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author | Xavier Leroy <xavier.leroy@inria.fr> | 2015-08-21 11:05:36 +0200 |
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committer | Xavier Leroy <xavier.leroy@inria.fr> | 2015-08-21 11:05:36 +0200 |
commit | 54f97d1988f623ba7422e13a504caeb5701ba93c (patch) | |
tree | d8dea46837352979490f4ed4516f9649fef41b98 /backend/Linear.v | |
parent | b4846ffadfa3fbb73ffa7d9c43e5218adeece8da (diff) | |
download | compcert-54f97d1988f623ba7422e13a504caeb5701ba93c.tar.gz compcert-54f97d1988f623ba7422e13a504caeb5701ba93c.zip |
Refactoring of builtins and annotations in the back-end.
Before, the back-end languages had distinct instructions
- Iannot for annotations, taking structured expressions (annot_arg)
as arguments, and producing no results'
- Ibuiltin for other builtins, using simple pseudoregs/locations/registers
as arguments and results.
This branch enriches Ibuiltin instructions so that they take structured
expressions (builtin_arg and builtin_res) as arguments and results.
This way,
- Annotations fit the general pattern of builtin functions,
so Iannot instructions are removed.
- EF_vload_global and EF_vstore_global become useless, as the
same optimization can be achieved by EF_vload/vstore taking
a structured argument of the "address of global" kind.
- Better code can be generated for builtin_memcpy between stack locations,
or volatile accesses to stack locations.
Finally, this commit also introduces a new kind of external function,
EF_debug, which is like EF_annot but produces no observable events.
It will be used later to transport debug info through the back-end,
without preventing optimizations.
Diffstat (limited to 'backend/Linear.v')
-rw-r--r-- | backend/Linear.v | 16 |
1 files changed, 5 insertions, 11 deletions
diff --git a/backend/Linear.v b/backend/Linear.v index 5d1fc0d8..8c91a809 100644 --- a/backend/Linear.v +++ b/backend/Linear.v @@ -41,8 +41,7 @@ Inductive instruction: Type := | Lstore: memory_chunk -> addressing -> list mreg -> mreg -> instruction | Lcall: signature -> mreg + ident -> instruction | Ltailcall: signature -> mreg + ident -> instruction - | Lbuiltin: external_function -> list mreg -> list mreg -> instruction - | Lannot: external_function -> list (annot_arg loc) -> instruction + | Lbuiltin: external_function -> list (builtin_arg loc) -> builtin_res mreg -> instruction | Llabel: label -> instruction | Lgoto: label -> instruction | Lcond: condition -> list mreg -> label -> instruction @@ -198,17 +197,12 @@ Inductive step: state -> trace -> state -> Prop := step (State s f (Vptr stk Int.zero) (Ltailcall sig ros :: b) rs m) E0 (Callstate s f' rs' m') | exec_Lbuiltin: - forall s f sp rs m ef args res b t vl rs' m', - external_call' ef ge (reglist rs args) m t vl m' -> - rs' = Locmap.setlist (map R res) vl (undef_regs (destroyed_by_builtin ef) rs) -> + forall s f sp rs m ef args res b vargs t vres rs' m', + eval_builtin_args ge rs sp m args vargs -> + external_call ef ge vargs m t vres m' -> + rs' = Locmap.setres res vres (undef_regs (destroyed_by_builtin ef) rs) -> step (State s f sp (Lbuiltin ef args res :: b) rs m) t (State s f sp b rs' m') - | exec_Lannot: - forall s f sp rs m ef args vl b t v m', - eval_annot_args ge rs sp m args vl -> - external_call ef ge vl m t v m' -> - step (State s f sp (Lannot ef args :: b) rs m) - t (State s f sp b rs m') | exec_Llabel: forall s f sp lbl b rs m, step (State s f sp (Llabel lbl :: b) rs m) |