Summary: This patch adds a PDT constructor from Function and lets codes previously using a local class to do this use PostDominatorTree class directly.
Reviewers: davide, kuhar, grosser, dberlin
Reviewed By: kuhar
Author: NutshellySima
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D46709
llvm-svn: 333102
r332057 introduced distance() for ranges. Based on post-commit feedback,
this renames distance() to size(). The new size() is also only enabled
when the operation is O(1).
Differential Revision: https://reviews.llvm.org/D46976
llvm-svn: 332551
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
Summary:
Currently the order of blocks returned by `IDF::calculate` can be
non-deterministic. This was discovered in several attempts to enable
SSAUpdaterBulk for JumpThreading (which led to miscompare in bootstrap between
stage 3 and stage4). Originally, the blocks were put into a priority queue with
a depth level as their key, and this patch adds a DFSIn number as a second key
to specify a deterministic order across blocks from one level.
The solution was suggested by Daniel Berlin.
Reviewers: dberlin, davide
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D46646
llvm-svn: 332167
Summary: Fix two typos which result in verifying wrong data structures (DT) instead of PDT in DominatorTreeBatchUpdatesTest.
Reviewers: davide, kuhar, grosser, dberlin
Reviewed By: davide, kuhar, dberlin
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D46696
llvm-svn: 332086
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
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
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
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
LLVM_ON_WIN32 is set exactly with MSVC and MinGW (but not Cygwin) in
HandleLLVMOptions.cmake, which is where _WIN32 defined too. Just use the
default macro instead of a reinvented one.
See thread "Replacing LLVM_ON_WIN32 with just _WIN32" on llvm-dev and cfe-dev.
No intended behavior change.
This moves over all uses of the macro, but doesn't remove the definition
of it in (llvm-)config.h yet.
llvm-svn: 331127
Summary:
Currently, we
1. match `LHS` matcher to the `first` operand of binary operator,
2. and then match `RHS` matcher to the `second` operand of binary operator.
If that does not match, we swap the `LHS` and `RHS` matchers:
1. match `RHS` matcher to the `first` operand of binary operator,
2. and then match `LHS` matcher to the `second` operand of binary operator.
This works ok.
But it complicates writing of commutative matchers, where one would like to match
(`m_Value()`) the value on one side, and use (`m_Specific()`) it on the other side.
This is additionally complicated by the fact that `m_Specific()` stores the `Value *`,
not `Value **`, so it won't work at all out of the box.
The last problem is trivially solved by adding a new `m_c_Specific()` that stores the
`Value **`, not `Value *`. I'm choosing to add a new matcher, not change the existing
one because i guess all the current users are ok with existing behavior,
and this additional pointer indirection may have performance drawbacks.
Also, i'm storing pointer, not reference, because for some mysterious-to-me reason
it did not work with the reference.
The first one appears trivial, too.
Currently, we
1. match `LHS` matcher to the `first` operand of binary operator,
2. and then match `RHS` matcher to the `second` operand of binary operator.
If that does not match, we swap the ~~`LHS` and `RHS` matchers~~ **operands**:
1. match ~~`RHS`~~ **`LHS`** matcher to the ~~`first`~~ **`second`** operand of binary operator,
2. and then match ~~`LHS`~~ **`RHS`** matcher to the ~~`second`~ **`first`** operand of binary operator.
Surprisingly, `$ ninja check-llvm` still passes with this.
But i expect the bots will disagree..
The motivational unittest is included.
I'd like to use this in D45664.
Reviewers: spatel, craig.topper, arsenm, RKSimon
Reviewed By: craig.topper
Subscribers: xbolva00, wdng, llvm-commits
Differential Revision: https://reviews.llvm.org/D45828
llvm-svn: 331085
This makes it possible to reverse a filtered range. For example, here's
a way to visit memory accesses in a BasicBlock in reverse order:
auto MemInsts = reverse(make_filter_range(BB, [](Instruction &I) {
return isa<StoreInst>(&I) || isa<LoadInst>(&I);
}));
for (auto &MI : MemInsts)
...
To implement this functionality, I factored out forward iteration
functionality into filter_iterator_base, and added a specialization of
filter_iterator_impl which supports bidirectional iteration. Thanks to
Tim Shen, Zachary Turner, and others for suggesting this design and
providing feedback! This version of the patch supersedes the original
(https://reviews.llvm.org/D45792).
This was motivated by a problem we encountered in D45657: we'd like to
visit the non-debug-info instructions in a BasicBlock in reverse order.
Testing: check-llvm, check-clang
Differential Revision: https://reviews.llvm.org/D45853
llvm-svn: 330875
The code uses the index of the last element in the sorted array to determine the maximum size needed for the vector. But if the last index is a FunctionIndex(~0), attrIdxToArrayIdx will return 0 and the vector will have size 1. If there are any indices before FunctionIndex, those values would return a value larger than 0 from attrIdxToArrayIdx. So in this case we need to look in front of the FunctionIndex to get the true size needed.
