Depending on who you ask, PGO grants a 15%-25% improvement in build
times when using clang. Sadly, hooking everything up properly to
generate a profile and apply it to clang isn't always straightforward.
This script (and the accompanying docs) aim to make this process easier;
ideally, a single invocation of the given script.
In terms of testing, I've got a cronjob on my Debian box that's meant to
run this a few times per week, and I tried manually running it on a puny
Gentoo box I have (four whole Atom cores!). Nothing obviously broke.
¯\_(ツ)_/¯
I don't know if we have a Python style guide, so I just shoved this
through yapf with all the defaults on.
Finally, though the focus is clang at the moment, the hope is that this
is easily applicable to other LLVM-y tools with minimal effort (e.g.
lld, opt, ...). Hence, this lives in llvm/utils and tries to be somewhat
ambiguous about naming.
Differential Revision: https://reviews.llvm.org/D53598
llvm-svn: 345427
Summary:
The pfm counters are now in the ExegesisTarget rather than the
MCSchedModel (PR39165).
This also compresses the pfm counter tables (PR37068).
Reviewers: RKSimon, gchatelet
Subscribers: mgrang, llvm-commits
Differential Revision: https://reviews.llvm.org/D52932
llvm-svn: 345243
(Relands r344930, reverted in r344935, and now hopefully fixed for
Windows.)
While this change specifically targets FileCheck, it affects any tool
using the same SourceMgr facilities.
Previously, -color was documented in FileCheck's -help output, but
-color had no effect. Now, -color obeys its documentation: it forces
colors to be used in FileCheck diagnostics even when stderr is not a
terminal.
-color is especially helpful when combined with FileCheck's -v, which
can produce a long series of diagnostics that you might wish to pipe
to a pager, such as less -R. The WithColor extensions here will also
help to clean up color usage in FileCheck's annotated dump of input,
which is proposed in D52999.
Reviewed By: JDevlieghere, zturner
Differential Revision: https://reviews.llvm.org/D53419
llvm-svn: 345202
Add a list of benchmarks, applications and algorithms which are under
discussion to be added to the test-suite.
The initial list includes the the benchmarks mentioned at
https://llvm.org/PR34216, missing SPEC benchmarks, some image processing
algorithms and a few others. The bug tracker only allows adding to the
discussion, not removing, commenting, adding details to individual
benchmarks.
The first proposal was to add these benchmark into the test-suite
repository, but after a discussion, adding it to llvm/docs/Proposals
seem more appropriate. One advantage is that llvm.org will have a
browsable web page with these suggestions.
Suggested-by: Hal Finkel
Differential Revision: https://reviews.llvm.org/D46714
llvm-svn: 345074
While this change specifically targets FileCheck, it affects any tool
using the same SourceMgr facilities.
Previously, -color was documented in FileCheck's -help output, but
-color had no effect. Now, -color obeys its documentation: it forces
colors to be used in FileCheck diagnostics even when stderr is not a
terminal.
-color is especially helpful when combined with FileCheck's -v, which
can produce a long series of diagnostics that you might wish to pipe
to a pager, such as less -R. The WithColor extensions here will also
help to clean up color usage in FileCheck's annotated dump of input,
which is proposed in D52999.
Reviewed By: JDevlieghere
Differential Revision: https://reviews.llvm.org/D53419
llvm-svn: 344930
Allows to disable direct TLS segment access (%fs or %gs). GCC supports
a similar flag, it can be useful in some circumstances, e.g. when a thread
context block needs to be updated directly from user space. More info
and specific use cases: https://bugs.llvm.org/show_bug.cgi?id=16145
There is another revision for clang as well.
Related: D53102
All X86 CodeGen tests appear to pass:
```
[46/47] Running lit suite /SourceCache/llvm-trunk-8.0/test/CodeGen
Testing Time: 23.17s
Expected Passes : 3801
Expected Failures : 15
Unsupported Tests : 8021
```
Reviewed by: Craig Topper.
Patch by nruslan (Ruslan Nikolaev).
Differential Revision: https://reviews.llvm.org/D53103
llvm-svn: 344723
Returning the error to clients provides an opportunity to introduce readers to
the Expected and Error APIs and makes the tutorial more useful as a starting
point for a real JIT class, while only slightly complicating the code.
llvm-svn: 344720
Summary:
We try to recover gracefully on instructions that would crash the
program.
This includes some refactoring of runMeasurement() implementations.
Reviewers: gchatelet
Subscribers: tschuett, llvm-commits
Differential Revision: https://reviews.llvm.org/D53371
llvm-svn: 344695
Summary:
These new intrinsics have the semantics of the `minimum` and `maximum`
operations specified by the latest draft of IEEE 754-2018. Unlike
llvm.minnum and llvm.maxnum, these new intrinsics propagate NaNs and
always treat -0.0 as less than 0.0. `minimum` and `maximum` lower
directly to the existing `fminnan` and `fmaxnan` ISel DAG nodes. It is
safe to reuse these DAG nodes because before this patch were only
emitted in situations where there were known to be no NaN arguments or
where NaN propagation was correct and there were known to be no zero
arguments. I know of only four backends that lower fminnan and
fmaxnan: WebAssembly, ARM, AArch64, and SystemZ, and each of these
lowers fminnan and fmaxnan to instructions that are compatible with
the IEEE 754-2018 semantics.
Reviewers: aheejin, dschuff, sunfish, javed.absar
Subscribers: kristof.beyls, dexonsmith, kristina, llvm-commits
Differential Revision: https://reviews.llvm.org/D52764
llvm-svn: 344437
Summary:
This is a step towards fixing PR38048.
Note that right now the measurements are given per instruction. We'll
need to give measurements a per code snippet and update the analysis (PR38731).
Reviewers: gchatelet
Subscribers: tschuett, llvm-commits
Differential Revision: https://reviews.llvm.org/D52041
llvm-svn: 342947
In my original diff I missed #include "llvm/System/Thing.h" and forgot to update a
reference to .inc files a few lines down. This patch corrects these things as
they were missed in revision 342500.
llvm-svn: 342705
Summary:
Some lines have a hit counter where they should not have one.
For example, in C++, some cleanup is adding at the end of a scope represented by a '}'.
So such a line has a hit counter where a user expects to not have one.
The goal of the patch is to add this information in DILocation which is used to get the covered lines in GCOVProfiling.cpp.
A following patch in clang will add this information when generating IR (https://reviews.llvm.org/D49916).
