From: "Alex Bennée" <alex.bennee@linaro.org>
To: Richard Henderson <rth@twiddle.net>
Cc: qemu-devel@nongnu.org, cota@braap.org
Subject: Re: [Qemu-devel] [PATCH v5 12/19] target/i386: optimize indirect branches
Date: Fri, 28 Apr 2017 17:58:21 +0100 [thread overview]
Message-ID: <87pofw79le.fsf@linaro.org> (raw)
In-Reply-To: <20170427120006.20564-13-rth@twiddle.net>
Richard Henderson <rth@twiddle.net> writes:
> From: "Emilio G. Cota" <cota@braap.org>
>
> Speed up indirect branches by jumping to the target if it is valid.
>
> Softmmu measurements (see later commit for user-mode numbers):
>
> Note: baseline (i.e. speedup == 1x) is QEMU v2.9.0.
>
> - SPECint06 (test set), x86_64-softmmu (Ubuntu 16.04 guest). Host: Intel i7-4790K @ 4.00GHz
>
> 2.4x +-+--------------------------------------------------------------------------------------------------------------+-+
> | |
> | cross |
> 2.2x +cross+jr..........................................................................+++...........................+-+
> | | |
> | +++ | |
> 2x +-+..............................................................................|..|............................+-+
> | | | |
> | | | |
> 1.8x +-+..............................................................................|####...........................+-+
> | |# |# |
> | **** |# |
> 1.6x +-+............................................................................*.|*.|#...........................+-+
> | * |* |# |
> | * |* |# |
> 1.4x +-+.......................................................................+++..*.|*.|#...........................+-+
> | ++++++ #### * |*++# +++ |
> | +++ | | #++# *++* # +++ | |
> 1.2x +-+......................###.....####....+++............|..|...........****..#.*..*..#....####...|.###.....####..+-+
> | +++ **** # **** # #### ***### *++* # * * # #++# ****|# +++#++# |
> | ****### +++ *++* # *++* # ++# # #### *|* |# +++ * * # * * # *** # *| *|# **** # |
> 1x +-++-*++*++#++***###++*++*+#++*+-*++#+****++#++***++#+-*+*++#-+****##++*++*-+#+*++*-+#++*+*++#++*-+*+#++*++*++#-++-+
> | * * # * * # * * # * * # * * # * * # *|* |# *++* # * * # * * # * * # * * # * * # |
> | * * # * * # * * # * * # * * # * * # *+*++# * * # * * # * * # * * # * * # * * # |
> 0.8x +-+--****###--***###--****##--****###-****###--***###--***###--****##--****###-****###--***###--****##--****###--+-+
> astar bzip2 gcc gobmk h264ref hmmlibquantum mcf omnetpperlbench sjengxalancbmk hmean
> png: http://imgur.com/DU36YFU
>
> NB. 'cross' represents the previous commit.
>
> Reviewed-by: Richard Henderson <rth@twiddle.net>
> Signed-off-by: Emilio G. Cota <cota@braap.org>
> Message-Id: <1493263764-18657-11-git-send-email-cota@braap.org>
> Signed-off-by: Richard Henderson <rth@twiddle.net>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
> ---
> target/i386/translate.c | 14 ++++++++------
> 1 file changed, 8 insertions(+), 6 deletions(-)
>
> diff --git a/target/i386/translate.c b/target/i386/translate.c
