BasicBlocks, so that it doesn't blindly procede in the presence of
large individual BasicBlocks. This addresses a class of code-size
expansion problems.
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it to visit instructions from the start of the function to the
end of the function in the first path. This greatly speeds up
some pathological cases (e.g. PR5150).
Try #3, this time with some unneeded debug info stuff removed
which was causing dead pointers to be added to the worklist.
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it to visit instructions from the start of the function to the
end of the function in the first path. This greatly speeds up
some pathological cases (e.g. PR5150).
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into a shuffle even if it was used by another insertelement. If the
visitation order of instcombine was wrong, this would turn a chain of
insertelements into a chain of shufflevectors, which was quite painful.
Since CollectShuffleElements handles these cases, the code can just
be nuked.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@83810 91177308-0d34-0410-b5e6-96231b3b80d8
input the the mul is a zext from bool, just that it is all zeros
other than the low bit. This fixes some phase ordering issues
that would cause us to miss some xforms in mul.ll when the worklist
is visited differently.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@83794 91177308-0d34-0410-b5e6-96231b3b80d8
it to visit instructions from the start of the function to the
end of the function in the first path. This greatly speeds up
some pathological cases (e.g. PR5150).
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@83790 91177308-0d34-0410-b5e6-96231b3b80d8
For now the metadata of sinked/hoisted instructions is still wrong, but that'll
be fixed when instructions will have debug metadata directly attached.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@83786 91177308-0d34-0410-b5e6-96231b3b80d8
done by condprop, but do it in a much more general form. The
basic idea is that we can do a limited form of tail duplication
in the case when we have a branch on a phi. Moving the branch
up in to the predecessor block makes instruction selection
much easier and encourages chained jump threadings.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@83759 91177308-0d34-0410-b5e6-96231b3b80d8
inserted only once, just use vector. Don't compute ExitBlocks unless we
need it, change std::sort to array_pod_sort.
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from GVN, this also speeds it up, inserts fewer PHI nodes (see the
testcase) and allows it to remove more loads (due to fewer PHI nodes
standing in the way).
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not just at the end. Add a big comment explaining when this could
be useful (which never happens for jump threading).
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DemoteRegToStack. This makes it more efficient (because it isn't
creating a ton of load/stores that are eventually removed by a later
mem2reg), and more slightly more effective (because those load/stores
don't get in the way of threading).
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constants used in inlining heuristics (especially
those used in more than one file). No functional change.
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and that will make Caller too big to inline, see if it
might be better to inline Caller into its callers instead.
This situation is described in PR 2973, although I haven't
tried the specific case in SPASS.
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to declare that they preserve other passes without needing to pull in
additional header file or library dependencies. Convert MachineFunctionPass
and CodeGenLICM to make use of this.
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already on the worklist, and print Visited when an instruction is about to be
visited. Net, on one input, this reduced the output size by at least 9x.
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for inlining.
When MallocInst goes away this code will be subsumed as part of
calls and work just fine...
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out of it, and jump threading, condprop and gvn are now getting
most of the benefit. This was approved by Nicholas and Nicolas.
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the new predicates I added) instead of going through a context and doing a
pointer comparison. Besides being cheaper, this allows a smart compiler
to turn the if sequence into a switch.
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phi nodes. Make sure to phi translate from the right block.
This fixes a llvm-building-llvm failure on GVN-PRE.cpp
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simple constants for the true/false value of the select. We now
do phi translation etc. This really fixes PR4895 :)
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that are phi nodes. Also tighten up FoldOpIntoPhi to treat constantexpr
operands to phis just like other variables, avoiding moving constantexpr
computations around.
Patch by Daniel Dunbar.
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This doesn't kick in too much because of phi translation issues,
but this can be resolved in the future.
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from a piece of a large store when both are in the same block.
This allows clang to compile the testcase in PR4216 to this code:
_test_bitfield:
movl 4(%esp), %eax
movl %eax, %ecx
andl $-65536, %ecx
orl $32962, %eax
andl $40186, %eax
orl %ecx, %eax
ret
This is not ideal, but is a whole lot better than the code produced
by llvm-gcc:
_test_bitfield:
movw $-32574, %ax
orw 4(%esp), %ax
andw $-25350, %ax
movw %ax, 4(%esp)
movw 7(%esp), %cx
shlw $8, %cx
movzbl 6(%esp), %edx
orw %cx, %dx
movzwl %dx, %ecx
shll $16, %ecx
movzwl %ax, %eax
orl %ecx, %eax
ret
and dramatically better than that produced by gcc 4.2:
_test_bitfield:
pushl %ebx
call L3
"L00000000001$pb":
L3:
popl %ebx
movl 8(%esp), %eax
leal 0(,%eax,4), %edx
sarb $7, %dl
movl %eax, %ecx
andl $7168, %ecx
andl $-7201, %ebx
movzbl %dl, %edx
andl $1, %edx
sall $5, %edx
orl %ecx, %ebx
orl %edx, %ebx
andl $24, %eax
andl $-58336, %ebx
orl %eax, %ebx
orl $32962, %ebx
movl %ebx, %eax
popl %ebx
ret
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@82439 91177308-0d34-0410-b5e6-96231b3b80d8
so that nonlocal and partially redundant loads can use it as well.
