with an initial number of elements, instead of DenseMap, which has
zero initial elements, in order to avoid the copying of elements
when the size changes and to avoid allocating space every time
LegalizeTypes is run. This patch will not affect the memory footprint,
because DenseMap will increase the element size to 64
when the first element is added.
Patch by Wan Xiaofei.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@173448 91177308-0d34-0410-b5e6-96231b3b80d8
Maintain separate per-node and per-tree book-keeping.
Track all instructions above a DAG node including nested subtrees.
Seperately track instructions within a subtree.
Record subtree parents.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@173426 91177308-0d34-0410-b5e6-96231b3b80d8
Allow the strategy to select SchedDFS. Allow the results of SchedDFS
to affect initialization of the scheduler state.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@173425 91177308-0d34-0410-b5e6-96231b3b80d8
This is mostly refactoring, along with adding an instruction count
within the subtrees and ensuring we only look at data edges.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@173420 91177308-0d34-0410-b5e6-96231b3b80d8
For sanity, create a root when NumDataSuccs >= 4. Splitting large
subtrees will no longer be detrimental after my next checkin to handle
nested tree. A magic number of 4 is fine because single subtrees
seldom rejoin more than this. It makes subtrees easier to visualize
and heuristics more sane.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@173399 91177308-0d34-0410-b5e6-96231b3b80d8
Allow schedulers to order DAG edges by critical path. This makes
DFS-based heuristics more stable and effective.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@173317 91177308-0d34-0410-b5e6-96231b3b80d8
The requirements of the strong heuristic are:
* A Protector is required for functions which contain an array, regardless of
type or length.
* A Protector is required for functions which contain a structure/union which
contains an array, regardless of type or length. Note, there is no limit to
the depth of nesting.
* A protector is required when the address of a local variable (i.e., stack
based variable) is exposed. (E.g., such as through a local whose address is
taken as part of the RHS of an assignment or a local whose address is taken as
part of a function argument.)
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@173231 91177308-0d34-0410-b5e6-96231b3b80d8
SSPStrong applies a heuristic to insert stack protectors in these situations:
* A Protector is required for functions which contain an array, regardless of
type or length.
* A Protector is required for functions which contain a structure/union which
contains an array, regardless of type or length. Note, there is no limit to
the depth of nesting.
* A protector is required when the address of a local variable (i.e., stack
based variable) is exposed. (E.g., such as through a local whose address is
taken as part of the RHS of an assignment or a local whose address is taken as
part of a function argument.)
This patch implements the SSPString attribute to be equivalent to
SSPRequired. This will change in a subsequent patch.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@173230 91177308-0d34-0410-b5e6-96231b3b80d8
Previously we tried to infer it from the bit width size, with an added
IsIEEE argument for the PPC/IEEE 128-bit case, which had a default
value. This default value allowed bugs to creep in, where it was
inappropriate.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@173138 91177308-0d34-0410-b5e6-96231b3b80d8
A SparseMultiSet adds multiset behavior to SparseSet, while retaining SparseSet's desirable properties. Essentially, SparseMultiSet provides multiset behavior by storing its dense data in doubly linked lists that are inlined into the dense vector. This allows it to provide good data locality as well as vector-like constant-time clear() and fast constant time find(), insert(), and erase(). It also allows SparseMultiSet to have a builtin recycler rather than keeping SparseSet's behavior of always swapping upon removal, which allows it to preserve more iterators. It's often a better alternative to a SparseSet of a growable container or vector-of-vector.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@173064 91177308-0d34-0410-b5e6-96231b3b80d8
The optimization handles esoteric cases but adds a lot of complexity both to the X86 backend and to other backends.
This optimization disables an important canonicalization of chains of SEXT nodes and makes SEXT and ZEXT asymmetrical.
Disabling the canonicalization of consecutive SEXT nodes into a single node disables other DAG optimizations that assume
that there is only one SEXT node. The AVX mask optimizations is one example. Additionally this optimization does not update the cost model.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@172968 91177308-0d34-0410-b5e6-96231b3b80d8
Further encapsulation of the Attribute object. Don't allow direct access to the
Attribute object as an aggregate.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@172853 91177308-0d34-0410-b5e6-96231b3b80d8
changing both the string of the dwo_name to be correct and the type of
the statement list.
Testcases all around.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@172699 91177308-0d34-0410-b5e6-96231b3b80d8
Move the early if-conversion pass into this group.
