Patterns with add/sub combos can be improved using
'not' ops. This is better for analysis and may lead
to follow-on transforms because 'xor' and 'add' are
commutative/associative. It can also help codegen.
Matt Arsenault [Sat, 28 Jul 2018 14:11:34 +0000 (14:11 +0000)]
AMDGPU: Stop wasting argument registers with v3i32/v3f32
SelectionDAGBuilder widens v3i32/v3f32 arguments to
to v4i32/v4f32 which consume an additional register.
In addition to wasting argument space, this produces extra
instructions since now it appears the 4th vector component has
a meaningful value to most combines.
This patch adds support for instructions that partition a predicate
based on data-dependent termination conditions in a loop.
BRKA Break after the first true condition
BRKAS Break after the first true condition, setting condition flags
BRKB Break before the first true condition
BRKBS Break before the first true condition, setting condition flags
BRKPA Break after the first true condition, propagating from the
previous partition
BRKPAS Break after the first true condition, propagating from the
previous partition, setting condition flags
BRKPB Break before the first true condition, propagating from the
previous partition
BRKPBS Break before the first true condition, propagating from the
previous partition, setting condition flags
BRKN Propagate break to next partition
BKRNS Propagate break to next partition, setting condition flags
David Green [Sat, 28 Jul 2018 08:20:10 +0000 (08:20 +0000)]
[GlobalOpt] Test array indices inside structs for out-of-bounds accesses
We now, from clang, can turn arrays of
static short g_data[] = {16, 16, 16, 16, 16, 16, 16, 16, 0, 0, 0, 0, 0, 0, 0, 0};
into structs of the form
@g_data = internal global <{ [8 x i16], [8 x i16] }> ...
GlobalOpt will incorrectly SROA it, not realising that the access to the first
element may overflow into the second. This fixes it by checking geps more
thoroughly.
I believe this makes the globalsra-partial.ll test case invalid as the %i value
could be out of bounds. I've re-purposed it as a negative test for this case.
Erik Pilkington [Sat, 28 Jul 2018 04:06:30 +0000 (04:06 +0000)]
[demangler] Fix an oss-fuzz bug from r338138
Stack overflow on invalid. While collapsing references, we were skipping over a
cycle check in ForwardTemplateReference leading to a stack overflow. This commit
fixes the problem by duplicating the cycle check in ReferenceType.
Jakub Kuderski [Sat, 28 Jul 2018 00:54:07 +0000 (00:54 +0000)]
[Dominators] Make applyUpdate's documentation less confusing [NFC]
Summary:
It was pointed out by @chandlerc that it's not clear whether both applyUpdates and insert/deleteEdge can be used to perform multiple updates.
IMO, the confusing part was that the comment above applyUpdates made a comparison of expected update time between calling it and calling insert/deleteEdge multiple times. It's generally not possible to safely call insert/deleteEdge multiple times, which documentation for each of the 3 functions warns about, so the whole comparison makes very little sense. On top of that, the comment is already lengthy, so I think it's best to just get rid of this comparison.
[SimpleLoopUnswitch] Fix DT updates for trivial branch unswitching.
Summary:
Fixing 2 issues with the DT update in trivial branch switching, though I don't have a case where DT update fails.
1. After splitting ParentBB->UnswitchedBB edge, new edges become: ParentBB->LoopExitBB->UnswitchedBB, so remove ParentBB->LoopExitBB edge.
2. AFAIU, for multiple CFG changes, DT should be updated using batch updates, vs consecutive addEdge and removeEdge calls.
[WebAssembly] Added default stack-only instruction mode for MC.
Summary:
Moved Explicit Locals pass to last.
Made that pass obligatory.
Made it convert from register to stack based instructions, and removed the registers.
Fixes to related code that was expecting register based instructions.
Added the correct testing flag to all tests, depending on what the
format they were expecting so far.
