Summary:
Local common symbols were properly inserted into the .bss section.
However, putting external common symbols in the .bss section would give
them a strong definition.
Instead, encode them as undefined, external symbols who's symbol value
is equivalent to their size.
Reviewers: Bigcheese, rafael, rnk
CC: llvm-commits
Differential Revision: http://reviews.llvm.org/D3324
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@205811 91177308-0d34-0410-b5e6-96231b3b80d8
This is a pretty straight forward translation for COFF, we just need to
stick the data in a COMDAT section marked as
IMAGE_COMDAT_SELECT_NODUPLICATES.
N.B. We must be careful to avoid sticking entities with private linkage
in COMDAT groups. COFF is pretty hostile to the renaming of entities so
we must be careful to disallow GlobalVariables with unstable names.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@204703 91177308-0d34-0410-b5e6-96231b3b80d8
This is a pretty straight forward translation for COFF, we just need to
stick the function in a COMDAT section marked as
IMAGE_COMDAT_SELECT_NODUPLICATES.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@204565 91177308-0d34-0410-b5e6-96231b3b80d8
Summary:
llvm/MC/MCSectionMachO.h and llvm/Support/MachO.h both had the same
definitions for the section flags. Instead, grab the definitions out of
support.
No functionality change.
Reviewers: grosbach, Bigcheese, rafael
Reviewed By: rafael
CC: llvm-commits
Differential Revision: http://llvm-reviews.chandlerc.com/D2998
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@203211 91177308-0d34-0410-b5e6-96231b3b80d8
TargetLoweringBase is implemented in CodeGen, so before this patch we had
a dependency fom Target to CodeGen. This would show up as a link failure of
llvm-stress when building with -DBUILD_SHARED_LIBS=ON.
This fixes pr18900.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@201711 91177308-0d34-0410-b5e6-96231b3b80d8
r201608 made llvm corretly handle private globals with MachO. r201622 fixed
a bug in it and r201624 and r201625 were changes for using private linkage,
assuming that llvm would do the right thing.
They all got reverted because r201608 introduced a crash in LTO. This patch
includes a fix for that. The issue was that TargetLoweringObjectFile now has
to be initialized before we can mangle names of private globals. This is
trivially true during the normal codegen pipeline (the asm printer does it),
but LTO has to do it manually.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@201700 91177308-0d34-0410-b5e6-96231b3b80d8
When outputting an object we check its section to find its name, but when
looking for the section with -ffunction-section we look for the symbol name.
Break the loop by requesting a name with the private prefix when constructing
the section name. This matches the behavior before r201608.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@201622 91177308-0d34-0410-b5e6-96231b3b80d8
The IR
@foo = private constant i32 42
is valid, but before this patch we would produce an invalid MachO from it. It
was invalid because it would use an L label in a section where the liker needs
the labels in order to atomize it.
One way of fixing it would be to just reject this IR in the backend, but that
would not be very front end friendly.
What this patch does is use an 'l' prefix in sections that we know the linker
requires symbols for atomizing them. This allows frontends to just use
private and not worry about which sections they go to or how the linker handles
them.
One small issue with this strategy is that now a symbol name depends on the
section, which is not available before codegen. This is not a problem in
practice. The reason is that it only happens with private linkage, which will
be ignored by the non codegen users (llvm-nm and llvm-ar).
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@201608 91177308-0d34-0410-b5e6-96231b3b80d8
These methods normally call each other and it is really annoying if the
arguments are in different order. The more common rule was that the arguments
specific to call are first (GV, Encoding, Suffix) and the auxiliary objects
(Mang, TM) come after. This patch changes the exceptions.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@201044 91177308-0d34-0410-b5e6-96231b3b80d8
It is never null and it is not used in casts, so there is no reason to use a
pointer. This matches how we pass TM.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@201025 91177308-0d34-0410-b5e6-96231b3b80d8
code to see if we're emitting a function into a non-default
text section. This is still a less-than-ideal solution, but more
contained than r199871 to determine whether or not we're emitting
code into an array of comdat sections.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@200269 91177308-0d34-0410-b5e6-96231b3b80d8
e.g. linkonce, to TargetMachine and set it when we've done so
for ELF targets currently. This involved making TargetMachine
non-const in a TLOF use and propagating that change around - I'm
open to other ideas.
This will be used in a future commit to handle emitting debug
information with ranges.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@199871 91177308-0d34-0410-b5e6-96231b3b80d8
We currently error in clang with:
"error: thread-local storage is unsupported for the current target", but we
can start to get the llvm level ready.
When compiling
template<typename T>
struct foo {
static __declspec(thread) int bar;
};
template<typename T>
__declspec(therad) int foo<T>::bar;
template struct foo<int>;
msvc produces
SECTION HEADER #3
.tls$ name
0 physical address
0 virtual address
4 size of raw data
12F file pointer to raw data (0000012F to 00000132)
0 file pointer to relocation table
0 file pointer to line numbers
0 number of relocations
0 number of line numbers
C0301040 flags
Initialized Data
COMDAT; sym= "public: static int foo<int>::bar" (?bar@?$foo@H@@2HA)
4 byte align
Read Write
gcc produces a ".data$__emutls_v.<symbol>" for the testcase with
__declspec(thread) replaced with thread_local.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@195849 91177308-0d34-0410-b5e6-96231b3b80d8
With this patch we use simple names for COMDAT sections (like .text or .bss).
This matches the MSVC behavior.
When merging it is the COMDAT symbol that is used to decide if two sections
should be merged, so there is no point in building a fancy name.
This survived a bootstrap on mingw32.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@195798 91177308-0d34-0410-b5e6-96231b3b80d8
This is the first step to fix pr17918.
It extends the .section directive a bit, inspired by what the ELF one looks
like. The problem with using linkonce is that given
.section foo
.linkonce....
.section foo
.linkonce
we would already have switched sections when getting to .linkonce. The cleanest
solution seems to be to add the comdat information in the .section itself.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@195148 91177308-0d34-0410-b5e6-96231b3b80d8
Craig Topper
David Majnemer
Rafael Espindola
Chandler Carruth
Daniel Jasper
Eric Christopher
Yunzhong Gao
Bill Wendling