From patchwork Wed Aug 16 15:34:55 2017 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Luc Van Oostenryck X-Patchwork-Id: 9904017 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork.web.codeaurora.org (Postfix) with ESMTP id 148B660231 for ; Wed, 16 Aug 2017 15:36:03 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 05BF8286BC for ; Wed, 16 Aug 2017 15:36:03 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id EECCD28A0A; Wed, 16 Aug 2017 15:36:02 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-6.3 required=2.0 tests=BAYES_00, DKIM_ADSP_CUSTOM_MED, DKIM_SIGNED, FREEMAIL_FROM, RCVD_IN_DNSWL_HI, RCVD_IN_SORBS_SPAM, T_DKIM_INVALID autolearn=ham version=3.3.1 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 45001286BC for ; Wed, 16 Aug 2017 15:36:02 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751471AbdHPPgC (ORCPT ); Wed, 16 Aug 2017 11:36:02 -0400 Received: from mail-wr0-f194.google.com ([209.85.128.194]:35847 "EHLO mail-wr0-f194.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751461AbdHPPgA (ORCPT ); Wed, 16 Aug 2017 11:36:00 -0400 Received: by mail-wr0-f194.google.com with SMTP id y67so3695935wrb.3 for ; Wed, 16 Aug 2017 08:35:59 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=from:to:cc:subject:date:message-id:in-reply-to:references; bh=Ko2cS8F/Eo+qZ+JIWz7LMeftVLljU2hOVwkixz+7nqI=; b=uNwNxCtSNed0F0DjPeunh5t+RX6YANwZHNwMmMjESqk6r4bf5f9/OxGfUzYtSvHVw6 NhXHJEfLN2GD4DupRyT/NGZRf4vZCjkRMsEUzjUB9TpCQDcXvTgrHCK8kK60GHkWV7bW sr7RwPzYw/Br8+QH3GRPQHyi992+Vp1GumhIRLt1osZIrZcjg7G7UHGA8ycI20S76Mcr DJyqne7QvFATbTafmI4PKb0wZ2OCW9XnJKvhzW8GquuX+ex6OuWhOZIwaPdEJzYixwWZ sQq2729WMdRlcjw0T7nmMCJRewiO7r6hOBkX8r8E3G/3iSVfFWPbhbgZd3vnTDlxam9o /kKw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references; bh=Ko2cS8F/Eo+qZ+JIWz7LMeftVLljU2hOVwkixz+7nqI=; b=CECo7A2Er/ReKXwmNeTntFbKof2dTOQcfTGDFgkbmcHZH0peDhgCjrS7SaCf1Bty9d WzYTUP279QQWlTvevnyKvXD6BGV+onb8kFER4HB/m5SkyKZi8Z8E4pqvIk5Zv25eNgyQ KP4hq1OasUH2j/Q7zFdnxo5QPH5fvos75hF6bY8bcLEVjG1NTcIQR3IXz9kaXYkJRz8E yxY9mmOTaHYIBrOhdSjgGoi1PCeGNcrhb/xNWvXwdKh7oXcw25EuMxlQ7GBZaED3mMss R4GvKLpRZdCwshkUHr+Q2L6xZzLWVch/CC7LafJvEnKfL8cWR8x+uaDFOPw2t1++LBUE YCpw== X-Gm-Message-State: AHYfb5jC1lr2JLI0FHv0trMtkUNtthpcAgId/a+l/sUByJx7HJ+F5Ora Y9cBkJSqq3t0exKpr6s= X-Received: by 10.80.164.18 with SMTP id u18mr2318093edb.250.1502897758698; Wed, 16 Aug 2017 08:35:58 -0700 (PDT) Received: from localhost.localdomain ([2a02:a03f:4076:600:895a:bb88:13f:9772]) by smtp.gmail.com with ESMTPSA id y19sm690635edi.6.2017.08.16.08.35.57 (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Wed, 16 Aug 2017 08:35:58 -0700 (PDT) From: Luc Van Oostenryck To: linux-sparse@vger.kernel.org Cc: Linus Torvalds , Christopher Li , Luc Van Oostenryck Subject: [PATCH 29/29] sssa: remove now unneeded simplify_one_symbol() Date: Wed, 16 Aug 2017 17:34:55 +0200 Message-Id: <20170816153455.97693-30-luc.vanoostenryck@gmail.com> X-Mailer: git-send-email 2.14.0 In-Reply-To: <20170816153455.97693-1-luc.vanoostenryck@gmail.com> References: <20170816153455.97693-1-luc.vanoostenryck@gmail.com> Sender: linux-sparse-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-sparse@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP Now that this function is not called anymore, we can remove the associated code. Signed-off-by: Luc Van Oostenryck --- flow.c | 324 ----------------------------------------------------------------- flow.h | 1 - 2 files changed, 325 deletions(-) diff --git a/flow.c b/flow.c index 78dd6b3a5..58ff24d23 100644 --- a/flow.c +++ b/flow.c @@ -362,66 +362,6 @@ int dominates(pseudo_t pseudo, struct instruction *insn, struct instruction *dom return 1; } -static int phisrc_in_bb(struct pseudo_list *list, struct basic_block *bb) -{ - pseudo_t p; - FOR_EACH_PTR(list, p) { - if (p->def->bb == bb) - return 1; - } END_FOR_EACH_PTR(p); - - return 0; -} - -static int find_dominating_parents(pseudo_t pseudo, struct instruction *insn, - struct basic_block *bb, unsigned long generation, struct pseudo_list **dominators, - int