Hi Tamar,
> -----Original Message-----
> From: Gcc-patches <gcc-patches-
> bounces+kyrylo.tkachov=arm....@gcc.gnu.org> On Behalf Of Tamar
> Christina via Gcc-patches
> Sent: Friday, September 23, 2022 10:33 AM
> To: gcc-patches@gcc.gnu.org
> Cc: nd <n...@arm.com>; rguent...@suse.de
> Subject: [PATCH 1/4]middle-end Support not decomposing specific divisions
> during vectorization.
>
> Hi All,
>
> In plenty of image and video processing code it's common to modify pixel
> values
> by a widening operation and then scale them back into range by dividing by
> 255.
>
> e.g.:
>
> x = y / (2 ^ (bitsize (y)/2)-1
>
> This patch adds a new target hook can_special_div_by_const, similar to
> can_vec_perm which can be called to check if a target will handle a particular
> division in a special way in the back-end.
>
> The vectorizer will then vectorize the division using the standard tree code
> and at expansion time the hook is called again to generate the code for the
> division.
>
> Alot of the changes in the patch are to pass down the tree operands in all
> paths
> that can lead to the divmod expansion so that the target hook always has the
> type of the expression you're expanding since the types can change the
> expansion.
>
> Bootstrapped Regtested on aarch64-none-linux-gnu, x86_64-pc-linux-gnu
> and no issues.
>
> Ok for master?
>
> Thanks,
> Tamar
>
> gcc/ChangeLog:
>
> * expmed.h (expand_divmod): Pass tree operands down in addition
> to RTX.
> * expmed.cc (expand_divmod): Likewise.
> * explow.cc (round_push, align_dynamic_address): Likewise.
> * expr.cc (force_operand, expand_expr_divmod): Likewise.
> * optabs.cc (expand_doubleword_mod,
> expand_doubleword_divmod):
> Likewise.
> * target.h: Include tree-core.
> * target.def (can_special_div_by_const): New.
> * targhooks.cc (default_can_special_div_by_const): New.
> * targhooks.h (default_can_special_div_by_const): New.
> * tree-vect-generic.cc (expand_vector_operation): Use it.
> * doc/tm.texi.in: Document it.
> * doc/tm.texi: Regenerate.
> * tree-vect-patterns.cc (vect_recog_divmod_pattern): Check for
> support.
> * tree-vect-stmts.cc (vectorizable_operation): Likewise.
>
> gcc/testsuite/ChangeLog:
>
> * gcc.dg/vect/vect-div-bitmask-1.c: New test.
> * gcc.dg/vect/vect-div-bitmask-2.c: New test.
> * gcc.dg/vect/vect-div-bitmask-3.c: New test.
> * gcc.dg/vect/vect-div-bitmask.h: New file.
>
> --- inline copy of patch --
> diff --git a/gcc/doc/tm.texi b/gcc/doc/tm.texi
> index
> 92bda1a7e14a3c9ea63e151e4a49a818bf4d1bdb..adba9fe97a9b43729c5e86d
> 244a2a23e76cac097 100644
> --- a/gcc/doc/tm.texi
> +++ b/gcc/doc/tm.texi
> @@ -6112,6 +6112,22 @@ 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}, tree @var{treeop0}, tree @var{treeop1}, 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 two operands
> @code{treeop0},
> +and @code{treeop1} and producing a vector of type @var{vectype}. The
> division
> +will then not be decomposed by the and kept as a div.
I think the grammar here is wonky, can you reword this sentence please?