> index ea113fe..674ec96 100644
> --- a/target/i386/translate.c
> +++ b/target/i386/translate.c
> @@ -4996,7 +4996,7 @@ static target_ulong disas_insn(CPUX86State *env, DisasContext *s,
> gen_push_v(s, cpu_T1);
> gen_op_jmp_v(cpu_T0);
> gen_bnd_jmp(s);
> - gen_eob(s);
> + gen_jr(s, cpu_T0);
> break;
> case 3: /* lcall Ev */
> gen_op_ld_v(s, ot, cpu_T1, cpu_A0);
> @@ -5014,7 +5014,8 @@ static target_ulong disas_insn(CPUX86State *env, DisasContext *s,
> tcg_const_i32(dflag - 1),
> tcg_const_i32(s->pc - s->cs_base));
> }
> - gen_eob(s);
> + tcg_gen_ld_tl(cpu_tmp4, cpu_env, offsetof(CPUX86State, eip));
> + gen_jr(s, cpu_tmp4);
> break;
> case 4: /* jmp Ev */
> if (dflag == MO_16) {
> @@ -5022,7 +5023,7 @@ static target_ulong disas_insn(CPUX86State *env, DisasContext *s,
> }
> gen_op_jmp_v(cpu_T0);
> gen_bnd_jmp(s);
> - gen_eob(s);
> + gen_jr(s, cpu_T0);
> break;
> case 5: /* ljmp Ev */
> gen_op_ld_v(s, ot, cpu_T1, cpu_A0);
> @@ -5037,7 +5038,8 @@ static target_ulong disas_insn(CPUX86State *env, DisasContext *s,
> gen_op_movl_seg_T0_vm(R_CS);
> gen_op_jmp_v(cpu_T1);
> }
> - gen_eob(s);
> + tcg_gen_ld_tl(cpu_tmp4, cpu_env, offsetof(CPUX86State, eip));
> + gen_jr(s, cpu_tmp4);
> break;
> case 6: /* push Ev */
> gen_push_v(s, cpu_T0);
> @@ -6417,7 +6419,7 @@ static target_ulong disas_insn(CPUX86State *env, DisasContext *s,
> /* Note that gen_pop_T0 uses a zero-extending load. */
> gen_op_jmp_v(cpu_T0);
> gen_bnd_jmp(s);
> - gen_eob(s);
> + gen_jr(s, cpu_T0);
> break;
> case 0xc3: /* ret */
> ot = gen_pop_T0(s);
> @@ -6425,7 +6427,7 @@ static target_ulong disas_insn(CPUX86State *env, DisasContext *s,
> /* Note that gen_pop_T0 uses a zero-extending load. */
> gen_op_jmp_v(cpu_T0);
> gen_bnd_jmp(s);
> - gen_eob(s);
> + gen_jr(s, cpu_T0);
> break;
> case 0xca: /* lret im */
> val = cpu_ldsw_code(env, s->pc);
--
Alex Bennée
next prev parent reply other threads:[~2017-04-28 16:57 UTC|newest]
Thread overview: 58+ messages / expand[flat|nested] mbox.gz Atom feed top
2017-04-27 11:59 [Qemu-devel] [PATCH v5 00/19] TCG cross-tb optimizations Richard Henderson
2017-04-27 11:59 ` [Qemu-devel] [PATCH v5 01/19] target/nios2: Fix 64-bit ilp32 compilation Richard Henderson
2017-04-27 16:03 ` Alex Bennée
2017-04-27 11:59 ` [Qemu-devel] [PATCH v5 02/19] tcg/sparc: Use the proper compilation flags for 32-bit Richard Henderson
2017-04-27 16:04 ` Alex Bennée
2017-04-27 11:59 ` [Qemu-devel] [PATCH v5 03/19] qemu/atomic: Loosen restrictions for 64-bit ILP32 hosts Richard Henderson
2017-04-27 16:10 ` Alex Bennée
2017-04-28 7:07 ` Richard Henderson
2017-04-28 7:47 ` Alex Bennée
2017-04-28 8:05 ` Richard Henderson
2017-04-28 10:25 ` Alex Bennée
2017-04-27 11:59 ` [Qemu-devel] [PATCH v5 04/19] exec-all: export tb_htable_lookup Richard Henderson
2017-04-27 16:10 ` Alex Bennée
2017-04-27 11:59 ` [Qemu-devel] [PATCH v5 05/19] tcg-runtime: add lookup_tb_ptr helper Richard Henderson
2017-04-28 10:29 ` Alex Bennée
2017-04-28 10:32 ` Richard Henderson
