Heejin Ahn [Thu, 10 Jan 2019 23:12:07 +0000 (23:12 +0000)]
[WebAssembly] Fix stack pointer store check in RegStackify
Summary:
We now use __stack_pointer global and global.get/global.set instruction.
This fixes the checking routine for stack_pointer writes accordingly.
This also fixes the existing __stack_pointer test in reg-stackify.ll:
That test used to pass not because of __stack_pointer clashes but
because the function `stackpointer_callee` was not marked as `readnone`,
so it was assumed to possibly write to memory arbitraily, and
`global.set` instruction was marked as `mayStore` in the .td definition,
so they were identified as intervening writes. After we added `readnone`
to its attribute, this test fails without this patch.
[MSP430] Minor fixes/improvements for assembler/disassembler
* Teach AsmParser to recognize @rn in distination operand as 0(rn).
* Do not allow Disassembler decoding instructions that have size more
than a number of input bytes.
* Fix UB in MSP430MCCodeEmitter.
Alina Sbirlea [Thu, 10 Jan 2019 21:47:15 +0000 (21:47 +0000)]
[MemorySSA] Disable checkClobberSanity for SkipSelfWalker.
Sanity will fail for this, since we're exploring getting a clobber
further than the sanity check expects.
Ideally we need to teach the sanity check to differentiate between the
two walkers based on the SkipSelf bool in the query.
Matt Davis [Thu, 10 Jan 2019 19:56:03 +0000 (19:56 +0000)]
[GVN] Update BlockRPONumber prior to use.
Summary:
The original patch addressed the use of BlockRPONumber by forcing a sequence point when accessing that map in a conditional. In short we found cases where that map was being accessed with blocks that had not yet been added to that structure. For context, I've kept the wall of text below, to what we are trying to fix, by always ensuring a updated BlockRPONumber.
== Backstory ==
I was investigating an ICE (segfault accessing a DenseMap item). This failure happened non-deterministically, with no apparent reason and only on a Windows build of LLVM (from October 2018).
After looking into the crashes (multiple core files) and running DynamoRio, the cores and DynamoRio (DR) log pointed to the same code in `GVN::performScalarPRE()`. The values in the map are unsigned integers, the keys are `llvm::BasicBlock*`. Our test case that triggered this warning and periodic crash is rather involved. But the problematic line looks to be:
GVN.cpp: Line 2197
```
if (BlockRPONumber[P] >= BlockRPONumber[CurrentBlock] &&
```
To test things out, I cooked up a patch that accessed the items in the map outside of the condition, by forcing a sequence point between accesses. DynamoRio stopped warning of the issue, and the test didn't seem to crash after 1000+ runs.
My investigation was on an older version of LLVM, (source from October this year). What it looks like was occurring is the following, and the assembly from the latest pull of llvm in December seems to confirm this might still be an issue; however, I have not witnessed the crash on more recent builds. Of course the asm in question is generated from the host compiler on that Windows box (not clang), but it hints that we might want to consider how we access the BlockRPONumber map in this conditional (line 2197, listed above). In any case, I don't think the host compiler is wrong, rather I think it is pointing out a possibly latent bug in llvm.
1) There is no sequence point for the `>=` operation.
2) A call to a `DenseMapBase::operator[]` can have the side effect of the map reallocating a larger store (more Buckets, via a call to `DenseMap::grow`).
3) It seems perfectly legal for a host compiler to generate assembly that stores the result of a call to `operator[]` on the stack (that's what my host compile of GVN.cpp is doing) . A second call to `operator[]` //might// encourage the map to 'grow' thus making any pointers to the map's store invalid. The `>=` compares the first and second values. If the first happens to be a pointer produced from operator[], it could be invalid when dereferenced at the time of comparison.
The assembly generated from the Window's host compiler does show the result of the first access to the map via `operator[]` produces a pointer to an unsigned int. And that pointer is being stored on the stack. If a second call to the map (which does occur) causes the map to grow, that address (on the stack) is now invalid.
Alina Sbirlea [Thu, 10 Jan 2019 19:29:04 +0000 (19:29 +0000)]
Use MemorySSA in LICM to do sinking and hoisting.
Summary:
Step 2 in using MemorySSA in LICM:
Use MemorySSA in LICM to do sinking and hoisting, all under "EnableMSSALoopDependency" flag.
Promotion is disabled.
Enable flag in LICM sink/hoist tests to test correctness of this change. Moved one test which
relied on promotion, in order to test all sinking tests.
Craig Topper [Thu, 10 Jan 2019 19:02:14 +0000 (19:02 +0000)]
[X86] Simplify the BRCOND handling for FCMP_UNE.
