cloned, we will create another DILocalVariable for "inlined", due to its type being distinct.

```
define private void @f.1() !dbg !23 {
  %1 = alloca i32, !dbg !26
  call void @llvm.dbg.declare(metadata i32* %1, metadata !28, metadata !12), !dbg !30
  ret void, !dbg !30
}

!14 = !DILocalVariable(name: "inlined", scope: !15, file: !6, line: 5, type: !17)
!15 = distinct !DISubprogram(name: "inlined", linkageName: "inlined", scope: null, file: !6, line: 8, type: !7, isLocal: true, isDefinition: true, scopeLine: 9, isOptimized: false, unit: !0, variables: !16)
!16 = !{!14}
!17 = distinct !DICompositeType(tag: DW_TAG_structure_type, name: "some_struct", size: 32, align: 32)
 ;
!28 = !DILocalVariable(name: "inlined", scope: !15, file: !6, line: 5, type: !29) ; OOPS second DILocalVariable
!29 = distinct !DICompositeType(tag: DW_TAG_structure_type, name: "some_struct", size: 32, align: 32)
```

Now we have two DILocalVariable for "inlined" within the same scope. This result in assert in AsmPrinter/DwarfDebug.h:131: void llvm::DbgVariable::addMMIEntry(const llvm::DbgVariable &): Assertion `V.Var == Var && "conflicting variable"' failed.
(Full example: See: https://bugs.llvm.org/show_bug.cgi?id=33492)

In this change we prevent duplication of types so that when a metadata for DILocalVariable is cloned it will get uniqued to the same metadate node as an original variable.

Reviewers: loladiro, dblaikie, aprantl, echristo

Reviewed By: loladiro

Subscribers: EricWF, llvm-commits

Differential Revision: https://reviews.llvm.org/D35106

llvm-svn: 307418
2017-07-07 18:24:20 +00:00
Davide Italiano 9282f1aece [Cloner] Re-map simplfied cloned instructions.
This commit pretty much rolls back the logic added in r306495
as in the testcase provided we simplify an `icmp` looking through
a PHI that hasn't been mapped yet.

I think instsimplify shouldn't do threading over select/phis or
just looking through phis in general, but this is what we have
now. Also, add a test to prevent this from happening in case somebody
wants to modify this code again.

Briefly discussed with Kyle Butt (thanks Kyle!).

llvm-svn: 306938
2017-07-01 03:29:33 +00:00
Kyle Butt f73c8a06a9 Inlining: Don't re-map simplified cloned instructions.
When simplifying an instruction that has been re-mapped, it should never
simplify to an instruction in the original function. In the edge case
where we are inlining a function into itself, the existing code led to
incorrect behavior. Replace the incorrect code with an assert verifying
that we never expect simplification to produce an instruction in the old
function, unless the functions are the same.

Differential Revision: https://reviews.llvm.org/D33850

llvm-svn: 306495
2017-06-28 01:41:25 +00:00
Chandler Carruth 6bda14b313 Sort the remaining #include lines in include/... and lib/....
I did this a long time ago with a janky python script, but now
clang-format has built-in support for this. I fed clang-format every
line with a #include and let it re-sort things according to the precise
LLVM rules for include ordering baked into clang-format these days.

I've reverted a number of files where the results of sorting includes
isn't healthy. Either places where we have legacy code relying on
particular include ordering (where possible, I'll fix these separately)
or where we have particular formatting around #include lines that
I didn't want to disturb in this patch.

This patch is *entirely* mechanical. If you get merge conflicts or
anything, just ignore the changes in this patch and run clang-format
over your #include lines in the files.

