Global values imply flags such as readable, writable, executable for the
sections that they will be placed in. Currently MC places all such
entries into the same section, using the first set of flags seen. This
can lead to situations in LTO where a writable global is placed in the
same named section as a readable global from another file, and the
section may not be marked writable.
D72194 ensures that mergeable globals with explicit sections are placed
in separate sections with compatible entry size, by emitting the
`unique` assembly syntax where appropriate. This change extends that
approach to include section flags, so that globals with different
section flags are emitted in separate unique sections.
Differential revision: https://reviews.llvm.org/D100944
If a variable has an explicit section such as .sdata or .sbss, it is placed
in that section and accessed in a gp relative manner. This overrides the global
-G setting.
Otherwise if a variable has a explicit section attached to it, such as '.rodata'
or '.mysection', it is not placed in the small data section. This also overrides
the global -G setting.
Reviewers: atanasyan, nitesh.jain
Differential Revision: https://reviews.llvm.org/D36616
llvm-svn: 311001