{"id":811595,"url":"http://patchwork.ozlabs.org/api/1.2/patches/811595/?format=json","web_url":"http://patchwork.ozlabs.org/project/gcc/patch/20170908133620.GA100539@adacore.com/","project":{"id":17,"url":"http://patchwork.ozlabs.org/api/1.2/projects/17/?format=json","name":"GNU Compiler Collection","link_name":"gcc","list_id":"gcc-patches.gcc.gnu.org","list_email":"gcc-patches@gcc.gnu.org","web_url":null,"scm_url":null,"webscm_url":null,"list_archive_url":"","list_archive_url_format":"","commit_url_format":""},"msgid":"<20170908133620.GA100539@adacore.com>","list_archive_url":null,"date":"2017-09-08T13:36:20","name":"[Ada] Extend efficient array reset to all elementary types","commit_ref":null,"pull_url":null,"state":"new","archived":false,"hash":"197053f307b5583e1b17a2b9bbd77de47269a268","submitter":{"id":4418,"url":"http://patchwork.ozlabs.org/api/1.2/people/4418/?format=json","name":"Arnaud Charlet","email":"charlet@adacore.com"},"delegate":null,"mbox":"http://patchwork.ozlabs.org/project/gcc/patch/20170908133620.GA100539@adacore.com/mbox/","series":[{"id":2214,"url":"http://patchwork.ozlabs.org/api/1.2/series/2214/?format=json","web_url":"http://patchwork.ozlabs.org/project/gcc/list/?series=2214","date":"2017-09-08T13:36:20","name":"[Ada] Extend efficient array reset to all elementary types","version":1,"mbox":"http://patchwork.ozlabs.org/series/2214/mbox/"}],"comments":"http://patchwork.ozlabs.org/api/patches/811595/comments/","check":"pending","checks":"http://patchwork.ozlabs.org/api/patches/811595/checks/","tags":{},"related":[],"headers":{"Return-Path":"","X-Original-To":"incoming@patchwork.ozlabs.org","Delivered-To":["patchwork-incoming@bilbo.ozlabs.org","mailing list gcc-patches@gcc.gnu.org"],"Authentication-Results":["ozlabs.org;\n\tspf=pass (mailfrom) smtp.mailfrom=gcc.gnu.org\n\t(client-ip=209.132.180.131; helo=sourceware.org;\n\tenvelope-from=gcc-patches-return-461728-incoming=patchwork.ozlabs.org@gcc.gnu.org;\n\treceiver=)","ozlabs.org; dkim=pass (1024-bit key;\n\tunprotected) header.d=gcc.gnu.org header.i=@gcc.gnu.org\n\theader.b=\"v2BkCyUF\"; dkim-atps=neutral","sourceware.org; auth=none"],"Received":["from sourceware.org (server1.sourceware.org [209.132.180.131])\n\t(using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256\n\tbits)) (No client certificate requested)\n\tby ozlabs.org (Postfix) with ESMTPS id 3xpddX66jfz9s7p\n\tfor ;\n\tFri, 8 Sep 2017 23:36:32 +1000 (AEST)","(qmail 44283 invoked by alias); 8 Sep 2017 13:36:23 -0000","(qmail 44052 invoked by uid 89); 8 Sep 2017 13:36:23 -0000","from rock.gnat.com (HELO rock.gnat.com) (205.232.38.15) by\n\tsourceware.org (qpsmtpd/0.93/v0.84-503-g423c35a) with ESMTP;\n\tFri, 08 Sep 2017 13:36:21 +0000","from localhost (localhost.localdomain [127.0.0.1])\tby\n\tfiltered-rock.gnat.com (Postfix) with ESMTP id 80F275628A;\n\tFri, 8 Sep 2017 09:36:20 -0400 (EDT)","from rock.gnat.com ([127.0.0.1])\tby localhost (rock.gnat.com\n\t[127.0.0.1]) (amavisd-new, port 10024)\twith LMTP id\n\tVmPmCWbg0mG4; 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run by ezmlm","Precedence":"bulk","List-Id":"","List-Unsubscribe":"","List-Archive":"","List-Post":"","List-Help":"","Sender":"gcc-patches-owner@gcc.gnu.org","X-Virus-Found":"No","X-Spam-SWARE-Status":"No, score=-10.5 required=5.0 tests=AWL, BAYES_00,\n\tGIT_PATCH_2, GIT_PATCH_3, KAM_ASCII_DIVIDERS,\n\tRCVD_IN_DNSWL_NONE,\n\tSPF_PASS autolearn=ham version=3.3.2 spammy=","X-HELO":"rock.gnat.com","Date":"Fri, 8 Sep 2017 09:36:20 -0400","From":"Arnaud Charlet ","To":"gcc-patches@gcc.gnu.org","Cc":"Eric Botcazou ","Subject":"[Ada] Extend efficient array reset to all elementary types","Message-ID":"<20170908133620.GA100539@adacore.com>","MIME-Version":"1.0","Content-Type":"multipart/mixed; boundary=\"EVF5PPMfhYS0aIcm\"","Content-Disposition":"inline","User-Agent":"Mutt/1.5.23 (2014-03-12)"},"content":"This change extends the efficient handling of an array reset to 0 by means\nof an aggregate with a single Others choice from a discrete component type\nto any elementary type.