[MemProf] Minor fixes to dot graph printing (#128217)
Two misc cleanup/improvements to the dot printing.
Remove a redundant "style=filled" in the Node attributes. No effect on
resulting graph.
Add a "color" attribute to the Edge, with the same color name as
"fillcolor". The latter only fills in the arrowhead, and the former is
what affects the line. This makes the edge colors more visible,
previously it was a black edge with a colored in arrowhead.
For the second change, I added the new Edge color attributes to the
checking in the two "basic.ll" tests, so we get some testing coverage of
the full printing. For the other affected tests I removed the final "]'"
after the fillcolor so it matches up through that attribute and ignores
the rest of the line.
[MemProf] Control availability of hot/cold operator new from LTO link
Adds an LTO option to indicate that whether we are linking with an
allocator that supports hot/cold operator new interfaces. If not,
at the start of the LTO backends any existing memprof hot/cold
attributes are removed from the IR, and we also remove memprof metadata
so that post-LTO inlining doesn't add any new attributes.
This is done via setting a new flag in the module summary index. It is
important to communicate via the index to the LTO backends so that
distributed ThinLTO handles this correctly, as they are invoked by
separate clang processes and the combined index is how we communicate
information from the LTO link. Specifically, for distributed ThinLTO the
LTO related processes look like:
```
# Thin link:
$ lld --thinlto-index-only obj1.o ... objN.o -llib ...
# ThinLTO backends:
$ clang -x ir obj1.o -fthinlto-index=obj1.o.thinlto.bc -c -O2
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Revert "[MemProf] Context disambiguation cloning pass [patch 3/4]"
This reverts commit bf6ff4fd4b735afffc65f92a4a79f6610e7174c3.
There is a bot failure where we are getting the correct remarks output
but in a different order. I'll need to investigate to see where we are
having nondeterministic behavior.
[MemProf] Context disambiguation cloning pass [patch 3/4]
Applies cloning decisions to the IR, cloning functions and updating
calls. For Regular LTO, the IR is updated directly during function
assignment, whereas for ThinLTO it is recorded in the summary index
(a subsequent patch will apply to the IR via the index during the
ThinLTO backend.
The function assignment and cloning proceeds greedily, and we create new
clones as needed when we find an incompatible assignment of function
clones to callsite clones (i.e. when different callers need to invoke
different combinations of callsite clones).
Depends on D140949.
Differential Revision: https://reviews.llvm.org/D141077
[MemProf] Use profiled lifetime access density directly
Now that the runtime tracks the lifetime access density directly, we can
use that directly in the threshold checks instead of less accurately
computing from other statistics.
Differential Revision: https://reviews.llvm.org/D149684
