diff options
Diffstat (limited to 'compiler/coreSyn')
| -rw-r--r-- | compiler/coreSyn/CoreSyn.hs | 2 | ||||
| -rw-r--r-- | compiler/coreSyn/CoreUtils.hs | 5 |
2 files changed, 7 insertions, 0 deletions
diff --git a/compiler/coreSyn/CoreSyn.hs b/compiler/coreSyn/CoreSyn.hs index 27a4c99539..68bf676fb1 100644 --- a/compiler/coreSyn/CoreSyn.hs +++ b/compiler/coreSyn/CoreSyn.hs @@ -405,6 +405,8 @@ It is important to note that top-level primitive string literals cannot be wrapped in Ticks, as is otherwise done with lifted bindings. CoreToStg expects to see just a plain (Lit (MachStr ...)) expression on the RHS of primitive string bindings; anything else and things break. CoreLint checks this invariant. +To ensure that ticks don't sneak in CoreUtils.mkTick refuses to wrap any +primitve string expression with a tick. Also see Note [Compilation plan for top-level string literals]. diff --git a/compiler/coreSyn/CoreUtils.hs b/compiler/coreSyn/CoreUtils.hs index 3d5f4bcb5a..ca67e24ca3 100644 --- a/compiler/coreSyn/CoreUtils.hs +++ b/compiler/coreSyn/CoreUtils.hs @@ -305,6 +305,11 @@ mkTick t orig_expr = mkTick' id id orig_expr -> CoreExpr mkTick' top rest expr = case expr of + -- Never tick primitive string literals. These should ultimately float up to + -- the top-level where they must be unadorned. See Note + -- [CoreSyn top-level string literals] for details. + _ | exprIsLiteralString expr -> expr + -- Cost centre ticks should never be reordered relative to each -- other. Therefore we can stop whenever two collide. Tick t2 e |