The previous attempt in d34c8c70 didn't help (the problem was missing
indentation), and another issue was introduced by a51d51a0.

Delete an implied condition (E.NumIn <= CB.NumIn)

Previous description didn't actually state the effect the attribute has on
thread safety analysis (causing analysis to assume the capability is held).

Previous description was also ambiguous about (or slightly overstated) the
noreturn assumption made by thread safety analysis, implying the assumption had
to be true about the function's behavior in general, and not just its behavior
in places where it's used. Stating the assumption specifically should avoid a
perceived need to disable thread safety analysis in places where only asserting
that a specific capability is held would be better.

Reviewed By: aaronpuchert, vasild

Differential Revision: https://reviews.llvm.org/D87629

SAVE statement, according to 8.6.14, must apply to the same scoping
unit, that excludes nested scoping units. For example, if the SAVE
statement is found in a MODULE, the functions contained in that module
should not inherit the SAVE attribute. I think that the code was doing
this, failing the following source:

```
MODULE pippo
SAVE

CONTAINS
PURE FUNCTION fft_stick_index( )
   IMPLICIT NONE
   INTEGER :: fft_stick_index
   INTEGER :: mc  !error: A pure subprogram may not have a variable with the SAVE attribute
END FUNCTION

END MODULE
```

Differential Revision: https://reviews.llvm.org/D88279

There appears to be a mis-compile with MemorySSA-backed DSE in
combination with llvm.lifetime.end. It currently appears like
DSE is doing the right thing and the llvm.lifetime.end markers
are incorrect. The reverted patch uncovers the mis-compile.

This patch temporarily switches back to the legacy DSE
implementation, while we investigate.

This reverts commit 9d172c8e.

Was testing on case insensitive config :-/

Many x86/x64 SSE tests codegen are the same so avoid duplication

If we're multiplying all elements of a vector by '0' or '1' then we can more efficiently perform this as a clearing mask (that is likely to further simplify to a shuffle blend).

This was noticed when reviewing D87502 but seems to help idiv/irem by constant cases even more as '0'/'1' values are often used for 'passthrough' cases.

Differential Revision: https://reviews.llvm.org/D88225

The test `AST/const-fpfeatures-diag.c` requires setting strict FP
semantics, so it fails on targets where support of such semantic
is limited.

When looking for memory defs killed by memory terminators the code
currently incorrectly ignores the size argument of llvm.lifetime.end.

This patch updates the code to use isMemTerminator and updates
isMemTerminator to use isOverwrite() to make sure locations that are
outside the range marked as dead by llvm.lifetime.end are not
considered. Note that isOverwrite is only used for llvm.lifetime.end,
because free-like functions make the whole underlying object dead.

llvm.lifetime.end accepts a size parameters to limit the size of the
location marked as dead. Add a few tests with stores to locations after
the part that has been marked as dead.

The change implements evaluation of constant floating point expressions
under non-default rounding modes. The main objective was to support
evaluation of global variable initializers, where constant rounding mode
may be specified by `#pragma STDC FENV_ROUND`.

Differential Revision: https://reviews.llvm.org/D87822

This pervent very poor optimization caused by a signle assume like https://godbolt.org/z/EK3oMh

baseline flags: -O3
patched flags: -O3 -mllvm --enable-knowledge-retention

Before the patch
```
Metric: compile_time
Program                                                      baseline patched diff
             test-suite :: CTMark/tramp3d-v4/tramp3d-v4.test  20.72    29.74  43.5%
                     test-suite :: CTMark/Bullet/bullet.test  24.39    24.91   2.2%
               test-suite :: CTMark/7zip/7zip-benchmark.test  37.39    38.06   1.8%
                      test-suite :: CTMark/kimwitu++/kc.test  11.76    11.94   1.5%
                   test-suite :: CTMark/sqlite3/sqlite3.test  12.94    12.91  -0.3%
                       test-suite :: CTMark/SPASS/SPASS.test  11.72    11.70  -0.2%
                     test-suite :: CTMark/lencod/lencod.test  16.12    16.10  -0.1%
                   test-suite :: CTMark/ClamAV/clamscan.test  13.31    13.30  -0.1%
              test-suite :: CTMark/mafft/pairlocalalign.test   9.12     9.12  -0.1%
 test-suite :: CTMark/consumer-typeset/consumer-typeset.test   9.34     9.34  -0.1%
                                          Geomean difference                   4.2%

Metric: compiler_Kinst_count
Program                                                      baseline     patched      diff
             test-suite :: CTMark/tramp3d-v4/tramp3d-v4.test 107576069.87 172886418.90 60.7%
                     test-suite :: CTMark/Bullet/bullet.test 123291865.66 125457117.96  1.8%
                      test-suite :: CTMark/kimwitu++/kc.test  56347884.64  57298544.14  1.7%
               test-suite :: CTMark/7zip/7zip-benchmark.test 180637699.58 183341656.57  1.5%
                   test-suite :: CTMark/sqlite3/sqlite3.test  66723788.85  66664692.80 -0.1%
                   test-suite :: CTMark/ClamAV/clamscan.test  69581500.56  69597863.92  0.0%
                     test-suite :: CTMark/lencod/lencod.test  94236501.48  94216545.32 -0.0%
                       test-suite :: CTMark/SPASS/SPASS.test  58516756.95  58505089.07 -0.0%
 test-suite :: CTMark/consumer-typeset/consumer-typeset.test  48832815.53  48841989.39  0.0%
              test-suite :: CTMark/mafft/pairlocalalign.test  49682720.53  49686324.34  0.0%
                                          Geomean difference                            5.4%
```

