OpenE2K/gcc
2
0
Fork 0
Code Issues Pull Requests Projects Releases Wiki Activity

[Ada] Use type conversion when inlining may trigger a run-time check

Browse Source 
In the frontend inlining used in GNATprove, inlining of a return statement
was using an unchecked type conversion, which could cause a necessary
run-time check on the conversion to be skipped. Now fixed.

There is no impact on compilation.

2018-05-21  Yannick Moy  <moy@adacore.com>

gcc/ada/

	* inline.adb (Expand_Inlined_Call.Process_Formals): Use a type
	conversion instead of an unchecked type conversion when inlining a
	return statement, unless type qualification is required (for character
	and string literal) or no check can result from the conversion (for
	access types).
	* opt.ads: Update comment.

From-SVN: r260458
This commit is contained in:
Yannick Moy 2018-05-21 14:51:19 +00:00 committed by Pierre-Marie de Rodat
parent 7255f3c311
commit 031936bc50
3 changed files with 33 additions and 8 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

9
gcc/ada/ChangeLog
View File

@ -1,3 +1,12 @@
2018-04-04 Yannick Moy <moy@adacore.com>
* inline.adb (Expand_Inlined_Call.Process_Formals): Use a type
conversion instead of an unchecked type conversion when inlining a
return statement, unless type qualification is required (for character
and string literal) or no check can result from the conversion (for
access types).
* opt.ads: Update comment.
2018-04-04 Hristian Kirtchev <kirtchev@adacore.com>
* sem_ch6.adb (Analyze_Subprogram_Body_Helper): Install the elaboration

30
gcc/ada/inline.adb
View File

@ -2482,26 +2482,42 @@ package body Inline is
end if;
-- Because of the presence of private types, the views of the
-- expression and the context may be different, so place an
-- unchecked conversion to the context type to avoid spurious
-- expression and the context may be different, so place
-- a type conversion to the context type to avoid spurious
-- errors, e.g. when the expression is a numeric literal and
-- the context is private. If the expression is an aggregate,
-- use a qualified expression, because an aggregate is not a
-- legal argument of a conversion. Ditto for numeric literals
-- and attributes that yield a universal type, because those
-- must be resolved to a specific type.
-- legal argument of a conversion. Ditto for numeric, character
-- and string literals, and attributes that yield a universal
-- type, because those must be resolved to a specific type.
if Nkind_In (Expression (N), N_Aggregate, N_Null)
if Nkind_In (Expression (N), N_Aggregate,
N_Null,
N_Character_Literal,
N_String_Literal)
or else Yields_Universal_Type (Expression (N))
then
Ret :=
Make_Qualified_Expression (Sloc (N),
Subtype_Mark => New_Occurrence_Of (Ret_Type, Sloc (N)),
Expression => Relocate_Node (Expression (N)));
else
-- Use an unchecked type conversion between access types, for
-- which a type conversion would not always be valid, as no
-- check may result from the conversion.
elsif Is_Access_Type (Ret_Type) then
Ret :=
Unchecked_Convert_To
(Ret_Type, Relocate_Node (Expression (N)));
-- Otherwise use a type conversion, which may trigger a check
else
Ret :=
Make_Type_Conversion (Sloc (N),
Subtype_Mark => New_Occurrence_Of (Ret_Type, Sloc (N)),
Expression => Relocate_Node (Expression (N)));
end if;
if Nkind (Targ) = N_Defining_Identifier then

2
gcc/ada/opt.ads
View File

@ -727,7 +727,7 @@ package Opt is
-- Set True to activate inlining by front-end expansion (even on GCC
-- targets, where inlining is normally handled by the back end). Set by
-- the flag -gnatN (which is now considered obsolescent, since the GCC
-- back end can do a better job of inlining than the front end these days.
-- back end can do a better job of inlining than the front end these days).
Full_Path_Name_For_Brief_Errors : Boolean := False;
-- PROJECT MANAGER