ILP optimizations usually need to find the right balance between
register pressure and ILP using the MachineTraceMetrics analysis to
identify critical paths and estimate other costs. Such passes should run
together so they can share dominator tree and loop info analyses.
Besides if-conversion, future passes to run here here could include
expression height reduction and ARM's MLxExpansion pass.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@172687 91177308-0d34-0410-b5e6-96231b3b80d8
of a class. Emit static data member declarations and definitions
through correctly.
Part of PR14471.
Patch by Paul Robinson!
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@172590 91177308-0d34-0410-b5e6-96231b3b80d8
using the DW_FORM_GNU_addr_index and a separate .debug_addr section which
stays in the executable and is fully linked.
Sneak in two other small changes:
a) Print out the debug_str_offsets.dwo section.
b) Change form we're expecting the entries in the debug_str_offsets.dwo
section to take from ULEB128 to U32.
Add tests for all of this in the fission-cu.ll test.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@172578 91177308-0d34-0410-b5e6-96231b3b80d8
The included test case is derived from one of the GCC compatibility tests.
The problem arises after the selection DAG has been converted to type-legalized
form. The combiner first sees a 64-bit load that can be converted into a
pre-increment form. The original load feeds into a SRL that isolates the
upper 32 bits of the loaded doubleword. This looks like an opportunity for
DAGCombiner::ReduceLoadWidth() to replace the 64-bit load with a 32-bit load.
However, this transformation is not valid, as the replacement load is not
a pre-increment load. The pre-increment load produces an extra result,
which feeds a subsequent add instruction. The replacement load only has
one result value, and this value is propagated to all uses of the pre-
increment load, including the add. Because the add is looking for the
second result value as its operand, it ends up attempting to add a constant
to a token chain, resulting in a crash.
So the patch simply disables this transformation for any load with more than
two result values.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@172480 91177308-0d34-0410-b5e6-96231b3b80d8
When tryEvict() is looking for a cheaper register in the allocation
order, skip the tail of too expensive registers when possible.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@172281 91177308-0d34-0410-b5e6-96231b3b80d8
Remember the minimum cost of the registers in an allocation order and
the number of registers at the end of the allocation order that have the
same cost per use.
This information can be used to limit the search space for
RAGreedy::tryEvict() when looking for a cheaper register.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@172280 91177308-0d34-0410-b5e6-96231b3b80d8
This fixes some of the cycles between libCodeGen and libSelectionDAG. It's still
a complete mess but as long as the edges consist of virtual call it doesn't
cause breakage. BasicTTI did static calls and thus broke some build
configurations.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@172246 91177308-0d34-0410-b5e6-96231b3b80d8
the target if it supports the different CAST types. We didn't do this
on X86 because of the different register sizes and types, but on ARM
this makes sense.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@172245 91177308-0d34-0410-b5e6-96231b3b80d8
- recognize string "{memory}" in the MI generation
- mark as mayload/maystore when there's a memory clobber constraint.
PR14859.
Patch by Krzysztof Parzyszek
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@172228 91177308-0d34-0410-b5e6-96231b3b80d8
When calling hasProperty() on an instruction inside a bundle, it should
always behave as if IgnoreBundle was passed, and just return properties
for the current instruction.
Only attempt to aggregate bundle properties whan asked about the bundle
header.
The assertion fires on existing ARM test cases without this fix.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@172082 91177308-0d34-0410-b5e6-96231b3b80d8
requirement when creating stack objects in MachineFrameInfo.
Add CreateStackObjectWithMinAlign to throw error when the minimal alignment
can't be achieved and to clamp the alignment when the preferred alignment
can't be achieved. Same is true for CreateVariableSizedObject.
Will not emit error in CreateSpillStackObject or CreateStackObject.
As long as callers of CreateStackObject do not assume the object will be
aligned at the requested alignment, we should not have miscompile since
later optimizations which look at the object's alignment will have the correct
information.
rdar://12713765
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@172027 91177308-0d34-0410-b5e6-96231b3b80d8
It cahced XOR's operands before calling visitXOR() but failed to update the
operands when visitXOR changed the XOR node.
rdar://12968664
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@171999 91177308-0d34-0410-b5e6-96231b3b80d8
The bundle flags are used by MachineBasicBlock::print(), they don't need
to clutter up individual MachineInstrs.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@171986 91177308-0d34-0410-b5e6-96231b3b80d8
It is possible to build MI bundles that don't begin with a BUNDLE
header. Add support for such bundles, counting all instructions inside
the bundle.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@171985 91177308-0d34-0410-b5e6-96231b3b80d8
fp128 is almost but not quite completely illegal as a type on AArch64. As a
result it needs to have a register class (for argument passing mainly), but all
operations need to be lowered to runtime calls. Currently there's no way for
targets to do this (without duplicating code), as the relevant functions are
hidden in SelectionDAG. This patch changes that.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@171971 91177308-0d34-0410-b5e6-96231b3b80d8
This was an experimental option, but needs to be defined
per-target. e.g. PPC A2 needs to aggressively hide latency.