Sorry for any noise here, but it is important to keep these things
stable. I was seeing an increasing number of patches with irrelevant
re-ordering of #include lines because clang-format was used. This patch
at least isolates that churn, makes it easy to skip when resolving
conflicts, and gets us to a clean baseline (again).

llvm-svn: 304787
2017-06-06 11:49:48 +00:00
Keno Fischer fa635d730f Reapply "[Cloning] Take another pass at properly cloning debug info"
This was rL304226, reverted in 304228 due to a clang assertion failure
on the build bots. That problem should have been addressed by clang
commit rL304470.

llvm-svn: 304488
2017-06-01 23:02:12 +00:00
Keno Fischer 3fa5db4c04 Revert "[Cloning] Take another pass at properly cloning debug info"
At least one build bot is complaining. Will investigate after lunch.

llvm-svn: 304228
2017-05-30 18:56:26 +00:00
Keno Fischer 945dc1d2d1 [Cloning] Take another pass at properly cloning debug info
Summary:
In rL302576, DISubprograms gained the constraint that a !dbg attachments to functions must
have a 1:1 mapping to DISubprograms. As part of that change, the function cloning support
was adjusted to attempt to enforce this invariant during cloning. However, there
were several problems with the implementation. Part of these were fixed in rL304079.
However, there was a more fundamental problem with these changes, namely that it
bypasses the matadata value map, causing the cloned metadata to be a mix of metadata
pointing to the new suprogram (where manual code was added to fix those up) and the
old suprogram (where this was not the case). This mismatch could cause a number of
different assertion failures in the DWARF emitter. Some of these are given at
https://github.com/JuliaLang/julia/issues/22069, but some others have been observed
as well. Attempt to rectify this by partially reverting the manual DI metadata fixup,
and instead using the standard value map approach. To retain the desired semantics
of not duplicating the compilation unit and inlined subprograms, explicitly freeze
these in the value map.

Reviewers: dblaikie, aprantl, GorNishanov, echristo

Reviewed By: aprantl

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D33655

llvm-svn: 304226
2017-05-30 18:28:30 +00:00
Gor Nishanov ffbeb22b6f Cloning: Fix debug info cloning
Summary:
I believe https://reviews.llvm.org/rL302576 introduced two bugs:

1) it produces duplicate distinct variables for every: dbg.value describing the same variable.
    To fix the problme I switched form getDistinct() to get() in DebugLoc.cpp: auto reparentVar = [&](DILocalVariable *Var) {
    return DILocalVariable::getDistinct(

2) It passes NewFunction plain name as a linkagename parameter to Subprogram constructor. Breaks assert in:

 || DeclLinkageName.empty()) || LinkageName == DeclLinkageName) && "decl has a linkage name and it is different"' failed.
#9 0x00007f5010261b75 llvm::DwarfUnit::applySubprogramDefinitionAttributes(llvm::DISubprogram const*, llvm::DIE&) /home/gor/llvm/lib/CodeGen/AsmPrinter/DwarfUnit.cpp:1173:3
#
(Edit: reproducer added)

Here how https://reviews.llvm.org/rL302576 broke coroutine debug info.
Coroutine body of the original function is split into several parts by cloning and removing unneeded code.
All parts describe the original function and variables present in the original function.

For a simple case, prior to Split, original function has these two blocks:

```
PostSpill:                                        ; preds = %AllocaSpillBB
  call void @llvm.dbg.value(metadata i32 %x, i64 0, metadata !14, metadata !15), !dbg !13
  store i32 %x, i32* %x.addr, align 4
  ...
and

sw.epilog:                                        ; preds = %sw.bb
  %x.addr.reload.addr = getelementptr inbounds %f.Frame, %f.Frame* %FramePtr, i32 0, i32 4, !dbg !20
  %4 = load i32, i32* %x.addr.reload.addr, align 4, !dbg !20
  call void @llvm.dbg.value(metadata i32 %4, i64 0, metadata !14, metadata !15), !dbg !13

!14 = !DILocalVariable(name: "x", arg: 1, scope: !6, file: !7, line: 55, type: !11)

```

Note that in two blocks different expression represent the same original user variable X.

