[InstCombine] Infer nusw + nneg -> nuw for getelementptr (#111144)

If the gep is nusw (usually via inbounds) and the offset is
non-negative, we can infer nuw.

Proof: https://alive2.llvm.org/ce/z

[InstCombine] Infer nusw + nneg -> nuw for getelementptr (#111144)

If the gep is nusw (usually via inbounds) and the offset is
non-negative, we can infer nuw.

Proof: https://alive2.llvm.org/ce/z/ihztLy

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[Clang] Enable -fpointer-tbaa by default. (#117244)

Support for more precise TBAA metadata has been added a while ago
(behind the -fpointer-tbaa flag). The more precise TBAA metadata allows
treati

[Clang] Enable -fpointer-tbaa by default. (#117244)

Support for more precise TBAA metadata has been added a while ago
(behind the -fpointer-tbaa flag). The more precise TBAA metadata allows
treating accesses of different pointer types as no-alias.

This helps to remove more redundant loads and stores in a number of
workloads.

Some highlights on the impact across llvm-test-suite's MultiSource,
SPEC2006 & SPEC2017 include:
* +2% more NoAlias results for memory accesses
* +3% more stores removed by DSE,
* +4% more loops vectorized.

This closes a relatively big gap to GCC, which has been supporting
disambiguating based on pointer types for a long time.
(https://clang.godbolt.org/z/K7Wbhrz4q)

Pointer-TBAA support for pointers to builtin types has been added in
https://github.com/llvm/llvm-project/pull/76612.

Support for user-defined types has been added in
https://github.com/llvm/llvm-project/pull/110569.

There are 2 recent PRs with bug fixes for special cases uncovered during
testing:
* https://github.com/llvm/llvm-project/pull/116991
* https://github.com/llvm/llvm-project/pull/116596

PR: https://github.com/llvm/llvm-project/pull/117244

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Codegen changes for strict modifier with grainsize/num_tasks of taskloop construct (#117196)

Initial parsing/sema for 'strict' modifier with 'num_tasks' and
‘grainsize’ clause is present in these c

Codegen changes for strict modifier with grainsize/num_tasks of taskloop construct (#117196)

Initial parsing/sema for 'strict' modifier with 'num_tasks' and
‘grainsize’ clause is present in these commits
[grainsize_parsing](https://github.com/llvm/llvm-project/commit/ab9eac762c35068e77f57795e660d06f578c9614)
and
[num_tasks_parsing](https://github.com/llvm/llvm-project/commit/56c166017055595a9f26933e85bfd89e30c528d0#diff-4184486638e85284c3a2c961a81e7752231022daf97e411007c13a6732b50db9R6545)
. However, this implementation appears incomplete as it lacks code
generation support. A runtime patch was introduced in this runtime
commit
[runtime_patch](https://github.com/llvm/llvm-project/commit/540007b42701b5ac9adba076824bfd648a265413#diff-5e95f9319910d6965d09c301359dbe6b23f3eef5ce4d262ef2c2d2137875b5c4R374)
, which adds a new API, _kmpc_taskloop_5, to accommodate the strict
modifier. 
In this patch I have added codegen support. When the strict modifier is
present alongside the grainsize or num_tasks clauses of taskloop
construct, the code now emits a call to _kmpc_taskloop_5, which includes
an additional parameter of type i32 with the value 1 to indicate the
strict modifier. If the strict modifier is not present, it falls back to
the existing _kmpc_taskloop API call.

---------

Co-authored-by: Chandra Ghale <ghale@pe31.hpc.amslabs.hpecorp.net>

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