It does, after all.
RemoveCopyByCommutingDef rewrites the uses of one particular value
number in A. It doesn't know how to rewrite phi uses, so there can't be
any.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@139787 91177308-0d34-0410-b5e6-96231b3b80d8
There is only one legitimate use remaining, in addIntervalsForSpills().
All other calls to hasPHIKill() are only used to update PHIKill flags.
The addIntervalsForSpills() function is part of the old spilling
framework, only used by linearscan.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@139783 91177308-0d34-0410-b5e6-96231b3b80d8
Instead, let HasOtherReachingDefs() test for defs in B that overlap any
phi-defs in A as well. This test is slightly different, but almost
identical.
A perfectly precise test would only check those phi-defs in A that are
reachable from AValNo.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@139782 91177308-0d34-0410-b5e6-96231b3b80d8
The source live range is recomputed using shrinkToUses() which does
handle phis correctly. The hasPHIKill() condition was relevant in the
old days when ReMaterializeTrivialDef() tried to recompute the live
range itself.
The shrinkToUses() function will mark the original def as dead when no
more uses and phi kills remain. It is then removed by
runOnMachineFunction().
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@139781 91177308-0d34-0410-b5e6-96231b3b80d8
It is conservatively correct to keep the hasPHIKill flags, even after
deleting PHI-defs.
The calculation can be very expensive after taildup has created a
quadratic number of indirectbr edges in the CFG, and the hasPHIKill flag
isn't used for anything after RenumberValues().
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@139780 91177308-0d34-0410-b5e6-96231b3b80d8
An improper SlotIndex->VNInfo lookup was leading to unsafe copy removal.
Fixes PR10920 401.bzip2 miscompile with no IV rewrite.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@139765 91177308-0d34-0410-b5e6-96231b3b80d8
will ignore the erasedOnReboot option, and properly escape the
backslash in "C:\TEMP". Thanks to Aaron and Francois.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@139755 91177308-0d34-0410-b5e6-96231b3b80d8
Clean up register list handling in general a bit to explicitly check things
like all the registers being from the same register class.
rdar://8883573
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@139707 91177308-0d34-0410-b5e6-96231b3b80d8
THe LRE_DidCloneVirtReg callback may be called with vitual registers
that RAGreedy doesn't even know about yet. In that case, there are no
data structures to update.
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When a back-copy is hoisted to the nearest common dominator, keep
looking up the dominator tree for a less loopy dominator, and place the
back-copy there instead.
Don't do this when a single existing back-copy dominates all the others.
Assume the client knows what he is doing, and keep the dominating
back-copy.
This prevents us from hoisting back-copies into loops in most cases. If
a value is defined in a loop with multiple exits, we may still hoist
back-copies into that loop. That is the speed/size tradeoff.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@139698 91177308-0d34-0410-b5e6-96231b3b80d8
- Add TSFlags for the instruction formats. The idea here is to use
as much encoding as possible from getBinaryCodeForInstr, and having
TSFLags formats for that would make it easier to encode most part
of the instructions (since Mips encodings are pretty straightforward)
- Improve the mips mechanism for compilation callback
- Add Mips specific code for invalidating the instruction cache
- Next patch will address wrong tablegen encoding
Commit msg added by my own but the patch is from Sasa Stankovic.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@139688 91177308-0d34-0410-b5e6-96231b3b80d8
alignment check for 256-bit classes more strict. There're no testcases
but we catch more folding cases for AVX while running single and multi
sources in the llvm testsuite.
Since some 128-bit AVX instructions have different number of operands
than their SSE counterparts, they are placed in different tables.
256-bit AVX instructions should also be added in the table soon. And
there a few more 128-bit versions to handled, which should come in
the following commits.
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- Add enum SymbolType and function getSymbolType()
- Add function isGlobal() - it's returns true for symbols that can be used in another objects, such as library functions.
- Rename function getAddress() to getOffset() and add new function getAddress(), because currently getAddress() returns section offset of symbol first byte. new getAddress() return symbol address.
