diff options
Diffstat (limited to 'compiler/GHC/Core/SimpleOpt.hs')
| -rw-r--r-- | compiler/GHC/Core/SimpleOpt.hs | 38 |
1 files changed, 17 insertions, 21 deletions
diff --git a/compiler/GHC/Core/SimpleOpt.hs b/compiler/GHC/Core/SimpleOpt.hs index ffec34ff17..67dc4609c3 100644 --- a/compiler/GHC/Core/SimpleOpt.hs +++ b/compiler/GHC/Core/SimpleOpt.hs @@ -48,12 +48,12 @@ import GHC.Builtin.Types import GHC.Builtin.Names import GHC.Types.Basic import GHC.Unit.Module ( Module ) +import GHC.Utils.Encoding import GHC.Utils.Outputable import GHC.Utils.Panic import GHC.Utils.Panic.Plain import GHC.Utils.Misc import GHC.Data.Maybe ( orElse ) -import GHC.Data.FastString import Data.List (mapAccumL) import qualified Data.ByteString as BS @@ -874,9 +874,8 @@ calls to unpackCString# and returns: Just (':', [Char], ['a', unpackCString# "bc"]). -We need to be careful about UTF8 strings here. ""# contains a ByteString, so -we must parse it back into a FastString to split off the first character. -That way we can treat unpackCString# and unpackCStringUtf8# in the same way. +We need to be careful about UTF8 strings here. ""# contains an encoded ByteString, so +we call utf8UnconsByteString to correctly deal with the encoding and splitting. We must also be careful about lvl = "foo"# @@ -885,6 +884,8 @@ to ensure that we see through the let-binding for 'lvl'. Hence the (exprIsLiteral_maybe .. arg) in the guard before the call to dealWithStringLiteral. +The tests for this function are in T9400. + Note [Push coercions in exprIsConApp_maybe] ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ In #13025 I found a case where we had @@ -1237,23 +1238,18 @@ dealWithStringLiteral :: Var -> BS.ByteString -> Coercion -- This is not possible with user-supplied empty literals, GHC.Core.Make.mkStringExprFS -- turns those into [] automatically, but just in case something else in GHC -- generates a string literal directly. -dealWithStringLiteral _ str co - | BS.null str - = pushCoDataCon nilDataCon [Type charTy] co - -dealWithStringLiteral fun str co - = let strFS = mkFastStringByteString str - - char = mkConApp charDataCon [mkCharLit (headFS strFS)] - charTail = BS.tail (bytesFS strFS) - - -- In singleton strings, just add [] instead of unpackCstring# ""#. - rest = if BS.null charTail - then mkConApp nilDataCon [Type charTy] - else App (Var fun) - (Lit (LitString charTail)) - - in pushCoDataCon consDataCon [Type charTy, char, rest] co +dealWithStringLiteral fun str co = + case utf8UnconsByteString str of + Nothing -> pushCoDataCon nilDataCon [Type charTy] co + Just (char, charTail) -> + let char_expr = mkConApp charDataCon [mkCharLit char] + -- In singleton strings, just add [] instead of unpackCstring# ""#. + rest = if BS.null charTail + then mkConApp nilDataCon [Type charTy] + else App (Var fun) + (Lit (LitString charTail)) + + in pushCoDataCon consDataCon [Type charTy, char_expr, rest] co {- Note [Unfolding DFuns] |