The current full unroll cost model does a symbolic evaluation of the loop up to a fixed limit. That symbolic evaluation currently simplifies to constants, but we can generalize to arbitrary Values using the InstructionSimplify infrastructure at very low cost.
By itself, this enables some simplifications, but it's mainly useful when combined with the branch simplification over in D102928.
Differential Revision: https://reviews.llvm.org/D102934
- Currently, before printing a label in MCSymbol.cpp (MCSymbol::print), the current code "validates" the label that is to be printed.
- If it fails the validation step, then it prints the label within double quotes.
- However, the validation is provided as a virtual function in MCAsmInfo.h (i.e. isAcceptableChar() function). So we can override this for the AD_HLASM dialect in SystemZMCAsmInfo.cpp.
Reviewed By: uweigand
Differential Revision: https://reviews.llvm.org/D103091
Global values imply flags such as readable, writable, executable for the
sections that they will be placed in. Currently MC places all such
entries into the same section, using the first set of flags seen. This
can lead to situations in LTO where a writable global is placed in the
same named section as a readable global from another file, and the
section may not be marked writable.
D72194 ensures that mergeable globals with explicit sections are placed
in separate sections with compatible entry size, by emitting the
`unique` assembly syntax where appropriate. This change extends that
approach to include section flags, so that globals with different
section flags are emitted in separate unique sections.
Differential revision: https://reviews.llvm.org/D100944
Now that vmulh can be selected, this adds the MVE patterns to make it
legal and generate instructions.
Differential Revision: https://reviews.llvm.org/D88011
I really needed this, like, factually, yesterday,
when verifying dependency breaking idioms for AMD Zen 3 scheduler model.
Consider the following example:
```
$ ./bin/llvm-exegesis --mode=inverse_throughput --snippets-file=/tmp/snippet.s --num-repetitions=1000000 --repetition-mode=duplicate
Check generated assembly with: /usr/bin/objdump -d /tmp/snippet-4a7e50.o
---
mode: inverse_throughput
key:
instructions:
- 'VPXORYrr YMM0 YMM0 YMM0'
config: ''
register_initial_values: []
cpu_name: znver3
llvm_triple: x86_64-unknown-linux-gnu
num_repetitions: 1000000
measurements:
- { key: inverse_throughput, value: 0.31025, per_snippet_value: 0.31025 }
error: ''
info: ''
assembled_snippet: C5FDEFC0C5FDEFC0C5FDEFC0C5FDEFC0C5FDEFC0C5FDEFC0C5FDEFC0C5FDEFC0C5FDEFC0C5FDEFC0C5FDEFC0C5FDEFC0C5FDEFC0C5FDEFC0C5FDEFC0C5FDEFC0C3
...
```
What does it tell us?
So wait, it can only execute ~3 x86 AVX YMM PXOR zero-idioms per cycle?
That doesn't seem right. That's even less than there are pipes supporting this type of op.
Now, second example:
```
$ ./bin/llvm-exegesis --mode=inverse_throughput --snippets-file=/tmp/snippet.s --num-repetitions=1000000 --repetition-mode=loop
Check generated assembly with: /usr/bin/objdump -d /tmp/snippet-2418b5.o
---
mode: inverse_throughput
key:
instructions:
- 'VPXORYrr YMM0 YMM0 YMM0'
config: ''
register_initial_values: []
cpu_name: znver3
llvm_triple: x86_64-unknown-linux-gnu
num_repetitions: 1000000
measurements:
- { key: inverse_throughput, value: 1.00011, per_snippet_value: 1.00011 }
error: ''
info: ''
assembled_snippet: 49B80800000000000000C5FDEFC0C5FDEFC04983C0FF75F2C3
...
```
Now that's just worse. Due to the looping, the throughput completely plummeted,
and now we can only do a single instruction/cycle!?
That's not great.
And final example:
```
$ ./bin/llvm-exegesis --mode=inverse_throughput --snippets-file=/tmp/snippet.s --num-repetitions=1000000 --repetition-mode=loop --loop-body-size=1000
Check generated assembly with: /usr/bin/objdump -d /tmp/snippet-c402e2.o
---
mode: inverse_throughput
key:
instructions:
- 'VPXORYrr YMM0 YMM0 YMM0'
config: ''
register_initial_values: []
cpu_name: znver3
llvm_triple: x86_64-unknown-linux-gnu
num_repetitions: 1000000
measurements:
- { key: inverse_throughput, value: 0.167087, per_snippet_value: 0.167087 }
error: ''
info: ''
assembled_snippet: 49B80800000000000000C5FDEFC0C5FDEFC04983C0FF75F2C3
...
