Commit Graph

8 Commits

Author SHA1 Message Date
Fangrui Song e36223c85c [ELF] Enforce two dashes for Flag options not supported by GNU ld (i.e. no compatibility burden)
Announced on https://lists.llvm.org/pipermail/llvm-dev/2020-May/141416.html

Similar to D79371, but for `multiclass B` (convenience helper for defining --foo and --no-foo)

Some changed options are also used by gold, but I haven't seen their
one-dash use cases outside of lld's testsuite.
2020-05-15 11:07:25 -07:00
Fangrui Song e96d7b5e9e [ELF] Add --rosegment to complement --no-rosegment
This option can cancel --no-rosegment and it just seems right to have
a corresponding positive option for a --no-* negative option.

Anecdotally, gold had --rosegment but did not have --no-rosegment.
I added --no-rosegment (https://sourceware.org/git/?p=binutils-gdb.git;a=commit;h=9a6c68caa9543e09b064b7ac7c2b658f277bc19c) for binutils>=2.35
2020-04-29 18:00:00 -07:00
Fangrui Song d4306e90cb [ELF][X86] Allow PT_LOAD to have overlapping p_offset ranges on EM_X86_64
Port the D64906 technique to EM_X86_64.

Differential Revision: https://reviews.llvm.org/D67482

llvm-svn: 371958
2019-09-16 07:05:34 +00:00
Fangrui Song e8c0d93360 [ELF] nmagic or omagic: don't allocate PT_PHDR or PF_R PT_LOAD for the !hasPhdrsCommands case
```
part.phdrs = script->hasPhdrsCommands() ? script->createPhdrs() : createPhdrs(part);
```

createPhdrs() allocates a PT_PHDR and a PF_R PT_LOAD, which will be
deleted later in LinkerScript::allocateHeaders, but leave a gap between
the program headers and the first section. Don't allocate the segments
to avoid the gap. PT_INTERP is likely not needed as well.

Reviewed By: ruiu

Differential Revision: https://reviews.llvm.org/D67324

llvm-svn: 371398
2019-09-09 13:08:51 +00:00
Peter Smith 4e21c770ec [ELF] Full support for -n (--nmagic) and -N (--omagic) via common page
The -n (--nmagic) disables page alignment, and acts as a -Bstatic
The -N (--omagic) does what -n does but also marks the executable segment as
writeable. As page alignment is disabled headers are not allocated unless
explicit in the linker script.

To disable page alignment in LLD we choose to set the page sizes to 1 so
that any alignment based on the page size does nothing. To set the
Target->PageSize to 1 we implement -z common-page-size, which has the side
effect of allowing the user to set the value as well.

Setting the page alignments to 1 does mean that any use of
CONSTANT(MAXPAGESIZE) or CONSTANT(COMMONPAGESIZE) in a linker script will
return 1, unlike in ld.bfd. However given that -n and -N disable paging
these probably shouldn't be used in a linker script where -n or -N is in
use.

Differential Revision: https://reviews.llvm.org/D61688

llvm-svn: 360593
2019-05-13 16:01:26 +00:00
Rui Ueyama 700b1f8a56 Add --no-omagic and --no-print-gc-sections.
llvm-svn: 317068
2017-11-01 02:04:43 +00:00
George Rimar 595a763f38 [ELF] - Implemented -N (-omagic) command line option.
-N (-omagic)
  Set the text and data sections to be readable and writable. 
  Also, do not page-align the data segment.

Differential revision: https://reviews.llvm.org/D26888

llvm-svn: 288123
2016-11-29 09:43:51 +00:00
George Rimar 63bf011003 [ELF] - Implemented -no-rosegment.
--no-rosegment: Do not put read-only non-executable sections in their own segment

Differential revision: https://reviews.llvm.org/D26889

llvm-svn: 288020
2016-11-28 10:05:20 +00:00