2017-04-27 11:59 ` [Qemu-devel] [PATCH v5 06/19] tcg: introduce goto_ptr opcode Richard Henderson
2017-04-28 10:32 ` Alex Bennée
2017-04-27 11:59 ` [Qemu-devel] [PATCH v5 07/19] tcg: export tcg_gen_lookup_and_goto_ptr Richard Henderson
2017-04-27 11:59 ` [Qemu-devel] [PATCH v5 08/19] target/arm: optimize cross-page direct jumps in softmmu Richard Henderson
2017-04-28 11:30 ` Alex Bennée
2017-04-27 11:59 ` [Qemu-devel] [PATCH v5 09/19] target/arm: optimize indirect branches Richard Henderson
2017-04-27 22:58 ` Emilio G. Cota
2017-04-27 11:59 ` [Qemu-devel] [PATCH v5 10/19] target/i386: introduce gen_jr helper to generate lookup_and_goto_ptr Richard Henderson
2017-04-28 16:50 ` Alex Bennée
2017-04-27 11:59 ` [Qemu-devel] [PATCH v5 11/19] target/i386: optimize cross-page direct jumps in softmmu Richard Henderson
2017-04-28 16:56 ` Alex Bennée
2017-04-29 9:14 ` Richard Henderson
2017-04-27 11:59 ` [Qemu-devel] [PATCH v5 12/19] target/i386: optimize indirect branches Richard Henderson
2017-04-28 16:58 ` Alex Bennée [this message]
2017-04-27 12:00 ` [Qemu-devel] [PATCH v5 13/19] tb-hash: improve tb_jmp_cache hash function in user mode Richard Henderson
2017-04-28 17:00 ` Alex Bennée
2017-04-28 17:44 ` Emilio G. Cota
2017-04-27 12:00 ` [Qemu-devel] [PATCH v5 14/19] target/alpha: Use tcg_gen_goto_ptr Richard Henderson
2017-04-28 17:10 ` Alex Bennée
2017-04-27 12:00 ` [Qemu-devel] [PATCH v5 15/19] tcg/i386: implement goto_ptr Richard Henderson
2017-04-27 12:00 ` [Qemu-devel] [PATCH v5 16/19] tcg/ppc: Implement goto_ptr Richard Henderson
2017-04-27 12:00 ` [Qemu-devel] [PATCH v5 17/19] tcg/aarch64: " Richard Henderson
2017-04-27 22:18 ` Emilio G. Cota
2017-04-27 12:00 ` [Qemu-devel] [PATCH v5 18/19] tcg/sparc: " Richard Henderson
2017-04-27 12:00 ` [Qemu-devel] [PATCH v5 19/19] tcg/s390: " Richard Henderson
2017-04-27 12:58 ` [Qemu-devel] [PATCH v5 00/19] TCG cross-tb optimizations no-reply
2017-04-28 19:17 ` [Qemu-devel] [PATCH v5+] " Emilio G. Cota
2017-04-28 19:17 ` [Qemu-devel] [PATCH v5 + 1/2] target/aarch64: optimize cross-page direct jumps in softmmu Emilio G. Cota
2017-04-28 19:22 ` Emilio G. Cota
2017-04-29 10:30 ` Richard Henderson
2017-05-01 2:10 ` Emilio G. Cota
2017-04-28 19:17 ` [Qemu-devel] [PATCH v5 + 2/2] target/aarch64: optimize indirect branches Emilio G. Cota
2017-04-28 21:19 ` Emilio G. Cota
2017-04-30 9:47 ` Richard Henderson
2017-04-30 10:17 ` Richard Henderson
2017-04-30 14:52 ` [Qemu-devel] [PATCH v5++] TCG cross-tb optimizations Aurelien Jarno
2017-04-30 14:52 ` [Qemu-devel] [PATCH v5++ 1/3] tcg/mips: implement goto_ptr Aurelien Jarno
2017-05-01 22:00 ` Philippe Mathieu-Daudé
2017-05-02 16:21 ` Richard Henderson
2017-05-02 19:38 ` Aurelien Jarno
2017-04-30 14:52 ` [Qemu-devel] [PATCH v5++ 2/3] target/mips: optimize cross-page direct jumps in softmmu Aurelien Jarno
2017-04-30 14:52 ` [Qemu-devel] [PATCH v5++ 3/3] target/mips: optimize indirect branches Aurelien Jarno
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