Differential Revision: https://reviews.llvm.org/D45632
llvm-svn: 330136
This patch introduces a way to set custom OptPassGate instances to LLVMContext.
A new instance field OptBisector and a new method setOptBisect() are added
to the LLVMContext classes. These changes allow to set a custom OptBisect class
that can make its own decisions on skipping optional passes.
Another important feature of this change is ability to set different instances
of OptPassGate to different LLVMContexts. So the different contexts can be used
independently in several compiling threads of one process.
One unit test is added.
Patch by Yevgeny Rouban.
Reviewers: andrew.w.kaylor, fedor.sergeev, vsk, dberlin, Eugene.Zelenko, reames, skatkov
Reviewed By: andrew.w.kaylor, fedor.sergeev
Differential Revision: https://reviews.llvm.org/D44464
llvm-svn: 329267
Summary:
There aren't any matchers for the three vector operations: insertelement, extractelement, and
shufflevector. This patch adds them as well as corresponding unit tests.
llvm-svn: 328709
Value::printAsOperand has been scanning the entire module just to
print a single value as an operand, regardless being asked to print a
type or not at all, and regardless really needing to scan the module
to print a type.
It made some of the users of the method exceptionally slow on large
IR-modules (or large MIR-files with large IR-modules embedded).
This patch defers scanning a module looking for struct types, mostly
numbered struct types, as much as possible, speeding up those users
w/o changing any APIs at all.
See speedup examples below:
Release Build:
# 83 seconds -> 5.5 seconds
time ./bin/llc -start-before=irtranslator -stop-after=irtranslator \
-global-isel -global-isel-abort=2 -simplify-mir sqlite3.O0.ll -o \
sqlite3.O0.ll.regbankselected.mir
# 133 seconds -> 6.2 seconds
time ./bin/opt sqlite3.O0.ll -dot-cfg -disable-output
Release + Asserts Build:
# 95 seconds -> 5.5 seconds
time ./bin/llc -start-before=irtranslator -stop-after=irtranslator \
-global-isel -global-isel-abort=2 -simplify-mir sqlite3.O0.ll -o \
sqlite3.O0.ll.regbankselected.mir
# 146 seconds -> 6.2 seconds
time ./bin/opt sqlite3.O0.ll -dot-cfg -disable-output
# 1096 seconds -> 553 seconds
time ./bin/llc -debug-only=isel -fast-isel=false -stop-after=isel \
sqlite3.O0.ll -o /dev/null 2> err
where sqlite3.O0.ll is non-optimized IR produced from
sqlite-amalgamation (http://sqlite.org/download.html), which is entire
SQLite3 implementation in a single C-file.
Benchmarked on 4-cores / 8 threads PCI-E SSD iMac running macOS
Reviewers: dexonsmith, bkramer, void, chandlerc, aditya_nandakumar, dsanders, qcolombet,
Reviewed By: bogner
Subscribers: thegameg, llvm-commits
Differential Revision: https://reviews.llvm.org/D44132
llvm-svn: 328246
Now the Windows mangling modes ('w' and 'x') do not do any mangling for
symbols starting with '?'. This means that clang can stop adding the
hideous '\01' leading escape. This means LLVM debug logs are less likely
to contain ASCII escape characters and it will be easier to copy and
paste MS symbol names from IR.
Finally.
For non-Windows platforms, names starting with '?' still get IR
mangling, so once clang stops escaping MS C++ names, we will get extra
'_' prefixing on MachO. That's fine, since it is currently impossible to
construct a triple that uses the MS C++ ABI in clang and emits macho
object files.
Differential Revision: https://reviews.llvm.org/D7775
llvm-svn: 327734
Removes verifyDomTree, using assert(verify()) everywhere instead, and
changes verify a little to always run IsSameAsFreshTree first in order
to print good output when we find errors. Also adds verifyAnalysis for
PostDomTrees, which will allow checking of PostDomTrees it the same way
we check DomTrees and MachineDomTrees.
Differential Revision: https://reviews.llvm.org/D41298
llvm-svn: 326315
In DWARF v5 the Line Number Program Header is extensible, allowing values with
new content types. In this extension a content type is added,
DW_LNCT_LLVM_source, which contains the embedded source code of the file.
Add new optional attribute for !DIFile IR metadata called source which contains
source text. Use this to output the source to the DWARF line table of code
objects. Analogously extend METADATA_FILE in Bitcode and .file directive in ASM
to support optional source.
Teach llvm-dwarfdump and llvm-objdump about the new values. Update the output
format of llvm-dwarfdump to make room for the new attribute on file_names
entries, and support embedded sources for the -source option in llvm-objdump.