Reviewers: marco-c, davidxl, vsk, javed.absar, rnk
Reviewed By: rnk
Subscribers: eraman, xur, danielcdh, aprantl, rnk, dblaikie, #debug-info, vsk, llvm-commits, sylvestre.ledru
Tags: #debug-info
Differential Revision: https://reviews.llvm.org/D49915
llvm-svn: 342631
System Library has been a long deprecated term along with the path lib/System, having been superseded/renamed
to the Support Library a long time ago. These patches reflect those changes in documentation as well as
update some outdated examples and provide context to the origin of the Support Library.
Differential Revision: https://reviews.llvm.org/D52107
llvm-svn: 342500
Summary:
Remove note about summary being ignored. Update to reflect the
fact that summary is now parsed by llvm-as.
While here, fix one summary format that changed since the initial
implementation.
Reviewers: dexonsmith
Subscribers: inglorion, llvm-commits
Differential Revision: https://reviews.llvm.org/D51540
llvm-svn: 342479
add a tool to generate symbol remapping files.
Summary:
The new tool llvm-cxxmap builds a symbol mapping table from a file containing
a description of partial equivalences to apply to mangled names and files
containing old and new symbol tables.
Reviewers: davidxl
Subscribers: mgorny, llvm-commits
Differential Revision: https://reviews.llvm.org/D51470
llvm-svn: 342168
The assertion in MCCodeView.cpp was resolved in r340878.
This reverts both r340905 and r340836, making benchmarks build by
default everywhere.
llvm-svn: 341716
Load Hardening.
Wires up the existing pass to work with a proper IR attribute rather
than just a hidden/internal flag. The internal flag continues to work
for now, but I'll likely remove it soon.
Most of the churn here is adding the IR attribute. I talked about this
Kristof Beyls and he seemed at least initially OK with this direction.
The idea of using a full attribute here is that we *do* expect at least
some forms of this for other architectures. There isn't anything
*inherently* x86-specific about this technique, just that we only have
an implementation for x86 at the moment.
While we could potentially expose this as a Clang-level attribute as
well, that seems like a good question to defer for the moment as it
isn't 100% clear whether that or some other programmer interface (or
both?) would be best. We'll defer the programmer interface side of this
for now, but at least get to the point where the feature can be enabled
without relying on implementation details.
This also allows us to do something that was really hard before: we can
enable *just* the indirect call retpolines when using SLH. For x86, we
don't have any other way to mitigate indirect calls. Other architectures
may take a different approach of course, and none of this is surfaced to
user-level flags.
Differential Revision: https://reviews.llvm.org/D51157
llvm-svn: 341363
implementing the proposed mitigation technique described in the original
design document.
The idea is to check after calls that the return address used to arrive
at that location is in fact the correct address. In the event of
a mis-predicted return which reaches a *valid* return but not the
*correct* return, this will detect the mismatch much like it would
a mispredicted conditional branch.
This is the last published attack vector that I am aware of in the
Spectre v1 space which is not mitigated by SLH+retpolines. However,
don't read *too* much into that: this is an area of ongoing research
where we expect more issues to be discovered in the future, and it also
makes no attempt to mitigate Spectre v4. Still, this is an important
completeness bar for SLH.
The change here is of course delightfully simple. It was predicated on
cutting support for post-instruction symbols into LLVM which was not at
all simple. Many thanks to Hal Finkel, Reid Kleckner, and Justin Bogner
who helped me figure out how to do a bunch of the complex changes
involved there.
Differential Revision: https://reviews.llvm.org/D50837
llvm-svn: 341358
- Remove duplication: Both TestingGuide and TestSuiteMakefileGuide
would give a similar overview over the test-suite.
- Present cmake/lit as the default/normal way of running the test-suite:
- Move information about the cmake/lit testsuite into the new
TestSuiteGuide.rst file. Mark the remaining information in
TestSuiteMakefilesGuide.rst as deprecated.
- General simplification and shorting of language.
- Remove paragraphs about tests known to fail as everything should pass
nowadays.
- Remove paragraph about zlib requirement; it's not required anymore
since we copied a zlib source snapshot into the test-suite.
- Remove paragraph about comparison with "native compiler". Correctness is
always checked against reference outputs nowadays.
- Change cmake/lit quickstart section to recommend `pip` for installing
lit and use `CMAKE_C_COMPILER` and a cache file in the example as that
is what most people will end up doing anyway. Also a section about
compare.py to quickstart.
- Document `Bitcode` and `MicroBenchmarks` directories.
- Add section with commonly used cmake configuration options.
- Add section about showing and comparing result files via compare.py.
- Add section about using external benchmark suites.
- Add section about using custom benchmark suites.
- Add section about profile guided optimization.
- Add section about cross-compilation and running on external devices.
Differential Revision: https://reviews.llvm.org/D51465
llvm-svn: 341260
This patch introduces the following changes to the DispatchStatistics view:
* DispatchStatistics now reports the number of dispatched opcodes instead of
the number of dispatched instructions.
* The "Dynamic Dispatch Stall Cycles" table now also reports the percentage of
stall cycles against the total simulated cycles.
This change allows users to easily compare dispatch group sizes with the
processor DispatchWidth.
Before this change, it was difficult to correlate the two numbers, since
DispatchStatistics view reported numbers of instructions (instead of opcodes).
DispatchWidth defines the maximum size of a dispatch group in terms of number of
micro opcodes.
The other change introduced by this patch is related to how DispatchStage
generates "instruction dispatch" events.
In particular:
* There can be multiple dispatch events associated with a same instruction
* Each dispatch event now encapsulates the number of dispatched micro opcodes.
The number of micro opcodes declared by an instruction may exceed the processor
DispatchWidth. Therefore, we cannot assume that instructions are always fully
dispatched in a single cycle.
DispatchStage knows already how to handle instructions declaring a number of
opcodes bigger that DispatchWidth. However, DispatchStage always emitted a
single instruction dispatch event (during the first simulated dispatch cycle)
for instructions dispatched.
With this patch, DispatchStage now correctly notifies multiple dispatch events
for instructions that cannot be dispatched in a single cycle.
A few views had to be modified. Views can no longer assume that there can only
be one dispatch event per instruction.
Tests (and docs) have been updated.
Differential Revision: https://reviews.llvm.org/D51430
llvm-svn: 341055
This patch adds two new fields to the perf report generated by the SummaryView.
Fields are now logically organized into two small groups; only the second group
contains throughput indicators.
Example:
```
Iterations: 100
Instructions: 300
Total Cycles: 414
Total uOps: 700
Dispatch Width: 4
uOps Per Cycle: 1.69
IPC: 0.72
Block RThroughput: 4.0
```
This patch also updates the docs for llvm-mca.
