This is a cleanup patch for SSP support in LLVM. There is no functional change.
llvm.stackprotectorcheck is not needed, because SelectionDAG isn't
actually lowering it in SelectBasicBlock; rather, it adds check code in
FinishBasicBlock, ignoring the position where the intrinsic is inserted
(See FindSplitPointForStackProtector()).
llvm-svn: 265851
Summary:
In the context of http://wg21.link/lwg2445 C++ uses the concept of
'stronger' ordering but doesn't define it properly. This should be fixed
in C++17 barring a small question that's still open.
The code currently plays fast and loose with the AtomicOrdering
enum. Using an enum class is one step towards tightening things. I later
also want to tighten related enums, such as clang's
AtomicOrderingKind (which should be shared with LLVM as a 'C++ ABI'
enum).
This change touches a few lines of code which can be improved later, I'd
like to keep it as NFC for now as it's already quite complex. I have
related changes for clang.
As a follow-up I'll add:
bool operator<(AtomicOrdering, AtomicOrdering) = delete;
bool operator>(AtomicOrdering, AtomicOrdering) = delete;
bool operator<=(AtomicOrdering, AtomicOrdering) = delete;
bool operator>=(AtomicOrdering, AtomicOrdering) = delete;
This is separate so that clang and LLVM changes don't need to be in sync.
Reviewers: jyknight, reames
Subscribers: jyknight, llvm-commits
Differential Revision: http://reviews.llvm.org/D18775
llvm-svn: 265602
when GISel is not built.
The positive side effects are:
- We do not have to define dummy implementation
- We do not have to do weird gymnastic to avoid like issues (like
missing constructor or vtable for the base classes)
llvm-svn: 265570
Rework the access to GlobalISel APIs to contain how much of
the APIs we need to access for the final executable to build when
GlobalISel is not built.
This prevents massive usage of ifdefs in various places. Now, all the
GlobalISel ifdefs will be happing only in AArch64TargetMachine.cpp.
llvm-svn: 265567
This will avoid link-time error as the defautl constructor of RegisterBankInfo is
the only one available when GlobalISel is not built.
llvm-svn: 265549
AArch64InstrInfo::optimizeCompareInstr has a bug which causes generation of incorrect code (PR#27158).
The patch refactors the function to simplify reviewing the fix of the bug.
1. Function name ‘modifiesConditionCode’ is changed to ‘areCFlagsAccessedBetweenInstrs’
to reflect that the function can check modifying accesses, reading accesses or both.
2. Function ‘AArch64InstrInfo::optimizeCompareInstr’
- Documented the function
- Cmp_NZCV is DeadNZCVIdx to reflect that it is an operand index of dead NZCV
- The code for the case of substituting CmpInstr is put into separate
functions the main of them is ‘substituteCmpInstr’.
Differential Revision: http://reviews.llvm.org/D18609
llvm-svn: 265531
Bionic has a defined thread-local location for the stack protector
cookie. Emit a direct load instead of going through __stack_chk_guard.
llvm-svn: 265481
We can only perform a tail call to a callee that preserves all the
registers that the caller needs to preserve.
This situation happens with calling conventions like preserver_mostcc or
cxx_fast_tls. It was explicitely handled for fast_tls and failing for
preserve_most. This patch generalizes the check to any calling
convention.
Related to rdar://24207743
Differential Revision: http://reviews.llvm.org/D18680
llvm-svn: 265329
Summary:
This adds the same checks that were added in r264593 to all
target-specific passes that run after register allocation.
Reviewers: qcolombet
Subscribers: jyknight, dsanders, llvm-commits
Differential Revision: http://reviews.llvm.org/D18525
llvm-svn: 265313
Add support for the AArch64 .cpu directive. This is a slightly involved
directive since the parameter is actually a variable encoded string. The
general structure is:
<cpu>[[+-]<feature>]*
We now map some of the supported string names for features for internal
representation of feature flags. If we encounter one which we do not support,
bail out as we cannot validate the assembly any longer.
