Chandler Carruth [Sun, 25 Dec 2016 08:22:50 +0000 (08:22 +0000)]
[ADT] Add a generic concatenating iterator and range.
This allows both defining convenience iterator/range accessors on types
which walk across N different independent ranges within the object, and
more direct and simple usages with range based for loops such as shown
in the unittest. The same facilities are used for both. They end up
quite small and simple as it happens.
I've also switched an iterator on `Module` to use this. I would like to
add another convenience iterator that includes even more sequences as
part of it and seeing this one already present motivated me to actually
abstract it away and introduce a general utility.
Mehdi Amini [Sun, 25 Dec 2016 04:22:54 +0000 (04:22 +0000)]
MetadataLoader: replace the tracking of ForwardReferences and UnresolvedNodes with a set-based solution (NFC)
This makes it explicit what is the exact list to handle, and it
looks much more easy to manipulate and understand that the
previous custom tracking of min/max to express the range where
to look for.
Chandler Carruth [Fri, 23 Dec 2016 23:33:35 +0000 (23:33 +0000)]
[PM] Teach the always inlining test case to be much more strict about
whether functions are removed, and fix the new PM's always inliner to
actually pass this test.
Without this, the new PM's always inliner leaves all the functions
kicking around which won't work out very well given the semantics of
always inline.
Doing this really highlights how frustrating the current alwaysinline
semantic contract is though -- why can we put it on *external*
functions, etc?
Also I've added a number of tricky and interesting test cases for
removing functions with the always inliner. There is one remaining case
not handled -- fully removing comdats -- and I've left a FIXME about
this.
Davide Italiano [Fri, 23 Dec 2016 13:12:50 +0000 (13:12 +0000)]
[LICM] Work around LICM needs to maintain state across loops.
The pass creates some state which expects to be cleaned up by
a later instance of the same pass. opt-bisect happens to expose
this not ideal design because calling skipLoop() will result in
this state not being cleaned up at times and an assertion firing
in `doFinalization()`. Chandler tells me the new pass manager will
give us options to avoid these design traps, but until it's not ready,
we need a workaround for the current pass infrastructure. Fix provided
by Andy Kaylor, see the review for a complete discussion.
According to the Cortex-A57 doc, FDIV/FSQRT instructions should use F0 unit
(W-unit in AArch64SchedA57.td, the same as cryptography instructions),
not F1 unit (X-unit in td, like ASIMD absolute diff accum SABA/UABA).
This patch changes FDIV/FSQRT scheduling declarations to use A57UnitW
instead of A57UnitX. Also, latencies for those instructions are
corrected.
Zijiao Ma [Fri, 23 Dec 2016 02:56:07 +0000 (02:56 +0000)]
Make the canonicalisation on shifts benifit to more case.
1.Fix pessimized case in FIXME.
2.Add tests for it.
3.The canonicalisation on shifts results in different sequence for
tests of machine-licm.Correct some check lines.
Chandler Carruth [Fri, 23 Dec 2016 02:02:26 +0000 (02:02 +0000)]
Fix some DOS-style line endings that I suspect snuck in from one of the
frustrating Subversion clients that fails to do line ending translation
of text files.
Don't consider allocsize functions to be allocation functions.
This patch fixes some ASAN unittest failures on FreeBSD. See the
cfe-commits email thread for r290169 for more on those.
According to the LangRef, the allocsize attribute only tells us about
the number of bytes that exist at the memory location pointed to by the
return value of a function. It does not necessarily mean that the
function will only ever allocate. So, we need to be very careful about
treating functions with allocsize as general allocation functions. This
patch makes us fully conservative in this regard, though I suspect that
we have room to be a bit more aggressive if we want.
This has a FIXME that can be fixed by a relatively straightforward
refactor; I just wanted to keep this patch minimal. If this sticks, I'll
come back and fix it in a few days.
Sanjoy Das [Fri, 23 Dec 2016 00:41:21 +0000 (00:41 +0000)]
Reimplement depedency tracking in the ImplicitNullChecks pass
Summary:
This change rewrites a core component in the ImplicitNullChecks pass for
greater simplicity since the original design was over-complicated for no
good reason. Please review this as essentially a new pass. The change
is almost NFC and I've added a test case for a scenario that this new
code handles that wasn't handled earlier.
The implicit null check pass, at its core, is a code hoisting transform.
It differs from "normal" code transforms in that it speculates
potentially faulting instructions (by design), but a lot of the usual
hazard detection logic (register read-after-write etc.) still applies.