Before rL302576, for every cloned function there was exactly one cloned DILocalVariable(name: "x" as in:

```
define i8* @f(i32 %x) #0 !dbg !6 {
  ...
!6 = distinct !DISubprogram(name: "f", scope: !7, file: !7, line: 55, type: !8, isLocal: false, isDefinition: true, scopeLine: 55, flags: DIFlagPrototyped,
...
!14 = !DILocalVariable(name: "x", arg: 1, scope: !6, file: !7, line: 55, type: !11)

define internal fastcc void @f.resume(%f.Frame* %FramePtr) #0 !dbg !25 {
...
!25 = distinct !DISubprogram(name: "f", scope: !7, file: !7, line: 55, type: !8, isLocal: false, isDefinition: true, scopeLine: 55, flags: DIFlagPrototyped, isOptimized: false, unit: !0, variables: !2)
!28 = !DILocalVariable(name: "x", arg: 1, scope: !25, file: !7, line: 55, type: !11)
```
After rL302576, for every cloned function there were as many DILocalVariable(name: "x" as there were "call void @llvm.dbg.value" for that variable.
This was causing asserts in VerifyDebugInfo and AssemblyPrinter.

Example:

```
!27 = distinct !DISubprogram(name: "f", linkageName: "f.resume", scope: !7, file: !7, line: 55, type: !8, isLocal: false, isDefinition: true, scopeLine: 55,
!29 = distinct !DILocalVariable(name: "x", arg: 1, scope: !27, file: !7, line: 55, type: !11)
!39 = distinct !DILocalVariable(name: "x", arg: 1, scope: !27, file: !7, line: 55, type: !11)
!41 = distinct !DILocalVariable(name: "x", arg: 1, scope: !27, file: !7, line: 55, type: !11)
```

Second problem:

Prior to rL302576, all clones were described by DISubprogram referring to original function.

```
define i8* @f(i32 %x) #0 !dbg !6 {
...
!6 = distinct !DISubprogram(name: "f", scope: !7, file: !7, line: 55, type: !8, isLocal: false, isDefinition: true, scopeLine: 55, flags: DIFlagPrototyped,

define internal fastcc void @f.resume(%f.Frame* %FramePtr) #0 !dbg !25 {
...
!25 = distinct !DISubprogram(name: "f", scope: !7, file: !7, line: 55, type: !8, isLocal: false, isDefinition: true, scopeLine: 55, flags: DIFlagPrototyped,
```

After rL302576, DISubprogram for clones is of two minds, plain name refers to the original name, linkageName refers to plain name of the clone.

```
!27 = distinct !DISubprogram(name: "f", linkageName: "f.resume", scope: !7, file: !7, line: 55, type: !8, isLocal: false, isDefinition: true, scopeLine: 55,
```

I think the assumption in AsmPrinter is that both name and linkageName should refer to the same entity. It asserts here when they are not:

```
 || DeclLinkageName.empty()) || LinkageName == DeclLinkageName) && "decl has a linkage name and it is different"' failed.
#9 0x00007f5010261b75 llvm::DwarfUnit::applySubprogramDefinitionAttributes(llvm::DISubprogram const*, llvm::DIE&) /home/gor/llvm/lib/CodeGen/AsmPrinter/DwarfUnit.cpp:1173:3
```
After this fix, behavior (with respect to coroutines) reverts to exactly as it was before and therefore making them debuggable again, or even more importantly, compilable, with "-g"

Reviewers: dblaikie, echristo, aprantl

Reviewed By: dblaikie

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D33614

llvm-svn: 304079
2017-05-27 19:41:09 +00:00
Reid Kleckner 96ab8726a3 [IR] De-virtualize ~Value to save a vptr
Summary:
Implements PR889

Removing the virtual table pointer from Value saves 1% of RSS when doing
LTO of llc on Linux. The impact on time was positive, but too noisy to
conclusively say that performance improved. Here is a link to the
spreadsheet with the original data:

https://docs.google.com/spreadsheets/d/1F4FHir0qYnV0MEp2sYYp_BuvnJgWlWPhWOwZ6LbW7W4/edit?usp=sharing

This change makes it invalid to directly delete a Value, User, or
Instruction pointer. Instead, such code can be rewritten to a null check
and a call Value::deleteValue(). Value objects tend to have their
lifetimes managed through iplist, so for the most part, this isn't a big
deal.  However, there are some places where LLVM deletes values, and
those places had to be migrated to deleteValue.  I have also created
llvm::unique_value, which has a custom deleter, so it can be used in
place of std::unique_ptr<Value>.

