Re: [PATCH]middle-end: Handle hybrid SLP induction vectorization with early breaks.

[Richard Biener <rguenther@suse.de>]

On Tue, 19 Dec 2023, Tamar Christina wrote:

> Hi All,
> 
> While we don't support SLP for early break vectorization, we
> can land in the situation where the induction was vectorized
> through hybrid SLP.  This means when vectorizing the early
> break live operation we need to get the results of the SLP
> operation.
> 
> 
> Bootstrapped Regtested on aarch64-none-linux-gnu,
> x86_64-pc-linux-gnu and no issues.
> 
> Ok for master?

OK.

> Thanks,
> Tamar
> 
> gcc/ChangeLog:
> 
> 	* tree-vect-loop.cc (vectorizable_live_operation): Handle SLP.
> 
> gcc/testsuite/ChangeLog:
> 
> 	* gcc.dg/vect/vect-early-break_82.c: New test.
> 
> --- inline copy of patch -- 
> diff --git a/gcc/testsuite/gcc.dg/vect/vect-early-break_82.c b/gcc/testsuite/gcc.dg/vect/vect-early-break_82.c
> new file mode 100644
> index 0000000000000000000000000000000000000000..f2a6d640f9c0c381cc2af09bd824e272bcfee0b8
> --- /dev/null
> +++ b/gcc/testsuite/gcc.dg/vect/vect-early-break_82.c
> @@ -0,0 +1,27 @@
> +/* { dg-do compile } */
> +/* { dg-require-effective-target vect_early_break } */
> +/* { dg-require-effective-target vect_int } */
> +
> +/* { dg-additional-options "-Ofast" } */
> +
> +/* { dg-final { scan-tree-dump "LOOP VECTORIZED" "vect" } } */
> +
> +#include <complex.h>
> +
> +#define N 1024
> +complex double vect_a[N];
> +complex double vect_b[N];
> +  
> +complex double test4(complex double x, complex double t)
> +{
> + complex double ret = 0;
> + for (int i = 0; i < N; i++)
> + {
> +   vect_a[i] = t + i;
> +   if (vect_a[i] == x)
> +     return i;
> +   vect_a[i] += x * vect_a[i];
> +   
> + }
> + return ret;
> +}
> diff --git a/gcc/tree-vect-loop.cc b/gcc/tree-vect-loop.cc
> index 85b81d30c5ab869cb1f7323caabd9fe4648bdc50..0993d184afe068784474ac225768d9f38d76c040 100644
> --- a/gcc/tree-vect-loop.cc
> +++ b/gcc/tree-vect-loop.cc
> @@ -10856,8 +10856,8 @@ vectorizable_live_operation (vec_info *vinfo, stmt_vec_info stmt_info,
>    bitsize = vector_element_bits_tree (vectype);
>  
>    /* Get the vectorized lhs of STMT and the lane to use (counted in bits).  */
> -  tree vec_lhs, bitstart;
> -  gimple *vec_stmt;
> +  tree vec_lhs, vec_lhs0, bitstart;
> +  gimple *vec_stmt, *vec_stmt0;
>    if (slp_node)
>      {
>        gcc_assert (!loop_vinfo
> @@ -10868,6 +10868,10 @@ vectorizable_live_operation (vec_info *vinfo, stmt_vec_info stmt_info,
>        vec_lhs = SLP_TREE_VEC_DEFS (slp_node)[vec_entry];
>        vec_stmt = SSA_NAME_DEF_STMT (vec_lhs);
>  
> +      /* In case we need to early break vectorize also get the first stmt.  */
> +      vec_lhs0 = SLP_TREE_VEC_DEFS (slp_node)[0];
> +      vec_stmt0 = SSA_NAME_DEF_STMT (vec_lhs0);
> +
>        /* Get entry to use.  */
>        bitstart = bitsize_int (vec_index);
>        bitstart = int_const_binop (MULT_EXPR, bitsize, bitstart);
> @@ -10878,6 +10882,10 @@ vectorizable_live_operation (vec_info *vinfo, stmt_vec_info stmt_info,
>        vec_stmt = STMT_VINFO_VEC_STMTS (stmt_info).last ();
>        vec_lhs = gimple_get_lhs (vec_stmt);
>  
> +      /* In case we need to early break vectorize also get the first stmt.  */
> +      vec_stmt0 = STMT_VINFO_VEC_STMTS (stmt_info)[0];
> +      vec_lhs0 = gimple_get_lhs (vec_stmt0);
> +
>        /* Get the last lane in the vector.  */
>        bitstart = int_const_binop (MULT_EXPR, bitsize, bitsize_int (nunits - 1));
>      }
> @@ -10917,7 +10925,6 @@ vectorizable_live_operation (vec_info *vinfo, stmt_vec_info stmt_info,
>  		 so use ->src.  For main exit the merge block is the
>  		 destination.  */
>  	      basic_block dest = main_exit_edge ? main_e->dest : e->src;
> -	      gimple *tmp_vec_stmt = vec_stmt;
>  	      tree tmp_vec_lhs = vec_lhs;
>  	      tree tmp_bitstart = bitstart;
>  
> @@ -10928,8 +10935,7 @@ vectorizable_live_operation (vec_info *vinfo, stmt_vec_info stmt_info,
>  	      if (restart_loop
>  		  && STMT_VINFO_DEF_TYPE (stmt_info) == vect_induction_def)
>  		{
> -		  tmp_vec_stmt = STMT_VINFO_VEC_STMTS (stmt_info)[0];
> -		  tmp_vec_lhs = gimple_get_lhs (tmp_vec_stmt);
> +		  tmp_vec_lhs = vec_lhs0;
>  		  tmp_bitstart = build_zero_cst (TREE_TYPE (bitstart));
>  		}
>  
> 
> 
> 
> 
> 

-- 
Richard Biener <rguenther@suse.de>
SUSE Software Solutions Germany GmbH,
Frankenstrasse 146, 90461 Nuernberg, Germany;
GF: Ivo Totev, Andrew McDonald, Werner Knoblich; (HRB 36809, AG Nuernberg)