This silences the warning below:

llvm-project/llvm/lib/Analysis/DomTreeUpdater.cpp:510:20: warning: loop variable 'BB' is always a copy because the range of type 'const SmallPtrSet<llvm::BasicBlock *, 8>' does not return a reference [-Wrange-loop-analysis]
  for (const auto &BB : DeletedBBs) {
                   ^
llvm-project/llvm/lib/Analysis/DomTreeUpdater.cpp:510:8: note: use non-reference type 'llvm::BasicBlock *'
  for (const auto &BB : DeletedBBs) {
       ^~~~~~~~~~~~~~~~
1 warning generated.

In the attached test case, a non-terminator instruction (DBG_VALUE) is
inserted after a terminator, producing an invalid MBB.

TransposeOp are often followed by ExtractOp.
In certain cases however, it is unnecessary (and even detrimental) to lower a TransposeOp to either a flat transpose (llvm.matrix intrinsics) or to unrolled scalar insert / extract chains.

Providing foldings of ExtractOp mitigates some of the unnecessary complexity.

Differential revision: https://reviews.llvm.org/D83487

This makes the input dump filtering implemented by D82203 more
configurable.  D82203 enables filtering out everything but the initial
input lines of error diagnostics (plus some context).  This patch
enables including any line with any kind of annotation.

Reviewed By: mehdi_amini

Differential Revision: https://reviews.llvm.org/D83097

For example, given `-dump-input-context=3 -vv`, the following now
shows more leading context for the error than requested because a
leading ellipsis would occupy the same number of lines as it would
elide:

```
<<<<<<
         1: foo6
         2: foo5
         3: foo4
         4: foo3
         5: foo2
         6: foo1
         7: hello world
check:1     ^~~~~
check:2           X~~~~ error: no match found
         8: foo1
check:2     ~~~~
         9: foo2
check:2     ~~~~
        10: foo3
check:2     ~~~~
         .
         .
         .
>>>>>>
```

Reviewed By: mehdi_amini

Differential Revision: https://reviews.llvm.org/D83526

This patch is motivated by discussions at each of:

* <https://reviews.llvm.org/D81422>
* <http://lists.llvm.org/pipermail/llvm-dev/2020-June/142369.html>

When input is dumped as specified by `-dump-input=fail`, this patch
filters the dump to show only input lines that are the starting lines
of error diagnostics plus the number of contextual lines specified
`-dump-input-context` (defaults to 5).

When `-dump-input=always`, there might be not be any errors, so all
input lines are printed, as without this patch.

Here's some sample output with `-dump-input-context=3 -vv`:

```
<<<<<<
           .
           .
           .
          13: foo
          14: foo
          15: hello world
check:1       ^~~~~~~~~~~
          16: foo
check:2'0     X~~ error: no match found
          17: foo
check:2'0     ~~~
          18: foo
check:2'0     ~~~
          19: foo
check:2'0     ~~~
           .
           .
           .
          27: foo
check:2'0     ~~~
          28: foo
check:2'0     ~~~
          29: foo
check:2'0     ~~~
          30: goodbye word
check:2'0     ~~~~~~~~~~~~
check:2'1     ?            possible intended match
          31: foo
check:2'0     ~~~
          32: foo
check:2'0     ~~~
          33: foo
check:2'0     ~~~
           .
           .
           .
>>>>>>
```

Reviewed By: mehdi_amini, arsenm, jhenderson, rsmith, SjoerdMeijer, Meinersbur, lattner

Differential Revision: https://reviews.llvm.org/D82203

When building in Debug on Windows-MSVC after b7402edc, a lot of tests were failing because we were dereferencing an element past the end of HashRecords. This happened towards the end of the table, in unused slots.

Summary: Mostly a few methods and message names have been renamed.

Reviewers: hokein

Subscribers: ilya-biryukov, MaskRay, jkorous, arphaman, kadircet, usaxena95, cfe-commits

Tags: #clang

Differential Revision: https://reviews.llvm.org/D83556

This relands commit cd7f8051 that was
reverted since lower threshold have successfully found an issue.
Now that the issue is fixed, let's wait until the next one is reported.

