Ping for this Ada patch/question.
Richard Sandiford <richard.sandif...@linaro.org> writes: > Richard Biener <richard.guent...@gmail.com> writes: >>>> How does this look? Changes since v1: >>>> >>>> - Added access_fn_component_p to check for valid access function >>>> components. >>>> >>>> - Added access_fn_components_comparable_p instead of using >>>> types_compatibloe_p directly. >>>> >>>> - Added more commentary. >>>> >>>> - Added local structures to represent the sequence, so that it's >>>> more obvious which variables are temporaries and which aren't. >>>> >>>> - Added the test above to vect-alias-check-3.c. >>>> >>>> Tested on aarch64-linux-gnu and x86_64-linux-gnu. >> >> This is ok. > > Thanks. Just been retesting, and I think I must have forgotten > to include Ada last time. It turns out that the patch causes a dg-scan > regression in gnat.dg/vect17.adb, because we now think that if the > array RECORD_TYPEs *do* alias in: > > procedure Add (X, Y : aliased Sarray; R : aliased out Sarray) is > begin > for I in Sarray'Range loop > R(I) := X(I) + Y(I); > end loop; > end; > > then the dependence distance must be zero. Eric, does that hold true > for Ada? I.e. if X and R (or Y and R) alias, must it be the case that > X(I) can only alias R(I) and not for example R(I-1) or R(I+1)? Or are > the arrays allowed to overlap by an arbitrary number of indices? > > If the assumption is correct, is the patch below OK? > > Thanks, > Richard > > > 2017-06-07 Richard Sandiford <richard.sandif...@linaro.org> > > gcc/testsuite/ > * gnat.dg/vect17.ads (Sarray): Increase range to 1 .. 5. > * gnat.dg/vect17.adb (Add): Create a dependence distance of 1 > when X = R or Y = R. > > Index: gcc/testsuite/gnat.dg/vect17.ads > =================================================================== > --- gcc/testsuite/gnat.dg/vect17.ads 2015-10-14 14:58:56.000000000 +0100 > +++ gcc/testsuite/gnat.dg/vect17.ads 2017-06-07 22:10:24.796368118 +0100 > @@ -1,6 +1,6 @@ > package Vect17 is > > - type Sarray is array (1 .. 4) of Long_Float; > + type Sarray is array (1 .. 5) of Long_Float; > for Sarray'Alignment use 16; > > procedure Add (X, Y : aliased Sarray; R : aliased out Sarray); > Index: gcc/testsuite/gnat.dg/vect17.adb > =================================================================== > --- gcc/testsuite/gnat.dg/vect17.adb 2015-10-14 14:58:56.000000000 +0100 > +++ gcc/testsuite/gnat.dg/vect17.adb 2017-06-07 22:10:24.796368118 +0100 > @@ -5,8 +5,9 @@ package body Vect17 is > > procedure Add (X, Y : aliased Sarray; R : aliased out Sarray) is > begin > - for I in Sarray'Range loop > - R(I) := X(I) + Y(I); > + R(1) := X(5) + Y(5); > + for I in 1 .. 4 loop > + R(I + 1) := X(I) + Y(I); > end loop; > end; >