part of simplifying its interface and usage in preparation for porting
to work with the new pass manager.
Note that this will likely expose that we have dead arguments, members,
and maybe even pass requirements for AA. I'll be cleaning those up in
seperate patches. This just zaps the actual update API.
Differential Revision: http://reviews.llvm.org/D11325
llvm-svn: 242881
change because the diff is *useless*. I assure you, I just switched to
early-return in this function.
Cleanup in preparation for my next commit, as requested in code review!
llvm-svn: 242880
GlobalsModRef) with CallbackVHs that trigger the same behavior.
This is technically more expensive, but in benchmarking some LTO runs,
it seems unlikely to even be above the noise floor. The only way I was
able to measure the performance of GMR at all was to run nothing else
but this one analysis on a linked clang bitcode file. The call graph
analysis still took 5x more time than GMR, and this change at most made
GMR 2% slower (this is well within the noise, so its hard for me to be
sure that this is an actual change). However, in a real LTO run over the
same bitcode, the GMR run takes so little time that the pass timers
don't measure it.
With this, I can remove the last update API from the AliasAnalysis
interface, but I'll actually remove the interface hook point in
a follow-up commit.
Differential Revision: http://reviews.llvm.org/D11324
llvm-svn: 242878
Summary: The current code in LoopUnswtich::processCurrentLoop() mixes trivial loop unswitch and non-trivial loop unswitch together. It goes over all basic blocks in the loop and checks if a condition is trivial or non-trivial unswitch condition. However, trivial unswitch condition can only occur in the loop header basic block (where it controls whether or not the loop does something at all). This refactoring separate trivial loop unswitch and non-trivial loop unswitch. Before going over all basic blocks in the loop, it checks if the loop header contains a trivial unswitch condition. If so, unswitch it. Otherwise, go over all blocks like before but don't check trivial condition any more since they are not possible to be in the other blocks. This code has no functionality change.
Reviewers: meheff, reames, broune
Subscribers: llvm-commits
Differential Revision: http://reviews.llvm.org/D11276
llvm-svn: 242873
Summary:
MCRegAliasIterator only works for physical registers. So, do not run it
on virtual registers.
With this issue fixed, we can resurrect the BranchFolding pass in NVPTX
backend.
Reviewers: jholewinski, bkramer
Subscribers: henryhu, meheff, llvm-commits, jholewinski
Differential Revision: http://reviews.llvm.org/D11174
llvm-svn: 242871
types and loads, loads or stores widened past the size of an alloca,
etc.
This started off with a bug report about big-endian behavior with
bitfields and loads and stores to a { i32, i24 } struct. An initial
attempt to fix this was sent for review in D10357, but that didn't
really get to the root of the problem.
The core issue was that canConvertValue and convertValue in SROA were
handling different bitwidth integers by doing a zext of the integer. It
wouldn't do a trunc though, only a zext! This would in turn lead SROA to
form an i24 load from an i24 alloca, zext it to i32, and then use it.
This would at least produce the wrong value for big-endian systems.
One of my many false starts here was to correct the computation for
big-endian systems by shifting. But this doesn't actually work because
the original code has a 64-bit store to the entire 8 bytes, and a 32-bit
load of the last 4 bytes, and because the alloc size is 8 bytes, we
can't lose that last (least significant if bigendian) byte! The real
problem here is that we're forming an i24 load in SROA which is actually
not sufficiently wide to load all of the necessary bits here. The source
has an i32 load, and SROA needs to form that as well.
The straightforward way to do this is to disable the zext logic in
canConvertValue and convertValue, forcing us to actually load all
32-bits. This seems like a really good change, but it in turn breaks
several other parts of SROA.
First in the chain of knock-on failures, we had places where we were
doing integer-widening promotion even though some of the integer loads
or stores extended *past the end* of the alloca's memory! There was even
a comment about preventing this, but it only prevented the case where
the type had a different bit size from its store size. So I added checks
to handle the cases where we actually have a widened load or store and
to avoid trying to special integer widening promotion in those cases.
Second, we actually rely on the ability to promote in the face of loads
past the end of an alloca! This is important so that we can (for
example) speculate loads around PHI nodes to do more promotion. The bits
loaded are garbage, but as long as they aren't used and the alignment is
suitable high (which it wasn't in the test case!) this is "fine". And we
can't stop promoting here, lots of things stop working well if we do. So
we need to add specific logic to handle the extension (and truncation)
case, but *only* where that extension or truncation are over bytes that
*are outside the alloca's allocated storage* and thus totally bogus to
load or store.
And of course, once we add back this correct handling of extension or
truncation, we need to correctly handle bigendian systems to avoid
re-introducing the exact bug that started us off on this chain of misery
in the first place, but this time even more subtle as it only happens
along speculated loads atop a PHI node.
I've ported an existing test for PHI speculation to the big-endian test
file and checked that we get that part correct, and I've added several
more interesting big-endian test cases that should help check that we're
getting this correct.
Fun times.
llvm-svn: 242869
This optimization allows the DWARF linker to reuse definition of
types it has emitted in previous CUs rather than reemitting them
in each CU that references them. The size and link time gains are
huge. For example when linking the DWARF for a debug build of
clang, this generates a ~150M dwarf file instead of a ~700M one
(the numbers date back a bit and must not be totally accurate
these days).
As with all the other parts of the llvm-dsymutil codebase, the
goal is to keep bit-for-bit compatibility with dsymutil-classic.
The code is littered with a lot of FIXMEs that should be
addressed once we can get rid of the compatibilty goal.
llvm-svn: 242847
This commit begins serialization of the CFI index machine operands by
serializing one kind of CFI instruction - the .cfi_def_cfa_offset instruction.
Reviewers: Duncan P. N. Exon Smith
llvm-svn: 242845
Summary:
In the benchmark (https://github.com/vetter/shoc) we are researching,
the duplicated load is not eliminated because MemoryDependenceAnalysis
hit the BlockScanLimit. This patch change it into a command line option
instead of a hardcoded value.
Patched by Xuetian Weng.
Test Plan: test/Analysis/MemoryDependenceAnalysis/memdep-block-scan-limit.ll
Reviewers: jingyue, reames
Subscribers: reames, llvm-commits
Differential Revision: http://reviews.llvm.org/D11366
llvm-svn: 242842
This makes one substantive change and a few stylistic changes to the
VSX swap optimization pass.
The substantive change is to permit LXSDX and LXSSPX instructions to
participate in swap optimization computations. The previous change to
insert a swap following a SUBREG_TO_REG widening operation makes this
almost trivial.
I experimented with also permitting STXSDX and STXSSPX instructions.