This reverts commit caa423ee.

We can happen to have a situation with many stores eligible for transform,
but due to our visitation order (top to bottom), when we have processed
the first eligible instruction, we would not try to reprocess the previous
instructions that are now also eligible.

So after we've successfully merged a store that was second-to-last instruction
into successor, if the now-second-to-last instruction is also a such store
that is eligible, add it to worklist to be revisited.

Fixes https://bugs.llvm.org/show_bug.cgi?id=46661

The testcase should pass with a single instcombine iteration.

Use the new -fexperimental-strict-floating-point flag in more cases to
fix the arm and aarch64 bots.

Differential Revision: https://reviews.llvm.org/D80952

This revision adds support for vectorizing named and generic contraction ops to vector.contract. Cases in which the memref is 0-D are special cased to emit std.load/std.store instead of vector.transfer. Relevant tests are added.

Differential revision: https://reviews.llvm.org/D83307

Fixes https://github.com/clangd/clangd/issues/455

Differential Revision: https://reviews.llvm.org/D83546

This revision adds folding to ExtractOp by simply concatenating the position attributes.

We currently have strict floating point/constrained floating point enabled
for all targets. Constrained SDAG nodes get converted to the regular ones
before reaching the target layer. In theory this should be fine.

However, the changes are exposed to users through multiple clang options
already in use in the field, and the changes are _completely_ _untested_
on almost all of our targets. Bugs have already been found, like
"https://bugs.llvm.org/show_bug.cgi?id=45274".

This patch disables constrained floating point options in clang everywhere
except X86 and SystemZ. A warning will be printed when this happens.

Use the new -fexperimental-strict-floating-point flag to force allowing
strict floating point on hosts that aren't already marked as supporting
it (X86 and SystemZ).

Differential Revision: https://reviews.llvm.org/D80952

This reverts commit af839a96.

Some issues appear to be being caused by this. Reverting whilst we
investigate.

Reviewers: hokein

Subscribers: ilya-biryukov, MaskRay, jkorous, arphaman, kadircet, usaxena95, cfe-commits

Tags: #clang

Differential Revision: https://reviews.llvm.org/D83511

The PC Relative code allows for calls that are marked with the relocation
R_PPC64_REL24_NOTOC. This indicates that the caller does not have a valid TOC
pointer in R2 and does not require R2 to be restored after the call.

This patch is added to support local calls to callees tha also do not have a TOC.

Reviewed By: sfertile, MaskRay, stefanp

Differential Revision: https://reviews.llvm.org/D82816

Many platform ABIs have special support for passing aggregates that
either just contain a single member of floatint-point type, or else
a homogeneous set of members of the same floating-point type.

When making this determination, any extra "empty" members of the
aggregate type will typically be ignored.  However, in C++ (at least
in all prior versions), no data member would actually count as empty,
even if it's type is an empty record -- it would still be considered
to take up at least one byte of space, and therefore make those ABI
special cases not apply.

This is now changing in C++20, which introduced the [[no_unique_address]]
attribute.  Members of empty record type, if they also carry this
attribute, now do *not* take up any space in the type, and therefore
the ABI special cases for single-element or homogeneous aggregates
should apply.

The C++ Itanium ABI has been updated accordingly, and GCC 10 has
added support for this new case.  This patch now adds support to
LLVM.  This is cross-platform; it affects all platforms that use
the single-element or homogeneous aggregate ABI special case and
implement this using any of the following common subroutines
in lib/CodeGen/TargetInfo.cpp:
  isEmptyField
  isEmptyRecord
  isSingleElementStruct
  isHomogeneousAggregate

Avoids unnecessary copies and silences clang tidy warning.

Avoids unnecessary copies and silences clang tidy warning - we do this in most places, there are just a few that were missed.