(I was just reading this patch to understand the optab semantics futher in the
series)
Thanks,
Kyrill
> +
> +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})
> This hook should return the decl of a function that implements the
> vectorized variant of the function with the @code{combined_fn} code
> diff --git a/gcc/doc/tm.texi.in b/gcc/doc/tm.texi.in
> index
> 112462310b134705d860153294287cfd7d4af81d..d5a745a02acdf051ea1da1b
> 04076d058c24ce093 100644
> --- a/gcc/doc/tm.texi.in
> +++ b/gcc/doc/tm.texi.in
> @@ -4164,6 +4164,8 @@ 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
>
> @hook TARGET_VECTORIZE_BUILTIN_MD_VECTORIZED_FUNCTION
> diff --git a/gcc/explow.cc b/gcc/explow.cc
> index
> ddb4d6ae3600542f8d2bb5617cdd3933a9fae6c0..568e0eb1a158c696458ae67
> 8f5e346bf34ba0036 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, size, align_rtx,
> + size = expand_divmod (0, TRUNC_DIV_EXPR, Pmode, NULL, NULL, 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, target,
> + target = expand_divmod (0, TRUNC_DIV_EXPR, Pmode, NULL, NULL, target,
> gen_int_mode (required_align / BITS_PER_UNIT,
> Pmode),
> NULL_RTX, 1);
> diff --git a/gcc/expmed.h b/gcc/expmed.h
> index
> 0b2538c4c6bd51dfdc772ef70bdf631c0bed8717..0db2986f11ff4a4b10b59501
> c6f33cb3595659b5 100644
> --- a/gcc/expmed.h
> +++ b/gcc/expmed.h
> @@ -708,8 +708,9 @@ extern rtx expand_variable_shift (enum tree_code,
> machine_mode,
> extern rtx expand_shift (enum tree_code, machine_mode, rtx, poly_int64,
> rtx,
> int);
> #ifdef GCC_OPTABS_H
> -extern rtx expand_divmod (int, enum tree_code, machine_mode, rtx, rtx,
> - rtx, int, enum optab_methods =
> OPTAB_LIB_WIDEN);
> +extern rtx expand_divmod (int, enum tree_code, machine_mode, tree, tree,
> + rtx, rtx, rtx, int,
> + enum optab_methods = OPTAB_LIB_WIDEN);
> #endif
> #endif
>
> diff --git a/gcc/expmed.cc b/gcc/expmed.cc
> index
> 8d7418be418406e72a895ecddf2dc7fdb950c76c..b64ea5ac46a9da85770a5bb
> 0990db8b97d3af414 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,
> - rtx op0, rtx op1, rtx target, int unsignedp,
> - enum optab_methods methods)
> + tree treeop0, tree treeop1, rtx op0, rtx op1, rtx target,
> + int unsignedp, enum optab_methods methods)
> {
> machine_mode compute_mode;
> rtx tquotient;
> @@ -4375,6 +4375,14 @@ 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. */
> + if (treeop0
> + && targetm.vectorize.can_special_div_by_const (code, TREE_TYPE
> (treeop0),
> + treeop0, treeop1,
> + &target, op0, op1))
> + return target;
> +
> +
> /* Now convert to the best mode to use. */
> if (compute_mode != mode)
> {
> @@ -4618,8 +4626,8 @@ 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, op0,
> - gen_int_mode (abs_d,
> + int_mode, treeop0, treeop1,
> + op0, gen_int_mode (abs_d,
> int_mode),
> NULL_RTX, 0);
> else
> @@ -4808,8 +4816,8 @@ 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, t3,
> op1,
> - NULL_RTX, 0);
> + t4 = expand_divmod (0, TRUNC_DIV_EXPR, int_mode,
> treeop0,
> + treeop1, t3, op1, NULL_RTX, 0);
> if (t4)
> {
> rtx t5;
> diff --git a/gcc/expr.cc b/gcc/expr.cc
> index
> 80bb1b8a4c5b8350fb1b8f57a99fd52e5882fcb6..b786f1d75e25f3410c0640cd
> 96a8abc055fa34d9 100644
> --- a/gcc/expr.cc
> +++ b/gcc/expr.cc
