Fix typechecking time bug for large rationals (#15646)wip/T15646

When desugaring large overloaded literals we now avoid
computing the `Rational` value. Instead prefering to
store the significant and exponent as given where
reasonable and possible.

See Note [FractionalLit representation] for details.

1 files changed, 3 insertions, 3 deletions

diff --git a/compiler/GHC/ThToHs.hs b/compiler/GHC/ThToHs.hs
index 2a6442cab7..e78dac205d 100644
--- a/compiler/GHC/ThToHs.hs
+++ b/compiler/GHC/ThToHs.hs
@@ -1211,7 +1211,7 @@ cvtOverLit :: Lit -> CvtM (HsOverLit GhcPs)
 cvtOverLit (IntegerL i)
   = do { force i; return $ mkHsIntegral   (mkIntegralLit i) }
 cvtOverLit (RationalL r)
-  = do { force r; return $ mkHsFractional (mkFractionalLit r) }
+  = do { force r; return $ mkHsFractional (mkTHFractionalLit r) }
 cvtOverLit (StringL s)
   = do { let { s' = mkFastString s }
        ; force s'
@@ -1246,9 +1246,9 @@ cvtLit :: Lit -> CvtM (HsLit GhcPs)
 cvtLit (IntPrimL i)    = do { force i; return $ HsIntPrim NoSourceText i }
 cvtLit (WordPrimL w)   = do { force w; return $ HsWordPrim NoSourceText w }
 cvtLit (FloatPrimL f)
-  = do { force f; return $ HsFloatPrim noExtField (mkFractionalLit f) }
+  = do { force f; return $ HsFloatPrim noExtField (mkTHFractionalLit f) }
 cvtLit (DoublePrimL f)
-  = do { force f; return $ HsDoublePrim noExtField (mkFractionalLit f) }
+  = do { force f; return $ HsDoublePrim noExtField (mkTHFractionalLit f) }
 cvtLit (CharL c)       = do { force c; return $ HsChar NoSourceText c }
 cvtLit (CharPrimL c)   = do { force c; return $ HsCharPrim NoSourceText c }
 cvtLit (StringL s)     = do { let { s' = mkFastString s }