From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from wout3-smtp.messagingengine.com (wout3-smtp.messagingengine.com [64.147.123.19]) by sourceware.org (Postfix) with ESMTPS id D8192383FBBB for ; Mon, 31 Oct 2022 15:47:11 +0000 (GMT) DMARC-Filter: OpenDMARC Filter v1.4.1 sourceware.org D8192383FBBB Authentication-Results: sourceware.org; dmarc=none (p=none dis=none) header.from=danielengel.com Authentication-Results: sourceware.org; spf=pass smtp.mailfrom=danielengel.com Received: from compute5.internal (compute5.nyi.internal [10.202.2.45]) by mailout.west.internal (Postfix) with ESMTP id BF8133200974; Mon, 31 Oct 2022 11:47:10 -0400 (EDT) Received: from mailfrontend1 ([10.202.2.162]) by compute5.internal (MEProxy); Mon, 31 Oct 2022 11:47:11 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=danielengel.com; h=cc:cc:content-transfer-encoding:date:date:from:from :in-reply-to:in-reply-to:message-id:mime-version:references :reply-to:sender:subject:subject:to:to; s=fm1; t=1667231230; x= 1667317630; bh=IheOd4UT7YUTSAMbCVlAbTMEZnE7dlXUisX6zATjPk4=; b=b CVvrfvGY8ZdpiOoX26N8NrciqsaFGZdsL6mFVOzwPTvvt4UhbuIVcL0WZvUgDTPv Fyh79RTDZQ3aX9L1TOpzMKsj+XrZV2owupV+o2CChIRtIBrjnGJKp27atTe+I7kF nLOHnH4karudpitDZwoTMiVFSFnl/wws7EGOIV8yrdWSn9lXcKFiZ8g+DSRKXcxc P/wg3sSQu+uociSeLDaHgO9+Dla5tY1AfmOBbUscLs/pvUxHrb1zdY+XpEM2MG97 ndjyjQ1rowh3V/y1WYe28dirOcKUcRQczPa6ekDVaIKPxD7En8hSuKhzH5yLAPEQ Hxrj6DJhukRO0EV0m3hng== DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d= messagingengine.com; h=cc:cc:content-transfer-encoding:date:date :feedback-id:feedback-id:from:from:in-reply-to:in-reply-to :message-id:mime-version:references:reply-to:sender:subject :subject:to:to:x-me-proxy:x-me-proxy:x-me-sender:x-me-sender :x-sasl-enc; s=fm3; t=1667231230; x=1667317630; bh=IheOd4UT7YUTS AMbCVlAbTMEZnE7dlXUisX6zATjPk4=; b=EhuModMvudoTfm/6RVlsO1lvdcPiP r2kvPSgOmCMavOcf2kHE6sElVD7qJiUgT/J9iZqbfR+7yiW+8w2HerrOZ9RSV8K2 ozE0BtZbqkNfCldHdLOQ4YrMmABZFfa4H5PP8I/H4ZoI9jjXeBXGpIUTG1WRVSqR RKiE7Is2p+1t2eYn+0IL/zvEAWYD9tdOB8szFdSFXP6j82028d3r2OL/Feaizc1Q x11zvKxqm6TvNj1wWZ5MuMtu4qusoRc8cq95OJnL1BGWjFYt+KV2hvu1p08EQUGl A0LtwxXXbXH9KbMjdimg8UpINF4pU27PnXvdRb3cIf4KRYvVKBivazO8A== X-ME-Sender: X-ME-Received: X-ME-Proxy-Cause: gggruggvucftvghtrhhoucdtuddrgedvgedrudefgdejlecutefuodetggdotefrodftvf curfhrohhfihhlvgemucfhrghsthforghilhdpqfgfvfdpuffrtefokffrpgfnqfghnecu uegrihhlohhuthemuceftddtnecusecvtfgvtghiphhivghnthhsucdlqddutddtmdenuc fjughrpefhvfevufffkffojghfggfgsedtkeertdertddtnecuhfhrohhmpeffrghnihgv lhcugfhnghgvlhcuoehgnhhusegurghnihgvlhgvnhhgvghlrdgtohhmqeenucggtffrrg htthgvrhhnpeetfeefvdelfffhteeiteehfeekuedtteekheevjedtjefhudehheejjedv udffveenucffohhmrghinheptghliidvrdhssgdpghhnuhdrohhrghenucevlhhushhtvg hrufhiiigvpedtnecurfgrrhgrmhepmhgrihhlfhhrohhmpehgnhhusegurghnihgvlhgv nhhgvghlrdgtohhm X-ME-Proxy: Feedback-ID: i791144d6:Fastmail Received: by mail.messagingengine.com (Postfix) with ESMTPA; Mon, 31 Oct 2022 11:47:09 -0400 (EDT) Received: from ubuntu.lorien.danielengel.com (ubuntu.lorien.danielengel.com [10.0.0.96]) by sendmail.lorien.danielengel.com (8.15.2/8.15.2) with ESMTP id 29VFl1L3087265; Mon, 31 Oct 2022 08:47:01 -0700 (PDT) (envelope-from gnu@danielengel.com) From: Daniel Engel To: Richard Earnshaw , gcc-patches@gcc.gnu.org Cc: Daniel Engel , Christophe Lyon Subject: [PATCH v7 12/34] Import 'clrsb' functions from the CM0 library Date: Mon, 31 Oct 2022 08:45:07 -0700 Message-Id: <20221031154529.3627576-13-gnu@danielengel.com> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20221031154529.3627576-1-gnu@danielengel.com> References: <20221031154529.3627576-1-gnu@danielengel.