Due to the nature of this change, several tests in the tools/llvm-mca directory
were affected, and had to be updated using script `update_mca_test_checks.py`.
llvm-svn: 340946
The problems with benchmark build should be fixed now, but Windows
buildbots still run into errors seemingly because of the bug in
clang-cl. Because of that, benchmark shouldn't be built on Windows at
this point.
llvm-svn: 340905
This patch pulls google/benchmark v1.4.1 into the LLVM tree so that any
project could use it for benchmark generation. A dummy benchmark is
added to `llvm/benchmarks/DummyYAML.cpp` to validate the correctness of
the build process.
The current version does not utilize LLVM LNT and LLVM CMake
infrastructure, but that might be sufficient for most users. Two
introduced CMake variables:
* `LLVM_INCLUDE_BENCHMARKS` (`ON` by default) generates benchmark
targets
* `LLVM_BUILD_BENCHMARKS` (`OFF` by default) adds generated
benchmark targets to the list of default LLVM targets (i.e. if `ON`
benchmarks will be built upon standard build invocation, e.g. `ninja` or
`make` with no specific targets)
List of modifications:
* `BENCHMARK_ENABLE_TESTING` is disabled
* `BENCHMARK_ENABLE_EXCEPTIONS` is disabled
* `BENCHMARK_ENABLE_INSTALL` is disabled
* `BENCHMARK_ENABLE_GTEST_TESTS` is disabled
* `BENCHMARK_DOWNLOAD_DEPENDENCIES` is disabled
Original discussion can be found here:
http://lists.llvm.org/pipermail/llvm-dev/2018-August/125023.html
Reviewed by: dberris, lebedev.ri
Subscribers: ilya-biryukov, ioeric, EricWF, lebedev.ri, srhines,
dschuff, mgorny, krytarowski, fedor.sergeev, mgrang, jfb, llvm-commits
Differential Revision: https://reviews.llvm.org/D50894
llvm-svn: 340809
Before this patch, the SchedulerStatistics only printed the maximum number of
buffer entries consumed in each scheduler's queue at a given point of the
simulation.
This patch restructures the reported table, and adds an extra field named
"Average number of used buffer entries" to it.
This patch also uses different colors to help identifying bottlenecks caused by
high scheduler's buffer pressure.
llvm-svn: 340746
This is a bit awkward in a handful of places where we didn't even have
an instruction and now we have to see if we can build one. But on the
whole, this seems like a win and at worst a reasonable cost for removing
`TerminatorInst`.
All of this is part of the removal of `TerminatorInst` from the
`Instruction` type hierarchy.
llvm-svn: 340701
Most users won't have to worry about this as all of the
'getOrInsertFunction' functions on Module will default to the program
address space.
An overload has been added to Function::Create to abstract away the
details for most callers.
This is based on https://reviews.llvm.org/D37054 but without the changes to
make passing a Module to Function::Create() mandatory. I have also added
some more tests and fixed the LLParser to accept call instructions for
types in the program address space.
Reviewed By: bjope
Differential Revision: https://reviews.llvm.org/D47541
llvm-svn: 340519
This adds the plumbing for the Tiny code model for the AArch64 backend. This,
instead of loading addresses through the normal ADRP;ADD pair used in the Small
model, uses a single ADR. The 21 bit range of an ADR means that the code and
its statically defined symbols need to be within 1MB of each other.
This makes it mostly interesting for embedded applications where we want to fit
as much as we can in as small a space as possible.
Differential Revision: https://reviews.llvm.org/D49673
llvm-svn: 340397
well as MIR parsing support for `MCSymbol` `MachineOperand`s.
The only real way to test pre- and post-instruction symbol support is to
use them in operands, so I ended up implementing that within the patch
as well. I can split out the operand support if folks really want but it
doesn't really seem worth it.
The functional implementation of pre- and post-instruction symbols is
now *completely trivial*. Two tiny bits of code in the (misnamed)
AsmPrinter. It should be completely target independent as well. We emit
these exactly the same way as we emit basic block labels. Most of the
code here is to give full dumping, MIR printing, and MIR parsing support
so that we can write useful tests.
The MIR parsing of MC symbol operands still isn't 100%, as it forces the
symbols to be non-temporary and non-local symbols with names. However,
those names often can encode most (if not all) of the special semantics
desired, and unnamed symbols seem especially annoying to serialize and
de-serialize. While this isn't perfect or full support, it seems plenty
to write tests that exercise usage of these kinds of operands.
The MIR support for pre-and post-instruction symbols was quite
straightforward. I chose to print them out in an as-if-operand syntax
similar to debug locations as this seemed the cleanest way and let me
use nice introducer tokens rather than inventing more magic punctuation
like we use for memoperands.
However, supporting MIR-based parsing of these symbols caused me to
change the design of the symbol support to allow setting arbitrary
symbols. Without this, I don't see any reasonable way to test things
with MIR.
Differential Revision: https://reviews.llvm.org/D50833
llvm-svn: 339962
Clarify that you should not introduce trailing whitespace when making a commit and that you should not remove trailing whitespace that's unrelated to code you are changing or are about to change. Then clarified the developer policy around what is considered an obvious whitespace commit.
llvm-svn: 339455
Summary:
Add a CommandGuide for llvm-objdump summarizing its usage along with some
general context.
Reviewers: beanz
Reviewed By: beanz
Subscribers: Eugene.Zelenko, llvm-commits
Differential Revision: https://reviews.llvm.org/D50034
llvm-svn: 339250
The sphinx build bot is erroring on these examples for some unknown
reason, and really the dso_local doesn't seem to be relevant to the
example in any way so its cleaner to omit it. And now they will look
a bit more like other (successful) IR examples.
llvm-svn: 338998
highlighting syntax.
Most of them already were like this, and the Sphinx runs on the docs
build bot seems to be substantially more picky and/or not have support
for a bunch of the syntax here. Hopefully this will let it progress past
this.
My previous attempt to fix the syntax made the `opt` tool happy, but no
idea what the Sphinx stuff is really looking for, and the fact that
other blocks already just use `text` led me to this solution.
llvm-svn: 338983
Notably, just close two of the debug info metadata nodes early rather
than leaving them open with `...` which won't ever lex correctly. And
add the missing `:` on the count labels.
Slowly progressing through all of the warnings on the documentation
build bot. Sorry to do this one commit at a time, but despite my best
efforts I can't trigger these errors locally.
llvm-svn: 338982
Sphinx syntax highlighter.
