On Wed, 1 Jun 2022 at 14:12, Richard Sandiford wrote: > > Prathamesh Kulkarni writes: > > On Thu, 12 May 2022 at 16:15, Richard Sandiford > > wrote: > >> > >> Prathamesh Kulkarni writes: > >> > On Wed, 11 May 2022 at 12:44, Richard Sandiford > >> > wrote: > >> >> > >> >> Prathamesh Kulkarni writes: > >> >> > On Fri, 6 May 2022 at 16:00, Richard Sandiford > >> >> > wrote: > >> >> >> > >> >> >> Prathamesh Kulkarni writes: > >> >> >> > diff --git a/gcc/config/aarch64/aarch64-sve-builtins-base.cc b/gcc/config/aarch64/aarch64-sve-builtins-base.cc > >> >> >> > index c24c0548724..1ef4ea2087b 100644 > >> >> >> > --- a/gcc/config/aarch64/aarch64-sve-builtins-base.cc > >> >> >> > +++ b/gcc/config/aarch64/aarch64-sve-builtins-base.cc > >> >> >> > @@ -44,6 +44,14 @@ > >> >> >> > #include "aarch64-sve-builtins-shapes.h" > >> >> >> > #include "aarch64-sve-builtins-base.h" > >> >> >> > #include "aarch64-sve-builtins-functions.h" > >> >> >> > +#include "aarch64-builtins.h" > >> >> >> > +#include "gimple-ssa.h" > >> >> >> > +#include "tree-phinodes.h" > >> >> >> > +#include "tree-ssa-operands.h" > >> >> >> > +#include "ssa-iterators.h" > >> >> >> > +#include "stringpool.h" > >> >> >> > +#include "value-range.h" > >> >> >> > +#include "tree-ssanames.h" > >> >> >> > >> >> >> Minor, but: I think the preferred approach is to include "ssa.h" > >> >> >> rather than include some of these headers directly. > >> >> >> > >> >> >> > > >> >> >> > using namespace aarch64_sve; > >> >> >> > > >> >> >> > @@ -1207,6 +1215,56 @@ public: > >> >> >> > insn_code icode = code_for_aarch64_sve_ld1rq (e.vector_mode (0)); > >> >> >> > return e.use_contiguous_load_insn (icode); > >> >> >> > } > >> >> >> > + > >> >> >> > + gimple * > >> >> >> > + fold (gimple_folder &f) const OVERRIDE > >> >> >> > + { > >> >> >> > + tree arg0 = gimple_call_arg (f.call, 0); > >> >> >> > + tree arg1 = gimple_call_arg (f.call, 1); > >> >> >> > + > >> >> >> > + /* Transform: > >> >> >> > + lhs = svld1rq ({-1, -1, ... }, arg1) > >> >> >> > + into: > >> >> >> > + tmp = mem_ref [(int * {ref-all}) arg1] > >> >> >> > + lhs = vec_perm_expr. > >> >> >> > + on little endian target. */ > >> >> >> > + > >> >> >> > + if (!BYTES_BIG_ENDIAN > >> >> >> > + && integer_all_onesp (arg0)) > >> >> >> > + { > >> >> >> > + tree lhs = gimple_call_lhs (f.call); > >> >> >> > + auto simd_type = aarch64_get_simd_info_for_type (Int32x4_t); > >> >> >> > >> >> >> Does this work for other element sizes? I would have expected it > >> >> >> to be the (128-bit) Advanced SIMD vector associated with the same > >> >> >> element type as the SVE vector. > >> >> >> > >> >> >> The testcase should cover more than just int32x4_t -> svint32_t, > >> >> >> just to be sure. > >> >> > In the attached patch, it obtains corresponding advsimd type with: > >> >> > > >> >> > tree eltype = TREE_TYPE (lhs_type); > >> >> > unsigned nunits = 128 / TREE_INT_CST_LOW (TYPE_SIZE (eltype)); > >> >> > tree vectype = build_vector_type (eltype, nunits); > >> >> > > >> >> > While this seems to work with different element sizes, I am not sure if it's > >> >> > the correct approach ? > >> >> > >> >> Yeah, that looks correct. Other SVE code uses aarch64_vq_mode > >> >> to get the vector mode associated with a .Q “element”, so an > >> >> alternative would be: > >> >> > >> >> machine_mode vq_mode = aarch64_vq_mode (TYPE_MODE (eltype)).require (); > >> >> tree vectype = build_vector_type_for_mode (eltype, vq_mode); > >> >> > >> >> which is more explicit about wanting an Advanced SIMD vector. > >> >> > >> >> >> > + > >> >> >> > + tree elt_ptr_type > >> >> >> > + = build_pointer_type_for_mode (simd_type.eltype, VOIDmode, true); > >> >> >> > + tree zero = build_zero_cst (elt_ptr_type); > >> >> >> > + > >> >> >> > + /* Use element type alignment. */ > >> >> >> > + tree access_type > >> >> >> > + = build_aligned_type (simd_type.itype, TYPE_ALIGN (simd_type.eltype)); > >> >> >> > + > >> >> >> > + tree tmp = make_ssa_name_fn (cfun, access_type, 0); > >> >> >> > + gimple *mem_ref_stmt > >> >> >> > + = gimple_build_assign (tmp, fold_build2 (MEM_REF, access_type, arg1, zero)); > >> >> >> > >> >> >> Long line. Might be easier to format by assigning the fold_build2 result > >> >> >> to a temporary variable. > >> >> >> > >> >> >> > + gsi_insert_before (f.gsi, mem_ref_stmt, GSI_SAME_STMT); > >> >> >> > + > >> >> >> > + tree mem_ref_lhs = gimple_get_lhs (mem_ref_stmt); > >> >> >> > + tree vectype = TREE_TYPE (mem_ref_lhs); > >> >> >> > + tree lhs_type = TREE_TYPE (lhs); > >> >> >> > >> >> >> Is this necessary? The code above supplied the types and I wouldn't > >> >> >> have expected them to change during the build process. > >> >> >> > >> >> >> > + > >> >> >> > + int source_nelts = TYPE_VECTOR_SUBPARTS (vectype).to_constant (); > >> >> >> > + vec_perm_builder sel (TYPE_VECTOR_SUBPARTS (lhs_type), source_nelts, 1); > >> >> >> > + for (int i = 0; i < source_nelts; i++) > >> >> >> > + sel.quick_push (i); > >> >> >> > + > >> >> >> > + vec_perm_indices indices (sel, 1, source_nelts); > >> >> >> > + gcc_checking_assert (can_vec_perm_const_p (TYPE_MODE (lhs_type), indices)); > >> >> >> > + tree mask = vec_perm_indices_to_tree (lhs_type, indices); > >> >> >> > + return gimple_build_assign (lhs, VEC_PERM_EXPR, mem_ref_lhs, mem_ref_lhs, mask); > >> >> >> > >> >> >> Nit: long line. > >> >> >> > >> >> >> > + } > >> >> >> > + > >> >> >> > + return NULL; > >> >> >> > + } > >> >> >> > }; > >> >> >> > > >> >> >> > class svld1ro_impl : public load_replicate > >> >> >> > diff --git a/gcc/config/aarch64/aarch64.cc b/gcc/config/aarch64/aarch64.cc > >> >> >> > index f650abbc4ce..47810fec804 100644 > >> >> >> > --- a/gcc/config/aarch64/aarch64.cc > >> >> >> > +++ b/gcc/config/aarch64/aarch64.cc > >> >> >> > @@ -23969,6 +23969,35 @@ aarch64_evpc_sve_tbl (struct expand_vec_perm_d *d) > >> >> >> > return true; > >> >> >> > } > >> >> >> > > >> >> >> > +/* Try to implement D using SVE dup instruction. */ > >> >> >> > + > >> >> >> > +static bool > >> >> >> > +aarch64_evpc_sve_dup (struct expand_vec_perm_d *d) > >> >> >> > +{ > >> >> >> > + if (BYTES_BIG_ENDIAN > >> >> >> > + || d->perm.length ().is_constant () > >> >> >> > + || !d->one_vector_p > >> >> >> > + || d->target == NULL > >> >> >> > + || d->op0 == NULL > >> >> >> > >> >> >> These last two lines mean that we always return false for d->testing. > >> >> >> The idea instead is that the return value should be the same for both > >> >> >> d->testing and !d->testing. The difference is that for !d->testing we > >> >> >> also emit code to do the permute. > >> >> > >> >> It doesn't look like the new patch addresses this. There should be > >> >> no checks for/uses of “d->target” and “d->op0” until after: > >> >> > >> >> if (d->testing_p) > >> >> return true; > >> >> > >> >> This... > >> >> > >> >> >> > + || GET_MODE_NUNITS (GET_MODE (d->target)).is_constant () > >> >> >> > >> >> >> Sorry, I've forgotten the context now, but: these positive tests > >> >> >> for is_constant surprised me. Do we really only want to do this > >> >> >> for variable-length SVE code generation, rather than fixed-length? > >> >> >> > >> >> >> > + || !GET_MODE_NUNITS (GET_MODE (d->op0)).is_constant ()) > >> >> >> > + return false; > >> >> >> > + > >> >> >> > + if (d->testing_p) > >> >> >> > + return true; > >> >> >> > >> >> >> This should happen after the later tests, once we're sure that the > >> >> >> permute vector has the right form. If the issue is that op0 isn't > >> >> >> provided for testing then I think the hook needs to be passed the > >> >> >> input mode alongside the result mode. > >> >> > >> >> ...was my guess about why the checks were there. > >> > Ah right sorry. IIUC, if d->testing is true, then d->op0 could be NULL ? > >> > In that case, how do we obtain input mode ? > >> > >> Well, like I say, I think we might need to extend the vec_perm_const > >> hook interface so that it gets passed the input mode, now that that > >> isn't necessarily the same as the output mode. > >> > >> It would be good to do that as a separate prepatch, since it would > >> affect other targets too. And for safety, that patch should make all > >> existing implementations of the hook return false if the modes aren't > >> equal, including for aarch64. The current patch can then make the > >> aarch64 hook treat the dup case as an exception. > > Hi Richard, > > I have attached updated patch, which tries to address above suggestions. > > I had a question about couple of things: > > (1) The patch resulted in ICE for float operands, because we were > > using lhs_type to build mask, which is float vector type. > > So I adjusted the patch to make mask vector of integer_type_node with > > length == length(lhs_type) if lhs has float vector type. > > Does that look OK ? > > Let's use: > > build_vector_type (ssizetype, lhs_len) > > unconditionally, even for integers. OK thanks, done in attached patch. > > > (2) Moved check for d->vmode != op_mode (and only checking for dup in > > that case), inside vec_perm_const_1, > > since it does some initial bookkeeping (like swapping operands), > > before calling respective functions. > > Does that look OK ? > > > > Thanks, > > Prathamesh > >> > >> Thanks, > >> Richard > > > > diff --git a/gcc/config/aarch64/aarch64-sve-builtins-base.cc b/gcc/config/aarch64/aarch64-sve-builtins-base.cc > > index bee410929bd..48e849bec34 100644 > > --- a/gcc/config/aarch64/aarch64-sve-builtins-base.cc > > +++ b/gcc/config/aarch64/aarch64-sve-builtins-base.cc > > @@ -44,6 +44,7 @@ > > #include "aarch64-sve-builtins-shapes.h" > > #include "aarch64-sve-builtins-base.h" > > #include "aarch64-sve-builtins-functions.h" > > +#include "ssa.h" > > > > using namespace aarch64_sve; > > > > @@ -1207,6 +1208,66 @@ public: > > insn_code icode = code_for_aarch64_sve_ld1rq (e.vector_mode (0)); > > return e.use_contiguous_load_insn (icode); > > } > > + > > + gimple * > > + fold (gimple_folder &f) const override > > + { > > + tree arg0 = gimple_call_arg (f.call, 0); > > + tree arg1 = gimple_call_arg (f.call, 1); > > + > > + /* Transform: > > + lhs = svld1rq ({-1, -1, ... }, arg1) > > + into: > > + tmp = mem_ref [(int * {ref-all}) arg1] > > + lhs = vec_perm_expr. > > + on little endian target. > > + vectype is the corresponding ADVSIMD type. */ > > + > > + if (!BYTES_BIG_ENDIAN > > + && integer_all_onesp (arg0)) > > + { > > + tree lhs = gimple_call_lhs (f.call); > > + tree lhs_type = TREE_TYPE (lhs); > > + poly_uint64 lhs_len = TYPE_VECTOR_SUBPARTS (lhs_type); > > + tree eltype = TREE_TYPE (lhs_type); > > + > > + scalar_mode elmode = GET_MODE_INNER (TYPE_MODE (lhs_type)); > > + machine_mode vq_mode = aarch64_vq_mode (elmode).require (); > > + tree vectype = build_vector_type_for_mode (eltype, vq_mode); > > + > > + tree elt_ptr_type > > + = build_pointer_type_for_mode (eltype, VOIDmode, true); > > + tree zero = build_zero_cst (elt_ptr_type); > > + > > + /* Use element type alignment. */ > > + tree access_type > > + = build_aligned_type (vectype, TYPE_ALIGN (eltype)); > > + > > + tree mem_ref_lhs = make_ssa_name_fn (cfun, access_type, 0); > > + tree mem_ref_op = fold_build2 (MEM_REF, access_type, arg1, zero); > > + gimple *mem_ref_stmt > > + = gimple_build_assign (mem_ref_lhs, mem_ref_op); > > + gsi_insert_before (f.gsi, mem_ref_stmt, GSI_SAME_STMT); > > + > > + int source_nelts = TYPE_VECTOR_SUBPARTS (access_type).to_constant (); > > + vec_perm_builder sel (lhs_len, source_nelts, 1); > > + for (int i = 0; i < source_nelts; i++) > > + sel.quick_push (i); > > + > > + vec_perm_indices indices (sel, 1, source_nelts); > > + gcc_checking_assert (can_vec_perm_const_p (TYPE_MODE (lhs_type), > > + TYPE_MODE (access_type), > > + indices)); > > + tree mask_type = (FLOAT_TYPE_P (eltype)) > > + ? build_vector_type (integer_type_node, lhs_len) > > + : lhs_type; > > + tree mask = vec_perm_indices_to_tree (mask_type, indices); > > + return gimple_build_assign (lhs, VEC_PERM_EXPR, > > + mem_ref_lhs, mem_ref_lhs, mask); > > + } > > + > > + return NULL; > > + } > > }; > > > > class svld1ro_impl : public load_replicate > > diff --git a/gcc/config/aarch64/aarch64.cc b/gcc/config/aarch64/aarch64.cc > > index d4c575ce976..ae8e913d525 100644 > > --- a/gcc/config/aarch64/aarch64.cc > > +++ b/gcc/config/aarch64/aarch64.cc > > @@ -23401,7 +23401,8 @@ struct expand_vec_perm_d > > bool testing_p; > > }; > > > > -static bool aarch64_expand_vec_perm_const_1 (struct expand_vec_perm_d *d); > > +static bool aarch64_expand_vec_perm_const_1 (struct expand_vec_perm_d *d, > > + machine_mode op_mode); > > > > /* Generate a variable permutation. */ > > > > @@ -23638,7 +23639,7 @@ aarch64_evpc_reencode (struct expand_vec_perm_d *d) > > newd.one_vector_p = d->one_vector_p; > > > > newd.perm.new_vector (newpermconst, newd.one_vector_p ? 1 : 2, nelt / 2); > > - return aarch64_expand_vec_perm_const_1 (&newd); > > + return aarch64_expand_vec_perm_const_1 (&newd, newd.vmode); > > } > > > > /* Recognize patterns suitable for the UZP instructions. */ > > @@ -23945,6 +23946,32 @@ aarch64_evpc_sve_tbl (struct expand_vec_perm_d *d) > > return true; > > } > > > > +/* Try to implement D using SVE dup instruction. */ > > + > > +static bool > > +aarch64_evpc_sve_dup (struct expand_vec_perm_d *d, machine_mode op_mode) > > +{ > > + if (BYTES_BIG_ENDIAN > > + || d->perm.length ().is_constant () > > Sorry, I've forgotten: why do we need this is_constant check? Oh I guess I had put it there, to check if target vector is of variable length, sorry. I assume we don't need this. Removed in the attached patch. > > > + || !d->one_vector_p > > + || aarch64_classify_vector_mode (op_mode) != VEC_ADVSIMD) > > + return false; > > We need to check that nelts_per_pattern is 1 as well. OK thanks, done. > > > + int