- Change usage SymbolRef::getAddress() to getOffset() in tools/llvm-nm and tools/llvm-objdump.
Patch by Danil Malyshev!
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This is only one half of it, the part that caches address ranges from the DIEs when .debug_aranges is
not available will be ported soon.
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#line directives with the needed support in the lexer. Next will be to build
a simple file/line# table mapping source SMLoc's for later use by diagnostics.
And the last step will be to get the diagnostics to use the mapping for file
and line numbers.
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When a ParentVNI maps to multiple defs in a new interval, its live range
may still be derived directly from RegAssign by transferValues().
On the other hand, when instructions have been rematerialized or
hoisted, it may be necessary to completely recompute live ranges using
LiveRangeCalc::extend() to all uses.
Use a bit in the value map to indicate that a live range must be
recomputed. Rename markComplexMapped() to forceRecompute().
This fixes some live range verification errors when
-split-spill-mode=size hoists back-copies by recomputing source ranges
when RegAssign kills can't be moved.
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Whenever the complement interval is defined by multiple copies of the
same value, hoist those back-copies to the nearest common dominator.
This ensures that at most one copy is inserted per value in the
complement inteval, and no phi-defs are needed.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@139651 91177308-0d34-0410-b5e6-96231b3b80d8
This introduces a new library to LLVM: libDebugInfo. It will provide debug information
parsing to LLVM. Much of the design and some of the code is taken from the LLDB project.
It also contains an llvm-dwarfdump tool that can dump the abbrevs and DIEs from an
object file. It can be used to write tests for DWARF input and output easily.
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It is an endian-aware helper that can read data from a StringRef. It will
come in handy for DWARF parsing. This class is inspired by LLDB's
DataExtractor, but is stripped down to the bare minimum needed for DWARF.
Comes with unit tests!
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more strict about the alignment checking. This was found by inspection
and I don't have any testcases so far, although the llvm testsuite runs
without any problem.
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This function is used to flag values where the complement interval may
overlap other intervals. Call it from overlapIntv, and use the flag to
fully recompute those live ranges in transferValues().
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Three out of four clients prefer this interface which is consistent with
extendIntervalEndTo() and LiveRangeCalc::extend().
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The complement interval may overlap the other intervals created, so use
a separate LiveRangeCalc instance to compute its live range.
A LiveRangeCalc instance can only be shared among non-overlapping
intervals.
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SplitKit will soon need two copies of these data structures, and the
algorithms will also be useful when LiveIntervalAnalysis becomes
independent of LiveVariables.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@139572 91177308-0d34-0410-b5e6-96231b3b80d8
Splitting a landing pad takes considerable care because of PHIs and other
nasties. The problem is that the jump table needs to jump to the landing pad
block. However, the landing pad block can be jumped to only by an invoke
instruction. So we clone the landingpad instruction into its own basic block,
have the invoke jump to there. The landingpad instruction's basic block's
successor is now the target for the jump table.
But because of PHI nodes, we need to create another basic block for the jump
table to jump to. This is definitely a hack, because the values for the PHI
nodes may not be defined on the edge from the jump table. But that's okay,
because the jump table is simply a construct to mimic what is happening in the
CFG. So the values are mysteriously there, even though there is no value for the
PHI from the jump table's edge (hence calling this a hack).
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No tests; these changes aren't really interesting in the sense that the logic is the same for volatile and atomic.
I believe this completes all of the changes necessary for the optimizer to handle loads and stores correctly. I'm going to try and come up with some additional testing, though.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@139533 91177308-0d34-0410-b5e6-96231b3b80d8
However with this fix it does now.
Basically the operand order for the x86 target specific node
is not the same as the instruction, but since the intrinsic need that
specific order at the instruction definition, just change the order
during legalization. Also, there were some wrong invertions of condition
codes, such as GE => LE, GT => LT, fix that too. Fix PR10907.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@139528 91177308-0d34-0410-b5e6-96231b3b80d8
SplitKit always computes a complement live range to cover the places
where the original live range was live, but no explicit region has been
allocated.
Currently, the complement live range is created to be as small as
possible - it never overlaps any of the regions. This minimizes
register pressure, but if the complement is going to be spilled anyway,
that is not very important. The spiller will eliminate redundant
spills, and hoist others by making the spill slot live range overlap
some of the regions created by splitting. Stack slots are cheap.
This patch adds the interface to enable spill modes in SplitKit. In
spill mode, SplitKit will assume that the complement is going to spill,
so it will allow it to overlap regions in order to avoid back-copies.
By doing some of the spiller's work early, the complement live range
becomes simpler. In some cases, it can become much simpler because no
extra PHI-defs are required. This will speed up both splitting and
spilling.
This is only the interface to enable spill modes, no implementation yet.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@139500 91177308-0d34-0410-b5e6-96231b3b80d8
Undo the changes from r139285 which added custom lowering to vselect.
Add tablegen lowering for vselect.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@139479 91177308-0d34-0410-b5e6-96231b3b80d8
assert("not implemented for target shuffle node");
to:
assert(0 && "not implemented for target shuffle node");
This causes a test failure in CodeGen/X86/palignr.ll which has
been marked as XFAIL for the time being.
Test failure filed at PR10901.
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better.
Don't immediately give up when an add operation can't be trivially
sign/zero-extended within a loop. If it has NSW/NUW flags, generate a
new expression with sign extended (non-recurrent) operand. As before,
if SCEV says that all sign extends are loop invariant, then we can
widen the operation.
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such.
I'm doing this now for completeness because I can't think of/remember
any reason that it was left out. I'm not sure it will help anything,
but if we don't do it we need to explain why in comments.
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In some cases such as interpreters using indirectbr, the CFG can be very
complicated, and live range splitting may be forced to insert a large
number of phi-defs. When that happens, traceSiblingValue can spend a
lot of time zipping around in the CFG looking for defs and reloads.
This patch causes more information to be cached in SibValues, and the
cached values are used to terminate searches early. This speeds up
spilling by 20x in one interpreter test case. For more typical code,
this is just a 10% speedup of spilling.
The previous version had bugs that caused miscompilations. They have
been fixed.
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removing support for Mips1 and Mips2.
This change and the ones that follow have been discussed with and approved by
Bruno.
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single field (Flags), which is a bitwise OR of items from the TB_*
enum. This makes it easier to add new information in the future.
* Gives every static array an equivalent layout: { RegOp, MemOp, Flags }
* Adds a helper function, AddTableEntry, to avoid duplication of the
insertion code.
* Renames TB_NOT_REVERSABLE to TB_NO_REVERSE.
* Adds TB_NO_FORWARD, which is analogous to TB_NO_REVERSE, except that
it prevents addition of the Reg->Mem entry. (This is going to be used
by Native Client, in the next CL).
Patch by David Meyer
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@139311 91177308-0d34-0410-b5e6-96231b3b80d8
in Nadav's r139285 and r139287 commits.
1) Rename vsel.ll to a more descriptive name
2) Change the order of BLEND operands to "Op1, Op2, Cond", this is
necessary because PBLENDVB is already used in different places with
this order, and it was being emitted in the wrong way for vselect
3) Add AVX patterns and tests for the same SSE41 instructions
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@139305 91177308-0d34-0410-b5e6-96231b3b80d8
More cleanup of the general indexed addressing T2 instructions. Still more to
do, especially for stores.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@139272 91177308-0d34-0410-b5e6-96231b3b80d8
Adjust encoding of writeback load/store instructions to better reflect the
way the operand types are represented.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@139270 91177308-0d34-0410-b5e6-96231b3b80d8
The immediate offset of the non-writeback i8 form (encoding T4) allows
negative offsets only. The positive offset form of the encoding is the
LDRT instruction. Immediate offsets in the range [0,255] use encoding T3
instead.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@139254 91177308-0d34-0410-b5e6-96231b3b80d8
In some cases such as interpreters using indirectbr, the CFG can be very
complicated, and live range splitting may be forced to insert a large
number of phi-defs. When that happens, traceSiblingValue can spend a
lot of time zipping around in the CFG looking for defs and reloads.
This patch causes more information to be cached in SibValues, and the
cached values are used to terminate searches early. This speeds up
spilling by 20x in one interpreter test case. For more typical code,
this is just a 10% speedup of spilling.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@139247 91177308-0d34-0410-b5e6-96231b3b80d8
There is no 16-bit wide encoding, so the .w suffix isn't needed (indeed, isn't
documented as allowed). Also add the missing '!' token on the _UPD
variant.
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Choose 32-bit vs. 16-bit encoding when there's no .w suffix in post-processing
as match classes are insufficient to handle the context-sensitiveness of
the writeback operand's legality for the 16-bit encodings.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@139242 91177308-0d34-0410-b5e6-96231b3b80d8
(The fix for the related failures on x86 is going to be nastier because we actually need Acquire memoperands attached to the atomic load instrs, etc.)
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@139221 91177308-0d34-0410-b5e6-96231b3b80d8
with a vector condition); such selects become VSELECT codegen nodes.
This patch also removes VSETCC codegen nodes, unifying them with SETCC
nodes (codegen was actually often using SETCC for vector SETCC already).
This ensures that various DAG combiner optimizations kick in for vector
comparisons. Passes dragonegg bootstrap with no testsuite regressions
(nightly testsuite as well as "make check-all"). Patch mostly by
Nadav Rotem.
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Now the 'S' instructions, e.g. ADDS, treat S bit as optional operand as well.
Also fix isel hook to correctly set the optional operand.
rdar://10073745
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Even if there's no mode switch performed, the .code directive should still
be sent to the output streamer. Otherwise, for example, an output asm stream
is not equivalent to the input stream which generated it (a dependency on
the input target triple arm vs. thumb is introduced which was not originally
there).
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init.trampoline and adjust.trampoline intrinsics, into two intrinsics
like in GCC. While having one combined intrinsic is tempting, it is
not natural because typically the trampoline initialization needs to
be done in one function, and the result of adjust trampoline is needed
in a different (nested) function. To get around this llvm-gcc hacks the
nested function lowering code to insert an additional parent variable
holding the adjust.trampoline result that can be accessed from the child
function. Dragonegg doesn't have the luxury of tweaking GCC code, so it
stored the result of adjust.trampoline in the memory GCC set aside for
the trampoline itself (this is always available in the child function),
and set up some new memory (using an alloca) to hold the trampoline.
Unfortunately this breaks Go which allocates trampoline memory on the
heap and wants to use it even after the parent has exited (!). Rather
than doing even more hacks to get Go working, it seemed best to just use
two intrinsics like in GCC. Patch mostly by Sanjoy Das.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@139140 91177308-0d34-0410-b5e6-96231b3b80d8
instructions are more aligned than the CPU requires, and adds some additional
directives, to follow in future patches. Patch by David Meyer!
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@139125 91177308-0d34-0410-b5e6-96231b3b80d8
- Drop support for X >u 0, it's equivalent to X != 0 and should be canonicalized into the latter.
- Add X < 1 -> unlikely, which is what instcombine canonicalizes X <= 0 into.
- Add X > -1 -> likely, which is what instcombine canonicalizes X >= 0 into.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@139110 91177308-0d34-0410-b5e6-96231b3b80d8
call. The call may be in the same BB as the landingpad instruction. If that's
the case, then inserting the loads after the landingpad inst, but before the
extractvalues, causes undefined behavior.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@139088 91177308-0d34-0410-b5e6-96231b3b80d8
If we have a chain of zext -> assert_zext -> zext -> use, the first zext would get simplified away because of the later zext, and then the later zext would get simplified away because of the assert. The solution is to teach SimplifyDemandedBits that assert_zext demands all of the high bits of its input, rather than only those demanded by its users. No testcase because the only example I have manifests as llvm-gcc miscompiling LLVM, and I haven't found a smaller case that reproduces this problem.
