arguably better than forward iterators for this use case, they are confusing and
there are some implementation problems with reverse iterators and MI bundles.
llvm-svn: 175393
MachineBasicBlock::SplitCriticalEdge. Since this is an iterator rather than
an instr_iterator, the isBundled() check only passes if getFirstTerminator()
returned end() and the garbage memory happens to lean that way.
Multiple successors can be present without any terminator instructions in the
case of exception handling with a fallthrough.
llvm-svn: 175383
terminators that actually have register uses when splitting critical edges.
This commit also introduces a method repairIntervalsInRange() on LiveIntervals,
which allows for repairing LiveIntervals in a small range after an arbitrary
target hook modifies, inserts, and removes instructions. It's pretty limited
right now, but I hope to extend it to support all of the things that are done
by the convertToThreeAddress() target hooks.
llvm-svn: 175382
If the frame pointer is omitted, and any stack changes occur in the inline
assembly, e.g.: "pusha", then any C local variable or C argument references
will be incorrect.
I pass no judgement on anyone who would do such a thing. ;)
rdar://13218191
llvm-svn: 175334
If two functions require different features (e.g., `-mno-sse' vs. `-msse') then
we want to honor that, especially during LTO. We can do that by resetting the
subtarget's features depending upon the 'target-feature' attribute.
llvm-svn: 175314
- add sincos to runtime library if target triple environment is GNU
- added canCombineSinCosLibcall() which checks that sincos is in the RTL and
if the environment is GNU then unsafe fpmath is enabled (required to
preserve errno)
- extended sincos-opt lit test
Reviewed by: Hal Finkel
llvm-svn: 175283
of the copy is a subregister def. The current code assumes that it can do a full
def of the destination register, but it is not checking that the def operand is
read-undef. It also doesn't clear the subregister index of the destination in
the new instruction to reflect the full subregister def.
These issues were found running 'make check' with my next commit that enables
rematerialization in more cases.
llvm-svn: 175122
RegisterCoalescer used to depend on LiveDebugVariable. LDV removes DBG_VALUEs
without emitting them at the end.
We fix this by removing LDV from RegisterCoalescer. Also add an assertion to
make sure we call emitDebugValues if DBG_VALUEs are removed at
runOnMachineFunction.
rdar://problem/13183203
Reviewed by Andy & Jakob
llvm-svn: 175023
DAGCombiner::ReduceLoadWidth was converting (trunc i32 (shl i64 v, 32))
into (shl i32 v, 32) into undef. To prevent this, check the shift count
against the final result size.
Patch by: Kevin Schoedel
Reviewed by: Nadav Rotem
llvm-svn: 174972
live ranges should always be extended, and the only successor that should be
considered for extension of other ranges is the target of the split edge.
llvm-svn: 174935
Sorry for the lack of a test case. I tried writing one for i386 as i know selects are illegal on this target, but they are actually considered legal by isel and expanded later.
I can't see any targets to trigger this, but checking for the legality of a node before forming it is general goodness.
llvm-svn: 174934
This is currently a bit hairier than it needs to be, since depending on where the
split block resides the end ListEntry of the split block may be the end ListEntry
of the original block or a new entry. Some changes to the SlotIndexes updating
should make it possible to eliminate the two cases here.
This also isn't as optimized as it could be. In the future Liveinterval should
probably get a flag that indicates whether the LiveInterval is within a single
basic block. We could ignore all such intervals when splitting an edge.
llvm-svn: 174870
This reverts my commit 171047. Now that I've removed my misguided attempt to
support backend warnings, these diagnostics are only about inline assembly.
It would take quite a bit more work to generalize them properly, so I'm
just reverting this.
llvm-svn: 174860
function is successfully handled by fast-isel. That's because function
arguments are *always* handled by SDISel. Introduce FastLowerArguments to
allow each target to provide hook to handle formal argument lowering.
As a proof-of-concept, add ARMFastIsel::FastLowerArguments to handle
functions with 4 or fewer scalar integer (i8, i16, or i32) arguments. It
completely eliminates the need for SDISel for trivial functions.
rdar://13163905
llvm-svn: 174855
support for updating SlotIndexes to MachineBasicBlock::SplitCriticalEdge(). This
calls renumberIndexes() every time; it should be improved to only renumber
locally.
llvm-svn: 174851
present, it currently verifies them with the MachineVerifier, and this passed
all of the test cases in 'make check' (when accounting for existing verifier
errors). There were some assertion failures in the two-address pass, but they
also happened on code without phis and look like they are caused by different
kill flags from LiveIntervals.
The only part that doesn't work is the critical edge splitting heuristic,
because there isn't currently an efficient way to update LiveIntervals after
splitting an edge. I'll probably start by implementing the slow fallback and
test that it works before tackling the fast path for single-block ranges. The
existing code that updates LiveVariables is fairly slow as it is.
There isn't a command-line option for enabling this; instead, just edit
PHIElimination.cpp to require LiveIntervals.
llvm-svn: 174831
This uses a liveness algorithm that does not depend on data from the
LiveVariables analysis, it is the first step towards removing
LiveVariables completely.
llvm-svn: 174774
This reverts r171041. This was a nice idea that didn't work out well.