> @@ -8028,16 +8028,17 @@ force_operand (rtx value, rtx target)
> return expand_divmod (0,
> FLOAT_MODE_P (GET_MODE (value))
> ? RDIV_EXPR : TRUNC_DIV_EXPR,
> - GET_MODE (value), op1, op2, target, 0);
> + GET_MODE (value), NULL, NULL, op1, op2,
> + target, 0);
> case MOD:
> - return expand_divmod (1, TRUNC_MOD_EXPR, GET_MODE (value),
> op1, op2,
> - target, 0);
> + return expand_divmod (1, TRUNC_MOD_EXPR, GET_MODE (value),
> NULL, NULL,
> + op1, op2, target, 0);
> case UDIV:
> - return expand_divmod (0, TRUNC_DIV_EXPR, GET_MODE (value),
> op1, op2,
> - target, 1);
> + return expand_divmod (0, TRUNC_DIV_EXPR, GET_MODE (value),
> NULL, NULL,
> + op1, op2, target, 1);
> case UMOD:
> - return expand_divmod (1, TRUNC_MOD_EXPR, GET_MODE (value),
> op1, op2,
> - target, 1);
> + return expand_divmod (1, TRUNC_MOD_EXPR, GET_MODE (value),
> NULL, NULL,
> + op1, op2, target, 1);
> case ASHIFTRT:
> return expand_simple_binop (GET_MODE (value), code, op1, op2,
> target, 0, OPTAB_LIB_WIDEN);
> @@ -8990,11 +8991,13 @@ 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, op0, op1, target, 1);
> + rtx uns_ret = expand_divmod (mod_p, code, mode, treeop0, treeop1,
> + op0, op1, target, 1);
> rtx_insn *uns_insns = get_insns ();
> end_sequence ();
> start_sequence ();
> - rtx sgn_ret = expand_divmod (mod_p, code, mode, op0, op1, target, 0);
> + rtx sgn_ret = expand_divmod (mod_p, code, mode, treeop0, treeop1,
> + op0, op1, target, 0);
> rtx_insn *sgn_insns = get_insns ();
> end_sequence ();
> unsigned uns_cost = seq_cost (uns_insns, speed_p);
> @@ -9016,7 +9019,8 @@ 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, op0, op1, target, unsignedp);
> + return expand_divmod (mod_p, code, mode, treeop0, treeop1,
> + op0, op1, target, unsignedp);
> }
>
> rtx
> diff --git a/gcc/optabs.cc b/gcc/optabs.cc
> index
> 165f8d1fa22432b96967c69a58dbb7b4bf18120d..cff37ccb0dfc3dd79b97d0abf
> d872f340855dc96 100644
> --- a/gcc/optabs.cc
> +++ b/gcc/optabs.cc
> @@ -1104,8 +1104,9 @@ 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,
> sum,
> - gen_int_mode (INTVAL (op1),
> word_mode),
> + rtx remainder = expand_divmod (1, TRUNC_MOD_EXPR, word_mode,
> NULL, NULL,
> + sum, gen_int_mode (INTVAL (op1),
> + word_mode),
> NULL_RTX, 1, OPTAB_DIRECT);
> if (remainder == NULL_RTX)
> return NULL_RTX;
> @@ -1208,8 +1209,8 @@ 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, quot1, op11,
> - NULL_RTX, unsignedp, OPTAB_DIRECT);
> + rtx rem2 = expand_divmod (1, TRUNC_MOD_EXPR, mode, NULL, NULL,
> quot1,
> + op11, NULL_RTX, unsignedp, OPTAB_DIRECT);
> if (rem2 == NULL_RTX)
> return NULL_RTX;
>
> @@ -1223,8 +1224,8 @@ 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, quot1, op11,
> - NULL_RTX, unsignedp, OPTAB_DIRECT);
> + rtx quot2 = expand_divmod (0, TRUNC_DIV_EXPR, mode, NULL, NULL,
> 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
> 2a7fa68f83dd15dcdd2c332e8431e6142ec7d305..92ebd2af18fe8abb6ed95b0
> 7081cdd70113db9b1 100644
> --- a/gcc/target.def
> +++ b/gcc/target.def
> @@ -1902,6 +1902,25 @@ 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 two operands
> @code{treeop0},\n\
> +and @code{treeop1} and producing a vector of type @var{vectype}. The
> division\n\