I had to add the "DerivedUser" Deleter escape hatch for MemorySSA, which
derives from User outside of lib/IR. Code in IR cannot include MemorySSA
headers or call the MemoryAccess object destructors without introducing
a circular dependency, so we need some level of indirection.
Unfortunately, no class derived from User may have any virtual methods,
because adding a virtual method would break User::getHungOffOperands(),
which assumes that it can find the use list immediately prior to the
User object. I've added a static_assert to the appropriate OperandTraits
templates to help people avoid this trap.

Reviewers: chandlerc, mehdi_amini, pete, dberlin, george.burgess.iv

Reviewed By: chandlerc

Subscribers: krytarowski, eraman, george.burgess.iv, mzolotukhin, Prazek, nlewycky, hans, inglorion, pcc, tejohnson, dberlin, llvm-commits

Differential Revision: https://reviews.llvm.org/D31261

llvm-svn: 303362
2017-05-18 17:24:10 +00:00
Adrian Prantl c10d0e5ccd Make it illegal for two Functions to point to the same DISubprogram
As recently discussed on llvm-dev [1], this patch makes it illegal for
two Functions to point to the same DISubprogram and updates
FunctionCloner to also clone the debug info of a function to conform
to the new requirement. To simplify the implementation it also factors
out the creation of inlineAt locations from the Inliner into a
general-purpose utility in DILocation.

[1] http://lists.llvm.org/pipermail/llvm-dev/2017-May/112661.html
<rdar://problem/31926379>

Differential Revision: https://reviews.llvm.org/D32975

This reapplies r302469 with a fix for a bot failure (reparentDebugInfo
now checks for the case the orig and new function are identical).

llvm-svn: 302576
2017-05-09 19:47:37 +00:00
Hans Wennborg 66fb0d9768 Revert r302469 "Make it illegal for two Functions to point to the same DISubprogram"
This caused PR32977.

Original commit message:

> Make it illegal for two Functions to point to the same DISubprogram
>
> As recently discussed on llvm-dev [1], this patch makes it illegal for
> two Functions to point to the same DISubprogram and updates
> FunctionCloner to also clone the debug info of a function to conform
> to the new requirement. To simplify the implementation it also factors
> out the creation of inlineAt locations from the Inliner into a
> general-purpose utility in DILocation.
>
> [1] http://lists.llvm.org/pipermail/llvm-dev/2017-May/112661.html
> <rdar://problem/31926379>
>
> Differential Revision: https://reviews.llvm.org/D32975

llvm-svn: 302533
2017-05-09 14:44:15 +00:00
Adrian Prantl 200a5ef526 Make it illegal for two Functions to point to the same DISubprogram
As recently discussed on llvm-dev [1], this patch makes it illegal for
two Functions to point to the same DISubprogram and updates
FunctionCloner to also clone the debug info of a function to conform
to the new requirement. To simplify the implementation it also factors
out the creation of inlineAt locations from the Inliner into a
general-purpose utility in DILocation.

[1] http://lists.llvm.org/pipermail/llvm-dev/2017-May/112661.html
<rdar://problem/31926379>

Differential Revision: https://reviews.llvm.org/D32975

llvm-svn: 302469
2017-05-08 21:17:08 +00:00
Sanjoy Das e6bca0eecb Rename WeakVH to WeakTrackingVH; NFC
This relands r301424.

llvm-svn: 301812
2017-05-01 17:07:49 +00:00
Sanjoy Das 2cbeb00f38 Reverts commit r301424, r301425 and r301426
Commits were:

"Use WeakVH instead of WeakTrackingVH in AliasSetTracker's UnkownInsts"
"Add a new WeakVH value handle; NFC"
"Rename WeakVH to WeakTrackingVH; NFC"

The changes assumed pointers are 8 byte aligned on all architectures.

llvm-svn: 301429
2017-04-26 16:37:05 +00:00
Sanjoy Das 01de557738 Rename WeakVH to WeakTrackingVH; NFC
Summary:
I plan to use WeakVH to mean "nulls itself out on deletion, but does
not track RAUW" in a subsequent commit.

