Create AsyncResult class

[tclinkenbeard-oai]

Because Future<T> uses SAV<T> under the hood, if a coroutine returns a Future<T> the only way to take ownership of the result of the coroutine is to copy a T object, which may be expensive. In many cases, this is unnecessary, and should be avoided. For example, the following code requires an expensive copy:

Future<std::vector<int>> coro() {
  ...
  co_return largeVec;
}

Future<Void> caller() {
  auto const vec = co_await coro();
  ...
}

The new AsyncResult class is not copyable and doesn't rely on SAV, so results are moved out of the coroutine. If the coro coroutine above returned AsyncResult<std::vector<int>>, an expensive copy could be avoided. A microbenchmark is added in this PR to demonstrate this. fdbcli/ExcludeCommand.cpp is also updated to avoid some expensive copies using this optimization. Lastly, race is updated to support AsyncResult arguments as well as Future or FutureStream arguments.

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[foundationdb-ci]

Result of foundationdb-pr-clang on Linux RHEL 9

• Commit ID: 29735de
• Duration 0:04:08
• Result: ❌ FAILED
• Error: Error while executing command: if [[ $(git diff --shortstat 2> /dev/null | tail -n1) == "" ]]; then echo "CODE FORMAT CLEAN"; else echo "CODE FORMAT NOT CLEAN"; echo; echo "THE FOLLOWING FILES NEED TO BE FORMATTED"; echo; git ls-files -m; echo; if [[ $FDB_VERSION =~ 7\.\3. ]]; then echo skip; else exit 1; fi; fi. Reason: exit status 1
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[foundationdb-ci]

Result of foundationdb-pr on Linux RHEL 9

• Commit ID: 29735de
• Duration 0:04:16
• Result: ❌ FAILED
• Error: Error while executing command: if [[ $(git diff --shortstat 2> /dev/null | tail -n1) == "" ]]; then echo "CODE FORMAT CLEAN"; else echo "CODE FORMAT NOT CLEAN"; echo; echo "THE FOLLOWING FILES NEED TO BE FORMATTED"; echo; git ls-files -m; echo; if [[ $FDB_VERSION =~ 7\.\3. ]]; then echo skip; else exit 1; fi; fi. Reason: exit status 1
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[foundationdb-ci]

Result of foundationdb-pr-clang-arm on Linux CentOS 7

• Commit ID: 29735de
• Duration 0:04:20
• Result: ❌ FAILED
• Error: Error while executing command: if [[ $(git diff --shortstat 2> /dev/null | tail -n1) == "" ]]; then echo "CODE FORMAT CLEAN"; else echo "CODE FORMAT NOT CLEAN"; echo; echo "THE FOLLOWING FILES NEED TO BE FORMATTED"; echo; git ls-files -m; echo; if [[ $FDB_VERSION =~ 7\.\3. ]]; then echo skip; else exit 1; fi; fi. Reason: exit status 1
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[foundationdb-ci]

Result of foundationdb-pr-clang-ide on Linux RHEL 9

• Commit ID: 29735de
• Duration 0:04:24
• Result: ❌ FAILED
• Error: Error while executing command: if [[ $(git diff --shortstat 2> /dev/null | tail -n1) == "" ]]; then echo "CODE FORMAT CLEAN"; else echo "CODE FORMAT NOT CLEAN"; echo; echo "THE FOLLOWING FILES NEED TO BE FORMATTED"; echo; git ls-files -m; echo; if [[ $FDB_VERSION =~ 7\.\3. ]]; then echo skip; else exit 1; fi; fi. Reason: exit status 1
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[foundationdb-ci]

Result of foundationdb-pr-cluster-tests on Linux RHEL 9

• Commit ID: 29735de
• Duration 0:04:44
• Result: ❌ FAILED
• Error: Error while executing command: if [[ $(git diff --shortstat 2> /dev/null | tail -n1) == "" ]]; then echo "CODE FORMAT CLEAN"; else echo "CODE FORMAT NOT CLEAN"; echo; echo "THE FOLLOWING FILES NEED TO BE FORMATTED"; echo; git ls-files -m; echo; if [[ $FDB_VERSION =~ 7\.\3. ]]; then echo skip; else exit 1; fi; fi. Reason: exit status 1
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[foundationdb-ci]

Result of foundationdb-pr-clang-ide on Linux RHEL 9

• Commit ID: 848887b
• Duration 0:32:32
• Result: ✅ SUCCEEDED
• Error: N/A
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[foundationdb-ci]

Result of foundationdb-pr-clang-arm on Linux CentOS 7

• Commit ID: 848887b
• Duration 0:40:13
• Result: ✅ SUCCEEDED
• Error: N/A
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[foundationdb-ci]

Result of foundationdb-pr on Linux RHEL 9

• Commit ID: 848887b
• Duration 1:03:29
• Result: ✅ SUCCEEDED
• Error: N/A
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[foundationdb-ci]

Result of foundationdb-pr-clang on Linux RHEL 9

• Commit ID: 848887b
• Duration 1:04:23
• Result: ✅ SUCCEEDED
• Error: N/A
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[foundationdb-ci]

Result of foundationdb-pr-cluster-tests on Linux RHEL 9

• Commit ID: 848887b
• Duration 1:52:09
• Result: ✅ SUCCEEDED
• Error: N/A
• Build Log terminal output (available for 30 days)
• Build Workspace zip file of the working directory (available for 30 days)
• Cluster Test Logs zip file of the test logs (available for 30 days)

[gxglass]

(Review in progress)

[gxglass]

At best a partial review (limited template metaprogramming knowledge, limited knowledge of the code being modified), but doing what I can here.

[gxglass]

I might be missing something but this doesn't call release() while operator= below does. Is the difference intentional?

[gxglass]

would readers of this code generally know what F and U refer to here? If not put comments

[gxglass]

If there's a bug in this logic, or let's say this line got deleted by merge damage (unlikely, but possible), would that fail any tests?