Clang warnings need to be associated with warning groups so that they can
be selectively disabled, promoted to errors, etc. This simplistic patch didn't
allow for that. Enhancing it to provide some way for the backend to specify
a front-end warning type seems like overkill for the few uses of this, at
least for now.
llvm-svn: 174748
Previously, even when a pre-increment load or store was generated,
we often needed to keep a copy of the original base register for use
with other offsets. If all of these offsets are constants (including
the offset which was combined into the addressing mode), then this is
clearly unnecessary. This change adjusts these other offsets to use the
new incremented address.
llvm-svn: 174746
Aside from the question of whether we report a warning or an error when we
can't satisfy a requested stack object alignment, the current implementation
of this is not good. We're not providing any source location in the diagnostics
and the current warning is not connected to any warning group so you can't
control it. We could improve the source location somewhat, but we can do a
much better job if this check is implemented in the front-end, so let's do that
instead. <rdar://problem/13127907>
llvm-svn: 174741
Adds a function to target transform info to query for the cost of address
computation. The cost model analysis pass now also queries this interface.
The code in LoopVectorize adds the cost of address computation as part of the
memory instruction cost calculation. Only there, we know whether the instruction
will be scalarized or not.
Increase the penality for inserting in to D registers on swift. This becomes
necessary because we now always assume that address computation has a cost and
three is a closer value to the architecture.
radar://13097204
llvm-svn: 174713
Failure: undefined symbol 'Lline_table_start0'.
Root-cause: we use a symbol subtraction to calculate at_stmt_list, but
the line table entries are not dumped in the assembly.
Fix: use zero instead of a symbol subtraction for Compile Unit 0.
llvm-svn: 174479
base point of a load, and the overall alignment of the load. This caused infinite loops in DAG combine with the
original application of this patch.
ORIGINAL COMMIT LOG:
When the target-independent DAGCombiner inferred a higher alignment for a load,
it would replace the load with one with the higher alignment. However, it did
not place the new load in the worklist, which prevented later DAG combines in
the same phase (for example, target-specific combines) from ever seeing it.
This patch corrects that oversight, and updates some tests whose output changed
due to slightly different DAGCombine outputs.
llvm-svn: 174431
All targets are now adding return value registers as implicit uses on
return instructions, and there is no longer a need for the live out
lists.
llvm-svn: 174417
it would replace the load with one with the higher alignment. However, it did
not place the new load in the worklist, which prevented later DAG combines in
the same phase (for example, target-specific combines) from ever seeing it.
This patch corrects that oversight, and updates some tests whose output changed
due to slightly different DAGCombine outputs.
llvm-svn: 174343
Per discussion in rdar://13127907, we should emit a hard error only if
people write code where the requested alignment is larger than achievable
and assumes the low bits are zeros. A warning should be good enough when
we are not sure if the source code assumes the low bits are zeros.
rdar://13127907
llvm-svn: 174336
This required disabling a PowerPC optimization that did the following:
input:
x = BUILD_VECTOR <i32 16, i32 16, i32 16, i32 16>
lowered to:
tmp = BUILD_VECTOR <i32 8, i32 8, i32 8, i32 8>
x = ADD tmp, tmp
The add now gets folded immediately and we're back at the BUILD_VECTOR we
started from. I don't see a way to fix this currently so I left it disabled
for now.
Fix some trivially foldable X86 tests too.
llvm-svn: 174325
We used to create children DIEs for a scope, then check whether ScopeDIE is
null. If ScopeDIE is null, the children DIEs will be dangling. Other DIEs can
link to those dangling DIEs, which are not emitted at all, causing dwarf error.
The current testing case is 4k lines, from MultiSource/BenchMark/McCat/09-vor.
rdar://problem/13071959
llvm-svn: 174084
conditions are met:
1. They share the same operand and are in the same BB.
2. Both outputs are used.
3. The target has a native instruction that maps to ISD::FSINCOS node or
the target provides a sincos library call.
Implemented the generic optimization in sdisel and enabled it for
Mac OSX. Also added an additional optimization for x86_64 Mac OSX by
using an alternative entry point __sincos_stret which returns the two
results in xmm0 / xmm1.
rdar://13087969
PR13204
llvm-svn: 173755
The common code in the post-RA scheduler to break anti-dependencies on the
critical path contained a flaw. In the reported case, an anti-dependency
between the overlapping registers %X4 and %R4 exists:
%X29<def> = OR8 %X4, %X4
%R4<def>, %X3<def,dead,tied3> = LBZU 1, %X3<kill,tied1>
The unpatched code breaks the dependency by replacing %R4 and its uses
with %R3, the first register on the available list. However, %R3 and
%X3 overlap, so this creates two overlapping definitions on the same
instruction.
The fix is straightforward, preventing selection of a register that
overlaps any other defined register on the same instruction.
The test case is reduced from the bug report, and verifies that we no
longer produce "lbzu 3, 1(3)" when breaking this anti-dependency.
llvm-svn: 173706
Fix that by adding a cast to the shift expander. This came up with vector shifts
on sse-less X86 CPUs.
<2 x i64> = shl <2 x i64> <2 x i64>
-> i64,i64 = shl i64 i64; shl i64 i64
-> i32,i32,i32,i32 = shl_parts i32 i32 i64; shl_parts i32 i32 i64
Now we cast the last two i64s to the right type. Fixes the crash in PR14668.
llvm-svn: 173615
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.
llvm-svn: 173448
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.
llvm-svn: 173426
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.
llvm-svn: 173399
Craig Topper