This can be done using similar techniques: we could insert a swap
prior to a narrowing COPY operation, and then permit these stores to
participate. I prototyped this, but discovered that the pattern of a
narrowing COPY followed by an STXSDX does not occur in any of our
test-suite code. So instead, I added commentary indicating that this
could be done.
Other TLC:
- I changed SH_COPYSCALAR to SH_COPYWIDEN to more clearly indicate
the direction of the copy.
- I factored the insertion of swap instructions into a separate
function.
Finally, I added a new test case to check that the scalar-to-vector
loads are working properly with swap optimization.
llvm-svn: 242838
This commit refactors the function 'maybeLexGlobalValue' so that now it reuses
the function 'lexName' when lexing a named global value token.
llvm-svn: 242837
Not every program needs this information.
In particular, it is necessary and sufficient for a static linker to scan the
section table.
llvm-svn: 242833
We insert a bitcast which obfuscates the getCalledFunction for the utility
function which looks up attributes from the called function. Loosing ABI
changing parameter attributes is a bad thing.
rdar://21516488
llvm-svn: 242807
A bit more code cleanup: delete some a trivial true assertion and supporting code, remove a redundant cast, and use count in assertions where feasible.
llvm-svn: 242805
This commit extracts the code that prints out a name of an LLVM value without a
prefix from a function 'PrintLLVMName' into a publicly accessible function named
'printLLVMNameWithoutPrefix'.
This change would be useful for MIR serialization, as it would allow the MIR
printer to reuse this function to print out the names of the external symbol
machine operands.
Reviewers: Duncan P. N. Exon Smith
llvm-svn: 242803
One part of my refactoring from r242705 is untenable due to how CMake caches variables. There is no way other than caching to allow variables to be set in one directory and globally readable, but we really don't want to cache the temporary value marking that a directory has already been included.
llvm-svn: 242793
A patch by Chakshu Grover!
This patch allows constfolding of trunc,rint,nearbyint,ceil and floor intrinsics using APFloat class.
Differential Revision: http://reviews.llvm.org/D11144
llvm-svn: 242763
whether register r9 should be reserved.
This recommits r242737, which broke bots because the number of subtarget
features went over the limit of 64.
This change is needed because we cannot use a backend option to set
cl::opt "arm-reserve-r9" when doing LTO.
Out-of-tree projects currently using cl::opt option "-arm-reserve-r9" to
reserve r9 should make changes to add subtarget feature "reserve-r9" to
the IR.
rdar://problem/21529937
Differential Revision: http://reviews.llvm.org/D11320
llvm-svn: 242756
We can use builders to simplify part of the code and we only check for the existance of the metadata value; this enables us to delete some redundant code.
llvm-svn: 242751
Summary:
When calling llgo-go from the llvm_add_go_executable
cmake function, specify $GO_EXECUTABLE as the go
command to call. Without this, llgo-go searches $PATH
which may be inconsistent with $GO_EXECUTABLE.
Reviewers: pcc
Subscribers: llvm-commits
Differential Revision: http://reviews.llvm.org/D11290
llvm-svn: 242749
Re-apply of r241928 which had to be reverted because of the r241926
revert.
This commit factors out common code from MergeBaseUpdateLoadStore() and
MergeBaseUpdateLSMultiple() and introduces a new function
MergeBaseUpdateLSDouble() which merges adds/subs preceding/following a
strd/ldrd instruction into an strd/ldrd instruction with writeback where
possible.
Differential Revision: http://reviews.llvm.org/D10676
llvm-svn: 242743
Re-apply r241926 with an additional check that r13 and r15 are not used
for LDRD/STRD. See http://llvm.org/PR24190. This also already includes
the fix from r241951.
Differential Revision: http://reviews.llvm.org/D10623
llvm-svn: 242742
whether register r9 should be reserved.
This change is needed because we cannot use a backend option to set
cl::opt "arm-reserve-r9" when doing LTO.
Out-of-tree projects currently using cl::opt option "-arm-reserve-r9" to
reserve r9 should make changes to add subtarget feature "reserve-r9" to
the IR.
rdar://problem/21529937
Differential Revision: http://reviews.llvm.org/D11320
llvm-svn: 242737
Even though this is just some hinting for the scheduler it doesn't make
sense to do that unless you know the target can perform the fusion.
llvm-svn: 242732
This patch does the following:
* Fix FIXME on `needsStackRealignment`: it is now shared between multiple targets, implemented in `TargetRegisterInfo`, and isn't `virtual` anymore. This will break out-of-tree targets, silently if they used `virtual` and with a build error if they used `override`.
* Factor out `canRealignStack` as a `virtual` function on `TargetRegisterInfo`, by default only looks for the `no-realign-stack` function attribute.
Multiple targets duplicated the same `needsStackRealignment` code:
- Aarch64.
- ARM.
- Mips almost: had extra `DEBUG` diagnostic, which the default implementation now has.
- PowerPC.
- WebAssembly.
- x86 almost: has an extra `-force-align-stack` option, which the default implementation now has.
The default implementation of `needsStackRealignment` used to just return `false`. My current patch changes the behavior by simply using the above shared behavior. This affects:
- AMDGPU
- BPF
- CppBackend
- MSP430
- NVPTX
- Sparc
- SystemZ
- XCore
- Out-of-tree targets
This is a breaking change! `make check` passes.
The only implementation of the `virtual` function (besides the slight different in x86) was Hexagon (which did `MF.getFrameInfo()->getMaxAlignment() > 8`), and potentially some out-of-tree targets. Hexagon now uses the default implementation.
`needsStackRealignment` was being overwritten in `<Target>GenRegisterInfo.inc`, to return `false` as the default also did. That was odd and is now gone.
Reviewers: sunfish
Subscribers: aemerson, llvm-commits, jfb
Differential Revision: http://reviews.llvm.org/D11160
llvm-svn: 242727
Summary:
Arguments to llvm.localescape must be static allocas. They must be at
some statically known offset from the frame or stack pointer so that
other functions can access them with localrecover.
If we ever want to instrument these, we can use more indirection to
recover the addresses of these local variables. We can do it during
clang irgen or with the asan module pass.
Reviewers: eugenis
Subscribers: llvm-commits
Differential Revision: http://reviews.llvm.org/D11307
llvm-svn: 242726
Before creating a schedule edge to encourage MacroOpFusion check that:
- The predecessor actually writes a register that the branch reads.
- The predecessor has no successors in the ScheduleDAG so we can
schedule it in front of the branch.
This avoids skewing the scheduling heuristic in cases where macroop
fusion cannot happen.
Differential Revision: http://reviews.llvm.org/D10745
llvm-svn: 242723
If objects or executables did not contain any RPATH, grep would return
nonzero, and the whole stage comparison loop would unexpectedly exit.
Fix this by checking the grep result explicitly.
llvm-svn: 242722
This is the first step toward supporting shrink-wrapping for this target.
