cmake

refactor: compact code layout #503

Job	Run time
linux_archs (i386, 386)	1m 58s
linux_archs (ppc64le, ppc64le)	12m 43s
linux_archs (arm64v8, arm64)	15m 54s
linux_archs (arm32v7, arm/v7)	17m 11s
linux_gcc4	1m 12s
linux_archs (riscv64, riscv64)	16m 8s
linux_archs (s390x, s390x)	15m 6s
linux_clang_latest	3m 7s
linux_gcc5_i386	1m 35s
linux_checks (Release, Default, Valgrind)	2m 59s
linux_checks (Debug, ReduceBinary, Valgrind)	8m 31s
linux_checks (Debug, Default, Valgrind)	9m 53s
linux_checks (Debug, Default, Sanitizer)	3m 56s
linux_checks (Debug, ReduceBinary, Sanitizer)	1m 20s
linux_checks (Release, Default, Sanitizer)	2m 31s
linux_tinycc	2m 45s
linux_checks (MinSizeRel, ReduceBinary, Sanitizer)	1m 29s
linux_opts (clang, no_fp)	41s
linux_gcc_latest	3m 8s
linux_checks (MinSizeRel, Default, Valgrind)	3m 22s
linux_opts (clang, no_utf8)	52s
linux_opts (clang, no_writer)	32s
linux_checks (MinSizeRel, ReduceBinary, Valgrind)	7m 39s
linux_checks (Release, ReduceBinary, Valgrind)	7m 28s
linux_opts (gcc, no_utf8)	1m 30s
linux_checks (MinSizeRel, Default, Sanitizer)	1m 47s
linux_checks (Release, ReduceBinary, Sanitizer)	1m 39s
macos_clang	47s
fuzzing	5m 25s
linux_opts (clang, no_reader)	29s
codecov	2m 2s
linux_opts (gcc, no_writer)	44s
windows_msvc	2m 5s
linux_opts (gcc, no_reader)	29s
linux_opts (gcc, no_fp)	54s
	2h 39m 51s

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