method because getContents().size() already covers it. So computeFragmentSize
can use the generic MCEncodedFragment interface when querying both Data and
Relaxable fragments for contents sizes.
No change in functionality
llvm-svn: 171903
Current targets don't have more than 256 relocations so they don't hit this
limit, but ELF64 actually allows more than 8 bits for a relocation type. These
were being truncated on AArch64.
llvm-svn: 171845
one file where it is called as a static function. Nuke the declaration
and the definition in lib/CodeGen, along with the include of
SelectionDAG.h from this file.
There is no dependency edge from lib/CodeGen to
lib/CodeGen/SelectionDAG, so it isn't valid for a routine in lib/CodeGen
to reference the DAG. There is a dependency from
lib/CodeGen/SelectionDAG on lib/CodeGen. This breaks one violation of
this layering.
llvm-svn: 171842
This is necessary not only for representing empty ranges, but for handling
multibyte characters in the input. (If the end pointer in a range refers to
a multibyte character, should it point to the beginning or the end of the
character in a char array?) Some of the code in the asm parsers was already
assuming this anyway.
llvm-svn: 171765
turning a code like this:
if (foo)
free(foo)
into that:
free(foo)
Move a call to free from basic block FB into FB's predecessor, P,
when the path from P to FB is taken only if the argument of free is
not equal to NULL.
Some restrictions apply on P and FB to be sure that this code motion
is profitable. Namely:
1. FB must have only one predecessor P.
2. FB must contain only the call to free plus an unconditional
branch to S.
3. P's successors are FB and S.
Because of 1., we will not increase the code size when moving the call
to free from FB to P.
Because of 2., FB will be empty after the move.
Because of 2. and 3., P's branch instruction becomes useless, so as FB
(simplifycfg will do the job).
llvm-svn: 171762
peculiar headers under include/llvm.
This struct still doesn't make a lot of sense, but it makes more sense
down in TargetLowering than it did before.
llvm-svn: 171739
TargetTransformInfo rather than TargetLowering, removing one of the
primary instances of the layering violation of Transforms depending
directly on Target.
This is a really big deal because LSR used to be a "special" pass that
could only be tested fully using llc and by looking at the full output
of it. It also couldn't run with any other loop passes because it had to
be created by the backend. No longer is this true. LSR is now just
a normal pass and we should probably lift the creation of LSR out of
lib/CodeGen/Passes.cpp and into the PassManagerBuilder. =] I've not done
this, or updated all of the tests to use opt and a triple, because
I suspect someone more familiar with LSR would do a better job. This
change should be essentially without functional impact for normal
compilations, and only change behvaior of targetless compilations.
The conversion required changing all of the LSR code to refer to the TTI
interfaces, which fortunately are very similar to TargetLowering's
interfaces. However, it also allowed us to *always* expect to have some
implementation around. I've pushed that simplification through the pass,
and leveraged it to simplify code somewhat. It required some test
updates for one of two things: either we used to skip some checks
altogether but now we get the default "no" answer for them, or we used
to have no information about the target and now we do have some.
I've also started the process of removing AddrMode, as the TTI interface
doesn't use it any longer. In some cases this simplifies code, and in
others it adds some complexity, but I think it's not a bad tradeoff even
there. Subsequent patches will try to clean this up even further and use
other (more appropriate) abstractions.
Yet again, almost all of the formatting changes brought to you by
clang-format. =]
llvm-svn: 171735
This c'tor takes the AttributeSet class as the parameter. It will eventually
grab the attributes from the specified index and create a new attribute builder
with those attributes.
llvm-svn: 171712
This works fine with GDB for member variable pointers, but GDB's support for
member function pointers seems to be quite unrelated to
DW_TAG_ptr_to_member_type. (see GDB bug 14998 for details)
llvm-svn: 171698
through as a reference rather than a pointer. There is always *some*
implementation of this available, so this simplifies code by not having
to test for whether it is available or not.
Further, it turns out there were piles of places where SimplifyCFG was
recursing and not passing down either TD or TTI. These are fixed to be
more pedantically consistent even though I don't have any particular
cases where it would matter.
llvm-svn: 171691
a TargetMachine to construct (and thus isn't always available), to an
analysis group that supports layered implementations much like
AliasAnalysis does. This is a pretty massive change, with a few parts
that I was unable to easily separate (sorry), so I'll walk through it.
