Craig Topper [Tue, 1 Aug 2017 15:10:25 +0000 (15:10 +0000)]
[InstCombine] Remove explicit check for impossible condition. Replace with assert
Summary:
As far as I can tell the earlier call getLimitedValue will guaranteed ShiftAmt is saturated to BitWidth-1 preventing it from ever being equal or greater than BitWidth.
At one point in the past the getLimitedValue call was only passed BitWidth not BitWidth - 1. This would have allowed the equality case to get here. And in fact this check was initially added as just BitWidth == ShiftAmt, but was changed shortly after to include > which should have never been possible.
Tobias Grosser [Tue, 1 Aug 2017 14:40:55 +0000 (14:40 +0000)]
[PostDom] document the current handling of infinite loops and unreachables
Summary:
As we are in the process of changing the behavior of how the post-dominator tree
is computed, make sure we have some more test coverage in this area.
Current inconsistencies:
- Newly unreachable nodes are not added as new roots, in case the PDT is updated
but not rebuilt.
- Newly unreachable loops are not added to the CFG at all (neither when
building from scratch nor when updating the CFG). This is inconsistent with
the fact that unreachables are added to the PDT, but unreachable loops not.
On the other side, PDT relationships are not loosened at the moment in
cases where new unreachable loops are built.
This commit is providing additional test coverage for
https://reviews.llvm.org/D35851
Nirav Dave [Tue, 1 Aug 2017 13:45:35 +0000 (13:45 +0000)]
[DAG] Extend visitSCALAR_TO_VECTOR optimization to truncated vector.
Summary:
Allow SCALAR_TO_VECTOR of EXTRACT_VECTOR_ELT to reduce to
EXTRACT_SUBVECTOR of vector shuffle when output is smaller. Marginally
improves vector shuffle computations.
This patch enables control flow optimization for
variations of BBIT instruction. In this case
optimization removes unnecessary branch after
BBIT instruction.
Support itineraries in TargetSubtargetInfo::getSchedInfoStr - Now if the given instr does not have sched model then we try to calculate the latecy/throughput with help of itineraries.
Differential Revision https://reviews.llvm.org/D35997
Petr Hosek [Tue, 1 Aug 2017 05:18:30 +0000 (05:18 +0000)]
[llvm][llvm-objcopy] Added support for outputting to binary in llvm-objcopy
This change adds the "-O binary" flag which directs llvm-objcopy to
output the object file to the same format as GNU objcopy does when given
the flag "-O binary". This was done by splitting the Object class into
two subclasses ObjectELF and ObjectBianry which each output a different
format but relay on the same code to read in the Object in Object.
Davide Italiano [Tue, 1 Aug 2017 05:14:45 +0000 (05:14 +0000)]
[MetaRenamer] Leave `@main` alone.
To the best of my knowledge -metarenamer is used in two cases:
1) obfuscate names, when e.g. they contain informations that
can't be shared.
2) Improve clarity of the textual IR for testcases.
One of the usecases if getting the output of `opt` and passing it
to the lli interpreter to run the test. If metarenamer renames
@main, lli can't find an entry point.
Craig Topper [Tue, 1 Aug 2017 04:18:34 +0000 (04:18 +0000)]
[MathExtras] Remove unnecessary cast of a constant 1 in a subtract.
Pretty sure this will automatically promoted to match the type of the other operand of the subtract. There's plenty of other similar code around here without this cast.
Hiroshi Inoue [Tue, 1 Aug 2017 03:32:15 +0000 (03:32 +0000)]
[StackColoring] Update AliasAnalysis information in stack coloring pass
Stack coloring pass need to maintain AliasAnalysis information when merging stack slots of different types.
Actually, there is a FIXME comment in StackColoring.cpp
// FIXME: In order to enable the use of TBAA when using AA in CodeGen,
// we'll also need to update the TBAA nodes in MMOs with values
// derived from the merged allocas.
But, TBAA has been already enabled in CodeGen without fixing this pass.
The incorrect TBAA metadata results in recent failures in bootstrap test on ppc64le (PR33928) by allowing unsafe instruction scheduling.
Although we observed the problem on ppc64le, this is a platform neutral issue.
This patch makes the stack coloring pass maintains AliasAnalysis information when merging multiple stack slots.