\n\nThe 3 instances of the Reset procedure below must invoke memset:\n\nwith G;\n\npackage P is\n\n subtype Index is Positive range 1 .. 128;\n\n type Ptr is access all Integer;\n\n package My_G_I is new G (Index, Integer, 0);\n\n package My_G_F is new G (Index, Float, 0.0);\n\n package My_G_P is new G (Index, Ptr, null);\n\nend P;\n\ngeneric\n\n type Header_Num is range <>;\n\n type Element is private;\n\n Null_Element : Element;\n\npackage G is\n\n procedure Reset;\n\nend G;\n\npackage body G is\n\n Table : array (Header_Num) of Element;\n\n procedure Reset is\n begin\n Table := (others => Null_Element);\n end;\n \nend G;\n\nTested on x86_64-pc-linux-gnu, committed on trunk\n\n2017-09-08 Eric Botcazou \n\n\t* exp_aggr.adb: Add with & use clause for Urealp.\n\t(Aggr_Assignment_OK_For_Backend): Accept (almost all)\n\telementary types instead of just discrete types.\n\t* sem_eval.adb (Expr_Value): Deal with N_Null for access types.\n\t* gcc-interface/trans.c (gnat_to_gnu) :\n\tBe prepared for the FP zero value in the memset case. Add small\n\tguard.","diff":"Index: exp_aggr.adb\n===================================================================\n--- exp_aggr.adb\t(revision 251893)\n+++ exp_aggr.adb\t(working copy)\n@@ -61,6 +61,7 @@\n with Stringt; use Stringt;\n with Tbuild; use Tbuild;\n with Uintp; use Uintp;\n+with Urealp; use Urealp;\n \n package body Exp_Aggr is\n \n@@ -4894,7 +4895,7 @@\n -- 4. The array type has no null ranges (the purpose of this is to\n -- avoid a bogus warning for an out-of-range value).\n \n- -- 5. The component type is discrete\n+ -- 5. The component type is elementary\n \n -- 6. The component size is Storage_Unit or the value is of the form\n -- M * (1 + A**1 + A**2 + .. A**(K-1)) where A = 2**(Storage_Unit)\n@@ -4970,7 +4971,13 @@\n return False;\n end if;\n \n- if not Is_Discrete_Type (Ctyp) then\n+ -- All elementary types are supported except for fat pointers\n+ -- because they are not really elementary for the backend.\n+\n+ if not Is_Elementary_Type (Ctyp)\n+ or else (Is_Access_Type (Ctyp)\n+ and then Esize (Ctyp) /= System_Address_Size)\n+ then\n return False;\n end if;\n \n@@ -4990,6 +4997,14 @@\n return False;\n end if;\n \n+ -- The only supported value for floating point is 0.0\n+\n+ if Is_Floating_Point_Type (Ctyp) then\n+ return Expr_Value_R (Expr) = Ureal_0;\n+ end if;\n+\n+ -- For other types, we can look into the value as an integer\n+\n Value := Expr_Value (Expr);\n \n if Has_Biased_Representation (Ctyp) then\nIndex: sem_eval.adb\n===================================================================\n--- sem_eval.adb\t(revision 251892)\n+++ sem_eval.adb\t(working copy)\n@@ -4199,6 +4199,12 @@\n pragma Assert (Is_Fixed_Point_Type (Underlying_Type (Etype (N))));\n Val := Corresponding_Integer_Value (N);\n \n+ -- The NULL access value\n+\n+ elsif Kind = N_Null then\n+ pragma Assert (Is_Access_Type (Underlying_Type (Etype (N))));\n+ Val := Uint_0;\n+\n -- Otherwise must be character literal\n \n else\nIndex: gcc-interface/trans.c\n===================================================================\n--- gcc-interface/trans.c\t(revision 251892)\n+++ gcc-interface/trans.c\t(working copy)\n@@ -7037,14 +7037,17 @@\n \t /* Or else, use memset when the conditions are met. */\n \t else if (use_memset_p)\n \t {\n-\t tree value = fold_convert (integer_type_node, gnu_rhs);\n+\t tree value\n+\t\t= real_zerop (gnu_rhs)\n+\t\t ? integer_zero_node\n+\t\t : fold_convert (integer_type_node, gnu_rhs);\n \t tree to = gnu_lhs;\n \t tree type = TREE_TYPE (to);\n \t tree size\n \t = SUBSTITUTE_PLACEHOLDER_IN_EXPR (TYPE_SIZE_UNIT (type), to);\n \t tree to_ptr = build_fold_addr_expr (to);\n \t tree t = builtin_decl_explicit (BUILT_IN_MEMSET);\n-\t if (TREE_CODE (value) == INTEGER_CST)\n+\t if (TREE_CODE (value) == INTEGER_CST && !integer_zerop (value))\n \t\t{\n \t\t tree mask\n \t\t = build_int_cst (integer_type_node,\n","prefixes":["Ada"]}