Summary:
This allows tools like lld that process relocations
to apply data relocation correctly. This information
is required because relocation are stored as section
offset.
Subscribers: jfb, dschuff, jgravelle-google, aheejin
Differential Revision: https://reviews.llvm.org/D35234
llvm-svn: 307741
The issue is not if the value is pcrel. It is whether we have a
relocation or not.
If we have a relocation, the static linker will select the upper
bits. If we don't have a relocation, we have to do it.
llvm-svn: 307730
Summary:
Custom DFS implementation allows us to skip over certain nodes without adding them to the visited map, which is not easily doable with llvm's dfs iterators. What's more, caching predecessors becomes easy.
This patch implements a single DFS function (template) for both forward and reverse DFS, which should be easier to maintain then separate two ones.
Skipping over nodes based on a predicate will be necessary later to implement incremental updates.
There also seems to be a very slight performance improved when bootstrapping clang with this patch on my machine (3:28s -> 3:26s) .
Reviewers: dberlin, sanjoy, davide, grosser
Reviewed By: dberlin
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D34651
llvm-svn: 307727
OpenCL 2.0 introduces the notion of memory scopes in atomic operations to
global and local memory. These scopes restrict how synchronization is
achieved, which can result in improved performance.
This change extends existing notion of synchronization scopes in LLVM to
support arbitrary scopes expressed as target-specific strings, in addition to
the already defined scopes (single thread, system).
The LLVM IR and MIR syntax for expressing synchronization scopes has changed
to use *syncscope("<scope>")*, where <scope> can be "singlethread" (this
replaces *singlethread* keyword), or a target-specific name. As before, if
the scope is not specified, it defaults to CrossThread/System scope.
Implementation details:
- Mapping from synchronization scope name/string to synchronization scope id
is stored in LLVM context;
- CrossThread/System and SingleThread scopes are pre-defined to efficiently
check for known scopes without comparing strings;
- Synchronization scope names are stored in SYNC_SCOPE_NAMES_BLOCK in
the bitcode.
Differential Revision: https://reviews.llvm.org/D21723
llvm-svn: 307722
Summary:
Patch by Klaus Kretzschmar
We would like to introduce a new type of llvm error handler for handling
bad alloc fault situations. LLVM already provides a fatal error handler
for serious non-recoverable error situations which by default writes
some error information to stderr and calls exit(1) at the end (functions
are marked as 'noreturn').
For long running processes (e.g. a server application), exiting the
process is not an acceptable option, especially not when the system is
in a temporary resource bottleneck with a good chance to recover from
this fault situation. In such a situation you would rather throw an
exception to stop the current compilation and try to overcome the
resource bottleneck. The user should be aware of the problem of throwing
an exception in bad alloc situations, e.g. you must not do any
allocations in the unwind chain. This is especially true when adding
exceptions in existing unfamiliar code (as already stated in the comment
of the current fatal error handler)
So the new handler can also be used to distinguish from general fatal
error situations where recovering is no option. It should be used in
cases where a clean unwind after the allocation is guaranteed.
This patch contains:
- A report_bad_alloc function which calls a user defined bad alloc
error handler. If no user handler is registered the
report_fatal_error function is called. This function is not marked as
'noreturn'.
- A install/restore_bad_alloc_error_handler to install/restore the bad
alloc handler.
- An example (in Mutex.cpp) where the report_bad_alloc function is
called in case of a malloc returns a nullptr.
If this patch gets accepted we would create similar patches to fix
corresponding malloc/calloc usages in the llvm code.
Reviewers: chandlerc, greened, baldrick, rnk
Reviewed By: rnk
Subscribers: llvm-commits, MatzeB
Differential Revision: https://reviews.llvm.org/D34753
llvm-svn: 307673
TreePatternNode considers them to be plain integers but MachineInstr considers
them to be a distinct kind of operand.
The tweak to AArch64InstrInfo.td to produce a simple test case is a NFC for
everything except GlobalISelEmitter (confirmed by diffing the tablegenerated
files). GlobalISelEmitter is currently unable to infer the type of operands in
the Dst pattern from the operands in the Src pattern.
llvm-svn: 307634
This takes memory usage from 5.1GB to 970MB - it could go further by
using a small size of 2 instead of the default of 4, but given the
rather high cost of going over this limit by much, I figured a little
slosh would be worth the ~130MB of memory usage.
& this'll might not be such a big deal if we use a custom slab allocator
for the DenseMaps here anyway
While the vast majority (99.9%) of records use only 1 entry, the tuning
parameter to SmallDenseMap is the the number of buckets, not the number
of entries - so a small size of 1 wasn't useful, even for 1 element, it
would tip over into allocating (much, 64 slots worth) more space - none
of them ended up small.
llvm-svn: 307608
This is part of the continuing effort to increase parity between
LLD and MSVC PDBs. link still doesn't like our PDBs, so the most
obvious thing to check was whether adding an empty publics stream
would get it to do something else. It still fails in the same way
but at least this removes one more variable from the equation.