The changes could be summarized by these items:
- Expand the tail-call return as part of the expand pseudo pass.
- Get rid of the assumptions that the epilogue is the exit block:
* Do not assume which registers are free in the epilogue. (This indirectly
improve the lowering of the code for the segmented stacks, see the test
cases.)
* Take into account that the basic block can be empty.
Related to <rdar://problem/20821730>
llvm-svn: 242714
Summary:
[NVPTX] make load on global readonly memory to use ldg
Summary:
As describe in [1], ld.global.nc may be used to load memory by nvcc when
__restrict__ is used and compiler can detect whether read-only data cache
is safe to use.
This patch will try to check whether ldg is safe to use and use them to
replace ld.global when possible. This change can improve the performance
by 18~29% on affected kernels (ratt*_kernel and rwdot*_kernel) in
S3D benchmark of shoc [2].
Patched by Xuetian Weng.
[1] http://docs.nvidia.com/cuda/kepler-tuning-guide/#read-only-data-cache
[2] https://github.com/vetter/shoc
Test Plan: test/CodeGen/NVPTX/load-with-non-coherent-cache.ll
Reviewers: jholewinski, jingyue
Subscribers: jholewinski, llvm-commits
Differential Revision: http://reviews.llvm.org/D11314
llvm-svn: 242713
This commit implements the initial serialization of machine constant pools and
the constant pool index machine operands. The constant pool is serialized using
a YAML sequence of YAML mappings that represent the constant values.
The target-specific constant pool items aren't serialized by this commit.
Reviewers: Duncan P. N. Exon Smith
llvm-svn: 242707
Re-landing r242059 which re-landed r241621... I'm really bad at this.
Summary (r242059):
This change re-lands r241621, with an additional fix that was required to allow tool sources to live outside the llvm checkout. It also no longer renames LLVM_EXTERNAL_*_SOURCE_DIR. This change was reverted in r241663, because it renamed several variables of the format LLVM_EXTERNAL_*_* to LLVM_TOOL_*_*.
Summary (r241621):
The tools CMakeLists file already had implicit tool registration, but there were a few things off about it that needed to be altered to make it work. This change addresses all that. The changes in this patch are:
* factored out canonicalizing tool names from paths to CMake variables * removed the LLVM_IMPLICIT_PROJECT_IGNORE mechanism in favor of LLVM_EXTERNAL_${nameUPPER}_BUILD which I renamed to LLVM_TOOL_${nameUPPER}_BUILD because it applies to internal and external tools
* removed ignore_llvm_tool_subdirectory() in favor of just setting LLVM_TOOL_${nameUPPER}_BUILD to Off
* Added create_llvm_tool_options() to resolve a bug in add_llvm_external_project() - the old LLVM_EXTERNAL_${nameUPPER}_BUILD would not work on a clean CMake directory because the option could be created after it was set in code.
* Removed all but the minimum required calls to add_llvm_external_project from tools/CMakeLists.txt
Differential Revision: http://reviews.llvm.org/D10665
llvm-svn: 242705
Summary:
This change generalizes the implicit null checks pass to work with
instructions that don't have any explicit register defs. This lets us
use X86's `cmp` against memory as faulting load instructions.
Reviewers: reames, JosephTremoulet
Subscribers: llvm-commits
Differential Revision: http://reviews.llvm.org/D11286
llvm-svn: 242703
This commit extends the machine instruction lexer and implements support for
the quoted global value tokens. With this change the syntax for the global value
identifier tokens becomes identical to the syntax for the global identifier
tokens from the LLVM's assembly language.
Reviewers: Duncan P. N. Exon Smith
llvm-svn: 242702
The MSys 2 version of 'env' cannot be used to set 'TZ' in the
environment due to some portability hacks in the process spawning
compatibility layer[1]. This affects test/Object/archive-toc.test, which
tries to set TZ in the environment.
Other than that, this saves a subprocess invocation of a small unix
utility, which is makes the tests faster.
The internal shell does not support shell variable expansion, so this
idiom in the ASan tests isn't supported yet:
RUN: env ASAN_OPTIONS=$ASAN_OPTIONS:opt=1 ...
[1] https://github.com/Alexpux/MSYS2-packages/issues/294
Differential Revision: http://reviews.llvm.org/D11350
llvm-svn: 242696
Summary:
1. Fix return value in `SparseBitVector::operator&=`.
2. Add checks if SBV is being assigned is invoking SBV.
Reviewers: dberlin
Subscribers: llvm-commits
Differential Revision: http://reviews.llvm.org/D11342
Committed on behalf of sl@
llvm-svn: 242693
Summary:
The MUBUF addr64 bit has been removed on VI, so we must use FLAT
instructions when the pointer is stored in VGPRs.
Reviewers: arsenm
Subscribers: llvm-commits
Differential Revision: http://reviews.llvm.org/D11067
llvm-svn: 242673
llvm-readobj exists for testing llvm. We can safely stop the program
the first time we know the input in corrupted.
This is in preparation for making it handle a few more broken files.
llvm-svn: 242656
Reordered the data tables at the top and placed the lookups after. The first stage in the yak shaving necessary to get more accurate costs for a variety of targets given the recent improvements to SINT_TO_FP/UINT_TO_FP/SIGN_EXTEND vector lowering.
llvm-svn: 242643
Not sure if the optimizer will save the call as getCalledFunction()
is not a trivial access function but the code is clearer this way.
llvm-svn: 242641
We don't bitcast the UNDEFs - that is done in visitVECTOR_SHUFFLE, and the getValueType should come from the operand's SDValue not the SDNode.
llvm-svn: 242640
canFoldMemoryOperand is not actually used anywhere in the codebase - all existing users instead call foldMemoryOperand directly when they wish to fold and can correctly deduce what they need from the return value.
This patch removes the canFoldMemoryOperand base function and the target implementations; only x86 had a real (bit-rotted) implementation, although AMDGPU had a preparatory stub that had never needed to be completed.
Differential Revision: http://reviews.llvm.org/D11331
llvm-svn: 242638
SKX supports conversion for all FP types. Integer types include doublewords and quardwords.
I added "Legal" status for these nodes and a bunch of tests.
I added "NoVLX" for AVX DAG selection to force VLX instructions selection when VLX is supported.
Differential Revision: http://reviews.llvm.org/D11255
llvm-svn: 242637
Summary: This patch allows executeCommand to pass a string to the processes stdin.
Reviewers: ddunbar, jroelofs
Subscribers: llvm-commits
Differential Revision: http://reviews.llvm.org/D11332
llvm-svn: 242631
The standard containers are not designed to be inherited from, as
illustrated by the MSVC hacks for NodeOrdering. No functional change
intended.
llvm-svn: 242616
directly model in the new PM.
