https://gcc.gnu.org/g:792adb8d222d0d1d16b182871e105f47823b8e72
commit r15-3093-g792adb8d222d0d1d16b182871e105f47823b8e72 Author: Prathamesh Kulkarni <prathame...@nvidia.com> Date: Thu Aug 22 19:25:20 2024 +0530 Recompute TYPE_MODE and DECL_MODE for aggregate type for acclerator. The patch streams out VOIDmode for aggregate types with offloading enabled, and recomputes appropriate TYPE_MODE and DECL_MODE while streaming-in on accel side. The rationale for this change is to avoid streaming out host-specific modes that may be used for aggregate types, which may not be representable on the accelerator. For eg, AArch64 uses OImode for ARRAY_TYPE whose size is 256-bits, and nvptx doesn't have OImode, and thus ends up emitting an error from lto_input_mode_table. gcc/ChangeLog: * lto-streamer-in.cc: (lto_read_tree_1): Set DECL_MODE (expr) to TREE_TYPE (TYPE_MODE (expr)) if TREE_TYPE (expr) is aggregate type and offloading is enabled. * stor-layout.cc (layout_type): Move computation of mode for ARRAY_TYPE from ... (compute_array_mode): ... to here. * stor-layout.h (compute_array_mode): Declare. * tree-streamer-in.cc: Include stor-layout.h. (unpack_ts_common_value_fields): Call compute_array_mode if offloading is enabled. * tree-streamer-out.cc (pack_ts_fixed_cst_value_fields): Stream out VOIDmode if decl has aggregate type and offloading is enabled. (pack_ts_type_common_value_fields): Stream out VOIDmode for aggregate type if offloading is enabled. Signed-off-by: Prathamesh Kulkarni <prathame...@nvidia.com> Diff: --- gcc/lto-streamer-in.cc | 9 +++++++++ gcc/stor-layout.cc | 45 +++++++++++++++++++++++++++------------------ gcc/stor-layout.h | 1 + gcc/tree-streamer-in.cc | 12 ++++++++++++ gcc/tree-streamer-out.cc | 22 ++++++++++++++++++++-- 5 files changed, 69 insertions(+), 20 deletions(-) diff --git a/gcc/lto-streamer-in.cc b/gcc/lto-streamer-in.cc index cbf6041fd685..64f758073280 100644 --- a/gcc/lto-streamer-in.cc +++ b/gcc/lto-streamer-in.cc @@ -1752,6 +1752,15 @@ lto_read_tree_1 (class lto_input_block *ib, class data_in *data_in, tree expr) with -g1, see for example PR113488. */ else if (DECL_P (expr) && DECL_ABSTRACT_ORIGIN (expr) == expr) DECL_ABSTRACT_ORIGIN (expr) = NULL_TREE; + +#ifdef ACCEL_COMPILER + if ((VAR_P (expr) + || TREE_CODE (expr) == PARM_DECL + || TREE_CODE (expr) == FIELD_DECL) + && AGGREGATE_TYPE_P (TREE_TYPE (expr)) + && DECL_MODE (expr) == VOIDmode) + SET_DECL_MODE (expr, TYPE_MODE (TREE_TYPE (expr))); +#endif } } diff --git a/gcc/stor-layout.cc b/gcc/stor-layout.cc index 10c0809914cd..0ff8bd1171e1 100644 --- a/gcc/stor-layout.cc +++ b/gcc/stor-layout.cc @@ -2396,6 +2396,32 @@ finish_builtin_struct (tree type, const char *name, tree fields, layout_decl (TYPE_NAME (type), 0); } +/* Compute TYPE_MODE for TYPE (which is ARRAY_TYPE). */ + +void compute_array_mode (tree type) +{ + gcc_assert (TREE_CODE (type) == ARRAY_TYPE); + + SET_TYPE_MODE (type, BLKmode); + if (TYPE_SIZE (type) != 0 + && ! targetm.member_type_forces_blk (type, VOIDmode) + /* BLKmode elements force BLKmode aggregate; + else extract/store fields may lose. */ + && (TYPE_MODE (TREE_TYPE (type)) != BLKmode + || TYPE_NO_FORCE_BLK (TREE_TYPE (type)))) + { + SET_TYPE_MODE (type, mode_for_array (TREE_TYPE (type), + TYPE_SIZE (type))); + if (TYPE_MODE (type) != BLKmode + && STRICT_ALIGNMENT && TYPE_ALIGN (type) < BIGGEST_ALIGNMENT + && TYPE_ALIGN (type) < GET_MODE_ALIGNMENT (TYPE_MODE (type))) + { + TYPE_NO_FORCE_BLK (type) = 1; + SET_TYPE_MODE (type, BLKmode); + } + } +} + /* Calculate the mode, size, and alignment for TYPE. For an array type, calculate the element separation as well. Record TYPE on the chain of permanent or temporary types @@ -2709,24 +2735,7 @@ layout_type (tree type) align = MAX (align, BITS_PER_UNIT); #endif SET_TYPE_ALIGN (type, align); - SET_TYPE_MODE (type, BLKmode); - if (TYPE_SIZE (type) != 0 - && ! targetm.member_type_forces_blk (type, VOIDmode) - /* BLKmode elements force BLKmode aggregate; - else extract/store fields may