This example also doesn't really make sense. There is no control flow or
clarification of what the `Safe:` block exists to do... If we want
examples here, we should make them much more clear in addition to making
them well formed IR sequences.
llvm-svn: 338981
This appears to produce a warning on the docs build bot. It doesn't
reproduce for me, likely because I have a newer (or more full featured)
pygments install.
llvm-svn: 338978
Sphinx.
We think the bot is updated now, so trying this again. I'm landing it
(with permission) as Michael is at a con at the moment.
Actual patch largely by Michael Spencer.
Differential Revision: https://reviews.llvm.org/D44910
llvm-svn: 338977
This patch is a follow-up to r338702.
We don't need to use a map to model the wait/ready/issued sets. It is much more
efficient to use a vector instead.
This patch gives us an average 7.5% speedup (on top of the ~12% speedup obtained
after r338702).
llvm-svn: 338883
This patch replaces all the remaining occurrences of string "MCA" with
":program:`llvm-mca`". Somehow I missed those strings when I committed r338394.
This patch also improves section "Instruction Dispatch".
llvm-svn: 338881
Summary:
This patch mostly copies the existing Instruction Flow, and stage descriptions
from the mca README. I made a few text tweaks, but no semantic changes,
and made reference to the "default pipeline." I also removed the internals
references (e.g., reference to class names and header files). I did leave the
LSUnit name around, but only as an abbreviated word for the load-store unit.
Reviewers: andreadb, courbet, RKSimon, gbedwell, filcab
Reviewed By: andreadb
Subscribers: tschuett, jfb, llvm-commits
Differential Revision: https://reviews.llvm.org/D49692
llvm-svn: 338319
This makes it easier for someone to copy-paste this line, change the path, and run the command.
Differential Revision: https://reviews.llvm.org/D49201
llvm-svn: 338254
This should make the semantics of DIExpressions within llvm.dbg.{addr,
declare, value} easier to understand.
Differential Revision: https://reviews.llvm.org/D49572
llvm-svn: 338182
In light of the recent changes to SmallVector in r335421, r337514, and
r337820, document its advantages over std::vector (see r175906 and
r266909).
Also add a release note.
https://reviews.llvm.org/D49748
llvm-svn: 338071
Violating the invariants specified by attributes is undefined behavior.
Maybe we could use poison instead for some of the parameter attributes,
but I don't think it's worthwhile.
Differential Revision: https://reviews.llvm.org/D49041
llvm-svn: 337947
This new JIT event listener supports generating profiling data for
the linux 'perf' profiling tool, allowing it to generate function and
instruction level profiles.
Currently this functionality is not enabled by default, but must be
enabled with LLVM_USE_PERF=yes. Given that the listener has no
dependencies, it might be sensible to enable by default once the
initial issues have been shaken out.
I followed existing precedent in registering the listener by default
in lli. Should there be a decision to enable this by default on linux,
that should probably be changed.
Please note that until https://reviews.llvm.org/D47343 is resolved,
using this functionality with mcjit rather than orcjit will not
reliably work.
Disregarding the previous comment, here's an example:
$ cat /tmp/expensive_loop.c
bool stupid_isprime(uint64_t num)
{
if (num == 2)
return true;
if (num < 1 || num % 2 == 0)
return false;
for(uint64_t i = 3; i < num / 2; i+= 2) {
if (num % i == 0)
return false;
}
return true;
}
int main(int argc, char **argv)
{
int numprimes = 0;
for (uint64_t num = argc; num < 100000; num++)
{
if (stupid_isprime(num))
numprimes++;
}
return numprimes;
}
$ clang -ggdb -S -c -emit-llvm /tmp/expensive_loop.c -o
/tmp/expensive_loop.ll
$ perf record -o perf.data -g -k 1 ./bin/lli -jit-kind=mcjit /tmp/expensive_loop.ll 1
$ perf inject --jit -i perf.data -o perf.jit.data
$ perf report -i perf.jit.data
- 92.59% lli jitted-5881-2.so [.] stupid_isprime
stupid_isprime
main
llvm::MCJIT::runFunction
llvm::ExecutionEngine::runFunctionAsMain
main
__libc_start_main
0x4bf6258d4c544155
+ 0.85% lli ld-2.27.so [.] do_lookup_x
And line-level annotations also work:
│ for(uint64_t i = 3; i < num / 2; i+= 2) {
│1 30: movq $0x3,-0x18(%rbp)
0.03 │1 38: mov -0x18(%rbp),%rax
0.03 │ mov -0x10(%rbp),%rcx
│ shr $0x1,%rcx
3.63 │ ┌──cmp %rcx,%rax
│ ├──jae 6f
│ │ if (num % i == 0)
0.03 │ │ mov -0x10(%rbp),%rax
│ │ xor %edx,%edx
89.00 │ │ divq -0x18(%rbp)
│ │ cmp $0x0,%rdx
0.22 │ │↓ jne 5f
│ │ return false;
│ │ movb $0x0,-0x1(%rbp)
│ │↓ jmp 73
│ │ }
3.22 │1 5f:│↓ jmp 61
│ │ for(uint64_t i = 3; i < num / 2; i+= 2) {
Subscribers: mgorny, llvm-commits
Differential Revision: https://reviews.llvm.org/D44892
llvm-svn: 337789
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
For the most part, these changes were from the RFC. I made a few minor
word/structure changes, but nothing significant. I also regenerated the
example output, and adjusted the text accordingly.
Differential Revision: https://reviews.llvm.org/D49527
llvm-svn: 337496
Add some quick words for unroll and jam to the list of passes and add
unroll_and_jam metadata to the language ref.
Differential Revision: https://reviews.llvm.org/D49349
llvm-svn: 337448
Summary:
Updated and reorganized. Made the following additions:
1) How to see if ld.gold is installed, and whether it is the current
default.
2) How to install ld.gold as the default or alternatively use
-fuse-ld=gold.
3) Move the part about installing the newly built ld-new as the default
to the prior section and how to use --enable-gold=default to do it
automatically on install.
4) Add a note about ld.bfd supporting plugins but indicate that it is
not tested by the LLVM project and gold is the recommended linker for
use with the gold plugin.
Fixes PR32760.
Reviewers: davide
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D49490
llvm-svn: 337404
a Spectre v1 mitigation.
This was initially posted w/ the patch implementing this, got some basic
review there. Also, it is generated from a the Google doc that I shared
as part of the Speculative Load Hardening RFC and which has seen pretty
widespread review at this point.
