Fix PR47046: correct evolution_function_is_affine_p

"Bug 47046 - gcc.target/i386/sse4_1-movntdqa.c ICEs with -fgraphite-identity"

The problem here is that we are left with the following code to be
translated in the new representation following the transform that
Graphite has chosen:

        D.2709_14 = j_33 * i_32;
        D.2710_15 = D.2709_14 * i_32;
        D.2711_16 = D.2710_15 * sign_34;
        *D.2708_13 = D.2711_16;

In this particular case we have a nonlinear expression "i * i" for
which we have to generate code following the new graphite_iv variables.

The patch fixes the function that detects whether we are passing non
linear stuff to graphite: evolution_function_is_affine_p.  It seems
like for the moment evolution_function_is_affine_p is testing whether
an evolution function is affine only in the innermost loop, without
looking recursively at what happens in outer loops.

The chrec for this case is: {0, +, {0, +, {1, +, 2}_1}_1}_2 and we are
testing whether the evolution is affine only for the loop_2, which is
true as we have {0, +, blah}_2 with blah invariant in loop_2.

The patch adds the recursive call to evolution_function_is_affine_p.

Bootstrapped and tested on amd64-linux.

2011-07-23  Sebastian Pop  <sebastian.pop@amd.com>

	PR middle-end/47046
	* tree-chrec.h (evolution_function_is_affine_p): Recursively call
	evolution_function_is_affine_p on CHREC_RIGHT.

	* gcc.dg/graphite/id-pr47046.c: New.
---
 gcc/ChangeLog                              |    6 ++++++
 gcc/testsuite/ChangeLog                    |    5 +++++
 gcc/testsuite/gcc.dg/graphite/id-pr47046.c |   13 +++++++++++++
 gcc/tree-chrec.h                           |    4 +++-
 4 files changed, 27 insertions(+), 1 deletions(-)
 create mode 100644 gcc/testsuite/gcc.dg/graphite/id-pr47046.c

On Mon, 25 Jul 2011, Sebastian Pop wrote:

> "Bug 47046 - gcc.target/i386/sse4_1-movntdqa.c ICEs with -fgraphite-identity"
> 
> The problem here is that we are left with the following code to be
> translated in the new representation following the transform that
> Graphite has chosen:
> 
>         D.2709_14 = j_33 * i_32;
>         D.2710_15 = D.2709_14 * i_32;
>         D.2711_16 = D.2710_15 * sign_34;
>         *D.2708_13 = D.2711_16;
> 
> In this particular case we have a nonlinear expression "i * i" for
> which we have to generate code following the new graphite_iv variables.
> 
> The patch fixes the function that detects whether we are passing non
> linear stuff to graphite: evolution_function_is_affine_p.  It seems
> like for the moment evolution_function_is_affine_p is testing whether
> an evolution function is affine only in the innermost loop, without
> looking recursively at what happens in outer loops.
> 
> The chrec for this case is: {0, +, {0, +, {1, +, 2}_1}_1}_2 and we are
> testing whether the evolution is affine only for the loop_2, which is
> true as we have {0, +, blah}_2 with blah invariant in loop_2.
> 
> The patch adds the recursive call to evolution_function_is_affine_p.
> 
> Bootstrapped and tested on amd64-linux.

Ok.

Thanks,
Richard.

> 2011-07-23  Sebastian Pop  <sebastian.pop@amd.com>
> 
> 	PR middle-end/47046
> 	* tree-chrec.h (evolution_function_is_affine_p): Recursively call
> 	evolution_function_is_affine_p on CHREC_RIGHT.
> 
> 	* gcc.dg/graphite/id-pr47046.c: New.
> ---
>  gcc/ChangeLog                              |    6 ++++++
>  gcc/testsuite/ChangeLog                    |    5 +++++
>  gcc/testsuite/gcc.dg/graphite/id-pr47046.c |   13 +++++++++++++
>  gcc/tree-chrec.h                           |    4 +++-
>  4 files changed, 27 insertions(+), 1 deletions(-)
>  create mode 100644 gcc/testsuite/gcc.dg/graphite/id-pr47046.c
> 
> diff --git a/gcc/ChangeLog b/gcc/ChangeLog
> index feffc6b..2237954 100644
> --- a/gcc/ChangeLog
> +++ b/gcc/ChangeLog
> @@ -1,5 +1,11 @@
>  2011-07-23  Sebastian Pop  <sebastian.pop@amd.com>
>  
> +	PR middle-end/47046
> +	* tree-chrec.h (evolution_function_is_affine_p): Recursively call
> +	evolution_function_is_affine_p on CHREC_RIGHT.
> +
> +2011-07-23  Sebastian Pop  <sebastian.pop@amd.com>
> +
>  	PR middle-end/47594
>  	* graphite-sese-to-poly.c (scan_tree_for_params_right_scev): Sign
>  	extend constants.
> diff --git a/gcc/testsuite/ChangeLog b/gcc/testsuite/ChangeLog
> index af1211a..919484b 100644
> --- a/gcc/testsuite/ChangeLog
> +++ b/gcc/testsuite/ChangeLog
> @@ -1,5 +1,10 @@
>  2011-07-23  Sebastian Pop  <sebastian.pop@amd.com>
>  
> +	PR middle-end/47046
> +	* gcc.dg/graphite/id-pr47046.c: New.
> +
> +2011-07-23  Sebastian Pop  <sebastian.pop@amd.com>
> +
>  	PR middle-end/47594
>  	* gfortran.dg/graphite/run-id-pr47594.f90: New.
>  
> diff --git a/gcc/testsuite/gcc.dg/graphite/id-pr47046.c b/gcc/testsuite/gcc.dg/graphite/id-pr47046.c
> new file mode 100644
> index 0000000..aba38ed
> --- /dev/null
> +++ b/gcc/testsuite/gcc.dg/graphite/id-pr47046.c
> @@ -0,0 +1,13 @@
> +void
> +init_movntdqa (int *src)
> +{
> +  int i, j, sign = 1;
> +
> +  for (i = 0; i < 20; i++)
> +    for (j = 0; j < 4; j++)
> +      {
> +	src[i * 4 + j] = j * i * i * sign;
> +	sign = -sign;
> +      }
> +}
> +
> diff --git a/gcc/tree-chrec.h b/gcc/tree-chrec.h
> index b9bf71e..9b971bd 100644
> --- a/gcc/tree-chrec.h
> +++ b/gcc/tree-chrec.h
> @@ -205,7 +205,9 @@ evolution_function_is_affine_p (const_tree chrec)
>    return chrec
>      && TREE_CODE (chrec) == POLYNOMIAL_CHREC
>      && evolution_function_is_invariant_p (CHREC_RIGHT (chrec),
> -					  CHREC_VARIABLE (chrec));
> +					  CHREC_VARIABLE (chrec))
> +    && (TREE_CODE (CHREC_RIGHT (chrec)) != POLYNOMIAL_CHREC
> +	|| evolution_function_is_affine_p (CHREC_RIGHT (chrec)));
>  }
>  
>  /* Determines whether EXPR does not contains chrec expressions.  */
>