getMaximum() and getMinimum(), called during parsing, create new
QDateTime instances, which on Linux end up calling mktime().
Making these static (for the common case of LocalTime spec)
improves performance dramatically, when parsing several date/times.
tests/benchmarks/corelib/tools/qdatetime/ (after fixing it to
actually parse a valid date/time) says:
RESULT : tst_QDateTime::fromString():
- 36,742,060 instruction reads per iteration (total: 36,742,060, iterations: 1)
+ 24,230,060 instruction reads per iteration (total: 24,230,060, iterations: 1)
Change-Id: I0c3931285475bf19a5be8cba1486ed07cbf5e134
Reviewed-by: Thiago Macieira <thiago.macieira@intel.com>
a8ae8e3130