LLVM likes to emit offsets of the form foo@toc@ha+16, which we didn't
support. Generalize parseMemRef to handle this case and avoid some of
the repeated offset special-cases. Offsets are now always folded into
the SymbolRef.
This still does not quite implement a fully general GAS-compatible
parser as GAS's parser is insane. GAS in x86_64 will happily accept
things like:
1@GOTPCREL+foo
blah1@GOTPCREL-blah2+blah3-blah4+blah5 # GOTPCREL modifies blah5, rest
# of expression is an offset.
GAS actually textually pulls @GOTPCREL out of the input partway through
parsing the expression and parses the modified input! Then its normal
parser goes and maintains a running expression of a specific type and,
at each term, attempts to merge it into what it currently has. So adding
and subtracting symbols is not commutative (signs must alternate or so)
and the last symbol wins.
However its PPC64 parser is not as general and just terminates each
expression after @toc@ha and friends, except that it special-cases
foo@toc@ha+16: if it can parse one more expression after @toc@ha AND it
is a constant expression, then it is added into the running offset.
Otherwise it leaves that data unconsumed.
This is all ridiculous, so just generalize our parser slightly to cover
foo@toc@ha+16 and see how far we get from there.
Change-Id: I65970791fc10fb2638fd7be8cc841900eb997c9c
Reviewed-on: https://boringssl-review.googlesource.com/16944
Commit-Queue: Adam Langley <agl@google.com>
Reviewed-by: Adam Langley <agl@google.com>
CQ-Verified: CQ bot account: commit-bot@chromium.org <commit-bot@chromium.org>
An offset > 2^15 would exceed the range of an addi immediate on ppc64le.
Thus, rather than add the offset after loading the TOC reference, have
different tocloader functions for each (symbol, offset) pair. In this
case, the linker can handle large offsets by changing the value of
foo+offset@toc@ha accordingly.
Change-Id: Iac1481bccaf55fb0c2b080eedebaf11befdae465
Reviewed-on: https://boringssl-review.googlesource.com/16784
Commit-Queue: David Benjamin <davidben@google.com>
Reviewed-by: David Benjamin <davidben@google.com>
CQ-Verified: CQ bot account: commit-bot@chromium.org <commit-bot@chromium.org>
Most importantly, this version of delocate works for ppc64le. It should
also work for x86-64, but will need significant testing to make sure
that it covers all the cases that the previous delocate.go covered.
It's less stringtastic than the old code, however the parser isn't as
nice as I would have liked. I thought that the reason we put up with
AT&T syntax with Intel is so that assembly syntax could be somewhat
consistent across platforms. At least for ppc64le, that does not appear
to be the case.
Change-Id: Ic7e3c6acc3803d19f2c3ff5620c5e39703d74212
Reviewed-on: https://boringssl-review.googlesource.com/16464
Reviewed-by: Adam Langley <agl@google.com>
Commit-Queue: Adam Langley <agl@google.com>
CQ-Verified: CQ bot account: commit-bot@chromium.org <commit-bot@chromium.org>