The next logical step would be to try creating an empty globals
stream.
Differential Revision: https://reviews.llvm.org/D35224
llvm-svn: 307598
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
Reduces llvm-profdata memory usage on a large profile from 7.8GB to 5.1GB.
The ProfData API now supports reporting all the errors/warnings rather
than only the first, though llvm-profdata ignores everything after the
first for now to preserve existing behavior. (if there's a desire for
other behavior, happy to implement that - but might be as well left for
a separate patch)
Reviewers: davidxl
Differential Revision: https://reviews.llvm.org/D35149
llvm-svn: 307516
invalidation of analyses when merging SCCs.
While I've added a bunch of testing of this, it takes something much
more like the inliner to really trigger this as you need to have
partially-analyzed SCCs with updates at just the right time. So I've
added a direct test for this using the inliner and verifying the
domtree. Without the changes here, this test ends up finding a stale
dominator tree.
However, to handle this properly, we need to invalidate analyses
*before* merging the SCCs. After talking to Philip and Sanjoy about this
they convinced me this was the right approach. To do this, we need
a callback mechanism when merging SCCs so we can observe the cycle that
will be merged before the merge happens. This API update ended up being
surprisingly easy.
With this commit, the new PM passes the test-suite again. It hadn't
since MemorySSA was enabled for EarlyCSE as that also will find this bug
very quickly.
llvm-svn: 307498
dependencies between analyses.
This uncovers even more issues with the proxies and the splitting apart
of SCCs which are fixed in this patch. I discovered this while trying to
add more rigorous testing for a change I'm making to the call graph
update invalidation logic.
llvm-svn: 307497
The internal representation has a natural way to handle this and it
seems nicer than having to wrap this in an optional (with its own
separate flag).
This also matches how std::function works.
llvm-svn: 307490
Summary:
We don't want to autocomplete flags whose Flags class has `NoDriverOption` when argv[1] is not `-cc1`.
Another idea for this implementation is to make --autocomplete a cc1
option and handle it in clang Frontend, by porting --autocomplete
handler from Driver to Frontend, so that we can handle Driver options
and CC1 options in unified manner.
Differential Revision: https://reviews.llvm.org/D34770
llvm-svn: 307479
This reverts commit 147f45ff24456aea59575fa4ac16c8fa554df46a.
Revert "Revert "Revert "Revert "Replace trivial use of external rc.exe by writing our own .res file.""""
This reverts commit 61a90a67ed54a1f0dfeab457b65abffa129569e4.
The patches were intially reverted because they were causing a failure
on CrWinClangLLD. Unfortunately, this was done haphazardly and didn't
compile, so the revert was reverted again quickly to fix this. One that
was done, the revert of the revert was itself reverted. This allowed me
to finally fix the actual bug in r307452. This patch re-enables the
code path that had originally been causing the bug, now that it (should)
be fixed.
llvm-svn: 307460
Summary:
The original cvtres.exe sets the high bit when an identifier offset
points to a string. Even though this is not mentioned in the spec, and
in fact does not seem to cause errors with most cases, for some reason
this causes a failure in Chromium where the new resource file is not
verified as a new version. This patch sets this high bit flag, and also
adds a test case to check that the output of our library is always
identical to original cvtres.
Reviewers: zturner, ruiu
Subscribers: llvm-commits, hiraditya
Differential Revision: https://reviews.llvm.org/D35099
llvm-svn: 307452
Summary: For interative sample-pgo, if a hot call site is inlined in the profiling binary, we should inline it in before profile annotation in the backend. Before that, the compile phase first collects all GUIDs that needs to be imported and creates virtual "hot" call edge in the summary. However, "hot" is not good enough to guarantee the callsites get inlined. This patch introduces "critical" call edge, and assign much higher importing threshold for those edges.
Reviewers: tejohnson
Reviewed By: tejohnson
Subscribers: sanjoy, mehdi_amini, llvm-commits, eraman
Differential Revision: https://reviews.llvm.org/D35096
llvm-svn: 307439
Summary:
For SamplePGO + ThinLTO, because profile annotation is done twice at both PrepareForThinLTO pipeline and backend compiler, the following changes are needed at the PrepareForThinLTO phase to ensure the IR is not changed dramatically. Otherwise the profile annotation will be inaccurate in the backend compiler.
* disable hot-caller heuristic
* disable loop unrolling
* disable indirect call promotion
This will unblock the new PM testing for sample PGO (tools/clang/test/CodeGen/pgo-sample-thinlto-summary.c), which will be covered in another cfe patch.
Reviewers: chandlerc, tejohnson, davidxl
Reviewed By: tejohnson
Subscribers: sanjoy, mehdi_amini, Prazek, inglorion, llvm-commits
Differential Revision: https://reviews.llvm.org/D34895
llvm-svn: 307437
A couple of things were different about our generated PDBs.
1) We were outputting the wrong Version on the PDB Stream.
