Microoptimize QObject::activate.
This patch removes temporary variables that are not used in all cases.
This reduces the instruction count per iteration for the corresponding
benchmark by 1 or 2.
Before:
********* Start testing of QObjectBenchmark *********
Config: Using QtTest library 5.7.0, Qt 5.7.0 (x86_64-little_endian-lp64 shared (dynamic) release build; by GCC 5.3.0)
PASS : QObjectBenchmark::initTestCase()
PASS : QObjectBenchmark::signal_slot_benchmark(simple function)
RESULT : QObjectBenchmark::signal_slot_benchmark():"simple function":
21.0065466 instructions per iteration (total: 210,065,466, iterations: 10000000)
PASS : QObjectBenchmark::signal_slot_benchmark(single signal/slot)
RESULT : QObjectBenchmark::signal_slot_benchmark():"single signal/slot":
405.0829559 instructions per iteration (total: 4,050,829,559, iterations: 10000000)
PASS : QObjectBenchmark::signal_slot_benchmark(multi signal/slot)
RESULT : QObjectBenchmark::signal_slot_benchmark():"multi signal/slot":
405.0812465 instructions per iteration (total: 4,050,812,465, iterations: 10000000)
PASS : QObjectBenchmark::signal_slot_benchmark(unconnected signal)
RESULT : QObjectBenchmark::signal_slot_benchmark():"unconnected signal":
104.0147348 instructions per iteration (total: 1,040,147,349, iterations: 10000000)
PASS : QObjectBenchmark::signal_slot_benchmark(single signal/ptr)
RESULT : QObjectBenchmark::signal_slot_benchmark():"single signal/ptr":
369.1021099 instructions per iteration (total: 3,691,021,100, iterations: 10000000)
PASS : QObjectBenchmark::signal_slot_benchmark(functor)
RESULT : QObjectBenchmark::signal_slot_benchmark():"functor":
370.0982862 instructions per iteration (total: 3,700,982,862, iterations: 10000000)
PASS : QObjectBenchmark::cleanupTestCase()
Totals: 8 passed, 0 failed, 0 skipped, 0 blacklisted, 6036ms
********* Finished testing of QObjectBenchmark *********
After:
********* Start testing of QObjectBenchmark *********
Config: Using QtTest library 5.7.0, Qt 5.7.0 (x86_64-little_endian-lp64 shared (dynamic) release build; by GCC 5.3.0)
PASS : QObjectBenchmark::initTestCase()
PASS : QObjectBenchmark::signal_slot_benchmark(simple function)
RESULT : QObjectBenchmark::signal_slot_benchmark():"simple function":
21.0061664 instructions per iteration (total: 210,061,664, iterations: 10000000)
PASS : QObjectBenchmark::signal_slot_benchmark(single signal/slot)
RESULT : QObjectBenchmark::signal_slot_benchmark():"single signal/slot":
403.0829161 instructions per iteration (total: 4,030,829,162, iterations: 10000000)
PASS : QObjectBenchmark::signal_slot_benchmark(multi signal/slot)
RESULT : QObjectBenchmark::signal_slot_benchmark():"multi signal/slot":
403.0836305 instructions per iteration (total: 4,030,836,305, iterations: 10000000)
PASS : QObjectBenchmark::signal_slot_benchmark(unconnected signal)
RESULT : QObjectBenchmark::signal_slot_benchmark():"unconnected signal":
104.0150038 instructions per iteration (total: 1,040,150,039, iterations: 10000000)
PASS : QObjectBenchmark::signal_slot_benchmark(single signal/ptr)
RESULT : QObjectBenchmark::signal_slot_benchmark():"single signal/ptr":
368.0981987 instructions per iteration (total: 3,680,981,988, iterations: 10000000)
PASS : QObjectBenchmark::signal_slot_benchmark(functor)
RESULT : QObjectBenchmark::signal_slot_benchmark():"functor":
369.1179429 instructions per iteration (total: 3,691,179,429, iterations: 10000000)
PASS : QObjectBenchmark::cleanupTestCase()
Totals: 8 passed, 0 failed, 0 skipped, 0 blacklisted, 5975ms
********* Finished testing of QObjectBenchmark *********
Change-Id: Iba3bffbca5b58109816c8b1a7dea0796b18c8785
Reviewed-by: Olivier Goffart (Woboq GmbH) <ogoffart@woboq.com>
bd35260415