Differential Revision: https://reviews.llvm.org/D42765
llvm-svn: 325970
The bug was introduced here:
https://reviews.llvm.org/rL296409
...but the patch doesn't use maxnum and nothing else in
trunk has tried since then, so the bug went unnoticed.
llvm-svn: 325607
Commit https://reviews.llvm.org/rL324489 added
EXPECT_EQ(false, N->isUnsigned());
which older GCC versions dislike for some reason. Anyway, it looks like the
proper GTest way is to use EXPECT_FALSE, etc.
Differential Revision: https://reviews.llvm.org/D43233
llvm-svn: 325121
Rather than encode the absence of a checksum with a Kind variant, instead put
both the kind and value in a struct and wrap it in an Optional.
Differential Revision: http://reviews.llvm.org/D43043
llvm-svn: 324928
This patch is the LLVM part of fixing the issues, described in
https://bugs.llvm.org/show_bug.cgi?id=36168
* The representation of enumerator values in the debug info metadata now
contains a boolean flag isUnsigned, which determines how the bits of
the value are interpreted.
* The DW_TAG_enumeration type DIE now always (for DWARF version >= 3)
includes a DW_AT_type attribute, which refers to the underlying
integer type, as suggested in DWARFv4 (5.7 Enumeration Type Entries).
* The debug info metadata for enumeration type contains (in flags)
indication whether this is a C++11 "fixed enum".
* For C++11 enumeration with a fixed underlying type, the DIE also
includes the DW_AT_enum_class attribute (for DWARF version >= 4).
* Encoding of enumerator constants uses DW_FORM_sdata for signed values
and DW_FORM_udata for unsigned values, as suggested by DWARFv4 (7.5.4
Attribute Encodings).
The changes should be backwards compatible:
* the isUnsigned attribute is optional and defaults to false.
* if the underlying type for the enumeration is not available, the
enumerator values are considered signed.
* the FixedEnum flag defaults to clear.
* the bitcode format for DIEnumerator stores the unsigned flag bit #1 of
the first record element, so the format does not change and the zero
previously stored there is consistent with the false default for
IsUnsigned.
Differential Revision: https://reviews.llvm.org/D42734
llvm-svn: 324489
n Rust, an enum that carries data in the variants is, essentially, a
discriminated union. Furthermore, the Rust compiler will perform
space optimizations on such enums in some situations. Previously,
DWARF for these constructs was emitted using a hack (a magic field
name); but this approach stopped working when more space optimizations
were added in https://github.com/rust-lang/rust/pull/45225.
This patch changes LLVM to allow discriminated unions to be
represented in DWARF. It adds createDiscriminatedUnionType and
createDiscriminatedMemberType to DIBuilder and then arranges for this
to be emitted using DWARF's DW_TAG_variant_part and DW_TAG_variant.
Note that DWARF requires that a discriminated union be represented as
a structure with a variant part. However, as Rust only needs to emit
pure discriminated unions, this is what I chose to expose on
DIBuilder.
Patch by Tom Tromey!
Differential Revision: https://reviews.llvm.org/D42082
llvm-svn: 324426
Summary:
This patch extends the DISubrange 'count' field to take either a
(signed) constant integer value or a reference to a DILocalVariable
or DIGlobalVariable.
This is patch [1/3] in a series to extend LLVM's DISubrange Metadata
node to support debugging of C99 variable length arrays and vectors with
runtime length like the Scalable Vector Extension for AArch64. It is
also a first step towards representing more complex cases like arrays
in Fortran.
Reviewers: echristo, pcc, aprantl, dexonsmith, clayborg, kristof.beyls, dblaikie
Reviewed By: aprantl
Subscribers: rnk, probinson, fhahn, aemerson, rengolin, JDevlieghere, llvm-commits
Differential Revision: https://reviews.llvm.org/D41695
llvm-svn: 323313
Summary:
It's generally not safe to perform multiple DomTree updates without using the incremental API.
Although it is supposed to work in this particular case, the testcase is misleading/confusing, and it's better to remove it.
Reviewers: dberlin, brzycki, davide, grosser
Reviewed By: davide
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D42333
llvm-svn: 323058
These fix some odd cfg cases where batch-updating the post
dom tree fails. Usually around infinite loops and roots
ending up being different.
Differential Revision: https://reviews.llvm.org/D42247
llvm-svn: 323034
Summary:
This patch attempts to fix the DomTree incremental insertion bug found here [[ https://bugs.llvm.org/show_bug.cgi?id=35969 | PR35969 ]] .
When performing an insertion into a piece of unreachable CFG, we may find the same not at different levels. When this happens, the node can turn out to be affected when we find it starting from a node with a lower level in the tree. The level at which we start visitation affects if we consider a node affected or not.
This patch tracks the lowest level at which each node was visited during insertion and allows it to be visited multiple times, if it can cause it to be considered affected.
