Re: [PATCH 1/4]middle-end: Revert can_special_div_by_const changes [PR108583]

[Richard Biener <rguenther@suse.de>]

On Mon, 27 Feb 2023, Tamar Christina wrote:

> Hi All,
> 
> This reverts the changes for the CAN_SPECIAL_DIV_BY_CONST hook.
> 
> Bootstrapped Regtested on aarch64-none-linux-gnu and no issues.
> 
> Ok for master?

OK (you don't need approval for such reversion).

Thanks,
Richard.

> Thanks,
> Tamar
> 
> gcc/ChangeLog:
> 
> 	PR target/108583
> 	* doc/tm.texi (TARGET_VECTORIZE_CAN_SPECIAL_DIV_BY_CONST): Remove.
> 	* doc/tm.texi.in: Likewise.
> 	* explow.cc (round_push, align_dynamic_address): Revert previous patch.
> 	* expmed.cc (expand_divmod): Likewise.
> 	* expmed.h (expand_divmod): Likewise.
> 	* expr.cc (force_operand, expand_expr_divmod): Likewise.
> 	* optabs.cc (expand_doubleword_mod, expand_doubleword_divmod): Likewise.
> 	* target.def (can_special_div_by_const): Remove.
> 	* target.h: Remove tree-core.h include
> 	* targhooks.cc (default_can_special_div_by_const): Remove.
> 	* targhooks.h (default_can_special_div_by_const): Remove.
> 	* tree-vect-generic.cc (expand_vector_operation): Remove hook.
> 	* tree-vect-patterns.cc (vect_recog_divmod_pattern): Remove hook.
> 	* tree-vect-stmts.cc (vectorizable_operation): Remove hook.
> 
> --- inline copy of patch -- 
> diff --git a/gcc/doc/tm.texi b/gcc/doc/tm.texi
> index c6c891972d1e58cd163b259ba96a599d62326865..50a8872a6695b18b9bed0d393bacf733833633db 100644
> --- a/gcc/doc/tm.texi
> +++ b/gcc/doc/tm.texi
> @@ -6137,20 +6137,6 @@ instruction pattern.  There is no need for the hook to handle these two
>  implementation approaches itself.
>  @end deftypefn
>  
> -@deftypefn {Target Hook} bool TARGET_VECTORIZE_CAN_SPECIAL_DIV_BY_CONST (enum @var{tree_code}, tree @var{vectype}, wide_int @var{constant}, rtx *@var{output}, rtx @var{in0}, rtx @var{in1})
> -This hook is used to test whether the target has a special method of
> -division of vectors of type @var{vectype} using the value @var{constant},
> -and producing a vector of type @var{vectype}.  The division
> -will then not be decomposed by the vectorizer and kept as a div.
> -
> -When the hook is being used to test whether the target supports a special
> -divide, @var{in0}, @var{in1}, and @var{output} are all null.  When the hook
> -is being used to emit a division, @var{in0} and @var{in1} are the source
> -vectors of type @var{vecttype} and @var{output} is the destination vector of
> -type @var{vectype}.
> -
> -Return true if the operation is possible, emitting instructions for it
> -if rtxes are provided and updating @var{output}.
>  @end deftypefn
>  
>  @deftypefn {Target Hook} tree TARGET_VECTORIZE_BUILTIN_VECTORIZED_FUNCTION (unsigned @var{code}, tree @var{vec_type_out}, tree @var{vec_type_in})
> diff --git a/gcc/doc/tm.texi.in b/gcc/doc/tm.texi.in
> index 613b2534149415f442163d599503efaf423b673b..3e07978a02f4e6077adae6cadc93ea4273295f1f 100644
> --- a/gcc/doc/tm.texi.in
> +++ b/gcc/doc/tm.texi.in
> @@ -4173,7 +4173,6 @@ address;  but often a machine-dependent strategy can generate better code.