The testcase shows examples of craziness this can handle. This triggers
*many* times in 176.gcc.
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(and load -> load) when the base pointers must alias but when
they are different types. This occurs very very frequently in
176.gcc and other code that uses bitfields a lot.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@82399 91177308-0d34-0410-b5e6-96231b3b80d8
In getMallocArraySize(), fix bug in the case that array size is the product of 2 constants.
Extend isArrayMalloc() and getMallocArraySize() to handle case where malloc is used as char array.
Ensure that ArraySize in LowerAllocations::runOnBasicBlock() is correct type.
Extend Instruction::isSafeToSpeculativelyExecute() to handle malloc calls.
Add verification for malloc calls.
Reviewed by Dan Gohman.
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constants out of loops. These aren't covered by the regular LICM
pass, because in LLVM IR constants don't require separate
instructions. They're not always covered by the MachineLICM pass
either, because it doesn't know how to unfold folded constant-pool
loads. This is somewhat experimental at this point, and off by
default.
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phis, similar to the FoldPHIArgGEPIntoPHI change.
Also, delete some comments that don't reflect the code.
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more than one phi, since that leads to higher register pressure on
entry to the phi. This is especially problematic when the phi is in
a loop header, as it increases register pressure throughout the loop.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@81993 91177308-0d34-0410-b5e6-96231b3b80d8
argpromote to avoid invalidating an iterator. This fixes PR4977.
All clang tests now pass with expensive checking (on my system
at least).
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within the notional bounds of the static type of the getelementptr (which
is not the same as "inbounds") from GlobalOpt into a utility routine,
and use it in ConstantFold.cpp to check whether there are any mis-behaved
indices.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@81478 91177308-0d34-0410-b5e6-96231b3b80d8
loop exit edge -- new PHIs may be needed not only for the additional
splits that are made to preserve LoopSimplify form, but also for the
original split. Factor out the code that inserts new PHIs so that it
can be used for both. Remove LoopRotation.cpp's code for manually
updating LCSSA form, as it is now redundant. This fixes PR4934.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@81363 91177308-0d34-0410-b5e6-96231b3b80d8
that get created during loop unswitching, and fix SplitBlockPredecessors'
LCSSA updating code to create new PHIs instead of trying to just move
existing ones.
Also, optimize Loop::verifyLoop, since it gets called a lot. Use
searches on a sorted list of blocks instead of calling the "contains"
function, as is done in other places in the Loop class, since "contains"
does a linear search. Also, don't call verifyLoop from LoopSimplify or
LCSSA, as the PassManager is already calling verifyLoop as part of
LoopInfo's verifyAnalysis.
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extractelement operations into a bitcast of the pointer,
then a gep, then a scalar load. Disable this when the vector
only has one element, because it leads to infinite loops in
instcombine (PR4908).
This transformation seems like a really bad idea to me, as it
will likely disable CSE of vector load/stores etc and can be
better done in the code generator when profitable. This
goes all the way back to the first days of packed types,
r25299 specifically.
I'll let those people who care about the performance of vector
code decide what to do with this.
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compile-time constant integers or that are out of bounds for their
corresponding static array types. These can cause aliasing that
GlobalOpt assumes won't happen.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@81165 91177308-0d34-0410-b5e6-96231b3b80d8
an aggregate store overlapping a different aggregate store, despite
the stores having distinct addresses.
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is missing the inbounds flag. This is slightly conservative, but it
avoids problems with two constants pointing to the same address but
getting distinct entries in the Memory DenseMap.
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- I think there are more instances of this, but I think they are fixed in Dan's
incoming patch. This one was preventing me from doing a bugpoint reduction
though.
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Constant uniquing tables. This allows distinct ConstantExpr objects
with the same operation and different flags.
Even though a ConstantExpr "a + b" is either always overflowing or
never overflowing (due to being a ConstantExpr), it's still necessary
to be able to represent it both with and without overflow flags at
the same time within the IR, because the safety of the flag may
depend on the context of the use. If the constant really does overflow,
it wouldn't ever be safe to use with the flag set, however the use
may be in code that is never actually executed.
This also makes it possible to merge all the flags tests into a single test.
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that these passes are properly preserved.
Fix several transformation passes that claimed to preserve LoopSimplify
form but weren't.
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instead of a bool argument, and to do the dominator check itself.
This makes it eaiser to use when DominatorTree information is
available.
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Removed inverted flag form MaximumSpanningTree, also do not handle so much
information to MaximumSpanningTree.
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simplifylibcalls optimization is thus valid for C++ but not C.