We previously detected hazards by keeping track of registers defined and
used by machine instructions over an instruction range, but that was
unwieldy and did not actually confer any performance benefits. The
intent was to have linear time complexity over the number of machine
instructions considered, but it ended up being N^2 is practice.
This new version is more obviously O(N^2) (with N capped to 8 by
default) in hazard detection. It does not attempt to be clever in
tracking register uses or defs (the previous cleverness here was a
source of bugs).
Once this is checked in, I'll extract out the `IsSuitableMemoryOp` and
`CanHoistLoadInst` lambda into member functions (they're too complicated
to be inline lambdas) and do some other related NFC cleanups.
Chris Bieneman [Thu, 22 Dec 2016 22:44:27 +0000 (22:44 +0000)]
[ObjectYAML] Support for DWARF debug_info section
This patch adds support for YAML<->DWARF for debug_info sections.
This re-lands r290147, reverted in 290148, re-landed in r290204 after fixing the issue that caused bots to fail (thank you UBSan!), and reverted again in r290209 due to failures on big endian systems.
After adding support for preserving endianness, this should be good now.
Evgeniy Stepanov [Thu, 22 Dec 2016 22:22:35 +0000 (22:22 +0000)]
[cfi] Emit jump tables as a function-level inline asm.
Use a dummy private function with inline asm calls instead of module
level asm blocks for CFI jumptables.
The main advantage is that now jumptable codegen can be affected by
the function attributes (like target_cpu on ARM). Module level asm
gets the default subtarget based on the target triple, which is often
not good enough.
This change also uses asm constraints/arguments to reference
jumptable targets and aliases directly. We no longer do asm name
mangling in an IR pass.
Quentin Colombet [Thu, 22 Dec 2016 21:56:39 +0000 (21:56 +0000)]
[MachineVerifier] Check that even generic vregs comply to regclass constraints.
We used to not check generic vregs, but that is actually a mistake given
nothing in the GlobalISel pipeline is going to fix the constraints on
target specific instructions. Therefore, the target has to have them
right from the start.
Quentin Colombet [Thu, 22 Dec 2016 21:56:37 +0000 (21:56 +0000)]
[AArch64] Change a test to use a generic instr instead of a target specific one.
Target specific instructions have requirements that are not compatible
with what we want to test here. Namely, target specific instructions
must have their operands properly mapped on register classes.
Quentin Colombet [Thu, 22 Dec 2016 21:56:31 +0000 (21:56 +0000)]
[AArch64][CallLowering] Constraint registers on target specific instruction
The InstructionSelect pass will not look at target specific instructions
since they are already selected. As a result, the operands of target
specific instructions must be properly constrained, because it is not
going to fix them.
This fixes invalid register classes on call instruction.
Quentin Colombet [Thu, 22 Dec 2016 21:56:29 +0000 (21:56 +0000)]
[MIRParser] Non-generic virtual register may have a type.
When generic virtual registers get constrained, because of a use on a
target specific operation for instance, we end up with regular virtual
registers with a type and that's perfectly fine.
Matt Arsenault [Thu, 22 Dec 2016 21:40:08 +0000 (21:40 +0000)]
AMDGPU: Invert cmp + select with constant
Canonicalize a select with a constant to the false side. This
enables more instruction shrinking opportunities since an
inline immediate can be used for the false side of v_cndmask_b32_e32.
This seems to usually be better but causes some code size regressions
in some tests.
Wei Mi [Thu, 22 Dec 2016 19:44:45 +0000 (19:44 +0000)]
Redo store splitting in CodeGenPrepare.
This is a succeeding patch of https://reviews.llvm.org/D22840 to address the
issue when a value to be merged into an int64 pair is in a different BB. Redoing
the store splitting in CodeGenPrepare so we can match the pattern across multiple
BBs and move some instructions into the same BB. We still keep the code in dag
combine so that we can catch cases that show up after DAG combining runs.
Reid Kleckner [Thu, 22 Dec 2016 19:12:14 +0000 (19:12 +0000)]
Pass -Wa,-mbig-obj in 64-bit mingw builds
COFF has a 2**16 section limit, and on Win64, every COMDAT function
creates at least 3 sections: .text, .pdata, and .xdata. For MSVC, we
enable bigobj on a file-by-file basis, but GCC appears to hit the limit
on different files.
