08e40c12fa
Reapply #147854 after fixes merged in #151398. Change memory access histogram storage from uint64_t to uint16_t to reduce profile size on disk. This change updates the raw profile format to v5. Also add a histogram test in compiler-rt since we didn't have one before. With this change the histogram memprof raw for the basic test reduces from 75KB -> 20KB.
Compiler-RT ================================ This directory and its subdirectories contain source code for the compiler support routines. Compiler-RT is open source software. You may freely distribute it under the terms of the license agreement found in LICENSE.txt. ================================