Re: [Qemu-devel] [PATCH] Improve symbol lookup for system and user mode

["Blue Swirl" <blauwirbel@gmail.com>]

On 10/17/08, Stefan Weil <weil@mail.berlios.de> wrote:
>
>  > Stefan Weil schrieb:
>  >> Here is a short summary of my new patch:
>  >>
>  >> * Use function pointers for symbol lookup (currently for elf32 and
>  >> elf64, could be expanded).
>  >> This also fixes the bug with mips elf64 symbols in current Qemu trunk.
>  >>
>  >> * Use quicksort and binary search for symbol lookup.
>  >>
>  >> * Remove unneeded entries from symbol table.
>  >> This reduced a typical table size (linux mips kernel) from 1764487 to
>  >> 11656 entries.
>  >>
>  >> * In disas.c, the patch also fixes some warnings from old fashioned
>  >> function prototypes.

This should be a separate patch.

>  >>
>  >> In loader.c, two defines control some compile time options (could be
>  >> removed in
>  >> production code):
>  >> #define CONFIG_BINARY_SYMBOL_SEARCH
>  >> #define CONFIG_REDUCE_SYMBOL_TABLE
>  >>
>  >> I tested the new code using 32 bit and 64 bit linux mips kernels and
>  >> Qemu logging (-d in_asm).
>  >> The speed improvement is extremely large - both because of the much
>  >> smaller table and
>  >> the binary search.
>  >>
>  >> Stefan
>  >>
>  > Please note:
>  >
>  > The current patch only supports system emulation.
>  > User emulation needs more fixes to compile again.
>  >
>  > Stefan
>  >
>  >
>
>
>  Here is an updated patch which now supports binary symbol lookup
>  for both system emulation and user emulation.
>
>  User emulation was tested using qemu-x86_64 and a simple application
>  with symbol information.
>
>  The new patch no longer includes compile time options for the old
>  linear symbol search.
>
>  I hope this new patch will be included in Qemu trunk.

There are some white space only changes, these should be taken out.

For some reason, loading a bios with symbols on Sparc32 corrupts the
bios but Sparc64 works. This happens also without your patch.