From patchwork Wed Oct 31 13:10:17 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Zong Li X-Patchwork-Id: 29980 Received: (qmail 108744 invoked by alias); 31 Oct 2018 13:12:27 -0000 Mailing-List: contact libc-alpha-help@sourceware.org; run by ezmlm Precedence: bulk List-Id: List-Unsubscribe: List-Subscribe: List-Archive: List-Post: List-Help: , Sender: libc-alpha-owner@sourceware.org Delivered-To: mailing list libc-alpha@sourceware.org Received: (qmail 108625 invoked by uid 89); 31 Oct 2018 13:12:26 -0000 Authentication-Results: sourceware.org; auth=none X-Spam-SWARE-Status: No, score=-25.6 required=5.0 tests=AWL, BAYES_00, FREEMAIL_FROM, GIT_PATCH_0, GIT_PATCH_1, GIT_PATCH_2, GIT_PATCH_3, KAM_NUMSUBJECT, RCVD_IN_DNSWL_NONE, SPF_PASS autolearn=ham version=3.3.2 spammy=H*r:sk:bh10-v6, D*andestech.com, HX-Received:sk:d9-v6mr, HX-Received:b709 X-HELO: mail-pl1-f193.google.com 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=Mauj/yIKP9iaojDHlZWFmAaxYhaGl+QJhC57i7AuxZ4=; b=kMlYKgKIuiftI6SGmvUouJsEFeQ515i8RQpSBialGFsWctuiNzJlTwa+kx+bvZRHN4 efpIWr3mNIBw1f9ykt1feoZtgGYiU0GIwbyP9zsXGua9Lq6a1ya5ZzvVRYQBDphMZw9C 4cZqHsgM/0vRlgX2ZzJiewhl9vvE7hvoy+QW0LU78prfrWLqIqZ3AIySKd+Tm9PmAORv BfU6gVapxbfZW1+/GPcZ+HliGt51aGmeDMCWDRirfMqLBQJ0WkM+SOufsj0cuWiCk83q zEORwwVikAGOH4Z6KfhH15Yj6fg+gG9ofJQqo+4RH3L38ZgNzkP388JuHXzA4V5/FmZX OV/A== Return-Path: From: Zong Li To: joseph@codesourcery.com, palmer@dabbelt.com, jimw@sifive.com, kito@andestech.com, greentime@andestech.com, zong@andestech.com Cc: libc-alpha@sourceware.org, Zong Li Subject: [PATCH v2 1/2] soft-fp: Use temporary variable in FP_FRAC_SUB_3/FP_FRAC_SUB_4 Date: Wed, 31 Oct 2018 21:10:17 +0800 Message-Id: In-Reply-To: References: In FRAC_SUB_3(R, X, Y) and FRAC_SUB_4(R,, X, Y), it reference both the X[N] and X[N] after R[N] have been set. If one of the X and Y is the same address with R, the result of the calculation is wrong, because the value of the original X and Y are overwritten. In glibc, there are two places use FRAC_SUB and occurs the overlap. The first is _FP_DIV_MEAT_N_loop in op-common.h, it uses the source _FP_DIV_MEAT_N_loop_u as the destination. This macro only be used when N is one(_FP_DIV_MEAT_1_loop) and then the _FP_FRAC_SUB_##wc extend to _FP_FRAC_SUB_1 in this macro. so it also work because _FP_FRAC_SUB_1 has no overlap problem in its implementation. The second places is _FP_DIV_MEAT_4_udiv, the original value of X##_f[0] is overwritten before the calculatation. In FRAC_SUB_1 and FRAC_SUB_2, there don't refer the source after destination have been set, so they have no problem. After this modification, we can pass the soft floating testing of glibc testsuites on RV32. * soft-fp/op-4.h (_FP_FRAC_SUB_3, _FP_FRAC_SUB_4): Use temporary variable to avoid overlap arguments. --- ChangeLog | 5 +++++ soft-fp/op-4.h | 63 ++++++++++++++++++++++++++++++++-------------------------- 2 files