On Tue, 2017-09-12 at 10:22 -0500, Bill Schmidt wrote:
> > On Sep 12, 2017, at 9:41 AM, Will Schmidt <will_schm...@vnet.ibm.com> wrote:
> >
> > Hi
> >
> > [PATCH, rs6000] Folding of vector loads in GIMPLE
> >
> > Folding of vector loads in GIMPLE.
> >
> > - Add code to handle gimple folding for the vec_ld builtins.
> > - Remove the now obsoleted folding code for vec_ld from rs6000-c.c.
> > Surrounding
> > comments have been adjusted slightly so they continue to read OK for the
> > vec_st code that remains.
> >
> > The resulting code is specifically verified by the powerpc/fold-vec-ld-*.c
> > tests which have been posted separately. (a few minutes ago).
> >
> > Regtest successfully completed on power6 and newer. (p6,p7,p8le,p8be,p9).
> >
> > OK for trunk?
> >
> > Thanks,
> > -Will
> >
> > [gcc]
> >
> > 2017-09-12 Will Schmidt <will_schm...@vnet.ibm.com>
> >
> > * config/rs6000/rs6000.c (rs6000_gimple_fold_builtin): Add handling
> > for early folding of vector loads (ALTIVEC_BUILTIN_LVX_*).
> > * config/rs6000/rs6000-c.c (altivec_resolve_overloaded_builtin):
> > Remove obsoleted code for handling ALTIVEC_BUILTIN_VEC_LD.
> >
> > diff --git a/gcc/config/rs6000/rs6000-c.c b/gcc/config/rs6000/rs6000-c.c
> > index 897306c..73e14d9 100644
> > --- a/gcc/config/rs6000/rs6000-c.c
> > +++ b/gcc/config/rs6000/rs6000-c.c
> > @@ -6459,92 +6459,19 @@ altivec_resolve_overloaded_builtin (location_t loc,
> > tree fndecl,
> > convert (TREE_TYPE (stmt), arg0));
> > stmt = build2 (COMPOUND_EXPR, arg1_type, stmt, decl);
> > return stmt;
> > }
> >
> > - /* Expand vec_ld into an expression that masks the address and
> > - performs the load. We need to expand this early to allow
> > + /* Expand vec_st into an expression that masks the address and
> > + performs the store. We need to expand this early to allow
> > the best aliasing, as by the time we get into RTL we no longer
> > are able to honor __restrict__, for example. We may want to
> > consider this for all memory access built-ins.
> >
> > When -maltivec=be is specified, or the wrong number of arguments
> > is provided, simply punt to existing built-in processing. */
> > - if (fcode == ALTIVEC_BUILTIN_VEC_LD
> > - && (BYTES_BIG_ENDIAN || !VECTOR_ELT_ORDER_BIG)
> > - && nargs == 2)
> > - {
> > - tree arg0 = (*arglist)[0];
> > - tree arg1 = (*arglist)[1];
> > -
> > - /* Strip qualifiers like "const" from the pointer arg. */
> > - tree arg1_type = TREE_TYPE (arg1);
> > - if (!POINTER_TYPE_P (arg1_type) && TREE_CODE (arg1_type) !=
> > ARRAY_TYPE)
> > - goto bad;
> > -
> > - tree inner_type = TREE_TYPE (arg1_type);
> > - if (TYPE_QUALS (TREE_TYPE (arg1_type)) != 0)
> > - {
> > - arg1_type = build_pointer_type (build_qualified_type (inner_type,
> > - 0));
> > - arg1 = fold_convert (arg1_type, arg1);
> > - }
> > -
> > - /* Construct the masked address. Let existing error handling take
> > - over if we don't have a constant offset. */
> > - arg0 = fold (arg0);
> > -
> > - if (TREE_CODE (arg0) == INTEGER_CST)
> > - {
> > - if (!ptrofftype_p (TREE_TYPE (arg0)))
> > - arg0 = build1 (NOP_EXPR, sizetype, arg0);
> > -
> > - tree arg1_type = TREE_TYPE (arg1);
> > - if (TREE_CODE (arg1_type) == ARRAY_TYPE)
> > - {
> > - arg1_type = TYPE_POINTER_TO (TREE_TYPE (arg1_type));
> > - tree const0 = build_int_cstu (sizetype, 0);
> > - tree arg1_elt0 = build_array_ref (loc, arg1, const0);
> > - arg1 = build1 (ADDR_EXPR, arg1_type, arg1_elt0);
> > - }
> > -
> > - tree addr = fold_build2_loc (loc, POINTER_PLUS_EXPR, arg1_type,
> > - arg1, arg0);
> > - tree aligned = fold_build2_loc (loc, BIT_AND_EXPR, arg1_type, addr,
> > - build_int_cst (arg1_type, -16));
> > -
> > - /* Find the built-in to get the return type so we can convert
> > - the result properly (or fall back to default handling if the
> > - arguments aren't compatible). */
> > - for (desc = altivec_overloaded_builtins;
> > - desc->code && desc->code != fcode; desc++)
> > - continue;
> > -
> > - for (; desc->code == fcode; desc++)
> > - if (rs6000_builtin_type_compatible (TREE_TYPE (arg0), desc->op1)