Despite what the comment says, FCMP_UNE would be an OR not an AND. In the lowering code the first branch created still goes to the original destination. The second branch was exchanged to go to where the subsequent unconditional branch went. This is different than what we do for FCMP_OEQ where both branches that we create go to the original unconditional branch.
As far as I can tell, I think this means we don't need to exchange the branch target with the unconditional branch for FCMP_UNE at all.
when `FILECHECK_DUMP_INPUT_ON_FAILURE` is set in the environment.
By default llvm-lit propagates `FILECHECK_DUMP_INPUT_ON_FAILURE` and
`FILECHECK_OPTS` from llvm-lit's environment into the test environment.
Unfortunately this can break FileCheck's tests because they expect that
these environment variables not to be set.
Neil Henning [Thu, 10 Jan 2019 16:21:08 +0000 (16:21 +0000)]
[AMDGPU] Fix dwordx3/southern-islands failures.
This commit fixes the dwordx3/southern-islands failures that were found
in bugzilla https://bugs.llvm.org/show_bug.cgi?id=40129, by not
generating the dwordx3 variants of load/store instructions that were
added to the ISA after southern islands.
James Y Knight [Thu, 10 Jan 2019 16:07:20 +0000 (16:07 +0000)]
[opaque pointer types] Remove some calls to generic Type subtype accessors.
That is, remove many of the calls to Type::getNumContainedTypes(),
Type::subtypes(), and Type::getContainedType(N).
I'm not intending to remove these accessors -- they are
useful/necessary in some cases. However, removing the pointee type
from pointers would potentially break some uses, and reducing the
number of calls makes it easier to audit.
Sanjay Patel [Thu, 10 Jan 2019 15:27:23 +0000 (15:27 +0000)]
[x86] fix remaining miscompile bug in horizontal binop matching (PR40243)
When we use the partial-matching function on a 128-bit chunk, we must
account for the possibility that we've matched undef halves of the
original source vectors, so the outputs may need to be reset.
This should allow closing PR40243:
https://bugs.llvm.org/show_bug.cgi?id=40243
Sanjay Patel [Thu, 10 Jan 2019 15:04:52 +0000 (15:04 +0000)]
[x86] fix horizontal binop matching for 256-bit vectors (PR40243)
This is a partial fix for:
https://bugs.llvm.org/show_bug.cgi?id=40243
...as seen in the integer test, we still need to correct the result when using the
existing (old) horizontal op matching function because it does not model the way
x86 256-bit horizontal ops return results (each 128-bit half is its own horizontal-op).
A potential follow-up change for that is discussed in the bug report - see also D56490.
This generally duplicates a lot of the existing matching code, but we can't just remove
that without introducing regressions, so the existing code is renamed and used less often.
Follow-ups may try to reduce that overlap.
Bryan Chan [Thu, 10 Jan 2019 15:02:37 +0000 (15:02 +0000)]
[AArch64] Fix operation actions for FP16 vector intrinsics
Summary:
This patch changes the legalization action for some half-precision floating-
point vector intrinsics (FSIN, FLOG, etc.) from Promote to Expand. These ops
are not supported in hardware for half-precision vectors, but promotion is
not always possible (for v8f16 operands). Changing the action to Expand fixes
an assertion failure in the legalizer when the frontend produces such ops.
In addition, a quick microbenchmark shows that, in the v4f16 case,
expanding introduces fewer spills and is therefore slightly faster than
promoting.
James Henderson [Thu, 10 Jan 2019 14:10:02 +0000 (14:10 +0000)]
[llvm-symbolizer] Add support for specifying addresses on command-line
See https://bugs.llvm.org/show_bug.cgi?id=40070.
GNU addr2line accepts input addresses both on the command-line and via
stdin. llvm-symbolizer previously only supported the latter. This
change adds support for the former. As with addr2line, the new
behaviour is to only look for addresses on stdin if no positional
arguments were provided to llvm-symbolizer.
Andrea Di Biagio [Thu, 10 Jan 2019 13:59:13 +0000 (13:59 +0000)]
[MCA] Fix wrong definition of ResourceUnitMask in DefaultResourceStrategy.
Field ResourceUnitMask was incorrectly defined as a 'const unsigned' mask. It
should have been a 64 bit quantity instead. That means, ResourceUnitMask was
always implicitly truncated to a 32 bit quantity.
This issue has been found by inspection. Surprisingly, that bug was latent, and
it never negatively affected any existing upstream targets.
This patch fixes the wrong definition of ResourceUnitMask, and adds a bunch of
extra debug prints to help debugging potential issues related to invalid
processor resource masks.
Fedor Sergeev [Thu, 10 Jan 2019 10:01:53 +0000 (10:01 +0000)]
[LoopUnroll] add parsing for unroll parameters in -passes pipeline
Allow to specify loop-unrolling with optional parameters explicitly
spelled out in -passes pipeline specification.
Introducing somewhat generic way of specifying parameters parsing via
FUNCTION_PASS_PARAMETRIZED pass registration.
Syntax of parametrized unroll pass name is as follows:
'unroll<' parameter-list '>'
Where parameter-list is ';'-separate list of parameter names and optlevel
optlevel: 'O[0-3]'
parameter: { 'partial' | 'peeling' | 'runtime' | 'upperbound' }
negated: 'no-' parameter
Sam Parker [Thu, 10 Jan 2019 08:36:33 +0000 (08:36 +0000)]
[ARM] Size reduce teq to eors
Add t2TEQrr to the map of instructions with can be reduced down into
a T1 instruction. This is a special case because TEQ just sets the
CPSR and doesn't write to a GPR, which is not the case for EOR. So,
we need to ensure that the EOR can write to the first operand.
Craig Topper [Thu, 10 Jan 2019 07:43:54 +0000 (07:43 +0000)]
[X86] Disable DomainReassignment pass when AVX512BW is disabled to avoid injecting VK32/VK64 references into the MachineIR
Summary:
This pass replaces GR8/GR16/GR32/GR64 with their equivalent sized mask register classes. But VK32/VK64 aren't legal without AVX512BW. Apparently this mostly appears to work if the register coalescer is able to remove the VK32/VK64 register class reference. Or if we don't ever spill it. But there's no guarantee of that.
Another Intel employee managed to trigger a crash due to this with ISPC. Unfortunately, I've lost the test case he sent me at the time. I'm trying to get him to reproduce it for me. I'd like to get this in before 8.0 branches since its a little scary.
The regressions here are unfortunate, but I think we can make some improvements to DAG combine, load folding, etc. to fix them. Just not sure if we can get that done for 8.0.
[AArch64] Emit the correct MCExpr relocations specifiers like VK_ABS_G0, etc
Summary:
D55896 and D56029 add support to emit fixups for :abs_g0: , :abs_g1_s: , etc.
This patch adds the necessary enums and MCExpr needed for lowering these.
This is a second attempt at r350778, which was reverted in
r350789. The only change is that the unimplemented-simd128 feature has
been renamed simd128-unimplemented, since naming it
unimplemented-simd128 somehow made the simd128 feature flag enable the
unimplemented-simd128 feature on Windows.
Alina Sbirlea [Thu, 10 Jan 2019 00:16:54 +0000 (00:16 +0000)]
[MemorySSA] Remove optimized value when reseting optimized.
Summary:
If we don't reset the optimized value O for access A, even though A is no longer optimized to O, A will still show up in that O's users list.
This fails verification when hoisting a Def outside a loop, even though the updates are correct.
The reason is that the phi in the loop header still find as user the hoisted def, because the Def has a pointer to the Phi in its optimized operand.
Craig Topper [Thu, 10 Jan 2019 00:14:27 +0000 (00:14 +0000)]
[X86] After turning VSELECT into SHRUNKBLEND, make we push the VSELECT into the worklist so it can be deleted.
Found while trying to figure out why my second version of D56421 worked better than the first version. We weren't deleting the vselect in a timely fashion and that caused SimplfyDemandedBit to see an additional user.
The new version doesn't have this problem so this fix isn't needed there, but seemed like the right thing to do.
Summary:
This replaces the old ad-hoc -wasm-enable-unimplemented-simd
flag. Also makes the new unimplemented-simd128 feature imply the
simd128 feature.
Eli Friedman [Wed, 9 Jan 2019 23:39:26 +0000 (23:39 +0000)]
[SimplifyLibCalls] Fix memchr expansion for constant strings.
The C standard says "The memchr function locates the first
occurrence of c (converted to an unsigned char)[...]". The expansion
was missing the conversion to unsigned char.
David Major [Wed, 9 Jan 2019 23:36:32 +0000 (23:36 +0000)]
Don't require a null terminator when loading objects
When a null terminator is required and the file size is a multiple of the system page size, MemoryBuffer will prefer pread() over mmap(), which can result in excessive memory usage.
Heejin Ahn [Wed, 9 Jan 2019 23:05:21 +0000 (23:05 +0000)]
[WebAssembly] Print a debug message at the start of each pass
Summary:
Looks like many passes print its pass description as a debug message at
the start of each pass, so added that to (mostly newly added) other
passes as well.
Summary:
Instead of using two separate callbacks to return the entry count and the
relative block frequency, use a single callback to return callsite
count. This would allow better supporting hybrid mode in the future as
the count of callsite need not always be derived from entry count (as in
sample PGO).