Summary:
Since changing the Predicate to be an unsigned enum, the lower bound check for
isFPPredicate no longer needs to check the lower bound, since
it will always evaluate to true.

Also fixed a similar issue in SIISelLowering.cpp by removing the need for
comparing to FIRST and LAST predicates

Added an assert to the isFPPredicate comparison to flag if the
FIRST_FCMP_PREDICATE is ever changed to anything other than 0, in which case the
logic will break.

Without this change warnings are generated in VS.

Change-Id: I358f0daf28c0628c7bda8ad4cab4e1757b761bab

Subscribers: arsenm, jvesely, nhaehnle, hiraditya, kerbowa, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D83540

 Lower fixed length vector truncates to a sequence of SVE UZP1 instructions.

Differential Revision: https://reviews.llvm.org/D83395

Change the code the use the version which accepts a memory buffer,
instead of the one taking a file name.

This ensures we are not loading the file into memory twice
(ObjectFilePECOFF also loads a copy), reducing our memory footprint, as
well as enabling additional goodies in the future, like being able to
open files which don't exist on disk (D83512).

The check assumed the matched function call has 3 arguments, but the
matcher didn't guaranteed that.

Differential Revision: https://reviews.llvm.org/D83301

Currently the DomTree is not kept up to date for additional blocks
generated in the vector loop, for example when vectorizing with
predication. SCEVExpander relies on dominance checks when looking for
existing instructions to re-use and in some cases that can lead to the
expander picking instructions that do not actually dominate their insert
point (e.g. as in PR46525).

Unfortunately keeping the DT up-to-date is a bit tricky, because the CFG
is only patched up after generating code for a block. For now, we can
just use the vector loop header, as this ensures the inserted
instructions dominate all uses in the vector loop. There should be no
noticeable impact on the generated code, as other passes should sink
those instructions, if profitable.

Fixes PR46525.

Reviewers: Ayal, gilr, mkazantsev, dmgreen

Reviewed By: dmgreen

Differential Revision: https://reviews.llvm.org/D83288

Add missing mappings and tablegen definitions for TBUFFER_STORE_FORMAT.

Differential Revision: https://reviews.llvm.org/D83240

Avoids unnecessary APInt copies and silences clang tidy warning.

Truncations lowered as shuffles of multiple (concatenated) vectors often leave us with lane-crossing shuffles that feed a PACKSS/PACKUS, if both shuffles are fed from the same 2 vector sources, then we can PACK the sources directly and shuffle the result instead.

This is currently limited to whole i128 lanes in a 256-bit vector, but we can extend this if the need arises (but I'm not seeing many examples in real world code).

Differential Revision: https://reviews.llvm.org/D83374

Differential Revision: https://reviews.llvm.org/D83373

Differential Revision: https://reviews.llvm.org/D82967

Summary:
While benchmarking uint128 division we found out that it has huge latency for small divisors

https://reviews.llvm.org/D83027

```
Benchmark                                                   Time(ns)        CPU(ns)     Iterations
--------------------------------------------------------------------------------------------------
BM_DivideIntrinsic128UniformDivisor<unsigned __int128>            13.0           13.0     55000000
BM_DivideIntrinsic128UniformDivisor<__int128>                     14.3           14.3     50000000
BM_RemainderIntrinsic128UniformDivisor<unsigned __int128>         13.5           13.5     52000000
BM_RemainderIntrinsic128UniformDivisor<__int128>                  14.1           14.1     50000000
BM_DivideIntrinsic128SmallDivisor<unsigned __int128>             153            153        5000000
BM_DivideIntrinsic128SmallDivisor<__int128>                      170            170        3000000
BM_RemainderIntrinsic128SmallDivisor<unsigned __int128>          153            153        5000000
BM_RemainderIntrinsic128SmallDivisor<__int128>                   155            155        5000000
```

This patch suggests a more optimized version of the division:

If the divisor is 64 bit, we can proceed with the divq instruction on x86 or constant multiplication mechanisms for other platforms. Once both divisor and dividend are not less than 2**64, we use branch free subtract algorithm, it has at most 64 cycles. After that our benchmarks improved significantly

```
Benchmark                                                   Time(ns)        CPU(ns)     Iterations
--------------------------------------------------------------------------------------------------
BM_DivideIntrinsic128UniformDivisor<unsigned __int128>            11.0           11.0     64000000
BM_DivideIntrinsic128UniformDivisor<__int128>                     13.8           13.8     51000000
BM_RemainderIntrinsic128UniformDivisor<unsigned __int128>         11.6           11.6     61000000
BM_RemainderIntrinsic128UniformDivisor<__int128>                  13.7           13.7     52000000
BM_DivideIntrinsic128SmallDivisor<unsigned __int128>              27.1           27.1     26000000
BM_DivideIntrinsic128SmallDivisor<__int128>                       29.4           29.4     24000000
BM_RemainderIntrinsic128SmallDivisor<unsigned __int128>           27.9           27.8     26000000
BM_RemainderIntrinsic128SmallDivisor<__int128>                    29.1           29.1     25000000
```

If not using divq instrinsics, it is still much better

```
Benchmark                                                   Time(ns)        CPU(ns)     Iterations
--------------------------------------------------------------------------------------------------
BM_DivideIntrinsic128UniformDivisor<unsigned __int128>            12.2           12.2     58000000
BM_DivideIntrinsic128UniformDivisor<__int128>                     13.5           13.5     52000000
BM_RemainderIntrinsic128UniformDivisor<unsigned __int128>         12.7           12.7     56000000
BM_RemainderIntrinsic128UniformDivisor<__int128>                  13.7           13.7     51000000
BM_DivideIntrinsic128SmallDivisor<unsigned __int128>              30.2           30.2     24000000
BM_DivideIntrinsic128SmallDivisor<__int128>                       33.2           33.2     22000000
BM_RemainderIntrinsic128SmallDivisor<unsigned __int128>           31.4           31.4     23000000
BM_RemainderIntrinsic128SmallDivisor<__int128>                    33.8           33.8     21000000
```

PowerPC benchmarks:

Was
```
BM_DivideIntrinsic128UniformDivisor<unsigned __int128>            22.3           22.3     32000000
BM_DivideIntrinsic128UniformDivisor<__int128>                     23.8           23.8     30000000
BM_RemainderIntrinsic128UniformDivisor<unsigned __int128>         22.5           22.5     32000000
BM_RemainderIntrinsic128UniformDivisor<__int128>                  24.9           24.9     29000000
BM_DivideIntrinsic128SmallDivisor<unsigned __int128>             394            394        2000000
BM_DivideIntrinsic128SmallDivisor<__int128>                      397            397        2000000
BM_RemainderIntrinsic128SmallDivisor<unsigned __int128>          399            399        2000000
BM_RemainderIntrinsic128SmallDivisor<__int128>                   397            397        2000000
```

With this patch
```
BM_DivideIntrinsic128UniformDivisor<unsigned __int128>            21.7           21.7     33000000
BM_DivideIntrinsic128UniformDivisor<__int128>                     23.0           23.0     31000000
BM_RemainderIntrinsic128UniformDivisor<unsigned __int128>         21.9           21.9     33000000
BM_RemainderIntrinsic128UniformDivisor<__int128>                  23.9           23.9     30000000
BM_DivideIntrinsic128SmallDivisor<unsigned __int128>              32.7           32.6     23000000
BM_DivideIntrinsic128SmallDivisor<__int128>                       33.4           33.4     21000000
BM_RemainderIntrinsic128SmallDivisor<unsigned __int128>           31.1           31.1     22000000
BM_RemainderIntrinsic128SmallDivisor<__int128>                    33.2           33.2     22000000
```

My email: danilak@google.com, I don't have commit rights

Reviewers: howard.hinnant, courbet, MaskRay

Reviewed By: courbet

Subscribers: steven.zhang, #sanitizers

Tags: #sanitizers

Differential Revision: https://reviews.llvm.org/D81809