Re: [PATCH] Fix some more -Wunused-but-set* warnings in gcc/

[Richard Guenther <rguenther at suse dot de>]

On Wed, 20 Jan 2010, Jakub Jelinek wrote:

> Hi!
> 
> This patches fixes a bunch of (mostly) new -Wunused-but-set* warnings
> in the middle-end.  Can they be simply left out (which means no code change
> or at least no runtime behavior change) or are they bugs in the code that
> actually should be fixed by using those variables for something (what?)?
> 
> Bootstrapped/regtested on x86_64-linux and i686-linux.

The middle-end changes look ok.

Thanks,
Richard.

> 2010-01-19  Jakub Jelinek  <jakub@redhat.com>
> 
> 	* sel-sched.c (create_speculation_check): Remove set but not used
> 	variable twin.
> 	(try_transformation_cache): Remove set but not used variable ds.
> 	(calculate_privileged_insns): Remove set but not used variables
> 	cur_insn and min_spec_insn.
> 	(find_best_expr): Remove set but not used variable avail_n.
> 	* tree-predcom.c (base_names_in_chain_on): Remove set but not used
> 	variable e.
> 	* cgraphunit.c (assemble_thunk): Remove set but not used variable
> 	false_label.
> 	* haifa-sched.c (remove_notes): Remove set but not used variable prev.
> 	* graphite-clast-to-gimple.c (gloog): Remove set but not used variable
> 	new_scop_exit_edge.
> 
> 	* decl.c (create_array_type_for_decl): Remove set but not used
> 	variable error_msg.  Remove break stmts after return stmts.
> 
> --- gcc/sel-sched.c.jj	2010-01-14 23:34:55.000000000 +0100
> +++ gcc/sel-sched.c	2010-01-19 19:49:07.000000000 +0100
> @@ -1866,14 +1866,13 @@ create_speculation_check (expr_t c_expr,
>    if (recovery_block != NULL)
>      {
>        rtx twin_rtx;
> -      insn_t twin;
>  
>        twin_rtx = copy_rtx (PATTERN (EXPR_INSN_RTX (c_expr)));
>        twin_rtx = create_insn_rtx_from_pattern (twin_rtx, NULL_RTX);
> -      twin = sel_gen_recovery_insn_from_rtx_after (twin_rtx,
> -						   INSN_EXPR (orig_insn),
> -						   INSN_SEQNO (insn),
> -						   bb_note (recovery_block));
> +      sel_gen_recovery_insn_from_rtx_after (twin_rtx,
> +					    INSN_EXPR (orig_insn),
> +					    INSN_SEQNO (insn),
> +					    bb_note (recovery_block));
>      }
>  
>    /* If we've generated a data speculation check, make sure
> @@ -2411,10 +2410,6 @@ try_transformation_cache (expr_t expr, i
>          EXPR_TARGET_AVAILABLE (expr) = false;
>        if (pti->type == TRANS_SPECULATION)
>          {
> -          ds_t ds;
> -
> -          ds = EXPR_SPEC_DONE_DS (expr);
> -
>            EXPR_SPEC_DONE_DS (expr) = pti->ds;
>            EXPR_NEEDS_SPEC_CHECK_P (expr) |= pti->needs_check;
>          }
> @@ -4216,7 +4211,6 @@ static int
>  calculate_privileged_insns (void)
>  {
>    expr_t cur_expr, min_spec_expr = NULL;
> -  insn_t cur_insn, min_spec_insn;
>    int privileged_n = 0, i;
>  
>    for (i = 0; i < ready.n_ready; i++)
> @@ -4225,12 +4219,8 @@ calculate_privileged_insns (void)
>          continue;
>  
>        if (! min_spec_expr)
> -        {
> -          min_spec_insn = ready_element (&ready, i);
> -          min_spec_expr = find_expr_for_ready (i, true);
> -        }
> +	min_spec_expr = find_expr_for_ready (i, true);
>  
> -      cur_insn = ready_element (&ready, i);
>        cur_expr = find_expr_for_ready (i, true);
>  
>        if (EXPR_SPEC (cur_expr) > EXPR_SPEC (min_spec_expr))
> @@ -4384,7 +4374,7 @@ find_best_expr (av_set_t *av_vliw_ptr, b
>    best = fill_ready_list (av_vliw_ptr, bnds, fence, pneed_stall);
>    if (best == NULL && ready.n_ready > 0)
>      {
> -      int privileged_n, index, avail_n;
> +      int privileged_n, index;
>  
>        can_issue_more = invoke_reorder_hooks (fence);
>        if (can_issue_more > 0)
> @@ -4393,7 +4383,7 @@ find_best_expr (av_set_t *av_vliw_ptr, b
>               scheduled due to liveness restrictions on its destination register.
>               In the future, we'd like to choose once and then just probe insns
>               in the order of their priority.  */
> -          avail_n = invoke_dfa_lookahead_guard ();
> +          invoke_dfa_lookahead_guard ();
>            privileged_n = calculate_privileged_insns ();
>            can_issue_more = choose_best_insn (fence, privileged_n, &index);
>            if (can_issue_more)
> --- gcc/tree-predcom.c.jj	2009-11-25 16:47:36.000000000 +0100
> +++ gcc/tree-predcom.c	2010-01-19 19:50:49.000000000 +0100
> @@ -1879,7 +1879,6 @@ base_names_in_chain_on (struct loop *loo
>  {
>    gimple stmt, phi;
>    imm_use_iterator iter;
> -  edge e;
>  
>    SSA_NAME_VAR (name) = var;
>  
> @@ -1898,11 +1897,6 @@ base_names_in_chain_on (struct loop *loo
>        if (!phi)
>  	return;