I converted some in-order scheduling tests to A2. Hal is working on
more test cases.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@171946 91177308-0d34-0410-b5e6-96231b3b80d8
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.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@171842 91177308-0d34-0410-b5e6-96231b3b80d8
proposal. This leaves the strings in the skeleton die as strp,
but in all dwo files they're accessed now via DW_FORM_GNU_str_index.
Add support for dumping these sections and modify the fission-cu.ll
testcase to have the correct strings and form. Fix a small bug
in the fixed form sizes routine that involved out of array accesses
for the table and add a FIXME in the extractFast routine to fix
this up.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@171779 91177308-0d34-0410-b5e6-96231b3b80d8
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.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@171739 91177308-0d34-0410-b5e6-96231b3b80d8
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. =]
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@171735 91177308-0d34-0410-b5e6-96231b3b80d8
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)
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@171698 91177308-0d34-0410-b5e6-96231b3b80d8
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.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@171681 91177308-0d34-0410-b5e6-96231b3b80d8
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.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@171625 91177308-0d34-0410-b5e6-96231b3b80d8
This change essentially reverts r87069 which came without a test case. It
causes no regressions in the GDB 7.5 test suite & fixes 25 xfails (commit
to the test suite to follow). If anyone can present a test case that
demonstrates why this check is necessary I'd be happy to account for it in one
way or another.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@171609 91177308-0d34-0410-b5e6-96231b3b80d8
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().
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@171599 91177308-0d34-0410-b5e6-96231b3b80d8
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.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@171598 91177308-0d34-0410-b5e6-96231b3b80d8
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.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@171597 91177308-0d34-0410-b5e6-96231b3b80d8
types and a FIXME for what we should be doing. Should solve the
immediacy of PR12069 where our debug info is crashing another
tool.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@171536 91177308-0d34-0410-b5e6-96231b3b80d8
Most IMPLICIT_DEF instructions are removed by the ProcessImplicitDefs
pass, and a few are reinserted by PHIElimination when a PHI argument is
<undef>.
RegisterCoalescer was assuming that all IMPLICIT_DEF live ranges look
like those created by PHIElimination, and that their live range never
leaves the basic block.
The PR14732 test case does tricks with PHI nodes that causes a longer
IMPLICIT_DEF live range to appear. This happens very rarely, but
RegisterCoalescer should be able to handle it.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@171435 91177308-0d34-0410-b5e6-96231b3b80d8
DAGCombiner::reduceBuildVecConvertToConvertBuildVec() was making two
mistakes:
1. It was checking the legality of scalar INT_TO_FP nodes and then generating
vector nodes.
2. It was passing the result value type to
TargetLoweringInfo::getOperationAction() when it should have been
passing the value type of the first operand.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@171420 91177308-0d34-0410-b5e6-96231b3b80d8
into their new header subdirectory: include/llvm/IR. This matches the
directory structure of lib, and begins to correct a long standing point
of file layout clutter in LLVM.
There are still more header files to move here, but I wanted to handle
them in separate commits to make tracking what files make sense at each
layer easier.
The only really questionable files here are the target intrinsic
tablegen files. But that's a battle I'd rather not fight today.
I've updated both CMake and Makefile build systems (I think, and my
tests think, but I may have missed something).
I've also re-sorted the includes throughout the project. I'll be
committing updates to Clang, DragonEgg, and Polly momentarily.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@171366 91177308-0d34-0410-b5e6-96231b3b80d8
utils/sort_includes.py script.
Most of these are updating the new R600 target and fixing up a few
regressions that have creeped in since the last time I sorted the
includes.
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The later API is nicer than the former, and is correct regarding wrap-around offsets (if anyone cares).
There are a few more places left with duplicated code, which I'll remove soon.
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directly.