npatterns = d->perm.encoding ().npatterns (); > > + if (!known_eq (npatterns, GET_MODE_NUNITS (op_mode))) > > + return false; > > + > > + for (int i = 0; i < npatterns; i++) > > + if (!known_eq (d->perm[i], i)) > > + return false; > > + > > + if (d->testing_p) > > + return true; > > + > > + aarch64_expand_sve_dupq (d->target, GET_MODE (d->target), d->op0); > > + return true; > > +} > > + > > /* Try to implement D using SVE SEL instruction. */ > > > > static bool > > @@ -24066,7 +24093,8 @@ aarch64_evpc_ins (struct expand_vec_perm_d *d) > > } > > > > static bool > > -aarch64_expand_vec_perm_const_1 (struct expand_vec_perm_d *d) > > +aarch64_expand_vec_perm_const_1 (struct expand_vec_perm_d *d, > > + machine_mode op_mode) > > I think we should add op_mode to expand_vec_perm_d instead. > Let's also add an op_vec_flags to cache the aarch64_classify_vector_mode > result. OK thanks, done. > > > { > > /* The pattern matching functions above are written to look for a small > > number to begin the sequence (0, 1, N/2). If we begin with an index > > @@ -24084,6 +24112,12 @@ aarch64_expand_vec_perm_const_1 (struct expand_vec_perm_d *d) > > || d->vec_flags == VEC_SVE_PRED) > > && known_gt (nelt, 1)) > > { > > + /* If operand and result modes differ, then only check > > + for dup case. */ > > + if (d->vmode != op_mode) > > + return (d->vec_flags == VEC_SVE_DATA) > > + ? aarch64_evpc_sve_dup (d, op_mode) : false; > > + > > I think it'd be more future-proof to format this as: > > if (d->vmod == d->op_mode) > { > …existing code… > } > else > { > if (aarch64_evpc_sve_dup (d)) > return true; > } > > with the d->vec_flags == VEC_SVE_DATA check being in aarch64_evpc_sve_dup, > alongside the op_mode check. I think we'll be adding more checks here > over time. Um I was wondering if we should structure it as: if (d->vmode == d->op_mode) { ...existing code... } if (aarch64_evpc_sve_dup (d)) return true; So we check for dup irrespective of d->vmode == d->op_mode ? Thanks, Prathamesh > > > if (aarch64_evpc_rev_local (d)) > > return true; > > else if (aarch64_evpc_rev_global (d)) > > @@ -24105,7 +24139,12 @@ aarch64_expand_vec_perm_const_1 (struct expand_vec_perm_d *d) > > else if (aarch64_evpc_reencode (d)) > > return true; > > if (d->vec_flags == VEC_SVE_DATA) > > - return aarch64_evpc_sve_tbl (d); > > + { > > + if (aarch64_evpc_sve_tbl (d)) > > + return true; > > + else if (aarch64_evpc_sve_dup (d, op_mode)) > > + return true; > > + } > > else if (d->vec_flags == VEC_ADVSIMD) > > return aarch64_evpc_tbl (d); > > } > > Is this part still needed, given the above? > > Thanks, > Richard > > > @@ -24119,9 +24158,6 @@ aarch64_vectorize_vec_perm_const (machine_mode vmode, machine_mode op_mode, > > rtx target, rtx op0, rtx op1, > > const vec_perm_indices &sel) > > { > > - if (vmode != op_mode) > > - return false; > > - > > struct expand_vec_perm_d d; > > > > /* Check whether the mask can be applied to a single vector. */ > > @@ -24154,10 +24190,10 @@ aarch64_vectorize_vec_perm_const (machine_mode vmode, machine_mode op_mode, > > d.testing_p = !target; > > > > if (!d.testing_p) > > - return aarch64_expand_vec_perm_const_1 (&d); > > + return aarch64_expand_vec_perm_const_1 (&d, op_mode); > > > > rtx_insn *last = get_last_insn (); > > - bool ret = aarch64_expand_vec_perm_const_1 (&d); > > + bool ret = aarch64_expand_vec_perm_const_1 (&d, op_mode); > > gcc_assert (last == get_last_insn ()); > > > > return ret;