procyberian/gcc
1
0
Fork 0
Code Issues Pull requests Projects Releases Packages Wiki Activity Actions

ada: Fix interaction of aspect Predicate and static case expressions

Browse source 
The semantics of the GNAT-specific Predicate aspect should be equivalent
to those of the Static_Predicate aspect when the predicate expression is
static, but that is not correctly implemented for static case expressions.

gcc/ada/ChangeLog:

	* exp_ch4.adb (Expand_N_Case_Expression): Remove the test on
	enclosing predicate function for the return optimization.
	Rewrite it in the general case to catch all nondynamic predicates.
	(Expand_N_If_Expression): Remove the test on enclosing predicate
	function for the return optimization.
This commit is contained in:
Eric Botcazou 2024-11-10 19:20:13 +01:00 • committed by Marc Poulhiès
parent 4e23ce5070
commit 70999668a1
1 changed files with 18 additions and 25 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

43
gcc/ada/exp_ch4.adb
View file

@ -4989,17 +4989,13 @@ package body Exp_Ch4 is
------------------------------
procedure Expand_N_Case_Expression (N : Node_Id) is
Loc : constant Source_Ptr := Sloc (N);
Par : constant Node_Id := Parent (N);
Typ : constant Entity_Id := Etype (N);
In_Predicate : constant Boolean :=
Ekind (Current_Scope) in E_Function | E_Procedure
and then Is_Predicate_Function (Current_Scope);
-- Flag set when the case expression appears within a predicate
Loc : constant Source_Ptr := Sloc (N);
Par : constant Node_Id := Parent (N);
Scop : constant Entity_Id := Current_Scope;
Typ : constant Entity_Id := Etype (N);
Optimize_Return_Stmt : constant Boolean :=
Nkind (Par) = N_Simple_Return_Statement and then not In_Predicate;
Nkind (Par) = N_Simple_Return_Statement;
-- Small optimization: when the case expression appears in the context
-- of a simple return statement, expand into
@ -5012,8 +5008,7 @@ package body Exp_Ch4 is
-- end case;
-- This makes the expansion much easier when expressions are calls to
-- a BIP function. But do not perform it when the return statement is
-- within a predicate function, as this causes spurious errors.
-- build-in-place functions.
function Is_Copy_Type (Typ : Entity_Id) return Boolean;
-- Return True if we can copy objects of this type when expanding a case
@ -5081,13 +5076,17 @@ package body Exp_Ch4 is
return;
end if;
-- If the case expression is a predicate specification, and the type
-- to which it applies has a static predicate aspect, do not expand,
-- because it will be converted to the proper predicate form later.
-- If the case expression is a predicate specification, do not expand
-- because it will need to be recognized and converted to the canonical
-- predicate form later if it it happens to be static.
if In_Predicate
and then
Has_Static_Predicate_Aspect (Etype (First_Entity (Current_Scope)))
if Ekind (Scop) in E_Function | E_Procedure
and then Is_Predicate_Function (Scop)
and then Is_Entity_Name (Expression (N))
and then Entity (Expression (N)) = First_Entity (Scop)
and then (Is_Scalar_Type (Etype (Expression (N)))
or else Is_String_Type (Etype (Expression (N))))
and then not Has_Dynamic_Predicate_Aspect (Etype (Expression (N)))
then
return;
end if;
@ -5471,13 +5470,8 @@ package body Exp_Ch4 is
Par : constant Node_Id := Parent (N);
Typ : constant Entity_Id := Etype (N);
In_Predicate : constant Boolean :=
Ekind (Current_Scope) in E_Function | E_Procedure
and then Is_Predicate_Function (Current_Scope);
-- Flag set when the if expression appears within a predicate
Optimize_Return_Stmt : constant Boolean :=
Nkind (Par) = N_Simple_Return_Statement and then not In_Predicate;
Nkind (Par) = N_Simple_Return_Statement;
-- Small optimization: when the if expression appears in the context of
-- a simple return statement, expand into
@ -5488,8 +5482,7 @@ package body Exp_Ch4 is
-- end if;
-- This makes the expansion much easier when expressions are calls to
-- a BIP function. But do not perform it when the return statement is
-- within a predicate function, as this causes spurious errors.
-- build-in-place functions.
Force_Expand : constant Boolean := Is_Anonymous_Access_Actual (N);
-- Determine if we are dealing with a special case of a conditional