Remove "approx-func-fp-math" attribute and related command line option,
users should always use afn flag in IR.
Resolve FIXME in `TargetMachine::resetTargetOptions` partially.

Linkers do not currently support PT_GNU_RELRO for SHF_X86_64_LARGE
sections; that would require the linker to emit more than one
PT_GNU_RELRO because large sections are discontiguous by design,
and most ELF dynamic loaders do not support that (bionic appears to
support it but glibc/musl/FreeBSD/NetBSD/OpenBSD appear not to). With
current linkers these sections will end up in .ldata which results
in silently disabling RELRO. Therefore, disable SHF_X86_64_LARGE for
RELRO sections. If this ever gets supported by downstream components
in the future we could add an opt-in flag for moving these sections
to .ldata.rel.ro which would trigger the creation of a second
PT_GNU_RELRO.

Reviewers: MaskRay, aeubanks

Reviewed By: aeubanks

Pull Request: https://github.com/llvm/llvm-project/pull/137742

I noticed these destructors taking time with -ftime-trace and moved some
of them for minor build efficiency improvements.

The main impact of moving destructors out of line is that it avoids
requiring container fields containing other types from being complete,
i.e. one can have uptr<T> or vector<T> as a field with an incomplete
type T, and that means we can reduce transitive includes, as with
LegalizerInfo.h.

Move expensive getDebugOperandsForReg template out-of-line. The
std::function instantiation shows up in time trace even if you don't use
the function.

This patch implements an LLVM IR pass, named kernel-info, that reports
various statistics for codes compiled for GPUs. The ultimate goal of
these statistics to help identify bad code patterns and ways to mitigate
them. The pass operates at the LLVM IR level so that it can, in theory,
support any LLVM-based compiler for programming languages supporting
GPUs. It has been tested so far with LLVM IR generated by Clang for
OpenMP offload codes targeting NVIDIA GPUs and AMD GPUs.

By default, the pass runs at the end of LTO, and options like
``-Rpass=kernel-info`` enable its remarks. Example `opt` and `clang`
command lines appear in `llvm/docs/KernelInfo.rst`. Remarks include
summary statistics (e.g., total size of static allocas) and individual
occurrences (e.g., source location of each alloca). Examples of its
output appear in tests in `llvm/test/Analysis/KernelInfo`.

This PR is necessary for cygwin target of Rust.

References:
*
https://github.com/rust-lang/llvm-project/commit/86657cc39f8e42ae73be810fb0703ddac0eeef94
*
https://github.com/Berrysoft/llvm-project/commit/a807e9f077351d3c6a68f4abe74c94a039759a2e

The others are already inline here.

Replace it with a forward declaration instead. Analysis.h is pulled in
by all passes, but not all passes need to access the module.

Similar to https://github.com/llvm/llvm-project/pull/96902, this adds
`getDataLayout()` helpers to Function and GlobalValue, replacing the
current `getParent()->getDataLayout()` pattern.

Following #78348, we should treat functions with an explicit section as
small, unless the section name is (or has the prefix) ".ltext".

Clang emits global initializers into a ".text.startup" section on Linux.
If we mix small/medium code model object files with large code model
object files, we'll end up mixing sections with and without the large
section flag.

Reland of #87838 with a check for non-ELF platforms in
TargetMachine::isLargeGlobalValue(), otherwise MCJIT on Windows tests
fail.

This reverts commit e27c3736f975ca463476223c465e4777186f603f.

Breaks ExecutionEngine/MCJIT/test-global-ctors.ll on windows, e.g. https://lab.llvm.org/buildbot/#/builders/117/builds/18749.