Reviewers: dblaikie, davide

Reviewed By: davide

Subscribers: arsenm, mehdi_amini, mcrosier, mzolotukhin, jfb, llvm-commits, nhaehnle

Differential Revision: https://reviews.llvm.org/D32266

llvm-svn: 301424
2017-04-26 16:20:52 +00:00
Reid Kleckner f021fab2af [IR] Make getParamAttributes take argument numbers, not ArgNo+1
Add hasParamAttribute() and use it instead of hasAttribute(ArgNo+1,
Kind) everywhere.

The fact that the AttributeList index for an argument is ArgNo+1 should
be a hidden implementation detail.

NFC

llvm-svn: 300272
2017-04-13 23:12:13 +00:00
Reid Kleckner 7f72033e1c [IR] Take func, ret, and arg attrs separately in AttributeList::get
This seems like a much more natural API, based on Derek Schuff's
comments on r300015. It further hides the implementation detail of
AttributeList that function attributes come last and appear at index
~0U, which is easy for the user to screw up. git diff says it saves code
as well: 97 insertions(+), 137 deletions(-)

This also makes it easier to change the implementation, which I want to
do next.

llvm-svn: 300153
2017-04-13 00:58:09 +00:00
Chandler Carruth 927d8e610a [IR] Redesign the case iterator in SwitchInst to actually be an iterator
and to expose a handle to represent the actual case rather than having
the iterator return a reference to itself.

All of this allows the iterator to be used with common STL facilities,
standard algorithms, etc.

Doing this exposed some missing facilities in the iterator facade that
I've fixed and required some work to the actual iterator to fully
support the necessary API.

Differential Revision: https://reviews.llvm.org/D31548

llvm-svn: 300032
2017-04-12 07:27:28 +00:00
Reid Kleckner c2cb560045 [IR] Add AttributeSet to hide AttributeSetNode* again, NFC
Summary:
For now, it just wraps AttributeSetNode*. Eventually, it will hold
AvailableAttrs as an inline bitset, and adding and removing enum
attributes will be super cheap.

This sinks AttributeSetNode back down to lib/IR/AttributeImpl.h.

Reviewers: pete, chandlerc

Subscribers: llvm-commits, jfb

Differential Revision: https://reviews.llvm.org/D31940

llvm-svn: 300014
2017-04-12 00:38:00 +00:00
Reid Kleckner eb9dd5b87f Reland "[IR] Make AttributeSetNode public, avoid temporary AttributeList copies"
This re-lands r299875.

I introduced a bug in Clang code responsible for replacing K&R, no
prototype declarations with a real function definition with a prototype.
The bug was here:

       // Collect any return attributes from the call.
  -    if (oldAttrs.hasAttributes(llvm::AttributeList::ReturnIndex))
  -      newAttrs.push_back(llvm::AttributeList::get(newFn->getContext(),
  -                                                  oldAttrs.getRetAttributes()));
  +    newAttrs.push_back(oldAttrs.getRetAttributes());

Previously getRetAttributes() carried AttributeList::ReturnIndex in its
AttributeList. Now that we return the AttributeSetNode* directly, it no
longer carries that index, and we call this overload with a single node:
  AttributeList::get(LLVMContext&, ArrayRef<AttributeSetNode*>)

That aborted with an assertion on x86_32 targets. I added an explicit
triple to the test and added CHECKs to help find issues like this in the
future sooner.

llvm-svn: 299899
2017-04-10 23:31:05 +00:00
Reid Kleckner 211b1f324f Revert "[IR] Make AttributeSetNode public, avoid temporary AttributeList copies"
This reverts r299875. A Linux bot came back with a test failure:
http://bb.pgr.jp/builders/test-clang-i686-linux-RA/builds/741/steps/test_clang/logs/Clang%20%3A%3A%20CodeGen__2006-05-19-SingleEltReturn.c

llvm-svn: 299878
2017-04-10 20:34:19 +00:00
Reid Kleckner 324c99dee5 [IR] Make AttributeSetNode public, avoid temporary AttributeList copies
Summary:
AttributeList::get(Fn|Ret|Param)Attributes no longer creates a temporary
AttributeList just to hide the AttributeSetNode type.

