As discussed on D96413, as long as the promoted bits of the args are zero we can use the basic ISD::USUBSAT pattern directly, without the shifting like we do for other ops.
I think something similar should be possible for ISD::UADDSAT as well, which I'll look at later.
Also, create a ISD::USUBSAT node directly - this will be expanded back by the legalizer later on if necessary.
Differential Revision: https://reviews.llvm.org/D96622
Instcombine will convert the nonnull and alignment assumption that use the boolean condtion
to an assumption that uses the operand bundles when knowledge retention is enabled.
Differential Revision: https://reviews.llvm.org/D82703
We lost this in D56387/rG69bc0990a9181e6eb86228276d2f59435a7fae67 - where I got the src/dst bitwidths mixed up and assumed getValidShiftAmountConstant would catch it.
Patch by @craig.topper - confirmed by @Carrot that it fixes PR49162
Previously we assumed `rethrow`'s argument was always 0, but it turned
out `rethrow` follows the same rule with `br` or `delegate`:
https://github.com/WebAssembly/exception-handling/pull/137https://github.com/WebAssembly/exception-handling/issues/146#issuecomment-777349038
Currently `rethrow`s generated by our backend always rethrow the
exception caught by the innermost enclosing catch, so this adds a
function to compute that and replaces `rethrow`'s argument with its
computed result.
This also renames `EHPadStack` in `InstPrinter` to `TryStack`, because
in CFGStackify we use `EHPadStack` to mean the range between
`catch`~`end`, while in `InstPrinter` we used it to mean the range
between `try`~`catch`, so choosing different names would look clearer.
Doesn't contain any functional changes in `InstPrinter`.
Reviewed By: dschuff
Differential Revision: https://reviews.llvm.org/D96595
Perform DSOLocal propagation within summary list of every GV. This
avoids the repeated query of this information during function
importing.
Differential Revision: https://reviews.llvm.org/D96398
In the past, it was stated in D87994 that it is allowed to dereference a pointer that is partially undefined
if all of its possible representations fit into a dereferenceable range.
The motivation of the direction was to make a range analysis helpful for assuring dereferenceability.
Even if a range analysis concludes that its offset is within bounds, the offset could still be partially undefined; to utilize the range analysis, this relaxation was necessary.
https://groups.google.com/g/llvm-dev/c/2Qk4fOHUoAE/m/KcvYMEgOAgAJ has more context about this.
However, this is currently blocking another optimization, which is annotating the noundef attribute for library functions' arguments. D95122 is the patch.
Currently, there are quite a few library functions which cannot have noundef attached to its pointer argument because it can be transformed from load/store.
For example, MemCpyOpt can convert stores into memset:
```
store p, i32 0
store (p+1), i32 0 // Since currently it is allowed for store to have partially undefined pointer..
->
memset(p, 0, 8) // memset cannot guarantee that its ptr argument is noundef.
```
A bigger problem is that this makes unclear which library functions are allowed to have 'noundef' and which functions aren't (e.g., strlen).
This makes annotating noundef almost impossible for this kind of functions.
This patch proposes that all memory operations should have well-defined pointers.
For memset/memcpy, it is semantically equivalent to running a loop until the size is met (and branching on undef is UB), so the size is also updated to be well-defined.
Strictly speaking, this again violates the implication of dereferenceability from range analysis result.
However, I think this is okay for the following reasons:
1. It seems the existing analyses in the LLVM main repo does not have conflicting implementation with the new proposal.
`isDereferenceableAndAlignedPointer` works only when the GEP offset is constant, and `isDereferenceableAndAlignedInLoop` is also fine.
2. A possible miscompilation happens only when the source has a pointer with a *partially* undefined offset (it's okay with poison because there is no 'partially poison' value).
But, at least I'm not aware of a language using LLVM as backend that has a well-defined program while allowing partially undefined pointers.
There might be such a language that I'm not aware of, but improving the performance of the mainstream languages like C and Rust is more important IMHO.
Reviewed By: jdoerfert
Differential Revision: https://reviews.llvm.org/D95238
As of binutils 2.36, GNU strip calls chown(2) for "sudo strip foo" and
"sudo strip foo -o foo", but no "sudo strip foo -o bar" or "sudo strip
foo -o ./foo". In other words, while "sudo strip foo -o bar" creates a
new file bar with root access, "sudo strip foo" will keep the owner and
group of foo unchanged. Currently llvm-objcopy and llvm-strip behave
differently, always changing the owner and gropu to root. The
discrepancy prevents Chrome OS from migrating to llvm-objcopy and
llvm-strip as they change file ownership and cause intended users/groups
to lose access when invoked by sudo with the following sequence
(recommended in man page of GNU strip).
1.<Link the executable as normal.>
1.<Copy "foo" to "foo.full">
1.<Run "strip --strip-debug foo">
1.<Run "objcopy --add-gnu-debuglink=foo.full foo">
This patch makes llvm-objcopy and llvm-strip follow GNU's behavior.