After the patch
```
Metric: compile_time
Program                                                      baseline patched diff
             test-suite :: CTMark/tramp3d-v4/tramp3d-v4.test  20.70    22.40   8.2%
               test-suite :: CTMark/7zip/7zip-benchmark.test  37.13    38.05   2.5%
                     test-suite :: CTMark/Bullet/bullet.test  24.25    24.83   2.4%
                      test-suite :: CTMark/kimwitu++/kc.test  11.69    11.94   2.2%
                   test-suite :: CTMark/ClamAV/clamscan.test  13.19    13.36   1.3%
                     test-suite :: CTMark/lencod/lencod.test  16.02    16.19   1.1%
 test-suite :: CTMark/consumer-typeset/consumer-typeset.test   9.29     9.36   0.7%
                       test-suite :: CTMark/SPASS/SPASS.test  11.64    11.73   0.7%
              test-suite :: CTMark/mafft/pairlocalalign.test   9.10     9.15   0.5%
                   test-suite :: CTMark/sqlite3/sqlite3.test  12.95    12.96   0.0%
                                          Geomean difference                   1.9%

Metric: compiler_Kinst_count
Program                                                      baseline     patched      diff
             test-suite :: CTMark/tramp3d-v4/tramp3d-v4.test 107590933.61 114044834.72  6.0%
                      test-suite :: CTMark/kimwitu++/kc.test  56344526.77  57235806.29  1.6%
                     test-suite :: CTMark/Bullet/bullet.test 123291285.10 125128334.97  1.5%
               test-suite :: CTMark/7zip/7zip-benchmark.test 180641540.10 183155706.39  1.4%
                   test-suite :: CTMark/sqlite3/sqlite3.test  66725619.22  66668713.92 -0.1%
                       test-suite :: CTMark/SPASS/SPASS.test  58509029.85  58478704.75 -0.1%
 test-suite :: CTMark/consumer-typeset/consumer-typeset.test  48843711.23  48826894.68 -0.0%
                     test-suite :: CTMark/lencod/lencod.test  94233305.79  94207544.23 -0.0%
                   test-suite :: CTMark/ClamAV/clamscan.test  69587887.66  69603549.90  0.0%
              test-suite :: CTMark/mafft/pairlocalalign.test  49686968.65  49689291.04  0.0%
                                          Geomean difference                            1.0%
```

Reviewed By: jdoerfert, efriedma

Differential Revision: https://reviews.llvm.org/D86816

This is a fix for PR47630. The regression is caused by the D78011. After
this change the code starts to call the `emitGlobalConstantLargeInt` even
for constants which requires eight bytes to store.

Differential revision: https://reviews.llvm.org/D88261

This is like FastMathFlagGuard in IR. Since we use SDAG instance to get
values, it's with SelectionDAG. By creating a FlagInserter in current
scope, all values created by getNode will get the flags if no Flags
argument provided.

In this patch, I applied it to floating point operations folding part in
DAG combiner, and removed Flags passing to getNode to show its effect.
Other places in DAG combiner and other helper methods similar to getNode
also need this. They can be done in follow-up patches.

Reviewed By: spatel

Differential Revision: https://reviews.llvm.org/D87361

Differential Revision: https://reviews.llvm.org/D87187

Cleanup and add methods which https://reviews.llvm.org/D86904 requires. Breaking up to lower review load.