>  
>  @hook TARGET_VECTORIZE_VEC_PERM_CONST
>  
> -@hook TARGET_VECTORIZE_CAN_SPECIAL_DIV_BY_CONST
>  
>  @hook TARGET_VECTORIZE_BUILTIN_VECTORIZED_FUNCTION
>  
> diff --git a/gcc/explow.cc b/gcc/explow.cc
> index 83439b32abe1b9aa4b7983eb629804f97486acbd..be9195b33323ee5597fc212f0befa016eea4573c 100644
> --- a/gcc/explow.cc
> +++ b/gcc/explow.cc
> @@ -1037,7 +1037,7 @@ round_push (rtx size)
>       TRUNC_DIV_EXPR.  */
>    size = expand_binop (Pmode, add_optab, size, alignm1_rtx,
>  		       NULL_RTX, 1, OPTAB_LIB_WIDEN);
> -  size = expand_divmod (0, TRUNC_DIV_EXPR, Pmode, NULL, NULL, size, align_rtx,
> +  size = expand_divmod (0, TRUNC_DIV_EXPR, Pmode, size, align_rtx,
>  			NULL_RTX, 1);
>    size = expand_mult (Pmode, size, align_rtx, NULL_RTX, 1);
>  
> @@ -1203,7 +1203,7 @@ align_dynamic_address (rtx target, unsigned required_align)
>  			 gen_int_mode (required_align / BITS_PER_UNIT - 1,
>  				       Pmode),
>  			 NULL_RTX, 1, OPTAB_LIB_WIDEN);
> -  target = expand_divmod (0, TRUNC_DIV_EXPR, Pmode, NULL, NULL, target,
> +  target = expand_divmod (0, TRUNC_DIV_EXPR, Pmode, target,
>  			  gen_int_mode (required_align / BITS_PER_UNIT,
>  					Pmode),
>  			  NULL_RTX, 1);
> diff --git a/gcc/expmed.h b/gcc/expmed.h
> index 0419e2dac85850889ce0bee59515e31a80c582de..4dfe635c22ee49f2dba4c53640941628068f3901 100644
> --- a/gcc/expmed.h
> +++ b/gcc/expmed.h
> @@ -710,9 +710,8 @@ extern rtx expand_shift (enum tree_code, machine_mode, rtx, poly_int64, rtx,
>  extern rtx maybe_expand_shift (enum tree_code, machine_mode, rtx, int, rtx,
>  			       int);
>  #ifdef GCC_OPTABS_H
> -extern rtx expand_divmod (int, enum tree_code, machine_mode, tree, tree,
> -			  rtx, rtx, rtx, int,
> -			  enum optab_methods = OPTAB_LIB_WIDEN);
> +extern rtx expand_divmod (int, enum tree_code, machine_mode, rtx, rtx,
> +			  rtx, int, enum optab_methods = OPTAB_LIB_WIDEN);
>  #endif
>  #endif
>  
> diff --git a/gcc/expmed.cc b/gcc/expmed.cc
> index 917360199ca56157cf3c3693b65e93cd9d8ed244..1553ea8e31eb6433025ab18a3a59c169d3b7692f 100644
> --- a/gcc/expmed.cc
> +++ b/gcc/expmed.cc
> @@ -4222,8 +4222,8 @@ expand_sdiv_pow2 (scalar_int_mode mode, rtx op0, HOST_WIDE_INT d)
>  
>  rtx
>  expand_divmod (int rem_flag, enum tree_code code, machine_mode mode,
> -	       tree treeop0, tree treeop1, rtx op0, rtx op1, rtx target,
> -	       int unsignedp, enum optab_methods methods)
> +	       rtx op0, rtx op1, rtx target, int unsignedp,
> +	       enum optab_methods methods)
>  {
>    machine_mode compute_mode;
>    rtx tquotient;
> @@ -4375,17 +4375,6 @@ expand_divmod (int rem_flag, enum tree_code code, machine_mode mode,
>  
>    last_div_const = ! rem_flag && op1_is_constant ? INTVAL (op1) : 0;
>  
> -  /* Check if the target has specific expansions for the division.  */
> -  tree cst;
> -  if (treeop0
> -      && treeop1
> -      && (cst = uniform_integer_cst_p (treeop1))
> -      && targetm.vectorize.can_special_div_by_const (code, TREE_TYPE (treeop0),
> -						     wi::to_wide (cst),
> -						     &target, op0, op1))
> -    return target;
> -
> -
>    /* Now convert to the best mode to use.  */
>    if (compute_mode != mode)
>      {
> @@ -4629,8 +4618,8 @@ expand_divmod (int rem_flag, enum tree_code code, machine_mode mode,
>  			    || (optab_handler (sdivmod_optab, int_mode)
>  				!= CODE_FOR_nothing)))
>  		      quotient = expand_divmod (0, TRUNC_DIV_EXPR,