Link: crbug.com/1108880
This patch hides the logic for setting the location kind of an entry
value inside the begin/finalize/cancel functions. This way we get rid
the strange workaround that is currently in setLocation().
In the future, this will allow us to set the location kind of the
entry value independently from the location kind of the main
expression.
Differential Revision: https://reviews.llvm.org/D96554
It appears some instructions doesn't have the debug location info and the symbolizer will return an empty call stack for them which will cause some crash later in profile unwinding. Actually we do not record the sample info for them, so this change just filter out those instruction.
As those instruction would appears at the begin and end of the instruction list, without them we need to add the boundary check for IP `advance` and `backward`.
Also for pseudo probe based profile, we actually don't need the symbolized location info, so here just change to use an empty stack for it. This could save half of the binary loading time.
Differential Revision: https://reviews.llvm.org/D96434
I've already witnessed two separate changes missing runNewPMPasses()
because runNewPMCustomPasses() is so similar.
This cleans up some duplicated code.
Reviewed By: tejohnson
Differential Revision: https://reviews.llvm.org/D96553
This include some changes related with PerfReader's the input check and command line change:
1) It appears there might be thousands of leading MMAP-Event line in the perfscript for large workload. For this case, the 4k threshold is not eligible to determine it's a hybrid sample. This change renovated the `isHybridPerfScript` by going through the script without threshold limitation checking whether there is a non-empty call stack immediately followed by a LBR sample. It will stop once it find a valid one.
2) Added several input validations for the command line switches in PerfReader.
3) Changed the command line `show-disassembly` to `show-disassembly-only`, it will print to stdout and exit early which leave an empty output profile.
Reviewed By: hoy, wenlei
Differential Revision: https://reviews.llvm.org/D96387
This is pretty much just ports `performGlobalAddressCombine` from
AArch64ISelLowering. (AArch64 doesn't use the generic DAG combine for this.)
This adds a pre-legalize combine which looks for this pattern:
```
%g = G_GLOBAL_VALUE @x
%ptr1 = G_PTR_ADD %g, cst1
%ptr2 = G_PTR_ADD %g, cst2
...
%ptrN = G_PTR_ADD %g, cstN
```
And then, if possible, transforms it like so:
```
%g = G_GLOBAL_VALUE @x
%offset_g = G_PTR_ADD %g, -min(cst)
%ptr1 = G_PTR_ADD %offset_g, cst1
%ptr2 = G_PTR_ADD %offset_g, cst2
...
%ptrN = G_PTR_ADD %offset_g, cstN
```
Where min(cst) is the smallest out of the G_PTR_ADD constants.
This means we should save at least one G_PTR_ADD.
This also updates code in the legalizer + selector which assumes that
G_GLOBAL_VALUE will never have an offset and adds/updates relevant tests.
Differential Revision: https://reviews.llvm.org/D96624
There's no need to call verifyVectorElementMatch since we already know
that the source and destination types are identical.
Differential Revision: https://reviews.llvm.org/D96589
Rather than storing the query depth in AAResults, store it in AAQI.
This makes more sense, as it is a property of the query. This
sidesteps the issue of D94363, fixing slightly inaccurate AA
statistics. Additionally, I plan to use the Depth from BasicAA in
the future, where fetching it from AAResults would be unreliable.
This change is not quite as straightforward as it seems, because
we need to preserve the depth when creating a new AAQI for recursive
queries across phis. I'm adding a new method for this, as we may
need to preserve additional information here in the future.
This combine tries to do inter-block hoisting of extends of G_PHIs, into the
originating blocks of the phi's incoming value. The idea is to expose further
optimization opportunities that are normally obscured by the PHI.
Some basic heuristics, and a target hook for AArch64 is added, to allow tuning.
E.g. if the extend is used by a G_PTR_ADD, it doesn't perform this combine
since it may be folded into the addressing mode during selection.
There are very minor code size improvements on AArch64 -Os, but the real benefit
is that it unlocks optimizations like AArch64 conditional compares on some
benchmarks.
Differential Revision: https://reviews.llvm.org/D95703
Their names don't convey much information, so they should be excluded.
The behavior matches addr2line.
Differential Revision: https://reviews.llvm.org/D96617
Some of these accidentally disabled tests failed as a result; updated
tests per @qcolombet instructions. A small number needed additional
updates because legalization has actually changed since they were
written.
Found by the Rotten Green Tests project.
Differential Revision: https://reviews.llvm.org/D95257
Given a floating point store from an extracted vector, with an integer
VGETLANE that already exists, storing the existing VGETLANEu directly
can be better for performance. As the value is known to already be in an
integer registers, this can help reduce fp register pressure, removed
the need for the fp extract and allows use of more integer post-inc
stores not available with vstr.
This can be a bit narrow in scope, but helps with certain biquad kernels
that store shuffled vector elements.
Differential Revision: https://reviews.llvm.org/D96159
This patch intended to provide additional interface to LLVMsymbolizer
such that they work directly on object files. There is an existing
method - symbolizecode which takes an object file, this patch provides
similar overloads for symbolizeInlinedCode, symbolizeData,
symbolizeFrame. This can be useful for clients who already have a
in-memory object files to symbolize for.