This is in preparation for removing the use of the 'Attribute' class as a
collection of attributes. That will shift to the AttributeSet class instead.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@171253 91177308-0d34-0410-b5e6-96231b3b80d8
These are now generally used for all diagnostics from the backend, not just
for inline assembly, so this drops the "InlineAsm" from the names. No
functional change. (I've left aliases for the old names but only for long
enough to let me switch over clang to use the new ones.)
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When the backend is used from clang, it should produce proper diagnostics
instead of just printing messages to errs(). Other clients may also want to
register their own error handlers with the LLVMContext, and the same handler
should work for warnings in the same way as the existing emitError methods.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@171041 91177308-0d34-0410-b5e6-96231b3b80d8
Back when this exception was added, it was skipping a lot more code, but
now it just looks like a premature optimization.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@170989 91177308-0d34-0410-b5e6-96231b3b80d8
The representation of the Operands array is going to change soon so it
can be allocated from a BumpPtrAllocator.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@170988 91177308-0d34-0410-b5e6-96231b3b80d8
Instructions that are inserted in a basic block can still be decorated
with addOperand(MO).
Make the two-argument addOperand() function contain the actual
implementation. This function will now always have a valid MF reference
that it can use for memory allocation.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@170798 91177308-0d34-0410-b5e6-96231b3b80d8
This function is often used to decorate dangling instructions, so a
context reference is required to allocate memory for the operands.
Also add a corresponding MachineInstrBuilder method.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@170797 91177308-0d34-0410-b5e6-96231b3b80d8
This is supposed to be a mechanical change with no functional effects.
InstrEmitter can generate all types of MachineOperands which revealed
that MachineInstrBuilder was missing a few methods, added by this patch.
Besides providing a context pointer to MI::addOperand(),
MachineInstrBuilder seems like a better fit for this code.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@170712 91177308-0d34-0410-b5e6-96231b3b80d8
Use the version that also takes an MF reference instead.
It would technically be possible to extract an MF reference from the MI
as MI->getParent()->getParent(), but that would not work for MIs that
are not inserted into any basic block.
Given the reasonably small number of places this constructor was used at
all, I preferred the compile time check to a run time assertion.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@170588 91177308-0d34-0410-b5e6-96231b3b80d8
bitwidth op back to the original size. If we reduce ANDs then this can cause
an endless loop. This patch changes the ZEXT to ANY_EXTEND if the demanded bits
are equal or smaller than the size of the reduced operation.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@170505 91177308-0d34-0410-b5e6-96231b3b80d8
The bundle_iterator::operator++ function now doesn't need to dig out the
basic block and check against end(). It can use the isBundledWithSucc()
flag to find the last bundled instruction safely.
Similarly, MachineInstr::isBundled() no longer needs to look at
iterators etc. It only has to look at flags.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@170473 91177308-0d34-0410-b5e6-96231b3b80d8
Now that the bundle flag aware APIs are all in place, it is possible to
continuously verify the flag consistency.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@170465 91177308-0d34-0410-b5e6-96231b3b80d8
The new bidirectional bundle flags are redundant, so inadvertent bundle
tearing can be detected in the machine code verifier.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@170463 91177308-0d34-0410-b5e6-96231b3b80d8
The bundle-related MI flags need to be kept in sync with the neighboring
instructions. Don't allow the bulk flag-setting setFlags() function to
change them.
Also don't copy MI flags when cloning an instruction. The clone's bundle
flags will be set when it is explicitly inserted into a bundle.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@170459 91177308-0d34-0410-b5e6-96231b3b80d8
Remove the instr_iterator versions of the splice() functions. It doesn't
seem useful to be able to splice sequences of instructions that don't
consist of full bundles.
The normal splice functions that take MBB::iterator arguments are not
changed, and they can move whole bundles around without any problems.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@170456 91177308-0d34-0410-b5e6-96231b3b80d8
The normal insert() function takes an MBB::iterator position, and
inserts a stand-alone MachineInstr as before.
The insert() function that takes an MBB::instr_iterator position can
insert instructions inside a bundle, and will now update the bundle
flags correctly when that happens.
When the insert position is between two bundles, it is unclear whether
the instruction should be appended to the previous bundle, prepended to
the next bundle, or stand on its own. The MBB::insert() function doesn't
bundle the instruction in that case, use the MIBundleBuilder class for
that.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@170437 91177308-0d34-0410-b5e6-96231b3b80d8
A register can be associated with several distinct register classes.
For example, on PPC, the floating point registers are each associated with
both F4RC (which holds f32) and F8RC (which holds f64). As a result, this code
would fail when provided with a floating point register and an f64 operand
because it would happen to find the register in the F4RC class first and
return that. From the F4RC class, SDAG would extract f32 as the register
type and then assert because of the invalid implied conversion between
the f64 value and the f32 register.
Instead, search all register classes. If a register class containing the
the requested register has the requested type, then return that register
class. Otherwise, as before, return the first register class found that
contains the requested register.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@170436 91177308-0d34-0410-b5e6-96231b3b80d8
Most code is oblivious to bundles and uses the MBB::iterator which only
visits whole bundles. MBB::erase() operates on whole bundles at a time
as before.
MBB::remove() now refuses to remove bundled instructions. It is not safe
to remove all instructions in a bundle without deleting them since there
is no way of returning pointers to all the removed instructions.
MBB::remove_instr() and MBB::erase_instr() will now update bundle flags
correctly, lifting individual instructions out of bundles while leaving
the remaining bundle intact.
The MachineInstr convenience functions are updated so
eraseFromParent() erases a whole bundle as before
eraseFromBundle() erases a single instruction, leaving the rest of its bundle.
removeFromParent() refuses to operate on bundled instructions, and
removeFromBundle() lifts a single instruction out of its bundle.
These functions will no longer accidentally split or coalesce bundles -
bundle flags are updated to preserve the existing bundling, and explicit
bundleWith* / unbundleFrom* functions should be used to change the
instruction bundling.
This API update is still a work in progress. I am going to update APIs
first so they maintain bundle flags automatically when possible. Then
I'll add stricter verification of the bundle flags.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@170384 91177308-0d34-0410-b5e6-96231b3b80d8
TargetLowering::getRegClassFor).
Some isSimple() guards were missing, or getSimpleVT() were hoisted too
far, resulting in asserts on valid LLVM assembly input.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@170336 91177308-0d34-0410-b5e6-96231b3b80d8
Mips16 is really a processor decoding mode (ala thumb 1) and in the same
program, mips16 and mips32 functions can exist and can call each other.
If a jal type instruction encounters an address with the lower bit set, then
the processor switches to mips16 mode (if it is not already in it). If the
lower bit is not set, then it switches to mips32 mode.
The linker knows which functions are mips16 and which are mips32.
When relocation is performed on code labels, this lower order bit is
set if the code label is a mips16 code label.
In general this works just fine, however when creating exception handling
tables and dwarf, there are cases where you don't want this lower order
bit added in.
This has been traditionally distinguished in gas assembly source by using a
different syntax for the label.
lab1: ; this will cause the lower order bit to be added
lab2=. ; this will not cause the lower order bit to be added
In some cases, it does not matter because in dwarf and debug tables
the difference of two labels is used and in that case the lower order
bits subtract each other out.
To fix this, I have added to mcstreamer the notion of a debuglabel.
The default is for label and debug label to be the same. So calling
EmitLabel and EmitDebugLabel produce the same result.
For various reasons, there is only one set of labels that needs to be
modified for the mips exceptions to work. These are the "$eh_func_beginXXX"
labels.
Mips overrides the debug label suffix from ":" to "=." .
This initial patch fixes exceptions. More changes most likely
will be needed to DwarfCFException to make all of this work
for actual debugging. These changes will be to emit debug labels in some
places where a simple label is emitted now.
Some historical discussion on this from gcc can be found at:
http://gcc.gnu.org/ml/gcc-patches/2008-08/msg00623.htmlhttp://gcc.gnu.org/ml/gcc-patches/2008-11/msg01273.html
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@170279 91177308-0d34-0410-b5e6-96231b3b80d8
The new API is higher level than just manipulating the bundle flags
directly, and the setIsInsideBundle() function will disappear soon.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@170159 91177308-0d34-0410-b5e6-96231b3b80d8
Accordingly, add helper funtions getSimpleValueType (in parallel to
getValueType) in SDValue, SDNode, and TargetLowering.
This is the first, in a series of patches.
This is the second attempt. In the first attempt (r169837), a few
getSimpleVT() were hoisted too far, detected by bootstrap failures.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@170104 91177308-0d34-0410-b5e6-96231b3b80d8
load / store pair. It's not legal to use a wider load than the size of
the remaining bytes if it's the first pair of load / store.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@170018 91177308-0d34-0410-b5e6-96231b3b80d8
mention the inline memcpy / memset expansion code is a mess?