> > - && (rs6000_builtin_type_compatible (TREE_TYPE (arg1),
> > - desc->op2)))
> > - {
> > - tree ret_type = rs6000_builtin_type (desc->ret_type);
> > - if (TYPE_MODE (ret_type) == V2DImode)
> > - /* Type-based aliasing analysis thinks vector long
> > - and vector long long are different and will put them
> > - in distinct alias classes. Force our return type
> > - to be a may-alias type to avoid this. */
> > - ret_type
> > - = build_pointer_type_for_mode (ret_type, Pmode,
> > - true/*can_alias_all*/);
> > - else
> > - ret_type = build_pointer_type (ret_type);
> > - aligned = build1 (NOP_EXPR, ret_type, aligned);
> > - tree ret_val = build_indirect_ref (loc, aligned, RO_NULL);
> > - return ret_val;
> > - }
> > - }
> > - }
> >
> > - /* Similarly for stvx. */
> > if (fcode == ALTIVEC_BUILTIN_VEC_ST
> > && (BYTES_BIG_ENDIAN || !VECTOR_ELT_ORDER_BIG)
> > && nargs == 3)
> > {
> > tree arg0 = (*arglist)[0];
> > diff --git a/gcc/config/rs6000/rs6000.c b/gcc/config/rs6000/rs6000.c
> > index cf744d8..5b14789 100644
> > --- a/gcc/config/rs6000/rs6000.c
> > +++ b/gcc/config/rs6000/rs6000.c
> > @@ -16473,10 +16473,65 @@ rs6000_gimple_fold_builtin (gimple_stmt_iterator
> > *gsi)
> > res = gimple_build (&stmts, VIEW_CONVERT_EXPR, TREE_TYPE (lhs), res);
> > gsi_insert_seq_before (gsi, stmts, GSI_SAME_STMT);
> > update_call_from_tree (gsi, res);
> > return true;
> > }
> > + /* Vector loads. */
> > + case ALTIVEC_BUILTIN_LVX_V16QI:
> > + case ALTIVEC_BUILTIN_LVX_V8HI:
> > + case ALTIVEC_BUILTIN_LVX_V4SI:
> > + case ALTIVEC_BUILTIN_LVX_V4SF:
> > + case ALTIVEC_BUILTIN_LVX_V2DI:
> > + case ALTIVEC_BUILTIN_LVX_V2DF:
> > + {
> > + gimple *g;
> > + arg0 = gimple_call_arg (stmt, 0); // offset
> > + arg1 = gimple_call_arg (stmt, 1); // address
> > +
> > + /* Limit folding of loads to LE targets. */
> > + if (BYTES_BIG_ENDIAN || VECTOR_ELT_ORDER_BIG)
> > + return false;
>
> Why? This transformation shouldn't be endian-dependent.
I was seeing errors in some of the existing tests specific to BE.
FAIL: gcc.dg/vmx/ld-be-order.c -Os execution test
FAIL: gcc.dg/vmx/ld-vsx-be-order.c -O0 execution test
I'll give this another attempt without that exclusion and verify. I'll
admit it is possible the ld*be-order tests were failing for other
reasons.
Thanks
-Will
>
> Thanks,
> Bill
>
> > +
> > + lhs = gimple_call_lhs (stmt);
> > + location_t loc = gimple_location (stmt);
> > +
> > + tree arg1_type = TREE_TYPE (arg1);
> > + tree lhs_type = TREE_TYPE (lhs);
> > +
> > + /* POINTER_PLUS_EXPR wants the offset to be of type 'sizetype'. Create
> > + the tree using the value from arg0. The resulting type will match
> > + the type of arg1. */
> > + tree temp_offset = create_tmp_reg_or_ssa_name (sizetype);
> > + g = gimple_build_assign (temp_offset, NOP_EXPR, arg0);
> > + gimple_set_location (g, loc);
> > + gsi_insert_before (gsi, g, GSI_SAME_STMT);
> > + tree temp_addr = create_tmp_reg_or_ssa_name (arg1_type);
> > + g = gimple_build_assign (temp_addr, POINTER_PLUS_EXPR, arg1,
> > + temp_offset);
> > + gimple_set_location (g, loc);
> > + gsi_insert_before (gsi, g, GSI_SAME_STMT);
> > +
> > + /* Mask off any lower bits from the address. */
> > + tree alignment_mask = build_int_cst (arg1_type, -16);
> > + tree aligned_addr = create_tmp_reg_or_ssa_name (arg1_type);
> > + g = gimple_build_assign (aligned_addr, BIT_AND_EXPR,
> > + temp_addr, alignment_mask);
> > + gimple_set_location (g, loc);
> > + gsi_insert_before (gsi, g, GSI_SAME_STMT);
> > +
> > + /* Use the build2 helper to set up the mem_ref. The MEM_REF could also
> > + take an offset, but since we've already incorporated the offset
> > + above, here we just pass in a zero. */
> > + g = gimple_build_assign (lhs, build2 (MEM_REF, lhs_type, aligned_addr,
> > + build_int_cst (arg1_type, 0)));
> > + gimple_set_location (g, loc);
> > + gsi_replace (gsi, g, true);
> > +
> > + return true;
> > +
> > + }
> > +
> > default:
> > if (TARGET_DEBUG_BUILTIN)
> > fprintf (stderr, "gimple builtin intrinsic not matched:%d %s %s\n",
> > fn_code, fn_name1, fn_name2);
> > break;
> >
> >
>