Reviewers: brzycki, davide, dberlin, grosser
Reviewed By: brzycki
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D42231
llvm-svn: 322993
Summary:
The class wraps a uint64_t and an enum to represent the type of profile
count (real and synthetic) with some helper methods.
Reviewers: davidxl
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D41883
llvm-svn: 322771
Summary:
Discovered while working on a patch to move alignment in
@llvm.memcpy/move/set from an arg into parameter attributes.
The current implementations of AttributeSet::removeAttribute() and
AttributeList::removeAttribute crash when attempting to remove the
alignment attribute. Currently, these implementations add the
to-be-removed attributes to an AttrBuilder and then remove
the builder from the list/set. Alignment is special in that it
must be added to a builder with an integer value for the alignment;
attempts to add alignment to a builder without a value is an error.
This change fixes the removeAttribute implementations for AttributeSet and
AttributeList to make them able to remove the alignment, and other similar,
attributes.
Reviewers: rnk, chandlerc, pete, javed.absar, reames
Reviewed By: rnk
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D41951
llvm-svn: 322735
Summary:
See D37528 for a previous (non-deferred) version of this
patch and its description.
Preserves dominance in a deferred manner using a new class
DeferredDominance. This reduces the performance impact of
updating the DominatorTree at every edge insertion and
deletion. A user may call DDT->flush() within JumpThreading
for an up-to-date DT. This patch currently has one flush()
at the end of runImpl() to ensure DT is preserved across
the pass.
LVI is also preserved to help subsequent passes such as
CorrelatedValuePropagation. LVI is simpler to maintain and
is done immediately (not deferred). The code to perform the
preversation was minimally altered and simply marked as
preserved for the PassManager to be informed.
This extends the analysis available to JumpThreading for
future enhancements such as threading across loop headers.
Reviewers: dberlin, kuhar, sebpop
Reviewed By: kuhar, sebpop
Subscribers: mgorny, dmgreen, kuba, rnk, rsmith, hiraditya, llvm-commits
Differential Revision: https://reviews.llvm.org/D40146
llvm-svn: 322401
Extend the ConstantRange implementation to compute the range of possible values resulting from an arithmetic right shift operation.
There will be a follow up patch to leverage this constant range infrastructure in LazyValueInfo.
Patch by Surya Kumari Jangala!
Differential Revision: https://reviews.llvm.org/D40881
llvm-svn: 320976
Previously ConstantRange::makeGuaranteedNoWrapRegion only handled addition. This adds support for subtraction.
Differential Revision: https://reviews.llvm.org/D40036
llvm-svn: 319806
In Rust, a trait can be implemented for any type, and if a trait
object pointer is used for the type, then a virtual table will be
emitted for that trait/type combination.
We would like debuggers to be able to inspect trait objects, which
requires finding the concrete type associated with a given vtable.
This patch changes LLVM so that any type can be passed to
replaceVTableHolder. This allows the Rust compiler to emit the needed
debug info -- associating a vtable with the concrete type for which it
was emitted.
This is a DWARF extension: DWARF only specifies the meaning of
DW_AT_containing_type in one specific situation. This style of DWARF
extension is routine, though, and LLVM already has one such case for
DW_AT_containing_type.
Patch by Tom Tromey!
Differential Revision: https://reviews.llvm.org/D39503
llvm-svn: 317730
As discussed on llvm-dev:
http://lists.llvm.org/pipermail/llvm-dev/2016-November/107104.html
and again more recently:
http://lists.llvm.org/pipermail/llvm-dev/2017-October/118118.html
...this is a step in cleaning up our fast-math-flags implementation in IR to better match
the capabilities of both clang's user-visible flags and the backend's flags for SDNode.
As proposed in the above threads, we're replacing the 'UnsafeAlgebra' bit (which had the
'umbrella' meaning that all flags are set) with a new bit that only applies to algebraic
reassociation - 'AllowReassoc'.
We're also adding a bit to allow approximations for library functions called 'ApproxFunc'
(this was initially proposed as 'libm' or similar).
...and we're out of bits. 7 bits ought to be enough for anyone, right? :) FWIW, I did
look at getting this out of SubclassOptionalData via SubclassData (spacious 16-bits),
but that's apparently already used for other purposes. Also, I don't think we can just
add a field to FPMathOperator because Operator is not intended to be instantiated.
We'll defer movement of FMF to another day.
We keep the 'fast' keyword. I thought about removing that, but seeing IR like this:
%f.fast = fadd reassoc nnan ninf nsz arcp contract afn float %op1, %op2
...made me think we want to keep the shortcut synonym.
Finally, this change is binary incompatible with existing IR as seen in the
compatibility tests. This statement:
"Newer releases can ignore features from older releases, but they cannot miscompile
them. For example, if nsw is ever replaced with something else, dropping it would be
a valid way to upgrade the IR."