This patch split the ZeroOrLdSrc argument into two: IsMemset and ZeroMemset.
The first indicates whether it is expanding a memset or a memcpy / memmove.
The later is whether the memset is a memset of zero. It's totally possible
(likely even) that targets may want to do different things for memcpy and
memset of zero.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@169959 91177308-0d34-0410-b5e6-96231b3b80d8
Also added more comments to explain why it is generally ok to return true.
- Rename getOptimalMemOpType argument IsZeroVal to ZeroOrLdSrc. It's meant to
be true for loaded source (memcpy) or zero constants (memset). The poor name
choice is probably some kind of legacy issue.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@169954 91177308-0d34-0410-b5e6-96231b3b80d8
ScalarTargetTransformInfo::getIntImmCost() instead. "Legal" is a poorly defined
term for something like integer immediate materialization. It is always possible
to materialize an integer immediate. Whether to use it for memcpy expansion is
more a "cost" conceern.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@169929 91177308-0d34-0410-b5e6-96231b3b80d8
Accordingly, add helper funtions getSimpleValueType (in parallel to
getValueType) in SDValue, SDNode, and TargetLowering.
This is the first, in a series of patches.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@169837 91177308-0d34-0410-b5e6-96231b3b80d8
try to reduce the width of this load, and would end up transforming:
(truncate (lshr (sextload i48 <ptr> as i64), 32) to i32)
to
(truncate (zextload i32 <ptr+4> as i64) to i32)
We lost the sext attached to the load while building the narrower i32
load, and replaced it with a zext because lshr always zext's the
results. Instead, bail out of this combine when there is a conflict
between a sextload and a zext narrowing. The rest of the DAG combiner
still optimize the code down to the proper single instruction:
movswl 6(...),%eax
Which is exactly what we wanted. Previously we read past the end *and*
missed the sign extension:
movl 6(...), %eax
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@169802 91177308-0d34-0410-b5e6-96231b3b80d8
This shouldn't affect codegen for -O0 compiles as tail call markers are not
emitted in unoptimized compiles. Testing with the external/internal nightly
test suite reveals no change in compile time performance. Testing with -O1,
-O2 and -O3 with fast-isel enabled did not cause any compile-time or
execution-time failures. All tests were performed on my x86 machine.
I'll monitor our arm testers to ensure no regressions occur there.
In an upcoming clang patch I will be marking the objc_autoreleaseReturnValue
and objc_retainAutoreleaseReturnValue as tail calls unconditionally. While
it's theoretically true that this is just an optimization, it's an
optimization that we very much want to happen even at -O0, or else ARC
applications become substantially harder to debug.
Part of rdar://12553082
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@169796 91177308-0d34-0410-b5e6-96231b3b80d8
controls each of the abbreviation sets (only a single one at the
moment) and computes offsets separately as well for each set
of DIEs.
No real function change, ordering of abbreviations for the skeleton
CU changed but only because we're computing in a separate order. Fix
the testcase not to care.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@169793 91177308-0d34-0410-b5e6-96231b3b80d8
1. Teach it to use overlapping unaligned load / store to copy / set the trailing
bytes. e.g. On 86, use two pairs of movups / movaps for 17 - 31 byte copies.
2. Use f64 for memcpy / memset on targets where i64 is not legal but f64 is. e.g.
x86 and ARM.
3. When memcpy from a constant string, do *not* replace the load with a constant
if it's not possible to materialize an integer immediate with a single
instruction (required a new target hook: TLI.isIntImmLegal()).
4. Use unaligned load / stores more aggressively if target hooks indicates they
are "fast".
5. Update ARM target hooks to use unaligned load / stores. e.g. vld1.8 / vst1.8.
Also increase the threshold to something reasonable (8 for memset, 4 pairs
for memcpy).
This significantly improves Dhrystone, up to 50% on ARM iOS devices.
rdar://12760078
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@169791 91177308-0d34-0410-b5e6-96231b3b80d8
InitSections is called before the MCContext is initialized it could cause
duplicate temporary symbols to be emitted later (after context initialization
resets the temporary label counter).
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@169785 91177308-0d34-0410-b5e6-96231b3b80d8
misched used GetUnderlyingObject in order to break false load/store
dependencies, and the -enable-aa-sched-mi feature similarly relied on
GetUnderlyingObject in order to ensure it is safe to use the aliasing analysis.
