Ramon benchmark for Z3
-
Job description: 
Job tag: smt_qflia-threads-4-copilot-fix-verbose-lock-contention
Runner: lev-ripper
Z3 repo: Z3Prover/z3
Z3 commit: 3745bdd43b2b2349b1904c7d49eccd99ef11a188
Z3 branch: master
Z3 options: "-T:30 smt.threads=4 tactic.default_tactic=smt smt.auto_config=false"
Z3 inputs: inputs/QF_LIA
Z3 commit message: fix: reduce verbose lock contention in theory_diff_logic (issue #8019)

In multi-threaded solving, IF_VERBOSE(0, ...) in found_non_diff_logic_expr
was always acquiring the global g_verbose_mux mutex (since verbosity >= 0 is
always true) while holding it for potentially expensive mk_pp() calls. This
caused catastrophic lock contention when multiple threads internalized atoms.

Change IF_VERBOSE(0, ...) to IF_VERBOSE(2, ...) in both theory_diff_logic_def.h
and theory_dense_diff_logic_def.h. The diagnostic message is still available at
verbosity level 2 (-v:2), but is no longer printed (or locked) at the default
verbosity level, eliminating the contention.

Co-authored-by: levnach <5377127+levnach@users.noreply.github.com>