> +will then not be decomposed by the 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, tree treeop0, tree treeop1, 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
> d6fa6931499d15edff3e5af3e429540d001c7058..c836036ac7fa7910d62bd3da
> 56f39c061f68b665 100644
> --- a/gcc/target.h
> +++ b/gcc/target.h
> @@ -51,6 +51,7 @@
> #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
> ecce55ebe797cedc940620e8d89816973a045d49..42451a3e22e86fee9da2f56e
> 2640d63f936b336d 100644
> --- a/gcc/targhooks.h
> +++ b/gcc/targhooks.h
> @@ -207,6 +207,8 @@ 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, tree,
> tree,
> + 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
> b15ae19bcb60c59ae8112e67b5f06a241a9bdbf1..8206533382611a7640efba2
> 41279936ced41ee95 100644
> --- a/gcc/targhooks.cc
> +++ b/gcc/targhooks.cc
> @@ -1807,6 +1807,14 @@ 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, tree, tree, 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/testsuite/gcc.dg/vect/vect-div-bitmask-1.c
> b/gcc/testsuite/gcc.dg/vect/vect-div-bitmask-1.c
> new file mode 100644
> index
> 0000000000000000000000000000000000000000..472cd710534bc8aa9b1b491
> 6f3d7b4d5b64a19b9
> --- /dev/null
> +++ b/gcc/testsuite/gcc.dg/vect/vect-div-bitmask-1.c
> @@ -0,0 +1,25 @@
> +/* { dg-require-effective-target vect_int } */
> +
> +#include <stdint.h>
> +#include "tree-vect.h"
> +
> +#define N 50
> +#define TYPE uint8_t
> +
> +__attribute__((noipa, noinline, optimize("O1")))
> +void fun1(TYPE* restrict pixel, TYPE level, int n)
> +{
> + for (int i = 0; i < n; i+=1)
> + pixel[i] = (pixel[i] * level) / 0xff;
> +}
> +
> +__attribute__((noipa, noinline, optimize("O3")))
> +void fun2(TYPE* restrict pixel, TYPE level, int n)
> +{
> + for (int i = 0; i < n; i+=1)
> + pixel[i] = (pixel[i] * level) / 0xff;
> +}
> +
> +#include "vect-div-bitmask.h"
> +
> +/* { dg-final { scan-tree-dump-not "vect_recog_divmod_pattern: detected"
> "vect" { target aarch64*-*-* } } } */
> diff --git a/gcc/testsuite/gcc.dg/vect/vect-div-bitmask-2.c
> b/gcc/testsuite/gcc.dg/vect/vect-div-bitmask-2.c
> new file mode 100644
> index
> 0000000000000000000000000000000000000000..e904a71885b2e8487593a2c
> d3db75b3e4112e2cc
> --- /dev/null
> +++ b/gcc/testsuite/gcc.dg/vect/vect-div-bitmask-2.c
> @@ -0,0 +1,25 @@
> +/* { dg-require-effective-target vect_int } */
> +
> +#include <stdint.h>
> +#include "tree-vect.h"
> +
> +#define N 50
> +#define TYPE uint16_t
> +
> +__attribute__((noipa, noinline, optimize("O1")))
> +void fun1(TYPE* restrict pixel, TYPE level, int n)
> +{
> + for (int i = 0; i < n; i+=1)
> + pixel[i] = (pixel[i] * level) / 0xffffU;
> +}
> +
> +__attribute__((noipa, noinline, optimize("O3")))
> +void fun2(TYPE* restrict pixel, TYPE level, int n)
> +{
> + for (int i = 0; i < n; i+=1)
> + pixel[i] = (pixel[i] * level) / 0xffffU;
> +}
> +
> +#include "vect-div-bitmask.h"
> +
> +/* { dg-final { scan-tree-dump-not "vect_recog_divmod_pattern: detected"
> "vect" { target aarch64*-*-* } } } */
> diff --git a/gcc/testsuite/gcc.dg/vect/vect-div-bitmask-3.c
> b/gcc/testsuite/gcc.dg/vect/vect-div-bitmask-3.c
> new file mode 100644
> index
> 0000000000000000000000000000000000000000..a1418ebbf5ea8731ed4e3e7
> 20157701d9d1cf852
> --- /dev/null
> +++ b/gcc/testsuite/gcc.dg/vect/vect-div-bitmask-3.c