lose. */ - && (TYPE_MODE (TREE_TYPE (type)) != BLKmode - || TYPE_NO_FORCE_BLK (TREE_TYPE (type)))) - { - SET_TYPE_MODE (type, mode_for_array (TREE_TYPE (type), - TYPE_SIZE (type))); - if (TYPE_MODE (type) != BLKmode - && STRICT_ALIGNMENT && TYPE_ALIGN (type) < BIGGEST_ALIGNMENT - && TYPE_ALIGN (type) < GET_MODE_ALIGNMENT (TYPE_MODE (type))) - { - TYPE_NO_FORCE_BLK (type) = 1; - SET_TYPE_MODE (type, BLKmode); - } - } + compute_array_mode (type); if (AGGREGATE_TYPE_P (element)) TYPE_TYPELESS_STORAGE (type) = TYPE_TYPELESS_STORAGE (element); /* When the element size is constant, check that it is at least as diff --git a/gcc/stor-layout.h b/gcc/stor-layout.h index 096ca8117627..9d9b8c385f60 100644 --- a/gcc/stor-layout.h +++ b/gcc/stor-layout.h @@ -34,6 +34,7 @@ extern tree rli_size_so_far (record_layout_info); extern void normalize_rli (record_layout_info); extern void place_field (record_layout_info, tree); extern void compute_record_mode (tree); +extern void compute_array_mode (tree); extern void finish_bitfield_layout (tree); extern void finish_record_layout (record_layout_info, int); extern void finalize_size_functions (void); diff --git a/gcc/tree-streamer-in.cc b/gcc/tree-streamer-in.cc index 40029437199c..329d218e7d4e 100644 --- a/gcc/tree-streamer-in.cc +++ b/gcc/tree-streamer-in.cc @@ -35,6 +35,7 @@ along with GCC; see the file COPYING3. If not see #include "attribs.h" #include "asan.h" #include "opts.h" +#include "stor-layout.h" /* Read a STRING_CST from the string table in DATA_IN using input @@ -395,6 +396,17 @@ unpack_ts_type_common_value_fields (struct bitpack_d *bp, tree expr) #ifdef ACCEL_COMPILER if (TYPE_ALIGN (expr) > targetm.absolute_biggest_alignment) SET_TYPE_ALIGN (expr, targetm.absolute_biggest_alignment); + + /* Host streams out VOIDmode for aggregate type. */ + if (AGGREGATE_TYPE_P (expr) && TYPE_MODE (expr) == VOIDmode) + { + if (TREE_CODE (expr) == ARRAY_TYPE) + compute_array_mode (expr); + else if (RECORD_OR_UNION_TYPE_P (expr)) + compute_record_mode (expr); + else + gcc_unreachable (); + } #endif } diff --git a/gcc/tree-streamer-out.cc b/gcc/tree-streamer-out.cc index b7205287ffb6..7de4447a1b53 100644 --- a/gcc/tree-streamer-out.cc +++ b/gcc/tree-streamer-out.cc @@ -187,7 +187,17 @@ pack_ts_fixed_cst_value_fields (struct bitpack_d *bp, tree expr) static void pack_ts_decl_common_value_fields (struct bitpack_d *bp, tree expr) { - bp_pack_machine_mode (bp, DECL_MODE (expr)); + /* Similar to TYPE_MODE, avoid streaming out host-specific DECL_MODE + for aggregate type with offloading enabled, and while streaming-in + recompute appropriate DECL_MODE for accelerator. */ + if (lto_stream_offload_p + && (VAR_P (expr) + || TREE_CODE (expr) == PARM_DECL + || TREE_CODE (expr) == FIELD_DECL) + && AGGREGATE_TYPE_P (TREE_TYPE (expr))) + bp_pack_machine_mode (bp, VOIDmode); + else + bp_pack_machine_mode (bp, DECL_MODE (expr)); bp_pack_value (bp, DECL_NONLOCAL (expr), 1); bp_pack_value (bp, DECL_VIRTUAL_P (expr), 1); bp_pack_value (bp, DECL_IGNORED_P (expr), 1); @@ -317,10 +327,18 @@ pack_ts_function_decl_value_fields (struct bitpack_d *bp, tree expr) static void pack_ts_type_common_value_fields (struct bitpack_d *bp, tree expr) { + /* For offloading, avoid streaming out TYPE_MODE for aggregate type since + it may be host-specific. For eg, aarch64 uses OImode for ARRAY_TYPE + whose size is 256-bits, which is not representable on accelerator. + Instead stream out VOIDmode, and while streaming-in, recompute + appropriate TYPE_MODE for accelerator. */ + if (lto_stream_offload_p && AGGREGATE_TYPE_P (expr)) + bp_pack_machine_mode (bp, VOIDmode); /* for VECTOR_TYPE, TYPE_MODE reevaluates the mode using target_flags not necessary valid in a global context. Use the raw value previously set by layout_type. */ - bp_pack_machine_mode (bp, TYPE_MODE_RAW (expr)); + else + bp_pack_machine_mode (bp, TYPE_MODE_RAW (expr)); /* TYPE_NO_FORCE_BLK is private to stor-layout and need no streaming. */ bp_pack_value (bp, TYPE_PACKED (expr), 1);