Translated one test to stack format as example: reg-stackify-stack.ll
tested:
llvm-lit -v `find test -name WebAssembly`
unittests/MC/*
Recommit "Enable MachineOutliner by default under -Oz for AArch64"
Fixed the ASAN failure from before in r338148, so recommiting.
This patch enables the MachineOutliner by default in AArch64 under -Oz.
The MachineOutliner offers around a 4.5% improvement on the current -Oz code
size improvements.
We have done work into improving the debuggability of outlined code, so that
users of -Oz won't be surprised by the optimization. We have also been executing
the LLVM test suite and common external tests such as the SPEC suites
continuously with no issue. The outliner has a low compile-time overhead of
roughly 1%. At this point, the outliner would be a really good addition to the
-Oz pass pipeline!
[AArch64, PowerPC, x86] add more signbit math tests; NFC
The tests with a constant sub operand were added with rL338143,
but the potential transform doesn't have that requirement, so
adding more tests with variable operands.
[ARM] Add new target feature to fuse literal generation
This feature enables the fusion of such operations on Cortex A57 and Cortex
A72, as recommended in their Software Optimisation Guides, sections 4.14 and
4.11, respectively.
*** Bad machine code: Explicit definition marked as use ***
- function: cal_align1
- basic block: %bb.0 entry (0x47edd98)
- instruction: LDB $r3, $r2, 0
- operand 0: $r3
This is because RegState info was missing for ScratchReg inside
expandMEMCPY. This caused incomplete register usage information to
MachineInstr verifier which then would complain as there could be potential
code-gen issue if the complained MachineInstr is used in place where
register usage information matters even though the memcpy expanding is not
in such case as it happens at the last stage of IR optimization pipeline.
We should always specify those register usage information which compiler
couldn't deduct automatically whenever we add a hardware register manually.
Reported-by: Builder llvm-clang-x86_64-expensive-checks-win Build #11261 Signed-off-by: Jiong Wang <jiong.wang@netronome.com> Reviewed-by: Yonghong Song <yhs@fb.com>
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@338134 91177308-0d34-0410-b5e6-96231b3b80d8
Enable MachineOutliner by default under -Oz for AArch64
This patch enables the MachineOutliner by default in AArch64 under -Oz.
The MachineOutliner offers around a 4.5% improvement on the current -Oz code
size improvements.
We have done work into improving the debuggability of outlined code, so that
users of -Oz won't be surprised by the optimization. We have also been executing
the LLVM test suite and common external tests such as the SPEC suites
continuously with no issue. The outliner has a low compile-time overhead of
roughly 1%. At this point, the outliner would be a really good addition to the
-Oz pass pipeline!
This patch adds support for various integer reduction operations:
SADDV signed add reduction to scalar
UADDV unsigned add reduction to scalar
SMAXV signed maximum reduction to scalar
SMINV signed minimum reduction to scalar
UMAXV unsigned maximum reduction to scalar
UMINV unsigned minimum reduction to scalar
ANDV logical AND reduction to scalar
ORV logical OR reduction to scalar
EORV logical EOR reduction to scalar
The reduction is predicated, e.g.
smaxv s0, p0, z1.s
performs a signed maximum reduction on active elements in z1,
and stores the (signed max value) result in s0.
[AArch64][SVE] Asm: Predicated floating point reductions.
This patch adds support for various floating-point
reduction operations:
FADDA strictly-ordered add reduction, accumulating in scalar
FADDV recursive add reduction to scalar
FMAXV recursive max reduction to scalar
FMINV recursive min reduction to scalar
FMAXNMV recursive max number reduction to scalar
FMINNMV recursive min number reduction to scalar
The reduction is predicated, e.g.
fadda d0, p0, d0, z1.d
performs the add-reduction in strict order on active elements
in z1, accumulating into d0.
faddv d0, p0, z1.d
performs the add-reduction (not in strict order)
on active elements in z1, storing the result in d0.
This patch adds support for transcendental acceleration
instructions 'FEXPA' (exponential accelerator) and 'FTSSEL'
(trigonometric select coefficient).
Philip Pfaffe [Fri, 27 Jul 2018 10:57:51 +0000 (10:57 +0000)]
[CMake] Followup for r337366: Only export LLVM_LINK_LLVM_DYLIB if it's set to ON
Summary:
As it was, always exporting LLVM_LINK_LLVM_DYLIB caused out-of-tree
clients to lose the ability to link against the dylib, even if in-tree tools did
not. By only exporting the setting if it is enabled, out-of-tree clients get the
correct default, but may still choose if they can.
The tests with constants show a missing optimization.
Analysis for adds is better than subs, so this can also
help with other transforms. And codegen is better with
adds for targets like x86 (destructive ops, no sub-from).
Max Kazantsev [Fri, 27 Jul 2018 09:43:39 +0000 (09:43 +0000)]
[SimplifyIndVar] Canonicalize comparisons to unsigned while eliminating truncs
This is a follow-up for the patch rL335020. When we replace compares against
trunc with compares against wide IV, we can also replace signed predicates with
unsigned where it is legal.
[InstSimplify] tests for D48828: fold extraction from std::pair
This commit includes unit tests for D48828, which enhances InstSimplify to enable jump threading with a method whose return type is std::pair<int, bool> or std::pair<bool, int>.
I am going to commit the actual transformation later.
[X86] Remove an unnecessary 'if' that prevented treating INT64_MAX and -INT64_MAX as power of 2 minus 1 in the multiply expansion code.
Not sure why they were being explicitly excluded, but I believe all the math inside the if works. I changed the absolute value to be uint64_t instead of int64_t so INT64_MIN+1 wouldn't be signed wrap.
Bob Haarman [Fri, 27 Jul 2018 05:40:29 +0000 (05:40 +0000)]
[LTO] Don't internalize declarations
Summary:
Some links were failing with "Global is external, but doesn't have
external or weak linkage!" in ThinLTO builds with debug
information. This happened when we elide the body of a global that is
referenced by debug info. This results in a declaration, which we
would then internalize - but declarations cannot be internal. This
change avoids the problem by not internalizing these declarations.
[X86] Add matching for another pattern of PMADDWD.
Summary:
This is the pattern you get from the loop vectorizer for something like this
int16_t A[1024];
int16_t B[1024];
int32_t C[512];
void pmaddwd() {
for (int i = 0; i != 512; ++i)
C[i] = (A[2*i]*B[2*i]) + (A[2*i+1]*B[2*i+1]);
}
In this case we will have (add (mul (build_vector), (build_vector)), (mul (build_vector), (build_vector))). This is different than the pattern we currently match which has the build_vectors between an add and a single multiply. I'm not sure what C code would get you that pattern.
[X86] When removing sign extends from gather/scatter indices, make sure we handle UpdateNodeOperands finding an existing node to CSE with.
If this happens the operands aren't updated and the existing node is returned. Make sure we pass this existing node up to the DAG combiner so that a proper replacement happens. Otherwise we get stuck in an infinite loop with an unoptimized node.
[SelectionDAGBuilder] Add masked loads to PendingLoads rather than calling DAG.setRoot.
Masked loads are calling DAG.getRoot rather than calling SelectionDAGBuilder::getRoot, which means the PendingLoads weren't emptied to update the root and create any needed TokenFactor. So it would be incorrect to call setRoot for the masked load.
This patch instead adds the masked load to PendingLoads so that the root doesn't get update until a store or scatter or something happens.. Alternatively, we could call SelectionDAGBuilder::getRoot before it, but that would create unnecessary serialization.
[InstrProf] Use comdats on COFF for available_externally functions
Summary:
r262157 added ELF-specific logic to put a comdat on the __profc_*
globals created for available_externally functions. We should be able to
generalize that logic to all object file formats that support comdats,
i.e. everything other than MachO. This fixes duplicate symbol errors,
since on COFF, linkonce_odr doesn't make the symbol weak.
Wolfgang Pieb [Thu, 26 Jul 2018 22:48:52 +0000 (22:48 +0000)]
[DWARF v5] Reposting r337981, which was reverted in r337997 due to a test failure in debuginfo_tests.