( http://llvm.org/docs/DeveloperPolicy.html#ir-backwards-compatibility )
...provides the flexibility we want to make this change without requiring a new IR
version. Ie, we're not loosening the FP strictness of existing IR. At worst, we will
fail to optimize some previously 'fast' code because it's no longer recognized as
'fast'. This should get fixed as we audit/squash all of the uses of 'isFast()'.
Note: an inter-dependent clang commit to use the new API name should closely follow
commit.
Differential Revision: https://reviews.llvm.org/D39304
llvm-svn: 317488
This came out of a recent discussion on llvm-dev
(https://reviews.llvm.org/D38042). Currently the Verifier will strip
the debug info metadata from a module if it finds the dbeug info to be
malformed. This feature is very valuable since it allows us to improve
the Verifier by making it stricter without breaking bcompatibility,
but arguable the Verifier pass should not be modifying the IR. This
patch moves the stripping of broken debug info into AutoUpgrade
(UpgradeDebugInfo to be precise), which is a much better location for
this since the stripping of malformed (i.e., produced by older, buggy
versions of Clang) is a (harsh) form of AutoUpgrade.
This change is mostly NFC in nature, the one big difference is the
behavior when LLVM module passes are introducing malformed debug
info. Prior to this patch, a NoAsserts build would have printed a
warning and stripped the debug info, after this patch the Verifier
will report a fatal error. I believe this behavior is actually more
desirable anyway.
Differential Revision: https://reviews.llvm.org/D38184
llvm-svn: 314699
This reverts commit 6389e7aa724ea7671d096f4770f016c3d86b0d54.
There is a bug in this implementation where the string value of the
checksum is outputted, instead of the actual hex bytes. Therefore the
checksum is incorrect, and this prevent pdbs from being loaded by visual
studio. Revert this until the checksum is emitted correctly.
llvm-svn: 313431
Summary:
The checksums had already been placed in the IR, this patch allows
MCCodeView to actually write it out to an MCStreamer.
Subscribers: llvm-commits, hiraditya
Differential Revision: https://reviews.llvm.org/D37157
llvm-svn: 313374
Now that we print DIExpressions inline everywhere, we don't need to
print them once as an operand and again as a value. This is only really
visible when calling dump() or print() directly on a DIExpression during
debugging.
llvm-svn: 312168
Summary:
This patch introduces a way of informing the (Post)DominatorTree about multiple CFG updates that happened since the last tree update. This makes performing tree updates much easier, as it internally takes care of applying the updates in lockstep with the (virtual) updates to the CFG, which is done by reverse-applying future CFG updates.
The batch updater is able to remove redundant updates that cancel each other out. In the future, it should be also possible to reorder updates to reduce the amount of work needed to perform the updates.
Reviewers: dberlin, sanjoy, grosser, davide, brzycki
Reviewed By: brzycki
Subscribers: mgorny, llvm-commits
Differential Revision: https://reviews.llvm.org/D36167
llvm-svn: 311015
Summary:
This patch teaches PostDominatorTree about infinite loops. It is built on top of D29705 by @dberlin which includes a very detailed motivation for this change.
What's new is that the patch also teaches the incremental updater how to deal with reverse-unreachable regions and how to properly maintain and verify tree roots. Before that, the incremental algorithm sometimes ended up preserving reverse-unreachable regions after updates that wouldn't appear in the tree if it was constructed from scratch on the same CFG.
This patch makes the following assumptions:
- A sequence of updates should produce the same tree as a recalculating it.
- Any sequence of the same updates should lead to the same tree.
- Siblings and roots are unordered.
The last two properties are essential to efficiently perform batch updates in the future.
When it comes to the first one, we can decide later that the consistency between freshly built tree and an updated one doesn't matter match, as there are many correct ways to pick roots in infinite loops, and to relax this assumption. That should enable us to recalculate postdominators less frequently.
This patch is pretty conservative when it comes to incremental updates on reverse-unreachable regions and ends up recalculating the whole tree in many cases. It should be possible to improve the performance in many cases, if we decide that it's important enough.
That being said, my experiments showed that reverse-unreachable are very rare in the IR emitted by clang when bootstrapping clang. Here are the statistics I collected by analyzing IR between passes and after each removePredecessor call:
```
# functions: 52283
# samples: 337609
# reverse unreachable BBs: 216022
# BBs: 247840796
Percent reverse-unreachable: 0.08716159869015269 %
Max(PercRevUnreachable) in a function: 87.58620689655172 %
# > 25 % samples: 471 ( 0.1395104988314885 % samples )
... in 145 ( 0.27733680163724345 % functions )
```
Most of the reverse-unreachable regions come from invalid IR where it wouldn't be possible to construct a PostDomTree anyway.
