fma reassoc A, B, C --> fadd (fmul A, B), C (when target has no FMA hardware)
C/C++ code may use explicit fma() calls (which become LLVM fma
intrinsics in IR) but then gets compiled with -ffast-math or similar.
For targets that do not have FMA hardware, we don't want to go out to
the math library for a precise but slow FMA result.
I tried this as a generic DAGCombine, but it caused infinite looping
on more than 1 other target, so there's likely some over-reaching fma
formation happening.
There's also a potential intersection of strict FP with fast-math here.
Deferring to current behavior for that case (assuming that strict-ness
overrides fast-ness).
Differential Revision: https://reviews.llvm.org/D83981
This reverts commit 4500db8c59,
which was reverted because lower thresholds exposed a new issue (PR46680).
Now that it was resolved by d12ec0f752,
we can reinstate lower limits and wait for a new bugreport before
reverting this again...
Both users of predicteinfo (NewGVN and SCCP) are interested in
getting a cmp constraint on the predicated value. They currently
implement separate logic for this. This patch adds a common method
for this in PredicateBase.
This enables a missing bit of PredicateInfo handling in SCCP: Now
the predicate on the condition itself is also used. For switches
it means we know that the switched-on value is the same as the case
value. For assumes/branches we know that the condition is true or
false.
Differential Revision: https://reviews.llvm.org/D83640
This is a step towards trying to remove unnecessary FP compares
with infinity when compiling with -ffinite-math-only or similar.
I'm intentionally not checking FMF on the fcmp itself because
I'm assuming that will go away eventually.
The analysis part of this was added with rGcd481136 for use with
isKnownNeverNaN. Similarly, that could be an enhancement here to
get predicates like 'one' and 'ueq'.
Differential Revision: https://reviews.llvm.org/D84035
Fixes https://bugs.llvm.org/show_bug.cgi?id=46680.
Just like insertions through IRBuilder, InsertNewInstBefore()
should be using the deferred worklist mechanism, so that processing
of newly added instructions is prioritized.
There's one side-effect of the worklist order change which could be
classified as a regression. An add op gets pushed through a select
that at the time is not a umax. We could add a reverse transform
that tries to push adds in the reverse direction to restore a min/max,
but that seems like a sure way of getting infinite loops... Seems
like something that should best wait on min/max intrinsics.
Differential Revision: https://reviews.llvm.org/D84109
As far as I can tell, it should not be necessary for VCTP to be
unpredictable in tail predicated loops. Either it has a a valid loop
counter as a operand which will naturally keep it in the right loop, or
it doesn't and it won't be converted to a tail predicated loop. Not
marking it as having side effects allows it to be scheduled more cleanly
for cases where it is not expected to become a tail predicate loop.
Differential Revision: https://reviews.llvm.org/D83907
.gcno, .gcda and source files can be modified while we are reading them. If the
concurrent modification of a file being read nullifies the NUL terminator
assumption, llvm-cov can trip over an assertion failure in MemoryBuffer::init.
This is not so rare - the source files can be in an editor and .gcda can be
written by an running process (if the process forks, when .gcda gets written is
probably more unpredictable).
There is no accompanying test because an assertion failure requires data
races with some involved setting.
Summary:
In the `ppc-early-ret` pass, we have use `BuildMI` and `copyImplicitOps` when the branch instructions can do the early return. But the two functions will add implicit operands twice, this is not correct.
This patch is to remove the redundant implicit operands in `ppc-early-ret pass`.
Reviewed By: jsji
Differential Revision: https://reviews.llvm.org/D76042
A pass declares itself unskippable by defining a method `static bool isRequired()`.
Also, this patch makes pass managers and adaptor passes required (unskippable).
PassInstrumentation before-pass-callbacks could be used to skip passes by returning false.
However, some passes should not be skipped at all. Especially so for special-purpose passes such as pass managers and adaptor passes since if they are skipped for any reason, the passes contained by them would also be skipped ignoring contained passes's return value of `isRequired()`.
Reviewed By: aeubanks
Differential Revision: https://reviews.llvm.org/D82344
Currently, when parsing text pipeline, different kinds of passes always
introduce nested pass managers. This makes it impossible to test the
adaptor-wrapped user passes from the text pipeline interface which is needed
by D82344 test cases. This also seems useful in general. See comments above
`parsePassPipeline`.
The syntax would be like mixing passes of different types, but it is
not the same as inferring the correct pass type and then adding the
matching nested pass managers. Strictly speaking, the resulted pipelines
are different.
Reviewed By: asbirlea, aeubanks
Differential Revision: https://reviews.llvm.org/D82698
To match GCC (either crossing or not), which doesn't prepend target triple prefixes to `exec_prefixes`.