I've also added a factory method to create AttributeLists from a
parallel array of AttributeSetNodes. I think this simplifies
construction of AttributeLists when rewriting function prototypes.
Previously we would test if a particular index had attributes, and
conditionally add a temporary attribute list to a vector. Now the
attribute set vector is parallel to the argument vector already that
these passes already construct.

My long term vision is to wrap AttributeSetNode* inside an AttributeSet
type that holds the enum attributes, but that will come in a follow up
change.

I haven't done any performance measurements for this change because
profiling hasn't shown that any of the affected code is hot.

Reviewers: pete, chandlerc, sanjoy, hfinkel

Reviewed By: pete

Subscribers: jfb, llvm-commits

Differential Revision: https://reviews.llvm.org/D31198

llvm-svn: 299875
2017-04-10 20:18:10 +00:00
Reid Kleckner b518054b87 Rename AttributeSet to AttributeList
Summary:
This class is a list of AttributeSetNodes corresponding the function
prototype of a call or function declaration. This class used to be
called ParamAttrListPtr, then AttrListPtr, then AttributeSet. It is
typically accessed by parameter and return value index, so
"AttributeList" seems like a more intuitive name.

Rename AttributeSetImpl to AttributeListImpl to follow suit.

It's useful to rename this class so that we can rename AttributeSetNode
to AttributeSet later. AttributeSet is the set of attributes that apply
to a single function, argument, or return value.

Reviewers: sanjoy, javed.absar, chandlerc, pete

Reviewed By: pete

Subscribers: pete, jholewinski, arsenm, dschuff, mehdi_amini, jfb, nhaehnle, sbc100, void, llvm-commits

Differential Revision: https://reviews.llvm.org/D31102

llvm-svn: 298393
2017-03-21 16:57:19 +00:00
Sanjoy Das 8b859c26ec [JumpThreading] Re-enable JumpThreading for guards
Summary:
JumpThreading for guards feature has been reverted at https://reviews.llvm.org/rL295200
due to the following problem: the feature used the following algorithm for detection of
diamond patters:

1. Find a block with 2 predecessors;
2. Check that these blocks have a common single parent;
3. Check that the parent's terminator is a branch instruction.

The problem is that these checks are insufficient. They may pass for a non-diamond
construction in case if those two predecessors are actually the same block. This may
happen if parent's terminator is a br (either conditional or unconditional) to a block
that ends with "switch" instruction with exactly two branches going to one block.

This patch re-enables the JumpThreading for guards and fixes this issue by adding the
check that those found predecessors are actually different blocks. This guarantees that
parent's terminator is a conditional branch with exactly 2 different successors, which
is now ensured by assertions. It also adds two more tests for this situation (with parent's
terminator being a conditional and an unconditional branch).

Patch by Max Kazantsev!

Reviewers: anna, sanjoy, reames

Reviewed By: sanjoy

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D30036

llvm-svn: 295410
2017-02-17 04:21:14 +00:00
Anna Thomas 94c8d4976c Revert "[JumpThreading] Thread through guards"
This reverts commit r294617.

We fail on an assert while trying to get a condition from an
unconditional branch.

llvm-svn: 295200
2017-02-15 17:08:29 +00:00
Sanjoy Das 74bda4d591 [JumpThreading] Thread through guards
Summary:
This patch allows JumpThreading also thread through guards.
Virtually, guard(cond) is equivalent to the following construction:

  if (cond) { do something } else {deoptimize}

Yet it is not explicitly converted into IFs before lowering.
This patch enables early threading through guards in simple cases.
Currently it covers the following situation:

  if (cond1) {
    // code A
  } else {
    // code B
  }
  // code C
  guard(cond2)
  // code D

If there is implication cond1 => cond2 or !cond1 => cond2, we can transform
this construction into the following:

  if (cond1) {
    // code A
    // code C
  } else {
    // code B
    // code C
    guard(cond2)
  }
  // code D

Thus, removing the guard from one of execution branches.

