diff options
Diffstat (limited to 'compiler/prelude/PrelRules.hs')
| -rw-r--r-- | compiler/prelude/PrelRules.hs | 45 |
1 files changed, 33 insertions, 12 deletions
diff --git a/compiler/prelude/PrelRules.hs b/compiler/prelude/PrelRules.hs index ffee79da36..370a026768 100644 --- a/compiler/prelude/PrelRules.hs +++ b/compiler/prelude/PrelRules.hs @@ -1206,7 +1206,10 @@ builtinRules :: [CoreRule] builtinRules = [BuiltinRule { ru_name = fsLit "AppendLitString", ru_fn = unpackCStringFoldrName, - ru_nargs = 4, ru_try = match_append_lit }, + ru_nargs = 4, ru_try = match_append_lit_C }, + BuiltinRule { ru_name = fsLit "AppendLitStringUtf8", + ru_fn = unpackCStringFoldrUtf8Name, + ru_nargs = 4, ru_try = match_append_lit_utf8 }, BuiltinRule { ru_name = fsLit "EqString", ru_fn = eqStringName, ru_nargs = 2, ru_try = match_eq_string }, BuiltinRule { ru_name = fsLit "Inline", ru_fn = inlineIdName, @@ -1378,11 +1381,22 @@ builtinNaturalRules = --------------------------------------------------- -- The rule is this: --- unpackFoldrCString# "foo" c (unpackFoldrCString# "baz" c n) --- = unpackFoldrCString# "foobaz" c n +-- unpackFoldrCString*# "foo"# c (unpackFoldrCString*# "baz"# c n) +-- = unpackFoldrCString*# "foobaz"# c n +-- +-- See also Note [String literals in GHC] in CString.hs + +-- CString version +match_append_lit_C :: RuleFun +match_append_lit_C = match_append_lit unpackCStringFoldrIdKey -match_append_lit :: RuleFun -match_append_lit _ id_unf _ +-- CStringUTF8 version +match_append_lit_utf8 :: RuleFun +match_append_lit_utf8 = match_append_lit unpackCStringFoldrUtf8IdKey + +{-# INLINE match_append_lit #-} +match_append_lit :: Unique -> RuleFun +match_append_lit foldVariant _ id_unf _ [ Type ty1 , lit1 , c1 @@ -1395,12 +1409,13 @@ match_append_lit _ id_unf _ `App` lit2 `App` c2 `App` n) <- stripTicksTop tickishFloatable e2 - , unpk `hasKey` unpackCStringFoldrIdKey - , cheapEqExpr' tickishFloatable c1 c2 - , (c1Ticks, c1') <- stripTicksTop tickishFloatable c1 - , c2Ticks <- stripTicksTopT tickishFloatable c2 + , unpk `hasKey` foldVariant , Just (LitString s1) <- exprIsLiteral_maybe id_unf lit1 , Just (LitString s2) <- exprIsLiteral_maybe id_unf lit2 + , let freeVars = (mkInScopeSet (exprFreeVars c1 `unionVarSet` exprFreeVars c2)) + in eqExpr freeVars c1 c2 + , (c1Ticks, c1') <- stripTicksTop tickishFloatable c1 + , c2Ticks <- stripTicksTopT tickishFloatable c2 = ASSERT( ty1 `eqType` ty2 ) Just $ mkTicks strTicks $ Var unpk `App` Type ty1 @@ -1408,17 +1423,23 @@ match_append_lit _ id_unf _ `App` mkTicks (c1Ticks ++ c2Ticks) c1' `App` n -match_append_lit _ _ _ _ = Nothing +match_append_lit _ _ _ _ _ = Nothing --------------------------------------------------- -- The rule is this: -- eqString (unpackCString# (Lit s1)) (unpackCString# (Lit s2)) = s1==s2 +-- Also matches unpackCStringUtf8# match_eq_string :: RuleFun match_eq_string _ id_unf _ [Var unpk1 `App` lit1, Var unpk2 `App` lit2] - | unpk1 `hasKey` unpackCStringIdKey - , unpk2 `hasKey` unpackCStringIdKey + | unpk_key1 <- getUnique unpk1 + , unpk_key2 <- getUnique unpk2 + , unpk_key1 == unpk_key2 + -- For now we insist the literals have to agree in their encoding + -- to keep the rule simple. But we could check if the decoded strings + -- compare equal in here as well. + , unpk_key1 `elem` [unpackCStringUtf8IdKey, unpackCStringIdKey] , Just (LitString s1) <- exprIsLiteral_maybe id_unf lit1 , Just (LitString s2) <- exprIsLiteral_maybe id_unf lit2 = Just (if s1 == s2 then trueValBool else falseValBool) |