From ada0096b7b1d799700b6810fc5ce3ad1c2072612 Mon Sep 17 00:00:00 2001 From: hainque Date: Mon, 30 Aug 2010 13:26:10 +0000 Subject: [PATCH] * gcc-interface/decl.c (FOREIGN_FORCE_REALIGN_STACK): New macro, replacement for FORCE_PREFERRED_STACK_BOUNDARY_IN_MAIN. (gnat_to_gnu_entity) : Use it. git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@163641 138bc75d-0d04-0410-961f-82ee72b054a4 --- gcc/ada/ChangeLog | 6 ++++++ gcc/ada/gcc-interface/decl.c | 46 +++++++++++++++++--------------------------- 2 files changed, 24 insertions(+), 28 deletions(-) diff --git a/gcc/ada/ChangeLog b/gcc/ada/ChangeLog index 9fb2bf1..5b427f8 100644 --- a/gcc/ada/ChangeLog +++ b/gcc/ada/ChangeLog @@ -1,3 +1,9 @@ +2010-08-30 Olivier Hainque + + * gcc-interface/decl.c (FOREIGN_FORCE_REALIGN_STACK): New macro, + replacement for FORCE_PREFERRED_STACK_BOUNDARY_IN_MAIN. + (gnat_to_gnu_entity) : Use it. + 2010-08-21 Eric Botcazou * tracebak.c: Fix typo in comment. diff --git a/gcc/ada/gcc-interface/decl.c b/gcc/ada/gcc-interface/decl.c index 2e68eaa..75cdb84 100644 --- a/gcc/ada/gcc-interface/decl.c +++ b/gcc/ada/gcc-interface/decl.c @@ -60,27 +60,20 @@ #define Has_Stdcall_Convention(E) (0) #endif -/* Stack realignment for functions with foreign conventions is provided on a - per back-end basis now, as it is handled by the prologue expanders and not - as part of the function's body any more. It might be requested by way of a - dedicated function type attribute on the targets that support it. - - We need a way to avoid setting the attribute on the targets that don't - support it and use FORCE_PREFERRED_STACK_BOUNDARY_IN_MAIN for this purpose. - - It is defined on targets where the circuitry is available, and indicates - whether the realignment is needed for 'main'. We use this to decide for - foreign subprograms as well. - - It is not defined on targets where the circuitry is not implemented, and - we just never set the attribute in these cases. - - Whether it is defined on all targets that would need it in theory is - not entirely clear. We currently trust the base GCC settings for this - purpose. */ - -#ifndef FORCE_PREFERRED_STACK_BOUNDARY_IN_MAIN -#define FORCE_PREFERRED_STACK_BOUNDARY_IN_MAIN 0 +/* Stack realignment is necessary for functions with foreign conventions when + the ABI doesn't mandate as much as what the compiler assumes - that is, up + to PREFERRED_STACK_BOUNDARY. + + Such realignment can be requested with a dedicated function type attribute + on the targets that support it. We define FOREIGN_FORCE_REALIGN_STACK to + characterize the situations where the attribute should be set. We rely on + compiler configuration settings for 'main' to decide. */ + +#ifdef MAIN_STACK_BOUNDARY +#define FOREIGN_FORCE_REALIGN_STACK \ + (MAIN_STACK_BOUNDARY < PREFERRED_STACK_BOUNDARY) +#else +#define FOREIGN_FORCE_REALIGN_STACK 0 #endif struct incomplete @@ -4208,13 +4201,10 @@ gnat_to_gnu_entity (Entity_Id gnat_entity, tree gnu_expr, int definition) get_identifier ("stdcall"), NULL_TREE, gnat_entity); - /* If we are on a target where stack realignment is needed for 'main' - to honor GCC's implicit expectations (stack alignment greater than - what the base ABI guarantees), ensure we do the same for foreign - convention subprograms as they might be used as callbacks from code - breaking such expectations. Note that this applies to task entry - points in particular. */ - if (FORCE_PREFERRED_STACK_BOUNDARY_IN_MAIN + /* If we should request stack realignment for a foreign convention + subprogram, do so. Note that this applies to task entry points in + particular. */ + if (FOREIGN_FORCE_REALIGN_STACK && Has_Foreign_Convention (gnat_entity)) prepend_one_attribute_to (&attr_list, ATTR_MACHINE_ATTRIBUTE, -- 2.7.4