Petr Hosek [Tue, 1 Aug 2017 00:33:58 +0000 (00:33 +0000)]
Reland "[LLVM][llvm-objcopy] Added basic plumbing to get things started"
As discussed on llvm-dev I've implemented the first basic steps towards
llvm-objcopy/llvm-objtool (name pending).
This change adds the ability to copy (without modification) 64-bit
little endian ELF executables that have SHT_PROGBITS, SHT_NOBITS,
SHT_NULL and SHT_STRTAB sections.
Eli Friedman [Tue, 1 Aug 2017 00:28:40 +0000 (00:28 +0000)]
[ScheduleDAG] Don't schedule node with physical register interference
https://reviews.llvm.org/D31536 didn't really solve the problem it was
trying to solve; it got rid of the assertion failure, but we were still
scheduling the DAG incorrectly (mixing together instructions from
different calls), leading to a MachineVerifier failure.
In order to schedule the DAG correctly, we have to make sure we don't
schedule a node which should be blocked by an interference. Fix
ScheduleDAGRRList::PickNodeToScheduleBottomUp so it doesn't pick a node
like that.
The added call to FindAvailableNode() is the key change here; this makes
sure we don't try to schedule a call while we're in the middle of
scheduling a different call. I'm not sure this is the right approach; in
particular, I'm not sure how to prove we don't end up with an infinite
loop of repeatedly backtracking.
This also reverts the code change from D31536. It doesn't do anything
useful: we should never schedule an ADJCALLSTACKDOWN unless we've
already scheduled the corresponding ADJCALLSTACKUP.
Alina Sbirlea [Tue, 1 Aug 2017 00:28:29 +0000 (00:28 +0000)]
Allow None as a MemoryLocation to getModRefInfo
Summary:
Adding part of the changes in D30369 (needed to make progress):
Current patch updates AliasAnalysis and MemoryLocation, but does _not_ clean up MemorySSA.
Original summary from D30369, by dberlin:
Currently, we have instructions which affect memory but have no memory
location. If you call, for example, MemoryLocation::get on a fence,
it asserts. This means things specifically have to avoid that. It
also means we end up with a copy of each API, one taking a memory
location, one not.
This starts to fix that.
We add MemoryLocation::getOrNone as a new call, and reimplement the
old asserting version in terms of it.
We make MemoryLocation optional in the (Instruction, MemoryLocation)
version of getModRefInfo, and kill the old one argument version in
favor of passing None (it had one caller). Now both can handle fences
because you can just use MemoryLocation::getOrNone on an instruction
and it will return a correct answer.
We use all this to clean up part of MemorySSA that had to handle this difference.
Note that literally every actual getModRefInfo interface we have could be made private and replaced with:
getModRefInfo(Instruction, Optional<MemoryLocation>)
and
getModRefInfo(Instruction, Optional<MemoryLocation>, Instruction, Optional<MemoryLocation>)
and delegating to the right ones, if we wanted to.
David Blaikie [Mon, 31 Jul 2017 21:48:42 +0000 (21:48 +0000)]
DebugInfo: Put range base specifier entry functionality behind a flag
Chromium's gold build seems to have trouble with this (gold produces
errors) - not sure if it's gold that's not coping with the valid
representation, or a bug in the implementation in LLVM, etc.
[codeview] Ignore DBG_VALUEs when choosing a BB start source loc
When the first instruction of a basic block has no location (consider a
LEA materializing the address of an alloca for a call), we want to start
the line table for the block with the first valid source location in the
block. We need to ignore DBG_VALUE instructions during this scan to get
decent line tables.
Update phi nodes in LowerTypeTests control flow simplification
D33925 added a control flow simplification for -O2 --lto-O0 builds that
manually splits blocks and reassigns conditional branches but does not
correctly update phi nodes. If the else case being branched to had
incoming phi nodes the control-flow simplification would leave phi nodes
in that BB with an unhandled predecessor.
We don't write any actual symbols to this stream yet, but for
now we just create the stream and hook it up to the appropriate
places and give it a valid header.
[X86][InstCombine] Add basic simplification support for BEXTR/BEXTRI intrinsics.
