On Tue, 12 Jun 2012, William J. Schmidt wrote: > This patch is a follow-up to the discussion generated by > http://gcc.gnu.org/ml/gcc-patches/2012-06/msg00546.html. I've added > vec_construct to the cost model for use in vect_model_load_cost, and > implemented a cost calculation that makes sense to me for PowerPC. I'm > less certain about the default, i386, and spu implementations. I took a > guess at i386 from the discussions we had, and used the same calculation > for the default and for spu. I'm hoping you or others can fill in the > blanks if I guessed badly. > > The i386 cost for vec_construct is different from all the others, which > are parameterized for each processor description. This should probably > be parameterized in some way as well, but thought you'd know better than > I how that should be. Perhaps instead of > > elements / 2 + 1 > > it should be > > (elements / 2) * X + Y > > where X and Y are taken from the processor description, and represent > the cost of a merge and a permute, respectively. Let me know what you > think. Looks good to me with the gcc_asserts removed - TYPE_VECTOR_SUBPARTS might be 1 for V1TImode for example (heh, not that the vectorizer would vectorize to that). But I don't see any possible breakage with elements == 1, do you? Target maintainers can improve on the cost calculation if they wish, the default looks sensible to me. Thanks, Richard. > Thanks, > Bill > > > 2012-06-12 Bill Schmidt > > * targhooks.c (default_builtin_vectorized_conversion): Handle > vec_construct, using vectype to base cost on subparts. > * target.h (enum vect_cost_for_stmt): Add vec_construct. > * tree-vect-stmts.c (vect_model_load_cost): Use vec_construct > instead of scalar_to-vec. > * config/spu/spu.c (spu_builtin_vectorization_cost): Handle > vec_construct in same way as default for now. > * config/i386/i386.c (ix86_builtin_vectorization_cost): Likewise. > * config/rs6000/rs6000.c (rs6000_builtin_vectorization_cost): > Handle vec_construct, including special case for 32-bit loads. > > > Index: gcc/targhooks.c > =================================================================== > --- gcc/targhooks.c (revision 188482) > +++ gcc/targhooks.c (working copy) > @@ -499,9 +499,11 @@ default_builtin_vectorized_conversion (unsigned in > > int > default_builtin_vectorization_cost (enum vect_cost_for_stmt type_of_cost, > - tree vectype ATTRIBUTE_UNUSED, > + tree vectype, > int misalign ATTRIBUTE_UNUSED) > { > + unsigned elements; > + > switch (type_of_cost) > { > case scalar_stmt: > @@ -524,6 +526,11 @@ default_builtin_vectorization_cost (enum vect_cost > case cond_branch_taken: > return 3; > > + case vec_construct: > + elements = TYPE_VECTOR_SUBPARTS (vectype); > + gcc_assert (elements > 1); > + return elements / 2 + 1; > + > default: > gcc_unreachable (); > } > Index: gcc/target.h > =================================================================== > --- gcc/target.h (revision 188482) > +++ gcc/target.h (working copy) > @@ -146,7 +146,8 @@ enum vect_cost_for_stmt > cond_branch_not_taken, > cond_branch_taken, > vec_perm, > - vec_promote_demote > + vec_promote_demote, > + vec_construct > }; > > /* The target structure. This holds all the backend hooks. */ > Index: gcc/tree-vect-stmts.c > =================================================================== > --- gcc/tree-vect-stmts.c (revision 188482) > +++ gcc/tree-vect-stmts.c (working copy) > @@ -1031,11 +1031,13 @@ vect_model_load_cost (stmt_vec_info stmt_info, int > /* The loads themselves. */ > if (STMT_VINFO_STRIDE_LOAD_P (stmt_info)) > { > - /* N scalar loads plus gathering them into a vector. > - ??? scalar_to_vec isn't the cost for that. */ > + /* N scalar loads plus gathering them into a vector. */ > + tree vectype = STMT_VINFO_VECTYPE (stmt_info); > inside_cost += (vect_get_stmt_cost (scalar_load) * ncopies > - * TYPE_VECTOR_SUBPARTS (STMT_VINFO_VECTYPE (stmt_info))); > - inside_cost += ncopies * vect_get_stmt_cost (scalar_to_vec); > + * TYPE_VECTOR_SUBPARTS (vectype)); > + inside_cost += ncopies > + * targetm.vectorize.builtin_vectorization_cost (vec_construct, > + vectype, 0); > } > else > vect_get_load_cost (first_dr, ncopies, > Index: gcc/config/spu/spu.c > =================================================================== > --- gcc/config/spu/spu.c (revision 188482) > +++ gcc/config/spu/spu.c (working copy) > @@ -6908,9 +6908,11 @@ spu_builtin_mask_for_load (void) > /* Implement targetm.vectorize.builtin_vectorization_cost. */ > static int > spu_builtin_vectorization_cost (enum vect_cost_for_stmt type_of_cost, > - tree vectype ATTRIBUTE_UNUSED, > + tree vectype, > int misalign ATTRIBUTE_UNUSED) > { > + unsigned elements; > + > switch (type_of_cost) > { > case scalar_stmt: > @@ -6937,6 +6939,11 @@ spu_builtin_vectorization_cost (enum vect_cost_for > case cond_branch_taken: > return 6; > > + case vec_construct: > + elements = TYPE_VECTOR_SUBPARTS (vectype); > + gcc_assert (elements > 1); > + return elements / 2 + 1; > + > default: > gcc_unreachable (); > } > Index: gcc/config/i386/i386.c > =================================================================== > --- gcc/config/i386/i386.c (revision 188482) > +++ gcc/config/i386/i386.c (working copy) > @@ -36072,9 +36072,11 @@ static const struct attribute_spec ix86_attribute_ > /* Implement targetm.vectorize.builtin_vectorization_cost. */ > static int > ix86_builtin_vectorization_cost (enum vect_cost_for_stmt type_of_cost, > - tree vectype ATTRIBUTE_UNUSED, > + tree vectype, > int misalign ATTRIBUTE_UNUSED) > { > + unsigned elements; > + > switch (type_of_cost) > { > case scalar_stmt: > @@ -36115,6 +36117,11 @@ ix86_builtin_vectorization_cost (enum vect_cost_fo > case vec_promote_demote: > return ix86_cost->vec_stmt_cost; > > + case vec_construct: > + elements = TYPE_VECTOR_SUBPARTS (vectype); > + gcc_assert (elements > 1); > + return elements / 2 + 1; > + > default: > gcc_unreachable (); > } > Index: gcc/config/rs6000/rs6000.c > =================================================================== > --- gcc/config/rs6000/rs6000.c (revision 188482) > +++ gcc/config/rs6000/rs6000.c (working copy) > @@ -3405,6 +3405,7 @@ rs6000_builtin_vectorization_cost (enum vect_cost_ > tree vectype, int misalign) > { > unsigned elements; > + tree elem_type; > > switch (type_of_cost) > { > @@ -3504,6 +3505,19 @@ rs6000_builtin_vectorization_cost (enum vect_cost_ > > return 2; > > + case vec_construct: > + elements = TYPE_VECTOR_SUBPARTS (vectype); > + elem_type = TREE_TYPE (vectype); > + gcc_assert (elements > 1); > + /* 32-bit vectors loaded into registers are stored as double > + precision, so we need n/2 converts in addition to the usual > + n/2 merges to construct a vector of short floats from them. */ > + if (SCALAR_FLOAT_TYPE_P (elem_type) > + && TYPE_PRECISION (elem_type) == 32) > + return elements + 1; > + else > + return elements / 2 + 1; > + > default: > gcc_unreachable (); > } > > > -- Richard Guenther SUSE / SUSE Labs SUSE LINUX Products GmbH - Nuernberg - AG Nuernberg - HRB 16746 GF: Jeff Hawn, Jennifer Guild, Felix Imendörffer