Sometimes people get minimal crash reports after a UBSAN incident. This change
tags each trap with an integer representing the kind of failure encountered,
which can aid in tracking down the root cause of the problem.
There is one result per lookup symbol, so we have to advance the result iterator no matter whether it's NULL or not.
MissingSymbols variable is unused.
Reviewed By: lhames
Differential Revision: https://reviews.llvm.org/D91707
Distinguish objects by target properties address size, endian and machine architecture. So far we only
support x86-64 (ELFCLASS64, ELFDATA2LSB, EM_X86_64).
Reviewed By: lhames
Differential Revision: https://reviews.llvm.org/D90860
Currently in some places we use signed type to represent size of an access and put explicit casts from unsigned to signed.
For example: int64_t EarlierSize = int64_t(Loc.Size.getValue());
Even though it doesn't loos bits (immidiatly) it may overflow and we end up with negative size. Potentially that cause later code to work incorrectly. A simple expample is a check that size is not negative.
I think it would be safer and clearer if we use unsigned type for the size and handle it appropriately.
Reviewed By: fhahn
Differential Revision: https://reviews.llvm.org/D92648
Don't produce or expect any output from the infinite looping test -
doing so is a recipe for racey flakyness without a longer timeout to
ensure the output is received first, even though that doesn't seem
integral/important to the test. Instead have a plain, no output infinite
loop and check that that is caught and handled.
If for some reason the output is valuable for test coverage - the
timeout should be increased from 1 second to give the process time to
output the text, flush, and for that text to be received and buffered
before the test is timed out.
The NPM runs loop passes on loops in forward program order instead of
the legacy PM's reverse program order, causing some debug output to be
in a different order.
Don't know why under Sanitizer build(asan/msan/ubsan), the `std::unordered_map<string, ...>`'s output order is reversed, make the regression test failed.
This change creates a workaround by using sorted container to make the output deterministic.
Reviewed By: hoy, wenlei
Differential Revision: https://reviews.llvm.org/D92816
Instruction darn was introduced in ISA 3.0. It means 'Deliver A Random
Number'. The immediate number L means:
- L=0, the number is 32-bit (higher 32-bits are all-zero)
- L=1, the number is 'conditioned' (processed by hardware to reduce bias)
- L=2, the number is not conditioned, directly from noise source
GCC implements them in three separate intrinsics: __builtin_darn,
__builtin_darn_32 and __builtin_darn_raw. This patch implements the
same intrinsics. And this change also addresses Bugzilla PR39800.
Reviewed By: steven.zhang
Differential Revision: https://reviews.llvm.org/D92465
The -enable-new-pm=1 translation caused loop-vectorize to run on all
functions, then instcombine, rather than all passes on one function then
the next. This caused the output of -debug-only and -print-after to be
interleaved in an unexpected way.
The NPM processes loops in forward program order, whereas the legacy PM
processes them in reverse program order. No reason to test both PMs
here, so just stick to the NPM.
The -loop-flatten legacy pass preserves loop analyses. The legacy PM
will check all passes that preserve loop analyses that they preserve
LCSSA. This implicitly involves running -loop-simplify. The test
shouldn't depend on verify flags being set in order to run
-loop-simplify, so explicitly add it. The new PM ends up not running it
otherwise.
Summary: The imm operands of some instructions are not defined accurately in td.
This is a small patch to correct these definitions.
Reviewed By: steven.zhang
Differential Revision: https://reviews.llvm.org/D91603
`selectCompareBranch` was hard to understand.
Also, it was being needlessly pessimistic with the `ProduceNonFlagSettingCondBr`
case. It assumed that everything in `selectCompareBranch` would emit a TB(N)Z
or C(B)NZ. That's not true; the G_FCMP + G_BRCOND case would never emit those
instructions, and the G_ICMP + G_BRCOND case was capable of emitting an integer
compare + Bcc.
- Refactor `selectCompareBranch` into separate functions based off of what is
feeding the G_BRCOND's condition.
- Move G_BRCOND selection code from `select` to `selectCompareBranch`.
- Remove duplicated constraint code from the code originally in `select`;
`emitTestBit` already handles that, so no need to constrain twice.
- Factor out the G_FCMP + G_BRCOND case into `selectCompareBranchFedByFCmp`.