I would like to commit this patch in the next week in order to be able to complete the work that depends on it before the end of my internship, so please don't wait long to voice your concerns :).
Reviewers: dberlin, sanjoy, grosser, brzycki, davide, chandlerc, hfinkel
Reviewed By: dberlin
Subscribers: nhaehnle, javed.absar, kparzysz, uabelho, jlebar, hiraditya, llvm-commits, dberlin, david2050
Differential Revision: https://reviews.llvm.org/D35851
llvm-svn: 310940
They hang for me locally. I suspect that there is a use-after-free when
attempting to destroy an LLVMContext after asserting from the middle of
metadata tracking. It doesn't seem worth debugging it further.
llvm-svn: 310660
Remove the second part of the TODO comment that highlighted an issue with
possibly connecting all nodes to the exit of the CFG. This caused concerns
with Jakub Kuderski regarding its feasability, hence we remove it. Such
points are better discussed outside of CFG. If connecting all nodes makes
sense and what the impact is is currently part of an active review discussion.
llvm-svn: 309919
Summary:
This patch makes LoopDeletion use the incremental DominatorTree API.
We modify LoopDeletion to perform the deletion in 5 steps:
1. Create a new dummy edge from the preheader to the exit, by adding a conditional branch.
2. Inform the DomTree about the new edge.
3. Remove the conditional branch and replace it with an unconditional edge to the exit. This removes the edge to the loop header, making it unreachable.
4. Inform the DomTree about the deleted edge.
5. Remove the unreachable block from the function.
Creating the dummy conditional branch is necessary to perform incremental DomTree update.
We should consider using the batch updater when it's ready.
Reviewers: dberlin, davide, grosser, sanjoy
Reviewed By: dberlin, grosser
Subscribers: mzolotukhin, llvm-commits
Differential Revision: https://reviews.llvm.org/D35391
llvm-svn: 309850
Summary:
As we are in the process of changing the behavior of how the post-dominator tree
is computed, make sure we have some more test coverage in this area.
Current inconsistencies:
- Newly unreachable nodes are not added as new roots, in case the PDT is updated
but not rebuilt.
- Newly unreachable loops are not added to the CFG at all (neither when
building from scratch nor when updating the CFG). This is inconsistent with
the fact that unreachables are added to the PDT, but unreachable loops not.
On the other side, PDT relationships are not loosened at the moment in
cases where new unreachable loops are built.
This commit is providing additional test coverage for
https://reviews.llvm.org/D35851
Reviewers: dberlin, kuhar
Reviewed By: kuhar
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D36107
llvm-svn: 309684
DIImportedEntity has a line number, but not a file field. To determine
the decl_line/decl_file we combine the line number from the
DIImportedEntity with the file from the DIImportedEntity's scope. This
does not work correctly when the parent scope is a DINamespace or a
DIModule, both of which do not have a source file.
This patch adds a file field to DIImportedEntity to unambiguously
identify the source location of the using/import declaration. Most
testcase updates are mechanical, the interesting one is the removal of
the FIXME in test/DebugInfo/Generic/namespace.ll.
This fixes PR33822. See https://bugs.llvm.org/show_bug.cgi?id=33822
for more context.
<rdar://problem/33357889>
https://bugs.llvm.org/show_bug.cgi?id=33822
Differential Revision: https://reviews.llvm.org/D35583
llvm-svn: 308398
This fixes a minor bug in insertion to a reachable node that caused
DominatorTree.InsertDeleteExhaustive flakiness. The patch also adds
a new testcase for this exact failure.
llvm-svn: 308074
The DominatorTree.InsertDeleteExhaustive uses a RNG with a
constant seed to generate different sequences of updates. The test
fails on some buildbots and this patch disables it for now.
llvm-svn: 308070
Summary:
This patch implements incremental edge deletions.
It also makes DominatorTreeBase store a pointer to the parent function. The parent function is needed to perform full rebuilts during some deletions, but it is also used to verify that inserted and deleted edges come from the same function.
Reviewers: dberlin, davide, grosser, sanjoy, brzycki
Reviewed By: dberlin
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D35342
llvm-svn: 308062
Summary:
This patch introduces incremental edge insertions based on the Depth Based Search algorithm.
Insertions should work for both dominators and postdominators.
Reviewers: dberlin, grosser, davide, sanjoy, brzycki
Reviewed By: dberlin
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D35341
llvm-svn: 308054
Summary:
DominatorTreeBase used to have IsPostDominators (bool) member to indicate if the tree is a dominator or a postdominator tree. This made it possible to switch between the two 'modes' at runtime, but it isn't used in practice anywhere.
This patch makes IsPostDominator a template argument. This way, it is easier to switch between different algorithms at compile-time based on this argument and design external utilities around it. It also makes it impossible to incidentally assign a postdominator tree to a dominator tree (and vice versa), and to further simplify template code in GenericDominatorTreeConstruction.
