#13397: Optimise calls to tagToEnum# -------------------------------------+------------------------------------- Reporter: simonpj | Owner: (none) Type: bug | Status: new Priority: normal | Milestone: Component: Compiler | Version: 8.0.1 Resolution: | Keywords: Operating System: Unknown/Multiple | Architecture: | Unknown/Multiple Type of failure: None/Unknown | Test Case: Blocked By: | Blocking: Related Tickets: | Differential Rev(s): Wiki Page: | -------------------------------------+------------------------------------- Comment (by dfeuer): Simon, I rebased your branch and fixed a comment, producing `wip/dfeuer-T13397`. The [https://perf.haskell.org/ghc/#compare/583fa9e3687b49d8c779e6d53a75af9276e4f5... perf results] generally look fine, with a few very small regressions: {{{ Nofib allocations ----------------- knights +1.35% pic +1.14% scs +0.81% (this ran slightly *faster*) last-piece +0.29% Nofib runtimes -------------- cacheprof +1.3% last-piece +1.23% hidden +1.08% wheel-sieve1 +0.95% digits-of-e1 +0.87% lambda +0.47% Test suite allocations ---------------------- T783 +0.59% T9675 +0.33% T12707 +0.23% }}} The wins seem modest, but bigger than the regressions: {{{ Nofib allocations ----------------- anna -0.7% fft -0.41% Nofib runtimes -------------- cryptarithm1 -4.29% fannkuch-redux -3.75% binary-trees -3.7% scs -1.28% integer -1% fasta -0.98% mate -0.95% digits-of-e2 -0.85% }}} As far as I'm concerned, this should probably be ready to merge. Should I do so? -- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/13397#comment:6 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler