The Elf_Rela has an explicit addend. It doesn't need the addend to be
written to the section being relocated.
Since relative relocations are very common in the output, this is a
noticeable speedup. The results I got were
chromium
master 4.778149487
patch 4.761120792 0.996436131802
chromium fast
master 1.896253636
patch 1.840990582 0.970856718241
the gold plugin
master 0.399337811
patch 0.392279276 0.982324401032
clang
master 0.666873675
patch 0.665895708 0.998533504865
llvm-as
master 0.037101095
patch 0.037123149 1.00059442989
the gold plugin fsds
master 0.422473396
patch 0.414192879 0.980399909016
clang fsds
master 0.747302008
patch 0.744843964 0.996710775599
llvm-as fsds
master 0.033146245
patch 0.033064531 0.997534743377
scylla
master 4.08857525
patch 4.082245184 0.998451767275
llvm-svn: 269417
This is the option which sorts relocs to optimize dynamic linker performance.
-z combelocs is the default in gold, also it ignores -z nocombreloc,
this patch do the same.
Patch sorts relocations by symbols only and do not create any
DT_REL[A]COUNT entries. That is different with what gold/bfd do.
More information about option is here:
http://www.airs.com/blog/archives/186http://people.redhat.com/jakub/prelink.pdf, p.2
Differential revision: http://reviews.llvm.org/D19528
llvm-svn: 269066
MIPS N64 ABI packs multiple relocations into the single relocation
record. Particularly it requires to represent dynamic relative
relocation as a combination of R_MIPS_REL32 and R_MIPS_64 relocations.
llvm-svn: 268565