sequence - target independent framework
When the DAGcombiner selects instruction sequences
it could increase the critical path or resource len.
For example, on arm64 there are multiply-accumulate instructions (madd,
msub). If e.g. the equivalent multiply-add sequence is not on the
crictial path it makes sense to select it instead of the combined,
single accumulate instruction (madd/msub). The reason is that the
conversion from add+mul to the madd could lengthen the critical path
by the latency of the multiply.
But the DAGCombiner would always combine and select the madd/msub
instruction.
This patch uses machine trace metrics to estimate critical path length
and resource length of an original instruction sequence vs a combined
instruction sequence and picks the faster code based on its estimates.
This patch only commits the target independent framework that evaluates
and selects code sequences. The machine instruction combiner is turned
off for all targets and expected to evolve over time by gradually
handling DAGCombiner pattern in the target specific code.
This framework lays the groundwork for fixing
rdar://16319955
llvm-svn: 214666
This makes EmitWindowsUnwindTables a virtual function and lowers the
implementation of the function to the X86WinCOFFStreamer. This method is a
target specific operation. This enables making the behaviour target dependent
by isolating it entirely to the target specific streamer.
llvm-svn: 214664
The frame information stored in this structure is driven by the requirements for
Windows NT unwinding rather than Windows 64 specifically. As a result, this
type can be shared across multiple architectures (ARM, AXP, MIPS, PPC, SH).
Rename this class in preparation for adding support for supporting unwinding
information for Windows on ARM.
Take the opportunity to constify the members as everything except the
ChainedParent is read-only. This required some adjustment to the label
handling.
llvm-svn: 214663
`shuffleUseLists()` is only used in `verify-uselistorder`, so move it
there to avoid bloating other executables. As a drive-by, update some
of the header docs.
This is part of PR5680.
llvm-svn: 214592
This updates the instrumentation based profiling format so that when
we have multiple functions with the same name (but different function
hashes) we keep all of them instead of rejecting the later ones.
There are a number of scenarios where this can come up where it's more
useful to keep multiple function profiles:
* Name collisions in unrelated libraries that are profiled together.
* Multiple "main" functions from multiple tools built against a common
library.
* Combining profiles from different build configurations (ie, asserts
and no-asserts)
The profile format now stores the number of counters between the hash
and the counts themselves, so that multiple sets of counts can be
stored. Since this is backwards incompatible, I've bumped the format
version and added some trivial logic to skip this when reading the old
format.
llvm-svn: 214585
variables (for example, by-value struct arguments passed in registers, or
large integer values split across several smaller registers).
On the IR level, this adds a new type of complex address operation OpPiece
to DIVariable that describes size and offset of a variable fragment.
On the DWARF emitter level, all pieces describing the same variable are
collected, sorted and emitted as DWARF expressions using the DW_OP_piece
and DW_OP_bit_piece operators.
http://reviews.llvm.org/D3373
rdar://problem/15928306
What this patch doesn't do / Future work:
- This patch only adds the backend machinery to make this work, patches
that change SROA and SelectionDAG's type legalizer to actually create
such debug info will follow. (http://reviews.llvm.org/D2680)
- Making the DIVariable complex expressions into an argument of dbg.value
will reduce the memory footprint of the debug metadata.
- The sorting/uniquing of pieces should be moved into DebugLocEntry,
to facilitate the merging of multi-piece entries.
llvm-svn: 214576
Although unlinked `BasicBlock`s can be created, there's currently no way
to insert them into `Function`s after the fact. In particular,
`moveAfter()` and `moveBefore()` require that the basic block is already
linked.
Extract the logic for initially linking a `BasicBlock` out of the
constructor and into a member function that can be used for lazy
insertion.
- Asserts that the basic block is currently unlinked.
- Matches the logic of the constructor.
- Changed the constructor to use it since the logic matches.
This is needed in a follow-up commit for PR5680.
llvm-svn: 214563
so that we can use it to get the old-style JIT out of the subtarget.
This code should be removed when the old-style JIT is removed
(imminently).
llvm-svn: 214560
`BlockAddress`es are interesting in that they can reference basic blocks
from *outside* the block's function. Since basic blocks are not global
values, this presents particular challenges for lazy parsing.
One corner case was found in PR11677 and fixed in r147425. In that
case, a global variable references a block address. It's necessary to
load the relevant function to resolve the forward reference before doing
anything with the module.
By inspection, I found (and have fixed here) two other cases:
- An instruction from one function references a block address from
another function, and only the first function is lazily loaded.
I fixed this the same way as PR11677: by eagerly loading the
referenced function.
- A function whose block address is taken is dematerialized, leaving
invalid references to it.
I fixed this by refusing to dematerialize functions whose block
addresses are taken (if you have to load it, you can't unload it).
llvm-svn: 214559
If INTRINSIC_W_CHAIN and INTRINSIC_VOID are MemIntrinsicSDNodes, and a
MemIntrinsicSDNode is a MemSDNode, then INTRINSIC_W_CHAIN and INTRINSIC_VOID
must be MemSDNodes too.
Noticed by inspection.
llvm-svn: 214452
Currently when DAGCombine converts loads feeding a switch into a switch of
addresses feeding a load the new load inherits the isInvariant flag of the left
side. This is incorrect since invariant loads can be reordered in cases where it
is illegal to reoarder normal loads.
This patch adds an isInvariant parameter to getExtLoad() and updates all call
sites to pass in the data if they have it or false if they don't. It also
changes the DAGCombine to use that data to make the right decision when
creating the new load.
llvm-svn: 214449
MSVC [1] thinks `UseListShuffleVector` needs a copy constructor, but I
don't. Let's see if being explicit about `UseListOrder` is convincing.