> -						int_mode, treeop0, treeop1,
> -						op0, gen_int_mode (abs_d,
> +						int_mode, op0,
> +						gen_int_mode (abs_d,
>  							      int_mode),
>  						NULL_RTX, 0);
>  		    else
> @@ -4819,8 +4808,8 @@ expand_divmod (int rem_flag, enum tree_code code, machine_mode mode,
>  				      size - 1, NULL_RTX, 0);
>  		t3 = force_operand (gen_rtx_MINUS (int_mode, t1, nsign),
>  				    NULL_RTX);
> -		t4 = expand_divmod (0, TRUNC_DIV_EXPR, int_mode, treeop0,
> -				    treeop1, t3, op1, NULL_RTX, 0);
> +		t4 = expand_divmod (0, TRUNC_DIV_EXPR, int_mode, t3, op1,
> +				    NULL_RTX, 0);
>  		if (t4)
>  		  {
>  		    rtx t5;
> diff --git a/gcc/expr.cc b/gcc/expr.cc
> index 15be1c8db999103bb9e5fa33daa44ae06de5ace8..78d35297e755216339078d5b2280c6e277f26d72 100644
> --- a/gcc/expr.cc
> +++ b/gcc/expr.cc
> @@ -8207,17 +8207,16 @@ force_operand (rtx value, rtx target)
>  	    return expand_divmod (0,
>  				  FLOAT_MODE_P (GET_MODE (value))
>  				  ? RDIV_EXPR : TRUNC_DIV_EXPR,
> -				  GET_MODE (value), NULL, NULL, op1, op2,
> -				  target, 0);
> +				  GET_MODE (value), op1, op2, target, 0);
>  	case MOD:
> -	  return expand_divmod (1, TRUNC_MOD_EXPR, GET_MODE (value), NULL, NULL,
> -				op1, op2, target, 0);
> +	  return expand_divmod (1, TRUNC_MOD_EXPR, GET_MODE (value), op1, op2,
> +				target, 0);
>  	case UDIV:
> -	  return expand_divmod (0, TRUNC_DIV_EXPR, GET_MODE (value), NULL, NULL,
> -				op1, op2, target, 1);
> +	  return expand_divmod (0, TRUNC_DIV_EXPR, GET_MODE (value), op1, op2,
> +				target, 1);
>  	case UMOD:
> -	  return expand_divmod (1, TRUNC_MOD_EXPR, GET_MODE (value), NULL, NULL,
> -				op1, op2, target, 1);
> +	  return expand_divmod (1, TRUNC_MOD_EXPR, GET_MODE (value), op1, op2,
> +				target, 1);
>  	case ASHIFTRT:
>  	  return expand_simple_binop (GET_MODE (value), code, op1, op2,
>  				      target, 0, OPTAB_LIB_WIDEN);
> @@ -9170,13 +9169,11 @@ expand_expr_divmod (tree_code code, machine_mode mode, tree treeop0,
>        bool speed_p = optimize_insn_for_speed_p ();
>        do_pending_stack_adjust ();
>        start_sequence ();
> -      rtx uns_ret = expand_divmod (mod_p, code, mode, treeop0, treeop1,
> -				   op0, op1, target, 1);
> +      rtx uns_ret = expand_divmod (mod_p, code, mode, op0, op1, target, 1);
>        rtx_insn *uns_insns = get_insns ();
>        end_sequence ();
>        start_sequence ();
> -      rtx sgn_ret = expand_divmod (mod_p, code, mode, treeop0, treeop1,
> -				   op0, op1, target, 0);
> +      rtx sgn_ret = expand_divmod (mod_p, code, mode, op0, op1, target, 0);
>        rtx_insn *sgn_insns = get_insns ();
>        end_sequence ();
>        unsigned uns_cost = seq_cost (uns_insns, speed_p);
> @@ -9198,8 +9195,7 @@ expand_expr_divmod (tree_code code, machine_mode mode, tree treeop0,
>        emit_insn (sgn_insns);
>        return sgn_ret;
>      }
> -  return expand_divmod (mod_p, code, mode, treeop0, treeop1,
> -			op0, op1, target, unsignedp);
> +  return expand_divmod (mod_p, code, mode, op0, op1, target, unsignedp);
>  }
>  
>  rtx
> diff --git a/gcc/optabs.cc b/gcc/optabs.cc
> index cf22bfec3f5513f56d22c866231edbf322ff6945..474ccbd7915b4f144cebe0369a6e77082c1e617b 100644
> --- a/gcc/optabs.cc
> +++ b/gcc/optabs.cc
> @@ -1106,9 +1106,8 @@ expand_doubleword_mod (machine_mode mode, rtx op0, rtx op1, bool unsignedp)
>  		return NULL_RTX;
>  	    }
>  	}
