[test] Remove some legacy PM tests in llvm/test/Instrumentation

[IR][sanitizer] Set nounwind on module ctor/dtor, additionally set uwtable if -fasynchronous-unwind-tables

On ELF targets, if a function has uwtable or personality, or does not have
nounwind (`needs

[IR][sanitizer] Set nounwind on module ctor/dtor, additionally set uwtable if -fasynchronous-unwind-tables

On ELF targets, if a function has uwtable or personality, or does not have
nounwind (`needsUnwindTableEntry`), it marks that `.eh_frame` is needed in the module.

Then, a function gets `.eh_frame` if `needsUnwindTableEntry` or `-g[123]` is specified.
(i.e. If -g[123], every function gets `.eh_frame`.
This behavior is strange but that is the status quo on GCC and Clang.)

Let's take asan as an example. Other sanitizers are similar.
`asan.module_[cd]tor` has no attribute. `needsUnwindTableEntry` returns true,
so every function gets `.eh_frame` if `-g[123]` is specified.
This is the root cause that
`-fno-exceptions -fno-asynchronous-unwind-tables -g` produces .debug_frame
while
`-fno-exceptions -fno-asynchronous-unwind-tables -g -fsanitize=address` produces .eh_frame.

This patch

* sets the nounwind attribute on sanitizer module ctor/dtor.
* let Clang emit a module flag metadata "uwtable" for -fasynchronous-unwind-tables. If "uwtable" is set, sanitizer module ctor/dtor additionally get the uwtable attribute.

The "uwtable" mechanism is generic: synthesized functions not cloned/specialized
from existing ones should consider `Function::createWithDefaultAttr` instead of
`Function::create` if they want to get some default attributes which
have more of module semantics.

Other candidates: "frame-pointer" (https://github.com/ClangBuiltLinux/linux/issues/955
https://github.com/ClangBuiltLinux/linux/issues/1238), dso_local, etc.

Differential Revision: https://reviews.llvm.org/D100251

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[NewPM][Sancov] Pin RUN lines with -sancov to legacy PM

Since the NPM pass is named sancov-module, not sancov.
This makes all tests under Instrumentation/SanitizerCoverage pass when
-enable-new-pm i

[NewPM][Sancov] Pin RUN lines with -sancov to legacy PM

Since the NPM pass is named sancov-module, not sancov.
This makes all tests under Instrumentation/SanitizerCoverage pass when
-enable-new-pm is on by default.

Reviewed By: vitalybuka

Differential Revision: https://reviews.llvm.org/D84687

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[NewPM][Sancov] Make Sancov a Module Pass instead of 2 Passes

This patch merges the sancov module and funciton passes into one module pass.

The reason for this is because we ran into an out of memo

[NewPM][Sancov] Make Sancov a Module Pass instead of 2 Passes

This patch merges the sancov module and funciton passes into one module pass.

The reason for this is because we ran into an out of memory error when
attempting to run asan fuzzer on some protobufs (pc.cc files). I traced the OOM
error to the destructor of SanitizerCoverage where we only call
appendTo[Compiler]Used which calls appendToUsedList. I'm not sure where precisely
in appendToUsedList causes the OOM, but I am able to confirm that it's calling
this function *repeatedly* that causes the OOM. (I hacked sancov a bit such that
I can still create and destroy a new sancov on every function run, but only call
appendToUsedList after all functions in the module have finished. This passes, but
when I make it such that appendToUsedList is called on every sancov destruction,
we hit OOM.)

I don't think the OOM is from just adding to the SmallSet and SmallVector inside
appendToUsedList since in either case for a given module, they'll have the same
max size. I suspect that when the existing llvm.compiler.used global is erased,
the memory behind it isn't freed. I could be wrong on this though.

This patch works around the OOM issue by just calling appendToUsedList at the
end of every module run instead of function run. The same amount of constants
still get added to llvm.compiler.used, abd we make the pass usage and logic
simpler by not having any inter-pass dependencies.

Differential Revision: https://reviews.llvm.org/D66988

llvm-svn: 370971

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Reland the "[NewPM] Port Sancov" patch from rL365838. No functional
changes were made to the patch since then.

--------

[NewPM] Port Sancov

This patch contains a port of SanitizerCoverage to the n

Reland the "[NewPM] Port Sancov" patch from rL365838. No functional
changes were made to the patch since then.

--------

[NewPM] Port Sancov

This patch contains a port of SanitizerCoverage to the new pass manager. This one's a bit hefty.

Changes:

- Split SanitizerCoverageModule into 2 SanitizerCoverage for passing over
functions and ModuleSanitizerCoverage for passing over modules.
- ModuleSanitizerCoverage exists for adding 2 module level calls to initialization
functions but only if there's a function that was instrumented by sancov.
- Added legacy and new PM wrapper classes that own instances of the 2 new classes.
- Update llvm tests and add clang tests.

llvm-svn: 367053

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Revert "[NewPM] Port Sancov"

This reverts commit 5652f35817f07b16f8b3856d594cc42f4d7ee29c.

llvm-svn: 366153

[NewPM] Port Sancov

This patch contains a port of SanitizerCoverage to the new pass manager. This one's a bit hefty.

Changes:

- Split SanitizerCoverageModule into 2 SanitizerCoverage for passing o

[NewPM] Port Sancov

This patch contains a port of SanitizerCoverage to the new pass manager. This one's a bit hefty.

Changes:

- Split SanitizerCoverageModule into 2 SanitizerCoverage for passing over
functions and ModuleSanitizerCoverage for passing over modules.
- ModuleSanitizerCoverage exists for adding 2 module level calls to initialization
functions but only if there's a function that was instrumented by sancov.
- Added legacy and new PM wrapper classes that own instances of the 2 new classes.
- Update llvm tests and add clang tests.

Differential Revision: https://reviews.llvm.org/D62888

llvm-svn: 365838

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[SanitizerCoverage] Use different module ctor names for trace-pc-guard and inline-8bit-counters

Fixes the main issue in PR41693

When both modes are used, two functions are created:
`sancov.module_c

[SanitizerCoverage] Use different module ctor names for trace-pc-guard and inline-8bit-counters

Fixes the main issue in PR41693

When both modes are used, two functions are created:
`sancov.module_ctor`, `sancov.module_ctor.$LastUnique`, where
$LastUnique is the current LastUnique counter that may be different in
another module.

`sancov.module_ctor.$LastUnique` belongs to the comdat group of the same
name (due to the non-null third field of the ctor in llvm.global_ctors).

COMDAT group section [ 9] `.group' [sancov.module_ctor] contains 6 sections:
[Index] Name
[ 10] .text.sancov.module_ctor
[ 11] .rela.text.sancov.module_ctor
[ 12] .text.sancov.module_ctor.6
[ 13] .rela.text.sancov.module_ctor.6
[ 23] .init_array.2
[ 24] .rela.init_array.2

# 2 problems:
# 1) If sancov.module_ctor in this module is discarded, this group
# has a relocation to a discarded section. ld.bfd and gold will
# error. (Another issue: it is silently accepted by lld)
# 2) The comdat group has an unstable name that may be different in
# another translation unit. Even if the linker allows the dangling relocation
# (with --noinhibit-exec), there will be many undesired .init_array entries
COMDAT group section [ 25] `.group' [sancov.module_ctor.6] contains 2 sections:
[Index] Name
[ 26] .init_array.2
[ 27] .rela.init_array.2

By using different module ctor names, the associated comdat group names
will also be different and thus stable across modules.

Reviewed By: morehouse, phosek

Differential Revision: https://reviews.llvm.org/D61510

llvm-svn: 360107

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