Reviewers: dberlin, sanjoy, davide, grosser
Reviewed By: dberlin
Subscribers: mzolotukhin, llvm-commits
Differential Revision: https://reviews.llvm.org/D35315
llvm-svn: 308040
Summary:
This patch introduces a new testing utility for building and modifying CFG -- CFGBuilder. The primary use case for the utility is testing the upcoming incremental dominator tree update API.
The current design provides a simple mechanism of constructing arbitrary graphs and then applying series of updates to them. CFGBuilder takes care of creating empty functions, connecting and disconnecting basic blocks. Under the hood it uses SwitchInst and UnreachableInst.
It will be also possible to create a thin wrapper over CFGBuilder for parsing string input and to hook it up to other textual tools (e.g. opt used with FileCheck).
Reviewers: dberlin, sanjoy, grosser, dblaikie
Reviewed By: dblaikie
Subscribers: davide, mgorny, llvm-commits
Differential Revision: https://reviews.llvm.org/D34798
llvm-svn: 307960
Summary:
This patch adds a callback registration API to the PassBuilder,
enabling registering out-of-tree passes with it.
Through the Callback API, callers may register callbacks with the
various stages at which passes are added into pass managers, including
parsing of a pass pipeline as well as at extension points within the
default -O pipelines.
Registering utilities like `require<>` and `invalidate<>` needs to be
handled manually by the caller, but a helper is provided.
Additionally, adding passes at pipeline extension points is exposed
through the opt tool. This patch adds a `-passes-ep-X` commandline
option for every extension point X, which opt parses into pipelines
inserted into that extension point.
Reviewers: chandlerc
Reviewed By: chandlerc
Subscribers: lksbhm, grosser, davide, mehdi_amini, llvm-commits, mgorny
Differential Revision: https://reviews.llvm.org/D33464
llvm-svn: 307532
This reverts commit r306907 and reapplies the patches in the title.
The patches used to make one of the
CodeGen/ARM/2011-02-07-AntidepClobber.ll test to fail because of a
missing null check.
llvm-svn: 306919
This reverts commit r306894.
Revert "[Dominators] Add NearestCommonDominator verification"
This reverts commit r306893.
Revert "[Dominators] Keep tree level in DomTreeNode and use it to find NCD and answer dominance queries"
This reverts commit r306892.
llvm-svn: 306907
Summary:
This patch makes DomTreeNodes keep their level (depth) in the DomTree. By having this information always available, it is possible to speedup and simplify findNearestCommonDominator and certain dominance queries.
In the future, level information will be also needed to perform incremental updates.
My testing doesn't show any noticeable performance differences after applying this patch. There may be some improvements when other passes are thought to use the level information.
Reviewers: dberlin, sanjoy, chandlerc, grosser
Reviewed By: dberlin
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D34548
llvm-svn: 306892
Summary:
DFS InOut numbers currently get eagerly computer upon DomTree construction. They are only needed to answer dome dominance queries and they get invalidated by updates and recalculations. Because of that, it is faster in practice to compute them lazily when they are actually needed.
Clang built without this patch takes 6m 45s to boostrap on my machine, and with the patch applied 6m 38s.
Reviewers: sanjoy, dberlin, chandlerc
Reviewed By: dberlin
Subscribers: davide, llvm-commits
Differential Revision: https://reviews.llvm.org/D34296
llvm-svn: 306778
Summary:
This patch is part of 3 patches that together form a single patch, but must be introduced in stages in order not to break things.
The way that LLVM interprets DW_OP_plus in DIExpression nodes is basically that of the DW_OP_plus_uconst operator since LLVM expects an unsigned constant operand. This unnecessarily restricts the DW_OP_plus operator, preventing it from being used to describe the evaluation of runtime values on the expression stack. These patches try to align the semantics of DW_OP_plus and DW_OP_minus with that of the DWARF definition, which pops two elements off the expression stack, performs the operation and pushes the result back on the stack.
This is done in three stages:
• The first patch (LLVM) adds support for DW_OP_plus_uconst.
• The second patch (Clang) contains changes all its uses from DW_OP_plus to DW_OP_plus_uconst.
• The third patch (LLVM) changes the semantics of DW_OP_plus and DW_OP_minus to be in line with its DWARF meaning. This patch includes the bitcode upgrade from legacy DIExpressions.
Patch by Sander de Smalen.
Reviewers: echristo, pcc, aprantl
Reviewed By: aprantl
Subscribers: fhahn, javed.absar, aprantl, llvm-commits
Differential Revision: https://reviews.llvm.org/D33894
llvm-svn: 305386
Previously, the matching was done incorrectly for the case where
operands for FCmpInst and SelectInst were in opposite order.
Patch by Andrei Elovikov.