> -      rtx remainder = expand_divmod (1, TRUNC_MOD_EXPR, word_mode, NULL, NULL,
> -				     sum, gen_int_mode (INTVAL (op1),
> -							word_mode),
> +      rtx remainder = expand_divmod (1, TRUNC_MOD_EXPR, word_mode, sum,
> +				     gen_int_mode (INTVAL (op1), word_mode),
>  				     NULL_RTX, 1, OPTAB_DIRECT);
>        if (remainder == NULL_RTX)
>  	return NULL_RTX;
> @@ -1211,8 +1210,8 @@ expand_doubleword_divmod (machine_mode mode, rtx op0, rtx op1, rtx *rem,
>  
>    if (op11 != const1_rtx)
>      {
> -      rtx rem2 = expand_divmod (1, TRUNC_MOD_EXPR, mode, NULL, NULL, quot1,
> -				op11, NULL_RTX, unsignedp, OPTAB_DIRECT);
> +      rtx rem2 = expand_divmod (1, TRUNC_MOD_EXPR, mode, quot1, op11,
> +				NULL_RTX, unsignedp, OPTAB_DIRECT);
>        if (rem2 == NULL_RTX)
>  	return NULL_RTX;
>  
> @@ -1226,8 +1225,8 @@ expand_doubleword_divmod (machine_mode mode, rtx op0, rtx op1, rtx *rem,
>        if (rem2 == NULL_RTX)
>  	return NULL_RTX;
>  
> -      rtx quot2 = expand_divmod (0, TRUNC_DIV_EXPR, mode, NULL, NULL, quot1,
> -				 op11, NULL_RTX, unsignedp, OPTAB_DIRECT);
> +      rtx quot2 = expand_divmod (0, TRUNC_DIV_EXPR, mode, quot1, op11,
> +				 NULL_RTX, unsignedp, OPTAB_DIRECT);
>        if (quot2 == NULL_RTX)
>  	return NULL_RTX;
>  
> diff --git a/gcc/target.def b/gcc/target.def
> index db8af0cbe81624513f114fc9bbd8be61d855f409..e0a5c7adbd962f5d08ed08d1d81afa2c2baa64a5 100644
> --- a/gcc/target.def
> +++ b/gcc/target.def
> @@ -1905,25 +1905,6 @@ implementation approaches itself.",
>  	const vec_perm_indices &sel),
>   NULL)
>  
> -DEFHOOK
> -(can_special_div_by_const,
> - "This hook is used to test whether the target has a special method of\n\
> -division of vectors of type @var{vectype} using the value @var{constant},\n\
> -and producing a vector of type @var{vectype}.  The division\n\
> -will then not be decomposed by the vectorizer and kept as a div.\n\
> -\n\
> -When the hook is being used to test whether the target supports a special\n\
> -divide, @var{in0}, @var{in1}, and @var{output} are all null.  When the hook\n\
> -is being used to emit a division, @var{in0} and @var{in1} are the source\n\
> -vectors of type @var{vecttype} and @var{output} is the destination vector of\n\
> -type @var{vectype}.\n\
> -\n\
> -Return true if the operation is possible, emitting instructions for it\n\
> -if rtxes are provided and updating @var{output}.",
> - bool, (enum tree_code, tree vectype, wide_int constant, rtx *output,
> -	rtx in0, rtx in1),
> - default_can_special_div_by_const)
> -
>  /* Return true if the target supports misaligned store/load of a
>     specific factor denoted in the third parameter.  The last parameter
>     is true if the access is defined in a packed struct.  */
> diff --git a/gcc/target.h b/gcc/target.h
> index 03fd03a52075b4836159035ec14078c0aebdd7e9..93691882757232c514fca82b99f913158c2d47b1 100644
> --- a/gcc/target.h
> +++ b/gcc/target.h
> @@ -51,7 +51,6 @@
>  #include "insn-codes.h"
>  #include "tm.h"
>  #include "hard-reg-set.h"
> -#include "tree-core.h"
>  
>  #if CHECKING_P
>  
> diff --git a/gcc/targhooks.h b/gcc/targhooks.h
> index a1df260f5483dc84f18d8f12c5202484a32d5bb7..a6a4809ca91baa5d7fad2244549317a31390f0c2 100644
> --- a/gcc/targhooks.h
> +++ b/gcc/targhooks.h
> @@ -209,8 +209,6 @@ extern void default_addr_space_diagnose_usage (addr_space_t, location_t);
