The bug showed up as a compile-time assertion failure:
Assertion `NumBits >= MIN_INT_BITS && "bitwidth too small"' failed
when building msan tests on x86-64.
Prior to r236850, this bug was masked due to a bogus alignment check,
which also accidentally rejected non-byte-sized accesses. Afterwards,
an invalid ElementSizeBytes == 0 got further into the function, and
triggered the assertion failure.
It would probably be a good idea to allow it to handle merging stores
of unusual widths as well, but for now, to un-break it, I'm just
making the minimal fix.
Differential Revision: http://reviews.llvm.org/D9626
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@236927 91177308-0d34-0410-b5e6-96231b3b80d8
When emitting something like 'add x, 1000' if we remat the 1000 then we should be able to
mark the vreg containing 1000 as killed. Given that we go bottom up in fast-isel, a later
use of 1000 will be higher up in the BB and won't kill it, or be impacted by the lower kill.
However, rematerialised constant expressions aren't generated bottom up. The local value save area
grows downwards. This means that if you remat 2 constant expressions which both use 1000 then the
first will kill it, then the second, which is *lower* in the BB will read a killed register.
This is the case in the attached test where the 2 GEPs both need to generate 'add x, 6680' for the constant offset.
Note that this commit only makes kill flag generation conservative. There's nothing else obviously wrong with
the local value save area growing downwards, and in fact it needs to for handling arbitrarily complex constant expressions.
However, it would be nice if there was a solution which would let us generate more accurate kill flags, or just kill flags completely.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@236922 91177308-0d34-0410-b5e6-96231b3b80d8
The code that builds the dependence graph assumes that two PseudoSourceValues
don't alias. In a tail calling function two FixedStackObjects might refer to the
same location. Worse 'immutable' fixed stack objects like function arguments are
not immutable and will be clobbered.
Change this so that a load from a FixedStackObject is not invariant in a tail
calling function and don't return a PseudoSourceValue for an instruction in tail
calling functions when building the dependence graph so that we handle function
arguments conservatively.
Fix for PR23459.
rdar://20740035
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@236916 91177308-0d34-0410-b5e6-96231b3b80d8
This new class in a global context contain arch-specific knowledge in order
to provide LLVM libraries, tools and projects with the ability to understand
the architectures. For now, only FPU, ARCH and ARCH extensions on ARM are
supported.
Current behaviour it to parse from free-text to enum values and back, so that
all users can share the same parser and codes. This simplifies a lot both the
ASM/Obj streamers in the back-end (where this came from), and the front-end
parsers for command line arguments (where this is going to be used next).
The previous implementation, using .def/.h includes is deprecated due to its
inflexibility to be built without the backend support and for being too
cumbersome. As more architectures join this scheme, and as more features of
such architectures are added (such as hardware features, type sizes, etc) into
a full blown TargetDescription class, having a set of classes is the most
sane implementation.
The ultimate goal of this refactor both LLVM's and Clang's target description
classes into one unique interface, so that we can de-duplicate and standardise
the descriptions, as well as make it available for other front-ends, tools,
etc.
The FPU parsing for command line options in Clang has been converted to use
this new library and a number of aliases were added for compatibility:
* A bogus neon-vfpv3 alias (neon defaults to vfp3)
* armv5/v6
* {fp4/fp5}-{sp/dp}-d16
Next steps:
* Port Clang's ARCH/EXT parsing to use this library.
* Create a TableGen back-end to generate this information.
* Run this TableGen process regardless of which back-ends are built.
* Expose more information and rename it to TargetDescription.
* Continue re-factoring Clang to use as much of it as possible.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@236900 91177308-0d34-0410-b5e6-96231b3b80d8
When selecting an extract instruction, we don't actually generate code but instead work out which register we are reading, and rewrite uses of the extract def to the source register. This is done via updateValueMap,.
However, its possible that the source register we are rewriting *to* to also have uses. If those uses are after a kill of the value we are rewriting *from* then we have uses after a kill and the verifier fails.
This code checks for the case where the to register is also used, and if so it clears all kill on the from register. This is conservative, but better that always clearing kills on the from register.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@236897 91177308-0d34-0410-b5e6-96231b3b80d8
Summary:
There are several unhandled edge cases in BasicAA's GetLinearExpression
method. This changes fixes outstanding issues, including zext / sext of
a constant with the sign bit set, and the refusal to decompose zexts or
sexts of wrapping arithmetic.
Test Plan: Unit tests added in //q.ext.ll//.
Patch by Nick White.
Reviewers: hfinkel, sanjoy
Reviewed By: hfinkel, sanjoy
Subscribers: sanjoy, llvm-commits, hfinkel
Differential Revision: http://reviews.llvm.org/D6682
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@236894 91177308-0d34-0410-b5e6-96231b3b80d8
A trunc from i32 to i1 on x86_64 generates an instruction such as
%vreg19<def> = COPY %vreg9:sub_8bit<kill>; GR8:%vreg19 GR32:%vreg9
However, the copy here should only have the kill flag on the 32-bit path, not the 64-bit one.