```
So if we merge the previous two approaches, do duplicate this single-instruction snippet 1000x
(loop-body-size/instruction count in snippet), and run a loop with 1000 iterations
over that duplicated/unrolled snippet, the measured throughput goes through the roof,
up to 5.9 instructions/cycle, which finally tells us that this idiom is zero-cycle!
Reviewed By: courbet
Differential Revision: https://reviews.llvm.org/D102522
I cannot find documentation on this CPU, and it
is not supported by the Arm Compiler 5 product either.
It was likely a mistake or a different name for the
"ep9312", which is an Arm based Cirrus Logic chip.
Reviewed By: peter.smith
Differential Revision: https://reviews.llvm.org/D103024
This patch introduces new operations on jitlink::Blocks: setMutableContent,
getMutableContent and getAlreadyMutableContent. The setMutableContent method
will set the block content data and size members and flag the content as
mutable. The getMutableContent method will return a mutable copy of the existing
content value, auto-allocating and populating a new mutable copy if the existing
content is marked immutable. The getAlreadyMutableMethod asserts that the
existing content is already mutable and returns it.
setMutableContent should be used when updating the block with totally new
content backed by mutable memory. It can be used to change the size of the
block. The argument value should *not* be shared with any other block.
getMutableContent should be used when clients want to modify the existing
content and are unsure whether it is mutable yet.
getAlreadyMutableContent should be used when clients want to modify the existing
content and know from context that it must already be immutable.
These operations reduce copy-modify-update boilerplate and unnecessary copies
introduced when clients couldn't me sure whether the existing content was
mutable or not.
This makes it possible for targets to define their own MCObjectFileInfo.
This MCObjectFileInfo is then used to determine things like section alignment.
This is a follow up to D101462 and prepares for the RISCV backend defining the
text section alignment depending on the enabled extensions.
Reviewed By: MaskRay
Differential Revision: https://reviews.llvm.org/D101921
Don't run tasks until their corresponding thread has been added to the running
threads vector. This is an extention to fda4300da8, which doesn't seem to have
been enough to fix the synchronization issues on its own.
The implementation and intent behind freeing the triple string here is the same
as LLVMGetDefaultTargetTriple (and any other owned c string returned from the C
API), so we should use LLVMDisposeMessage for to free the string for
consistency.
Patch by Mats Larsen -- thanks Mats!
Reviewed By: lhames
Differential Revision: https://reviews.llvm.org/D102957
Now that gtest has been updated to 1.10 which supports GTEST_SKIP, we can use
that over return;
Patch by Mats Larsen. Thanks Mats!
Reviewed By: lhames, ikudrin
Differential Revision: https://reviews.llvm.org/D102710
[Debugify][Original DI] Test dbg var loc preservation
This is an improvement of [0]. This adds checking of
original llvm.dbg.values()/declares() instructions in
optimizations.
We have picked a real issue that has been found with
this (actually, picked one variable location missing
from [1] and resolved the issue), and the result is
the fix for that -- D100844.
Before applying the D100844, using the options from [0]
(but with this patch applied) on the compilation of GDB 7.11,
the final HTML report for the debug-info issues can be found
at [1] (please scroll down, and look for
"Summary of Variable Location Bugs"). After applying
the D100844, the numbers has improved a bit -- please take
a look into [2].
[0] https://llvm.org/docs/HowToUpdateDebugInfo.html#\
test-original-debug-info-preservation-in-optimizations
[1] https://djolertrk.github.io/di-check-before-adce-fix/
[2] https://djolertrk.github.io/di-check-after-adce-fix/
Differential Revision: https://reviews.llvm.org/D100845
The Unit test was failing because the pass from the test that
modifies the IR, in its runOnFunction() didn't return 'true',
so the expensive-check configuration triggered an assertion.
We can't declare unique_function that has in its arguments a reference to
a template type with an incomplete argument.
For instance, we can't declare unique_function<void(SmallVectorImpl<A>&)>
when A is forward declared.
This is because SFINAE will trigger a hard error in this case, when instantiating
IsSizeLessThanThresholdT with the incomplete type.
This patch specialize AdjustedParamT for references to remove this error.
Committed on behalf of: @math-fehr (Fehr Mathieu)
Reviewed By: DaniilSuchkov, yrouban
Previously APFloat::convertToDouble may be called only for APFloats that
were built using double semantics. Other semantics like single precision
were not allowed although corresponding numbers could be converted to
double without loss of precision. The similar restriction applied to
APFloat::convertToFloat.