- Split the G_ICMP + G_BRCOND case into an optimization function,
`tryOptCompareBranchFedByICmp` and a general selection function,
`selectCompareBranchFedByICmp`.
- Reduce the number of things passed to `tryOptAndIntoCompareBranch`.
- Improve documentation.
- Give some variables more descriptive names.
Other than improving the code generation for functions with
speculative_load_hardening by getting the logic correct, this is NFC.
Differential Revision: https://reviews.llvm.org/D92582
I'm not sure if it would be legal by the IR reference to introduce
an addrspacecast here, since the IR reference is a bit vague on
the exact semantics, but at least for our usage of it (and I
suspect for many other's usage) it is not. For us, addrspacecasts
between non-integral address spaces carry frontend information that the
optimizer cannot deduce afterwards in a generic way (though we
have frontend specific passes in our pipline that do propagate
these). In any case, I'm sure nobody is using it this way at
the moment, since it would have introduced inttoptrs, which
are definitely illegal.
Fixes PR38375
Co-authored-by: Keno Fischer <keno@alumni.harvard.edu>
Reviewed By: reames
Differential Revision: https://reviews.llvm.org/D50010
Our internal build bot hit a failure in llvm/test/tools/llvm-symbolizer/pdb/missing_pdb.test
because the test was checking for an error message that is emitted when a pdb file is
missing. But when the drive is mapped to a removalable drive (such as a DVD drive) in
Windows, you get a different error message which causes the test to fail.
This fixes the test by changing the drive the missing pdb is expected to be on to C:\
instead of D:\ as that is the drive historically used to install Windows and thus
if present should be a hard drive.
Reviewed By: rnk
Differential Revision: https://reviews.llvm.org/D92787
When we have a 128-bit register, emitTestBit would incorrectly narrow to 32
bits always. If the bit number was > 32, then we would need a TB(N)ZX. This
would cause a crash, as we'd have the wrong register class. (PR48379)
This generalizes `narrowExtReg` into `moveScalarRegClass`.
This also allows us to remove `widenGPRBankRegIfNeeded` entirely, since
`selectCopy` correctly handles SUBREG_TO_REG etc.
This does create some codegen changes (since `selectCopy` uses the `all`
regclass variants). However, I think that these will likely be optimized away,
and we can always improve the `selectCopy` code. It looks like we should
revisit `selectCopy` at this point, and possibly refactor it into at least one
`emit` function.
Differential Revision: https://reviews.llvm.org/D92707
Build on the work started in 8f07629, and add the multiply case. In the process, more clearly describe the requirement for the operation we're looking through.
Differential Revision: https://reviews.llvm.org/D92726
This stack of changes introduces `llvm-profgen` utility which generates a profile data file from given perf script data files for sample-based PGO. It’s part of(not only) the CSSPGO work. Specifically to support context-sensitive with/without pseudo probe profile, it implements a series of functionalities including perf trace parsing, instruction symbolization, LBR stack/call frame stack unwinding, pseudo probe decoding, etc. Also high throughput is achieved by multiple levels of sample aggregation and compatible format with one stop is generated at the end. Please refer to: https://groups.google.com/g/llvm-dev/c/1p1rdYbL93s for the CSSPGO RFC.
This change supports context-sensitive profile data generation into llvm-profgen. With simultaneous sampling for LBR and call stack, we can identify leaf of LBR sample with calling context from stack sample . During the process of deriving fall through path from LBR entries, we unwind LBR by replaying all the calls and returns (including implicit calls/returns due to inlining) backwards on top of the sampled call stack. Then the state of call stack as we unwind through LBR always represents the calling context of current fall through path.
we have two types of virtual unwinding 1) LBR unwinding and 2) linear range unwinding.
Specifically, for each LBR entry which can be classified into call, return, regular branch, LBR unwinding will replay the operation by pushing, popping or switching leaf frame towards the call stack and since the initial call stack is most recently sampled, the replay should be in anti-execution order, i.e. for the regular case, pop the call stack when LBR is call, push frame on call stack when LBR is return. After each LBR processed, it also needs to align with the next LBR by going through instructions from previous LBR's target to current LBR's source, which we named linear unwinding. As instruction from linear range can come from different function by inlining, linear unwinding will do the range splitting and record counters through the range with same inline context.
