On Fri, 6 Oct 2017, Sebastian Pop wrote:
> On Fri, Oct 6, 2017 at 8:33 AM, Richard Biener <rguent...@suse.de> wrote:
>
> > On Fri, 6 Oct 2017, Sebastian Pop wrote:
> >
> > > On Fri, Oct 6, 2017 at 6:56 AM, Richard Biener <rguent...@suse.de>
> > wrote:
> > >
> > > >
> > > > The following fences off a few more SCEVs through scev_analyzable_p
> > given
> > > > at the end we need those pass chrec_apply when getting a rename through
> > > > SCEV.
> > > >
> > > > The SCEV in question is
> > > >
> > > > {(integer(kind=4)) {0, +, {1, +, 1}_1}_1, + 1}_2
> > > >
> > > > which fails to chrec_apply in the CHREC_LEFT part because that part
> > > > is not affine (and we're usually not replacing a IV with a constant
> > > > where chrec_apply might handle one or the other case).
> > > >
> > > > Bootstrapped and tested on x86_64-unknown-linux-gnu.
> > > >
> > > > This fixes three out of the remaining 8 codegen errors in SPEC CPU
> > 2006.
> > > >
> > > > Ok?
> > > >
> > > > Thanks,
> > > > Richard.
> > > >
> > > > 2017-10-06 Richard Biener <rguent...@suse.de>
> > > >
> > > > PR tree-optimization/82449
> > > > * sese.c (can_chrec_apply): New function.
> > > > (scev_analyzable_p): Check we can call chrec_apply on the SCEV.
> > > >
> > > > * gfortran.dg/graphite/pr82449.f: New testcase.
> >
> > >
> > > > Index: gcc/sese.c
> > > > ===================================================================
> > > > --- gcc/sese.c (revision 253477)
> > > > +++ gcc/sese.c (working copy)
> > > > @@ -421,6 +421,27 @@ invariant_in_sese_p_rec (tree t, const s
> > > > return true;
> > > > }
> > > >
> > > > +/* Check whether we can call chrec_apply on CHREC with arbitrary X and
> > > > VAR. */
> >
> > > +
> > > > +static bool
> > > > +can_chrec_apply (tree chrec)
> >
>
> Could we use scev_is_linear_expression ?
> It seems like can_chrec_apply has the same semantics.
Looks like that works.
>
> > > > +{
> > > > + if (automatically_generated_chrec_p (chrec))
> > > > + return false;
> > > > + switch (TREE_CODE (chrec))
> > > > + {
> > > > + case POLYNOMIAL_CHREC:
> > > > + if (evolution_function_is_affine_p (chrec))
> > > > + return (can_chrec_apply (CHREC_LEFT (chrec))
> > > > + && can_chrec_apply (CHREC_RIGHT (chrec)));
> > > > + return false;
> > > > + CASE_CONVERT:
> > > > + return can_chrec_apply (TREE_OPERAND (chrec, 0));
> > > > + default:;
> > > > + return tree_does_not_contain_chrecs (chrec);
> > > > + }
> > > > +}
> > > > +
> > > > /* Return true when DEF can be analyzed in REGION by the scalar
> > > > evolution analyzer. */
> > > >
> > > > @@ -449,6 +470,7 @@ scev_analyzable_p (tree def, sese_l ®
> > > > || !defined_in_sese_p (scev, region))
> > > > && (tree_does_not_contain_chrecs (scev)
> > > > || evolution_function_is_affine_p (scev))
> > > >
> > >
> > > Why isn't evolution_function_is_affine_p returning false on {0, +, {1, +,
> > > 1}_1}_1?
> > > This is quadratic.
> >
> > It returns false on that but the CHREC we ask it on is
> >
> > {(integer(kind=4)) {0, +, {1, +, 1}_1}_1, + 1}_2
> >
> > only the initial value is "quadratic".
> >
>
> Right.
> If I understand correctly, the scop is the body of loop_1,
> and we do not need to represent the quadratic evolution
> of the initial value.
Giving the following full testing now.
Richard.
2017-10-09 Richard Biener <rguent...@suse.de>
PR tree-optimization/82449
* sese.c (scev_analyzable_p): Check whether the SCEV is linear.
* gfortran.dg/graphite/pr82449.f: New testcase.
Index: gcc/sese.c
===================================================================
--- gcc/sese.c (revision 253486)
+++ gcc/sese.c (working copy)
@@ -444,14 +444,13 @@ scev_analyzable_p (tree def, sese_l ®
loop = loop_containing_stmt (SSA_NAME_DEF_STMT (def));
scev = scalar_evolution_in_region (region, loop, def);
- return !chrec_contains_undetermined (scev)
- && (TREE_CODE (scev) != SSA_NAME
- || !defined_in_sese_p (scev, region))
- && (tree_does_not_contain_chrecs (scev)
- || evolution_function_is_affine_p (scev))
- && (! loop
- || ! loop_in_sese_p (loop, region)
- || ! chrec_contains_symbols_defined_in_loop (scev, loop->num));
+ return (!chrec_contains_undetermined (scev)
+ && (TREE_CODE (scev) != SSA_NAME
+ || !defined_in_sese_p (scev, region))
+ && scev_is_linear_expression (scev)
+ && (! loop
+ || ! loop_in_sese_p (loop, region)
+ || ! chrec_contains_symbols_defined_in_loop (scev, loop->num)));
}
/* Returns the scalar evolution of T in REGION. Every variable that
Index: gcc/testsuite/gfortran.dg/graphite/pr82449.f
===================================================================
--- gcc/testsuite/gfortran.dg/graphite/pr82449.f (nonexistent)
+++ gcc/testsuite/gfortran.dg/graphite/pr82449.f (working copy)
@@ -0,0 +1,11 @@
+! { dg-do compile }
+! { dg-options "-O2 -floop-nest-optimize" }
+
+ SUBROUTINE JDFIDX(MKL,KGSH)
+ DIMENSION MKL(6,6)
+ NKL=0
+ 400 DO 40 KG = 1,KGSH
+ DO 40 LG = 1,KG
+ NKL = NKL + 1
+ 40 MKL(LG,KG) = NKL
+ END