This patch adds simplification support for the BEXTR/BEXTRI intrinsics to match gcc. This only supports cases that fold to 0 or can be fully constant folded. Theoretically we could support converting to AND if the shift part is unused or to only a shift if the mask doesn't modify any bits after an equivalent shl. gcc doesn't do these transformations either.
I put this in InstCombine, but it could be done in InstSimplify. It would be the first target specific intrinsic in InstSimplify.
[lit] Avoid copying llvm/utils/lit/tests/Inputs with lit site configs
Summary:
This is an alternative solution to running the lit test suite on bots
without polluting the source directory. Each input test suite gets an
auto-generated site config in the build directory that points back to
the test input source directory.
This adds some cmake comlexity, but now we don't need to remove and
re-copy the test input directory before every test.
[TargetPassConfig] Feature generic options to setup start/stop-after/before
This patch refactors the code used in llc such that all the users of the
addPassesToEmitFile API have access to a homogeneous way of handling
start/stop-after/before options right out of the box.
In particular, just invoking addPassesToEmitFile will set the proper
pipeline without additional effort (modulo parsing a .mir file if the
start-before/after options are used.
[CGP] use subtract or subtract-of-cmps for result of memcmp expansion
As noted in the code comment, transforming this in the other direction might require
a separate transform here in CGP given the block-at-a-time DAG constraint.
Besides that theoretical motivation, there are 2 practical motivations for the
subtract-of-cmps form:
1. The codegen for both x86 and PPC is better for this IR (though PPC could be better still).
There is discussion about canonicalizing IR to the select form
( http://lists.llvm.org/pipermail/llvm-dev/2017-July/114885.html ),
so we probably need to add DAG transforms for those patterns anyway, but this improves the
memcmp output without waiting for that step.
2. If we allow vector-sized chunks for the load and compare, x86 is better prepared to convert
that to optimal code when using subtract-of-cmps, so another prerequisite patch is avoided
if we choose to enable that.
[DWARF] Added verification check for tags in accelerator tables. This patch verifies that the atom tag is actually the same with the tag of the DIE that we retrieve from the table.
[AVX-512] Remove patterns that select vmovdqu8/16 for unmasked loads. Prefer vmovdqa64/vmovdqu64 instead.
These were taking priority over the aligned load instructions since there is no vmovda8/16. I don't think there is really a difference between aligned and unaligned on newer cpus so I don't think it matters which instructions we use.
But with this change we reduce the size of the isel table a little and we allow the aligned information to pass through to the evex->vec pass and produce the same output has avx/avx2 in some cases.
I also generally dislike patterns rooted in a bitcast which these were.
Benjamin Kramer [Mon, 31 Jul 2017 15:32:39 +0000 (15:32 +0000)]
[DebugInfo] Don't overwrite DWARFUnit fields if the CU DIE doesn't have them.
DIEs are lazily deserialized so it's possible that the DWO CU is created
before the DIE is parsed. DWO shares .debug_addr and .debug_ranges with the
object file so overwriting the offset with 0 will make the CU unusable.
No test case because I couldn't get clang to emit a non-zero range base.
Don Hinton [Mon, 31 Jul 2017 15:18:57 +0000 (15:18 +0000)]
[docker] Fix unmatched quote problem in here-document on older versions of bash
Summary:
When outputing usage, emit here-document directly instead of
saving in a variable first -- avoids problem with bash 3.2.57 where an
unmatched ' in the here-document results in the following error:
./build_docker_image.sh: line 135: unexpected EOF while looking for matching `''
bash --version
GNU bash, version 3.2.57(1)-release (x86_64-apple-darwin16)
[SLP] Initial rework for min/max horizontal reduction vectorization, NFC.
Summary: All getReductionCost() functions are renamed to getArithmeticReductionCost() + added basic infrastructure to handle non-binary reduction operations.
The Loop Vectorizer generates redundant operations when manipulating masks:
AND with true, OR with false, compare equal to true. Instead of relying on
a subsequent pass to clean them up, this patch avoids generating them.
Use null (no-mask) to represent all-one full masks, instead of a constant
all-one vector, following the convention of masked gathers and scatters.
Preparing for a follow-up VPlan patch in which these mask manipulating
operations are modeled using recipes.
Martin Storsjo [Mon, 31 Jul 2017 11:18:41 +0000 (11:18 +0000)]
[llvm-dlltool] Write correct weak externals
Previously, the created object files for the import library were broken.