[CodeGen] Ignore return sext/zext attributes of unused results for tail calls
If the caller's return type does not have a zeroext attribute but the
callee does a tail call zeroext, we won't consider the tail call during
CodeGenPrepare because the attributes don't match.
However, if the result of the tail call has no uses, it makes sense to
drop the sext/zext attributes.
Thomas Lively [Wed, 9 Jan 2019 18:13:11 +0000 (18:13 +0000)]
[WebAssembly] Standardize order of SIMD bitselect arguments
Summary:
For some reason the backend assumed that the condition mask would be
the first argument to the LLVM intrinsic, but everywhere else the
condition mask is the third argument.
Hubert Tong [Wed, 9 Jan 2019 16:00:39 +0000 (16:00 +0000)]
[unittests][Support] AIX: Skip sticky bit file tests
On AIX, attempting (without root) to set the sticky bit on a file with
the `chmod` utility will give:
```
chmod: not all requested changes were made to <file>
```
The same occurs when modifying other permission bits on a file with the
sticky bit already set.
It seems that the `chmod` function will report success despite failing
to set the sticky bit.
Alexey Bataev [Wed, 9 Jan 2019 15:41:44 +0000 (15:41 +0000)]
[DEBUGINFO][NVPTX]Make tests more strict, NFC.
NVPTX format requires that no labels/label arithmetics is used in the
debug info sections. To avoid possible problems with the adding/modifying the debug info functionality, made these tests more strict.
Kristof Beyls [Wed, 9 Jan 2019 15:13:34 +0000 (15:13 +0000)]
Initial AArch64 SLH implementation.
This is an initial implementation for Speculative Load Hardening for
AArch64. It builds on top of the recently introduced
AArch64SpeculationHardening pass.
This doesn't implement (yet) some of the optimizations implemented for
the X86SpeculativeLoadHardening pass. I thought introducing the
optimizations incrementally in follow-up patches should make this easier
to review.
llvm-objdump currently does not do that.
Patch changes the behavior to match the GNU objdump.
That is useful for implementing -z/--disassemble-zeroes (D56083),
it allows omitting first zero bytes and keep the information
about the symbol address in the output.
Valery Pykhtin [Wed, 9 Jan 2019 13:43:32 +0000 (13:43 +0000)]
[AMDGPU] Fix DPP combiner
Fixed issue with identity values and other cases, f32/f16 identity values to be added later. fma/mac instructions is disabled for now.
Test is fully reworked, added comments. Other fixes:
1. dpp move with uses and old reg initializer should be in the same BB.
2. bound_ctrl:0 is only considered when bank_mask and row_mask are fully enabled (0xF). Othervise the old register value is checked for identity.
3. Added add, subrev, and, or instructions to the old folding function.
4. Kill flag is cleared for the src0 (DPP register) as it may be copied into more than one user.
Follow up patch of rL350385, for adding predres
command line option. This patch renames the
feature as to keep it aligned with the option
passed by/to clang
As seen, the first entry's beginning and ending addresses evalute to 0,
which meant that the entry inadvertently became an "end of list" entry,
resulting in the location list ending sooner than expected.
To fix this, omit all entries with empty ranges. Location list entries
with empty ranges do not have any effect, as specified by DWARF, so we
might as well drop them:
"A location list entry (but not a base address selection or end of list
entry) whose beginning and ending addresses are equal has no effect
because the size of the range covered by such an entry is zero."
Max Kazantsev [Wed, 9 Jan 2019 07:28:13 +0000 (07:28 +0000)]
[IPT] Drop cache less eagerly in GVN and LoopSafetyInfo
Current strategy of dropping `InstructionPrecedenceTracking` cache is to
invalidate the entire basic block whenever we change its contents. In fact,
`InstructionPrecedenceTracking` has 2 internal strictures: `OrderedInstructions`
that is needed to be invalidated whenever the contents changes, and the map
with first special instructions in block. This second map does not need an
update if we add/remove a non-special instuction because it cannot
affect the contents of this map.
This patch changes API of `InstructionPrecedenceTracking` so that it now
accounts for reasons under which we invalidate blocks. This should lead
to much less recalculations of the map and should save us some compile time
because in practice we don't typically add/remove special instructions.
Craig Topper [Wed, 9 Jan 2019 04:21:12 +0000 (04:21 +0000)]
[X86] Correct the MaskVT for avx512 gather/scatter intrinsics to use the min of the number of index and data elements.
When the result type is v2i64/v2f64 and the index element size is i32, the index vector has two unused elements making the type v4i32. The mask VT should match the number of memory accesses that will be made.
This is consistent with the isel patterns used for the target independent gather/scatter intrinsic.