[1]: http://lab.llvm.org:8011/builders/lld-x86_64-win7/builds/11664/steps/build_Lld/logs/stdio
Here's the failure:
C:/lld-x86_64_win7/lld-x86_64-win7/llvm.src/include\llvm/IR/UseListOrder.h(92): error C2248: 'llvm::UseListShuffleVector::operator =' : cannot access private member declared in class 'llvm::UseListShuffleVector' (C:\lld-x86_64_win7\lld-x86_64-win7\llvm.src\lib\Bitcode\Writer\ValueEnumerator.cpp) [C:\lld-x86_64_win7\lld-x86_64-win7\llvm.obj\lib\Bitcode\Writer\LLVMBitWriter.vcxproj]
C:/lld-x86_64_win7/lld-x86_64-win7/llvm.src/include\llvm/IR/UseListOrder.h(56) : see declaration of 'llvm::UseListShuffleVector::operator ='
C:/lld-x86_64_win7/lld-x86_64-win7/llvm.src/include\llvm/IR/UseListOrder.h(32) : see declaration of 'llvm::UseListShuffleVector'
This diagnostic occurred in the compiler generated function 'llvm::UseListOrder &llvm::UseListOrder::operator =(const llvm::UseListOrder &)'
llvm-svn: 214224
Remove the copy constructor added in r214178 to appease MSVC17 since it
shouldn't be called at all. My guess is that explicitly deleting it
will make the compiler happy. To round out the operations I've also
deleted copy assignment and added move assignment. Otherwise no
functionality change.
llvm-svn: 214213
This will let users in other libraries know which error occurred. In particular,
it will be possible to check if the parsing failed or if the file is not
bitcode.
llvm-svn: 214209
Per feedback on r214111, we are going to use null to represent unspecified
parameter. If the type array is {null}, it means a function that returns void;
If the type array is {null, null}, it means a variadic function that returns
void. In summary if we have more than one element in the type array and the last
element is null, it is a variadic function.
rdar://17628609
llvm-svn: 214189
Since we're storing lots of these, save two-pointers per vector with a
custom type rather than using the relatively heavy `SmallVector`.
Part of PR5680.
llvm-svn: 214135
DITypeArray is an array of DITypeRef, at its creation, we will create
DITypeRef (i.e use the identifier if the type node has an identifier).
This is the last patch to unique the type array of a subroutine type.
rdar://17628609
llvm-svn: 214132
Predict and serialize use-list order in bitcode. This makes the option
`-preserve-bc-use-list-order` work *most* of the time, but this is still
experimental.
- Builds a full value-table up front in the writer, sets up a list of
use-list orders to write out, and discards the table. This is a
simpler first step than determining the order from the various
overlapping IDs of values on-the-fly.
- The shuffles stored in the use-list order list have an unnecessarily
large memory footprint.
- `blockaddress` expressions cause functions to be materialized
out-of-order. For now I've ignored this problem, so use-list orders
will be wrong for constants used by functions that have block
addresses taken. There are a couple of ways to fix this, but I
don't have a concrete plan yet.
- When materializing functions lazily, the use-lists for constants
will not be correct. This use case is out of scope: what should the
use-list order be, if it's incomplete?
This is part of PR5680.
llvm-svn: 214125
Typedef DIArray to DITypedArray<DIDescriptor>. Also typedef DITypeArray as
DITypedArray<DITypeRef>.
This is the third of a series of patches to handle type uniqueing of the
type array for a subroutine type.
This commit should have no functionality change.
llvm-svn: 214115
This is the second of a series of patches to handle type uniqueing of the
type array for a subroutine type.
For vector and array types, getElements returns the array of subranges, so it
is a better name than getTypeArray. Even for class, struct and enum types,
getElements returns the members, which can be subprograms.
setArrays can set up to two arrays, the second is the templates.
This commit should have no functionality change.
llvm-svn: 214112
This is the first of a series of patches to handle type uniqueing of the
type array for a subroutine type.
This commit makes sure unspecified_parameter is a DIType to enable converting
the type array for a subroutine type to an array of DITypes.
This commit should have no functionality change. With this commit, we may
change unspecified type to be a DITrivialType instead of a DIType.
llvm-svn: 214111
Rename to allowsMisalignedMemoryAccess.
On R600, 8 and 16 byte accesses are mostly OK with 4-byte alignment,
and don't need to be split into multiple accesses. Vector loads with
an alignment of the element type are not uncommon in OpenCL code.
llvm-svn: 214055
checking whether the ArrayRef is equal to an explicit list of arguments.
This is particularly easy to implement even without variadic templates
because ArrayRef happens to be homogeneously typed. As a consequence we
can use a "clever" wrapper type and default arguments to capture in
a single method many arguments as well as *how many* arguments the user
specified.
Thanks to Dave Blaikie for helping me pull together this little helper.
Suggestions for how to improve or generalize it are of course welcome.
I'll be using it immediately in my follow-up patch. =D
llvm-svn: 214041
over each node in the worklist prior to combining.
This allows the combiner to produce new nodes which need to go back
through legalization. This is particularly useful when generating
operands to target specific nodes in a post-legalize DAG combine where
the operands are significantly easier to express as pre-legalized
operations. My immediate use case will be PSHUFB formation where we need
to build a constant shuffle mask with a build_vector node.
This also refactors the relevant functionality in the legalizer to
support this, and updates relevant tests. I've spoken to the R600 folks
and these changes look like improvements to them. The avx512 change
needs to be investigated, I suspect there is a disagreement between the
legalizer and the DAG combiner there, but it seems a minor issue so
leaving it to be re-evaluated after this patch.
Differential Revision: http://reviews.llvm.org/D4564
llvm-svn: 214020
