Literal sections are not atomically live or dead. Rather,
liveness is tracked for each individual literal they contain. CStrings
have their liveness tracked via a live bit in StringPiece, and
fixed-width literals have theirs tracked via a BitVector.
The live-marking code now needs to track the offset within each section
that is to be marked live, in order to identify the literal at that
Numbers for linking chromium_framework on my 3.2 GHz 16-Core Intel Xeon W
with both -dead_strip and --deduplicate-literals, with and without this diff
N Min Max Median Avg Stddev x 20 4.32 4.44 4.375 4.372 0.03105174 + 20 4.3 4.39 4.36 4.3595 0.023277502 No difference proven at 95.0% confidence
This gives us size savings of about 0.4%.