We can now use this to decide whether to emit a verneed during the final
pass over the symbols. We were previously wrongly creating a verneed entry
in the case where all references to a DSO's symbols were weak.
In a future change we may also want to use the used bit to control whether
shared symbols are preemptible and appear in the dynsym. This seems a little
tricky to do at the moment because isNeeded() is templated.
The only other functional change here is that we emit a DT_NEEDED for DSOs
whose symbols are all preempted by objects that appear later in the link. But
that doesn't seem too important to me.
Differential Revision: http://reviews.llvm.org/D21171
llvm-svn: 272282
This reverts r272275. This actually wasn't the right way to fix the problem. The correct solution is in r272279.
Applying the fix to LLVM as done in r272279, means this fix will get picked up by all projects building out of tree using LLVM's CMake modules. As opposed to the fix I had in r272275, which would require each project to change.
llvm-svn: 272280
This is the more-correct fix to out-of-tree building. AddLLVM.cmake relies on this variable being set, so we should make sure it is set in LLVMConfig.cmake.
llvm-svn: 272279
In order to make this happen, I have added permissions to sections so that we can know what the permissions are for a given section, and modified both core file plug-ins to override Process::GetMemoryRegionInfo() and answer things correctly.
llvm-svn: 272276
The out-of-tree build needs to read LLVM_TOOLS_INSTALL_DIR out of TOOLS_BINARY_DIR because LLVM_TOOLS_INSTALL_DIR is used by AddLLVM.cmake
llvm-svn: 272275
MSVC doesn't allow std::atomic<>s in a union since they don't have trivial
copy constructor. Replacing them with e.g. std::atomic_int works, but that
breaks the GCC build on Linux, because then calls to e.g. std::atomic_load_explicit
fail, as they expect a real std::atomic<> pointer.
Fixing this with an #ifdef to unbreak the build for now.
llvm-svn: 272271
This reapplies commit r271930, r271915, r271923. They hit a bug in
Thumb which is fixed in r272258 now.
The original message:
The code layout that TailMerging (inside BranchFolding) works on is not the
final layout optimized based on the branch probability. Generally, after
BlockPlacement, many new merging opportunities emerge.
This patch calls Tail Merging after MBP and calls MBP again if Tail Merging
merges anything.
llvm-svn: 272267
This enables use of the 'S' constraint for inline ASM operands on
SystemZ, which allows for a memory reference with a signed 20-bit
immediate displacement. This patch includes corresponding documentation
and test case updates.
I've changed the 'T' constraint to match the new behavior for 'S', as
'T' also uses a long displacement (though index constraints are still
not implemented). I also changed 'm' to match the behavior for 'S' as
this will allow for a wider range of displacements for 'm', though
correct me if that's not the right decision.
Author: colpell
Differential Revision: http://reviews.llvm.org/D21097
llvm-svn: 272266
Summary:
we want to exclude friend declaration, but the `DeclContext` of a
friend function declaration is not the class in which it is declared, so we need
to explicitly check if the parent is a `friendDecl`.
Reviewers: bkramer
Subscribers: cfe-commits
Differential Revision: http://reviews.llvm.org/D21175
llvm-svn: 272261
ReplaceTailWithBranchTo assumed that if an instruction is predicated, it must be part of an IT block. This is not correct for conditional branches.
No testcase as this was triggered by the reverted patch r272017 - test coverage will occur when that patch is re-reverted and there is no known way to trigger this in the meantime.
llvm-svn: 272258
This is made possible by removing an assert in llc that assumed
MIRParser::parseLLVMModule would exit on error. MIRParser's documentation states
that it returns null if a parsing error occurs, so there's no reason to assert.
We can instead just fall through to where the check for a module is performed
and exit if it is null.
This commit is part of the clean-up after r269655.
Fixes PR27770
Differential Revision: http://reviews.llvm.org/D20371
llvm-svn: 272254
If an immediate is only used in an AND node, it is possible that the immediate can be more optimally materialized when negated. If this is the case, we can negate the immediate and use a BIC instead;
int i(int a) {
return a & 0xfffffeec;
}
Used to produce:
ldr r1, [CONSTPOOL]
ands r0, r1
CONSTPOOL: 0xfffffeec
And now produces:
movs r1, #255
adds r1, #20 ; Less costly immediate generation
bics r0, r1
llvm-svn: 272251
It is possible for a field and a class to have the same name. In such
cases, performing lookup for the field might return a result set with
more than one entry. An overzealous assertion fired, causing us to
crash instead of using the non-class lookup result.
This fixes PR28060.
llvm-svn: 272247
Add support to the AArch64 IAS for the `.arch` directive. This allows the
assembly input to use architectural functionality in part of a file. This is
used in existing code like BoringSSL.
Resolves PR26016!
llvm-svn: 272241
We can safely rely on a NoWrap add recurrence causing UB down the road
only if we know the loop does not have a exit expressed in a way that is
opaque to ScalarEvolution (e.g. by a function call that conditionally
calls exit(0)).
I believe with this change PR28012 is fixed.
Note: I had to change some llvm-lit tests in LoopReroll, since it looks
like they were depending on this incorrect behavior.
llvm-svn: 272237
Peter Collingbourne