Bug fix for PR37445. The underlying problem and its fix are similar to PR37808.
The bug lies in MemorySSAUpdater::getPreviousDefRecursive(), where PhiOps is
computed before the call to tryRemoveTrivialPhi() and it ends up being out of
date, pointing to stale data. We have now turned each of the PhiOps into a
TrackingVH<MemoryAccess>.
Differential Revision: https://reviews.llvm.org/D49425
llvm-svn: 337680
Summary:
Pretty mechanical follow-up for D49196.
As microarchitecture.pdf notes, "20 AMD Ryzen pipeline",
"20.8 Register renaming and out-of-order schedulers":
The integer register file has 168 physical registers of 64 bits each.
The floating point register file has 160 registers of 128 bits each.
"20.14 Partial register access":
The processor always keeps the different parts of an integer register together.
...
An instruction that writes to part of a register will therefore have a false dependence
on any previous write to the same register or any part of it.
Reviewers: andreadb, courbet, RKSimon, craig.topper, GGanesh
Reviewed By: GGanesh
Subscribers: gbedwell, llvm-commits
Differential Revision: https://reviews.llvm.org/D49393
llvm-svn: 337676
Bug fix for PR36787. When reasoning if it's safe to hoist a load we
want to make sure that the defining memory access dominates the new
insertion point of the hoisted instruction. safeToHoistLdSt calls
firstInBB(InsertionPoint,DefiningAccess) which returns false if
InsertionPoint == DefiningAccess, and therefore it falsely thinks
it's safe to hoist.
Differential Revision: https://reviews.llvm.org/D49555
llvm-svn: 337674
a call, and then again as a return.
Also added a comment to try and explain better why we would be doing
what we're doing when hardening the (non-call) returns.
llvm-svn: 337673
This specifically covers different ways of making indirect calls and
jumps. There are some bugs in SLH that I will be fixing in subsequent
patches where the diff in the generated instructions makes the bug fix
much more clear, so just checking in a baseline of this test to start.
I'm also going to be adding direct mitigation for variant 1.2 which this
file very specifically tests in the various forms it can arise on x86.
Again, the diff to the generated instructions should make the change for
that much more clear, so having the test as a baseline seems useful.
llvm-svn: 337672
This provides an overview of the algorithm used to harden specific
loads. It also brings this our terminology further in line with
hardening rather than checking.
Differential Revision: https://reviews.llvm.org/D49583
llvm-svn: 337667
This seems to be a net improvement. There's still an issue under avx512f where we have a 512-bit vpaddd, but not vpmaddwd so we end up doing two 256-bit vpmaddwds and inserting the results before a 512-bit vpaddd. It might be better to do two 512-bits paddds with zeros in the upper half. Same number of instructions, but breaks a dependency.
llvm-svn: 337656
Summary:
This takes 22ms out of ~20s compiling sqlite3.c because we call it
for every unit of compilation and every pass.
Reviewers: paquette, anemet
Subscribers: mehdi_amini, llvm-commits
Differential Revision: https://reviews.llvm.org/D49586
llvm-svn: 337654
This is used on an extract vector element index which is most cases is going to be an i32 or i64 and the element will be a valid element number. But it is possible to construct IR with a larger type and large out of range value.
llvm-svn: 337652
Summary: The original text was lifted from the MCA README. I re-ran the dot-product example and updated the output seen in the docs. I also added a few paragraphs discussing the instruction issued and retired histograms, as well as discussing the register file stats.
Reviewers: andreadb, RKSimon, courbet, gbedwell, filcab
Reviewed By: andreadb
Subscribers: tschuett
Differential Revision: https://reviews.llvm.org/D49614
llvm-svn: 337648
This is a follow-up to the rL335185. Those commit adds some WrapperPat
patterns for microMIPS target. But declaration of the WrapperPat class
is under the NotInMicroMips predicate and microMIPS patterns cannot be
selected because predicate (Subtarget->inMicroMipsMode()) &&
(!Subtarget->inMicroMipsMode()) is always false.
This change move out the WrapperPat class declaration from the
NotInMicroMips predicate and enables microMIPS WrapperPat patterns.
Differential revision: https://reviews.llvm.org/D49533
llvm-svn: 337646
If an error occurs and we write it to stderr, it could appear
before we wrote the mangled name which we're undecorating.
By flushing stdout first, we ensure that the messages are always
sequenced in the correct order.
llvm-svn: 337645
Summary:
This flag is used when emitting debug info and is needed to initialize subprogram and member function attributes (function options) for Codeview. These function options are used to create an accurate compiler type for UDT symbols (class/struct/union) from PDBs.
It is not easy to determine if a C++ record is trivial or not based on the current DICompositeType flags and other accessible debug information from Codeview. For example, without this flag the metadata for a non-trivial C++ record with user-defined ctor and a trivial one with a defaulted ctor are the same.
struct S { S(); }
struct S { S() = default; }
This change introduces a new DI flag and corresponding clang::CXXRecordDecl::isTrivial method to set the flag in the frontend.
