From mboxrd@z Thu Jan 1 00:00:00 1970 From: Luc Van Oostenryck Subject: [PATCH 2/4] remove bit_size & bit_offset from struct access_data Date: Fri, 7 Apr 2017 01:00:27 +0200 Message-ID: <20170406230029.11384-3-luc.vanoostenryck@gmail.com> References: <20170406230029.11384-1-luc.vanoostenryck@gmail.com> Return-path: Received: from mail-wr0-f193.google.com ([209.85.128.193]:34196 "EHLO mail-wr0-f193.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752226AbdDFXAi (ORCPT ); Thu, 6 Apr 2017 19:00:38 -0400 Received: by mail-wr0-f193.google.com with SMTP id u18so7293259wrc.1 for ; Thu, 06 Apr 2017 16:00:38 -0700 (PDT) In-Reply-To: <20170406230029.11384-1-luc.vanoostenryck@gmail.com> Sender: linux-sparse-owner@vger.kernel.org List-Id: linux-sparse@vger.kernel.org To: linux-sparse@vger.kernel.org Cc: Linus Torvalds , Christopher Li , Luc Van Oostenryck In struct access_data, the fields: 'bit_offset', 'bit_size' and 'alignment' are always the ones corresponding to the 'result_type' and are thus completely redundant. Change this by removing these fields and directly using the info from the 'result_type' field. Note: the motivation for this change is the realization that the initialization of bitfields are buggy because the 'bit_size' is never set for initializers. The bug could be solved by initializing 'bit_size' & 'bit_offset' but it was much simpler (and feel safer) to simply use the values from 'result_type'. Signed-off-by: Luc Van Oostenryck --- linearize.c | 19 +++++++++---------- 1 file changed, 9 insertions(+), 10 deletions(-) diff --git a/linearize.c b/linearize.c index 61c804333..e9610932b 100644 --- a/linearize.c +++ b/linearize.c @@ -844,8 +844,7 @@ struct access_data { struct symbol *source_type; // source ctype pseudo_t address; // pseudo containing address .. pseudo_t origval; // pseudo for original value .. - unsigned int offset, alignment; // byte offset - unsigned int bit_size, bit_offset; // which bits + unsigned int offset; // byte offset struct position pos; }; @@ -898,9 +897,6 @@ static int linearize_address_gen(struct entrypoint *ep, ad->pos = expr->pos; ad->result_type = ctype; ad->source_type = base_type(ctype); - ad->bit_size = ctype->bit_size; - ad->alignment = ctype->ctype.alignment; - ad->bit_offset = ctype->bit_offset; if (expr->type == EXPR_PREOP && expr->op == '*') return linearize_simple_address(ep, expr->unop, ad); @@ -948,9 +944,11 @@ static pseudo_t linearize_store_gen(struct entrypoint *ep, pseudo_t store = value; if (type_size(ad->source_type) != type_size(ad->result_type)) { + struct symbol *ctype = ad->result_type; + unsigned int shift = ctype->bit_offset; + unsigned int size = ctype->bit_size; pseudo_t orig = add_load(ep, ad); - int shift = ad->bit_offset; - unsigned long long mask = (1ULL << ad->bit_size)-1; + unsigned long long mask = (1ULL << size) - 1; if (shift) { store = add_binary_op(ep, ad->source_type, OP_SHL, value, value_pseudo(shift)); @@ -997,14 +995,15 @@ static pseudo_t add_symbol_address(struct entrypoint *ep, struct symbol *sym) static pseudo_t linearize_load_gen(struct entrypoint *ep, struct access_data *ad) { + struct symbol *ctype = ad->result_type; pseudo_t new = add_load(ep, ad); - if (ad->bit_offset) { - pseudo_t shift = value_pseudo(ad->bit_offset); + if (ctype->bit_offset) { + pseudo_t shift = value_pseudo(ctype->bit_offset); pseudo_t newval = add_binary_op(ep, ad->source_type, OP_LSR, new, shift); new = newval; } - if (ad->bit_size != type_size(ad->source_type)) + if (ctype->bit_size != type_size(ad->source_type)) new = cast_pseudo(ep, new, ad->source_type, ad->result_type); return new; } -- 2.12.0