Differential Revision: https://reviews.llvm.org/D33185
llvm-svn: 305308
Summary:
This patch is part of 3 patches that together form a single patch, but must be introduced in stages in order not to break things.
The way that LLVM interprets DW_OP_plus in DIExpression nodes is basically that of the DW_OP_plus_uconst operator since LLVM expects an unsigned constant operand. This unnecessarily restricts the DW_OP_plus operator, preventing it from being used to describe the evaluation of runtime values on the expression stack. These patches try to align the semantics of DW_OP_plus and DW_OP_minus with that of the DWARF definition, which pops two elements off the expression stack, performs the operation and pushes the result back on the stack.
This is done in three stages:
• The first patch (LLVM) adds support for DW_OP_plus_uconst.
• The second patch (Clang) contains changes all its uses from DW_OP_plus to DW_OP_plus_uconst.
• The third patch (LLVM) changes the semantics of DW_OP_plus and DW_OP_minus to be in line with its DWARF meaning. This patch includes the bitcode upgrade from legacy DIExpressions.
Patch by Sander de Smalen.
Reviewers: pcc, echristo, aprantl
Reviewed By: aprantl
Subscribers: fhahn, aprantl, javed.absar, llvm-commits
Differential Revision: https://reviews.llvm.org/D33892
llvm-svn: 305304
clang-format (https://reviews.llvm.org/D33932) to keep primary headers
at the top and handle new utility headers like 'gmock' consistently with
other utility headers.
No other change was made. I did no manual edits, all of this is
clang-format.
This should allow other changes to have more clear and focused diffs,
and is especially motivated by moving some headers into more focused
libraries.
llvm-svn: 304786
This removes a quadratic behavior in assert-enabled builds.
GVN propagates the equivalence from a condition into the blocks guarded by the
condition. E.g. for 'if (a == 7) { ... }', 'a' will be replaced in the block
with 7. It does this by replacing all the uses of 'a' that are dominated by
the true edge.
For a switch with N cases and U uses of the value, this will mean N * U calls
to 'dominates'. Asserting isSingleEdge in 'dominates' make this N^2 * U
because this function checks for the uniqueness of the edge. I.e. traverses
each edge between the SwitchInst's block and the cases.
The change removes the assert and makes 'dominates' works correctly in the
presence of non-unique edges.
This brings build time down by an order of magnitude for an input that has
~10k cases in a switch statement.
Differential Revision: https://reviews.llvm.org/D33584
llvm-svn: 304721
I've taken the approach from the LoopInfo test:
* Rather than running in the pass manager just build the analyses manually
* Split out the common parts (makeLLVMModule, runWithDomTree) into helpers
Differential Revision: https://reviews.llvm.org/D33617
llvm-svn: 304061
block.
This allows writing much more natural and readable range based for loops
directly over the PHI nodes. It also takes advantage of the same tricks
for terminating the sequence as the hand coded versions.
I've replaced one example of this mostly to showcase the difference and
I've added a unit test to make sure the facilities really work the way
they're intended. I want to use this inside of SimpleLoopUnswitch but it
seems generally nice.
Differential Revision: https://reviews.llvm.org/D33533
llvm-svn: 303964
getParamAlignment expects an argument number, not an AttributeList
index.
Johan Englan, who works on LDC, found this bug and told me about it off
list.
llvm-svn: 303458
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
r271020 added an early out to skip the signed multiply portion of ConstantRange::multiply. The comment says we don't need to do signed multiply if the range is only positive numbers, but the implemented check only ensures that the start of the range is positive. It doesn't look at the end of the range.
This patch checks the end of the range instead. Because Upper is one more than the end we have to see if its positive or if its one past the last positive number.
llvm-svn: 302717
Use variadic templates instead of relying on <cstdarg> + sentinel.
This enforces better type checking and makes code more readable.
Differential Revision: https://reviews.llvm.org/D32541
llvm-svn: 302571
Summary:
Following up on Sanjay's suggetion in D32955, move this functionality
into ShuffleVectornstruction.
Reviewers: spatel, RKSimon
Reviewed By: RKSimon
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D32956
llvm-svn: 302420
Summary:
This frees up one slot in the HandleBaseKind enum, which I will use
later to add a new kind of value handle. The size of the
HandleBaseKind enum is important because we store a HandleBaseKind in
the low two bits of a (in the worst case) 4 byte aligned pointer.
Reviewers: davide, chandlerc
Subscribers: mcrosier, llvm-commits
Differential Revision: https://reviews.llvm.org/D32634
llvm-svn: 301809
This broke the Clang build. (Clang-side patch missing?)
Original commit message:
> [IR] Make add/remove Attributes use AttrBuilder instead of
> AttributeList
>
> This change cleans up call sites and avoids creating temporary
> AttributeList objects.
>
> NFC
llvm-svn: 301712
Matt Arsenault