Resolves PR27010.
llvm-svn: 265240
When a fixup that can be resolved by the assembler is out of range, we should
report an error in the source, rather than crashing.
Differential Revision: http://reviews.llvm.org/D18402
llvm-svn: 265120
Summary:
This change will allow loads with imp-def to be clustered in machine-scheduler pass.
areMemAccessesTriviallyDisjoint() can also handle loads with imp-def.
Reviewers: mcrosier, jmolloy, t.p.northover
Subscribers: aemerson, rengolin, mcrosier, llvm-commits
Differential Revision: http://reviews.llvm.org/D18665
llvm-svn: 265051
This will become necessary in a subsequent change to make this method
merge adjacent stack adjustments, i.e. it might erase the previous
and/or next instruction.
It also greatly simplifies the calls to this function from Prolog-
EpilogInserter. Previously, that had a bunch of logic to resume iteration
after the call; now it just continues with the returned iterator.
Note that this changes the behaviour of PEI a little. Previously,
it attempted to re-visit the new instruction created by
eliminateCallFramePseudoInstr(). That code was added in r36625,
but I can't see any reason for it: the new instructions will obviously
not be pseudo instructions, they will not have FrameIndex operands,
and we have already accounted for the stack adjustment.
Differential Revision: http://reviews.llvm.org/D18627
llvm-svn: 265036
Summary:
This change will handle missing store pair opportunity where the first store
instruction stores zero followed by the non-zero store. For example, this change
will convert :
str wzr, [x8]
str w1, [x8, #4]
into:
stp wzr, w1, [x8]
Reviewers: jmolloy, t.p.northover, mcrosier
Subscribers: flyingforyou, aemerson, rengolin, mcrosier, llvm-commits
Differential Revision: http://reviews.llvm.org/D18570
llvm-svn: 265021
This is effectively NFC, minus the renaming of the options
(-cyclone-prefetch-distance -> -prefetch-distance).
The change was requested by Tim in D17943.
llvm-svn: 264806
If we can't handle a relocation type, report it as an error in the source,
rather than asserting. I've added a more descriptive message and a test for the
only cases of this that I've been able to trigger.
Differential Revision: http://reviews.llvm.org/D18388
llvm-svn: 264156
Avoid modifying other modules in `AArch64PromoteConstant` when the
constant is `ConstantData` (a horrible accident, I'm sure, caught by an
experimental follow-up to r261464).
Previously, this walked through all the users of a constant, but that
reaches into other modules when the constant doesn't depend transitively
on a `GlobalValue`! Since we're walking instructions anyway, just
modify the instructions we actually see.
As a drive-by, instead of storing `Use` and getting the instructions
again via `Use::getUser()` (which is not a constantant time lookup),
store `std::pair<Instruction, unsigned>`. Besides being cheaper, this
makes it easier to drop use-lists form `ConstantData` in the future.
(I threw this in because I was touching all the code anyway.)
Because the patch completely changes the traversal logic, it looks
like a rewrite of the pass, but the core logic is all the same (or
should be, minus the out-of-module changes). In other words, there
should be NFC as long as the LLVMContext only has a single Module.
I didn't think of a good way to test this, but I hope to submit a patch
eventually that makes walking these use-lists illegal/impossible.
llvm-svn: 263853
This patch adds unscaled loads and sign-extend loads to the TII
getMemOpBaseRegImmOfs API, which is used to control clustering in the MI
scheduler. This is done to create more opportunities for load pairing. I've
also added the scaled LDRSWui instruction, which was missing from the scaled
instructions. Finally, I've added support in shouldClusterLoads for clustering
adjacent sext and zext loads that too can be paired by the load/store optimizer.
Differential Revision: http://reviews.llvm.org/D18048
llvm-svn: 263819
Summary:
It can hurt performance to prefetch ahead too much. Be conservative for
now and don't prefetch ahead more than 3 iterations on Cyclone.
Reviewers: hfinkel
Subscribers: llvm-commits, mzolotukhin
Differential Revision: http://reviews.llvm.org/D17949
llvm-svn: 263772
Evandro Menezes