However, as the patches are landing in LLVM, I wanted to land the docs
as well. But it seemed like a bad idea to have them in the same commit
in case of reverts or other things. So the docs are split out here.
Thanks for all the review so far, and further review and improvements to
the documentation here welcome. Please feel free to keep hammering on
the code review or Google document.
Note that this is a markdown document which Sphinx doesn't yet process.
But we can add support for that after and this should get picked up
(and I'm preparing patches for that). Also, this gets the document
itself into a nice shared place where we can iterate on it.
Differential Revision: https://reviews.llvm.org/D49433
llvm-svn: 337391
We need to explicitly state what happens when an invariant promised by
load metadata is violated at runtime, since it's come up repeatedly.
It's possible we want to specify that the result of the load is poison
in some cases, rather than undefined behavior, if the constraint is
violated. That would allow preserving the metadata when the load is
hoisted, but doesn't allow propagating metadata based on control flow.
We currently do transforms based on control flow for nonnull metadata
(in PromoteMemToReg).
Differential Revision: https://reviews.llvm.org/D47854
llvm-svn: 337325
Clarify that violating nnan and ninf can lead to undefined behavior.
This allows more aggressive optimizations based on those assumptions.
Differential Revision: https://reviews.llvm.org/D47963
llvm-svn: 337323
We're going to work on this in a separate review focusing more on documenting
the View and probably removing some of the less-interesting/less-useful pieces.
This reverts r337219,337225
llvm-svn: 337295
As discussed here:
http://lists.llvm.org/pipermail/llvm-dev/2018-May/123292.htmlhttp://lists.llvm.org/pipermail/llvm-dev/2018-July/124400.html
We want to add rotate intrinsics because the IR expansion of that pattern is 4+ instructions,
and we can lose pieces of the pattern before it gets to the backend. Generalizing the operation
by allowing 2 different input values (plus the 3rd shift/rotate amount) gives us a "funnel shift"
operation which may also be a single hardware instruction.
Initially, I thought we needed to define new DAG nodes for these ops, and I spent time working
on that (much larger patch), but then I concluded that we don't need it. At least as a first
step, we have all of the backend support necessary to match these ops...because it was required.
And shepherding these through the IR optimizer is the primary concern, so the IR intrinsics are
likely all that we'll ever need.
There was also a question about converting the intrinsics to the existing ROTL/ROTR DAG nodes
(along with improving the oversized shift documentation). Again, I don't think that's strictly
necessary (as the test results here prove). That can be an efficiency improvement as a small
follow-up patch.
So all we're left with is documentation, definition of the IR intrinsics, and DAG builder support.
Differential Revision: https://reviews.llvm.org/D49242
llvm-svn: 337221
This patch introduces a brief description of the components of MCA. The main
focus is on Views. This is a work in progress, and more descriptions will be
introduced later. I want to flesh-out the Views section more and provide a
detailed description of eventing in MCA. Eventually a brief code example of a
View should accompany the description.
Also, we should consider moving the MCA internals guide elsewhere at some point.
llvm-svn: 337219
As suggested in the review for r337007, this makes cfi-verify abort on unsupported targets instead of producing incorrect results. It also updates the design document to reflect this.
Differential Revision: https://reviews.llvm.org/D49304
llvm-svn: 337181
-v prints all directive pattern matches.
-vv additionally prints info that might be noise to users but that can
be helpful to FileCheck developers.
To maximize code reuse and to make diagnostics more consistent, this
patch also adjusts and extends some of the existing diagnostics.
CHECK-NOT failures now report variables uses. Many more diagnostics
now report the check prefix and kind of directive.
Reviewed By: probinson
Differential Revision: https://reviews.llvm.org/D47114
llvm-svn: 336967
That is, make CHECK-DAG skip matches that overlap the matches of any
preceding consecutive CHECK-DAG directives. This change makes
CHECK-DAG more consistent with other directives, and there is evidence
it makes CHECK-DAG more intuitive and less error-prone. See the RFC
discussion starting at:
http://lists.llvm.org/pipermail/llvm-dev/2018-May/123010.html
Moreover, this behavior enables CHECK-DAG groups for unordered,
non-unique strings or patterns. For example, it is useful for
verifying output or logs from a parallel program, such as the OpenMP
runtime.
This patch also implements the command-line option
-allow-deprecated-dag-overlap, which reverts CHECK-DAG to the old
overlapping behavior. This option should not be used in new tests.
It is meant only for the existing tests that are broken by this change
and that need time to update.
See the following bugzilla issue for tracking of such tests:
https://bugs.llvm.org/show_bug.cgi?id=37532
Patches to add -allow-deprecated-dag-overlap to those tests will
follow immediately.
Reviewed By: probinson
Differential Revision: https://reviews.llvm.org/D47106
llvm-svn: 336847
This reverts commit r306102.
This change was made without any review, and has a couple of issues.
First, AFAIK we do not test the combination of the LLVM gold plugin with
ld.bfd. Second, the change removed documentation for how to build gold
and replaced it with instructions for building ld.bfd.
llvm-svn: 336841
That is, make CHECK-DAG skip matches that overlap the matches of any
preceding consecutive CHECK-DAG directives. This change makes
CHECK-DAG more consistent with other directives, and there is evidence
it makes CHECK-DAG more intuitive and less error-prone. See the RFC
discussion starting at:
http://lists.llvm.org/pipermail/llvm-dev/2018-May/123010.html
Moreover, this behavior enables CHECK-DAG groups for unordered,
non-unique strings or patterns. For example, it is useful for
verifying output or logs from a parallel program, such as the OpenMP
runtime.
This patch also implements the command-line option
-allow-deprecated-dag-overlap, which reverts CHECK-DAG to the old
overlapping behavior. This option should not be used in new tests.
It is meant only for the existing tests that are broken by this change
and that need time to update.
See the following bugzilla issue for tracking of such tests:
https://bugs.llvm.org/show_bug.cgi?id=37532
Patches to add -allow-deprecated-dag-overlap to those tests will
follow immediately.
Reviewed By: probinson
Differential Revision: https://reviews.llvm.org/D47106
llvm-svn: 336830
The aim of this backend is to output everything TableGen knows about
the record set, similarly to the default -print-records backend. But
where -print-records produces output in TableGen's input syntax
(convenient for humans to read), this backend produces it as
structured JSON data, which is convenient for loading into standard
scripting languages such as Python, in order to extract information
from the data set in an automated way.