Patch by Max Kazantsev!

Reviewers: reames, apilipenko, igor-laevsky, anna, sanjoy

Reviewed By: sanjoy

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D29620

llvm-svn: 294617
2017-02-09 19:40:22 +00:00
David Majnemer 5554edabef [CloneFunction] Don't remove unrelated nodes from the CGSSC
CGSCC use a WeakVH to track call sites.  RAUW a call within a function
can result in that WeakVH getting confused about whether or not the call
site is still around.

llvm-svn: 279268
2016-08-19 16:37:40 +00:00
David Majnemer 4eefd6bca4 Forgot the dyn_cast_or_null intended for r277691.
llvm-svn: 277693
2016-08-04 04:47:18 +00:00
David Majnemer 909793fa63 Reinstate "[CloneFunction] Don't remove side effecting calls"
This reinstates r277611 + r277614 and reverts r277642.  A cast_or_null
should have been a dyn_cast_or_null.

llvm-svn: 277691
2016-08-04 04:24:02 +00:00
Reid Kleckner a6be60871f Revert "[CloneFunction] Don't remove side effecting calls"
This reverts commit r277611 and the followup r277614.

Bootstrap builds and chromium builds are crashing during inlining after
this change.

llvm-svn: 277642
2016-08-03 20:01:01 +00:00
David Majnemer fa8ef91748 [CloneFunction] Don't crash if the value map doesn't hold something
It is possible for the value map to not have an entry for some value
that has already been removed.

I don't have a testcase, this is fall-out from a buildbot.

llvm-svn: 277614
2016-08-03 17:37:10 +00:00
David Majnemer fad0490869 [CloneFunction] Don't remove side effecting calls
We were able to figure out that the result of a call is some constant.
While propagating that fact, we added the constant to the value map.
This is problematic because it results in us losing the call site when
processing the value map.

This fixes PR28802.

llvm-svn: 277611
2016-08-03 17:12:47 +00:00
Benjamin Kramer 135f735af1 Apply clang-tidy's modernize-loop-convert to most of lib/Transforms.
Only minor manual fixes. No functionality change intended.

llvm-svn: 273808
2016-06-26 12:28:59 +00:00
David Majnemer b8da3a2bb2 Reinstate r273711
r273711 was reverted by r273743.  The inliner needs to know about any
call sites in the inlined function.  These were obscured if we replaced
a call to undef with an undef but kept the call around.

This fixes PR28298.

llvm-svn: 273753
2016-06-25 00:04:10 +00:00
Nico Weber ae2ef4ccd4 Revert r273711, it caused PR28298.
llvm-svn: 273743
2016-06-24 22:52:39 +00:00
David Majnemer 3b3e954ea2 SimplifyInstruction does not imply DCE
We cannot remove an instruction with no uses just because
SimplifyInstruction succeeds.  It may have side effects.

llvm-svn: 273711
2016-06-24 19:34:46 +00:00
Vikram TV c702b8b3d7 Delay dominator updation while cloning loop.
Summary:
Dominator updation fails for a loop inserted with a new basicblock.

A block required by DT to set the IDom might not have been cloned yet. This is because there is no predefined ordering of loop blocks (except for the header block which should be the first block in the list).

The patch first creates DT nodes for the cloned blocks and then separately updates the DT in a follow-on loop.

Reviewers: anemet, dberlin

Subscribers: dberlin, llvm-commits

Differential Revision: http://reviews.llvm.org/D20899

llvm-svn: 272479
2016-06-11 16:41:10 +00:00
Peter Collingbourne 382d81cacf IR: Allow multiple global metadata attachments with the same type.
This will be necessary to allow the global merge pass to attach
multiple debug info metadata nodes to global variables once we reverse
the edge from DIGlobalVariable to GlobalVariable.

Differential Revision: http://reviews.llvm.org/D20414

llvm-svn: 271358
2016-06-01 01:17:57 +00:00