Patch By: pvellien (praveen velliengiri)
Reviewed By: scott.linder
Differential Revision: https://reviews.llvm.org/D95232
Begin transitioning the X86 vector code to recognise sub(umax(a,b) ,b) or sub(a,umin(a,b)) USUBSAT patterns to make it more generic and available to all targets.
This initial patch just moves the basic umin/umax patterns to DAG, removing some vector-only checks on the way - these are some of the patterns that the legalizer will try to expand back to so we can be reasonably relaxed about matching these pre-legalization.
We can handle the trunc(sub(..))) variants as well, which helps with patterns where we were promoting to a wider type to detect overflow/saturation.
The remaining x86 code requires some cleanup first - some of it isn't actually tested etc. I also need to resurrect D25987.
Differential Revision: https://reviews.llvm.org/D96413
This allows for suspend point specific resume function types.
Return values from a suspend point can therefore be modelled as
arguments to the resume function. Allowing for directly passed return
types.
Differential Revision: https://reviews.llvm.org/D96136
These two instructions are VOP3P and have op_sel_hi bits,
however do not use op_sel_hi. That is recommended to set
unused op_sel_hi bits to 1. However, we cannot decode
both representations with 1 and 0 if bits are set to
default value 1. If bits are set to be ignored with '?'
initializer then encoding defaults them to 0.
The patch is a hack to force ignored '?' bits to 1 on
encoding for these instructions.
There is still canonicalization happens on disasm print
if incoming values are non-default, so that disasm output
does not match binary input, but this is pre-existing
problem for all instructions with '?' bits.
Fixes: SWDEV-272540
Differential Revision: https://reviews.llvm.org/D96543
This patch adds a pass to replace calls to vector intrinsics (i.e., LLVM
intrinsics operating on vector operands) with calls to a vector library.
Currently, calls to LLVM intrinsics are only replaced with calls to vector
libraries when scalar calls to intrinsics are vectorized by the Loop- or
SLP-Vectorizer.
With this pass, it is now possible to replace calls to LLVM intrinsics
already operating on vector operands, e.g., if such code was generated
by MLIR. For the replacement, information from the TargetLibraryInfo,
e.g., as specified via -vector-library is used.
This is a re-try of the original commit 2303e93e66 that was reverted
due to pass manager problems. Other minor changes have also been made.
Differential Revision: https://reviews.llvm.org/D95373
explicitly emitting retainRV or claimRV calls in the IR
Background:
This fixes a longstanding problem where llvm breaks ARC's autorelease
optimization (see the link below) by separating calls from the marker
instructions or retainRV/claimRV calls. The backend changes are in
https://reviews.llvm.org/D92569.
https://clang.llvm.org/docs/AutomaticReferenceCounting.html#arc-runtime-objc-autoreleasereturnvalue
What this patch does to fix the problem:
- The front-end adds operand bundle "clang.arc.attachedcall" to calls,
which indicates the call is implicitly followed by a marker
instruction and an implicit retainRV/claimRV call that consumes the
call result. In addition, it emits a call to
@llvm.objc.clang.arc.noop.use, which consumes the call result, to
prevent the middle-end passes from changing the return type of the
called function. This is currently done only when the target is arm64
and the optimization level is higher than -O0.
- ARC optimizer temporarily emits retainRV/claimRV calls after the calls
with the operand bundle in the IR and removes the inserted calls after
processing the function.
- ARC contract pass emits retainRV/claimRV calls after the call with the
operand bundle. It doesn't remove the operand bundle on the call since
the backend needs it to emit the marker instruction. The retainRV and
claimRV calls are emitted late in the pipeline to prevent optimization
passes from transforming the IR in a way that makes it harder for the
ARC middle-end passes to figure out the def-use relationship between
the call and the retainRV/claimRV calls (which is the cause of
PR31925).
- The function inliner removes an autoreleaseRV call in the callee if
nothing in the callee prevents it from being paired up with the
retainRV/claimRV call in the caller. It then inserts a release call if
claimRV is attached to the call since autoreleaseRV+claimRV is
equivalent to a release. If it cannot find an autoreleaseRV call, it
tries to transfer the operand bundle to a function call in the callee.
This is important since the ARC optimizer can remove the autoreleaseRV
returning the callee result, which makes it impossible to pair it up
with the retainRV/claimRV call in the caller. If that fails, it simply
emits a retain call in the IR if retainRV is attached to the call and
does nothing if claimRV is attached to it.
- SCCP refrains from replacing the return value of a call with a
constant value if the call has the operand bundle. This ensures the
call always has at least one user (the call to
@llvm.objc.clang.arc.noop.use).
- This patch also fixes a bug in replaceUsesOfNonProtoConstant where
multiple operand bundles of the same kind were being added to a call.
Future work:
- Use the operand bundle on x86-64.
- Fix the auto upgrader to convert call+retainRV/claimRV pairs into
calls with the operand bundles.
rdar://71443534
Differential Revision: https://reviews.llvm.org/D92808