The output data contains a JSON representation of the variable
definitions in output 'def' records, and a few pieces of metadata such
as which of those definitions are tagged with the 'field' prefix and
which defs are derived from which classes. It doesn't dump out
absolutely every piece of knowledge it _could_ produce, such as type
information and complicated arithmetic operator nodes in abstract
superclasses; the main aim is to allow consumers of this JSON dump to
essentially act as new backends, and backends don't generally need to
depend on that kind of data.
The new backend is implemented as an EmitJSON() function similar to
all of llvm-tblgen's other EmitFoo functions, except that it lives in
lib/TableGen instead of utils/TableGen on the basis that I'm expecting
to add it to clang-tblgen too in a future patch.
To test it, I've written a Python script that loads the JSON output
and tests properties of it based on comments in the .td source - more
or less like FileCheck, except that the CHECK: lines have Python
expressions after them instead of textual pattern matches.
Reviewers: nhaehnle
Reviewed By: nhaehnle
Subscribers: arichardson, labath, mgorny, llvm-commits
Differential Revision: https://reviews.llvm.org/D46054
llvm-svn: 336771
Let's be conservative here; it matches what we actually implemented, and
it should be rare in practice anyway.
Differential Revision: https://reviews.llvm.org/D49042
llvm-svn: 336744
Summary:
Support for this option is needed for building Linux kernel.
This is a very frequently requested feature by kernel developers.
More details : https://lkml.org/lkml/2018/4/4/601
GCC option description for -fdelete-null-pointer-checks:
This Assume that programs cannot safely dereference null pointers,
and that no code or data element resides at address zero.
-fno-delete-null-pointer-checks is the inverse of this implying that
null pointer dereferencing is not undefined.
This feature is implemented in LLVM IR in this CL as the function attribute
"null-pointer-is-valid"="true" in IR (Under review at D47894).
The CL updates several passes that assumed null pointer dereferencing is
undefined to not optimize when the "null-pointer-is-valid"="true"
attribute is present.
Reviewers: t.p.northover, efriedma, jyknight, chandlerc, rnk, srhines, void, george.burgess.iv
Reviewed By: efriedma, george.burgess.iv
Subscribers: eraman, haicheng, george.burgess.iv, drinkcat, theraven, reames, sanjoy, xbolva00, llvm-commits
Differential Revision: https://reviews.llvm.org/D47895
llvm-svn: 336613
In non-zero address spaces, we were reporting that an object at `null`
always occupies zero bytes. This is incorrect in many cases, so just
return `unknown` in those cases for now.
Differential Revision: https://reviews.llvm.org/D48860
llvm-svn: 336611
Summary:
This adds a new -no-weak flag to nm to hide weak symbols in its output.
This also adds a -W alias for this which is analogous to -U.
Patch by Keith Smiley
Reviewers: kastiglione, enderby, compnerd
Reviewed By: kastiglione
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D48751
llvm-svn: 336126
Summary:
This patch introduce new intrinsic -
strip.invariant.group that was described in the
RFC: Devirtualization v2
Reviewers: rsmith, hfinkel, nlopes, sanjoy, amharc, kuhar
Subscribers: arsenm, nhaehnle, JDevlieghere, hiraditya, xbolva00, llvm-commits
Differential Revision: https://reviews.llvm.org/D47103
Co-authored-by: Krzysztof Pszeniczny <krzysztof.pszeniczny@gmail.com>
llvm-svn: 336073
Prior to this change, there was no clean way of getting FileCheck to
check that a line is completely empty. The expected way of using
"CHECK: {{^$}}" does not work because the '^' matches the end of the
previous match (this behaviour may be desirable in certain instances).
For the same reason, "CHECK-NEXT: {{^$}}" will fail when the previous
match was at the end of the line, as the pattern will match there.
Using the recommended [[:space:]] to match an explicit new line could
also match a space, and thus is not always desired. Literal '\n'
matches also do not work. A workaround was suggested in the review, but
it is a little clunky.
This change adds a new directive that behaves the same as CHECK-NEXT,
except that it only matches against empty lines (nothing, not even
whitespace, is allowed). As with CHECK-NEXT, it will fail if more than
one newline occurs before the next blank line. Example usage:
; test.txt
foo
bar
; CHECK: foo
; CHECK-EMPTY:
; CHECK-NEXT: bar
Differential Revision: https://reviews.llvm.org/D28896
Reviewed by: probinson
llvm-svn: 335613
Update AMDGPU assembler syntax behind the code-object-v3 feature:
* Replace/rename most AMDGPU assembler directives/symbols and document them.
* Provide more diagnostics (e.g. values out of range, missing values, repeated
values).
* Provide path for backwards compatibility, even with underlying descriptor
changes.
Differential Revision: https://reviews.llvm.org/D47736
llvm-svn: 335281
and everything that comes with it from implementation
and v3 header files.
Leave definition in v2 header files for backwards
compatibility.
Differential Revision: https://reviews.llvm.org/D48191
llvm-svn: 335267
Summary:
This is essentially a rewrite of the backend which introduces TableGen
base classes GenericEnum, GenericTable, and SearchIndex. They allow
generating custom enums and tables with lookup functions using
separately defined records as the underlying database.
Also added as part of this change:
- Lookup functions may use indices composed of multiple fields.
- Instruction fields are supported similar to Intrinsic fields.
- When the lookup key has contiguous numeric values, the lookup
function will directly index into the table instead of using a binary
search.
The existing SearchableTable functionality is internally mapped to the
new primitives.
Change-Id: I444f3490fa1dbfb262d7286a1660a2c4308e9932
Reviewers: arsenm, tra, t.p.northover
Subscribers: wdng, llvm-commits
Differential Revision: https://reviews.llvm.org/D48013
llvm-svn: 335225
IEEE 754 defines the expected result on overflow. As far as I know,
hardware implementations (of f16), and compiler-rt (__floatuntisf)
correctly return +-Inf on overflow. And I can't think of any useful
transform that would take advantage of overflow being undefined here.
Differential Revision: https://reviews.llvm.org/D47807
llvm-svn: 334777
- Do not emit following assembler directives:
- .hsa_code_object_version
- .hsa_code_object_isa
- .amd_amdgpu_isa
- .amd_amdgpu_hsa_metadata
- .amd_amdgpu_pal_metadata
- Do not emit .note entries
- Cleanup and bring in sync kernel descriptor header file
- Emit kernel descriptor into .rodata with appropriate relocations and
alignments
llvm-svn: 334519
I think we assume poison, not undef, for certain transforms we
currently do. In any case, we should clarify the language here.
(This sort of conversion is undefined behavior according to the C
and C++ standards. And in practice, hardware implementations handle
overflow inconsistently, so it would be difficult to define the
result here.)