This also was an incredibly brittle and expensive update API that was
never fully utilized by all the passes that claimed to preserve AA, nor
could it reasonably have been extended to all of them. Any number of
places add uses of values. If we ever wanted to reliably instrument
this, we would want a callback hook much like we have with ValueHandles,
but doing this for every use addition seems *extremely* expensive in
terms of compile time.
The only user of this update mechanism is GlobalsModRef. The idea of
using this to keep it up to date doesn't really work anyways as its
analysis requires a symmetric analysis of two different memory
locations. It would be very hard to make updates be sufficiently
rigorous to *guarantee* symmetric analysis in this way, and it pretty
certainly isn't true today.
However, folks have been using GMR with this update for a long time and
seem to not be hitting the issues. The reported issue that the update
hook fixes isn't even a problem any more as other changes to
GetUnderlyingObject worked around it, and that issue stemmed from *many*
years ago. As a consequence, a prior patch provided a flag to control
the unsafe behavior of GMR, and this patch removes the update mechanism
that has questionable compile-time tradeoffs and is causing problems
with moving to the new pass manager. Note the lack of test updates --
not one test in tree actually requires this update, even for a contrived
case.
All of this was extensively discussed on the dev list, this patch will
just enact what that discussion decides on. I'm sending it for review in
part to show what I'm planning, and in part to show the *amazing* amount
of work this avoids. Every call to the AA here is something like three
to six indirect function calls, which in the non-LTO pipeline never do
any work! =[
Differential Revision: http://reviews.llvm.org/D11214
llvm-svn: 242605
Instrumentation and the runtime library were in disagreement about
ASan shadow offset on Android/AArch64.
This fixes a large number of existing tests on Android/AArch64.
llvm-svn: 242595
Reapply r242500 now that the swift schedmodel includes LDRLIT.
This is mostly done to disable the PostRAScheduler which optimizes for
instruction latencies which isn't a good fit for out-of-order
architectures. This also allows to leave out the itinerary table in
swift in favor of the SchedModel ones.
This change leads to performance improvements/regressions by as much as
10% in some benchmarks, in fact we loose 0.4% performance over the
llvm-testsuite for reasons that appear to be unknown or out of the
compilers control. rdar://20803802 documents the investigation of
these effects.
While it is probably a good idea to perform the same switch for the
other ARM out-of-order CPUs, I limited this change to swift as I cannot
perform the benchmark verification on the other CPUs.
Differential Revision: http://reviews.llvm.org/D10513
llvm-svn: 242588
These pseudo instructions are only lowered after register allocation and
are therefore still present when the machine scheduler runs.
Add a run: line to a testcase that uses the uncommon flags necessary to
actually produce a LDRLIT instruction on swift.
llvm-svn: 242587
The idea of deferred spilling is to delay the insertion of spill code until the
very end of the allocation. A "candidate" to spill variable might not required
to be spilled because of other evictions that happened after this decision was
taken. The spirit is similar to the optimistic coloring strategy implemented in
Preston and Briggs graph coloring algorithm.
For now, this feature is highly experimental. Although correct, it would require
much more modification to properly model the effect of spilling.
Anyway, this early patch helps prototyping this feature.
Note: The test case cannot unfortunately be reduced and is probably fragile.
llvm-svn: 242585
This commit modifies the machine instruction lexer so that it now accepts the
'$' characters in identifier tokens.
This change makes the syntax for unquoted global value tokens consistent with
the syntax for the global idenfitier tokens in the LLVM's assembly language.
llvm-svn: 242584
This commit extends the interface provided by the AsmParser library by adding a
function that allows the user to parse a standalone contant value.
This change is useful for MIR serialization, as it will allow the MIR Parser to
parse the constant values in a machine constant pool.
Reviewers: Duncan P. N. Exon Smith
Differential Revision: http://reviews.llvm.org/D10280
llvm-svn: 242579
This -warn-error flag invariably gets into release tarballs
and breaks builds on distributions that run tests as a part
of release process. The OCaml binding tests are especially
critical, since they often expose lingering toolchain bugs,
and so it is replaced with -w +A (equivalent to -Wall).
llvm-svn: 242550
- Changed the default FPU of cortex-m4.
- Removed "cortex-m4f" entry. Currently not supported.
Change-Id: I73121e358aa9e7ba68eb001c2143df390ff2352a
Phabricator: http://reviews.llvm.org/D11100
llvm-svn: 242528
This is mainly for the benefit of GlobalMerge, so that an alias into a
MergedGlobals variable has the same size as the original non-merged
variable.
Differential Revision: http://reviews.llvm.org/D10837
llvm-svn: 242520
Summary:
Adds '--svn-path BRANCH' that causes the script to export the specified path
from each project. Otherwise the tag specified by -release, -rc, etc. will be
used. The version portion of the package name will be 'test-$path' (any forward
slashes in the branch name are replaced with underscores), for example:
-svn-path trunk => clang+llvm-test-trunk-mips-linux-gnu.tar.xz
-svn-path branches/release_35 => clang+llvm-test-branches_release_35-mips-linux-gnu.tar.xz
This is primarily useful for bringing new release packages up to standard
without needing to create and maintain a tag for the purpose.
Reviewers: tstellarAMD, hans
Subscribers: llvm-commits
Differential Revision: http://reviews.llvm.org/D6563
llvm-svn: 242518
basic changes to the IR such as folding pointers through PHIs, Selects,
integer casts, store/load pairs, or outlining.
This leaves the feature available behind a flag. This flag's default
could be flipped if necessary, but the real-world performance impact of
this particular feature of GMR may not be sufficiently significant for
many folks to want to run the risk.
Currently, the risk here is somewhat mitigated by half-hearted attempts
to update GlobalsModRef when the rest of the optimizer changes
something. However, I am currently trying to remove that update
mechanism as it makes migrating the AA infrastructure to a form that can
be readily shared between new and old pass managers very challenging.
Without this update mechanism, it is possible that this still unlikely
failure mode will start to trip people, and so I wanted to try to
proactively avoid that.
There is a lengthy discussion on the mailing list about why the core
approach here is flawed, and likely would need to look totally different
to be both reasonably effective and resilient to basic IR changes
occuring. This patch is essentially the first of two which will enact
the result of that discussion. The next patch will remove the current
update mechanism.
Thanks to lots of folks that helped look at this from different angles.
Especial thanks to Michael Zolotukhin for doing some very prelimanary
benchmarking of LTO without GlobalsModRef to get a rough idea of the
impact we could be facing here. So far, it looks very small, but there
are some concerns lingering from other benchmarking. The default here
may get flipped if performance results end up pointing at this as a more
significant issue.
Also thanks to Pete and Gerolf for reviewing!
