From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:46423) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1dsYJY-00084m-6B for qemu-devel@nongnu.org; Thu, 14 Sep 2017 13:52:37 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1dsYJX-0007wN-6n for qemu-devel@nongnu.org; Thu, 14 Sep 2017 13:52:36 -0400 Received: from orth.archaic.org.uk ([2001:8b0:1d0::2]:37366) by eggs.gnu.org with esmtps (TLS1.0:RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1dsYJW-0007vb-Vd for qemu-devel@nongnu.org; Thu, 14 Sep 2017 13:52:35 -0400 Received: from pm215 by orth.archaic.org.uk with local (Exim 4.89) (envelope-from ) id 1dsYJV-0005t0-U7 for qemu-devel@nongnu.org; Thu, 14 Sep 2017 18:52:33 +0100 From: Peter Maydell Date: Thu, 14 Sep 2017 18:52:49 +0100 Message-Id: <1505411573-27848-15-git-send-email-peter.maydell@linaro.org> In-Reply-To: <1505411573-27848-1-git-send-email-peter.maydell@linaro.org> References: <1505411573-27848-1-git-send-email-peter.maydell@linaro.org> Subject: [Qemu-devel] [PULL 14/18] target/arm: Avoid an extra temporary for store_exclusive List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: qemu-devel@nongnu.org From: Richard Henderson Instead of copying addr to a local temp, reuse the value (which we have just compared as equal) already saved in cpu_exclusive_addr. Signed-off-by: Richard Henderson Reviewed-by: Alistair Francis Message-id: 20170908163859.29820-1-richard.henderson@linaro.org Signed-off-by: Peter Maydell --- target/arm/translate-a64.c | 26 +++++++++----------------- 1 file changed, 9 insertions(+), 17 deletions(-) diff --git a/target/arm/translate-a64.c b/target/arm/translate-a64.c index 1bc12d9..083568c 100644 --- a/target/arm/translate-a64.c +++ b/target/arm/translate-a64.c @@ -1894,7 +1894,7 @@ static void gen_load_exclusive(DisasContext *s, int rt, int rt2, } static void gen_store_exclusive(DisasContext *s, int rd, int rt, int rt2, - TCGv_i64 inaddr, int size, int is_pair) + TCGv_i64 addr, int size, int is_pair) { /* if (env->exclusive_addr == addr && env->exclusive_val == [addr] * && (!is_pair || env->exclusive_high == [addr + datasize])) { @@ -1910,13 +1910,8 @@ static void gen_store_exclusive(DisasContext *s, int rd, int rt, int rt2, */ TCGLabel *fail_label = gen_new_label(); TCGLabel *done_label = gen_new_label(); - TCGv_i64 addr = tcg_temp_local_new_i64(); TCGv_i64 tmp; - /* Copy input into a local temp so it is not trashed when the - * basic block ends at the branch insn. - */ - tcg_gen_mov_i64(addr, inaddr); tcg_gen_brcond_i64(TCG_COND_NE, addr, cpu_exclusive_addr, fail_label); tmp = tcg_temp_new_i64(); @@ -1927,27 +1922,24 @@ static void gen_store_exclusive(DisasContext *s, int rd, int rt, int rt2, } else { tcg_gen_concat32_i64(tmp, cpu_reg(s, rt2), cpu_reg(s, rt)); } - tcg_gen_atomic_cmpxchg_i64(tmp, addr, cpu_exclusive_val, tmp, + tcg_gen_atomic_cmpxchg_i64(tmp, cpu_exclusive_addr, + cpu_exclusive_val, tmp, get_mem_index(s), MO_64 | MO_ALIGN | s->be_data); tcg_gen_setcond_i64(TCG_COND_NE, tmp, tmp, cpu_exclusive_val); } else if (s->be_data == MO_LE) { - gen_helper_paired_cmpxchg64_le(tmp, cpu_env, addr, cpu_reg(s, rt), - cpu_reg(s, rt2)); + gen_helper_paired_cmpxchg64_le(tmp, cpu_env, cpu_exclusive_addr, + cpu_reg(s, rt), cpu_reg(s, rt2)); } else { - gen_helper_paired_cmpxchg64_be(tmp, cpu_env, addr, cpu_reg(s, rt), - cpu_reg(s, rt2)); + gen_helper_paired_cmpxchg64_be(tmp, cpu_env, cpu_exclusive_addr, + cpu_reg(s, rt), cpu_reg(s, rt2)); } } else { - TCGv_i64 val = cpu_reg(s, rt); - tcg_gen_atomic_cmpxchg_i64(tmp, addr, cpu_exclusive_val, val, - get_mem_index(s), + tcg_gen_atomic_cmpxchg_i64(tmp, cpu_exclusive_addr, cpu_exclusive_val, + cpu_reg(s, rt), get_mem_index(s), size | MO_ALIGN | s->be_data); tcg_gen_setcond_i64(TCG_COND_NE, tmp, tmp, cpu_exclusive_val); } - - tcg_temp_free_i64(addr); - tcg_gen_mov_i64(cpu_reg(s, rd), tmp); tcg_temp_free_i64(tmp); tcg_gen_br(done_label); -- 2.7.4