As an example, powerpc64le-linux-gnu-gcc does not search "powerpc64le-linux-gnu-${name}" in a -B path.
GCC r187297 (2012-05) introduced `__gcov_dump` and `__gcov_reset`.
`__gcov_flush = __gcov_dump + __gcov_reset`
The resolution to https://gcc.gnu.org/PR93623 ("No need to dump gcdas when forking" target GCC 11.0) removed the unuseful and undocumented __gcov_flush.
Close PR38064.
Reviewed By: calixte, serge-sans-paille
Differential Revision: https://reviews.llvm.org/D83149
Currently a capture-default which is not the first element in the lambda-capture
is diagnosed with a generic expected variable name or 'this' in lambda capture
list, which is true but not very helpful.
If we don't have already parsed a capture-default then a lone "&" or "=" is
likely to be a misplaced capture-default, so diagnose it as such.
Differential Revision: https://reviews.llvm.org/D83681
Reviewed By: aaron.ballman
Add a missing newline to IEEE FP flag formatting, and
don't neglect to emit STOP when there's no code number.
Reviewed By: tskeith
Differential Revision: https://reviews.llvm.org/D84060
Summary: For Lw output editing, emit (w-1) blanks before the T or the F.
Reviewed By: sscalpone, PeteSteinfeld
Differential Revision: https://reviews.llvm.org/D84059
Summary:
This patch adds more function attribute information to the runtime function definitions in OMPKinds.def. The goal is to provide sufficient information about OpenMP runtime functions to perform more optimizations on OpenMP code.
Reviewers: jdoerfert
Subscribers: aaron.ballman cfe-commits yaxunl guansong sstefan1 llvm-commits
Tags: #OpenMP #clang #LLVM
Differential Revision: https://reviews.llvm.org/D81031
clang/docs/tools/dump_format_style.py is used to read the comments
from clang/include/clang/Format/Format.h and update the contents of
clang/docs/ClangFormatStyleOptions.rst
Recent changes made these out of date. This commit syncs them by
folding the improved wording back to the comments and then
regenerating the rst file.
Differential Revision: https://reviews.llvm.org/D84103
Each concrete instance of a predicate has a condition (also noted in the
original PredicateBase comment) and to me it seems like there is no
clear benefit of having both PredicateBase and PredicateWithCondition
and they can be folded together.
Reviewers: nikic, efriedma
Reviewed By: nikic
Differential Revision: https://reviews.llvm.org/D84089
Yes, if operands are non-positive this comes at the extra cost
of two extra negations. But a. division is already just
ridiculously costly, two more subtractions can't hurt much :)
and b. we have better/more analyzes/folds for an unsigned division,
we could end up narrowing it's bitwidth, converting it to lshr, etc.
This is essentially a take two on 0fdcca07ad,
which didn't fix the potential regression i was seeing,
because ValueTracking's computeKnownBits() doesn't make use
of dominating conditions in it's analysis.
While i could teach it that, this seems like the more general fix.
This big hammer actually does catch said potential regression.
Over vanilla test-suite + RawSpeed + darktable
(10M IR instrs, 1M IR BB, 1M X86 ASM instrs), this fires/converts 5 more
(+2%) SDiv's, the total instruction count at the end of middle-end pipeline
is only +6, so out of +10 extra negations, ~half are folded away,
and asm instr count is only +1, so practically speaking all extra
negations are folded away and are therefore free.
Sadly, all these new UDiv's remained, none folded away.
But there are two less basic blocks.
https://rise4fun.com/Alive/VS6
Name: v0
Pre: C0 >= 0 && C1 >= 0
%r = sdiv i8 C0, C1
=>
%r = udiv i8 C0, C1
Name: v1
Pre: C0 <= 0 && C1 >= 0
%r = sdiv i8 C0, C1
=>
%t0 = udiv i8 -C0, C1
%r = sub i8 0, %t0
Name: v2
Pre: C0 >= 0 && C1 <= 0
%r = sdiv i8 C0, C1
=>
%t0 = udiv i8 C0, -C1
%r = sub i8 0, %t0
Name: v3
Pre: C0 <= 0 && C1 <= 0
%r = sdiv i8 C0, C1
=>
%r = udiv i8 -C0, -C1
Currently that fold requires both operands to be non-negative,
but the only real requirement for the fold is that we must know
the domains of the operands.
This suppresses `failed to compute relocation: R_PPC_REL32, Invalid data was encountered while parsing the file`
and its 64-bit variants when running llvm-dwarfdump on a PowerPC object file with .eh_frame
Unfortunately it is difficult to test the computation:
DWARFDataExtractor::getEncodedPointer does not use the relocated value
and even if it does, we need to teach llvm-dwarfdump --eh-frame to do
some linker job to report a reasonable address.
Aaron Ballman