Differential Revision: http://reviews.llvm.org/D11213
llvm-svn: 242512
In particular, it's much easier to read, as it doesn't expand all
the way on wide-screen displays.
CSS committed under LLVM license with explicit permission from
Daniel Bünzli <daniel.buenzli@erratique.ch>.
llvm-svn: 242511
Since r230724 ("Skip promotable allocas to improve performance at -O0"), there is a regression in the generated debug info for those non-instrumented variables. When inspecting such a variable's value in LLDB, you often get garbage instead of the actual value. ASan instrumentation is inserted before the creation of the non-instrumented alloca. The only allocas that are considered standard stack variables are the ones declared in the first basic-block, but the initial instrumentation setup in the function breaks that invariant.
This patch makes sure uninstrumented allocas stay in the first BB.
Differential Revision: http://reviews.llvm.org/D11179
llvm-svn: 242510
This is mostly done to disable the PostRAScheduler which optimizes for
instruction latencies which isn't a good fit for out-of-order
architectures. This also allows to leave out the itinerary table in
swift in favor of the SchedModel ones.
This change leads to performance improvements/regressions by as much as
10% in some benchmarks, in fact we loose 0.4% performance over the
llvm-testsuite for reasons that appear to be unknown or out of the
compilers control. rdar://20803802 documents the investigation of
these effects.
While it is probably a good idea to perform the same switch for the
other ARM out-of-order CPUs, I limited this change to swift as I cannot
perform the benchmark verification on the other CPUs.
Differential Revision: http://reviews.llvm.org/D10513
llvm-svn: 242500
Those new constructors make it more natural to construct an object for a function. For example, previously to build a LoopInfo for a function, we need four statements:
DominatorTree DT;
LoopInfo LI;
DT.recalculate(F);
LI.analyze(DT);
Now we only need one statement:
LoopInfo LI(DominatorTree(F));
http://reviews.llvm.org/D11274
llvm-svn: 242486
Constructing a name based on the function name didn't give us a unique
symbol if we had more than one setjmp in a function. Using
MCContext::createTempSymbol() always gives us a unique name.
Differential Revision: http://reviews.llvm.org/D9314
llvm-svn: 242482
llvm.eh.sjlj.setjmp was used as part of the SjLj exception handling
style but is also used in clang to implement __builtin_setjmp. The ARM
backend needs to output additional dispatch tables for the SjLj
exception handling style, these tables however can't be emitted if
llvm.eh.sjlj.setjmp is simply used for __builtin_setjmp and no actual
landing pad blocks exist.
To solve this issue a new llvm.eh.sjlj.setup_dispatch intrinsic is
introduced which is used instead of llvm.eh.sjlj.setjmp in the SjLj
exception handling lowering, so we can differentiate between the case
where we actually need to setup a dispatch table and the case where we
just need the __builtin_setjmp semantic.
Differential Revision: http://reviews.llvm.org/D9313
llvm-svn: 242481
C11 leaves the choice on whether round-to-integer operations set the inexact
flag implementation-defined. Darwin does expect it to be set, but this seems to
be against the intent of the IEEE document and slower to implement anyway. So
it should be opt-in.
llvm-svn: 242446
I was looking at some vector code generation and kept seeing
unnecessary vector copies into the Altivec half of the VSX registers.
I discovered that we overlooked v4i32 when adding the register classes
for VSX; we only added v4f32 and v2f64. This means that anything that
canonicalizes into v4i32 (which is a LOT of stuff) ends up being
forced into VRRC on its way to VSRC.
The fix is one line. The rest of the patch is fixing up some test
cases whose code generation has changed as a result.
This seems like it would be a good candidate for backport to 3.7.
llvm-svn: 242442
Summary:
SpeculativeExecution enables a series straight line optimizations (such
as SLSR and NaryReassociate) on conditional code. For example,
if (...)
... b * s ...
if (...)
... (b + 1) * s ...
speculative execution can hoist b * s and (b + 1) * s from then-blocks,
so that we have
... b * s ...
if (...)
...
... (b + 1) * s ...
if (...)
...
Then, SLSR can rewrite (b + 1) * s to (b * s + s) because after
speculative execution b * s dominates (b + 1) * s.
The performance impact of this change is significant. It speeds up the
benchmarks running EigenFloatContractionKernelInternal16x16
(ba68f42fa6/unsupported/Eigen/CXX11/src/Tensor/TensorContractionCuda.h?at=default#cl-526)
by roughly 2%. Some internal benchmarks that have the above code pattern
are improved by up to 40%. No significant slowdowns are observed on
Eigen CUDA microbenchmarks.
Reviewers: jholewinski, broune, eliben
Subscribers: llvm-commits, jholewinski
Differential Revision: http://reviews.llvm.org/D11201
llvm-svn: 242437
This is a new iteration of the reverted r238793 /
http://reviews.llvm.org/D8232 which wrongly assumed that any and/or
trees can be represented by conditional compare sequences, however there
are some restrictions to that. This version fixes this and adds comments
that explain exactly what types of and/or trees can actually be
implemented as conditional compare sequences.
Related to http://llvm.org/PR20927, rdar://18326194
Differential Revision: http://reviews.llvm.org/D10579
llvm-svn: 242436
Summary:
We can safely assume that the high bit of scratch offsets will never
be set, because this would require at least 128 GB of GPU memory.
Reviewers: arsenm
Subscribers: llvm-commits
Differential Revision: http://reviews.llvm.org/D11225
llvm-svn: 242433
Empty subranges are not allowed in a LiveInterval and must be removed
instead: Check this in the verifiers, put a reminder for this in the
comment of the shrinkToUses variant for a single lane and make it
automatic for the shrinkToUses variant for a LiveInterval.
llvm-svn: 242431
This reverts commit r242300.
This is causing buildbot failures which we are investigating.
I'll reapply once we know whats going on, but for now want to
get the bots green.
llvm-svn: 242428
The benefit of turning the parameter of LoopInfo::analyze() to const& is that it now can accept a rvalue.
http://reviews.llvm.org/D11250
llvm-svn: 242426
Internalizing an individual comdat group member without also internalizing
the other members of the comdat can break comdat semantics. For example,
if a module contains a reference to an internalized comdat member, and the
linker chooses a comdat group from a different object file, this will break
the reference to the internalized member.
This change causes the internalizer to only internalize comdat members if all
other members of the comdat are not externally visible. Once a comdat group
has been fully internalized, there is no need to apply comdat rules to its
members; later optimization passes (e.g. globaldce) can legally drop individual
members of the comdat. So we drop the comdat attribute from all comdat members.
Differential Revision: http://reviews.llvm.org/D10679
llvm-svn: 242423
Summary:
This change is part of a series of commits dedicated to have a single
DataLayout during compilation by using always the one owned by the
module.