Otherwise, we are killing the source of the truncate which could be used later in the program.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@236890 91177308-0d34-0410-b5e6-96231b3b80d8
This changes the shape of the statepoint intrinsic from:
@llvm.experimental.gc.statepoint(anyptr target, i32 # call args, i32 unused, ...call args, i32 # deopt args, ...deopt args, ...gc args)
to:
@llvm.experimental.gc.statepoint(anyptr target, i32 # call args, i32 flags, ...call args, i32 # transition args, ...transition args, i32 # deopt args, ...deopt args, ...gc args)
This extension offers the backend the opportunity to insert (somewhat) arbitrary code to manage the transition from GC-aware code to code that is not GC-aware and back.
In order to support the injection of transition code, this extension wraps the STATEPOINT ISD node generated by the usual lowering lowering with two additional nodes: GC_TRANSITION_START and GC_TRANSITION_END. The transition arguments that were passed passed to the intrinsic (if any) are lowered and provided as operands to these nodes and may be used by the backend during code generation.
Eventually, the lowering of the GC_TRANSITION_{START,END} nodes should be informed by the GC strategy in use for the function containing the intrinsic call; for now, these nodes are instead replaced with no-ops.
Differential Revision: http://reviews.llvm.org/D9501
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@236888 91177308-0d34-0410-b5e6-96231b3b80d8
Summary:
I noticed this bug when deubging a WIP on LSR. I wonder whether and how we
should add a regression test for this.
Test Plan: no tests failed.
Reviewers: atrick
Subscribers: hfinkel, llvm-commits
Differential Revision: http://reviews.llvm.org/D9536
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@236887 91177308-0d34-0410-b5e6-96231b3b80d8
The test here was sinking the AND here to a lower BB:
%vreg7<def> = ANDWri %vreg8, 0; GPR32common:%vreg7,%vreg8
TBNZW %vreg8<kill>, 0, <BB#1>; GPR32common:%vreg8
which meant that vreg8 was read after it was killed.
This commit changes the code from clearing kill flags on the AND to clearing flags on all registers used by the AND.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@236886 91177308-0d34-0410-b5e6-96231b3b80d8
Improved the AnalyzeBranch, InsertBranch, and RemoveBranch
functions in order to handle more of our branch instructions.
This requires changes to analyzeCompare and PredicateInstructions.
Specifically, we've added support for new value compare jumps,
improved handling of endloop, added more compare instructions,
and improved support for predicate instructions.
Differential Revision: http://reviews.llvm.org/D9559
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@236876 91177308-0d34-0410-b5e6-96231b3b80d8
The function 'getTargetShuffleMask' already knows how to deal with PSHUFB nodes
where the mask node is a load from constant pool, and the constant pool node
is wrapped by a X86ISD::Wrapper node. This patch extends that logic by teaching
it how to also look through X86ISD::WrapperRIP.
This helps function combineX86ShufflesRecusively to combine more shuffle
sequences containing PSHUFB nodes if we are in RIPRel PIC mode.
Before this change, llc (with -relocation-model=pic -march=x86-64) was unable
to decode a pshufb where the mask was loaded from a constant pool. For example,
the no-op shuffle from test 'x86-fold-pshufb.ll' was not folded into its
operand, so instead of generating a single 'movaps' the backend always
generated a sub-optimal 'movdqa + pshufb' sequence.
Added test x86-fold-pshufb.ll.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@236863 91177308-0d34-0410-b5e6-96231b3b80d8
1) check whether the alignment of the memory is sufficient for the
*merged* store or load to be efficient.
Not doing so can result in some ridiculously poor code generation, if
merging creates a vector operation which must be aligned but isn't.
2) DON'T check that the alignment of each load/store is equal. If
you're merging 2 4-byte stores, the first *might* have 8-byte
alignment, but the second certainly will have 4-byte alignment. We do
want to allow those to be merged.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@236850 91177308-0d34-0410-b5e6-96231b3b80d8
Restructure Triple::getARMCPUForArch so that invalid values will
return nullptr, while retaining the behaviour that an argument
specifying no particular architecture version will give a default
CPU. This will be used by clang to give an error on invalid -march
values.
Also restructure the extraction of the architecture version from
the MArch string a little to hopefully make what it's doing clearer.
Differential Revision: http://reviews.llvm.org/D9599
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@236845 91177308-0d34-0410-b5e6-96231b3b80d8
Summary:
In microMIPS, labels need to know whether they are on code or data. This is
indicated with STO_MIPS_MICROMIPS and can be inferred by being followed
by instructions. For empty basic blocks, we can ensure this by emitting the
.insn directive after the label.
Also, this fixes some failures in our out-of-tree microMIPS buildbots, for the
exception handling regression tests under: SingleSource/Regression/C++/EH
Reviewers: dsanders
Subscribers: llvm-commits
Differential Revision: http://reviews.llvm.org/D9530
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@236815 91177308-0d34-0410-b5e6-96231b3b80d8
Now caller of ELFState::writeSectionContent() methods is responsible to check
a section type and selects an appropriate writeSectionContent method.
So unexpected section type inside writeSectionContent method indicates
a wrong usage of the method and should be guarded by assert.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@236808 91177308-0d34-0410-b5e6-96231b3b80d8
