Mem optimize #853

Job	Run time
clang-format	6m 16s
Coverage (STP)	38m 0s
Docker	11m 27s
Coverage (Z3)	48m 20s
Linux (LLVM 14)	16m 53s
Linux (LLVM 13)	15m 50s
macOS	10m 51s
Linux (LLVM 12)	15m 24s
Linux (LLVM 11, Doxygen)	22m 14s
Linux (LLVM 10)	21m 29s
Linux (LLVM 9)	15m 7s
Linux (ASan)	1h 13m 50s
Linux (UBSan)	46m 48s
Linux (MSan)	53m 55s
Linux (Z3 only)	22m 31s
Linux (metaSMT)	32m 6s
Linux (STP master)	19m 13s
Linux (Latest klee-uclibc)	16m 51s
Linux (Asserts disabled)	15m 35s
Linux (No TCMalloc, optimised runtime)	19m 26s
	8h 42m 6s

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