The ExecutionEngine will act as an exception and will be unsafe to
be reused across context. We don't enforce this rule but undefined
behavior can occurs if the user tries to do it.
Reviewers: lhames
Subscribers: echristo, llvm-commits, rafael, yaron.keren
Differential Revision: http://reviews.llvm.org/D11110
From: Mehdi Amini <mehdi.amini@apple.com>
llvm-svn: 242414
Summary:
This fixes an issue on MIPS where the infinite-loop-evergreen.ll test
was failing to terminate.
Fixes PR24147.
Reviewers: arsenm, dsanders
Subscribers: llvm-commits
Differential Revision: http://reviews.llvm.org/D11260
llvm-svn: 242410
This adds new intrinsics "*absdiff" for absolute difference ops to facilitate efficient code generation for "sum of absolute differences" operation.
The patch also contains the introduction of corresponding SDNodes and basic legalization support.Sanity of the generated code is tested on X86.
This is 1st of the three patches.
Patch by Shahid Asghar-ahmad!
llvm-svn: 242409
- ARM V7L matches the 'A' profile of ARM architecture.
Change-Id: I80c8b973f5c93fb040c177a227644d56b1b83ea8
Phabricator: http://reviews.llvm.org/D11261
llvm-svn: 242406
Summary:
The checking pointer grouping algorithm assumes that the
starts/ends of the pointers are well formed (start <= end).
The runtime memory checking algorithm also assumes this by doing:
start0 < end1 && start1 < end0
to detect conflicts. This check only works if start0 <= end0 and
start1 <= end1.
This change correctly orders the interval ends by either checking
the stride (if it is constant) or by using min/max SCEV expressions.
Reviewers: anemet, rengolin
Subscribers: rengolin, llvm-commits
Differential Revision: http://reviews.llvm.org/D11149
llvm-svn: 242400
This allows more call sequences to use pushes instead of movs when optimizing for size.
In particular, calling conventions that pass some parameters in registers (e.g. thiscall) are now supported.
This should no longer cause miscompiles, now that a bug in emitPrologue was fixed in r242395.
llvm-svn: 242398
When X86FrameLowering::emitPrologue() looks for where to insert the %esp subtraction
to allocate stack space for local allocations, it assumes that any sequence of push
instructions that starts at function entry consists purely of spills of callee-save
registers.
This may be false, since from some point forward, the pushes may pushing arguments
to a subsequent function call.
This caused a miscompile that was exposed by r240257, and is not easily testable
since r240257 was reverted. A test will be committed separately after r240257 is
reapplied.
llvm-svn: 242395
Summary:
This change is part of a series of commits dedicated to have a single
DataLayout during compilation by using always the one owned by the
module.
The ExecutionEngine will act as an exception and will be unsafe to
be reused across context. We don't enforce this rule but undefined
behavior can occurs if the user tries to do it.
Reviewers: lhames
Subscribers: echristo, llvm-commits, rafael, yaron.keren
Differential Revision: http://reviews.llvm.org/D11110
From: Mehdi Amini <mehdi.amini@apple.com>
llvm-svn: 242387
Summary:
This change is part of a series of commits dedicated to have a single
DataLayout during compilation by using always the one owned by the
module.
This patch is quite boring overall, except for some uglyness in
ASMPrinter which has a getDataLayout function but has some clients
that use it without a Module (llmv-dsymutil, llvm-dwarfdump), so
some methods are taking a DataLayout as parameter.
Reviewers: echristo
Subscribers: yaron.keren, rafael, llvm-commits, jholewinski
Differential Revision: http://reviews.llvm.org/D11090
From: Mehdi Amini <mehdi.amini@apple.com>
llvm-svn: 242386
Summary:
This change is part of a series of commits dedicated to have a single
DataLayout during compilation by using always the one owned by the
module.
Reviewers: echristo
Subscribers: yaron.keren, rafael, llvm-commits, jholewinski
Differential Revision: http://reviews.llvm.org/D11079
From: Mehdi Amini <mehdi.amini@apple.com>
llvm-svn: 242385
Summary:
Because llvm-dsymutil is using ASMPrinter without any MachineFunction
of Module available.
This change is part of a series of commits dedicated to have a single
DataLayout during compilation by using always the one owned by the
module.
Reviewers: echristo
Subscribers: yaron.keren, rafael, llvm-commits
Differential Revision: http://reviews.llvm.org/D11078
From: Mehdi Amini <mehdi.amini@apple.com>
llvm-svn: 242384
This is made a static public member function to allow the transition of
this logic from LAA to LoopDistribution. (Technically, it could be an
implementation-local static function but then it would not be accessible
from LoopDistribution.)
llvm-svn: 242376
Revert the changes to the C API LLVMBuildLandingPad that were part of
the personality function move. We now set the personality on the parent
function when the C API attempts to construct a landingpad with a
personality.
This reverts commit r240010.
llvm-svn: 242372
The testcase failed on non X86 targets, because I forgot to pass the
'-march=x86-64' option into llc for one of the X86 specific tests.
llvm-svn: 242370
pairs for 32-bit immediates.
This change is needed to avoid emitting movt/movw pairs when doing LTO
and do so on a per-function basis.
Out-of-tree projects currently using cl::opt option -arm-use-movt=0 or
false to avoid emitting movt/movw pairs should make changes to add
subtarget feature "+no-movt" (see the changes made to clang in r242368).
rdar://problem/21529937
Differential Revision: http://reviews.llvm.org/D11026
llvm-svn: 242369
The pass here was clearing kill flags on instructions which had
their sources killed in the instruction being combined. But
given that the new instruction is inserted after the existing ones,
any existing instructions with kill flags will lead to the verifier
complaining that we are reading an undefined physreg.
For example, what we had prior to this optimization is
t2STRi12 %R1, %SP, 12
t2STRi12 %R1<kill>, %SP, 16
t2STRi12 %R0<kill>, %SP, 8
and prior to this fix that would generate
t2STRi12 %R1<kill>, %SP, 16
t2STRDi8 %R0<kill>, %R1, %SP, 8
This is clearly incorrect as it didn't clear the kill flag on R1
used with offset 16 because there was no kill flag on the instruction
with offset 12.
After this change we clear the kill flag on the offset 16 instruction
because we know it will be used afterwards in the new instruction.
I haven't provided a test case. I have a small test, but even it is
very sensitive to register allocation order which isn't ideal.
llvm-svn: 242359
The jump table info is serialized using a YAML mapping that contains its kind
and a YAML sequence of jump table entries. A jump table entry is a YAML mapping
that has an ID and an inline YAML sequence of machine basic block references.
