From owner-cvs-gnu  Thu Nov  2 10:48:39 1995
Return-Path: owner-cvs-gnu
Received: (from root@localhost)
          by freefall.freebsd.org (8.6.12/8.6.6) id KAA11292
          for cvs-gnu-outgoing; Thu, 2 Nov 1995 10:48:39 -0800
Received: (from nate@localhost)
          by freefall.freebsd.org (8.6.12/8.6.6) id KAA11239
          ; Thu, 2 Nov 1995 10:48:20 -0800
Date: Thu, 2 Nov 1995 10:48:20 -0800
From: Nate Williams <nate>
Message-Id: <199511021848.KAA11239@freefall.freebsd.org>
To: CVS-commiters, cvs-gnu
Subject: cvs commit: src/gnu/usr.bin/ld/rtld rtld.c
Sender: owner-cvs-gnu@FreeBSD.org
Precedence: bulk

nate        95/11/02 10:48:17

  Modified:    gnu/usr.bin/ld/i386  md-static-funcs.c
               gnu/usr.bin/ld/rtld  rtld.c
  Log:
  Changed the terminology for what used to be called the "memorizing"
  vector.  Now it is called the "symbol caching" vector.  This was made
  possible and unconfusing by other changes that allowed me to localize
  everything having to do with the caching vector in the function
  reloc_map().
  
  Switched to alloca() for allocating the caching vector, and eliminated
  the special mmap-based allocation routines.  Although this was motivated
  by performance reasons, it led to significant simplification of the
  code, and made it possible to confine the symbol caching code to the
  single function reloc_map().
  
  Got rid of the unnecessary and inefficient division loop at the
  beginning of rtld().
  
  Reduced the number of calls to getenv("LD_LIBRARY_PATH") to just 1, on
  suggestion from <davidg@root.com>.
  
  Added breaks out of the relocation loops when the relocation address is
  found to be 0.  A relocation address of 0 is caused by an unused
  relocation entry.  Unused relocation entries are caused by linking a
  shared object with the "-Bsymbolic" switch.  The runtime linker itself
  is linked that way, and the last 40% of its relocation entries are
  unused.  Thus, breaking out of the loop on the first such entry is a
  performance win when ld.so relocates itself.  As a side benefit, it
  permits removing a test from md_relocate_simple() in
  ../i386/md-static-funcs.c.
  
  Unused relocation entries in other shared objects (linked with
  "-Bsymbolic") caused even bigger problems in previous versions of the
  runtime linker. The runtime linker interpreted the unused entries as if
  they were valid. That caused it to perform repeated relocations of the
  first byte of the shared object.  In order to do that, it had to remap
  the text segment writable.  Breaking out of the loop on the first unused
  relocation entry solves that.
  
  Submitted by:	John Polstra <jdp@polstra.com>