https://gcc.gnu.org/g:70999668a1305571d3b5fc57168fcb060a976418
commit r15-5406-g70999668a1305571d3b5fc57168fcb060a976418
Author: Eric Botcazou <ebotca...@adacore.com>
Date: Sun Nov 10 19:20:13 2024 +0100
ada: Fix interaction of aspect Predicate and static case expressions
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.
Diff:
---
gcc/ada/exp_ch4.adb | 43 ++++++++++++++++++-------------------------
1 file changed, 18 insertions(+), 25 deletions(-)
diff --git a/gcc/ada/exp_ch4.adb b/gcc/ada/exp_ch4.adb
index 9e82b78e3b6b..5ae2d11b04c1 100644
--- a/gcc/ada/exp_ch4.adb
+++ b/gcc/ada/exp_ch4.adb
@@ -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
