#12545: Compilation time/space regression in GHC 8.0/8.1 (search in type-level lists and -O) -------------------------------------+------------------------------------- Reporter: | Owner: mikhail.vorozhtsov | Type: bug | Status: new Priority: normal | Milestone: Component: Compiler | Version: 8.0.1 Resolution: | Keywords: Inlining Operating System: Unknown/Multiple | Architecture: Type of failure: Compile-time | Unknown/Multiple performance bug | Test Case: Blocked By: | Blocking: Related Tickets: | Differential Rev(s): Wiki Page: | -------------------------------------+------------------------------------- Comment (by mikhail.vorozhtsov): Here are some numbers from `-v4` logs: {{{ $ grep -E '(=====|^Result|coercions)' out-7_10.log | grep -v 'RHS size' | head -40 ==================== Parser ==================== ==================== Source Statistics ==================== ==================== Occurrence analysis ==================== ==================== Desugar (after optimization) ==================== Result size of Desugar (after optimization) = {terms: 2,144, types: 128,368, coercions: 415,496} ==================== Occurrence analysis ==================== Result size of Simplifier iteration=1 = {terms: 3,200, types: 173,424, coercions: 415,528} ==================== Occurrence analysis ==================== Result size of Simplifier = {terms: 3,200, types: 173,424, coercions: 415,528} ==================== Specialise ==================== Result size of Specialise = {terms: 12,416, types: 658,320, coercions: 455,704} ==================== FloatOut stats: ==================== Result size of Float out(FOS {Lam = Just 0, = {terms: 13,472, types: 739,808, coercions: 455,704} ==================== Occurrence analysis ==================== Result size of Simplifier iteration=1 = {terms: 30,336, types: 1,848,096, coercions: 6,417,128} ==================== Occurrence analysis ==================== Result size of Simplifier = {terms: 30,336, types: 1,848,096, coercions: 6,417,128} ==================== Occurrence analysis ==================== Result size of Simplifier = {terms: 30,336, types: 1,848,096, coercions: 6,417,128} ==================== Occurrence analysis ==================== Result size of Simplifier = {terms: 30,336, types: 1,848,096, coercions: 6,417,128} Result size of Float inwards = {terms: 30,336, types: 1,848,096, coercions: 6,417,128} ==================== Called arity analysis ==================== Result size of Called arity analysis = {terms: 30,336, types: 1,848,096, coercions: 6,417,128} ==================== Occurrence analysis ==================== }}} for 7.10.3 versus {{{ $ grep -E '(=====|^Result|coercions)' out-8_0.log | grep -v 'RHS size' | head -40 ==================== Parser ==================== ==================== Source Statistics ==================== ==================== Occurrence analysis ==================== ==================== Desugar (after optimization) ==================== Result size of Desugar (after optimization) = {terms: 3,835, types: 147,262, coercions: 549,848} ==================== Occurrence analysis ==================== Result size of Simplifier iteration=1 = {terms: 4,897, types: 161,681, coercions: 549,849} ==================== Occurrence analysis ==================== Result size of Simplifier = {terms: 4,897, types: 161,681, coercions: 549,849} ==================== Specialise ==================== Result size of Specialise = {terms: 17,793, types: 899,977, coercions: 3,094,577} ==================== FloatOut stats: ==================== Result size of Float out(FOS {Lam = Just 0, = {terms: 20,769, types: 1,109,785, coercions: 3,094,577} ==================== Occurrence analysis ==================== Result size of Simplifier iteration=1 = {terms: 16,553, types: 871,953, coercions: 2,232,281} ==================== Occurrence analysis ==================== Result size of Simplifier = {terms: 16,429, types: 864,761, coercions: 2,184,448} ==================== Occurrence analysis ==================== Result size of Simplifier = {terms: 16,429, types: 864,761, coercions: 2,184,448} ==================== Occurrence analysis ==================== Result size of Simplifier iteration=1 = {terms: 87,357, types: 4,366,893, coercions: 10,008,352} ==================== Occurrence analysis ==================== Result size of Simplifier = {terms: 87,357, types: 4,366,893, coercions: 10,008,352} Result size of Float inwards = {terms: 87,357, types: 4,366,893, coercions: 10,008,352} ==================== Called arity analysis ==================== Result size of Called arity analysis = {terms: 87,357, types: 4,366,893, coercions: 10,008,352} ==================== Occurrence analysis ==================== }}} for 8.0.1 -- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/12545#comment:6 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler