This is a mechanical change of dynamic_cast<> to dyn_cast<>. A number of
these uses are actually more like isa<> or cast<>, and will be changed
to the semanticaly appropriate one in a future patch.
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are in fact identity operations. We detect these and kill their
partitions so that even splitting is unaffected by them. This is
particularly important because Clang relies on emitting identity memcpy
operations for struct copies, and these fold away to constants very
often after inlining.
Fixes the last big performance FIXME I have on my plate.
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the rewrite visitor to make the fact that the speculation is completely
independent a bit more clear.
I promise that this is just a cut/paste of the one visitor and adding
the annonymous namespace wrappings. The diff may look completely
preposterous, it does in git for some reason.
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Make sure functions located in user specified text sections (via the
section attribute) are located together with the default text sections.
Otherwise, for large object files, the relocations for call instructions
are more likely to be out of range. This becomes even more likely in the
presence of LTO.
rdar://12402636
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a) frame setup instructions define the prologue
b) we shouldn't change our location mid-stream
Add a test to make sure that the stack adjustment stays within
the prologue.
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- Add 'HwEncoding' for X86 registers and call getEncodingValue() to
retrieve their encoding values.
- This's the first step to adopt new scheme. Furthur revising is onging.
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"Instruction 'foo' has no tokens" errors during llvm-tblgen
-gen-asm-matcher attempts. At this time, the added
tokens are "#comment" style rather than the actual mnemonic. This will
be revisited once the rest of the base asmparser bits get straightened
out for ppc64-elf-linux.
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We conservatively only check the first use to avoid walking long use chains.
This catches the common case of having both a load and a store to a pointer
supplied by a PHI node.
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cpyDest can be mutated in some cases, which would then cause a crash later if
indeed the memory was underaligned. This brought down several buildbots, so
I guess the underaligned case is much more common than I thought!
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Currently, we re-visit allocas when something changes about the way they
might be *split* to allow better scalarization to take place. However,
we weren't handling the case when the *promotion* is what would change
the behavior of SROA. When an address derived from an alloca is stored
into another alloca, we consider the first to have escaped. If the
second is ever promoted to an SSA value, we will suddenly be able to run
the SROA pass on the first alloca.
This patch adds explicit support for this form if iteration. When we
detect a store of a pointer derived from an alloca, we flag the
underlying alloca for reprocessing after promotion. The logic works hard
to only do this when there is definitely going to be promotion and it
might remove impediments to the analysis of the alloca.
Thanks to Nick for the great test case and Benjamin for some sanity
check review.
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was less aligned than the old. In the testcase this results in an overaligned
memset: the memset alignment was correct for the original memory but is too much
for the new memory. Fix this by either increasing the alignment of the new
memory or bailing out if that isn't possible. Should fix the gcc-4.7 self-host
buildbot failure.
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Sorry for this being broken so long. =/
As part of this, switch all of the existing tests to be Little Endian,
which is the behavior I was asserting in them anyways! Add in a new
big-endian test that checks the interesting behavior there.
Another part of this is to tighten the rules abotu when we perform the
full-integer promotion. This logic now rejects cases where there fully
promoted integer is a non-multiple-of-8 bitwidth or cases where the
loads or stores touch bits which are in the allocated space of the
alloca but are not loaded or stored when accessing the integer. Sadly,
these aren't really observable today as the rest of the pass will
already ensure the invariants hold. However, the latter situation is
likely to become a potential concern in the future.
Thanks to Benjamin and Duncan for early review of this patch. I'm still
looking into whether there are further endianness issues, please let me
know if anyone sees BE failures persisting past this.
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macro instruction (li) in the assembler.
We have identified three possible expansions depending on
the size of immediate operand:
1) for 0 ≤ j ≤ 65535.
li d,j =>
ori d,$zero,j
2) for −32768 ≤ j < 0.
li d,j =>
addiu d,$zero,j
3) for any other value of j that is representable as a 32-bit integer.
li d,j =>
lui d,hi16(j)
ori d,d,lo16(j)
All of the above have been implemented in ths patch.
Contributer: Vladimir Medic
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.set option
The patch implements following options
at - lets the assembler use the $at register for macros,
but generates warnings if the source program uses $at
noat - let source programs use $at without issuingwarnings.
noreorder - prevents the assembler from reordering machine
language instructions.
nomacro - causes the assembler to print a warning whenever
an assembler operation generates more than one
machine language instruction.
macro - lets the assembler generate multiple machine instructions
from a single assembler instruction
reorder - lets the assembler reorder machine language
instructions to improve performance
The above variants are parsed and their boolean values set or unset.
The code to actually use them will come later.
Following options are not implemented yet:
nomips16
nomicromips
move
nomove
Contributer: Vladimir Medic
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in the Intel syntax.
The MC layer supports emitting in the Intel syntax, but this would require the
inline assembly MachineInstr to be lowered to an MCInst before emission. This
is potential future work, but for now emitting directly from the MachineInstr
suffices.
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for the number of bytes in a particular instruction
to using
const MCInstrDesc &Desc = MCII.get(TmpInst.getOpcode());
Desc.getSize()
This is necessary with the advent of 16 bit instructions with
mips16 and micromips. It is also puts Mips in compliance with
the other targets for getting instruction size.
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In order to avoid rev-lock with Clang when moving to the new API, also
preserve the current API temporarily and insert a shim to implement the
new API in terms of the old.
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multiple stores with a single load. We create the wide loads and stores (and their chains)
before we remove the scalar loads and stores and fix the DAG chain. We attempted to merge
loads with a different chain. When that happened, the assumption that it is safe to RAUW
broke and a cycle was introduced.
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instruction (for Intel Atom) was not being done by Clang, because
the type context used by Clang is not the default context.
It fixes the problem by getting the global context types for each div/rem
instruction in order to compare them against the types in the BypassTypeMap.
Tests for this will be done as a separate patch to Clang.
Patch by Tyler Nowicki.
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is not profitable in many cases because modern processors perform multiple stores
in parallel and merging stores prior to merging requires extra work. We handle two main cases:
1. Store of multiple consecutive constants:
q->a = 3;
q->4 = 5;
In this case we store a single legal wide integer.
2. Store of multiple consecutive loads:
int a = p->a;
int b = p->b;
q->a = a;
q->b = b;
In this case we load/store either ilegal vector registers or legal wide integer registers.
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Corrects a problem whereby MCSchedModel was not being set up when
the CPU type was auto-detected.
Patch by Andy Zhang.
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a memcpy to reflect that '0' has a different meaning when applied to
a load or store. Now we correctly use underaligned loads and stores for
the test case added.
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necessary during rewriting. As part of this, fix a real think-o here
where we might have left off an alignment specification when the address
is in fact underaligned. I haven't come up with any way to trigger this,
as there is always some other factor that reduces the alignment, but it
certainly might have been an observable bug in some way I can't think
of. This also slightly changes the strategy for placing explicit
alignments on loads and stores to only do so when the alignment does not
match that required by the ABI. This causes a few redundant alignments
to go away from test cases.
I've also added a couple of tests that really push on the alignment that
we end up with on loads and stores. More to come here as I try to fix an
underlying bug I have conjectured and produced test cases for, although
it's not clear if this bug is the one currently hitting dragonegg's
gcc47 bootstrap.
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Enable the pass by default for targets that request it, and change the
-enable-early-ifcvt to the opposite -disable-early-ifcvt.
There are still some x86 regressions when enabling early if-conversion
because of the missing machine models. Disable the pass for x86 until
machine models are added.
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preserves the values of the relocated entries, unlikely remove_if. This
allows walking them and erasing them.
Also flesh out the predicate we are using for this to support the
various constraints actually imposed on a UnaryPredicate -- without this
we can't compose it with std::not1.
Thanks to Sean Silva for the review here and noticing the issue with
std::remove_if.
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X86DAGToDAGISel::PreprocessISelDAG(), isel is moving load inside
callseq_start / callseq_end so it can be folded into a call. This can
create a cycle in the DAG when the call is glued to a copytoreg. We
have been lucky this hasn't caused too many issues because the pre-ra
scheduler has special handling of call sequences. However, it has
caused a crash in a specific tailcall case.
rdar://12393897
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If the code is generated as assembler, this transformation does not occur assuming that it will occur later in the assembler.
This code was originally called from MipsAsmPrinter.cpp and we needed to check for OutStreamer.hasRawTextSupport(). This was not a good place for it and has been moved to MCTargetDesc/MipsMCCodeEmitter.cpp where both direct object and the assembler use it it automagically.
The test cases have been checked in for a number of weeks now.
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scheduled for processing on the worklist eventually gets deleted while
we are processing another alloca, fixing the original test case in
PR13990.
To facilitate this, add a remove_if helper to the SetVector abstraction.
It's not easy to use the standard abstractions for this because of the
specifics of SetVectors types and implementation.
Finally, a nice small test case is included. Thanks to Benjamin for the
fantastic reduced test case here! All I had to do was delete some empty
basic blocks!
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Reserved register live ranges look like a set of dead defs - any uses of
reserved registers are ignored.
Instead of skipping the updating of reserved register operands entirely,
just ignore the use operands and treat the def operands normally.
No test case, handleMove() is not commonly used yet.
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of operand is specific to MS-style inline assembly and should not be generated
when parsing normal assembly.
The purpose of the wildcard operands are to allow the AsmParser to match
multiple instructions (i.e., MCInsts) to a given ms-style asm statement. For
the time being the matcher just returns the first match. This patch only
implements wildcard matches for memory operands. Support for register
wildcards will be added in the near future.
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JoinVals::pruneValues() calls LIS->pruneValue() to avoid conflicts when
overlapping two different values. This produces a set of live range end
points that are used to reconstruct the live range (with SSA update)
after joining the two registers.
When a value is pruned twice, the set of end points was insufficient:
v1 = DEF
v1 = REPLACE1
v1 = REPLACE2
KILL v1
The end point at KILL would only reconstruct the live range from
REPLACE2 to KILL, leaving the range REPLACE1-REPLACE2 dead.
Add REPLACE2 as an end point in this case so the full live range is
reconstructed.
This fixes PR13999.
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We require that the indices into the use lists are stable in order to
build fast lookup tables to locate a particular partition use from an
operand of a PHI or select. This is (obviously in hind sight)
incompatible with erasing elements from the array. Really, we don't want
to erase anyways. It is expensive, and a rare operation. Instead, simply
weaken the contract of the PartitionUse structure to allow null Use
pointers to represent dead uses. Now we can clear out the pointer to
mark things as dead, and all it requires is adding some 'continue'
checks to the various loops.
I'm still reducing a test case for this, as the test case I have is
huge. I think this one I can get a nice test case for though, as it was
much more deterministic.
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This adds 'elf' as a recognized target triple environment value and overrides the default generated object format on Windows platforms if that value is present. This patch also enables MCJIT tests on Windows using the new environment value.
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being separate was that it can grow the use list. As a consequence, we
can't use the iterator-pair interface, we need an index based interface.
Expose such an interface from the AllocaPartitioning, and use it in the
speculator.
This should at least fix a use-after-free bug found by Duncan, and may
fix some of the other crashers.
I don't have a nice deterministic test case yet, but if I get a good
one, I'll add it.
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the add/sub case since in the case of multiplication you also have to check that
the operation in the larger type did not overflow.
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map constraints and MCInst operands to inline asm operands. This replaces the
getMCInstOperandNum() function.
The logic to determine the constraints are not in place, so we still default to
a register constraint (i.e., "r"). Also, we no longer build the MCInst but
rather return just the opcode to get the MCInstrDesc.
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The target backend can support data-in-code load commands even when
the assembler doesn't, or vice-versa. Allow targets to opt-in for
direct-to-object.
PR13973.
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Reduces runtime of i386-large-relocations.s by 10x in Release builds, even more
in Debug+Asserts builds.
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alignment requirements of the new alloca. As one consequence which was
reported as a bug by Duncan, we overaligned memcpy calls to ranges of
allocas after they were rewritten to types with lower alignment
requirements. Other consquences are possible, but I don't have any test
cases for them.
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could probably be factored still further to hoist this logic into
a generic helper, but currently I don't have particularly clean ideas
about how to handle that.
This at least allows us to drop custom load rewriting from the
speculation logic, which in turn allows the existing load rewriting
logic to fire. In theory, this could enable vector promotion or other
tricks after speculation occurs, but I've not dug into such issues. This
is primarily just cleaning up the factoring of the code and the
resulting logic.
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a pair of instructions, one for the used pointer and the second for the
user. This simplifies the representation and also makes it more dense.
This was noticed because of the miscompile in PR13926. In that case, we
were running up against a fundamental "bad idea" in the speculation of
PHI and select instructions: the speculation and rewriting are
interleaved, which requires phi speculation to also perform load
rewriting! This is bad, and causes us to miss opportunities to do (for
example) vector rewriting only exposed after PHI speculation, etc etc.
It also, in the old system, required us to insert *new* load uses into
the current partition's use list, which would then be ignored during
rewriting because we had already extracted an end iterator for the use
list. The appending behavior (and much of the other oddities) stem from
the strange de-duplication strategy in the PartitionUse builder.
Amusingly, all this went without notice for so long because it could
only be triggered by having *different* GEPs into the same partition of
the same alloca, where both different GEPs were operands of a single
PHI, and where the GEP which was not encountered first also had multiple
uses within that same PHI node... Hence the insane steps required to
reproduce.
So, step one in fixing this fundamental bad idea is to make the
PartitionUse actually contain a Use*, and to make the builder do proper
deduplication instead of funky de-duplication. This is enough to remove
the appending behavior, and fix the miscompile in PR13926, but there is
more work to be done here. Subsequent commits will lift the speculation
into its own visitor. It'll be a useful step toward potentially
extracting all of the speculation logic into a generic utility
transform.
The existing PHI test case for repeated operands has been made more
extreme to catch even these issues. This test case, run through the old
pass, will exactly reproduce the miscompile from PR13926. ;] We were so
close here!
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source of false positives due to globals being declared in a header with some
kind of incomplete (small) type, but the actual definition being bigger.
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because moden processos can store multiple values in parallel, and preparing the consecutive store requires
some work. We only handle these cases:
1. Consecutive stores where the values and consecutive loads. For example:
int a = p->a;
int b = p->b;
q->a = a;
q->b = b;
2. Consecutive stores where the values are constants. Foe example:
q->a = 4;
q->b = 5;
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alignment could lose it due to the alloca type moving down to a much
smaller alignment guarantee.
Now SROA will actively compute a proper alignment, factoring the target
data, any explicit alignment, and the offset within the struct. This
will in some cases lower the alignment requirements, but when we lower
them below those of the type, we drop the alignment entirely to give
freedom to the code generator to align it however is convenient.
Thanks to Duncan for the lovely test case that pinned this down. =]
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buildbots. Original commit message:
A DAGCombine optimization for merging consecutive stores. This optimization is not profitable in many cases
because moden processos can store multiple values in parallel, and preparing the consecutive store requires
some work. We only handle these cases:
1. Consecutive stores where the values and consecutive loads. For example:
int a = p->a;
int b = p->b;
q->a = a;
q->b = b;
2. Consecutive stores where the values are constants. Foe example:
q->a = 4;
q->b = 5;
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because moden processos can store multiple values in parallel, and preparing the consecutive store requires
some work. We only handle these cases:
1. Consecutive stores where the values and consecutive loads. For example:
int a = p->a;
int b = p->b;
q->a = a;
q->b = b;
2. Consecutive stores where the values are constants. Foe example:
q->a = 4;
q->b = 5;
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2. As part of this, added assembly format FEXT_RI16_SP_explicit_ins and
moved other lines for FEXT_RI16 formats to be in the right place in the code.
3. Added mayLoad and mayStore assignements for the load/store instructions added and for ones already there that did not have this assignment.
4. Another patch will deal with the problem of load/store byte/halfword to the stack. This is a particular Mips16 problem.
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The new coalescer can turn a full virtual register definition into a
partial redef by merging another value into an unused vector lane.
Make sure to clear the <read-undef> flag on such defs.
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The fix is obvious and the only test case I have is horrible, so I am
not including it. The problem shows up when self-hosting clang on i386
with -new-coalescer enabled.
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If the width is very large it gets truncated from uint64_t to uint32_t when
passed to TD->fitsInLegalInteger. The truncated value can fit in a register.
This manifested in massive memory usage or crashes (PR13946).
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This is a preliminary step towards ELF support; currently ARMFastISel hasn't
been used for ELF object files yet.
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The hasFnAttr method has been replaced by querying the Attributes explicitly. No
intended functionality change.
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If the offset is more than 24-bits, it won't fit in a scattered
relocation offset field, so we fall back to using a non-scattered
relocation.
rdar://12358909
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This opaque class will contain all of the attributes. All attribute queries will
go through this object. This object will also be uniqued in the LLVMContext.
Currently not used, so no implementation change.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@164722 91177308-0d34-0410-b5e6-96231b3b80d8
teach the callgraph logic to not create callgraph edges to intrinsics for invoke
instructions; it already skips this for call instructions. Fixes PR13903.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@164707 91177308-0d34-0410-b5e6-96231b3b80d8
- Put statistics in alphabetical order
- Don't use getZextValue when building TableInt, just use APInts
- Introduce Create{Z,S}ExtOrTrunc in IRBuilder.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@164696 91177308-0d34-0410-b5e6-96231b3b80d8
contrived for these yet, as I spotted them by inspection and the test
cases are a bit more tricky to phrase.
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alignment guarantees attached, re-compute the alignment so that we
consider offsets which impact alignment.
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rewriter in SROA to carry a proper alignment. This involves
interrogating various sources of alignment, etc. This is a more complete
and principled fix to PR13920 as well as related bugs pointed out by Eli
in review and by inspection in the area.
Also by inspection fix the integer and vector promotion paths to create
aligned loads and stores. I still need to work up test cases for
these... Sorry for the delay, they were found purely by inspection.
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tables in bitmaps when they fit in a target-legal register.
This saves some space, and it also allows for building tables that would
otherwise be deemed too sparse.
One interesting case that this hits is example 7 from
http://blog.regehr.org/archives/320. We currently generate good code
for this when lowering the switch to the selection DAG: we build a
bitmask to decide whether to jump to one block or the other. My patch
will result in the same bitmask, but it removes the need for the jump,
as the return value can just be retrieved from the mask.
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For example, under a Linux chroot, /proc/ might not be mounted.
Therefor, we test if this file exist. If it is the case, use it (the current
behavior). Otherwise, we fall back to the detection used by *BSD.
The issue has been reported initially on the Debian bug tracker:
http://bugs.debian.org/674588
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This should really, really fix PR13916. For real this time. The
underlying bug is... a bit more subtle than I had imagined.
The setup is a code pattern that leads to an @llvm.memcpy call with two
equal pointers to an alloca in the source and dest. Now, not any pattern
will do. The alloca needs to be formed just so, and both pointers should
be wrapped in different bitcasts etc. When this precise pattern hits,
a funny sequence of events transpires. First, we correctly detect the
potential for overlap, and correctly optimize the memcpy. The first
time. However, we do simplify the set of users of the alloca, and that
causes us to run the alloca back through the SROA pass in case there are
knock-on simplifications. At this point, a curious thing has happened.
If we happen to have an i8 alloca, we have direct i8 pointer values. So
we don't bother creating a cast, we rewrite the arguments to the memcpy
to dircetly refer to the alloca.
Now, in an unrelated area of the pass, we have clever logic which
ensures that when visiting each User of a particular pointer derived
from an alloca, we only visit that User once, and directly inspect all
of its operands which refer to that particular pointer value. However,
the mechanism used to detect memcpy's with the potential to overlap
relied upon getting visited once per *Use*, not once per *User*. This is
always true *unless* the same exact value is both source and dest. It
turns out that almost nothing actually produces that pattern though.
We can hand craft test cases that more directly test this behavior of
course, and those are included. Also, note that there is a significant
missed optimization here -- we prove in many cases that there is
a non-volatile memcpy call with identical source and dest addresses. We
shouldn't prevent splitting the alloca in that case, and in fact we
should just remove such memcpy calls eagerly. I'll address that in
a subsequent commit.
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scalar-to-vector conversion that we cannot handle. For instance, when an invalid
constraint is used in an inline asm statement.
<rdar://problem/12284092>
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- Instead of embedding 'lock' into each mnemonic of atomic
instructions except 'xchg', we teach X86 assembly printer to output 'lock'
prefix similar to or consistent with code emitter.
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scalar-to-vector conversion that we cannot handle. For instance, when an invalid
constraint is used in an inline asm statement.
<rdar://problem/12284092>
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only a missed optimization opportunity if the store is over-aligned, but a
miscompile if the store's new type has a higher natural alignment than the
memcpy did. Fixes PR13920!
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reason we were getting two of the same alloca is because of a memmove/memcpy
which had the same alloca in both the src and dest. Now we detect that case
directly. This has the same testcase as before, but fixes a clang test
CodeGenObjC/exceptions.m which runs clang -O2.
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Chandler, it's not obvious that it's okay that this alloca gets into the list
twice to begin with. Please review and see whether this is the fix you really
want, but I wanted to get a fix checked in quickly.
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Provide interface in TargetLowering to set or get the minimum number of basic
blocks whereby jump tables are generated for switch statements rather than an
if sequence.
getMinimumJumpTableEntries() defaults to 4.
setMinimumJumpTableEntries() allows target configuration.
This patch changes the default for the Hexagon architecture to 5
as it improves performance on some benchmarks.
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When a BL/BLX references a symbol in the same translation unit that is
out of range, use an external relocation. The linker will use this to
generate a branch island rather than a direct reference, allowing the
relocation to resolve correctly.
rdar://12359919
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to chains or cycles between PHIs and/or selects. Also add a couple of
really nice test cases reduced from Kostya's reports in PR13905 and
PR13906. Both are fixed by this patch.
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Previously it was only be able to detect problems if the pointer was a numerical
value (eg inttoptr i32 1 to i32*), but not if it was an alloca or globa. The
reason was the use of ComputeMaskedBits: imagine you have "alloca i8, align 2",
and ask ComputeMaskedBits what it knows about the bits of the alloca pointer.
It can tell you that the bottom bit is known zero (due to align 2) but it can't
tell you that bit 1 is known one. That's because the address could be an even
multiple of 2 rather than an odd multiple, eg it might be a multiple of 4. Thus
trying to use KnownOne is ineffective in the case of an alloca as it will never
have any bits set. Instead look explicitly for constant offsets from allocas
and globals.
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David (I think), but I would appreciate folks verifying that this fixes
the big crasher.
I'm still working on a reduced test case, but because this was causing
problems I wanted to get the fix checked in quickly.
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Even out-of-line jump tables can be in the code section, so mark them
as data-regions for those targets which support the directives.
rdar://12362871&12362974
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store when handling byval arguments. Thus preventing reordering of the store
with load with post-RA scheduler.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@164553 91177308-0d34-0410-b5e6-96231b3b80d8
integer promotion analogous to vector promotion. When there is an
integer alloca being accessed both as its integer type and as a narrower
integer type, promote the narrower access to "insert" and "extract" the
smaller integer from the larger one, and make the integer alloca
a candidate for promotion.
In the new formulation, we don't care about target legal integer or use
thresholds to control things. Instead, we only perform this promotion to
an integer type which the frontend has already emitted a load or store
for. This bounds the scope and prevents optimization passes from
coalescing larger and larger entities into a single integer.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@164479 91177308-0d34-0410-b5e6-96231b3b80d8
across the uses of the alloca. It's entirely possible for negative
numbers to come up here, and in some rare cases simply doing the 2's
complement arithmetic isn't the correct decision. Notably, we can't zext
the index of the GEP. The definition of GEP is that these offsets are
sign extended or truncated to the size of the pointer, and then wrapping
2's complement arithmetic used.
This patch fixes an issue that comes up with *no* input from the
buildbots or bootstrap afaict. The only place where it manifested,
disturbingly, is Clang's own regression test suite. A reduced and
targeted collection of tests are added to cope with this. Note that I've
tried to pin down the potential cases of overflow, but may have missed
some cases. I've tried to add a few cases to test this, but its hard
because LLVM has quite limited support for >64bit constructs.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@164475 91177308-0d34-0410-b5e6-96231b3b80d8
As before with load instructions, oddities like "asr #32", "rrx" could
be printed incorrectly.
Patch by Chris Lidbury.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@164456 91177308-0d34-0410-b5e6-96231b3b80d8
This patch fixes load/store instructions to handle less common cases
like "asr #32", "rrx" properly throughout the MC layer.
Patch by Chris Lidbury.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@164455 91177308-0d34-0410-b5e6-96231b3b80d8
selects with a constant condition. This resulted in the operands
remaining live through the SROA rewriter. Most of the time, this just
caused some dead allocas to persist and get zapped by later passes, but
in one case found by Joerg, it caused a crash when we tried to *promote*
the alloca despite it having this dead use. We already have the
mechanisms in place to handle this, just wire select up to them.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@164427 91177308-0d34-0410-b5e6-96231b3b80d8
whether or not we want to print out backtrace information. Useful
for libraries that don't need backtrace information on a crash.
rdar://11844710
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care about it being an argument variable so that we can decide
that captured block and lambda vars that don't happen to
be arguments could be an argument pointer.
Add the object pointer for one case onto the subprogram die.
rdar://12001329
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because LiveStackAnalysis was not preserved by VirtRegWriter. This caused
big stack usage regression in some cases.
rdar://12340383
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We rely on it when doing the transforms. This can happen when there is an
indirectbr in the loop.
Fixes PR13892.
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We inserted a placeholder that was never replaced because the function was
already visited. Assert that all placeholders have been resolved when tearing
down the bitcode reader.
Fixes PR13895.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@164369 91177308-0d34-0410-b5e6-96231b3b80d8
- Rewirte most atomic instructions in templates for both better
maintenance and future extensions, such as HLE in TSX.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@164357 91177308-0d34-0410-b5e6-96231b3b80d8
The expression based expansion too often results in IR level optimizations
splitting the intermediate values into separate basic blocks, preventing
the formation of the VBSL instruction as the code author intended. In
particular, LICM would often hoist part of the computation out of a loop.
rdar://11011471
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A PHI can't create interference on its own. If two live ranges interfere
at a PHI, they must also interfere when leaving one of the PHI
predecessors.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@164330 91177308-0d34-0410-b5e6-96231b3b80d8
The old-fashioned many-to-one value mapping doesn't always work when
merging vector lanes. A value can map to multiple different values, and
it can even be necessary to insert new PHIs.
When a value number is defined by a copy from a value number that
required SSa update, include the live range of the copied value number
in the SSA update as well. It is not necessarily a copy of the original
value number any longer.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@164329 91177308-0d34-0410-b5e6-96231b3b80d8
We already have HoistThenElseCodeToIf, this patch implements
SinkThenElseCodeToEnd. When END block has only two predecessors and each
predecessor terminates with unconditional branches, we compare instructions in
IF and ELSE blocks backwards and check whether we can sink the common
instructions down.
rdar://12191395
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- Rewrite/merge pseudo-atomic instruction emitters to address the
following issue:
* Reduce one unnecessary load in spin-loop
previously the spin-loop looks like
thisMBB:
newMBB:
ld t1 = [bitinstr.addr]
op t2 = t1, [bitinstr.val]
not t3 = t2 (if Invert)
mov EAX = t1
lcs dest = [bitinstr.addr], t3 [EAX is implicit]
bz newMBB
fallthrough -->nextMBB
the 'ld' at the beginning of newMBB should be lift out of the loop
as lcs (or CMPXCHG on x86) will load the current memory value into
EAX. This loop is refined as:
thisMBB:
EAX = LOAD [MI.addr]
mainMBB:
t1 = OP [MI.val], EAX
LCMPXCHG [MI.addr], t1, [EAX is implicitly used & defined]
JNE mainMBB
sinkMBB:
* Remove immopc as, so far, all pseudo-atomic instructions has
all-register form only, there is no immedidate operand.
* Remove unnecessary attributes/modifiers in pseudo-atomic instruction
td
* Fix issues in PR13458
- Add comprehensive tests on atomic ops on various data types.
NOTE: Some of them are turned off due to missing functionality.
- Revise tests due to the new spin-loop generated.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@164281 91177308-0d34-0410-b5e6-96231b3b80d8
A common coalescing conflict in vector code is lane insertion:
%dst = FOO
%src = BAR
%dst:ssub0 = COPY %src
The live range of %src interferes with the ssub0 lane of %dst, but that
lane is never read after %src would have clobbered it. That makes it
safe to merge the live ranges and eliminate the COPY:
%dst = FOO
%dst:ssub0 = BAR
This patch teaches the new coalescer to resolve conflicts where dead
vector lanes would be clobbered, at least as long as the clobbered
vector lanes don't escape the basic block.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@164250 91177308-0d34-0410-b5e6-96231b3b80d8
to improve compatibility with GNU as.
Based on a patch by PaX Team.
Fixed assertion failures on non-Darwin and added additional test cases.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@164248 91177308-0d34-0410-b5e6-96231b3b80d8
- Merge the processing of LOAD_ADD with other atomic load-arith
operations
- Separate the logic getting target constant for atomic-load-op and add
an optimization for atomic-load-add on i16 with negative value
- Optimize a minor case for atomic-fetch-add i16 with negative operand. Test
case is revised.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@164243 91177308-0d34-0410-b5e6-96231b3b80d8
lib/Target/PowerPC/PPCISelLowering.{h,cpp}
Rename LowerFormalArguments_Darwin to LowerFormalArguments_Darwin_Or_64SVR4.
Rename LowerFormalArguments_SVR4 to LowerFormalArguments_32SVR4.
Receive small structs right-justified in LowerFormalArguments_Darwin_Or_64SVR4.
Rename LowerCall_Darwin to LowerCall_Darwin_Or_64SVR4.
Rename LowerCall_SVR4 to LowerCall_32SVR4.
Pass small structs right-justified in LowerCall_Darwin_Or_64SVR4.
test/CodeGen/PowerPC/structsinregs.ll
New test.
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two variables where the first variable is returned and the second
ignored.
I don't think this occurs in practice (other passes should have cleaned
up the unused phi node), but it should still be handled correctly.
Also make the logic for determining if we should return early less
sketchy.
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This is a follow-up from r163302, which added a transformation to
SimplifyCFG that turns some switches into loads from lookup tables.
It was pointed out that some targets, such as GPUs and deeply embedded
targets, might not find this appropriate, but SimplifyCFG doesn't have
enough information about the target to decide this.
This patch adds the reverse transformation to CodeGenPrep: it turns
loads from lookup tables back into switches for targets where we do not
build jump tables (assuming these are also the targets where lookup
tables are inappropriate).
Hopefully we will eventually get to have target information in
SimplifyCFG, and then this CodeGenPrep transformation can be removed.
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Two deeply nested if's obscured that the sense of the conditions was
mixed up. Amazingly, TableGen's output is exactly the same even with the
sense of the tests fixed; it seems that all of TableGen's conversions
are symmetric so that the inverted sense was nonetheless correct "by
accident". As such, I couldn't come up with a test case.
If there does in fact exist a non-symmetric conversion in TableGen's
type system, then a test case should be prepared.
Despite the symmetry, both if's are left in place for robustness in the
face of future changes.
Review by Jakob.
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from the dragonegg build bots when we turned on the full version of the
pass. Included a much reduced test case for this pesky bug, despite
bugpoint's uncooperative behavior.
Also, I audited all the similar code I could find and didn't spot any
other cases where this mistake cropped up.
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working on FCA splitting. Instead of refusing to form a common type when
there are uses of a subsection of the alloca as well as a use of the
entire alloca, just skip the subsection uses and continue looking for
a whole-alloca use with a type that we can use.
This produces slightly prettier IR I think, and also fixes the other
failure in the test.
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store this and use it to not emit long nops when the CPU is geode which
doesnt support them.
Fixes PR11212.
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FCAs. This is essential in order to promote allocas that are used in
struct returns by frontends like Clang. The FCA load would block the
rest of the pass from firing, resulting is significant regressions with
the bullet benchmark in the nightly test suite.
Thanks to Duncan for repeated discussions about how best to do this, and
to both him and Benjamin for review.
This appears to have blocked many places where the pass tries to fire,
and so I'm expect somewhat different results with this fix added.
As with the last big patch, I'm including a change to enable the SROA by
default *temporarily*. Ben is going to remove this as soon as the LNT
bots pick up the patch. I'm just trying to get a round of LNT numbers
from the stable machines in the lab.
NOTE: Four clang tests are expected to fail in the brief window where
this is enabled. Sorry for the noise!
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Now where we used to call ReInitMCSubtargetInfo, we actually recompute
the same information as InitMCSubtargetInfo instead of only setting
the feature bits.
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aligned address. Based on patch by David Peixotto.
Also use vld1.64 / vst1.64 with 128-bit alignment to take advantage of alignment
hints. rdar://12090772, rdar://12238782
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Hanlde the case when we split the default edge if the default target has "icmp"
and unconditinal branch.
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Add LIS::pruneValue() and extendToIndices(). These two functions are
used by the register coalescer when merging two live ranges requires
more than a trivial value mapping as supported by LiveInterval::join().
The pruneValue() function can remove the part of a value number that is
going to conflict in join(). Afterwards, extendToIndices can restore the
live range, using any new dominating value numbers and updating the SSA
form.
Use this complex value mapping to support merging a register into a
vector lane that has a conflicting value, but the clobbered lane is
undef.
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These extra operands are not needed by register allocators using
VirtRegRewriter, and RAFast don't need them any longer.
By omitting the <imp-def> operands, it becomes possible for the new
register coalescer to track which lanes are valid and which are undef.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@164073 91177308-0d34-0410-b5e6-96231b3b80d8
partition use lists a bit. No functionality changed.
These visitors are actually visiting a tuple of a Use and an offset into
the alloca. However, we use the InstVisitor to handle the dispatch over
the users, and so the Use and Offset are stored in class member
variables and set just before each call to visit(). This is fairly
awkward and makes the functions a bit harder to read, but its the only
real option we have until InstVisitor can be rewritten to use variadic
templates.
However, this pattern shouldn't be followed on the helper member
functions where there is no interface constraint from the visitor. We
already were passing the instruction as a normal parameter rather than
use the Use to get at it, start passing the offset as well. This will
become more important in subsequent patches as the offset will in some
cases change while visiting a single instruction.
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It had patterns for zext-loading and extending. This commit adds patterns for loading a wide type, performing a bitcast,
and extending. This is an odd pattern, but it is commonly used when writing code with intrinsics.
rdar://11897677
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@163995 91177308-0d34-0410-b5e6-96231b3b80d8
The live range of an SSA value forms a sub-tree of the dominator tree.
That means the live ranges of two values overlap if and only if the def
of one value lies within the live range of the other.
This can be used to simplify the interference checking a bit: Visit each
def in the two registers about to be joined. Check for interference
against the value that is live in the other register at the def point
only. It is not necessary to scan the set of overlapping live ranges,
this interference check can be done while computing the value mapping
required for the final live range join.
The new algorithm is prepared to handle more complicated conflict
resolution - We can allow overlapping live ranges with different values
as long as the differing lanes are undef or unused in the other
register.
The implementation in this patch doesn't do that yet, it creates code
that is nearly identical to the old algorithm's, except:
- The new stripCopies() function sees through multiple copies while
the old RegistersDefinedFromSameValue() only can handle one.
- There are a few rare cases where the new algorithm can erase an
IMPLICIT_DEF instuction that RegistersDefinedFromSameValue() couldn't
handle.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@163991 91177308-0d34-0410-b5e6-96231b3b80d8
Kill flags are removed more and more aggressively during the register
allocation passes, it is better to get information from LiveIntervals.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@163972 91177308-0d34-0410-b5e6-96231b3b80d8