A code snippet using Strict State Monad

state.dump-asm

_Main_mainzuzdszdwa_info:
Lc2q2:
        addq $40,%r12
        cmpq 144(%r13),%r12
        ja Lc2q7
        cmpq $100,%r14
        jg Lc2qb
        movq %rsi,%rax
        addq %r14,%rax
        incq %r14 
        movq %rax,%rsi
        addq $-40,%r12
        jmp _Main_mainzuzdszdwa_info

state.dump-simpl

Main.main_$s$wa =
  \ (sc_s2fe :: GHC.Prim.Int#)
    (sc1_s2ff :: GHC.Prim.Int#)
    (sc2_s2fg :: GHC.Types.Int) ->
    case GHC.Prim.># sc_s2fe 100 of _ {
      GHC.Types.False ->
        Main.main_$s$wa
          (GHC.Prim.+# sc_s2fe 1) (GHC.Prim.+# sc1_s2ff sc_s2fe) sc2_s2fg;
      GHC.Types.True ->
        (# GHC.Tuple.(), Main.MyState (GHC.Types.I# sc1_s2ff) sc2_s2fg #)
    }
end Rec }

state.hs

{-# LANGUAGE BangPatterns #-}

module Main (main) where

import Control.Monad.State.Strict

data MyState = MyState !Int !Int deriving Show

main :: IO ()
main = print $ execState (f 1) (MyState 0 0)

f :: Int -> State MyState ()
f n | n > 100   = return ()
    | otherwise = modify' (\(MyState s t) -> MyState (s + n) t) >> f (n + 1)

modify' :: (MonadState s m) => (s -> s) -> m ()
modify' f = do
  s <- get 
  put $! f s