With this change any APFloat that can be precisely represented by double
can be handled with convertToDouble. Behavior of convertToFloat was
updated similarly. It make the conversion operations more convenient and
adds support for formats like half and bfloat.
Differential Revision: https://reviews.llvm.org/D102671
This is an improvement of [0]. This adds checking of
original llvm.dbg.values()/declares() instructions in
optimizations.
We have picked a real issue that has been found with
this (actually, picked one variable location missing
from [1] and resolved the issue), and the result is
the fix for that -- D100844.
Before applying the D100844, using the options from [0]
(but with this patch applied) on the compilation of GDB 7.11,
the final HTML report for the debug-info issues can be found
at [1] (please scroll down, and look for
"Summary of Variable Location Bugs"). After applying
the D100844, the numbers has improved a bit -- please take
a look into [2].
[0] https://llvm.org/docs/HowToUpdateDebugInfo.html\
[1] https://djolertrk.github.io/di-check-before-adce-fix/
[2] https://djolertrk.github.io/di-check-after-adce-fix/
Differential Revision: https://reviews.llvm.org/D100845
For source-based coverage, the frontend sets the counter IDs and the
constraints of counter IDs is not defined. For e.g., the Rust frontend
until recently had a reserved counter #0
(https://github.com/rust-lang/rust/pull/83774). Rust coverage
instrumentation also creates counters on edges in addition to basic
blocks. Some functions may have more counters than regions.
This breaks an assumption in CoverageMapping.cpp where the number of
counters in a function is assumed to be bounded by the number of
regions:
Counts.assign(Record.MappingRegions.size(), 0);
This assumption causes CounterMappingContext::evaluate() to fail since
there are not enough counter values created in the above call to
`Counts.assign`. Consequently, some uncovered functions are not
reported in coverage reports.
This change walks a Function's CoverageMappingRecord to find the maximum
counter ID, and uses it to initialize the counter array when instrprof
records are missing for a function in sparse profiles.
Differential Revision: https://reviews.llvm.org/D101780
The operation of some VP intrinsics do/will not map to regular
instruction opcodes. Returning 'None' seems more intuitive here than
'Instruction::Call'.
Reviewed By: frasercrmck
Differential Revision: https://reviews.llvm.org/D102778
Currently all AA analyses marked as preserved are stateless, not taking
into account their dependent analyses. So there's no need to mark them
as preserved, they won't be invalidated unless their analyses are.
SCEVAAResults was the one exception to this, it was treated like a
typical analysis result. Make it like the others and don't invalidate
unless SCEV is invalidated.
Reviewed By: asbirlea
Differential Revision: https://reviews.llvm.org/D102032
Bot has error "Failed to create target from default triple: Unable to
find target for this triple (no targets are registered)", likely because
we only initialized the native target, not the registered target if it's
different.
https://lab.llvm.org/buildbot/#/builders/86/builds/13664
This reverts commit 5c291482ec.
unittests/Passes/CMakeFiles/PassesBindingsTests.dir/PassBuilderBindingsTest.cpp.o: In function `PassBuilderCTest::SetUp()':
PassBuilderBindingsTest.cpp:(.text._ZN16PassBuilderCTest5SetUpEv[_ZN16PassBuilderCTest5SetUpEv]+0x28): undefined reference to `LLVMInitializeARMTargetInfo'
Bot has error "Failed to create target from default triple: Unable to
find target for this triple (no targets are registered)", likely because
we only initialized the native target, not the registered target if it's
different.
https://lab.llvm.org/buildbot/#/builders/86/builds/13664
Similar versions of these already exist, this effectively just just
factors them out into STLExtras. I plan to use these in future patches.
Differential Revision: https://reviews.llvm.org/D100672
This patch contains the bare minimum to run the new Pass Manager from the LLVM-C APIs. It does not feature PGOOptions, PassPlugins or Debugify in its current state. Bugzilla: PR48499
Reviewed By: aeubanks
Differential Revision: https://reviews.llvm.org/D102136
This patch contains the bare minimum to run the new Pass Manager from the LLVM-C APIs. It does not feature PGOOptions, PassPlugins or Debugify in its current state. Bugzilla: PR48499
Reviewed By: aeubanks
Differential Revision: https://reviews.llvm.org/D102136
We've accumulated a scary amount of local patches to this directory. I
tried to merge them all, but if your favorite change is missing please
reapply it manually (and send it upstream).
This is separate from (but builds on) the support added in ec6b71df70 for
emitting LinkGraphs in the context of an active materialization. This commit
makes LinkGraphs a first-class data structure with features equivalent to
object files within ObjectLinkingLayer.
Philip Reames