Reviewed By: mehdi_amini

Differential Revision: https://reviews.llvm.org/D88267

Previously for nowait target, CG emitted a function call to `__tgt_target_nowait`, etc. However, in OpenMP RTL, these functions just directly call the no-nowait version, which means nowait is not working as expected.

OpenMP specification says a target is acutally a target task, which is an untied and detachable task. It is natural to go to the direction that generates a task for a nowait target. However, OpenMP task has a problem that it must be within to a parallel region; otherwise the task will be executed immediately. As a result, if we directly wrap to a regular task, the `target nowait` outside of a parallel region is still a synchronous version.

In D77609, I added the support for unshackled task in OpenMP RTL. Basically, unshackled task is a task that is not bound to any parallel region. So all nowait target will be tranformed into an unshackled task. In order to distinguish from regular task, a new flag bit is set for unshackled task. This flag will be used by RTL for later process.

Since all target tasks are allocated via `__kmpc_omp_target_task_alloc`, and in current `libomptarget`, `__kmpc_omp_target_task_alloc` just calls `__kmpc_omp_task_alloc`. Therefore, we can modify the flag in `__kmpc_omp_target_task_alloc` so that we don't need to modify the FE too much. If users choose to opt out the feature, they just need to use a RTL w/o support of unshackled threads.

As a result, in this patch, the `target nowait` region is simply wrapped into a regular task. Later once we have RTL support for unshackled tasks, the wrapped tasks can be executed by unshackled threads w/o changes in the FE.

Reviewed By: jdoerfert

Differential Revision: https://reviews.llvm.org/D78075

Even if the type is s8/s16, assigning to gpr is preferable with constants because
worst case we can select via a constant pool load, and without cross-bank copies
to the FPR bank more patterns can be imported later.

This matches the legacy PM pass by having one constructor use command
line flags, and the other use parameters to the pass.

This fixes all tests under Transforms/LowerTypeTests using NPM.

Reviewed By: ychen, pcc

Differential Revision: https://reviews.llvm.org/D87845

Add the RISC-V Bullet core to the driver tests.

Add the pipeline model for the RISC-V Bullet micro architecture.

Co-authored-by: Evandro Menezes <evandro.menezes@sifive.com>

This patch performs a minor cleanup of the class Slice:
static methods and constructors which take a pointer but assume that
it's not null now take the argument by reference.
NFC.

Test plan: make check-all

Differential revision: https://reviews.llvm.org/D88320

[IR] Improve the description for Constant::isNormalFP to list all things that are not normal instead of just denormal. NFC

[LangRef] Clarify the behavior of memory access instructions when pointers/sizes aren't well-defined

This is a patch to LangRef that clarifies the behavior of load/store/memset/memcpy/memmove when the pointers or sizes are not well-defined
as well.

MSan detects a case when e.g., only lower bits of address are garbage when `-msan-check-access-address` is enabled, and it does not directly conflict with this patch because a C program should not use a pointer with undef bits and reasonable optimizations do not convert a well-defined pointer into a pointer with undef bits.

This patch contains a definition of a well-defined value as well.

Reviewed By: jdoerfert

Differential Revision: https://reviews.llvm.org/D87994

This commit fixes a regression (from LLVM 10 to LLVM 11 RC3) in the LLVM
C API.

Previously, commit 1ee6ec2b removed the mask operand from the
ShuffleVector instruction, storing the mask data separately in the
instruction instead; this reduced the number of operands of
ShuffleVector from 3 to 2. AFAICT, this change unintentionally caused
a regression in the LLVM C API. Specifically, it is no longer possible
to get the mask of a ShuffleVector instruction through the C API. This
patch introduces new functions which together allow a C API user to get
the mask of a ShuffleVector instruction, restoring the functionality
which was previously available through LLVMGetOperand().

This patch also adds tests for this change to the llvm-c-test
executable, which involved adding support for InsertElement,
ExtractElement, and ShuffleVector itself (as well as constant vectors)
to echo.cpp. Previously, vector operations weren't tested at all in
echo.ll.

I also fixed some typos in comments and help-text nearby these changes,
which I happened to spot while developing this patch. Since the typo
fixes are technically unrelated other than being in the same files, I'm
happy to take them out if you'd rather they not be included in the patch.

Differential Revision: https://reviews.llvm.org/D88190

Simplify and improve readability.

Differential Revision: https://reviews.llvm.org/D82269

The intrinsics don't have any pointer arguments, so "argmemonly" makes
optimizations think they don't write to memory at all.

Differential Revision: https://reviews.llvm.org/D88186