forall_operands should not trigger any non-const operations

[tautschnig]

If .operands() is used in a non-const context, an unnecessary
(temporary) copy of the irep is created. Use as_const to avoid this.

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[codecov]

Codecov Report

Merging #5553 (a11293d) into develop (27f2a8a) will not change coverage.
The diff coverage is n/a.

@@           Coverage Diff            @@
##           develop    #5553   +/-   ##
========================================
  Coverage    68.53%   68.53%           
========================================
  Files         1187     1187           
  Lines        98263    98263           
========================================
  Hits         67347    67347           
  Misses       30916    30916           

Flag	Coverage Δ
cproversmt2	43.09% <ø> (ø)
regression	65.71% <ø> (ø)
unit	32.26% <ø> (ø)

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Impacted Files	Coverage Δ
src/util/expr.h	90.69% <ø> (ø)
src/util/simplify_utils.cpp	100.00% <ø> (ø)
src/util/std_expr.h	89.48% <ø> (ø)

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[kroening]

It's likely beneficial to remove the if((expr).has_operands()) line.

The reason why this was added was that .operands() might have added a named operands sub-node, which no longer exists.

[tautschnig]

It's likely beneficial to remove the if((expr).has_operands()) line.

Indeed, thank you!