Re: [PATCH] tree-vect-transform.c: remove some "set but not used" variables

[Ira Rosen <IRAR at il dot ibm dot com>]

gcc-patches-owner@gcc.gnu.org wrote on 28/09/2008 13:51:50:

>
>
>
> I just tried to bootstrap the most recent snapshot of gcc version
> 4.4, dated 20080926, with the Intel C compiler.
>
> The Intel compiler said
>
> ../../src/gcc-4.4-20080926/gcc/tree-vect-transform.c(2366): warning
> #593: variable "bytesize" was set but never used
> ../../src/gcc-4.4-20080926/gcc/tree-vect-transform.c(2376): warning
> #593: variable "use_stmt" was set but never used
> ../../src/gcc-4.4-20080926/gcc/tree-vect-transform.c(3550): warning
> #593: variable "expr" was set but never used
> ../../src/gcc-4.4-20080926/gcc/tree-vect-transform.c(4027): warning
> #593: variable "shift_p" was set but never used
> ../../src/gcc-4.4-20080926/gcc/tree-vect-transform.c(5041): warning
> #593: variable "scalar_dest" was set but never used
> ../../src/gcc-4.4-20080926/gcc/tree-vect-transform.c(5146): warning
> #593: variable "first_stmt_vinfo" was set but never used
> ../../src/gcc-4.4-20080926/gcc/tree-vect-transform.c(6013): warning
> #593: variable "group_size" was set but never used
> ../../src/gcc-4.4-20080926/gcc/tree-vect-transform.c(6013): warning
> #593: variable "dr_chain_size" was set but never used
> ../../src/gcc-4.4-20080926/gcc/tree-vect-transform.c(8058): warning
> #593: variable "nloop" was set but never used
>
> Here is a ChangeLog entry
>
> 2009-09-28  David Binderman
>
>         * Remove some "set but not used" variables from gcc/tree-
> vect-transform.c
>
> Here is a patch to shut up the compiler. It seems to bootstrap ok.

I think that in most of the case you can remove the whole statement mot
just the assignment, like ...

>
> --- gcc/tree-vect-transform.c.sav   2008-09-28 09:04:53.000000000 +0100
> +++ gcc/tree-vect-transform.c   2008-09-28 09:09:30.000000000 +0100
> @@ -2363,7 +2363,7 @@
>    gimple epilog_stmt = NULL;
>    tree new_scalar_dest, new_dest;
>    gimple exit_phi;
> -  tree bitsize, bitpos, bytesize;
> +  tree bitsize, bitpos;
>    enum tree_code code = gimple_assign_rhs_code (stmt);
>    tree adjustment_def;
>    tree vec_initial_def, def;
> @@ -2512,7 +2512,7 @@
>    scalar_type = TREE_TYPE (scalar_dest);
>    new_scalar_dest = vect_create_destination_var (scalar_dest, NULL);
>    bitsize = TYPE_SIZE (scalar_type);
> -  bytesize = TYPE_SIZE_UNIT (scalar_type);
> +  TYPE_SIZE_UNIT (scalar_type);

... here (no need for TYPE_SIZE_UNIT (scalar_type);),

>
>
>    /* In case this is a reduction in an inner-loop while vectorizing an
outer
> @@ -3547,7 +3547,6 @@
>    int nunits_out;
>    tree vectype_out, vectype_in;
>    int ncopies, j;
> -  tree expr;
>    tree rhs_type, lhs_type;
>    tree builtin_decl;
>    enum { NARROW, NONE, WIDEN } modifier;
> @@ -3771,7 +3770,7 @@
>         }
>
>       /* Arguments are ready. Create the new vector stmt.  */
> -     expr = build2 (code1, vectype_out, vec_oprnd0, vec_oprnd1);
> +     build2 (code1, vectype_out, vec_oprnd0, vec_oprnd1);

... and here ...

