From 52366356fe7b638f66c4011b8a61fb6c22b08087 Mon Sep 17 00:00:00 2001 From: Richard Biener Date: Mon, 27 Jan 2025 11:28:47 +0100 Subject: middle-end/118643 - ICE with out-of-bound decl access When RTL expansion of an out-of-bound access of a register falls back to a BIT_FIELD_REF we have to ensure that's valid. The following avoids negative offsets by expanding through a stack temporary. PR middle-end/118643 * expr.cc (expand_expr_real_1): Avoid falling back to BIT_FIELD_REF expansion for negative offset. * gcc.dg/pr118643.c: New testcase. --- gcc/expr.cc | 7 ++++--- 1 file changed, 4 insertions(+), 3 deletions(-) (limited to 'gcc/expr.cc') diff --git a/gcc/expr.cc b/gcc/expr.cc index a310b2d..a06411e 100644 --- a/gcc/expr.cc +++ b/gcc/expr.cc @@ -11796,13 +11796,14 @@ expand_expr_real_1 (tree exp, rtx target, machine_mode tmode, && known_eq (GET_MODE_BITSIZE (DECL_MODE (base)), type_size)) return expand_expr (build1 (VIEW_CONVERT_EXPR, type, base), target, tmode, modifier); - if (TYPE_MODE (type) == BLKmode) + if (TYPE_MODE (type) == BLKmode || maybe_lt (offset, 0)) { temp = assign_stack_temp (DECL_MODE (base), GET_MODE_SIZE (DECL_MODE (base))); store_expr (base, temp, 0, false, false); - temp = adjust_address (temp, BLKmode, offset); - set_mem_size (temp, int_size_in_bytes (type)); + temp = adjust_address (temp, TYPE_MODE (type), offset); + if (TYPE_MODE (type) == BLKmode) + set_mem_size (temp, int_size_in_bytes (type)); return temp; } exp = build3 (BIT_FIELD_REF, type, base, TYPE_SIZE (type), -- cgit v1.1