Fix two bugs in the pipeliner in renaming phis in the prolog and epilog
When the pipeliner is renaming phi values, it may need to iterate through
the phi operands to check for other phis. However, the pipeliner should
stop once it reaches a phi that is outside the pipelined loop.
Also, when the generateExistingPhis code is unable to reuse an existing
phi, the default code that computes the PhiOp2 is only to be used when
the pipeliner is generating the kernel. Otherwise, the phi may be a value
computed earlier in the same epilog.
Davide Italiano [Thu, 22 Dec 2016 16:03:48 +0000 (16:03 +0000)]
[GVN] Initial check-in of a new global value numbering algorithm.
The code have been developed by Daniel Berlin over the years, and
the new implementation goal is that of addressing shortcomings of
the current GVN infrastructure, i.e. long compile time for large
testcases, lack of phi predication, no load/store value numbering
etc...
The current code just implements the "core" GVN algorithm, although
other pieces (load coercion, phi handling, predicate system) are
already implemented in a branch out of tree. Once the core is stable,
we'll start adding pieces on top of the base framework.
The test currently living in test/Transform/NewGVN are a copy
of the ones in GVN, with proper `XFAIL` (missing features in NewGVN).
A flag will be added in a future commit to enable NewGVN, so that
interested parties can exercise this code easily.
Chandler Carruth [Thu, 22 Dec 2016 07:14:35 +0000 (07:14 +0000)]
[PM] Make a couple of CHECK lines a bit more precise, NFC.
I was staring at these and didn't realize these were module-layer
proxies as opposed to some other layer. Justin and I have a plan to
rename things to make the names themselves much easier to reason about,
but I at least want the CHECK lines to be precise for now.
Chandler Carruth [Thu, 22 Dec 2016 07:14:33 +0000 (07:14 +0000)]
[PM] Remove now-dead extern template and explicit instantiation
declarations.
We're using a custom class here instead of the helper template, these
bits just didn't get deleted when the other bits did get deleted. This
was found by a really nice MSVC warning about explicitly instantiating
a template where some member functions aren't defined and thus can't be
instantiatied.
Chandler Carruth [Thu, 22 Dec 2016 06:59:15 +0000 (06:59 +0000)]
[PM] Introduce a reasonable port of the main per-module pass pipeline
from the old pass manager in the new one.
I'm not trying to support (initially) the numerous options that are
currently available to customize the pass pipeline. If we end up really
wanting them, we can add them later, but I suspect many are no longer
interesting. The simplicity of omitting them will help a lot as we sort
out what the pipeline should look like in the new PM.
I've also documented to the best of my ability *why* each pass or group
of passes is used so that reading the pipeline is more helpful. In many
cases I think we have some questionable choices of ordering and I've
left FIXME comments in place so we know what to come back and revisit
going forward. But for now, I've left it as similar to the current
pipeline as I could.
Lastly, I've had to comment out several places where passes are not
ported to the new pass manager or where the loop pass infrastructure is
not yet ready. I did at least fix a few bugs in the loop pass
infrastructure uncovered by running the full pipeline, but I didn't want
to go too far in this patch -- I'll come back and re-enable these as the
infrastructure comes online. But I'd like to keep the comments in place
because I don't want to lose track of which passes need to be enabled
and where they go.
One thing that seemed like a significant API improvement was to require
that we don't build pipelines for O0. It seems to have no real benefit.
I've also switched back to returning pass managers by value as at this
API layer it feels much more natural to me for composition. But if
others disagree, I'm happy to go back to an output parameter.
I'm not 100% happy with the testing strategy currently, but it seems at
least OK. I may come back and try to refactor or otherwise improve this
in subsequent patches but I wanted to at least get a good starting point
in place.
Adrian Prantl [Thu, 22 Dec 2016 06:10:41 +0000 (06:10 +0000)]
Fix an assertion in DwarfExpression when emitting fragments in vector registers
When DwarfExpression is emitting a fragment that is located in a
register and that fragment is smaller than the register, and the
register must be composed from sub-registers (are you still with me?)
the last DW_OP_piece operation must not be larger than the size of the
fragment itself, since the last piece of the fragment could be smaller
than the last subregister that is being emitted.
Matt Arsenault [Thu, 22 Dec 2016 04:39:45 +0000 (04:39 +0000)]
DAG: Add helper for testing constant values
There are helpers for testing for constant or constant build_vector,
and for splat ConstantFP vectors, but not for a constantfp or
non-splat ConstantFP vector.