Making a (NOLOAD) section SHT_PROGBITS is fishy (the user may expect all-zero
content, but the linker does not check that), but some projects (e.g. Linux
kernel https://github.com/ClangBuiltLinux/linux/issues/1597) traditionally rely
on the behavior. Issue a warning to not break them.
The current output section type allows to set the ELF section type to
SHT_PROGBITS or SHT_NOLOAD. This patch allows an arbitrary section value
to be specified. Some common SHT_* literal names are supported as well.
```
SECTIONS {
note (TYPE=SHT_NOTE) : { BYTE(8) *(note) }
init_array ( TYPE=14 ) : { QUAD(14) }
fini_array (TYPE = SHT_FINI_ARRAY) : { QUAD(15) }
}
```
When `sh_type` is specified, it is an error if an input section has a different type.
Our syntax is compatible with GNU ld 2.39 (https://sourceware.org/bugzilla/show_bug.cgi?id=28841).
Reviewed By: peter.smith
Differential Revision: https://reviews.llvm.org/D118840
During PHDR creation, the case where an output section does not require a
PT_LOAD header but still occupies memory in the current VMA region was not handled.
If such an output section interleaves two output sections that have the same
VMA and LMA regions set, we would previously re-use the existing PT_LOAD header
for the second output section.
However, since the memory region is not contiguous, we need to start a new PT_LOAD
segment.
This fixes https://bugs.llvm.org/show_bug.cgi?id=50558
Reviewed By: MaskRay
Differential Revision: https://reviews.llvm.org/D103815
See https://lists.llvm.org/pipermail/llvm-dev/2020-July/143373.html
"[llvm-dev] Multiple documents in one test file" for some discussions.
This patch has explored several alternatives. The current semantics are similar to
what @dblaikie proposed.
`split-file filename output` splits the input file into multiple parts separated by
regex `^(.|//)--- filename` and write each part to the file `output/filename`
(`filename` can include path separators).
Use case A (organizing input of different formats (e.g. linker
script+assembly) in one file).
```
# RUN: split-file %s %t
# RUN: llvm-mc %t/asm -o %t.o
# RUN: ld.lld -T %t/lds %t.o -o %t
This is sometimes better than the %S/Inputs/ approach because the user
can see the auxiliary files immediately and don't have to open another file.
# asm
...
# lds
...
```
Use case B (for utilities which don't have built-in input splitting
feature):
```
// RUN: split-file %s %t
// RUN: llc < %t/1.ll | FileCheck %s --check-prefix=CASE1
// RUN: llc < %t/2.ll | FileCheck %s --check-prefix=CASE2
Combing tests prudently can improve readability.
For example, when testing parsing errors if the recovery mechanism isn't possible,
grouping the tests in one file can more readily see test coverage/strategy.
//--- 1.ll
...
//--- 2.ll
...
```
Since this is a new utility, there is no git history concerns for
UpperCase variable names. I use lowerCase variable names like mlir/lld.
Reviewed By: jhenderson, lattner
Differential Revision: https://reviews.llvm.org/D83834
This reverts commit d054c7ee2e9f4f98af7f22a5b00a941eb919bd59.
There are discussions about the utility name, its functionality and user interface.
Revert before we reach consensus.
See https://lists.llvm.org/pipermail/llvm-dev/2020-July/143373.html
"[llvm-dev] Multiple documents in one test file" for some discussions.
`extract part filename` splits the input file into multiple parts separated by
regex `^(.|//)--- ` and extract the specified part to stdout or the
output file (if specified).
Use case A (organizing input of different formats (e.g. linker
script+assembly) in one file).
```
// RUN: extract lds %s -o %t.lds
// RUN: extract asm %s -o %t.s
// RUN: llvm-mc %t.s -o %t.o
// RUN: ld.lld -T %t.lds %t.o -o %t
This is sometimes better than the %S/Inputs/ approach because the user
can see the auxiliary files immediately and don't have to open another file.
```
Use case B (for utilities which don't have built-in input splitting
feature):
```
// RUN: extract case1 %s | llc | FileCheck %s --check-prefix=CASE1
// RUN: extract case2 %s | llc | FileCheck %s --check-prefix=CASE2
Combing tests prudently can improve readability.
This is sometimes better than having multiple test files.
```
Since this is a new utility, there is no git history concerns for
UpperCase variable names. I use lowerCase variable names like mlir/lld.
Reviewed By: jhenderson
Differential Revision: https://reviews.llvm.org/D83834
This fixes PR# 45336.
Output sections described in a linker script as NOLOAD with no input sections would be marked as SHT_PROGBITS.
Reviewed By: MaskRay
Differential Revision: https://reviews.llvm.org/D76981
Also change some options that have different semantics (cause confusion) in llvm-readelf mode:
-s => -S
-t => --symbols
-sd => --section-data
llvm-svn: 359651
Previously, it couldn't parse
SECTIONS .text (0x1000) : { *(.text) }
because "(" was interpreted as the begining of the "(NOLOAD)" directive.
llvm-svn: 305006