Write the symbol table before the string table. Simplify the code by
using a separate variable Prefix instead of duplicating a few lines.
Also update the coff-weak-exports to actually check that the generated
weak symbols can be found as intended.
Guard print() functions only used by dump() functions.
Summary:
Since r293359, most dump() function are only defined when
`!defined(NDEBUG) || defined(LLVM_ENABLE_DUMP)` holds. print() functions
only used by dump() functions are now unused in release builds,
generating lots of warnings. This patch only defines some print()
functions if they are used.
[LoopInterchange] Do not interchange loops with function calls.
Summary:
Without any information about the called function, we cannot be sure
that it is safe to interchange loops which contain function calls. For
example there could be dependences that prevent interchanging between
accesses in the called function and the loops. Even functions without any
parameters could cause problems, as they could access memory using
global pointers.
For now, I think it is only safe to interchange loops with calls marked
as readnone.
With this patch, the LLVM test suite passes with `-O3 -mllvm
-enable-loopinterchange` and LoopInterchangeProfitability::isProfitable
returning true for all loops. check-llvm and check-clang also pass when
bootstrapped in a similar fashion, although only 3 loops got
interchanged.
David Blaikie [Sun, 30 Jul 2017 22:10:00 +0000 (22:10 +0000)]
DebugInfo: Use base address selection entries in debug_ranges to reduce relocations
(from comments in the test)
Group ranges in a range list that apply to the same section and use a base
address selection entry to reduce the number of relocations to one reloc per
section per range list. DWARF5 debug_rnglist will be more efficient than this
in terms of relocations, but it's still better than one reloc per entry in a
range list.
This is an object/executable size tradeoff - shrinking objects, but growing
the linked executable. In one large binary tested, total object size (not just
debug info) shrank by 16%, entirely relocation entries. Linked executable
grew by 4%. This was with compressed debug info in the objects, uncompressed
in the linked executable. Without compression in the objects, the win would be
smaller (the growth of debug_ranges itself would be more significant).
Use `llvm-objdump -dwarf=frames` to dump the .eh_frame to validate the
output textually rather than compare the binary output. This makes it
easier to see what is being checked. NFC.
David Blaikie [Sun, 30 Jul 2017 08:12:07 +0000 (08:12 +0000)]
DebugInfo: Use DWP cu_index to speed up symbolizing (as intended)
I was a bit lazy when I first implemented this & skipped the index
lookup - obviously for large files this becomes pretty crucial, so here
we go, do the index lookup. Speeds up large DWP symbolizing by... lots.
(20m -> 20s, actually, maybe more in a release build (that was a release
build without index lookup, compared to a debug/non-release build with
the index usage))
David Blaikie [Sun, 30 Jul 2017 01:34:08 +0000 (01:34 +0000)]
DebugInfo: Provide option for explicitly specifying the name of the DWP file
If you've archived the DWP file somewhere it's probably useful to be
able to just tell llvm-symbolizer where it is when you're symbolizing
stack traces from the binary.
This only provides a mechanism for specifying a single DWP file, good if
you're symbolizing a program with a single DWP file, but it's likely if
the program is dynamically linked that you might have a DWP for each
dynamic library - in which case this feature won't help (at least as
it's surfaced in llvm-symbolizer for now) - in theory it could be
extended to specify a collection of DWP files that could all be
consulted for split CU hash resolution.
[AArch64] Tie source and destination operands for AESMC/AESIMC.
Summary:
Most CPUs implementing AES fusion require instruction pairs of the form
AESE Vn, _
AESMC Vn, Vn
and
AESD Vn, _
AESIMC Vn, Vn
The constraint is added to AES(I)MC instructions which use the result of
an AES(E|D) instruction by using AES(I)MCTrr pseudo instructions, which
constraint source and destination registers to be the same.
A nice side effect of this change is that now all possible pairs are
scheduled back-to-back on the exynos-m1 for the misched-fusion-aes.ll
test case.
I had to update aes_load_store. The version I added initially was very
reduced and with the new constraint, AESE/AESMC could not be scheduled
back-to-back. I updated the test to be more realistic and still expose
the same scheduling problem as the initial test case.