Add file-level comments
Replace trivial Input/*.s with echo ... | llvm-mc
Delete insignificant addresses to make them more tolerant to layout changes
Simplify test output
Merge merge-section-types.s into compatible-section-types.s and add a missed case
Merge gnu-ifunc-gotpcrel.s (added in D19517) into gnu-ifunc-dso.s (added in D35119) and add missed cases
Delete typed-undef.s - covered by executable-undefined-ignoreall.s
Delete emit-relocs-shared.s - covered by emit-relocs-merge.s
Replace copy-rel-pie.s and copy-rel-pie2.s with canonical-plt-pcrel.s, canonical-plt-symbolic.s and copy-rel.s:
add -no-pie cases.
add a case that a canonical PLT can be created for STT_GNU_IFUNC. The logic in Symbols.h was untested:
// ctor of SharedSymbol
if (this->type == llvm::ELF::STT_GNU_IFUNC)
this->type = llvm::ELF::STT_FUNC;
llvm-svn: 371361
Old: PT_LOAD(.data | PT_GNU_RELRO(.data.rel.ro .bss.rel.ro) | .bss)
New: PT_LOAD(PT_GNU_RELRO(.data.rel.ro .bss.rel.ro) | .data .bss)
The placement of | indicates page alignment caused by PT_GNU_RELRO. The
new layout has simpler rules and saves space for many cases.
Old size: roundup(.data) + roundup(.data.rel.ro)
New size: roundup(.data.rel.ro + .bss.rel.ro) + .data
Other advantages:
* At runtime the 3 memory mappings decrease to 2.
* start(PT_TLS) = start(PT_GNU_RELRO) = start(RW PT_LOAD). This
simplifies binary manipulation tools.
GNU strip before 2.31 discards PT_GNU_RELRO if its
address is not equal to the start of its associated PT_LOAD.
This has been fixed by https://sourceware.org/git/gitweb.cgi?p=binutils-gdb.git;h=f2731e0c374e5323ce4cdae2bcc7b7fe22da1a6f
But with this change, we will be compatible with GNU strip before 2.31
* Before, .got.plt (non-relro by default) was placed before .got (relro
by default), which made it impossible to have _GLOBAL_OFFSET_TABLE_
(start of .got.plt on x86-64) equal to the end of .got (R_GOT*_FROM_END)
(https://bugs.llvm.org/show_bug.cgi?id=36555). With the new ordering, we
can improve on this regard if we'd like to.
Reviewers: ruiu, espindola, pcc
Subscribers: emaste, arichardson, llvm-commits, joerg, jdoerfert
Differential Revision: https://reviews.llvm.org/D56828
llvm-svn: 356117
With fix for undefined weak symbols in executable.
Original commit message:
This is PR32112. Previously when we linked executable with
--unresolved-symbols=ignore-all and undefined symbols, like:
_start:
callq und@PLT
we did not create relocations, though it looks in that case
we should delegate handling of such symbols to runtime linker,
hence should emit them. Patch fixes that.
Differential revision: https://reviews.llvm.org/D35724
llvm-svn: 309796
This is PR32112. Previously when we linked executable with
--unresolved-symbols=ignore-all and undefined symbols, like:
_start:
callq und@PLT
we did not create relocations, though it looks in that case
we should delegate handling of such symbols to runtime linker,
hence should emit them. Patch fixes that.
Differential revision: https://reviews.llvm.org/D35724
llvm-svn: 309252