Unfortunately, GetUnderlyingObject does not recurse through phi nodes, and so
(especially due to LSR) all of these mechanisms failed for
induction-variable-dependent loads and stores inside loops.
This change replaces uses of GetUnderlyingObject with GetUnderlyingObjects
(which will recurse through phi and select instructions) in misched.
Andy reviewed, tested and simplified this patch; Thanks!
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@169744 91177308-0d34-0410-b5e6-96231b3b80d8
This is still a work in progress. The purpose is to make bundling and
unbundling operations explicit, and to catch errors where bundles are
broken or created inadvertently.
The old IsInsideBundle flag is replaced by two MI flags: BundledPred
which has the same meaning as IsInsideBundle, and BundledSucc which is
set on instructions that are bundled with a successor. Having two flags
provdes redundancy to detect when a bundle is inadvertently torn by a
splice() or insert(), and it makes it possible to write bundle iterators
that don't need to peek at adjacent instructions.
The new flags can't be manipulated directly (once setIsInsideBundle is
gone). Instead there are MI functions to make and break bundle bonds.
The setIsInsideBundle function will be removed in a future commit. It
should be replaced by bundleWithPred().
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@169583 91177308-0d34-0410-b5e6-96231b3b80d8
original change description:
change MCContext to work on the doInitialization/doFinalization model
reviewed by Evan Cheng <evan.cheng@apple.com>
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@169553 91177308-0d34-0410-b5e6-96231b3b80d8
understand target implementation of any_extend / extload, just generate
zero_extend in place of any_extend for liveouts when the target knows the
zero_extend will be implicit (e.g. ARM ldrb / ldrh) or folded (e.g. x86 movz).
rdar://12771555
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@169536 91177308-0d34-0410-b5e6-96231b3b80d8
check if loads that happen in between stores alias with the first store in the
chain, only with the second store onwards.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@169516 91177308-0d34-0410-b5e6-96231b3b80d8
Some languages, e.g. Ada and Pascal, allow you to specify that the array bounds
are different from the default (1 in these cases). If we have a lower bound
that's non-default, then we emit the lower bound. We also calculate the correct
upper bound in those cases.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@169484 91177308-0d34-0410-b5e6-96231b3b80d8
This is much simpler to reason about, more efficient, and
fixes some corner cases involving implicit super-register defs.
Fixed rdar://12797931.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@169425 91177308-0d34-0410-b5e6-96231b3b80d8
A MachineInstr can only ever be constructed by CreateMachineInstr() and
CloneMachineInstr(), and those factories don't use the removed
constructors.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@169395 91177308-0d34-0410-b5e6-96231b3b80d8
- fixed ordering of calls to doFinalization to be the reverse of the pass run order due to potential dependencies
- fixed machine module info to operate in the doInitialization/doFinalization model, also fixes some FIXMEs
reviewed by Evan Cheng <evan.cheng@apple.com>
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@169391 91177308-0d34-0410-b5e6-96231b3b80d8
The count attribute is more accurate with regards to the size of an array. It
also obviates the upper bound attribute in the subrange. We can also better
handle an unbound array by setting the count to -1 instead of the lower bound to
1 and upper bound to 0.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@169312 91177308-0d34-0410-b5e6-96231b3b80d8
This reapplies the fix for PR13303 now with more justification. Based on my
execution of the GDB 7.5 test suite this results in:
expected passes: 16101 -> 20890 (+30%)
unexpected failures: 4826 -> 637 (-77%)
There are 23 checks that used to pass and now fail. They are all in
gdb.reverse. Investigating a few looks like they were accidentally passing
due to extra breakpoints being set by this bug. They're generally due to the
difference in end location between gcc and clang, the test suite is trying to
set breakpoints on the closing '}' that clang doesn't associate with any
instructions.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@169304 91177308-0d34-0410-b5e6-96231b3b80d8
missed in the first pass because the script didn't yet handle include
guards.
Note that the script is now able to handle all of these headers without
manual edits. =]
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@169224 91177308-0d34-0410-b5e6-96231b3b80d8
The count field is necessary because there isn't a difference between the 'lo'
and 'hi' attributes for a one-element array and a zero-element array. When the
count is '0', we know that this is a zero-element array. When it's >=1, then
it's a normal constant sized array. When it's -1, then the array is unbounded.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@169218 91177308-0d34-0410-b5e6-96231b3b80d8
the alignment is clamped to TargetFrameLowering.getStackAlignment if the target
does not support stack realignment or the option "realign-stack" is off.
