https://gcc.gnu.org/g:c3db7e37a74680b98bcd8c582f0ef3f8778b4dde
commit r15-5242-gc3db7e37a74680b98bcd8c582f0ef3f8778b4dde
Author: Eric Botcazou <ebotca...@adacore.com>
Date: Thu Oct 31 09:12:48 2024 +0100
ada: Fix outdated description in System.Arith_* units
Mainly System.Arith_Double, which has left-overs from its original version.
gcc/ada/ChangeLog:
* libgnat/s-aridou.ads (Add_With_Ovflo_Check): Adjust description.
(Subtract_With_Ovflo_Check): Likewise.
(Multiply_With_Ovflo_Check): Likewise.
(Scaled_Divide): Likewise.
(Double_Divide): Likewise.
* libgnat/s-arit64.ads (Multiply_With_Ovflo_Check64): Likewise.
* libgnat/s-arit128.ads (Multiply_With_Ovflo_Check128): Likewise.
Diff:
---
gcc/ada/libgnat/s-aridou.ads | 36 ++++++++++++++++++------------------
gcc/ada/libgnat/s-arit128.ads | 2 +-
gcc/ada/libgnat/s-arit64.ads | 2 +-
3 files changed, 20 insertions(+), 20 deletions(-)
diff --git a/gcc/ada/libgnat/s-aridou.ads b/gcc/ada/libgnat/s-aridou.ads
index f1275adbd57a..4618295e0ac0 100644
--- a/gcc/ada/libgnat/s-aridou.ads
+++ b/gcc/ada/libgnat/s-aridou.ads
@@ -100,8 +100,8 @@ is
with
Pre => In_Double_Int_Range (Big (X) + Big (Y)),
Post => Add_With_Ovflo_Check'Result = X + Y;
- -- Raises Constraint_Error if sum of operands overflows 64 bits,
- -- otherwise returns the 64-bit signed integer sum.
+ -- Raises Constraint_Error if sum of operands overflows Double_Int,
+ -- otherwise returns this sum of operands as Double_Int.
--
-- The sum of ``X`` and ``Y`` is first computed using wrap-around
-- semantics.
@@ -118,8 +118,8 @@ is
with
Pre => In_Double_Int_Range (Big (X) - Big (Y)),
Post => Subtract_With_Ovflo_Check'Result = X - Y;
- -- Raises Constraint_Error if difference of operands overflows 64
- -- bits, otherwise returns the 64-bit signed integer difference.
+ -- Raises Constraint_Error if difference of operands overflows Double_Int,
+ -- otherwise returns this difference of operands as Double_Int.
--
-- The logic of the implementation is reversed from *Add_With_Ovflo_Check*:
-- if ``X`` and ``Y`` have the same sign, no overflow is checked, otherwise
@@ -131,12 +131,12 @@ is
Pre => In_Double_Int_Range (Big (X) * Big (Y)),
Post => Multiply_With_Ovflo_Check'Result = X * Y;
pragma Convention (C, Multiply_With_Ovflo_Check);
- -- Raises Constraint_Error if product of operands overflows 64
- -- bits, otherwise returns the 64-bit signed integer product.
- -- GIGI may also call this routine directly.
+ -- Raises Constraint_Error if product of operands overflows Double_Int,
+ -- otherwise returns this product of operands as Double_Int. The code
+ -- generator may also generate direct calls to this routine.
--
- -- The multiplication is done using pencil and paper algorithm using base
- -- 2**32. The multiplication is done on unsigned values, then the correct
+ -- The multiplication is done using pencil and paper algorithm applied to
+ -- Single_Uns, that is to say done on unsigned values, then the correct
-- signed value is returned. Overflow check is performed by looking at
-- higher digits.
@@ -186,13 +186,13 @@ is
-- quotient. The remainder ``R`` is not affected by the setting of the
-- ``Round`` flag.
--
- -- The multiplication is done using pencil and paper algorithm using base
- -- 2**32. The multiplication is done on unsigned values. The result is a
- -- 128 bit value.
+ -- The multiplication is done using pencil and paper algorithm applied to
+ -- Single_Uns, that is to say done on unsigned values. The result is a
+ -- pair of Double_Uns values.
--
-- The overflow is detected on the intermediate value.
--
- -- If Z is a 32 bit value, the division is done using pencil and paper
+ -- If Z is a Single_Uns value, the division is done using pencil and paper
-- algorithm.
--
-- Otherwise, the division is performed using the algorithm D from section
@@ -232,14 +232,14 @@ is
--
-- Division by 0 is first detected.
--
- -- The intermediate value ``Y`` * ``Z`` is then computed on 128 bits. The
- -- multiplication is done on unsigned values.
+ -- The intermediate value ``Y`` * ``Z`` is then computed as a pair of
+ -- Double_Uns value. that is to say done on unsigned values.
--
- -- If the high 64 bits of the intermediate value is not 0, then 0 is
+ -- If the high Double_Uns of the intermediate value is not 0, then 0 is
-- returned. The overflow case of the largest negative number divided by
-- -1 is detected here.
--
- -- 64-bit division is then performed, the result is rounded, its sign is
- -- corrected, and then returned.
+ -- Double_Uns division is then performed, the result is rounded, its sign
+ -- is corrected, and then returned.
end System.Arith_Double;
diff --git a/gcc/ada/libgnat/s-arit128.ads b/gcc/ada/libgnat/s-arit128.ads
index 3eb170f42b3d..275b30fca9f4 100644
--- a/gcc/ada/libgnat/s-arit128.ads
+++ b/gcc/ada/libgnat/s-arit128.ads
@@ -96,7 +96,7 @@ is
pragma Export (C, Multiply_With_Ovflo_Check128, "__gnat_mulv128");
-- Raises Constraint_Error if product of operands overflows 128
-- bits, otherwise returns the 128-bit signed integer product.
- -- Gigi may also call this routine directly.
+ -- The code generator may also generate direct calls to this routine.
function Same_Sign (X, Y : Big_Integer) return Boolean is
(X = Big (Int128'(0))
diff --git a/gcc/ada/libgnat/s-arit64.ads b/gcc/ada/libgnat/s-arit64.ads
index cbf0af5fc25d..efc1f5f877fe 100644
--- a/gcc/ada/libgnat/s-arit64.ads
+++ b/gcc/ada/libgnat/s-arit64.ads
@@ -112,7 +112,7 @@ is
pragma Export (C, Multiply_With_Ovflo_Check64, "__gnat_mulv64");
-- Raises Constraint_Error if product of operands overflows 64
-- bits, otherwise returns the 64-bit signed integer product.
- -- GIGI may also call this routine directly.
+ -- The code generator may also generate direct calls to this routine.
--
-- The multiplication is done using pencil and paper algorithm using base
-- 2**32. The multiplication is done on unsigned values, then the correct