The test failure was caused by the compiler not emitting a __debug_ranges section with DWARF 4 and
earlier when no ranges are needed. The test checks for the existence regardless.
[MS Demangler] Properly handle function parameter back-refs.
Properly demangle function parameter back-references.
Previously we treated lists of function parameters and template
parameters the same. There are some important differences with regards
to back-references, and some less important differences regarding which
characters can appear before or after the name.
The important differences are that with a given type T, all instances of
a function parameter list share the same global back-ref table.
Specifically, if X and Y are function pointers, then there are 3
entities in the declaration X func(Y) which all affect and are affected
by the master parameter back-ref table:
1) The parameter list of X's function type
2) the parameter list of func itself
3) The parameter list of Y's function type.
The previous code would create a back-reference table that was local to
a single parameter list, so it would not be shared across parameter
lists.
This was discovered when porting ms-back-references.test from clang's
mangling tests. All of these tests should now pass with the new changes.
In doing so, I split the function for parsing template and function
parameters into two separate functions. This makes the template
parameter list parsing code in particular very small and easy to
understand now.
[SCEV] Don't expand Wrap predicate using inttoptr in ni addrspaces
Summary:
In non-integral address spaces, we're not allowed to introduce inttoptr/ptrtoint
intrinsics. Instead, we need to expand any pointer arithmetic as geps on the
base pointer. Luckily this is a common task for SCEV, so all we have to do here
is hook up the corresponding helper function and add test case.
[SCEV] Add an expandAddToGEP overload for a single operand. NFC.
Only wanting to pass a single SCEV operand to use as the offset of
the GEP is a common operation. Right now this requires creating a
temporary stack array at every call site. Add an overload
that encapsulates that pattern and simplify the call sites.
Suggested-By: sanjoy (in https://reviews.llvm.org/D49832)
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@338072 91177308-0d34-0410-b5e6-96231b3b80d8
Tim Renouf [Thu, 26 Jul 2018 21:27:34 +0000 (21:27 +0000)]
[RegisterCoalescer] Fixed inconsistent followCopyChain with subreg
Summary:
The behavior of followCopyChain with a subreg depends on the order in
which subranges appear in a live interval, which is bad.
This commit fixes that, and allows the copy chain to continue only if
all matching subranges that are not undefined take us to the same def.
I don't have a test for this; the reproducer I had on my branch with
various other local changes does not reproduce the problem on upstream
llvm. Also that reproducer was an ll test; attempting to convert it to a
mir test made the subranges appear in a different order and hid the
problem.
However I would argue that the old behavior was obviously wrong
and needs fixing.
[DebugInfo] LowerDbgDeclare: Add derefs when handling CallInst users
LowerDbgDeclare inserts a dbg.value before each use of an address
described by a dbg.declare. When inserting a dbg.value before a CallInst
use, however, it fails to append DW_OP_deref to the DIExpression.
The DW_OP_deref is needed to reflect the fact that a dbg.value describes
a source variable directly (as opposed to a dbg.declare, which relies on
pointer indirection).
This patch adds in the DW_OP_deref where needed. This results in the
correct values being shown during a debug session for a program compiled
with ASan and optimizations (see https://reviews.llvm.org/D49520). Note
that ConvertDebugDeclareToDebugValue is already correct -- no changes
there were needed.
One complication is that SelectionDAG is unable to distinguish between
direct and indirect frame-index (FRAMEIX) SDDbgValues. This patch also
fixes this long-standing issue in order to not regress integration tests
relying on the incorrect assumption that all frame-index SDDbgValues are
indirect. This is a necessary fix: the newly-added DW_OP_derefs cannot
be lowered properly otherwise. Basically the fix prevents a direct
SDDbgValue with DIExpression(DW_OP_deref) from being dereferenced twice
by a debugger. There were a handful of tests relying on this incorrect
"FRAMEIX => indirect" assumption which actually had incorrect
DW_AT_locations: these are all fixed up in this patch.
Testing:
- check-llvm, and an end-to-end test using lldb to debug an optimized
program.
- Existing unit tests for DIExpression::appendToStack fully cover the
new DIExpression::append utility.
- check-debuginfo (the debug info integration tests)
This converts the arg qualifier mangling tests from
clang/CodeGenCXX/mangle-ms-arg-qualifiers.cpp to demangling tests.
Most tests already pass, so this patch doesn't come with any
functional change, just the addition of new tests. The few tests
that don't pass are left in with a FIXME label so that they don't
run but serve as documentation about what still doesn't work.
None of these tests pass yet so they are commented out, but I'm
adding them with a FIXME label so that they don't get lost when
copying tests over from clang's mangling tests. Currently these
tests are all commented out.
[MS Demangler] Demangle pointers to member functions.
After this patch, we can now properly demangle pointers to member
functions. The calling convention is located in the wrong place,
but this will be fixed in a followup since it also affects non
member function pointers.
Martin Storsjo [Thu, 26 Jul 2018 20:11:26 +0000 (20:11 +0000)]
[MC] Add support for the .rva assembler directive for COFF targets
Even though gas doesn't document it, it has been supported there for
a very long time.
This produces the 32 bit relative virtual address (aka image relative
address) for a given symbol. ".rva foo" is essentially equal to
".long foo@imgrel".
Stephen Hines [Thu, 26 Jul 2018 20:05:31 +0000 (20:05 +0000)]
Handle the lack of a symbol table correctly.
Summary:
These two cases will trigger a dereference on a nullptr, since the
SymbolTable can be nonexistent for a given library, in addition to just
being empty.
Scott Linder [Thu, 26 Jul 2018 19:47:51 +0000 (19:47 +0000)]
[AMDGPU] Fix VGPR spills where offset doesn't fit in 12 bits
Scale the offset of VGPR spills by the wave size when it cannot fit in the
12-bit offset immediate field and so is added to the soffset SGPR. This
accounts for hardware swizzling of scratch memory.
Ana Pazos [Thu, 26 Jul 2018 17:49:43 +0000 (17:49 +0000)]
[RISCV] Add support for _interrupt attribute
- Save/restore only registers that are used.
This includes Callee saved registers and Caller saved registers
(arguments and temporaries) for integer and FP registers.
- If there is a call in the interrupt handler, save/restore all
Caller saved registers (arguments and temporaries) and all FP registers.
- Emit special return instructions depending on "interrupt"
attribute type.
Based on initial patch by Zhaoshi Zheng.
MacroFusion: Fix macro fusion with ExitSU failing in top-down scheduling
When fusing instructions A and B, we must add all predecessors of B as
predecessors of A to avoid instructions getting scheduling in between.
There is a special case involving ExitSU: Every other node must be
scheduled before it by design and we don't need to make this explicit in
the graph, however when fusing with a different node we need to schedule
every othere node before the fused node too and we need to make this
explicit now: This patch adds a dependency from the fused node to all
roots in the graph.
[DEBUGINFO, NVPTX] Emit correct debug information for local variables.
Summary:
NVPTX target dos not use register-based frame information. Instead it
relies on the artificial local_depot that is used instead of the frame
and the data for variables must be emitted relatively to this
local_depot.
[InstCombine] add tests for udiv with common factor; NFC
This fold is mentioned in PR38239:
https://bugs.llvm.org/show_bug.cgi?id=38239
The general case probably belongs in -reassociate, but given that we do
basic reassociation optimizations similar to this in instcombine already,
we might as well be consistent within instcombine and handle this pattern?
Michael Kruse [Thu, 26 Jul 2018 15:31:41 +0000 (15:31 +0000)]
[ADT] Replace std::isprint by llvm::isPrint.
The standard library functions ::isprint/std::isprint have platform-
and locale-dependent behavior which makes LLVM's output less
predictable. In particular, regression tests my fail depending on the
implementation of these functions.
