From 82f9d1f96b30106a338e77ec83b7321c2c65f929 Mon Sep 17 00:00:00 2001 From: Xavier Leroy Date: Tue, 17 May 2016 15:37:56 +0200 Subject: 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. --- backend/XTL.ml | 5 +++++ 1 file changed, 5 insertions(+) (limited to 'backend/XTL.ml') diff --git a/backend/XTL.ml b/backend/XTL.ml index 2ddbc50a..a1b7f23b 100644 --- a/backend/XTL.ml +++ b/backend/XTL.ml @@ -64,6 +64,11 @@ let vlocs ll = List.map vloc ll let vmreg mr = L(R mr) let vmregs mrl = List.map vmreg mrl +let rec vlocpairs = function + | [] -> [] + | One l :: ll -> L l :: vlocpairs ll + | Twolong(l1, l2) :: ll -> L l1 :: L l2 :: vlocpairs ll + (* Tests over variables *) let is_stack_reg = function -- cgit