Summary: Intel's HRC (Haskell Research Compiler) is an optimizing compiler for GHC's (Glasgow Haskell Compiler) "Core" intermediate language.* On six common benchmarks, it improves the performance of Haskell dramatically. But Haskell is still 4 times slower than the best C implementations of these benchmarks, on average.
* Core is just desugared Haskell and should not be confused with GHC's other intermediate languages, STG and C--. And there is no relation to Intel's "Core" microarchitecture.
* Core is just desugared Haskell and should not be confused with GHC's other intermediate languages, STG and C--. And there is no relation to Intel's "Core" microarchitecture.