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Spam-Status: No, score=-13.3 required=5.0 tests=BAYES_00,DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,DKIM_VALID_EF,GIT_PATCH_0,JMQ_SPF_NEUTRAL,KAM_SHORT,RCVD_IN_DNSWL_LOW,SPF_HELO_PASS,SPF_PASS,TXREP autolearn=ham autolearn_force=no version=3.4.6 X-Spam-Checker-Version: SpamAssassin 3.4.6 (2021-04-09) on server2.sourceware.org List-Id: This implementation provides an efficient tail call to __clzsi2(), making the functions rather smaller and faster than the C versions. gcc/libgcc/ChangeLog: 2022-10-09 Daniel Engel * config/arm/bits/clz2.S (__clrsbsi2, __clrsbdi2): Added new functions. * config/arm/t-elf (LIB1ASMFUNCS): Added new function objects _clrsbsi2 and _clrsbdi2). --- libgcc/config/arm/clz2.S | 108 ++++++++++++++++++++++++++++++++++++++- libgcc/config/arm/t-elf | 2 + 2 files changed, 108 insertions(+), 2 deletions(-) diff --git a/libgcc/config/arm/clz2.S b/libgcc/config/arm/clz2.S index ed04698fef4..3d40811278b 100644 --- a/libgcc/config/arm/clz2.S +++ b/libgcc/config/arm/clz2.S @@ -1,4 +1,4 @@ -/* clz2.S: Cortex M0 optimized 'clz' functions +/* clz2.S: ARM optimized 'clz' and related functions Copyright (C) 2018-2022 Free Software Foundation, Inc. Contributed by Daniel Engel (gnu@danielengel.com) @@ -23,7 +23,7 @@ . */ -#if defined(__ARM_FEATURE_CLZ) && __ARM_FEATURE_CLZ +#ifdef __ARM_FEATURE_CLZ #ifdef L_clzdi2 @@ -242,3 +242,107 @@ FUNC_END clzdi2 #endif /* !__ARM_FEATURE_CLZ */ + +#ifdef L_clrsbdi2 + +// int __clrsbdi2(int) +// Counts the number of "redundant sign bits" in $r1:$r0. +// Returns the result in $r0. +// Uses $r2 and $r3 as scratch space. +FUNC_START_SECTION clrsbdi2 .text.sorted.libgcc.clz2.clrsbdi2 + CFI_START_FUNCTION + + #if defined(__ARM_FEATURE_CLZ) && __ARM_FEATURE_CLZ + // Invert negative signs to keep counting zeros. + asrs r3, xxh, #31 + eors xxl, r3 + eors xxh, r3 + + // Same as __clzdi2(), except that the 'C' flag is pre-calculated. + // Also, the trailing 'subs', since the last bit is not redundant. + do_it eq, et + clzeq r0, xxl + clzne r0, xxh + addeq r0, #32 + subs r0, #1 + RET + + #else /* !__ARM_FEATURE_CLZ */ + // Result if all the bits in the argument are zero. + // Set it here to keep the flags clean after 'eors' below. + movs r2, #31 + + // Invert negative signs to keep counting zeros. + asrs r3, xxh, #31 + eors xxh, r3 + + #if defined(__ARMEB__) && __ARMEB__ + // If the upper word is non-zero, return '__clzsi2(upper) - 1'. + bne SYM(__internal_clzsi2) + + // The upper word is zero, prepare the lower word. + movs r0, r1 + eors r0, r3 + + #else /* !__ARMEB__ */ + // Save the lower word temporarily. + // This somewhat awkward construction adds one cycle when the + // branch is not taken, but prevents a double-branch. + eors r3, r0 + + // If the upper word is non-zero, return '__clzsi2(upper) - 1'. + movs r0, r1 + bne SYM(__internal_clzsi2) + + // Restore the lower word. + movs r0, r3 + + #endif /* !__ARMEB__ */ + + // The upper word is zero, return '31 + __clzsi2(lower)'. + adds r2, #32 + b SYM(__internal_clzsi2) + + #endif /* !__ARM_FEATURE_CLZ */ + + CFI_END_FUNCTION +FUNC_END clrsbdi2 + +#endif /* L_clrsbdi2 */ + + +#ifdef L_clrsbsi2 + +// int __clrsbsi2(int) +// Counts the number of "redundant sign bits" in $r0. +// Returns the result in $r0. +// Uses $r2 and possibly $r3 as scratch space. +FUNC_START_SECTION clrsbsi2 .text.sorted.libgcc.clz2.clrsbsi2 + CFI_START_FUNCTION + + // Invert negative signs to keep counting zeros. + asrs r2, r0, #31 + eors r0, r2 + + #if defined(__ARM_FEATURE_CLZ) && __ARM_FEATURE_CLZ + // Count. + clz r0, r0 + + // The result for a positive value will always be >= 1. + // By definition, the last bit is not redundant. + subs r0, #1 + RET + + #else /* !__ARM_FEATURE_CLZ */ + // Result if all the bits in the argument are zero. + // By definition, the last bit is not redundant. + movs r2, #31 + b SYM(__internal_clzsi2) + + #endif /* !__ARM_FEATURE_CLZ */ + + CFI_END_FUNCTION +FUNC_END clrsbsi2 + +#endif /* L_clrsbsi2 */ + diff --git a/libgcc/config/arm/t-elf b/libgcc/config/arm/t-elf index 33b83ac4adf..89071cebe45 100644 --- a/libgcc/config/arm/t-elf +++ b/libgcc/config/arm/t-elf @@ -31,6 +31,8 @@ LIB1ASMFUNCS += \ _ashldi3 \ _ashrdi3 \ _lshrdi3 \ + _clrsbsi2 \ + _clrsbdi2 \ _clzdi2 \ _ctzdi2 \ _dvmd_tls \ -- 2.34.1