From patchwork Thu May 13 22:06:53 2021
Content-Type: text/plain; charset="utf-8"
MIME-Version: 1.0
Content-Transfer-Encoding: 8bit
X-Patchwork-Submitter: Tobias Burnus
X-Patchwork-Id: 1478216
Return-Path:
X-Original-To: incoming@patchwork.ozlabs.org
Delivered-To: patchwork-incoming@bilbo.ozlabs.org
Authentication-Results: ozlabs.org;
spf=pass (sender SPF authorized) smtp.mailfrom=gcc.gnu.org
(client-ip=8.43.85.97; helo=sourceware.org;
envelope-from=gcc-patches-bounces@gcc.gnu.org; receiver=)
Received: from sourceware.org (server2.sourceware.org [8.43.85.97])
(using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits)
key-exchange X25519 server-signature RSA-PSS (4096 bits) server-digest
SHA256)
(No client certificate requested)
by ozlabs.org (Postfix) with ESMTPS id 4Fh5Nr1q6Zz9sW1
for ; Fri, 14 May 2021 08:07:06 +1000 (AEST)
Received: from server2.sourceware.org (localhost [IPv6:::1])
by sourceware.org (Postfix) with ESMTP id A26EB3847807;
Thu, 13 May 2021 22:07:03 +0000 (GMT)
X-Original-To: gcc-patches@gcc.gnu.org
Delivered-To: gcc-patches@gcc.gnu.org
Received: from esa2.mentor.iphmx.com (esa2.mentor.iphmx.com [68.232.141.98])
by sourceware.org (Postfix) with ESMTPS id E2192384802D
for ; Thu, 13 May 2021 22:07:00 +0000 (GMT)
DMARC-Filter: OpenDMARC Filter v1.3.2 sourceware.org E2192384802D
Authentication-Results: sourceware.org; dmarc=none (p=none dis=none)
header.from=codesourcery.com
Authentication-Results: sourceware.org;
spf=pass smtp.mailfrom=Tobias_Burnus@mentor.com
IronPort-SDR:
GvcmHbZV7Xb9R/BzzDQFHLUvdroelm0uEs2tSdW+eBDlmOJb4zfz6EP1DqVAwpgYMDQJNFld5y
7R2vRKFcXwF6+QO2AnzwAzImX51Z+N8rsrdwr/82IxXdA6vjSYLN/EE5TeeUw0GMljVxqzYvcA
oU1vNjgvqxhD2Patdyq+z1ClK9vntwGdqfUlR9xChPw4+b4TYnrtIaif0AzjeGLWkiCMdtEDhy
NP2a+O7SXwYAyGFMovJGa0iVXuDYb+/xVIkrKK6F4zFAGmmR50m1fITP6PvkniftBeYtC3rdSC
QZ0=
X-IronPort-AV: E=Sophos;i="5.82,296,1613462400";
d="diff'?scan'208";a="61184888"
Received: from orw-gwy-02-in.mentorg.com ([192.94.38.167])
by esa2.mentor.iphmx.com with ESMTP; 13 May 2021 14:06:59 -0800
IronPort-SDR:
Xro+jsZFOdZMa6ZuXpe6OMXMnVA+IDynXCwW7teAwa1V9ELoQM8RLnMPdw8+H01lQU/SfiuvU/
FwevvGhCxb7n/bHfVo0zsf9Xwrz/EIfGaLxS0iEPeU27kWR+U//nj4JQmhVVXiQEB7zaHdRsLg
OBfTVX6Oan6vlManqSm3i5mWlkw1nmQP2oHmdPMyUh+Tn1DSWbN1aSWEbo3RvEBlT30/s1jlGv
/auH9g4YOOfiQkt0xJBfAZ8gsPp1M/4w51HKx0wpZYkr1sHc0CLVS1h5cxycck80xyem1E5FMS
ObM=
To: gcc-patches , Gerald Pfeifer
, Tom de Vries
From: Tobias Burnus
Subject: [wwwdocs, patch] gcc-12/changes.html: Document -mptx for nvptx
Message-ID: <0b73f43a-1bc2-116b-9fcf-7eb356f5d9d3@codesourcery.com>
Date: Fri, 14 May 2021 00:06:53 +0200
User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:78.0) Gecko/20100101
Thunderbird/78.10.1
MIME-Version: 1.0
Content-Language: en-US