Differential Revision: https://reviews.llvm.org/D47851
llvm-svn: 334326
We need to clarify the language here. I think poison makes more sense
than undef, since it's an undefined operation rather than uninitialized
memory. I don't think anything depends on the difference at the moment,
though.
Differential Revision: https://reviews.llvm.org/D47859
llvm-svn: 334325
since couple of months, supports had been enabled for FreeBSD and OpenBSD.
Reviewers: thakis, spatel, dim
Reviewed By: dim
Differential Revision: https://reviews.llvm.org/D47322
llvm-svn: 334207
Summary: It has been deprecated in favor of SETCCCARRY for a year now and isn't used by any in tree backend.
Reviewers: efriedma, craig.topper, dblaikie, bkramer
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D47685
llvm-svn: 333939
Summary:
The new rules are straightforward. The main rules to keep in mind
are:
1. NAME is an implicit template argument of class and multiclass,
and will be substituted by the name of the instantiating def/defm.
2. The name of a def/defm in a multiclass must contain a reference
to NAME. If such a reference is not present, it is automatically
prepended.
And for some additional subtleties, consider these:
3. defm with no name generates a unique name but has no special
behavior otherwise.
4. def with no name generates an anonymous record, whose name is
unique but undefined. In particular, the name won't contain a
reference to NAME.
Keeping rules 1&2 in mind should allow a predictable behavior of
name resolution that is simple to follow.
The old "rules" were rather surprising: sometimes (but not always),
NAME would correspond to the name of the toplevel defm. They were
also plain bonkers when you pushed them to their limits, as the old
version of the TableGen test case shows.
Having NAME correspond to the name of the toplevel defm introduces
"spooky action at a distance" and breaks composability:
refactoring the upper layers of a hierarchy of nested multiclass
instantiations can cause unexpected breakage by changing the value
of NAME at a lower level of the hierarchy. The new rules don't
suffer from this problem.
Some existing .td files have to be adjusted because they ended up
depending on the details of the old implementation.
Change-Id: I694095231565b30f563e6fd0417b41ee01a12589
Reviewers: tra, simon_tatham, craig.topper, MartinO, arsenm, javed.absar
Subscribers: wdng, llvm-commits
Differential Revision: https://reviews.llvm.org/D47430
llvm-svn: 333900
Object FIle Representation
At codegen time this is emitted into the ELF file a pair of symbol indices and a weight. In assembly it looks like:
.cg_profile a, b, 32
.cg_profile freq, a, 11
.cg_profile freq, b, 20
When writing an ELF file these are put into a SHT_LLVM_CALL_GRAPH_PROFILE (0x6fff4c02) section as (uint32_t, uint32_t, uint64_t) tuples as (from symbol index, to symbol index, weight).
Differential Revision: https://reviews.llvm.org/D44965
llvm-svn: 333823
Summary:
They've been deprecated in favor of UADDO/ADDCARRY or USUBO/SUBCARRY for a while.
Target that uses these opcodes are changed in order to ensure their behavior doesn't change.
Reviewers: efriedma, craig.topper, dblaikie, bkramer
Subscribers: jholewinski, arsenm, jyknight, sdardis, nemanjai, nhaehnle, kbarton, fedor.sergeev, asb, rbar, johnrusso, simoncook, jordy.potman.lists, apazos, sabuasal, niosHD, jrtc27, zzheng, edward-jones, mgrang, atanasyan, llvm-commits
Differential Revision: https://reviews.llvm.org/D47422
llvm-svn: 333748
(Relands r333584, reverted in 333592.)
When debugging test failures with -vv (or -v in the case of the
internal shell), this makes it easier to locate the RUN line that
failed. For example, clang's test/Driver/linux-ld.c has 892 total RUN
lines, and clang's test/Driver/arm-cortex-cpus.c has 424 RUN lines
after concatenation for line continuations.
When reading the generated shell script, this also makes it easier to
locate the RUN line that produced each command.
To support reporting RUN line numbers in the case of the internal
shell, this patch extends the internal shell to support the null
command, ":", except pipelines are not supported.
To support reporting RUN line numbers in the case of windows cmd.exe
as the external shell, this patch extends -vv to set "echo on" instead
of "echo off" in bat files. (Support for windows cmd.exe as a lit
external shell will likely be dropped later, but I found out too
late.)
Reviewed By: delcypher, asmith, stella.stamenova, jmorse, lebedev.ri, rnk
Differential Revision: https://reviews.llvm.org/D44598
llvm-svn: 333614
(Relands r330755 (reverted in r330848) with fix for PR37239.)
When debugging test failures with -vv (or -v in the case of the
internal shell), this makes it easier to locate the RUN line that
failed. For example, clang's test/Driver/linux-ld.c has 892 total RUN
lines, and clang's test/Driver/arm-cortex-cpus.c has 424 RUN lines
after concatenation for line continuations.
When reading the generated shell script, this also makes it easier to
locate the RUN line that produced each command.
To support reporting RUN line numbers in the case of the internal
shell, this patch extends the internal shell to support the null
command, ":", except pipelines are not supported.
To support reporting RUN line numbers in the case of windows cmd.exe
as the external shell, this patch extends -vv to set "echo on" instead
of "echo off" in bat files. (Support for windows cmd.exe as a lit
external shell will likely be dropped later, but I found out too
late.)
Reviewed By: delcypher, asmith, stella.stamenova, jmorse, lebedev.ri, rnk
Differential Revision: https://reviews.llvm.org/D44598
llvm-svn: 333584
Summary: It was fully replaced back in 2014, and the implementation was removed 11 months ago by r306797.
Reviewers: hfinkel, chandlerc, whitequark, deadalnix
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D47436
llvm-svn: 333378
Summary:
Implements AsmWriter support for printing the module summary index to
assembly with the format discussed in the RFC "LLVM Assembly format for
ThinLTO Summary".
Implements just enough of the parsing support to recognize and ignore
the summary entries. As agreed in the RFC thread, this will be the
behavior when assembling the IR. A follow on change will implement
parsing/assembling of the summary entries for use by tools that
currently build the summary index from bitcode.
Reviewers: dexonsmith, pcc
Subscribers: inglorion, eraman, steven_wu, dblaikie, llvm-commits
Differential Revision: https://reviews.llvm.org/D46699
llvm-svn: 333335
Summary:
This feature is not needed, but it might be usefull in the future
to use metadata to mark what which function should support it
(and strip it when not).