Reviewers: rnk, zturner, llvm-commits, dblaikie, aleksandr.urakov, deadalnix
Reviewed By: rnk
Subscribers: asmith, probinson, aprantl, JDevlieghere
Differential Revision: https://reviews.llvm.org/D45122
llvm-svn: 337641
We tested different cap values with a recent commit of Chromium. Our results show that the 32-byte cap yields the smallest binary and all the caps yield similar performance.
Based on the results, we propose to change the cap value to 32-byte.
Patch by Zhaomo Yang!
Differential Revision: https://reviews.llvm.org/D49405
llvm-svn: 337622
This reapplies commit r337489 reverted by r337541
Additionally, this commit contains a speculative fix to the issue reported in r337541
(the report does not contain an actionable reproducer, just a stack trace)
llvm-svn: 337606
A DAG-NOT-DAG is a CHECK-DAG group, X, followed by a CHECK-NOT group,
N, followed by a CHECK-DAG group, Y. Let y be the initial directive
of Y. This patch makes the following changes to the behavior:
1. Directives in N can no longer match within part of Y's match
range just because y happens not to be the earliest match from
Y. Specifically, this patch withdraws N's search range end
from y's match range start to Y's match range start.
2. y can no longer match within X's match range, where a y match
produced a reordering complaint, which is thus no longer
possible. Specifically, this patch withdraws y's search range
start from X's permitted range start to X's match range end,
which was already the search range start for other members of
Y.
Both of these changes can only increase the number of test passes: #1
constrains the ability of CHECK-NOTs to match, and #2 expands the
ability of CHECK-DAGs to match without complaints.
These changes are based on discussions at:
<http://lists.llvm.org/pipermail/llvm-dev/2018-May/123550.html>
<https://reviews.llvm.org/D47106>
which conclude that:
1. These changes simplify the FileCheck conceptual model. First,
it makes search ranges for DAG-NOT-DAG more consistent with
other cases. Second, it was confusing that y was treated
differently from the rest of Y.
2. These changes add theoretical use cases for DAG-NOT-DAG that
had no obvious means to be expressed otherwise. We can justify
the first half of this assertion with the observation that
these changes can only increase the number of test passes.
3. Reordering detection for DAG-NOT-DAG had no obvious real
benefit.
We don't have evidence from real uses cases to help us debate
conclusions #2 and #3, but #1 at least seems intuitive.
Reviewed By: probinson
Differential Revision: https://reviews.llvm.org/D48986
llvm-svn: 337605
Summary:
Add basic support for --rename-section=old=new to llvm-objcopy.
A full replacement for GNU objcopy requires also modifying flags (i.e. --rename-section=old=new,flag1,flag2); I'd like to keep that in a separate change to keep this simple.
Reviewers: jakehehrlich, alexshap
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D49576
llvm-svn: 337604
Incidentally all allocations that we currently perform were
properly aligned, but this was only an accident.
Thanks to Erik Pilkington for catching this.
llvm-svn: 337596
deprecating SymbolResolver and AsynchronousSymbolQuery.
Both lookup overloads take a VSO search order to perform the lookup. The first
overload is non-blocking and takes OnResolved and OnReady callbacks. The second
is blocking, takes a boolean flag to indicate whether to wait until all symbols
are ready, and returns a SymbolMap. Both overloads take a RegisterDependencies
function to register symbol dependencies (if any) on the query.
llvm-svn: 337595
This discards the unresolved symbols set and returns the flags map directly
(rather than mutating it via the first argument).
The unresolved symbols result made it easy to chain lookupFlags calls, but such
chaining should be rare to non-existant (especially now that symbol resolvers
are being deprecated) so the simpler method signature is preferable.
llvm-svn: 337594
A search order is a list of VSOs to be searched linearly to find symbols. Each
VSO now has a search order that will be used when fixing up definitions in that
VSO. Each VSO's search order defaults to just that VSO itself.
This is a first step towards removing symbol resolvers from ORC altogether. In
practice symbol resolvers tended to be used to implement a search order anyway,
sometimes with additional programatic generation of symbols. Now that VSOs
support programmatic generation of definitions via fallback generators, search
orders provide a cleaner way to achieve the desired effect (while removing a lot
of boilerplate).
llvm-svn: 337593
Ideally our ISD node types going into the isel table would have types consistent with their instruction domain. This prevents us having to duplicate patterns with different types for the same instruction.
Unfortunately, it seems our shuffle combining is currently relying on this a little remove some bitcasts. This seems to enable some switching between shufps and shufd. Hopefully there's some way we can address this in the combining.
Differential Revision: https://reviews.llvm.org/D49280
llvm-svn: 337590
CombineTo is most useful when you need to replace multiple results, avoid the worklist management, or you need to something else after the combine, etc. Otherwise you should be able to just return the new node and let DAGCombiner go through its usual worklist code.
All of the places changed in this patch look to be standard cases where we should be able to use the more stand behavior of just returning the new node.
Differential Revision: https://reviews.llvm.org/D49569
llvm-svn: 337589
Alexandros Lamprineas