With each fall through path from LBR unwinding, we aggregate each sample into counters by the calling context and eventually generate full context sensitive profile (without relying on inlining) to driver compiler's PGO/FDO.
A breakdown of noteworthy changes:
- Added `HybridSample` class as the abstraction perf sample including LBR stack and call stack
* Extended `PerfReader` to implement auto-detect whether input perf script output contains CS profile, then do the parsing. Multiple `HybridSample` are extracted
* Speed up by aggregating `HybridSample` into `AggregatedSamples`
* Added VirtualUnwinder that consumes aggregated `HybridSample` and implements unwinding of calls, returns, and linear path that contains implicit call/return from inlining. Ranges and branches counters are aggregated by the calling context. Here calling context is string type, each context is a pair of function name and callsite location info, the whole context is like `main:1 @ foo:2 @ bar`.
* Added PorfileGenerater that accumulates counters by ranges unfolding or branch target mapping, then generates context-sensitive function profile including function body, inferring callee's head sample, callsite target samples, eventually records into ProfileMap.
* Leveraged LLVM build-in(`SampleProfWriter`) writer to support different serialization format with no stop
- `getCanonicalFnName` for callee name and name from ELF section
- Added regression test for both unwinding and profile generation
Test Plan:
ninja & ninja check-llvm
Reviewed By: hoy, wenlei, wmi
Differential Revision: https://reviews.llvm.org/D89723
Introduce a function that creates a statically-scheduled workshare loop
out of a canonical loop created earlier by the OpenMPIRBuilder. This
basically amounts to injecting runtime calls to the preheader and the
after block and updating the trip count. Static scheduling kind is
currently hardcoded and needs to be extracted from the runtime library
into common TableGen definitions.
Differential Revision: https://reviews.llvm.org/D92476
Added a trivial destructor in release mode and in debug mode a destructor that asserts RefCount is indeed zero.
This ensure people aren't manually (maybe accidentally) destroying these objects like in this contrived example.
```lang=c++
{
std::unique_ptr<SomethingRefCounted> Object;
holdIntrusiveOwnership(Object.get());
// Object Destructor called here will assert.
}
```
Reviewed By: dblaikie
Differential Revision: https://reviews.llvm.org/D92480
Allow sections to be placed into COMDAT groups, in addtion to functions and data
segments.
Also make section symbols unnamed, which allows sections with identical names
(section names are independent of their section symbols, but previously we
gave the symbols the same name as their sections, which results in collisions
when sections are identically-named).
Differential Revision: https://reviews.llvm.org/D92691
This patch adds the ConstraintElimination pass to the LTO pipeline and
also runs it after SCCP in the function simplification pipeline.
This increases the number of cases we can elimination. Pending further
tuning.
The xxeval instruction was intorduced in Power PC in Power 10.
The instruction accepts three vector registers and an immediate.
Depending on the value of the immediate the instruction can be used
to perform certain bitwise boolean operations (and, or, xor, ...) on
the given vector registers.
This patch implements the AND and NAND patterns that can be used by
the instruction.
Reviewed By: nemanjai, #powerpc, bsaleil, NeHuang, jsji
Differential Revision: https://reviews.llvm.org/D92420
A rotate by half the bitwidth swaps the bottom and top half which is the same as one of the MSB GREVI stage.
We have to do this as a special combine because we prefer to keep (rotl/rotr X, BitWidth/2) as a rotate rather than a single stage GREVI.
Differential Revision: https://reviews.llvm.org/D92286
It is possible to merge reuse and reorder shuffles and reduce the total
cost of the ivectorization tree/number of final instructions.
Differential Revision: https://reviews.llvm.org/D92668
This adds code to revert low overhead loops with calls in them before
register allocation. Ideally we would not create low overhead loops with
calls in them to begin with, but that can be difficult to always get
correct. If we want to try and glue together t2LoopDec and t2LoopEnd
into a single instruction, we need to ensure that no instructions use LR
in the loop. (Technically the final code can be better too, as it
doesn't need to use the same registers but that has not been optimized
for here, as reverting loops with calls is expected to be very rare).
It also adds a MVETailPredUtils.h header to share the revert code
between different passes, and provides a place to expand upon, with
RevertLoopWithCall becoming a place to perform other low overhead loop
alterations like removing copies or combining LoopDec and End into a
single instruction.
Differential Revision: https://reviews.llvm.org/D91273
