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| author | Xavier Leroy <xavier.leroy@inria.fr> | 2016-05-17 15:37:56 +0200 |
|---|---|---|
| committer | Xavier Leroy <xavier.leroy@inria.fr> | 2016-05-17 15:37:56 +0200 |
| commit | 82f9d1f96b30106a338e77ec83b7321c2c65f929 (patch) | |
| tree | 6b8bb30473b1385f8b84fe1600f592c2bd4abed7 /backend/LTL.v | |
| parent | 672393ef623acb3e230a8019d51c87e051a7567a (diff) | |
| download | compcert-kvx-82f9d1f96b30106a338e77ec83b7321c2c65f929.tar.gz compcert-kvx-82f9d1f96b30106a338e77ec83b7321c2c65f929.zip | |
Introduce register pairs to describe calling conventions more precisely
This commit changes the loc_arguments and loc_result functions that describe calling conventions so that each argument/result can be mapped either to a single location or (in the case of a 64-bit integer) to a pair of two 32-bit locations.
In the current CompCert, all arguments/results of type Tlong are systematically split in two 32-bit halves. We will need to change this in the future to support 64-bit processors. The alternative approach implemented by this commit enables the loc_arguments and loc_result functions to describe precisely which arguments need splitting. Eventually, the remainder of CompCert should not assume anything about splitting 64-bit types in two halves.
Summary of changes:
- AST: introduce the type "rpair A" of register pairs
- Conventions1, Conventions: use it when describing calling conventions
- LTL, Linear, Mach, Asm: honor the new calling conventions when observing external calls
- Events: suppress external_call', no longer useful
- All passes from Allocation to Asmgen: adapt accordingly.
Diffstat (limited to 'backend/LTL.v')
| -rw-r--r-- | backend/LTL.v | 11 |
1 files changed, 5 insertions, 6 deletions
diff --git a/backend/LTL.v b/backend/LTL.v index bb596fa2..5f7116ae 100644 --- a/backend/LTL.v +++ b/backend/LTL.v @@ -266,9 +266,9 @@ Inductive step: state -> trace -> state -> Prop := step (Callstate s (Internal f) rs m) E0 (State s f (Vptr sp Int.zero) f.(fn_entrypoint) rs' m') | exec_function_external: forall s ef t args res rs m rs' m', - args = map rs (loc_arguments (ef_sig ef)) -> - external_call' ef ge args m t res m' -> - rs' = Locmap.setlist (map R (loc_result (ef_sig ef))) res rs -> + args = map (fun p => Locmap.getpair p rs) (loc_arguments (ef_sig ef)) -> + external_call ef ge args m t res m' -> + rs' = Locmap.setpair (loc_result (ef_sig ef)) res rs -> step (Callstate s (External ef) rs m) t (Returnstate s rs' m') | exec_return: forall f sp rs1 bb s rs m, @@ -292,9 +292,8 @@ Inductive initial_state (p: program): state -> Prop := initial_state p (Callstate nil f (Locmap.init Vundef) m0). Inductive final_state: state -> int -> Prop := - | final_state_intro: forall rs m r retcode, - loc_result signature_main = r :: nil -> - rs (R r) = Vint retcode -> + | final_state_intro: forall rs m retcode, + Locmap.getpair (map_rpair R (loc_result signature_main)) rs = Vint retcode -> final_state (Returnstate nil rs m) retcode. Definition semantics (p: program) := |