The version we were setting was newer than what MSVC is setting.
It's not clear what the implications are, but we change LLD
to use PdbImplVC70, as MSVC does.
2) For the optional debug stream indices in the DBI Stream, we
were outputting 0 to mean "the stream is not present". MSVC
outputs uint16_t(-1), which is the "correct" way to specify
that a stream is not present. So we fix that as well.
3) We were setting the PDB Stream signature to 0. This is supposed
to be the result of calling time(nullptr). Although this leads
to non-deterministic builds, a better way to solve that is by
having a command line option explicitly for generating a
reproducible build, and have the default behavior of lld-link
match the default behavior of link.
To test this, I'm making use of the new and improved `pdb diff`
sub command. To make it suitable for writing tests against, I had
to modify the diff subcommand slightly to print less verbose output.
Previously it would always print | <column> | <value1> | <value2> |
which is quite verbose, and the values are fragile. All we really
want to know is "did we produce the same value as link?" So I added
command line options to print a single character representing the
result status (different, identical, equivalent), and another to
hide the value display. Note that just inspecting the diff output
used to write the test, you can see some things that are obviously
wrong. That is just reflective of the fact that this is the state
of affairs today, not that we're asserting that this is "correct".
We can use this as a starting point to discover differences, fix
them, and update the test.
Differential Revision: https://reviews.llvm.org/D35086
llvm-svn: 307422
We're getting to the point that some MS tools (e.g. DIA) can recognize
our PDBs but others (e.g. link.exe) cannot. I think the way forward is
to improve our tooling to help us find differences more easily. For
example, if we can compile the same program with clang-cl and cl and
have a tool tell us all the places where the PDBs differ, this could
tell us what we're doing wrong. It's tricky though, because there are a
lot of "benign" differences in a PDB. For example, if the string table
in one PDB consists of "foo" followed by "bar" and in the other PDB it
consists of "bar" followed by "foo", this is not necessarily a critical
difference, as long as the uses of these strings also refer to the
correct location. On the other hand, if the second PDB doesn't even
contain the string "foo" at all, this is a critical difference.
diff mode has been in llvm-pdbutil for quite a while, but because of the
above challenge along with some others, it's been hard to make it
useful. I think this patch addresses that. It looks for all the same
things, but it now prints the output in tabular format (carefully
formatted and aligned into tables and fields), and it highlights
critical differences in red, non-critical differences in yellow, and
identical fields in green. This makes it easy to spot the places we
differ, and the general concept of outputting arbitrary fields in
tabular format can be extended to provide analysis into many of the
different types of information that show up in a PDB.
Differential Revision: https://reviews.llvm.org/D35039
llvm-svn: 307421
Based strictly on the name, this seems to have something to do
width edit & continue. The goal of this patch has nothing to do
with supporting edit and continue though. msvc link.exe writes
very basic information into this area even when *not* compiling
with support for E&C, and so the goal here is to bring lld-link
to parity. Since we cannot know what assumptions standard tools
make about the content of PDB files, we need to be as close as
possible.
This ECNames data structure is a standard PDB string hash table.
link.exe puts a single string into this hash table, which is the
full path to the PDB file on disk. It then references this string
from the module descriptor for the compiler generated `* Linker *`
module.
With this patch, lld-link will generate the exact same sequence of
bytes as MSVC link for this subsection for a given object file
input (as reported by `llvm-pdbutil bytes -ec`).
llvm-svn: 307356
When scavenging for a use in instruction MI, we will reload after
that instruction and hence cannot spill uses/defs of this instruction.
This fixes http://llvm.org/PR33687
llvm-svn: 307352
Contrary to the stepForward()/stepBackward() method accumulate() doesn't
have a direction as defs, uses and clobbers all have the same effect.
Also improve the documentation comment.
llvm-svn: 307351
This patch updates the ORC layers and utilities to return and propagate
llvm::Errors where appropriate. This is necessary to allow ORC to safely handle
error cases in cross-process and remote JITing.
llvm-svn: 307350
Model weakly defined symbols as symbols that are both
exports and imported and marked as weak. Local references
to the symbols refer to the import but the linker can
resolve this to the weak export if not strong symbol
is found at link time.
Differential Revision: https://reviews.llvm.org/D35029
llvm-svn: 307348
Adds loop expansions for known-size and unknown-sized memcpy calls, allowing the
target to provide the operand types through TTI callbacks. The default values
for the TTI callbacks use int8 operand types and matches the existing behaviour
if they aren't overridden by the target.
Differential revision: https://reviews.llvm.org/D32536
llvm-svn: 307346
The patch is to adjust the strategy of frequency based consthoisting:
Previously when the candidate block has the same frequency with the existing
blocks containing a const, it will not hoist the const to the candidate block.
For that case, now we change the strategy to hoist the const if only existing
blocks have more than one block member. This is helpful for reducing code size.
Differential Revision: https://reviews.llvm.org/D35084
llvm-svn: 307328