The testcase 'CodeGen/MIR/X86/jump-table-info.mir' doesn't have any instructions
because one of them contains a jump table index operand. The jump table index
operands will be serialized in a follow up patch, and the appropriate
instructions will be added to this testcase.
Reviewers: Duncan P. N. Exon Smith
llvm-svn: 242357
This new wrapper pass is useful when we want to do branch probability analysis conditionally (e.g. only in PGO mode) but don't want to add one more pass dependence.
http://reviews.llvm.org/D11241
llvm-svn: 242349
Summary:
This is a trivial code change with no functionality effect.
When LoopUnswitch determines trivial unswitch condition, it checks whether the loop header's terminator instruction is a branch instruction or switch instruction since trivial unswitch condition can only apply to these two instruction types. The current code does not fail the check directly on other instruction types, but check the nullness of LoopExitBB variable instead. The added else clause makes the check fail immediately on other instruction types and makes the code more obvious.
Reviewers: reames
Subscribers: llvm-commits
Differential Revision: http://reviews.llvm.org/D11239
llvm-svn: 242345
On some systems (e.g. Mac OS X), sed will add a newline to the end of
the output if there wasn't one already. This would cause false
cmp errors since the .o file from Phase 2 was passed through sed and
the one from Phase 3 wasn't. Work around this by passing both through
sed.
llvm-svn: 242341
Pass a const reference to LiveRegMatrix to getRegAllocationHints()
because some targets can prodive better hints if they can test whether a
physreg has been used for register allocation yet.
llvm-svn: 242340
This commit serializes the references to the named LLVM alloca instructions from
the stack objects in the machine frame info. This commit adds a field 'Name' to
the struct 'yaml::MachineStackObject'. This new field is used to store the name
of the alloca instruction when the alloca is present and when it has a name.
llvm-svn: 242339
emit debug info, according to the preferences of the different
debuggers used on various targets.
Darwin and FreeBSD default to tuning for LLDB; PS4 defaults to tuning for
the SCE (Sony Computer Entertainment) debugger. All others default to GDB.
Differential Revision: http://reviews.llvm.org/D8506
llvm-svn: 242338
Self-referential constants containing references to a merged function
no longer cause the MergeFunctions pass to infinite loop. Also adds a
reproduction IR which would otherwise fail, which was isolated from a similar
issue in Chromium.
Author: jrkoenig
Reviewers: nlewycky, jfb
Subscribers: llvm-commits, nlewycky, jfb
Differential Revision: http://reviews.llvm.org/D11208
llvm-svn: 242337
It retains the possibility to use the autoconf build with a
command-line option ('-use-autoconf'), and uses that by default on Darwin since
compiler-rt requires it on that platform.
This commit also removes the "Release-64" flavour and related logic. The script
would previously do two builds unless the '-no-64bit' flag was passed, but on
my machine and from those I asked this always ended up producing two 64-bit builds,
causing much confusion.
It also removes the -build-triple option, which caused the --build= flag to
get passed to ./configure. This was presumably intended for cross-compiling,
but none of the release testers use it. If someone does want to pass it,
they can use '-configure-flags --build=foo' instead.
Differential Revision: http://reviews.llvm.org/D10715
llvm-svn: 242331
Summary:
This patch allows phi nodes like
%x = phi [ %incptr, ... ] [ %var, ... ]
%incptr = getelementptr %x, 1
to be analyzed by BasicAliasAnalysis.
In aliasPHI, we can detect incoming values that are recursive GEPs with a
constant offset. Instead of trying to analyze a recursive GEP (and failing),
we now ignore it and instead set the size of the memory referenced by
the PHINode to UnknownSize. This represents all the possible memory
locations the pointer represented by the PHINode could be advanced to
by the GEP.
For now, this new behavior is turned off by default to allow debugging of
performance degradations seen with SPEC/x86 and Hexagon benchmarks.
The flag -basicaa-recphi turns it on.
Reviewers: hfinkel, sanjoy
Subscribers: tobiasvk_caf, sanjoy, llvm-commits
Differential Revision: http://reviews.llvm.org/D10368
llvm-svn: 242320
This is a necessary prerequisite for bootstrapping the emission
of debug info inside modules.
- Adds a FlagExternalTypeRef to DICompositeType.
External types must have a unique identifier.
- External type references are emitted using a forward declaration
with a DW_AT_signature([DW_FORM_ref_sig8]) based on the UID.
http://reviews.llvm.org/D9612
llvm-svn: 242302
These were the cause of a verifier error when building 7zip with
-verify-machineinstrs. Running 'make check' with the verifier
triggered the same error on the test here so i've updated the test
to run the verifier on one of its runs instead of adding a new one.
While looking at this code, there was a stale comment that these
instructions were only used for disassembly. This probably used to
be the case, but they are now used in the 'ARM load / store optimization pass' too.
llvm-svn: 242300
The vec_sld interface provides access to the vsldoi instruction.
Unlike most of the vec_* interfaces, we do not attempt to change the
generated code for vec_sld based on the endian mode. It is too
difficult to correctly infer the desired semantics because of
different element types, and the corrected instruction sequence is
expensive, involving loading a permute control vector and performing a
generalized permute.
For GCC, this was implemented as "Don't touch the vec_sld"
implementation. When it came time for the LLVM implementation, I did
the same thing. However, this was hasty and incorrect. In LLVM's
version of altivec.h, vec_sld was previously defined in terms of the
vec_perm interface. Because vec_perm semantics are adjusted for
little endian, this means that leaving vec_sld untouched causes it to
generate something different for LE than for BE. Not good.
This back-end patch accompanies the changes to altivec.h that change
vec_sld's behavior for little endian. Those changes mean that we see
slightly different code in the back end when trying to recognize a
VSLDOI instruction in isVSLDOIShuffleMask. In particular, a
ShuffleKind of 1 (where the two inputs are identical) must now be
treated the same way as a ShuffleKind of 2 (little endian with
different inputs) when little endian mode is in force. This is
because ShuffleKind of 1 is defined using big-endian numbering.
This has a ripple effect on LowerBUILD_VECTOR, where we create our own
internal VSLDOI instructions. Because these are a ShuffleKind of 1,
they will now have their shift amounts subtracted from 16 when
recognizing the shuffle mask. To avoid problems we have to subtract
them from 16 again before creating the VSLDOI instructions.
There are a couple of other uses of BuildVSLDOI, but these do not need
to be modified because the shift amount is 8, which is unchanged when
subtracted from 16.
llvm-svn: 242296
- Teaches the ValueTracker in the PeepholeOptimizer to look through PHI
instructions.
- Add findNextSourceAndRewritePHI method to lookup into multiple sources
returnted by the ValueTracker and rewrite PHIs with new sources.
