This patch remove recursion on Set_Digit and Set_Image_Unsigned
procedure.
Tested on x86_64-pc-linux-gnu, committed on trunk
gcc/ada/
* libgnat/s-imagei.adb
(Set_Digits): Rewrite the procedure to remove recursion.
(Image_Integer, Set_Image_Integer): Update assertions and remove
redundant ones.
* libgnat/s-imageu.adb
(Set_Image_Unsigned): Rewrite the procedure to remove recursion.diff --git a/gcc/ada/libgnat/s-imagei.adb b/gcc/ada/libgnat/s-imagei.adb
--- a/gcc/ada/libgnat/s-imagei.adb
+++ b/gcc/ada/libgnat/s-imagei.adb
@@ -56,8 +56,11 @@ package body System.Image_I is
if V >= 0 then
S (1) := ' ';
P := 1;
+ pragma Assert (P < S'Last);
+
else
P := 0;
+ pragma Assert (P < S'Last - 1);
end if;
Set_Image_Integer (V, S, P);
@@ -72,26 +75,31 @@ package body System.Image_I is
S : in out String;
P : in out Natural)
is
+ Nb_Digits : Natural := 0;
+ Value : Non_Positive := T;
begin
- if T <= -10 then
- Set_Digits (T / 10, S, P);
- pragma Assert (P >= (S'First - 1) and P < S'Last and
- P < Natural'Last);
- -- No check is done since, as documented in the Set_Image_Integer
- -- specification, the caller guarantees that S is long enough to
- -- hold the result.
- P := P + 1;
- S (P) := Character'Val (48 - (T rem 10));
+ pragma Assert (P >= S'First - 1 and P < S'Last);
+ -- No check is done since, as documented in the Set_Image_Integer
+ -- specification, the caller guarantees that S is long enough to
+ -- hold the result.
- else
- pragma Assert (P >= (S'First - 1) and P < S'Last and
- P < Natural'Last);
- -- No check is done since, as documented in the Set_Image_Integer
- -- specification, the caller guarantees that S is long enough to
- -- hold the result.
- P := P + 1;
- S (P) := Character'Val (48 - T);
- end if;
+ -- First we compute the number of characters needed for representing
+ -- the number.
+ loop
+ Value := Value / 10;
+ Nb_Digits := Nb_Digits + 1;
+ exit when Value = 0;
+ end loop;
+
+ Value := T;
+
+ -- We now populate digits from the end of the string to the beginning
+ for J in reverse 1 .. Nb_Digits loop
+ S (P + J) := Character'Val (48 - (Value rem 10));
+ Value := Value / 10;
+ end loop;
+
+ P := P + Nb_Digits;
end Set_Digits;
-----------------------
@@ -108,8 +116,7 @@ package body System.Image_I is
Set_Digits (-V, S, P);
else
- pragma Assert (P >= (S'First - 1) and P < S'Last and
- P < Natural'Last);
+ pragma Assert (P >= S'First - 1 and P < S'Last);
-- No check is done since, as documented in the specification,
-- the caller guarantees that S is long enough to hold the result.
P := P + 1;
diff --git a/gcc/ada/libgnat/s-imageu.adb b/gcc/ada/libgnat/s-imageu.adb
--- a/gcc/ada/libgnat/s-imageu.adb
+++ b/gcc/ada/libgnat/s-imageu.adb
@@ -56,24 +56,31 @@ package body System.Image_U is
S : in out String;
P : in out Natural)
is
+ Nb_Digits : Natural := 0;
+ Value : Uns := V;
begin
- if V >= 10 then
- Set_Image_Unsigned (V / 10, S, P);
- pragma Assert (P >= (S'First - 1) and P < S'Last and
- P < Natural'Last);
- -- No check is done since, as documented in the specification,
- -- the caller guarantees that S is long enough to hold the result.
- P := P + 1;
- S (P) := Character'Val (48 + (V rem 10));
+ pragma Assert (P >= S'First - 1 and then P < S'Last and then
+ P < Natural'Last);
+ -- No check is done since, as documented in the specification, the
+ -- caller guarantees that S is long enough to hold the result.
- else
- pragma Assert (P >= (S'First - 1) and P < S'Last and
- P < Natural'Last);
- -- No check is done since, as documented in the specification,
- -- the caller guarantees that S is long enough to hold the result.
- P := P + 1;
- S (P) := Character'Val (48 + V);
- end if;
+ -- First we compute the number of characters needed for representing
+ -- the number.
+ loop
+ Value := Value / 10;
+ Nb_Digits := Nb_Digits + 1;
+ exit when Value = 0;
+ end loop;
+
+ Value := V;
+
+ -- We now populate digits from the end of the string to the beginning
+ for J in reverse 1 .. Nb_Digits loop
+ S (P + J) := Character'Val (48 + (Value rem 10));
+ Value := Value / 10;
+ end loop;
+
+ P := P + Nb_Digits;
end Set_Image_Unsigned;
end System.Image_U;