changed, 40 insertions(+), 28 deletions(-) diff --git a/ChangeLog b/ChangeLog index b798b63..0cced2b 100644 --- a/ChangeLog +++ b/ChangeLog @@ -1,3 +1,8 @@ +2018-10-31 Zong Li + + * soft-fp/op-4.h (_FP_FRAC_SUB_3, _FP_FRAC_SUB_4): Use temporary + variable to avoid overlap arguments. + 2018-10-31 Samuel Thibault * manual/errno.texi (EIEIO): Document how translators should diff --git a/soft-fp/op-4.h b/soft-fp/op-4.h index 01b87d0..b429801 100644 --- a/soft-fp/op-4.h +++ b/soft-fp/op-4.h @@ -696,39 +696,46 @@ #endif #ifndef __FP_FRAC_SUB_3 -# define __FP_FRAC_SUB_3(r2, r1, r0, x2, x1, x0, y2, y1, y0) \ - do \ - { \ - _FP_W_TYPE __FP_FRAC_SUB_3_c1, __FP_FRAC_SUB_3_c2; \ - r0 = x0 - y0; \ - __FP_FRAC_SUB_3_c1 = r0 > x0; \ - r1 = x1 - y1; \ - __FP_FRAC_SUB_3_c2 = r1 > x1; \ - r1 -= __FP_FRAC_SUB_3_c1; \ - __FP_FRAC_SUB_3_c2 |= __FP_FRAC_SUB_3_c1 && (y1 == x1); \ - r2 = x2 - y2 - __FP_FRAC_SUB_3_c2; \ - } \ +# define __FP_FRAC_SUB_3(r2, r1, r0, x2, x1, x0, y2, y1, y0) \ + do \ + { \ + _FP_W_TYPE __FP_FRAC_SUB_3_tmp[2]; \ + _FP_W_TYPE __FP_FRAC_SUB_3_c1, __FP_FRAC_SUB_3_c2; \ + __FP_FRAC_SUB_3_tmp[0] = x0 - y0; \ + __FP_FRAC_SUB_3_c1 = __FP_FRAC_SUB_3_tmp[0] > x0; \ + __FP_FRAC_SUB_3_tmp[1] = x1 - y1; \ + __FP_FRAC_SUB_3_c2 = __FP_FRAC_SUB_3_tmp[1] > x1; \ + __FP_FRAC_SUB_3_tmp[1] -= __FP_FRAC_SUB_3_c1; \ + __FP_FRAC_SUB_3_c2 |= __FP_FRAC_SUB_3_c1 && (y1 == x1); \ + r2 = x2 - y2 - __FP_FRAC_SUB_3_c2; \ + r1 = __FP_FRAC_SUB_3_tmp[1]; \ + r0 = __FP_FRAC_SUB_3_tmp[0]; \ + } \ while (0) #endif #ifndef __FP_FRAC_SUB_4 # define __FP_FRAC_SUB_4(r3, r2, r1, r0, x3, x2, x1, x0, y3, y2, y1, y0) \ - do \ - { \ - _FP_W_TYPE __FP_FRAC_SUB_4_c1, __FP_FRAC_SUB_4_c2; \ - _FP_W_TYPE __FP_FRAC_SUB_4_c3; \ - r0 = x0 - y0; \ - __FP_FRAC_SUB_4_c1 = r0 > x0; \ - r1 = x1 - y1; \ - __FP_FRAC_SUB_4_c2 = r1 > x1; \ - r1 -= __FP_FRAC_SUB_4_c1; \ - __FP_FRAC_SUB_4_c2 |= __FP_FRAC_SUB_4_c1 && (y1 == x1); \ - r2 = x2 - y2; \ - __FP_FRAC_SUB_4_c3 = r2 > x2; \ - r2 -= __FP_FRAC_SUB_4_c2; \ - __FP_FRAC_SUB_4_c3 |= __FP_FRAC_SUB_4_c2 && (y2 == x2); \ - r3 = x3 - y3 - __FP_FRAC_SUB_4_c3; \ - } \ + do \ + { \ + _FP_W_TYPE __FP_FRAC_SUB_4_tmp[3]; \ + _FP_W_TYPE __FP_FRAC_SUB_4_c1, __FP_FRAC_SUB_4_c2; \ + _FP_W_TYPE __FP_FRAC_SUB_4_c3; \ + __FP_FRAC_SUB_4_tmp[0] = x0 - y0; \ + __FP_FRAC_SUB_4_c1 = __FP_FRAC_SUB_4_tmp[0] > x0; \ + __FP_FRAC_SUB_4_tmp[1] = x1 - y1; \ + __FP_FRAC_SUB_4_c2 = __FP_FRAC_SUB_4_tmp[1] > x1; \ + __FP_FRAC_SUB_4_tmp[1] -= __FP_FRAC_SUB_4_c1; \ + __FP_FRAC_SUB_4_c2 |= __FP_FRAC_SUB_4_c1 && (y1 == x1); \ + __FP_FRAC_SUB_4_tmp[2] = x2 - y2; \ + __FP_FRAC_SUB_4_c3 = __FP_FRAC_SUB_4_tmp[2] > x2; \ + __FP_FRAC_SUB_4_tmp[2] -= __FP_FRAC_SUB_4_c2; \ + __FP_FRAC_SUB_4_c3 |= __FP_FRAC_SUB_4_c2 && (y2 == x2); \ + r3 = x3 - y3 - __FP_FRAC_SUB_4_c3; \ + r2 = __FP_FRAC_SUB_4_tmp[2]; \ + r1 = __FP_FRAC_SUB_4_tmp[1]; \ + r0 = __FP_FRAC_SUB_4_tmp[0]; \ + } \ while (0) #endif