JUMP_TABLES_IN_TEXT_SECTION
Jeffrey A Law
law@cygnus.com
Sat Apr 4 14:20:00 GMT 1998
In message <Pine.SOL.3.90.980220112632.20928E-100000@clouseau.informatik.rwth
-aachen.de>you write:
> The optimization manuals for Intel and AMD CPUs advise to put jump tables
> into the data section. To implement this, I've changed
> JUMP_TABLES_IN_TEXT_SECTION to have a value. For ix86-linux, the patch
> sets it to (flag_pic), which is probably appropriate for ix86-*bsd as well.
> I didn't change it, since I can't test those configurations.
> The MIPS port may also be worth looking at, it appears to kludge around the
> fact that the macro did not have a value until now.
>
> Bernd
>
> * final.c: Define JUMP_TABLES_IN_TEXT_SECTION to a default value
> of 0 if it isn't defined.
> (get_attr_length, shorten_branches, final_scan_insn): Test value
> of JUMP_TABLES_IN_TEXT_SECTION instead of just testing whether it
> is defined.
>
> * arc/arc.h: Define JUMP_TABLES_IN_TEXT_SECTION to 0.
> * m32r/m32r.h: Likewise.
> * rs6000/sysv4.h: Likewise.
> * arm/coff.h: Define JUMP_TABLES_IN_TEXT_SECTION to 1.
> * i386/386bsd.h: Likewise.
> * i386/freebsd-elf.h: Likewise.
> * i386/freebsd.h: Likewise.
> * i386/netbsd.h: Likewise.
> * i386/ptx4-i.h: Likewise.
> * i386/sysv4.h: Likewise.
> * pa/pa.h: Likewise.
> * rs6000/linux.h: Likewise.
> * rs6000/rs6000.h: Likewise.
> * sh/sh.h: Likewise.
> * sparc/sp64-elf.h: Likewise.
> * v850/v850.h: Likewise.
> * i386/linux.h: Define JUMP_TABLES_IN_TEXT_SECTION to (flag_pic).
The code in shorten_branches went through a major revision about a
week after you sent this patch. As a result the patch needs to be
revised to work with the new shorten_branches code.
If you make that update and resend the patch, I'll install it.
Thanks,
jeff
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