This will cause miscompile if the address is treated as aligned and add is
replaced with or in DAGCombine.
Added a bool StackRealignable to TargetFrameLowering to check whether stack
realignment is implemented for the target. Also added a bool RealignOption
to MachineFrameInfo to check whether the option "realign-stack" is on.
rdar://12713765
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@169197 91177308-0d34-0410-b5e6-96231b3b80d8
Now that there can be multiple hint registers from targets, it doesn't
make sense to have a function that returns 'the' preferred register.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@169190 91177308-0d34-0410-b5e6-96231b3b80d8
Targets can provide multiple hints now, so getRegAllocPref() doesn't
make sense any longer because it only returns one preferred register.
Replace it with getSimpleHint() in the remaining heuristics. This
function only
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@169188 91177308-0d34-0410-b5e6-96231b3b80d8
No functional change for this commit. The follow-up patch will add more stuff to
these functions.
rdar://12713765
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@169186 91177308-0d34-0410-b5e6-96231b3b80d8
Virtual registers with a known preferred register are prioritized by
RAGreedy. This function makes the condition explicit without depending
on getRegAllocPref().
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@169179 91177308-0d34-0410-b5e6-96231b3b80d8
This simplifies the hinting code quite a bit while making the targets
easier to write at the same time.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@169173 91177308-0d34-0410-b5e6-96231b3b80d8
The TargetRegisterInfo::getRegAllocationHints() function is going to
replace the existing mechanisms for providing target-dependent hints to
the register allocator: ResolveRegAllocHint() and
getRawAllocationOrder().
The new hook is more flexible because it allows the target to provide
multiple preferred candidate registers for each virtual register, and it
is easier to use because targets are not required to return a reference
to a constant array like getRawAllocationOrder().
An optional VirtRegMap argument can be used to provide target-dependent
hints that depend on the provisional assignments of other virtual
registers.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@169154 91177308-0d34-0410-b5e6-96231b3b80d8
Sooooo many of these had incorrect or strange main module includes.
I have manually inspected all of these, and fixed the main module
include to be the nearest plausible thing I could find. If you own or
care about any of these source files, I encourage you to take some time
and check that these edits were sensible. I can't have broken anything
(I strictly added headers, and reordered them, never removed), but they
may not be the headers you'd really like to identify as containing the
API being implemented.
Many forward declarations and missing includes were added to a header
files to allow them to parse cleanly when included first. The main
module rule does in fact have its merits. =]
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@169131 91177308-0d34-0410-b5e6-96231b3b80d8
The TwoAddressInstructionPass takes the machine code out of SSA form by
expanding REG_SEQUENCE instructions into copies. It is no longer
necessary to rewrite the registers used by a REG_SEQUENCE instruction
because the new coalescer algorithm can do it now.
REG_SEQUENCE is just converted to a sequence of sub-register copies now.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@169067 91177308-0d34-0410-b5e6-96231b3b80d8
part of the compile unit CU and start separating out information into
the various sections that will be pulled out later.
WIP.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@169061 91177308-0d34-0410-b5e6-96231b3b80d8
MachineCopyPropagation doesn't understand super-register liveness well
enough to be able to remove implicit defs of super-registers.
This fixes a problem in ARM/2012-01-26-CopyPropKills.ll that is exposed
by an future TwoAddressInstructionPass change. The KILL instructions are
removed before the machine code is emitted.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@169060 91177308-0d34-0410-b5e6-96231b3b80d8
The original patch removed a bunch of code that the SjLjEHPrepare pass placed
into the entry block if all of the landing pads were removed during the
CodeGenPrepare class. The more natural way of doing things is to run the CGP
*before* we run the SjLjEHPrepare pass.
Make it so!
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This was found by MSVC10's STL debug mode on a test from the test suite. Sadly
std::is_heap isn't standard so there is no way to assert this without writing
our own heap verify, which looks like overkill to me.
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If we need to split the operand of a VSELECT, it must be the mask operand. We
split the entire VSELECT operand with EXTRACT_SUBVECTOR.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@168883 91177308-0d34-0410-b5e6-96231b3b80d8
For some targets, it is desirable to prefer scalarizing <N x i1> instead of promoting to a larger legal type, such as <N x i32>.
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This could cause miscompilations in targets where sub-register
composition is not always idempotent (ARM).
<rdar://problem/12758887>
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@168837 91177308-0d34-0410-b5e6-96231b3b80d8