X-Originating-IP: [137.202.0.90]
X-ClientProxiedBy: svr-ies-mbx-02.mgc.mentorg.com (139.181.222.2) To
svr-ies-mbx-01.mgc.mentorg.com (139.181.222.1)
X-Spam-Status: No, score=-11.9 required=5.0 tests=BAYES_00, GIT_PATCH_0,
HEADER_FROM_DIFFERENT_DOMAINS, KAM_DMARC_STATUS, KAM_SHORT,
RCVD_IN_DNSWL_NONE,
SPF_HELO_PASS, SPF_PASS, TXREP autolearn=ham autolearn_force=no version=3.4.2
X-Spam-Checker-Version: SpamAssassin 3.4.2 (2018-09-13) on
server2.sourceware.org
X-BeenThere: gcc-patches@gcc.gnu.org
X-Mailman-Version: 2.1.29
Precedence: list
List-Id: Gcc-patches mailing list
List-Unsubscribe: ,
List-Archive:
List-Post:
List-Help:
List-Subscribe: ,
Errors-To: gcc-patches-bounces@gcc.gnu.org
Sender: "Gcc-patches"
Document this new flag, added in
https://gcc.gnu.org/g:2a1586401a21dcd43e0f904bb6eec26c8b2f366b
+ https://gcc.gnu.org/onlinedocs/gcc/Nvidia-PTX-Options.html#index-mptx
Any wording suggestions?
Tobias
PS: Some background remarks:
(PTX ISA 3.1 is supported since NVidia's CUDA 5 while 6.3 is supported since
CUDA 10.0 - and adds very useful new features; current is PTX ISA 7.3
(CUDA 11.3),* but on the PTX side, 6.3 adds a lot, >6.3 only few features,
we still may want to support sometime in the future.)
(The new flag paves the way for additional -misa= flags
(i.e. newer hardware, relevant for enabling ptx instructions which only
newer GPUs support) and newer GPU-hardware-independent PTX ISA features;
hence, either permitting better code generation or for be used to fix bugs.
While this will change during GCC 12, currently, the generated code is
effectively the same with either -mptx= value.)
(Regarding the produced instructions, the installed CUDA will JIT
(and then cache) the GCC-generated nvptx in the binary at startup,
optimizing for the available hardware - i.e. the chosen -mptx and
available -misa do not restrict the hardware ability, just that
PTX instructions which is only available in newer PTX / for newer
hardware may not be generated.)
(* Cf. https://docs.nvidia.com/cuda/parallel-thread-execution/index.html#release-notes__ptx-release-history )
-----------------
Mentor Graphics (Deutschland) GmbH, Arnulfstrasse 201, 80634 München Registergericht München HRB 106955, Geschäftsführer: Thomas Heurung, Frank Thürauf
gcc-12/changes.html: Document -mptx for nvptx
* htdocs/gcc-12/changes.html (nvptx): Document new -mptx flag.
diff --git a/htdocs/gcc-12/changes.html b/htdocs/gcc-12/changes.html
index 23f71411..6541cf4e 100644
--- a/htdocs/gcc-12/changes.html
+++ b/htdocs/gcc-12/changes.html
@@ -101,8 +101,13 @@ a work-in-progress.
-
-
+NVPTX
+
+ - The
-mptx
flag has been added to specify the PTX ISA version
+ for the generated code; permitted values are 3.1
+ (default and as used previous GCC versions) and 6.3
.
+
+