With these changes we can find more register sources and rewrite more
copies to allow coaslescing of bitcast instructions. Hence, we eliminate
unnecessary VR64 <-> GR64 copies in x86, but it could be extended to
other archs by marking "isBitcast" on target specific instructions. The
x86 example follows:
A:
psllq %mm1, %mm0
movd %mm0, %r9
jmp C
B:
por %mm1, %mm0
movd %mm0, %r9
jmp C
C:
movd %r9, %mm0
pshufw $238, %mm0, %mm0
Becomes:
A:
psllq %mm1, %mm0
jmp C
B:
por %mm1, %mm0
jmp C
C:
pshufw $238, %mm0, %mm0
Differential Revision: http://reviews.llvm.org/D11197
rdar://problem/20404526
llvm-svn: 242295
- Create a new CopyRewriter for Uncoalescable copy-like instructions
- Change the ValueTracker to return a ValueTrackerResult
This makes optimizeUncoalescable looks more like optimizeCoalescable and
use the CopyRewritter infrastructure.
This is also the preparation for looking up into PHI nodes in the
ValueTracker.
Differential Revision: http://reviews.llvm.org/D11195
llvm-svn: 242294
Summary:
Add Value.SetPersonality to the Go bindings. The Go
bindings' Builder.CreateLandingPad has been updated,
removing the obsolete personality argument.
Background
The personality attribute was removed from LandingPadInst
in r239940, and llvm::Function::setPersonalityFn introduced.
There was no corresponding change to either the C API or
Go bindings. The Go bindings were broken until r239940, but
that change was just to ignore the personality argument.
This broke llgo.
Reviewers: majnemer, pcc
Subscribers: deadalnix, llvm-commits, axw
Differential Revision: http://reviews.llvm.org/D11116
llvm-svn: 242289
inspection.
While we want to handle calls specially in this code because they should
have been modeled by the call graph analysis that precedes it, we should
*not* be re-implementing the predicates for whether an instruction reads
or writes memory. Those are well defined already. Notably, at least the
following issues seem to be clearly missed before:
- Ordered atomic loads can "write" to memory by causing writes from other
threads to become visible. Similarly for ordered atomic stores.
- AtomicRMW instructions quite obviously both read and write to memory.
- AtomicCmpXchg instructions also read and write to memory.
- Fences read and write to memory.
- Invokes of intrinsics or memory allocation functions.
I don't have any test cases, and I suspect this has never really come up
in the real world. But there is no reason why it wouldn't, and it makes
the code simpler to do this the right way.
While here, I've tried to make the loops significantly simpler as well
and added helpful comments as to what is going on.
llvm-svn: 242281
Current implementation handles unordered comparison poorly in soft-float mode.
Consider (a ULE b) which is a <= b. It is lowered to (ledf2(a, b) <= 0 || unorddf2(a, b) != 0) (in general). We can do better job by lowering it to (__gtdf2(a, b) <= 0).
Such replacement is true for other CMP's (ult, ugt, uge). In general, we just call same function as for ordered case but negate comparison against zero.
Differential Revision: http://reviews.llvm.org/D10804
llvm-svn: 242280
This is a direct port of the code from the X86 backend (r239486/r240361), which
uses the MachineCombiner to reassociate (floating-point) adds/muls to increase
ILP, to the PowerPC backend. The rationale is the same.
There is a lot of copy-and-paste here between the X86 code and the PowerPC
code, and we should extract at least some of this into CodeGen somewhere.
However, I don't want to do that until this code is enhanced to handle FMAs as
well. After that, we'll be in a better position to extract the common parts.
llvm-svn: 242279
If the source of the copy that defines the addend is a physical register, then
its existing live range may not extend to the FMA being mutated. Make sure we
extend the live range of the register to meet the FMA because it will become
its operand in this case.
I don't have an independent test case, but it will be exposed by change to be
committed shortly enabling the use of the machine combiner to do fadd/fmul
reassociation, and will be covered by one of the associated regression tests.
llvm-svn: 242278
MachineCombiner predicated its use of scheduling-based metrics on
hasInstrSchedModel(), but useful conclusions can be drawn from pipeline
itineraries as well. Almost all of the logic (except for resource tracking in
preservesResourceLen) can be used if we have an itinerary, so enable it in that
case as well.
This will be used by the PowerPC backend in an upcoming commit.
llvm-svn: 242277
Bitpatterns rejected by the decoder method of `MSR (immediate)` should be
decoded as the `extended MSR (register)` instruction.
Differential Revision: http://reviews.llvm.org/D7174
llvm-svn: 242276
When FixedLenDecoder matches an input bitpattern of form [01]+ with an
instruction bitpattern of form [01?]+ (where 0/1 are static bits and ? are
mixed/variable bits) it passes the input bitpattern to a specific instruction
decoder method which then makes a final decision whether the bitpattern is a
valid instruction or not. This means the decoder must handle all possible
values of the variable bits which sometimes leads to opcode rewrites in the
decoder method when the instructions are not fully orthogonal.
The patch provides a way for the decoder method to say that when it returns
Fail it does not necessarily mean the bitpattern is invalid, but rather that
the bitpattern is definitely not an instruction that is recognized by the
decoder method. The decoder can then try to match the input bitpattern with
other possible instruction bitpatterns.
For example, this allows to solve a situation on AArch64 where the `MSR
(immediate)` instruction has form:
1101 0101 0000 0??? 0100 ???? ???1 1111
but not all values of the ? bits are allowed. The rejected values should be
handled by the `extended MSR (register)` instruction:
1101 0101 000? ???? ???? ???? ???? ????
The decoder will first try to decode an input bitpattern that matches both
bitpatterns as `MSR (immediate)` but currently this puts the decoder method of
`MSR (immediate)` into a situation when it must be able to decode all possible
values of the ? bits, i.e. it would need to rewrite the instruction to `MSR
(register)` when it is not `MSR (immediate)`.
The patch allows to specify that the decoder method cannot determine if the
instruction is valid for all variable values. The decoder method can simply
return Fail when it knows it is definitely not `MSR (immediate)`. The decoder
will then backtrack the decoding and find that it can match the input
bitpattern with the more generic `MSR (register)` bitpattern too.
Differential Revision: http://reviews.llvm.org/D7174
llvm-svn: 242274
dejagnu.
I wonder if it would be useful to handle FileCheck prefixes specially?
Especially if we could get some error checking. Suggestions welcome.
Patches more welcome as I have no idea what I'm doing with vim
script....
llvm-svn: 242267
to intelligently wrap prose written in IR comment blocks. This has
bothered me for roughly ever, and my fellow IRC denziens convinced me to
fix it.
llvm-svn: 242266
The unsigned opcode argument here was the result of BinaryOperator->getOpcode().
That returns a BinaryOps enum which is more accurate than passing around an
unsigned.
llvm-svn: 242265