>  extern rtx default_addr_space_convert (rtx, tree, tree);
>  extern unsigned int default_case_values_threshold (void);
>  extern bool default_have_conditional_execution (void);
> -extern bool default_can_special_div_by_const (enum tree_code, tree, wide_int,
> -					      rtx *, rtx, rtx);
>  
>  extern bool default_libc_has_function (enum function_class, tree);
>  extern bool default_libc_has_fast_function (int fcode);
> diff --git a/gcc/targhooks.cc b/gcc/targhooks.cc
> index fe0116521feaf32187e7bc113bf93b1805852c79..211525720a620d6f533e2da91e03877337a931e7 100644
> --- a/gcc/targhooks.cc
> +++ b/gcc/targhooks.cc
> @@ -1840,14 +1840,6 @@ default_have_conditional_execution (void)
>    return HAVE_conditional_execution;
>  }
>  
> -/* Default that no division by constant operations are special.  */
> -bool
> -default_can_special_div_by_const (enum tree_code, tree, wide_int, rtx *, rtx,
> -				  rtx)
> -{
> -  return false;
> -}
> -
>  /* By default we assume that c99 functions are present at the runtime,
>     but sincos is not.  */
>  bool
> diff --git a/gcc/tree-vect-generic.cc b/gcc/tree-vect-generic.cc
> index 166a248f4b9512d4c6fc8d760b458b7a467f7790..519a824ec727d4d4f28c14077dc3e970bed75ef6 100644
> --- a/gcc/tree-vect-generic.cc
> +++ b/gcc/tree-vect-generic.cc
> @@ -1237,17 +1237,6 @@ expand_vector_operation (gimple_stmt_iterator *gsi, tree type, tree compute_type
>  	  tree rhs2 = gimple_assign_rhs2 (assign);
>  	  tree ret;
>  
> -	  /* Check if the target was going to handle it through the special
> -	     division callback hook.  */
> -	  tree cst = uniform_integer_cst_p (rhs2);
> -	  if (cst &&
> -	      targetm.vectorize.can_special_div_by_const (code, type,
> -							  wi::to_wide (cst),
> -							  NULL,
> -							  NULL_RTX, NULL_RTX))
> -	    return NULL_TREE;
> -
> -
>  	  if (!optimize
>  	      || !VECTOR_INTEGER_TYPE_P (type)
>  	      || TREE_CODE (rhs2) != VECTOR_CST
> diff --git a/gcc/tree-vect-patterns.cc b/gcc/tree-vect-patterns.cc
> index 6934aebc69f231af24668f0a1c3d140e97f55487..1766ce277d6b88d8aa3be77e7c8abb504a10a735 100644
> --- a/gcc/tree-vect-patterns.cc
> +++ b/gcc/tree-vect-patterns.cc
> @@ -3913,14 +3913,6 @@ vect_recog_divmod_pattern (vec_info *vinfo,
>  
>        return pattern_stmt;
>      }
> -  else if ((cst = uniform_integer_cst_p (oprnd1))
> -	   && targetm.vectorize.can_special_div_by_const (rhs_code, vectype,
> -							  wi::to_wide (cst),
> -							  NULL, NULL_RTX,
> -							  NULL_RTX))
> -    {
> -      return NULL;
> -    }
>  
>    if (prec > HOST_BITS_PER_WIDE_INT
>        || integer_zerop (oprnd1))
> diff --git a/gcc/tree-vect-stmts.cc b/gcc/tree-vect-stmts.cc
> index eb4ca1f184e374d177eb43d5eb93acf6e6a8fde9..3a0fb5ad898ad42c3867f0b9564fc4e066e50081 100644
> --- a/gcc/tree-vect-stmts.cc
> +++ b/gcc/tree-vect-stmts.cc
> @@ -6263,15 +6263,6 @@ vectorizable_operation (vec_info *vinfo,
>  	}
>        target_support_p = (optab_handler (optab, vec_mode)
>  			  != CODE_FOR_nothing);
> -      tree cst;
> -      if (!target_support_p
> -	  && op1
> -	  && (cst = uniform_integer_cst_p (op1)))
> -	target_support_p
> -	  = targetm.vectorize.can_special_div_by_const (code, vectype,
> -							wi::to_wide (cst),
> -							NULL, NULL_RTX,
> -							NULL_RTX);
>      }
>  
>    bool using_emulated_vectors_p = vect_emulated_vector_p (vectype);
> 
> 
> 
> 
> 

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