Add support for having multiple sections with the same name and comdat.
Using this in combination with -ffunction-sections allows LLVM to output a .o
file with mulitple sections named .text. This saves space by avoiding long
unique names of the form .text.<C++ mangled name>.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@229541 91177308-0d34-0410-b5e6-96231b3b80d8
Original message:
Invert the section relocation map.
It now points from rel section to section. Use it to set sh_info, avoiding
a brittle name lookup.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@229539 91177308-0d34-0410-b5e6-96231b3b80d8
Original message:
Create the Seciton -> Rel Section map when it is first needed. NFC.
Saves a walk over every section.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@229536 91177308-0d34-0410-b5e6-96231b3b80d8
Introduces a subset of C++14 integer sequences in STLExtras. This is
just enough to support unpacking a std::tuple into the arguments of
snprintf, we can add more of it when it's actually needed.
Also removes an ancient macro hack that leaks a macro into the global
namespace. Clean up users that made use of the convenient hack.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@229337 91177308-0d34-0410-b5e6-96231b3b80d8
regressions for LLDB on Linux. Rafael indicated on lldb-dev that we
should just go ahead and revert these but that he wasn't at a computer.
The patches backed out are as follows:
r228980: Add support for having multiple sections with the name and ...
r228889: Invert the section relocation map.
r228888: Use the existing SymbolTableIndex intsead of doing a lookup.
r228886: Create the Section -> Rel Section map when it is first needed.
These patches look pretty nice to me, so hoping its not too hard to get
them re-instated. =D
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@229080 91177308-0d34-0410-b5e6-96231b3b80d8
Using this in combination with -ffunction-sections allows LLVM to output a .o
file with mulitple sections named .text. This saves space by avoiding long
unique names of the form .text.<C++ mangled name>.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@228980 91177308-0d34-0410-b5e6-96231b3b80d8
COFF section flags are not idempotent:
'rd' will make a read-write section because 'd' implies write
'dr' will make a read-only section because 'r' disables write
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@228490 91177308-0d34-0410-b5e6-96231b3b80d8
Any code creating an MCSectionELF knows ELF and already provides the flags.
SectionKind is an abstraction used by common code that uses a plain
MCSection.
Use the flags to compute the SectionKind. This removes a lot of
guessing and boilerplate from the MCSectionELF construction.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@227476 91177308-0d34-0410-b5e6-96231b3b80d8
The ELF format is used on Windows by the MCJIT engine. Thus, on Windows, the
ELFObjectWriter can encounter symbols mangled using the MS Visual Studio C++
name mangling. Symbols mangled using the MSVC C++ name mangling can legally
have "@@@" as a substring. The EFLObjectWriter should not interpret the "@@@"
substring as specifying GNU-style symbol versioning. The ELFObjectWriter
therefore check for the MSVC C++ name mangling prefix which is either "?", "@?",
"imp_?" or "imp_?@".
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@226830 91177308-0d34-0410-b5e6-96231b3b80d8
Windows supports a restricted set of relocations (compared to ARM ELF). In some
cases, we may end up generating an unsupported relocation. This can occur with
bad input to the assembler in particular (the frontend should never generate
code that cannot be compiled). Generate an error rather than just aborting.
The change in the API is driven by the desire to provide a slightly more helpful
message for debugging purposes.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@226779 91177308-0d34-0410-b5e6-96231b3b80d8
The fixes are to note that AArch64 has additional restrictions on when local
relocations can be used. In particular, ld64 requires that relocations to
cstring/cfstrings use linker visible symbols.
Original message:
In an assembly expression like
bar:
.long L0 + 1
the intended semantics is that bar will contain a pointer one byte past L0.
In sections that are merged by content (strings, 4 byte constants, etc), a
single position in the section doesn't give the linker enough information.
For example, it would not be able to tell a relocation must point to the
end of a string, since that would look just like the start of the next.
The solution used in ELF to use relocation with symbols if there is a non-zero
addend.
In MachO before this patch we would just keep all symbols in some sections.
This would miss some cases (only cstrings on x86_64 were implemented) and was
inefficient since most relocations have an addend of 0 and can be represented
without the symbol.
This patch implements the non-zero addend logic for MachO too.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@226503 91177308-0d34-0410-b5e6-96231b3b80d8
An assignment will produce a symbol with a given section and offset. There is
no way to represent something like "1 byte after a common symbol".
This matches the behavior of GNU as.
Part of PR22217.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@226470 91177308-0d34-0410-b5e6-96231b3b80d8
This patch was generated by a clang tidy checker that is being open sourced.
The documentation of that checker is the following:
/// The emptiness of a container should be checked using the empty method
/// instead of the size method. It is not guaranteed that size is a
/// constant-time function, and it is generally more efficient and also shows
/// clearer intent to use empty. Furthermore some containers may implement the
/// empty method but not implement the size method. Using empty whenever
/// possible makes it easier to switch to another container in the future.
Patch by Gábor Horváth!
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@226161 91177308-0d34-0410-b5e6-96231b3b80d8
utils/sort_includes.py.
I clearly haven't done this in a while, so more changed than usual. This
even uncovered a missing include from the InstrProf library that I've
added. No functionality changed here, just mechanical cleanup of the
include order.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@225974 91177308-0d34-0410-b5e6-96231b3b80d8
These intrinsics allow multiple functions to share a single stack
allocation from one function's call frame. The function with the
allocation may only perform one allocation, and it must be in the entry
block.