>  
> -      if (gimple_bb (phi) == loop->header)
> -	e = loop_latch_edge (loop);
> -      else
> -	e = single_pred_edge (gimple_bb (stmt));
> -
>        name = PHI_RESULT (phi);
>        SSA_NAME_VAR (name) = var;
>      }
> --- gcc/cgraphunit.c.jj	2010-01-05 09:39:57.000000000 +0100
> +++ gcc/cgraphunit.c	2010-01-19 19:51:27.000000000 +0100
> @@ -1465,7 +1465,7 @@ assemble_thunk (struct cgraph_node *node
>  
>        if (restmp && !this_adjusting)
>          {
> -	  tree true_label = NULL_TREE, false_label = NULL_TREE;
> +	  tree true_label = NULL_TREE;
>  
>  	  if (TREE_CODE (TREE_TYPE (restmp)) == POINTER_TYPE)
>  	    {
> @@ -1479,7 +1479,6 @@ assemble_thunk (struct cgraph_node *node
>  	      else_bb = create_basic_block (NULL, (void *) 0, else_bb);
>  	      remove_edge (single_succ_edge (bb));
>  	      true_label = gimple_block_label (then_bb);
> -	      false_label = gimple_block_label (else_bb);
>  	      stmt = gimple_build_cond (NE_EXPR, restmp,
>  	      				fold_convert (TREE_TYPE (restmp),
>  						      integer_zero_node),
> --- gcc/haifa-sched.c.jj	2010-01-09 18:51:50.000000000 +0100
> +++ gcc/haifa-sched.c	2010-01-19 19:34:36.000000000 +0100
> @@ -1835,27 +1835,22 @@ concat_note_lists (rtx from_end, rtx *to
>  void
>  remove_notes (rtx head, rtx tail)
>  {
> -  rtx next_tail, prev, insn, next;
> +  rtx next_tail, insn, next;
>  
>    note_list = 0;
>    if (head == tail && !INSN_P (head))
>      return;
>  
>    next_tail = NEXT_INSN (tail);
> -  prev = PREV_INSN (head);
>    for (insn = head; insn != next_tail; insn = next)
>      {
>        next = NEXT_INSN (insn);
>        if (!NOTE_P (insn))
> -	{
> -	  prev = insn;
> -	  continue;
> -	}
> +	continue;
>  
>        switch (NOTE_KIND (insn))
>  	{
>  	case NOTE_INSN_BASIC_BLOCK:
> -	  prev = insn;
>  	  continue;
>  
>  	case NOTE_INSN_EPILOGUE_BEG:
> --- gcc/graphite-clast-to-gimple.c.jj	2010-01-14 10:44:40.000000000 +0100
> +++ gcc/graphite-clast-to-gimple.c	2010-01-19 19:33:42.000000000 +0100
> @@ -1430,7 +1430,6 @@ create_params_index (htab_t index_table,
>  bool
>  gloog (scop_p scop, htab_t bb_pbb_mapping)
>  {
> -  edge new_scop_exit_edge = NULL;
>    VEC (tree, heap) *newivs = VEC_alloc (tree, heap, 10);
>    loop_p context_loop;
>    sese region = SCOP_REGION (scop);
> @@ -1471,10 +1470,10 @@ gloog (scop_p scop, htab_t bb_pbb_mappin
>  
>    create_params_index (params_index, pc.prog);
>  
> -  new_scop_exit_edge = translate_clast (region, context_loop, pc.stmt,
> -					if_region->true_region->entry,
> -					rename_map, &newivs, newivs_index,
> -					bb_pbb_mapping, 1, params_index);
> +  translate_clast (region, context_loop, pc.stmt,
> +		   if_region->true_region->entry,
> +		   rename_map, &newivs, newivs_index,
> +		   bb_pbb_mapping, 1, params_index);
>    graphite_verify ();
>    sese_adjust_liveout_phis (region, rename_map,
>  			    if_region->region->exit->src,
> --- gcc/cp/decl.c.jj	2010-01-19 10:39:37.000000000 +0100
> +++ gcc/cp/decl.c	2010-01-19 19:52:42.000000000 +0100
> @@ -7422,15 +7422,11 @@ static tree
>  create_array_type_for_decl (tree name, tree type, tree size)
>  {
>    tree itype = NULL_TREE;
> -  const char* error_msg;
>  
>    /* If things have already gone awry, bail now.  */
>    if (type == error_mark_node || size == error_mark_node)
>      return error_mark_node;
>  
> -  /* Assume that everything will go OK.  */
> -  error_msg = NULL;
> -
>    /* If there are some types which cannot be array elements,
>       issue an error-message and return.  */
>    switch (TREE_CODE (type))
> @@ -7441,7 +7437,6 @@ create_array_type_for_decl (tree name, t
>        else
>          error ("creating array of void");
>        return error_mark_node;
> -      break;
>  
>      case FUNCTION_TYPE:
>        if (name)
> @@ -7449,7 +7444,6 @@ create_array_type_for_decl (tree name, t
>        else
>          error ("creating array of functions");
>        return error_mark_node;
> -      break;
>  
>      case REFERENCE_TYPE:
>        if (name)
> @@ -7457,7 +7451,6 @@ create_array_type_for_decl (tree name, t
>        else
>          error ("creating array of references");
>        return error_mark_node;
> -      break;
>  
>      case METHOD_TYPE:
>        if (name)
> @@ -7465,7 +7458,6 @@ create_array_type_for_decl (tree name, t
>        else
>          error ("creating array of function members");
>        return error_mark_node;
> -      break;
>  
>      default:
>        break;
> 
> 	Jakub
> 
> 

-- 
Richard Guenther <rguenther@suse.de>
Novell / SUSE Labs
SUSE LINUX Products GmbH - Nuernberg - AG Nuernberg - HRB 16746 - GF: Markus Rex