Dimitry Andric [Wed, 17 May 2017 19:46:49 +0000 (19:46 +0000)]
Reapply part of rL303015, fixing just the DynamicLibaryTest. Add
retrieval of the original argv[0] from the GoogleTest framework, so it
is more likely the correct main executable path is found.
Dimitry Andric [Wed, 17 May 2017 19:33:10 +0000 (19:33 +0000)]
Revert r303015, because it has the unintended side effect of breaking
driver-mode recognition in clang (this is because the sysctl method
always returns one and only one executable path, even for an executable
with multiple links):
Fix DynamicLibraryTest.cpp on FreeBSD and NetBSD
Summary:
After rL301562, on FreeBSD the DynamicLibrary unittests fail, because
the test uses getMainExecutable("DynamicLibraryTests", Ptr), and since
the path does not contain any slashes, retrieving the main executable
will not work.
Reimplement getMainExecutable() for FreeBSD and NetBSD using sysctl(3),
which is more reliable than fiddling with relative or absolute paths.
Also add retrieval of the original argv[] from the GoogleTest framework,
to use as a fallback for other OSes.
Reid Kleckner [Wed, 17 May 2017 18:16:17 +0000 (18:16 +0000)]
Re-land r303274: "[CrashRecovery] Use SEH __try instead of VEH when available"
We have to check gCrashRecoveryEnabled before using __try.
In other words, SEH works too well and we ended up recovering from
crashes in implicit module builds that we weren't supposed to. Only
libclang is supposed to enable CrashRecoveryContext to allow implicit
module builds to crash.
Reid Kleckner [Wed, 17 May 2017 17:02:16 +0000 (17:02 +0000)]
[CrashRecovery] Use SEH __try instead of VEH when available
Summary:
It avoids problems when other libraries raise exceptions. In particular,
OutputDebugString raises an exception that the debugger is supposed to
catch and suppress. VEH kicks in first right now, and that is entirely
incorrect.
Unfortunately, GCC does not support SEH, so I've kept the old buggy VEH
codepath around. We could fix it with SetUnhandledExceptionFilter, but
that is not per-thread, so a well-behaved library shouldn't set it.
Zachary Turner [Wed, 17 May 2017 16:39:06 +0000 (16:39 +0000)]
[CodeView] Simplify the use of visiting type records & streams.
There is often a lot of boilerplate code required to visit a type
record or type stream. The #1 use case is that you have a sequence
of bytes that represent one or more records, and you want to
deserialize each one, switch on it, and call a callback with the
deserialized record that the user can examine. Currently this
requires at least 6 lines of code:
This is done by having the deserialization happen internally inside
of the visitTypeRecord function. Since this is occasionally not
desirable, the function provides a 3rd parameter that can be used
to change this behavior.
Hopefully this can significantly reduce the barrier to entry
to using the visitation infrastructure.
Zachary Turner [Wed, 17 May 2017 15:49:45 +0000 (15:49 +0000)]
[BitVector] Add find_[first,last]_[set,unset]_in.
A lot of code is duplicated between the first_last and the
next / prev methods. All of this code can be shared if they
are implemented in terms of find_first_in(Begin, End) etc,
in which case find_first = find_first_in(0, Size) and find_next
is find_first_in(Prev+1, Size), with similar reductions for
the other methods.
Sanjay Patel [Wed, 17 May 2017 14:21:19 +0000 (14:21 +0000)]
[InstCombine] add isCanonicalPredicate() helper function and use it; NFCI
There should be a slight efficiency improvement from handling icmp/fcmp with one matcher and reducing duplicated code.
The larger motivation is that there are questions about how predicate canonicalization is handled, and the refactoring
should make it easier if we want to change any of that behavior.
1. As noted in the code comment, we've chosen 3 of the 16 FCMP preds as not canonical. Why those 3? It goes back to
rL32751 from what I can tell, but I'm not sure if there's a justification for that rule.
2. We currently do not canonicalize integer select conditions. Should we use the same rule that applies to branches
for selects?
3. We currently do canonicalize some FP select conditions, and those rules would conflict with the rule shown here.
Should one or both be changed?
No-functional-change-intended, but adding tests anyway because there's no coverage for most of the predicates.
The variables MinGPR/MinG8R were not updated properly when resetting the
offsets, which in the included testcase lead to saving the CR register
in the same location as R30.
