SPLASH 2020
Sun 15 - Sat 21 November 2020 Online Conference
Wed 18 Nov 2020 17:40 - 18:00 at OOPSLA/ECOOP - W-6
Thu 19 Nov 2020 05:40 - 06:00 at OOPSLA/ECOOP - W-6

This paper describes a compiler optimization to eliminates dynamic occurrences of expressions in the format $a = a \oplus b \otimes c$. The operation $\oplus$ must admit an identity element $z$, such that $a \oplus z = a$. Also, $z$ must be the absorbing element of $\otimes$, such that $b \otimes z = z \otimes c = z$. Semirings where $\oplus$ is the additive operator and $\otimes$ is the multiplicative operator meet this contract. This pattern is common in high-performance benchmarks—its canonical representative being the multiply-add operation $a = a + b \times c$. However, several other expressions involving arithmetic and logic operations satisfy the required algebra. We show that the runtime elimination of such assignments can be implemented in a performance-safe way via in-loco profiling. The elimination of dynamic redundancies involving identity and absorbing elements in the LLVM test suite brings an average speedup of 6% (geo-mean) and 19% (arith-mean) over clang -O3. When added onto clang, semiring optimizations approximates it to TACO, a specialized tensor compiler.

Wed 18 Nov
Times are displayed in time zone: Central Time (US & Canada) change

17:00 - 18:20: W-6OOPSLA at OOPSLA/ECOOP +12h
17:00 - 17:20
Talk
OOPSLA
Hila PelegUniversity of California, San Diego, Roi GabayTechnion, Shachar ItzhakyTechnion, Israel, Eran YahavTechnion
17:20 - 17:40
Talk
OOPSLA
Subarno BanerjeeUniversity of Michigan, David DevecseryGeorgia Institute of Technology, Peter M. ChenUniversity of Michigan, USA, Satish NarayanasamyUniversity of Michigan
17:40 - 18:00
Talk
OOPSLA
Guilherme LeobasUniversidade Federal de Minas Gerais, Fernando Magno Quintão PereiraUFMG
DOI Pre-print
18:00 - 18:20
Talk
OOPSLA
Yuting WangShanghai Jiao Tong University, Xiangzhe XuNanjing University, Pierre WILKECentraleSupelec Rennes, Zhong ShaoYale University

Thu 19 Nov
Times are displayed in time zone: Central Time (US & Canada) change

05:00 - 06:20: W-6OOPSLA at OOPSLA/ECOOP
05:00 - 05:20
Talk
OOPSLA
Hila PelegUniversity of California, San Diego, Roi GabayTechnion, Shachar ItzhakyTechnion, Israel, Eran YahavTechnion
05:20 - 05:40
Talk
OOPSLA
Subarno BanerjeeUniversity of Michigan, David DevecseryGeorgia Institute of Technology, Peter M. ChenUniversity of Michigan, USA, Satish NarayanasamyUniversity of Michigan
05:40 - 06:00
Talk
OOPSLA
Guilherme LeobasUniversidade Federal de Minas Gerais, Fernando Magno Quintão PereiraUFMG
DOI Pre-print
06:00 - 06:20
Talk
OOPSLA
Yuting WangShanghai Jiao Tong University, Xiangzhe XuNanjing University, Pierre WILKECentraleSupelec Rennes, Zhong ShaoYale University