Commit Graph

6 Commits

Author SHA1 Message Date
Rui Ueyama 8ec77e64fc ELF: Change how to handle KEEP linker script command.
You can instruct the linker to not discard sections even if they
are unused and --gc-sections option is given. The linker script
command for doing that is KEEP. The syntax is KEEP(foo) where foo
is a section name. KEEP commands are written in SECTIONS command,
so you can specify the order of sections *and* which sections
will be kept.

Each sub-command in SECTIONS command are translated into SectionRule
object. Previously, each SectionRule has `Keep` bit. However,
if you think about it, this hid information in too deep in elements
of a list. Semantically, KEEP commands aren't really related to
SECTIONS subcommands. We can keep the section list for KEEP in a
separate list. This patch does that.

llvm-svn: 267065
2016-04-21 22:00:51 +00:00
George Rimar 652852c5c0 Recommitted 266457 with fix:
* Do script driven layout only if SECTIONS section exist.

Initial commit message:

[ELF] - Implemented basic location counter support.

This patch implements location counter support. 
It also separates assign addresses for sections to assignAddressesScript() if it scipt exists.

Main testcase is test/ELF/linkerscript-locationcounter.s, It contains some work with location counter. It is basic now.
Implemented location counter assignment and '+' operations.

Patch by myself with LOTS of comments and design suggestions from Rui Ueyama.

Differential revision: http://reviews.llvm.org/D18499

llvm-svn: 266526
2016-04-16 10:10:32 +00:00
Rui Ueyama faac567e68 Revert r266457: "[ELF] - Implemented basic location counter support."
This reverts commit r266457 as it breaks "hello world" both on
Linux and FreeBSD.

llvm-svn: 266485
2016-04-15 22:39:27 +00:00
George Rimar ea25877d4a [ELF] - Implemented basic location counter support.
This patch implements location counter support. 
It also separates assign addresses for sections to assignAddressesScript() if it scipt exists.

Main testcase is test/ELF/linkerscript-locationcounter.s, It contains some work with location counter. It is basic now.
Implemented location counter assignment and '+' operations.

Patch by myself with LOTS of comments and design suggestions from Rui Ueyama.

Differential revision: http://reviews.llvm.org/D18499

llvm-svn: 266457
2016-04-15 17:44:19 +00:00
George Rimar f9c2f81812 Eliminated trailing whitespaces from test. NFC.
llvm-svn: 263933
2016-03-21 11:23:53 +00:00
George Rimar 481c2ce64b [ELF] - Linkerscript KEEP command.
When link-time garbage collection is in use (-gc-sections), it is 
often useful to mark sections that should not be eliminated. 
This is accomplished by surrounding an input section's wildcard 
entry with KEEP(). Patch implements that command.

Differential revision: http://reviews.llvm.org/D17242

llvm-svn: 261616
2016-02-23 07:47:54 +00:00