local) -{ - struct basic_block *parent; - - if (!bb->parents) - return !!local; - - FOR_EACH_PTR(bb->parents, parent) { - struct instruction *one; - struct instruction *br; - pseudo_t phi; - - FOR_EACH_PTR_REVERSE(parent->insns, one) { - int dominance; - if (one == insn) - goto no_dominance; - dominance = dominates(pseudo, insn, one, local); - if (dominance < 0) { - if (one->opcode == OP_LOAD) - continue; - return 0; - } - if (!dominance) - continue; - goto found_dominator; - } END_FOR_EACH_PTR_REVERSE(one); -no_dominance: - if (parent->generation == generation) - continue; - parent->generation = generation; - - if (!find_dominating_parents(pseudo, insn, parent, generation, dominators, local)) - return 0; - continue; - -found_dominator: - if (dominators && phisrc_in_bb(*dominators, parent)) - continue; - br = delete_last_instruction(&parent->insns); - phi = alloc_phi(parent, one->target, one->type); - phi->ident = phi->ident ? : pseudo->ident; - add_instruction(&parent->insns, br); - use_pseudo(insn, phi, add_pseudo(dominators, phi)); - } END_FOR_EACH_PTR(parent); - return 1; -} - /* * We should probably sort the phi list just to make it easier to compare * later for equality. @@ -460,178 +400,6 @@ complex_phi: insn->phi_list = dominators; } -static int find_dominating_stores(pseudo_t pseudo, struct instruction *insn, - unsigned long generation, int local) -{ - struct basic_block *bb = insn->bb; - struct instruction *one, *dom = NULL; - struct pseudo_list *dominators; - int partial; - - /* Unreachable load? Undo it */ - if (!bb) { - insn->opcode = OP_LNOP; - return 1; - } - - partial = 0; - FOR_EACH_PTR(bb->insns, one) { - int dominance; - if (one == insn) - goto found; - dominance = dominates(pseudo, insn, one, local); - if (dominance < 0) { - /* Ignore partial load dominators */ - if (one->opcode == OP_LOAD) - continue; - dom = NULL; - partial = 1; - continue; - } - if (!dominance) - continue; - dom = one; - partial = 0; - } END_FOR_EACH_PTR(one); - /* Whaa? */ - warning(pseudo->sym->pos, "unable to find symbol read"); - return 0; -found: - if (partial) - return 0; - - if (dom) { - convert_load_instruction(insn, dom->target); - return 1; - } - - /* OK, go find the parents */ - bb->generation = generation; - - dominators = NULL; - if (!find_dominating_parents(pseudo, insn, bb, generation, &dominators, local)) - return 0; - - /* This happens with initial assignments to structures etc.. */ - if (!dominators) { - if (!local) - return 0; - check_access(insn); - convert_load_instruction(insn, value_pseudo(0)); - return 1; - } - - /* - * If we find just one dominating instruction, we - * can turn it into a direct thing. Otherwise we'll - * have to turn the load into a phi-node of the - * dominators. - */ - rewrite_load_instruction(insn, dominators); - return 1; -} - -static void kill_store(struct instruction *insn) -{ - if (insn) { - insn->bb = NULL; - insn->opcode = OP_SNOP; - kill_use(&insn->target); - } -} - -/* Kill a pseudo that is dead on exit from the bb */ -static void kill_dead_stores(pseudo_t pseudo, unsigned long generation, struct basic_block *bb, int local) -{ - struct instruction *insn; - struct basic_block *parent; - - if (bb->generation == generation) - return; - bb->generation = generation; - FOR_EACH_PTR_REVERSE(bb->insns, insn) { - int opcode = insn->opcode; - - if (opcode != OP_LOAD && opcode != OP_STORE) { - if (local) - continue; - if (opcode == OP_CALL) - return; - continue; - } - if (insn->src == pseudo) { - if (opcode == OP_LOAD) - return; - kill_store(insn); - continue; - } - if (local) - continue; - if (insn->src->type != PSEUDO_SYM) - return; - } END_FOR_EACH_PTR_REVERSE(insn); - - FOR_EACH_PTR(bb->parents, parent) { - struct basic_block *child; - FOR_EACH_PTR(parent->children, child) { - if (child && child != bb) - return; - } END_FOR_EACH_PTR(child); - kill_dead_stores(pseudo, generation, parent, local); - } END_FOR_EACH_PTR(parent); -} - -/* - * This should see if the "insn" trivially dominates some previous store, and