George Rimar [Wed, 17 May 2017 12:10:51 +0000 (12:10 +0000)]
[DWARF] - Cleanup relocations proccessing.
RelocAddrMap was a pair of <width, address>, where width is relocation size (4/8/x, x < 8),
and width field was never used in code.
Relocations proccessing loop had checks for width field. Does not look like DWARF parser
should do that. There is probably no much sense to validate relocations during proccessing
them in parser.
Patch removes relocation's width relative code from DWARFContext.
Diana Picus [Wed, 17 May 2017 08:57:28 +0000 (08:57 +0000)]
[GlobalISel][TableGen] Fix handling of default operands
When looping through a destination pattern's operands to decide how many
default operands we need to introduce, we used to count the "expanded"
number of operands. So if one default operand would be rendered as 2
values, we'd count it as 2 operands, when in fact it needs to count as
only 1 operand regardless of how many values it expands to.
This turns out to be a problem only in some very specific cases, e.g.
when we have one operand with multiple default values followed by more
operands with default values (see the new test). In such a situation
we'd stop looping before looking at all the operands, and then error out
assuming that we don't have enough default operands to make up the
shortfall.
At the moment this only affects ARM.
The patch removes the loop counting default operands entirely and
assumes that we'll have to introduce values for any default operand that
we find (i.e. we're assuming it cannot be given as a child at all). It
also extracts the code for adding renderers for default operands into a
helper method.
Summary:
Debug info sections, (or non-SHF_ALLOC sections in general) should be
linked as if their load address was zero to emulate the behavior of the
static linker.
This bug was discovered because it was breaking lldb expression evaluation on
linux.
Jonas Paulsson [Wed, 17 May 2017 07:36:03 +0000 (07:36 +0000)]
Make sure -optimize-regalloc=false is used correctly by user.
Don't allow -optimize-regalloc=false with -regalloc given for anything other
than 'fast'. The other register allocators depend on the supporting passes
added by addOptimizedRegAlloc().
Max Kazantsev [Wed, 17 May 2017 04:09:14 +0000 (04:09 +0000)]
[SCEV] Always sort AddRecExprs from different loops by dominance
Sorting of AddRecExprs by loop nesting does not make sense since we only invoke
the CompareSCEVComplexity for AddRecExprs that are used by one SCEV. This
guarantees that there is always a dominance relationship between them. This
patch removes the sorting by nesting which is a dead code in current usage of
this function.
Gor Nishanov [Wed, 17 May 2017 03:09:22 +0000 (03:09 +0000)]
[coroutines] Handle spills before catchswitch
If we need to spill the result of the PHI instruction, we insert the spill after
all of the PHIs and EHPads, however, in a catchswitch block there is no
room to insert the spill. Make room by splitting away catchswitch into a separate
block.
Zachary Turner [Tue, 16 May 2017 22:50:32 +0000 (22:50 +0000)]
[Support] Ignore OutputDebugString exceptions in our crash recovery.
Since we use AddVectoredExceptionHandler, we get notified of
every exception that gets raised by a program. Sometimes these
are not necessarily errors though, and this can be especially
true when linking against a library that we have no control
over, and may raise an exception internally which it intends
to catch.
In particular, the Windows API OutputDebugString does exactly
this. It raises an exception inside of a __try / __except,
giving the debugger a chance to handle the exception to print
the message to the debug console.
But this doesn't interoperate nicely with our vectored exception
handler, which just sees another exception and decides that we
need to terminate the program.
Add a special case for this so that we ignore ODS exceptions
and continue normally.
Note that a better fix is to simply not use vectored exception
handlers and use SEH instead, but given that MinGW doesn't support
SEH, this is the only solution for MinGW.
Adrian McCarthy [Tue, 16 May 2017 22:11:25 +0000 (22:11 +0000)]
Add test for FixedStreamArrayIterator::operator->
The operator-> implementation comes from iterator_facade_base, so it should
just work given that the iterator has a tested operator*. But r302257 showed
that required careful handling of for the const qualifier. This patch ensures
the fix in r302257 doesn't regress.
Sanjay Patel [Tue, 16 May 2017 21:51:04 +0000 (21:51 +0000)]
[InstSimplify] add folds for constant mask of value shifted by constant
We would eventually catch these via demanded bits and computing known bits in InstCombine,
but I think it's better to handle the simple cases as soon as possible as a matter of efficiency.