> @@ -0,0 +1,26 @@
> +/* { dg-require-effective-target vect_int } */
> +/* { dg-additional-options "-fno-vect-cost-model" { target aarch64*-*-* } }
> */
> +
> +#include <stdint.h>
> +#include "tree-vect.h"
> +
> +#define N 50
> +#define TYPE uint32_t
> +
> +__attribute__((noipa, noinline, optimize("O1")))
> +void fun1(TYPE* restrict pixel, TYPE level, int n)
> +{
> + for (int i = 0; i < n; i+=1)
> + pixel[i] = (pixel[i] * (uint64_t)level) / 0xffffffffUL;
> +}
> +
> +__attribute__((noipa, noinline, optimize("O3")))
> +void fun2(TYPE* restrict pixel, TYPE level, int n)
> +{
> + for (int i = 0; i < n; i+=1)
> + pixel[i] = (pixel[i] * (uint64_t)level) / 0xffffffffUL;
> +}
> +
> +#include "vect-div-bitmask.h"
> +
> +/* { dg-final { scan-tree-dump-not "vect_recog_divmod_pattern: detected"
> "vect" { target aarch64*-*-* } } } */
> diff --git a/gcc/testsuite/gcc.dg/vect/vect-div-bitmask.h
> b/gcc/testsuite/gcc.dg/vect/vect-div-bitmask.h
> new file mode 100644
> index
> 0000000000000000000000000000000000000000..29a16739aa4b706616367bf
> d1832f28ebd07993e
> --- /dev/null
> +++ b/gcc/testsuite/gcc.dg/vect/vect-div-bitmask.h
> @@ -0,0 +1,43 @@
> +#include <stdio.h>
> +
> +#ifndef N
> +#define N 65
> +#endif
> +
> +#ifndef TYPE
> +#define TYPE uint32_t
> +#endif
> +
> +#ifndef DEBUG
> +#define DEBUG 0
> +#endif
> +
> +#define BASE ((TYPE) -1 < 0 ? -126 : 4)
> +
> +int main ()
> +{
> + TYPE a[N];
> + TYPE b[N];
> +
> + for (int i = 0; i < N; ++i)
> + {
> + a[i] = BASE + i * 13;
> + b[i] = BASE + i * 13;
> + if (DEBUG)
> + printf ("%d: 0x%x\n", i, a[i]);
> + }
> +
> + fun1 (a, N / 2, N);
> + fun2 (b, N / 2, N);
> +
> + for (int i = 0; i < N; ++i)
> + {
> + if (DEBUG)
> + printf ("%d = 0x%x == 0x%x\n", i, a[i], b[i]);
> +
> + if (a[i] != b[i])
> + __builtin_abort ();
> + }
> + return 0;
> +}
> +
> diff --git a/gcc/tree-vect-generic.cc b/gcc/tree-vect-generic.cc
> index
> 350129555a0c71c0896c4f1003163f3b3557c11b..ebee5e24b186915ebcb3a817
> c9a12046b6ec94f3 100644
> --- a/gcc/tree-vect-generic.cc
> +++ b/gcc/tree-vect-generic.cc
> @@ -1237,6 +1237,14 @@ 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. */
> + if (targetm.vectorize.can_special_div_by_const (code, type, rhs1,
> + rhs2, 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
> 09574bb1a2696b3438a4ce9f09f74b42e784aca0..607acdf95eb30335d8bc0e85
> af0b1bfea10fe443 100644
> --- a/gcc/tree-vect-patterns.cc
> +++ b/gcc/tree-vect-patterns.cc
> @@ -3596,6 +3596,12 @@ vect_recog_divmod_pattern (vec_info *vinfo,
>
> return pattern_stmt;
> }
> + else if (targetm.vectorize.can_special_div_by_const (rhs_code, vectype,
> + oprnd0, oprnd1, 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
> c9dab217f059f17e91e9a7582523e627d7a45b66..6d05c48a7339de094d7288b
> d68e0e1c1e93faafe 100644
> --- a/gcc/tree-vect-stmts.cc
> +++ b/gcc/tree-vect-stmts.cc
> @@ -6260,6 +6260,11 @@ vectorizable_operation (vec_info *vinfo,
> }
> target_support_p = (optab_handler (optab, vec_mode)
> != CODE_FOR_nothing);
> + if (!target_support_p)
> + target_support_p
> + = targetm.vectorize.can_special_div_by_const (code, vectype,
> + op0, op1, NULL,
> + NULL_RTX,
> NULL_RTX);
> }
>
> bool using_emulated_vectors_p = vect_emulated_vector_p (vectype);
>
>
>
>
> --