Functions accessing the allocation call llvm.recoverframeallocation with
the function whose frame they are accessing and a frame pointer from an
active call frame of that function.
These intrinsics are very difficult to inline correctly, so the
intention is that they be introduced rarely, or at least very late
during EH preparation.
Reviewers: echristo, andrew.w.kaylor
Differential Revision: http://reviews.llvm.org/D6493
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@225746 91177308-0d34-0410-b5e6-96231b3b80d8
One is that AArch64 has additional restrictions on when local relocations can
be used. We have to take those into consideration when deciding to put a L
symbol in the symbol table or not.
The other is that ld64 requires the relocations to cstring to use linker
visible symbols on AArch64.
Thanks to Michael Zolotukhin for testing this!
Remove doesSectionRequireSymbols.
In an assembly expression like
bar:
.long L0 + 1
the intended semantics is that bar will contain a pointer one byte past L0.
In sections that are merged by content (strings, 4 byte constants, etc), a
single position in the section doesn't give the linker enough information.
For example, it would not be able to tell a relocation must point to the
end of a string, since that would look just like the start of the next.
The solution used in ELF to use relocation with symbols if there is a non-zero
addend.
In MachO before this patch we would just keep all symbols in some sections.
This would miss some cases (only cstrings on x86_64 were implemented) and was
inefficient since most relocations have an addend of 0 and can be represented
without the symbol.
This patch implements the non-zero addend logic for MachO too.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@225644 91177308-0d34-0410-b5e6-96231b3b80d8
This adds support for parsing and emitting the SBREL relocation variant for the
ARM target. Handling this relocation variant is necessary for supporting the
full ARM ELF specification. Addresses PR22128.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@225595 91177308-0d34-0410-b5e6-96231b3b80d8
This is affecting the behavior of some ObjC++ / AArch64 test cases on Darwin.
Reverting to get the bots green while I track down the source of the changed
behavior.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@225311 91177308-0d34-0410-b5e6-96231b3b80d8
The issues was that AArch64 has additional restrictions on when local
relocations can be used. We have to take those into consideration when
deciding to put a L symbol in the symbol table or not.
Original message:
Remove doesSectionRequireSymbols.
In an assembly expression like
bar:
.long L0 + 1
the intended semantics is that bar will contain a pointer one byte past L0.
In sections that are merged by content (strings, 4 byte constants, etc), a
single position in the section doesn't give the linker enough information.
For example, it would not be able to tell a relocation must point to the
end of a string, since that would look just like the start of the next.
The solution used in ELF to use relocation with symbols if there is a non-zero
addend.
In MachO before this patch we would just keep all symbols in some sections.
This would miss some cases (only cstrings on x86_64 were implemented) and was
inefficient since most relocations have an addend of 0 and can be represented
without the symbol.
This patch implements the non-zero addend logic for MachO too.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@225048 91177308-0d34-0410-b5e6-96231b3b80d8
GCC does this for non-zero discriminators and since GCC doesn't produce
column info, that was the only place it comes up there. For LLVM, since
we can emit discriminators and/or column info, it makes more sense to
invert the condition and just test for changes in line number.
This should resolve at least some of the GDB 7.5 test suite failures
created by recent Clang changes that increase the location fidelity
(which, since Clang defaults to including column info on Linux by
default created a bunch of cases that confused GDB).
In theory we could do this better/differently by grouping actual source
statements together in a similar manner to the way lexical scopes are
handled but given that GDB isn't really in a position to consume that (&
users are probably somewhat used to different lines being different
'statements') this seems the safest and cheapest change. (I'm concerned
that doing this 'right' would bloat the debugloc data even further -
something Duncan's working hard to address)
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@225011 91177308-0d34-0410-b5e6-96231b3b80d8
In an assembly expression like
bar:
.long L0 + 1
the intended semantics is that bar will contain a pointer one byte past L0.
In sections that are merged by content (strings, 4 byte constants, etc), a
single position in the section doesn't give the linker enough information.
For example, it would not be able to tell a relocation must point to the
end of a string, since that would look just like the start of the next.
The solution used in ELF to use relocation with symbols if there is a non-zero
addend.
In MachO before this patch we would just keep all symbols in some sections.
This would miss some cases (only cstrings on x86_64 were implemented) and was
inefficient since most relocations have an addend of 0 and can be represented
without the symbol.
This patch implements the non-zero addend logic for MachO too.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@224985 91177308-0d34-0410-b5e6-96231b3b80d8
.set directives may be overridden by other .set directives as well as
label definitions.
This fixes PR22019.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@224811 91177308-0d34-0410-b5e6-96231b3b80d8
Correct the line information generation for preprocessed assembly. Although we
tracked the source information for the macro instantiation, we failed to account
for the fact that we were instantiating a macro, which is populated into a new
buffer and that the line information would be relative to the definition rather
than the actual instantiation location. This could cause the line number
associated with the statement to be very high due to wrapping of the difference
calculated for the preprocessor line information emitted into the stream.
Properly calculate the line for the macro instantiation, referencing the line
where the macro is actually used as GCC/gas do.
The test case uses x86, though the same problem exists on any other target using
the LLVM IAS.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@224810 91177308-0d34-0410-b5e6-96231b3b80d8
