Commit Graph

12 Commits

Author SHA1 Message Date
Simon Atanasyan afe7197f13 [mips] Use llvm-readobj `-A` flag in test cases. NFC
llvm-svn: 373589
2019-10-03 12:08:04 +00:00
Fangrui Song b159906a9a [test] Change llvm-readobj -long-option to --long-option or well-known short options. NFC
Also change some options that have different semantics (cause confusion) in llvm-readelf mode:

-s => -S
-t => --symbols
-sd => --section-data

llvm-svn: 359651
2019-05-01 05:49:01 +00:00
Fangrui Song eb75b8f8f7 [ELF] Move `# REQUIRES:` line to the top
llvm-svn: 335625
2018-06-26 16:58:19 +00:00
Simon Atanasyan 649e4d328f [MIPS] Fix PLT entries generation in case of linking regular and microMIPS code
Currently LLD calls the `isMicroMips` routine to determine type of PLT entries
needs to be generated: regular or microMIPS. This routine checks ELF
header flags in the `FirstObj` to retrieve type of linked object files.
So if the first file does not contain microMIPS code, LLD will generate
PLT entries with regular (non-microMIPS) code only.

Ideally, if a PLT entry is referenced by microMIPS code only this entry
should contain microMIPS code, if a PLT entry is referenced by regular
code this entry should contain regular code. In a "mixed" case the PLT
entry can be either microMIPS or regular, but each "cross-mode-call" has
additional cost.

It's rather difficult to implement this ideal solution. But we can
assume that if there is an input object file with microMIPS code, the
most part of the code is microMIPS too. So we need to deduce type of PLT
entries based on finally calculated ELF header flags and do not check
only the first input object file.

This change implements this.
  - The `getMipsEFlags` renamed to the `calcMipsEFlags`. The function
    called from the `LinkerDriver::link`. Result is stored in
    the Configuration::MipsEFlags field.
  - The `isMicroMips` and `isMipsR6` routines access the `MipsEFlags`
    field to get and check calculated ELF flags.
  - New types of PLT records created when necessary.

Differential revision: https://reviews.llvm.org/D37747

llvm-svn: 314675
2017-10-02 14:56:41 +00:00
Simon Atanasyan 462f84a736 [ELF][MIPS] Always collect .reginfo, .MIPS.options, and .MIPS.abiflags input sections
Do not take in account the `Live` flag while collecting .reginfo, .MIPS.options,
and .MIPS.abiflags input sections to produce corresponding output sections.
These sections have information purpose and should be always produced per
ABI requirements.

llvm-svn: 298093
2017-03-17 14:27:55 +00:00
Simon Dardis 73190d3906 [lld][mips] Correct tests for mips64 implying PIC.
Currently LLVM can only generate PIC code for MIPS64 with the N64 as
it uses the idiom "isPositionIndependent() || IsABI_N64()" throughout the
MIPS backend. r293164 changed this, causing test failures for LLD.

This patch changes the tests minimally to preserve existing test coverage
and one case where the test was "right" in the wrong circumstance.

Reviewers: atanasyan

Differential Revision: https://reviews.llvm.org/D29194

llvm-svn: 293275
2017-01-27 11:01:10 +00:00
Simon Atanasyan 85c6b44817 [ELF][MIPS] Support .MIPS.abiflags section
This section supersedes .reginfo and .MIPS.options sections. But for now
we have to support all three sections for ABI transition period.

llvm-svn: 278482
2016-08-12 06:28:49 +00:00
Simon Atanasyan 2e88174f83 [ELF][MIPS] Add more tests for ELF flags calculation. NFC
llvm-svn: 278359
2016-08-11 17:07:46 +00:00
Simon Atanasyan 5c09e067f7 [ELF][MIPS] Separate different tests by empty lines. NFC
llvm-svn: 278358
2016-08-11 17:07:43 +00:00
Simon Atanasyan 24c24fedba [ELF][MIPS] Produce a correct and complete set of MIPS ELF header flags
The patch extends the `getMipsEFlags` function. Now in that function
we iterate over all object files, parse ELF header flags and merge them.
If a file is incompatible with previously analyzed ones we show an error
or warning. That can happen if, for example, we try to link files with
incompatible ABI, ISA, NAN encoding etc.

There is an alternative solution. We can check and merge flags and
reject incompatible input modules in the `isCompatible` function which
is called from the `SymbolTable::addFile` method. But in that case we
have to save and keep somewhere a merged ELF flags combination to use it
later in the writer.

Differential Revision: http://reviews.llvm.org/D23161

llvm-svn: 277911
2016-08-06 05:11:41 +00:00
Simon Atanasyan f463709d7d [ELF][MIPS] Pick arch flag from the first input file.
LLD still does not produce a correct combination of MIPS ELF flags if
input files have different sets of ELF flags (i.e. EF_MIPS_ARCH_32 and
EF_MIPS_ARCH_32R2). But now we do not stick to "R2" ABI version and can
emit EF_MIPS_ARCH_32R6 for example.

llvm-svn: 276172
2016-07-20 20:15:24 +00:00
Simon Atanasyan 034c4cd58a [ELF] Allow target to configure ELF header flags in the output file
The patch configure ELF header flags for MIPS target. For now the flags
are hard coded. In fact they depends on ELF flags of input object files
and selected emulation.

Differential Revision: http://reviews.llvm.org/D15575

llvm-svn: 256089
2015-12-19 05:51:49 +00:00