The first step of this conversion was to make TargetTransformInfo an
analysis group, and to sink the nonce implementations in
ScalarTargetTransformInfo and VectorTargetTranformInfo into
a NoTargetTransformInfo pass. This allows other passes to add a hard
requirement on TTI, and assume they will always get at least on
implementation.
The TargetTransformInfo analysis group leverages the delegation chaining
trick that AliasAnalysis uses, where the base class for the analysis
group delegates to the previous analysis *pass*, allowing all but tho
NoFoo analysis passes to only implement the parts of the interfaces they
support. It also introduces a new trick where each pass in the group
retains a pointer to the top-most pass that has been initialized. This
allows passes to implement one API in terms of another API and benefit
when some other pass above them in the stack has more precise results
for the second API.
The second step of this conversion is to create a pass that implements
the TargetTransformInfo analysis using the target-independent
abstractions in the code generator. This replaces the
ScalarTargetTransformImpl and VectorTargetTransformImpl classes in
lib/Target with a single pass in lib/CodeGen called
BasicTargetTransformInfo. This class actually provides most of the TTI
functionality, basing it upon the TargetLowering abstraction and other
information in the target independent code generator.
The third step of the conversion adds support to all TargetMachines to
register custom analysis passes. This allows building those passes with
access to TargetLowering or other target-specific classes, and it also
allows each target to customize the set of analysis passes desired in
the pass manager. The baseline LLVMTargetMachine implements this
interface to add the BasicTTI pass to the pass manager, and all of the
tools that want to support target-aware TTI passes call this routine on
whatever target machine they end up with to add the appropriate passes.
The fourth step of the conversion created target-specific TTI analysis
passes for the X86 and ARM backends. These passes contain the custom
logic that was previously in their extensions of the
ScalarTargetTransformInfo and VectorTargetTransformInfo interfaces.
I separated them into their own file, as now all of the interface bits
are private and they just expose a function to create the pass itself.
Then I extended these target machines to set up a custom set of analysis
passes, first adding BasicTTI as a fallback, and then adding their
customized TTI implementations.
The fourth step required logic that was shared between the target
independent layer and the specific targets to move to a different
interface, as they no longer derive from each other. As a consequence,
a helper functions were added to TargetLowering representing the common
logic needed both in the target implementation and the codegen
implementation of the TTI pass. While technically this is the only
change that could have been committed separately, it would have been
a nightmare to extract.
The final step of the conversion was just to delete all the old
boilerplate. This got rid of the ScalarTargetTransformInfo and
VectorTargetTransformInfo classes, all of the support in all of the
targets for producing instances of them, and all of the support in the
tools for manually constructing a pass based around them.
Now that TTI is a relatively normal analysis group, two things become
straightforward. First, we can sink it into lib/Analysis which is a more
natural layer for it to live. Second, clients of this interface can
depend on it *always* being available which will simplify their code and
behavior. These (and other) simplifications will follow in subsequent
commits, this one is clearly big enough.
Finally, I'm very aware that much of the comments and documentation
needs to be updated. As soon as I had this working, and plausibly well
commented, I wanted to get it committed and in front of the build bots.
I'll be doing a few passes over documentation later if it sticks.
Commits to update DragonEgg and Clang will be made presently.
llvm-svn: 171681
pass into the SelectionDAG itself rather than snooping on the
implementation of that pass as exposed by the TargetMachine. This
removes the last direct client of the ScalarTargetTransformInfo class
outside of the TTI pass implementation.
llvm-svn: 171625
interfaces which could be extracted from it, and must be provided on
construction, to a chained analysis group.
The end goal here is that TTI works much like AA -- there is a baseline
"no-op" and target independent pass which is in the group, and each
target can expose a target-specific pass in the group. These passes will
naturally chain allowing each target-specific pass to delegate to the
generic pass as needed.
In particular, this will allow a much simpler interface for passes that
would like to use TTI -- they can have a hard dependency on TTI and it
will just be satisfied by the stub implementation when that is all that
is available.
This patch is a WIP however. In particular, the "stub" pass is actually
the one and only pass, and everything there is implemented by delegating
to the target-provided interfaces. As a consequence the tools still have
to explicitly construct the pass. Switching targets to provide custom
passes and sinking the stub behavior into the NoTTI pass is the next
step.
llvm-svn: 171621
VectorTargetTransformInfo into the TargetTransformInfo pass,
implementing them be delegating back out to the two subobjects.