Fixes <rdar://problem/10063365>.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@139059 91177308-0d34-0410-b5e6-96231b3b80d8
The explanation about a 0 argument being materialized as xor is no
longer valid. Rematerialization will check if EFLAGS is live before
clobbering it.
The code produced by X86TargetLowering::EmitLoweredSelect does not
clobber EFLAGS.
This causes one less testb instruction to be generated in the cmov.ll
test case.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@139057 91177308-0d34-0410-b5e6-96231b3b80d8
Tweak handling of IT blocks a bit to enable this. The differentiation between
B and Bcc needs special sauce.
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For other shift and rotate instructions, too. Tests for those forthcoming
as I work my way through the ISA.
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slots. This fixes a bug where the number of nodes coming into the PHI node may
not equal the number of predecessors. E.g., two or more landingpad instructions
may require a PHI before reaching the eh.exception and eh.selector instructions.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@139035 91177308-0d34-0410-b5e6-96231b3b80d8
This changes loop unrolling to use the same mechanism for trip count
computation as indvars. This is a stronger check that tends to unroll
more loops. A very common side-effect is that many single iteration
loops will be removed sooner. The real goal was simply to remove
dependence on canonical IVs.
x86 is break even.
ARM performance changes to expect (+ is good):
External/SPEC/CFP2000/183.equake/183.equake +13%
SingleSource/Benchmarks/Dhrystone/fldry +21%
MultiSource/Applications/spiff/spiff +3%
SingleSource/Benchmarks/Stanford/Puzzle -14%
The Puzzle regression is actually an improvement in loop optimization
that defeats GVN: rdar://problem/10065079.
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Perform the upgrading in steps.
* First, create a map of the invokes to the EH intrinsics.
* Next, take that mapping and determine if the invoke's unwind destination has a
single predecessor. If not, then create a new empty block to hold the new
landingpad instruction.
* Create a landingpad instruction into the uwnind destination. Fill it with the
values from the old selector. Map the old intrinsic calls to the new
landingpad values (there may be multiple landingpad instructions per instrinic
call pairs).
* Go through the old intrinsic calls, create a PHI node when necessary, and then
replace their values with the new values from the landingpad instructions.
* Delete all dead instructions.
* ???
* Profit!
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to be unreliable on platforms which require memcpy calls, and it is
complicating broader legalize cleanups. It is hoped that these cleanups
will make memcpy byval easier to implement in the future.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@138977 91177308-0d34-0410-b5e6-96231b3b80d8
- On COFF the .lcomm directive has an alignment argument.
- On ELF we fall back to .local + .comm
Based on a patch by NAKAMURA Takumi.
Fixes PR9337, PR9483 and PR10128.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@138976 91177308-0d34-0410-b5e6-96231b3b80d8
An instruction may define part of a register where the other bits are
undefined. In that case, it is safe to rematerialize the instruction.
For example:
%vreg2:ssub_0<def> = VLDRS <cp#0>, 0, pred:14, pred:%noreg, %vreg2<imp-def>
The extra <imp-def> operand indicates that the instruction does not read
the other parts of the virtual register, so a remat is safe.
This patch simply allows multiple def operands for the virtual register.
It is MI->readsVirtualRegister() that determines if we depend on a
previous value so remat is impossible.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@138953 91177308-0d34-0410-b5e6-96231b3b80d8
The problem is fixed for all register allocators by r138944, so this
patch is no longer necessary.
<rdar://problem/10032939>
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@138945 91177308-0d34-0410-b5e6-96231b3b80d8
An instruction that redefines only part of a larger register can never
be rematerialized since the virtual register value depends on the old
value in other parts of the register.
This was fixed for the inline spiller in r138794. This patch fixes the
problem for all register allocators, and includes a small test case.
<rdar://problem/10032939>
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@138944 91177308-0d34-0410-b5e6-96231b3b80d8
Added canClobberReachingPhysRegUse() to handle a particular pattern in
which a two-address instruction could be forced to interfere with
EFLAGS, causing a compare to be unnecessarilly cloned.
Fixes rdar://problem/5875261
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@138924 91177308-0d34-0410-b5e6-96231b3b80d8
