From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:48513) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1dIdJU-0000i3-8s for qemu-devel@nongnu.org; Wed, 07 Jun 2017 11:56:05 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1dIdJT-0005dh-2Z for qemu-devel@nongnu.org; Wed, 07 Jun 2017 11:56:04 -0400 Received: from mail-qt0-x241.google.com ([2607:f8b0:400d:c0d::241]:33167) by eggs.gnu.org with esmtps (TLS1.0:RSA_AES_128_CBC_SHA1:16) (Exim 4.71) (envelope-from ) id 1dIdJS-0005dc-Qm for qemu-devel@nongnu.org; Wed, 07 Jun 2017 11:56:02 -0400 Received: by mail-qt0-x241.google.com with SMTP id w1so1993363qtg.0 for ; Wed, 07 Jun 2017 08:56:02 -0700 (PDT) Sender: Richard Henderson From: Richard Henderson Date: Wed, 7 Jun 2017 08:55:35 -0700 Message-Id: <20170607155536.1193-7-rth@twiddle.net> In-Reply-To: <20170607155536.1193-1-rth@twiddle.net> References: <20170607155536.1193-1-rth@twiddle.net> Subject: [Qemu-devel] [PATCH v4 6/7] target/arm: Try pc-relative addresses for movi List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: qemu-devel@nongnu.org Cc: cota@braap.org Signed-off-by: Richard Henderson --- tcg/arm/tcg-target.inc.c | 44 +++++++++++++++++++++++++++++--------------- 1 file changed, 29 insertions(+), 15 deletions(-) diff --git a/tcg/arm/tcg-target.inc.c b/tcg/arm/tcg-target.inc.c index fce382f..18708b1 100644 --- a/tcg/arm/tcg-target.inc.c +++ b/tcg/arm/tcg-target.inc.c @@ -418,25 +418,39 @@ static inline void tcg_out_dat_imm(TCGContext *s, static void tcg_out_movi32(TCGContext *s, int cond, int rd, uint32_t arg) { - int rot, opc, rn; - - /* For armv7, make sure not to use movw+movt when mov/mvn would do. - Speed things up by only checking when movt would be required. - Prior to armv7, have one go at fully rotated immediates before - doing the decomposition thing below. */ - if (!use_armv7_instructions || (arg & 0xffff0000)) { - rot = encode_imm(arg); + int rot, opc, rn, diff; + + /* Check a single MOV/MVN before anything else. */ + rot = encode_imm(arg); + if (rot >= 0) { + tcg_out_dat_imm(s, cond, ARITH_MOV, rd, 0, + rotl(arg, rot) | (rot << 7)); + return; + } + rot = encode_imm(~arg); + if (rot >= 0) { + tcg_out_dat_imm(s, cond, ARITH_MVN, rd, 0, + rotl(~arg, rot) | (rot << 7)); + return; + } + + /* Check for a pc-relative address. This will usually be the TB, + or within the TB, which is immediately before the code block. */ + diff = arg - ((intptr_t)s->code_ptr + 8); + if (diff >= 0) { + rot = encode_imm(diff); if (rot >= 0) { - tcg_out_dat_imm(s, cond, ARITH_MOV, rd, 0, - rotl(arg, rot) | (rot << 7)); + tcg_out_dat_imm(s, cond, ARITH_ADD, rd, TCG_REG_PC, + rotl(diff, rot) | (rot << 7)); return; - } - rot = encode_imm(~arg); + } + } else { + rot = encode_imm(-diff); if (rot >= 0) { - tcg_out_dat_imm(s, cond, ARITH_MVN, rd, 0, - rotl(~arg, rot) | (rot << 7)); + tcg_out_dat_imm(s, cond, ARITH_SUB, rd, TCG_REG_PC, + rotl(-diff, rot) | (rot << 7)); return; - } + } } /* Use movw + movt. */ -- 2.9.4