This is the first step to folding the interfaces together and making
TargetTransformInfo a normal analysis pass (specifically an analysis
group which targets can provide target-specific analysis pass
implementations of).
No callers are migrated here, this just stubs out the interface. Next
step will be to migrate all the callers to directly operate on TTI
instead of STTI or VTTI respectively. That will allow replacing the
machinery for delivering TTI without changing every caller at once.
WIP, I promise all the duplicated interfaces will be removed in the end,
this just decouples the steps of the process.
llvm-svn: 171615
values -- that's not required to fix the bug that was cropping up, and
the values selected made the enumeration's underlying type signed and
introduced some warnings. This fixes the -Werror build.
The underlying issue here was that the DenseMapInfo was casting values
completely outside the range of the underlying storage of the
enumeration to the enumeration's type. GCC went and "optimized" that
into infloops and other misbehavior. By providing designated special
values for these keys in the dense map, we ensure they are indeed
representable and that they won't be used for anything else.
It might be better to reuse None for the empty key and have the
tombstone share the value of the sentinel enumerator, but honestly
having 2 extra enumerators seemed not to matter and this seems a bit
simpler. I'll let Bill shuffle this around (or ask me to shuffle it
around) if he prefers it to look a different way.
I also made the switch a bit more clear (and produce a better assert)
that the enumerators are *never* going to show up and are errors if they
do.
llvm-svn: 171614
With DenseMapInfo<Enum>, it is miscompiled on g++-4.4.
static inline Enum getEmptyKey() { return Enum(<arbitrary int/unsigned value>); }
isEauql(getEmptyKey(), ...)
The compiler mis-assumes the return value is not aliased to Enum.
llvm-svn: 171600
The series of patches leading up to this one makes llc -O0 run 8% faster.
When deallocating a MachineFunction, there is no need to visit all
MachineInstr and MachineOperand objects to deallocate them. All their
memory come from a BumpPtrAllocator that is about to be purged, and they
have empty destructors anyway.
This only applies when deallocating the MachineFunction.
DeleteMachineInstr() should still be used to recycle MI memory during
the codegen passes.
Remove the LeakDetector support for MachineInstr. I've never seen it
used before, and now it definitely doesn't work. With this patch, leaked
MachineInstrs would be much less of a problem since all of their memory
will be reclaimed by ~MachineFunction().
llvm-svn: 171599
Instead of an std::vector<MachineOperand>, use MachineOperand arrays
from an ArrayRecycler living in MachineFunction.
This has several advantages:
- MachineInstr now has a trivial destructor, making it possible to
delete them in batches when destroying MachineFunction. This will be
enabled in a later patch.
- Bypassing malloc() and free() can be faster, depending on the system
library.
- MachineInstr objects and their operands are allocated from the same
BumpPtrAllocator, so they will usually be next to each other in
memory, providing better locality of reference.
- Reduce MachineInstr footprint. A std::vector is 24 bytes, the new
operand array representation only uses 8+4+1 bytes in MachineInstr.
- Better control over operand array reallocations. In the old
representation, the use-def chains would be reordered whenever a
std::vector reached its capacity. The new implementation never changes
the use-def chain order.
Note that some decisions in the code generator depend on the use-def
chain orders, so this patch may cause different assembly to be produced
in a few cases.
llvm-svn: 171598
This function works like memmove() for MachineOperands, except it also
updates any use-def chains containing the moved operands.
The use-def chains are updated without affecting the order of operands
in the list. That isn't possible when using the
removeRegOperandFromUseList() and addRegOperandToUseList() functions.
Callers to follow soon.
llvm-svn: 171597
legality of an address mode to not use a struct of four values and
instead to accept them as parameters. I'd love to have named parameters
here as most callers only care about one or two of these, but the
defaults aren't terribly scary to write out.
That said, there is no real impact of this as the passes aren't yet
using STTI for this and are still relying upon TargetLowering.
llvm-svn: 171595
next to its only user. This helper relies on TargetLowering information
that shouldn't be generally used throughout the Transfoms library, and
so it made little sense as a generic utility.
This also consolidates the file where we need to remove the remaining
uses of TargetLowering in favor of the IR-layer abstract interface in
TargetTransformInfo.
llvm-svn: 171590
Eric Christopher