Reviewers: rsmith, sanjoy, amharc, kuhar
Subscribers: hiraditya, llvm-commits
Differential Revision: https://reviews.llvm.org/D45419
llvm-svn: 332787
Summary:
Minor changes to reflect changes to the code that were not documented:
- `SCUDO_DEFAULT_OPTIONS` compile time way of defining options;
- MIPS added as a supported architecture;
- clarification on how to fully disable the Quarantine;
- rewording in a few places.
Reviewers: alekseyshl, flowerhack
Reviewed By: alekseyshl
Subscribers: sdardis, arichardson, atanasyan, llvm-commits
Differential Revision: https://reviews.llvm.org/D47071
llvm-svn: 332736
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:
This addresses http://llvm.org/PR36790.
The change Deprecates a number of functions and types in
`include/xray/xray_log_interface.h` to recommend using string-based
configuration of XRay through the __xray_log_init_mode(...) function. In
particular, this deprecates the following:
- `__xray_set_log_impl(...)` -- users should instead use the
`__xray_log_register_mode(...)` and `__xray_log_select_mode(...)` APIs.
- `__xray_log_init(...)` -- users should instead use the
`__xray_log_init_mode(...)` function, which also requires using the
`__xray_log_register_mode(...)` and `__xray_log_select_mode(...)`
functionality.
- `__xray::FDRLoggingOptions` -- in following patches, we'll be
migrating the FDR logging implementations (and tests) to use the
string-based configuration. In later stages we'll remove the
`__xray::FDRLoggingOptions` type, and ask users to migrate to using the
string-based configuration mechanism instead.
- `__xray::BasicLoggingOptions` -- same as `__xray::FDRLoggingOptions`,
we'll be removing this type later and instead rely exclusively on the
string-based configuration API.
We also update the documentation to reflect the new advice and remove
some of the deprecated notes.
Reviewers: eizan, kpw, echristo, pelikan
Reviewed By: kpw
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D46173
llvm-svn: 331503
This is a follow-up to r331272.
We've been running doxygen with the autobrief option for a couple of
years now. This makes the \brief markers into our comments
redundant. Since they are a visual distraction and we don't want to
encourage more \brief markers in new code either, this patch removes
them all.
Patch produced by
for i in $(git grep -l '\@brief'); do perl -pi -e 's/\@brief //g' $i & done
https://reviews.llvm.org/D46290
llvm-svn: 331275
See thread "Replacing LLVM_ON_WIN32 with just _WIN32" on llvm-dev and cfe-dev.
I replaced all uses of LLVM_ON_WIN32 with _WIN32 in r331127 (llvm),
r331069 (clang), r329697 (lldb), r329696 (lld), r329696 (clang-tools-extra).
If your out-of-tree program used LLVM_ON_WIN32, just use _WIN32 instead, which
is set at exactly the same time to exactly the same value.
https://reviews.llvm.org/D46264
llvm-svn: 331224
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
When debugging test failures with -vv (or -v in the case of the
internal shell), this makes it easier to locate the RUN line that
failed. For example, clang's test/Driver/linux-ld.c has 892 total RUN
lines, and clang's test/Driver/arm-cortex-cpus.c has 424 RUN lines
after concatenation for line continuations.
When reading the generated shell script, this also makes it easier to
locate the RUN line that produced each command.
To support reporting RUN line numbers in the case of the internal
shell, this patch extends the internal shell to support the null
command, ":", except pipelines are not supported.
Reviewed By: asmith, delcypher
Differential Revision: https://reviews.llvm.org/D44598
llvm-svn: 330755
It used to symlink dsymutil to llvm-dsymutil, but after r327790 llvm's dsymutil
binary is now called dsymutil without prefix.
r327792 then reversed the direction of the symlink if
LLVM_INSTALL_CCTOOLS_SYMLINKS was set, but that looks like a buildfix and not
like something anyone should need.
https://reviews.llvm.org/D45966
llvm-svn: 330727
Summary:
This patch removes references to AliasAnalysisCounter pass from the AliasAnalysis documentation. That pass have been eliminated in 2015, at revision trunk@247167.
Reviewed By: hfinkel
Differential Revision: https://reviews.llvm.org/D45876
llvm-svn: 330590
Summary:
In the course of writing an experimental ANTLR grammar based on this
document, I found three errors in the documented BNF:
SimpleValues of dag type are allowed to have no operands at all after
the initial DagArg specifying the operator. For example, the value
(outs) is extremely common in backends; an example in the test suite
is test/TableGen/AsmVariant.td line 30. But the BNF doesn't allow
DagArgList to expand to the empty string (it must contain at least one
DagArg), and therefore the DagArgList specifying the operands in the
dag-shaped production for SimpleValue should be optional.
In the production for BodyItem with a 'let' and an optional RangeList,
the RangeList should have braces around it if it's present, matching
code such as "let E{7-0} = ..." on test/TableGen/BitsInit.td line 42.
Those braces aren't included in the RangeList nonterminal itself, so
instead they need to be part of the optional segment of the BodyItem
production.
Finally, the identifier after 'defm' should be optional. Again, this
is very common in the real back end .td files; an example in the test
suite is in test/TableGen/defmclass.td line 49.
Reviewers: rengolin, nhaehnle, stoklund
Reviewed By: nhaehnle
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D45818
llvm-svn: 330570
Should be a harmless trimming of trailing whitespace from a
documentation file.
(There are other instances of trailing whitespace in this file alone.
I've only fixed one of them, on the basis that that way the rest are
still available for other people's commit-access tests :-)
llvm-svn: 330567
This was originally committed at rL328921 and reverted at rL329920 to
investigate failures in Chrome. This time I've added to the ReleaseNotes
to warn users of the potential of exposing UB and let me repeat that
here for more exposure:
Optimization of floating-point casts is improved. This may cause surprising
results for code that is relying on undefined behavior. Code sanitizers can
be used to detect affected patterns such as this:
int main() {
float x = 4294967296.0f;
x = (float)((int)x);
printf("junk in the ftrunc: %f\n", x);
return 0;
}
$ clang -O1 ftrunc.c -fsanitize=undefined ; ./a.out
ftrunc.c:5:15: runtime error: 4.29497e+09 is outside the range of
representable values of type 'int'
junk in the ftrunc: 0.000000
Original commit message:
fptosi / fptoui round towards zero, and that's the same behavior as ISD::FTRUNC,
so replace a pair of casts with the equivalent node. We don't have to account for
special cases (NaN, INF) because out-of-range casts are undefined.
Differential Revision: https://reviews.llvm.org/D44909
llvm-svn: 330437
Cameron McInally