https://gcc.gnu.org/g:255d7017480fa4d7a492ccb6cfb479741fc3a820
commit r15-6144-g255d7017480fa4d7a492ccb6cfb479741fc3a820
Author: Eric Botcazou <ebotca...@adacore.com>
Date: Tue Nov 19 09:19:22 2024 +0100
ada: Minor refactoring in expansion of array aggregates
This just moves a couple of checks done in conjunction with the predicate
Aggr_Assignment_OK_For_Backend into its body and adds a couple of comments.
No functional changes.
gcc/ada/ChangeLog:
* exp_aggr.adb (Aggr_Assignment_OK_For_Backend): Add Target formal
parameter and check that it is not a bit-aligned component or slice.
Return False in CodePeer mode as well.
(Build_Array_Aggr_Code): Remove redundant tests done in conjunction
with a call to Aggr_Assignment_OK_For_Backend.
(Expand_Array_Aggregate): Likewise. Add a couple of comments and
improve formatting.
Diff:
---
gcc/ada/exp_aggr.adb | 104 +++++++++++++++++++++++++++++----------------------
1 file changed, 60 insertions(+), 44 deletions(-)
diff --git a/gcc/ada/exp_aggr.adb b/gcc/ada/exp_aggr.adb
index d0ccaa4f3ff2..37c21ac57629 100644
--- a/gcc/ada/exp_aggr.adb
+++ b/gcc/ada/exp_aggr.adb
@@ -250,8 +250,12 @@ package body Exp_Aggr is
-- Local Subprograms for Array Aggregate Expansion --
-----------------------------------------------------
- function Aggr_Assignment_OK_For_Backend (N : Node_Id) return Boolean;
- -- Returns true if an aggregate assignment can be done by the back end
+ function Aggr_Assignment_OK_For_Backend
+ (N : Node_Id;
+ Target : Node_Id := Empty) return Boolean;
+ -- Returns true if assignment of aggregate N can be done by the back end.
+ -- If Target is present, it is the left-hand side of the assignment; if it
+ -- is not, the assignment is the initialization of an object or allocator.
function Aggr_Size_OK (N : Node_Id) return Boolean;
-- Very large static aggregates present problems to the back-end, and are
@@ -371,8 +375,10 @@ package body Exp_Aggr is
-- The ultimate goal is to generate a call to a fast memset routine
-- specifically optimized for the target.
- function Aggr_Assignment_OK_For_Backend (N : Node_Id) return Boolean is
-
+ function Aggr_Assignment_OK_For_Backend
+ (N : Node_Id;
+ Target : Node_Id := Empty) return Boolean
+ is
function Is_OK_Aggregate (Aggr : Node_Id) return Boolean;
-- Return true if Aggr is suitable for back-end assignment
@@ -422,12 +428,27 @@ package body Exp_Aggr is
-- Start of processing for Aggr_Assignment_OK_For_Backend
begin
+ -- CodePeer does not support this
+
+ if CodePeer_Mode then
+ return False;
+ end if;
+
-- Back end doesn't know about <>
if Has_Default_Init_Comps (N) then
return False;
end if;
+ -- Assignments to bit-aligned components or slices are not OK
+
+ if Present (Target)
+ and then (Possible_Bit_Aligned_Component (Target)
+ or else Is_Possibly_Unaligned_Slice (Target))
+ then
+ return False;
+ end if;
+
-- Recurse as far as possible to find the innermost component type
Ctyp := Etype (N);
@@ -1922,10 +1943,7 @@ package body Exp_Aggr is
-- into an assignment statement.
if Present (Etype (N))
- and then Aggr_Assignment_OK_For_Backend (N)
- and then not Possible_Bit_Aligned_Component (Into)
- and then not Is_Possibly_Unaligned_Slice (Into)
- and then not CodePeer_Mode
+ and then Aggr_Assignment_OK_For_Backend (N, Into)
then
declare
New_Aggr : constant Node_Id := Relocate_Node (N);
@@ -6132,52 +6150,50 @@ package body Exp_Aggr is
or else (Parent_Kind in N_Aggregate | N_Extension_Aggregate
and then not Is_Container_Aggregate (Parent_Node))
- -- Allocator (see Convert_Aggr_In_Allocator)
+ -- Allocator (see Convert_Aggr_In_Allocator). Bit-packed array types
+ -- need specific processing and sliding cannot be done in place for
+ -- the time being.
or else (Nkind (Parent_Node) = N_Allocator
- and then (Aggr_Assignment_OK_For_Backend (N)
- or else Is_Limited_Type (Typ)
- or else Needs_Finalization (Typ)
- or else (not Is_Bit_Packed_Array (Typ)
- and then not
- Must_Slide
- (N,
- Designated_Type
- (Etype (Parent_Node)),
- Typ))))
-
- -- Object declaration (see Convert_Aggr_In_Object_Decl)
+ and then
+ (Aggr_Assignment_OK_For_Backend (N)
+ or else Is_Limited_Type (Typ)
+ or else Needs_Finalization (Typ)
+ or else (not Is_Bit_Packed_Array (Typ)
+ and then not
+ Must_Slide
+ (N,
+ Designated_Type (Etype (Parent_Node)),
+ Typ))))
+
+ -- Object declaration (see Convert_Aggr_In_Object_Decl). Bit-packed
+ -- array types need specific processing and sliding cannot be done
+ -- in place for the time being.
or else (Parent_Kind = N_Object_Declaration
- and then (Aggr_Assignment_OK_For_Backend (N)
- or else Is_Limited_Type (Typ)
- or else Needs_Finalization (Typ)
- or else Is_Special_Return_Object
- (Defining_Identifier (Parent_Node))
- or else (not Is_Bit_Packed_Array (Typ)
- and then not
- Must_Slide
- (N,
- Etype
- (Defining_Identifier
- (Parent_Node)),
- Typ))))
+ and then
+ (Aggr_Assignment_OK_For_Backend (N)
+ or else Is_Limited_Type (Typ)
+ or else Needs_Finalization (Typ)
+ or else Is_Special_Return_Object
+ (Defining_Identifier (Parent_Node))
+ or else (not Is_Bit_Packed_Array (Typ)
+ and then not
+ Must_Slide
+ (N,
+ Etype
+ (Defining_Identifier (Parent_Node)),
+ Typ))))
-- Safe assignment (see Convert_Aggr_In_Assignment). So far only the
-- assignments in init procs are taken into account, as well those
-- directly performed by the back end.
or else (Parent_Kind = N_Assignment_Statement
- and then (Inside_Init_Proc
- or else
- (Aggr_Assignment_OK_For_Backend (N)
- and then not
- Possible_Bit_Aligned_Component
- (Name (Parent_Node))
- and then not
- Is_Possibly_Unaligned_Slice
- (Name (Parent_Node))
- and then not CodePeer_Mode)))
+ and then
+ (Inside_Init_Proc
+ or else
+ Aggr_Assignment_OK_For_Backend (N, Name (Parent_Node))))
-- Simple return statement, which will be handled in a build-in-place
-- fashion and will ultimately be rewritten as an extended return.