This fold allows further simplifications based on distributed ops transforms. eg:
%a = lshr i8 %x, 7
%b = or i8 %a, 2
%c = and i8 %b, 1
InstSimplify can directly fold this now:
%a = lshr i8 %x, 7
Easwaran Raman [Tue, 16 May 2017 21:18:09 +0000 (21:18 +0000)]
[Inliner] Do not mix callsite and callee hotness based updates.
Update threshold based on callee's hotness only when BFI is not available.
Otherwise use only callsite's hotness. This makes it easier to reason about
hotness related threshold updates.
The lowering pipeline is:
llvm.ppc.cfence in IR -> PPC::CFENCE8 in isel -> Actual instructions in
expandPostRAPseudo.
The reason why expandPostRAPseudo is chosen is because previous passes
are likely eliminating instructions like cmpw 3, 3 (early CSE) and bne-
7, .+4 (some branch pass(s)).
Easwaran Raman [Tue, 16 May 2017 20:14:39 +0000 (20:14 +0000)]
Add hasProfileSummary and has{Sample|Instrumentation}Profile methods
ProfileSummaryInfo already checks whether the module has sample profile
in determining profile counts. This will also be useful in inliner to
clean up threshold updates.
Nirav Dave [Tue, 16 May 2017 19:43:56 +0000 (19:43 +0000)]
Elide stores which are overwritten without being observed.
Summary:
In SelectionDAG, when a store is immediately chained to another store
to the same address, elide the first store as it has no observable
effects. This is causes small improvements dealing with intrinsics
lowered to stores.
Test notes:
* Many testcases overwrite store addresses multiple times and needed
minor changes, mainly making stores volatile to prevent the
optimization from optimizing the test away.
* Many X86 test cases optimized out instructions associated with
associated with va_start.
* Note that test_splat in CodeGen/AArch64/misched-stp.ll no longer has
dependencies to check and can probably be removed and potentially
replaced with another test.
Sanjay Patel [Tue, 16 May 2017 16:30:46 +0000 (16:30 +0000)]
[InstCombine] add motivational comment for tests; NFC
The referenced tests are derived from:
https://bugs.llvm.org/show_bug.cgi?id=32791
and:
https://reviews.llvm.org/D33172
The motivation for including negative tests may not be clear, so I'm adding an explanatory comment here.
In the post-commit thread for r303133:
http://lists.llvm.org/pipermail/llvm-commits/Week-of-Mon-20170515/453793.html
...it was mentioned that we don't want to add redundant tests. This is a valid point. But in this case,
we have a patch under review (D33172) that demonstrates that no existing regression tests are affected by
a proposed code change, but these are. Therefore, I think these tests have value not visible in any
existing regression tests regardless of whether they show a transform.
[AMDGPU] Cache live-ins and register pressure in scheduler
Using LIS can be quite expensive, so caching of calculated region
live-ins and pressure is implemented. It does two things:
1. Caches the info for the second stage when we schedule with
decreased target occupancy.
2. Tracks the basic block from top to bottom thus eliminating the
need to scan whole register file liveness at every region split
in the middle of the block.
The scheduling is now done in 3 stages instead of two, with the first
one being really a no-op and only used to collect scheduling regions
as sent by the scheduler driver.
There is no functional change to the current behavior, only compilation
speed is affected. In general computeBlockPressure() could be simplified
if we switch to backward RP tracker, because scheduler sends regions
within a block starting from the last upward. We could use a natural
order of upward tracker to seamlessly change between regions of the same
block, since live reg set of a previous tracked region would become a
live-out of the next region. That however requires fixing upward tracker
to properly account defs and uses of the same instruction as both are
contributing to the current pressure. When we converge on the produced
pressure we should be able to switch between them back and forth. In
addition, backward tracker is less expensive as it uses LIS in recede
less often than forward uses it in advance.
At the moment the worst known case compilation time has improved from 26
minutes to 8.5.
Lama Saba [Tue, 16 May 2017 16:01:36 +0000 (16:01 +0000)]
[X86] Replace slow LEA instructions in X86
According to Intel's Optimization Reference Manual for SNB+:
" For LEA instructions with three source operands and some specific situations, instruction latency has increased to 3 cycles, and must
dispatch via port 1:
- LEA that has all three source operands: base, index, and offset
- LEA that uses base and index registers where the base is EBP, RBP,or R13
- LEA that uses RIP relative addressing mode
- LEA that uses 16-bit addressing mode "
This patch currently handles the first 2 cases only.
