From d05d755107df11e675a57ac4371fd0031c7d68a4 Mon Sep 17 00:00:00 2001 From: Richard Sandiford Date: Wed, 20 Dec 2017 12:53:23 +0000 Subject: poly_int: MEM_OFFSET and MEM_SIZE This patch changes the MEM_OFFSET and MEM_SIZE memory attributes from HOST_WIDE_INT to poly_int64. Most of it is mechanical, but there is one nonbovious change in widen_memory_access. Previously the main while loop broke with: /* Similarly for the decl. */ else if (DECL_P (attrs.expr) && DECL_SIZE_UNIT (attrs.expr) && TREE_CODE (DECL_SIZE_UNIT (attrs.expr)) == INTEGER_CST && compare_tree_int (DECL_SIZE_UNIT (attrs.expr), size) >= 0 && (! attrs.offset_known_p || attrs.offset >= 0)) break; but it seemed wrong to optimistically assume the best case when the offset isn't known (and thus might be negative). As it happens, the "! attrs.offset_known_p" condition was always false, because we'd already nullified attrs.expr in that case: /* If we don't know what offset we were at within the expression, then we can't know if we've overstepped the bounds. */ if (! attrs.offset_known_p) attrs.expr = NULL_TREE; The patch therefore drops "! attrs.offset_known_p ||" when converting the offset check to the may/must interface. 2017-12-20 Richard Sandiford Alan Hayward David Sherwood gcc/ * rtl.h (mem_attrs): Add a default constructor. Change size and offset from HOST_WIDE_INT to poly_int64. * emit-rtl.h (set_mem_offset, set_mem_size, adjust_address_1) (adjust_automodify_address_1, set_mem_attributes_minus_bitpos) (widen_memory_access): Take the sizes and offsets as poly_int64s rather than HOST_WIDE_INTs. * alias.c (ao_ref_from_mem): Handle the new form of MEM_OFFSET. (offset_overlap_p): Take poly_int64s rather than HOST_WIDE_INTs and ints. (adjust_offset_for_component_ref): Change the offset from a HOST_WIDE_INT to a poly_int64. (nonoverlapping_memrefs_p): Track polynomial offsets and sizes. * cfgcleanup.c (merge_memattrs): Update after mem_attrs changes. * dce.c (find_call_stack_args): Likewise. * dse.c (record_store): Likewise. * dwarf2out.c (tls_mem_loc_descriptor, dw_sra_loc_expr): Likewise. * print-rtl.c (rtx_writer::print_rtx): Likewise. * read-rtl-function.c (test_loading_mem): Likewise. * rtlanal.c (may_trap_p_1): Likewise. * simplify-rtx.c (delegitimize_mem_from_attrs): Likewise. * var-tracking.c (int_mem_offset, track_expr_p): Likewise. * emit-rtl.c (mem_attrs_eq_p, get_mem_align_offset): Likewise. (mem_attrs::mem_attrs): New function. (set_mem_attributes_minus_bitpos): Change bitpos from a HOST_WIDE_INT to poly_int64. (set_mem_alias_set, set_mem_addr_space, set_mem_align, set_mem_expr) (clear_mem_offset, clear_mem_size, change_address) (get_spill_slot_decl, set_mem_attrs_for_spill): Directly initialize mem_attrs. (set_mem_offset, set_mem_size, adjust_address_1) (adjust_automodify_address_1, offset_address, widen_memory_access): Likewise. Take poly_int64s rather than HOST_WIDE_INT. Co-Authored-By: Alan Hayward Co-Authored-By: David Sherwood From-SVN: r255875 --- gcc/dse.c | 8 ++++++-- 1 file changed, 6 insertions(+), 2 deletions(-) (limited to 'gcc/dse.c') diff --git a/gcc/dse.c b/gcc/dse.c index d196b79..3e0a416 100644 --- a/gcc/dse.c +++ b/gcc/dse.c @@ -1365,6 +1365,7 @@ record_store (rtx body, bb_info_t bb_info) /* At this point we know mem is a mem. */ if (GET_MODE (mem) == BLKmode) { + HOST_WIDE_INT const_size; if (GET_CODE (XEXP (mem, 0)) == SCRATCH) { if (dump_file && (dump_flags & TDF_DETAILS)) @@ -1376,8 +1377,11 @@ record_store (rtx body, bb_info_t bb_info) /* Handle (set (mem:BLK (addr) [... S36 ...]) (const_int 0)) as memset (addr, 0, 36); */ else if (!MEM_SIZE_KNOWN_P (mem) - || MEM_SIZE (mem) <= 0 - || MEM_SIZE (mem) > MAX_OFFSET + || maybe_le (MEM_SIZE (mem), 0) + /* This is a limit on the bitmap size, which is only relevant + for constant-sized MEMs. */ + || (MEM_SIZE (mem).is_constant (&const_size) + && const_size > MAX_OFFSET) || GET_CODE (body) != SET || !CONST_INT_P (SET_SRC (body))) { -- cgit v1.1