On 6/12/18 11:56 AM, Will Schmidt wrote:
> Hi,
> Gimple folding for unaligned vector loads and stores.
> Regtest completed across variety of systems, P6,P7,P8,P9.
>
> [v2] Added the type for the MEM_REF, per feedback.
> Testcases for gimple-folding of the same are currently in-tree
> as powerpc/fold-vec-load-*.c and powerpc/fold-vec-store-*.c.
> Re-tested, still looks good. :-)
>
> Thanks
> -Will
>
> [gcc]
>
> 2018-06-12 Will Schmidt <will_schm...@vnet.ibm.com>
>
> * config/rs6000/rs6000.c (rs6000_builtin_valid_without_lhs): Add
> vec_xst variants to the list.
> (rs6000_gimple_fold_builtin): Add support for folding unaligned
> vector loads and stores.
>
> diff --git a/gcc/config/rs6000/rs6000.c b/gcc/config/rs6000/rs6000.c
> index d62abdf..374666c 100644
> --- a/gcc/config/rs6000/rs6000.c
> +++ b/gcc/config/rs6000/rs6000.c
> @@ -15360,10 +15360,16 @@ rs6000_builtin_valid_without_lhs (enum
> rs6000_builtins fn_code)
> case ALTIVEC_BUILTIN_STVX_V8HI:
> case ALTIVEC_BUILTIN_STVX_V4SI:
> case ALTIVEC_BUILTIN_STVX_V4SF:
> case ALTIVEC_BUILTIN_STVX_V2DI:
> case ALTIVEC_BUILTIN_STVX_V2DF:
> + case VSX_BUILTIN_STXVW4X_V16QI:
> + case VSX_BUILTIN_STXVW4X_V8HI:
> + case VSX_BUILTIN_STXVW4X_V4SF:
> + case VSX_BUILTIN_STXVW4X_V4SI:
> + case VSX_BUILTIN_STXVD2X_V2DF:
> + case VSX_BUILTIN_STXVD2X_V2DI:
> return true;
> default:
> return false;
> }
> }
> @@ -15869,10 +15875,78 @@ rs6000_gimple_fold_builtin (gimple_stmt_iterator
> *gsi)
> gimple_set_location (g, loc);
> gsi_replace (gsi, g, true);
> return true;
> }
>
> + /* unaligned Vector loads. */
> + case VSX_BUILTIN_LXVW4X_V16QI:
> + case VSX_BUILTIN_LXVW4X_V8HI:
> + case VSX_BUILTIN_LXVW4X_V4SF:
> + case VSX_BUILTIN_LXVW4X_V4SI:
> + case VSX_BUILTIN_LXVD2X_V2DF:
> + case VSX_BUILTIN_LXVD2X_V2DI:
> + {
> + arg0 = gimple_call_arg (stmt, 0); // offset
> + arg1 = gimple_call_arg (stmt, 1); // address
> + lhs = gimple_call_lhs (stmt);
> + location_t loc = gimple_location (stmt);
> + /* Since arg1 may be cast to a different type, just use ptr_type_node
> + here instead of trying to enforce TBAA on pointer types. */
> + tree arg1_type = ptr_type_node;
> + 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. */
> + gimple_seq stmts = NULL;
> + tree temp_offset = gimple_convert (&stmts, loc, sizetype, arg0);
> + tree temp_addr = gimple_build (&stmts, loc, POINTER_PLUS_EXPR,
> + arg1_type, arg1, temp_offset);
> + gsi_insert_seq_before (gsi, stmts, 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. */
> + gimple *g;
> + tree align_ltype = build_aligned_type (lhs_type, TYPE_ALIGN
> ((lhs_type)));
This alignment is too strong (assuming lhs is a vector type). lxvd2x and
lxvw4x only
require word alignment, so
tree align_ltype = build_aligned_type (lhs_type, 4);
seems like what you need. See my earlier discussion with Richard. Sorry I
didn't
notice this before!
> + g = gimple_build_assign (lhs, build2 (MEM_REF, align_ltype, temp_addr,
> + build_int_cst (arg1_type, 0)));
> + gimple_set_location (g, loc);
> + gsi_replace (gsi, g, true);
> + return true;
> + }
> +
> + /* unaligned Vector stores. */
> + case VSX_BUILTIN_STXVW4X_V16QI:
> + case VSX_BUILTIN_STXVW4X_V8HI:
> + case VSX_BUILTIN_STXVW4X_V4SF:
> + case VSX_BUILTIN_STXVW4X_V4SI:
> + case VSX_BUILTIN_STXVD2X_V2DF:
> + case VSX_BUILTIN_STXVD2X_V2DI:
> + {
> + arg0 = gimple_call_arg (stmt, 0); /* Value to be stored. */
> + arg1 = gimple_call_arg (stmt, 1); /* Offset. */
> + tree arg2 = gimple_call_arg (stmt, 2); /* Store-to address. */
> + location_t loc = gimple_location (stmt);
> + tree arg0_type = TREE_TYPE (arg0);
> + /* Use ptr_type_node (no TBAA) for the arg2_type. */
> + tree arg2_type = ptr_type_node;
> + /* 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 arg2. */
> + gimple_seq stmts = NULL;
> + tree temp_offset = gimple_convert (&stmts, loc, sizetype, arg1);
> + tree temp_addr = gimple_build (&stmts, loc, POINTER_PLUS_EXPR,
> + arg2_type, arg2, temp_offset);
> + /* Mask off any lower bits from the address. */
Spurious comment? You're not doing that, nor do you want to...
Thanks,
Bill
> + gsi_insert_seq_before (gsi, stmts, GSI_SAME_STMT);
> + gimple *g;
> + g = gimple_build_assign (build2 (MEM_REF, arg0_type, temp_addr,
> + build_int_cst (arg2_type, 0)), arg0);
> + gimple_set_location (g, loc);
> + gsi_replace (gsi, g, true);
> + return true;
> + }
> +
> /* Vector Fused multiply-add (fma). */
> case ALTIVEC_BUILTIN_VMADDFP:
> case VSX_BUILTIN_XVMADDDP:
> case ALTIVEC_BUILTIN_VMLADDUHM:
> {
>
>
