cmd/compile: optimize sccp for faster convergence

[y1yang0]

While investigating other optimizations, I found several
opportunities to accelerate sccp convergence:

• Avoid adding duplicate uses to the re-visit worklist
• Prevent queueing uses of values that have already reached the Bottom
• Add an early exit when processing a value that is already Bottom

These changes provide an overall speedup of ~9% for sccp phase
during a full make.bash run. Also they does not change
the number of constants found or the amount of dead code eliminated.

Updates #77325

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Patch Set 1:

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[y1yang0]

Some raw data you may find useful(cnt_sorted_: number of constants found or the amount of dead code eliminated, time_sorted_*: phase time consumption)
time_sorted_new.log
time_sorted_new1.log
time_sorted_old.log
time_sorted_old1.log
cnt_sorted_new.log
cnt_sorted_old.log

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Patch Set 2:

(1 comment)

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Patch Set 2: Commit-Queue+1

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Patch Set 2:

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Patch Set 2: -Commit-Queue

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Patch Set 2:

This CL has failed the run. Reason:

Tryjob golang/try/x_tools-gotip-linux-amd64 has failed with summary (view all results):

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• go on master (change 740980) / tools on master (commit 955d132)

To reproduce, try gomote repro 8690994812547391489.

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Patch Set 2:

(3 comments)

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Patch Set 2:

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Patch Set 3:

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Patch Set 3: Commit-Queue+1

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