Implement llvm::isPrint in StringExtras.h with a standard behavior and
replace all uses of ::isprint/std::isprint by a call it llvm::isPrint.
The function is inlined and does not look up language settings so it
should perform better than the standard library's version.
Such a replacement has already been done for isdigit, isalpha, isxdigit
in r314883. gtest does the same in gtest-printers.cc using the following
justification:
// Returns true if c is a printable ASCII character. We test the
// value of c directly instead of calling isprint(), which is buggy on
// Windows Mobile.
inline bool IsPrintableAscii(wchar_t c) {
return 0x20 <= c && c <= 0x7E;
}
Similar issues have also been encountered by Julia:
https://github.com/JuliaLang/julia/issues/7416
I noticed the problem myself when on Windows isprint('\t') started to
evaluate to true (see https://stackoverflow.com/questions/51435249) and
thus caused several unit tests to fail. The result of isprint doesn't
seem to be well-defined even for ASCII characters. Therefore I suggest
to replace isprint by a platform-independent version.
Pavel Labath [Thu, 26 Jul 2018 14:36:07 +0000 (14:36 +0000)]
dwarfgen: Add support for generating the debug_str_offsets section, take 3
Previous version of this patch failed on darwin targets because of
different handling of cross-debug-section relocations. This fixes the
tests to emit the DW_AT_str_offsets_base attribute correctly in both
cases. Since doing this is a non-trivial amount of code, and I'm going
to need it in more than one test, I've added a helper function to the
dwarfgen DIE class to do it.
Original commit message follows:
The motivation for this is D49493, where we'd like to test details of
debug_str_offsets behavior which is difficult to trigger from a
traditional test.
This adds the plubming necessary for dwarfgen to generate this section.
The more interesting changes are:
- I've moved emitStringOffsetsTableHeader function from DwarfFile to
DwarfStringPool, so I can generate the section header more easily from
the unit test.
- added a new addAttribute overload taking an MCExpr*. This is used to
generate the DW_AT_str_offsets_base, which links a compile unit to the
offset table.
I've also added a basic test for reading and writing DW_form_strx forms.
Apparently, the issue with dsymutil update functionality on Windows was
that Windows doesn't like dsymutil renaming files that have open handles
to them. This disables the new accelerator test and updates the comment
in the other two test.
We should be able to enable the tests again once we updated the
implementation to use TempFile::keep() to keep the temporary files in
MachOUtils.
A big thank you to Jeremy Morse from Sony for figuring this out and
bringing it to my attention.
Luke Cheeseman [Thu, 26 Jul 2018 14:00:50 +0000 (14:00 +0000)]
Enable some pointer authentication instructions for aarch64 v8a targets
- Some of the v8.3 pointer authentication instruction inhabit the Hint space
- These instructions can be assembled to hint instructions which act as NOP instructions prior to v8.3
- This patch permits using the hint instructions for all v8a targets
- Also, correct the RETA{A,B} instructions to match the instruction attributes of RET (set isTerminator and isBarrier)
James Henderson [Thu, 26 Jul 2018 13:22:07 +0000 (13:22 +0000)]
Fix raw_fd_ostream::write_impl hang with large output
On Windows when raw_fd_ostream::write_impl calls write, a 32 bit input
is required for character count. As a variable with size_t is used for
this argument on x64 integral demotion occurs. In the case of large
files an infinite loop follows.
See PR37926.
This fix allows the output of files larger than previous int32 limit.
Pavel Labath [Thu, 26 Jul 2018 13:16:06 +0000 (13:16 +0000)]
dwarfgen: Don't create an AsmPrinter with an invalid ObjFile lowering
The AsmPrinter created in the tests contained an uninitialized
TargetLoweringObjectFile. Things mostly worked regardless, because we
used a separate instance of that class to specify sections to emit.
This rearanges the object construction order so that we can avoid
creating two lowering objects. Instead, we properly initialize the
object in the AsmPrinter, and have the DWARF generator store a pointer
to it.