[AMDGPU] Turn register pressure estimation into forward tracker
This factors register pressure estimation mechanism from the
GCNSchedStrategy into the forward tracker to unify interface
with other strategies and expose it to other interested phases.
Gor Nishanov [Tue, 16 May 2017 14:11:39 +0000 (14:11 +0000)]
[coroutines] Handle unwind edge splitting
Summary:
RewritePHIs algorithm used in building of CoroFrame inserts a placeholder
```
%placeholder = phi [%val]
```
on every edge leading to a block starting with PHI node with multiple incoming edges,
so that if one of the incoming values was spilled and need to be reloaded, we have a
place to insert a reload. We use SplitEdge helper function to split the incoming edge.
SplitEdge function does not deal with unwind edges comping into a block with an EHPad.
This patch adds an ehAwareSplitEdge function that can correctly split the unwind edge.
For landing pads, we clone the landing pad into every edge block and replace the original
landing pad with a PHI collection the values from all incoming landing pads.
For WinEH pads, we keep the original EHPad in place and insert cleanuppad/cleapret in the
edge blocks.
George Rimar [Tue, 16 May 2017 12:30:59 +0000 (12:30 +0000)]
[DWARF] - Use DWARFAddressRange struct instead of uint64_t pair for DWARFAddressRangesVector.
Recommit of r303159 "[DWARF] - Use DWARFAddressRange struct instead of uint64_t pair for DWARFAddressRangesVector"
All places were shitched to use DWARFAddressRange now.
George Rimar [Tue, 16 May 2017 12:05:03 +0000 (12:05 +0000)]
Revert r303159 "[DWARF] - Use DWARFAddressRange struct instead of uint64_t pair for DWARFAddressRangesVector."
Something went wrong, it broke BB.
http://green.lab.llvm.org/green//job/clang-stage1-cmake-RA-incremental_build/38477/consoleFull#-200034420049ba4694-19c4-4d7e-bec5-911270d8a58c
James Henderson [Tue, 16 May 2017 09:43:21 +0000 (09:43 +0000)]
[LTO] Print time-passes information at conclusion of LTO codegen
The information collected when requested by -time-passes is only printed when
llvm_shutdown is called at the moment. This means that when linking against the LTO
library dynamically and using the C interface, it is not possible to see the timing
information, because llvm_shutdown cannot be called. This change modifies the LTO
code generation functions for both regular LTO and thin LTO to explicitly print and
reset the timing information.
I have tested that this works with our proprietary linker. However, as this relies
on a specific method of building and linking against the LTO library, I'm not sure
how or if this can be tested in the LLVM testsuite.
Max Kazantsev [Tue, 16 May 2017 07:27:06 +0000 (07:27 +0000)]
[SCEV] Fix sorting order for AddRecExprs
The existing sorting order in defined CompareSCEVComplexity sorts AddRecExprs
by loop depth, but does not pay attention to dominance of loops. This can
lead us to the following buggy situation:
for (...) { // loop1
op1 = {A,+,B}
}
for (...) { // loop2
op2 = {A,+,B}
S = add op1, op2
}
In this case there is no guarantee that in operand list of S the op2 comes
before op1 (loop depth is the same, so they will be sorted just
lexicographically), so we can incorrectly treat S as a recurrence of loop1,
which is wrong.
This patch changes the sorting logic so that it places the dominated recs
before the dominating recs. This ensures that when we pick the first recurrency
in the operands order, it will be the bottom-most in terms of domination tree.
The attached test set includes some tests that produce incorrect SCEV
estimations and crashes with oldlogic.
IR: Give function GlobalValue::getRealLinkageName() a less misleading name: dropLLVMManglingEscape().
This function gives the wrong answer on some non-ELF platforms in some
cases. The function that does the right thing lives in Mangler.h. To try to
discourage people from using this function, give it a different name.
[ShrinkWrapping] Handle restores on no-return paths
Shrink-wrapping uses post-dominators to find a restore point that
post-dominates all the uses of CSR / stack.
The way dominator trees are modeled in LLVM today is that unreachable
blocks are not present in a generic dominator tree, so, an unreachable node is
dominated by anything: include/llvm/Support/GenericDomTree.h:467.
Since for post-dominators, a no-return block is considered
"unreachable", calling findNearestCommonDominator on an unreachable node
A and a non-unreachable node B, will return B, which can be false. If we
find such node, we bail out since there is no good restore point
available.