kill the - * store if unnecessary. - */ -static void kill_dominated_stores(pseudo_t pseudo, struct instruction *insn, - unsigned long generation, struct basic_block *bb, int local, int found) -{ - struct instruction *one; - struct basic_block *parent; - - /* Unreachable store? Undo it */ - if (!bb) { - kill_store(insn); - return; - } - if (bb->generation == generation) - return; - bb->generation = generation; - FOR_EACH_PTR_REVERSE(bb->insns, one) { - int dominance; - if (!found) { - if (one != insn) - continue; - found = 1; - continue; - } - dominance = dominates(pseudo, insn, one, local); - if (!dominance) - continue; - if (dominance < 0) - return; - if (one->opcode == OP_LOAD) - return; - kill_store(one); - } END_FOR_EACH_PTR_REVERSE(one); - - if (!found) { - warning(bb->pos, "Unable to find instruction"); - return; - } - - FOR_EACH_PTR(bb->parents, parent) { - struct basic_block *child; - FOR_EACH_PTR(parent->children, child) { - if (child && child != bb) - return; - } END_FOR_EACH_PTR(child); - kill_dominated_stores(pseudo, insn, generation, parent, local, found); - } END_FOR_EACH_PTR(parent); -} - void check_access(struct instruction *insn) { pseudo_t pseudo = insn->src; @@ -648,98 +416,6 @@ void check_access(struct instruction *insn) } } -static void simplify_one_symbol(struct entrypoint *ep, struct symbol *sym) -{ - pseudo_t pseudo; - struct pseudo_user *pu; - unsigned long mod; - int all; - - /* Never used as a symbol? */ - pseudo = sym->pseudo; - if (!pseudo) - return; - - /* We don't do coverage analysis of volatiles.. */ - if (sym->ctype.modifiers & MOD_VOLATILE) - return; - - /* ..and symbols with external visibility need more care */ - mod = sym->ctype.modifiers & (MOD_NONLOCAL | MOD_STATIC | MOD_ADDRESSABLE); - if (mod) - goto external_visibility; - - FOR_EACH_PTR(pseudo->users, pu) { - /* We know that the symbol-pseudo use is the "src" in the instruction */ - struct instruction *insn = pu->insn; - - switch (insn->opcode) { - case OP_STORE: - break; - case OP_LOAD: - break; - case OP_SYMADDR: - if (!insn->bb) - continue; - mod |= MOD_ADDRESSABLE; - goto external_visibility; - case OP_NOP: - case OP_SNOP: - case OP_LNOP: - case OP_PHI: - continue; - default: - warning(sym->pos, "symbol '%s' pseudo used in unexpected way", show_ident(sym->ident)); - } - } END_FOR_EACH_PTR(pu); - -external_visibility: - all = 1; - FOR_EACH_PTR_REVERSE(pseudo->users, pu) { - struct instruction *insn = pu->insn; - if (insn->opcode == OP_LOAD) - all &= find_dominating_stores(pseudo, insn, ++bb_generation, !mod); - } END_FOR_EACH_PTR_REVERSE(pu); - - /* If we converted all the loads, remove the stores. They are dead */ - if (all && !mod) { - FOR_EACH_PTR(pseudo->users, pu) { - struct instruction *insn = pu->insn; - if (insn->opcode == OP_STORE) - kill_store(insn); - } END_FOR_EACH_PTR(pu); - } else { - /* - * If we couldn't take the shortcut, see if we can at least kill some - * of them.. - */ - FOR_EACH_PTR(pseudo->users, pu) { - struct instruction *insn = pu->insn; - if (insn->opcode == OP_STORE) - kill_dominated_stores(pseudo, insn, ++bb_generation, insn->bb, !mod, 0); - } END_FOR_EACH_PTR(pu); - - if (!(mod & (MOD_NONLOCAL | MOD_STATIC))) { - struct basic_block *bb; - FOR_EACH_PTR(ep->bbs, bb) { - if (!bb->children) - kill_dead_stores(pseudo, ++bb_generation, bb, !mod); - } END_FOR_EACH_PTR(bb); - } - } - - return; -} - -void simplify_symbol_usage(struct entrypoint *ep) -{ - pseudo_t pseudo; - - FOR_EACH_PTR(ep->accesses, pseudo) { - simplify_one_symbol(ep, pseudo->sym); - } END_FOR_EACH_PTR(pseudo); -} - static void mark_bb_reachable(struct basic_block *bb, unsigned long generation) { struct basic_block *child; diff --git a/flow.h b/flow.h index 3133245e5..ecacd42e1 100644 --- a/flow.h +++ b/flow.h @@ -14,7 +14,6 @@ struct instruction; extern int simplify_flow(struct entrypoint *ep); -extern void simplify_symbol_usage(struct entrypoint *ep); extern void simplify_memops(struct entrypoint *ep); extern void pack_basic_blocks(struct entrypoint *ep);