unicorn/qemu/target
Emilio G. Cota 2d16da435e
target/i386: optimize indirect branches
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.

Backports commit b4aa297781ceddef79deb0e99da7817551fa89f8 from qemu
2018-03-03 14:10:14 -05:00
..
arm target/arm: optimize indirect branches 2018-03-02 21:18:15 -05:00
i386 target/i386: optimize indirect branches 2018-03-03 14:10:14 -05:00
m68k Move target-* CPU file into a target/ folder 2018-03-01 22:50:58 -05:00
mips target/mips: fix delay slot detection in gen_msa_branch() 2018-03-02 14:15:50 -05:00
sparc cputlb and arm/sparc targets: convert mmuidx flushes from varg to bitmap 2018-03-02 10:12:40 -05:00