>       new_stmt = gimple_build_assign_with_ops (code1, vec_dest,
vec_oprnd0,
>                       vec_oprnd1);
>       new_temp = make_ssa_name (vec_dest, new_stmt);
> @@ -4024,7 +4023,6 @@
>    VEC(tree,heap) *vec_oprnds0 = NULL, *vec_oprnds1 = NULL;
>    tree vop0, vop1;
>    unsigned int k;
> -  bool shift_p = false;
>    bool scalar_shift_arg = false;
>
>    /* Multiple types in SLP are handled by creating the appropriate
number of
> @@ -4099,8 +4097,6 @@
>    if (code == LSHIFT_EXPR || code == RSHIFT_EXPR || code == LROTATE_EXPR
>        || code == RROTATE_EXPR)
>      {
> -      shift_p = true;
> -
>        /* vector shifted by vector */
>        if (dt[1] == vect_loop_def)
>     {
> @@ -5038,12 +5034,11 @@
>    tree perm_dest, vect1, vect2, high, low;
>    gimple perm_stmt;
>    tree vectype = STMT_VINFO_VECTYPE (vinfo_for_stmt (stmt));
> -  tree scalar_dest;
>    int i;
>    unsigned int j;
>    enum tree_code high_code, low_code;
>
> -  scalar_dest = gimple_assign_lhs (stmt);
> +  gimple_assign_lhs (stmt);

... and here ...

>
>    /* Check that the operation is supported.  */
>    if (!vect_strided_store_supported (vectype))
> @@ -5143,7 +5138,6 @@
>    bool inv_p;
>    VEC(tree,heap) *vec_oprnds = NULL;
>    bool slp = (slp_node != NULL);
> -  stmt_vec_info first_stmt_vinfo;
>    unsigned int vec_num;
>
>    /* Multiple types in SLP are handled by creating the appropriate
number of
> @@ -5290,7 +5284,6 @@
>        first_stmt = stmt;
>        first_dr = dr;
>        group_size = vec_num = 1;
> -      first_stmt_vinfo = stmt_info;
>      }
>
>    if (vect_print_dump_info (REPORT_DETAILS))
> @@ -6010,7 +6003,7 @@
>    tree t = NULL_TREE, mask_vec, mask, perm_dest;
>    gimple perm_stmt = NULL;
>    stmt_vec_info next_stmt_info;
> -  int i, group_size, stride, dr_chain_size;
> +  int i, stride;
>    tree first_vec, second_vec, data_ref;
>    tree sym;
>    ssa_op_iter iter;
> @@ -6023,9 +6016,9 @@
>    mask_vec = build_vector (mask_type, t);
>    mask = vect_init_vector (stmt, mask_vec, mask_type, NULL);
>
> -  group_size = VEC_length (gimple, SLP_TREE_SCALAR_STMTS (node));
> +  VEC_length (gimple, SLP_TREE_SCALAR_STMTS (node));
>    stride = SLP_TREE_NUMBER_OF_VEC_STMTS (node) / ncopies;
> -  dr_chain_size = VEC_length (tree, dr_chain);
> +  VEC_length (tree, dr_chain);

... and here ...

Thanks,
Ira


>
>    /* Initialize the vect stmts of NODE to properly insert the generated
>       stmts later.  */
> @@ -8055,7 +8048,6 @@
>  vect_loop_versioning (loop_vec_info loop_vinfo)
>  {
>    struct loop *loop = LOOP_VINFO_LOOP (loop_vinfo);
> -  struct loop *nloop;
>    tree cond_expr = NULL_TREE;
>    gimple_seq cond_expr_stmt_list = NULL;
>    basic_block condition_bb;
> @@ -8099,7 +8091,7 @@
>    gimple_seq_add_seq (&cond_expr_stmt_list, gimplify_stmt_list);
>
>    initialize_original_copy_tables ();
> -  nloop = loop_version (loop, cond_expr, &condition_bb,
> +  loop_version (loop, cond_expr, &condition_bb,
>           prob, prob, REG_BR_PROB_BASE - prob, true);
>    free_original_copy_tables();
>
>
> Regards
>
> David Binderman
> _________________________________________________________________
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