It's not important enough to worry about for C++ apps, so just
remove it.
rdar://7191924
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don't alias. Remove an old and poorly reduced testcase that fails
with this transform for reasons unrelated to the original test.
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Add statistics for regular edge profiling, this enables the comparation of the
number of edges inserted by regular and optimal edge profiling.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@80668 91177308-0d34-0410-b5e6-96231b3b80d8
for sanity. This didn't turn up any bugs.
Change CallGraphNode to maintain its "callsite" information in the
call edges list as a WeakVH instead of as an instruction*. This fixes
a broad class of dangling pointer bugs, and makes CallGraph have a number
of useful invariants again. This fixes the class of problem indicated
by PR4029 and PR3601.
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changes: SimplifyDemandedBits can't use the builder yet because it
has the wrong insertion point. This fixes a crash building
MultiSource/Benchmarks/PAQ8p
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instead of CallGraphNode*'s. This also papers over a callgraph
problem where a pass (in this case, MemCpyOpt) introduces a new
function into the module (llvm.memset.i64) but doesn't add it to
the call graph (nor should it, since it is a function pass).
While it might be a good idea for MemCpyOpt to not synthesize
functions in a runOnFunction(), there is no need for FunctionAttrs
to be boneheaded, so fix it there. This fixes an assertion building
176.gcc.
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indirect function pointer, inline it, then go to delete the body.
The problem is that the callgraph had other references to the function,
though the inliner had no way to know it, so we got a dangling pointer
and an invalid iterator out of the deal.
The fix to this is pretty simple: stop the inliner from deleting the
function by knowing that there are references to it. Do this by making
CallGraphNodes contain a refcount. This requires moving deletion of
available_externally functions to the module-level cleanup sweep where
it belongs.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@80533 91177308-0d34-0410-b5e6-96231b3b80d8
argpromotion and structretpromote. Basically, when replacing
a function, they used the 'changeFunction' api which changes
the entry in the function map (and steals/reuses the callgraph
node).
This has some interesting effects: first, the problem is that it doesn't
update the "callee" edges in any callees of the function in the call graph.
Second, this covers for a major problem in all the CGSCC pass stuff, which
is that it is completely broken when functions are deleted if they *don't*
reuse a CGN. (there is a cute little fixme about this though :).
This patch changes the protocol that CGSCC passes must obey: now the CGSCC
pass manager copies the SCC and preincrements its iterator to avoid passes
invalidating it. This allows CGSCC passes to mutate the current SCC. However
multiple passes may be run on that SCC, so if passes do this, they are now
required to *update* the SCC to be current when they return.
Other less interesting parts of this patch are that it makes passes update
the CG more directly, eliminates changeFunction, and requires clients of
replaceCallSite to specify the new callee CGN if they are changing it.
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is itself a bitcast. Since we have gep(bitcast(bitcast(y))) in this
case, just wait for the two bitcasts to get zapped. This prevents
instcombine from confusing some aliasing stuff, and allows it to
directly eliminate the load in the testcase.
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workslist and is set to insert new instructions before the current one.
Convert a bunch of stuff that used to call InsertNewInstBefore over to
use it, greatly simplifying code and making it more natural.
There is still a lot more to go, but this is a good start.
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if the operand is not an instruction.
Simplify most uses of AddOperandsToWorkList to use AddValue and
inline it into the one remaining callsite.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@80488 91177308-0d34-0410-b5e6-96231b3b80d8
former looks too much like AddUsersToWorkList and keeps
confusing me.
Remove AddSoonDeadInstToWorklist and change its two callers
to do the same thing in a simpler way.
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into their callers. simplify ReplaceInstUsesWith. Make
EraseInstFromFunction only add operands to the worklist if
there aren't too many of them (this was a scalability win
for crazy programs that was only infrequently enforced).
Switch more code to using EraseInstFromFunction instead of
duplicating it inline. Change some fcmp/icmp optimizations
to modify fcmp/icmp in place instead of creating a new one
and deleting the old one just to change the predicate.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@80483 91177308-0d34-0410-b5e6-96231b3b80d8
does constant folding of gep's: this is already handled in
a more general way.
No functionality change.
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This implements the maximum spanning tree algorithm on CFGs according to
weights given by the ProfileEstimator. This is then used to implement Optimal
Edge Profiling.
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calls into a function and if the calls bring in arrays, try to merge
them together to reduce stack size. For example, in the testcase
we'd previously end up with 4 allocas, now we end up with 2 allocas.
As described in the comments, this is not really the ideal solution
to this problem, but it is surprisingly effective. For example, on
176.gcc, we end up eliminating 67 arrays at "gccas" time and another
24 at "llvm-ld" time.
One piece of concern that I didn't look into: at -O0 -g with
forced inlining this will almost certainly result in worse debug
info. I think this is acceptable though given that this is a case
of "debugging optimized code", and we don't want debug info to
prevent the optimizer from doing things anyway.
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and introduce a new Instruction::isIdenticalTo which tests for full
identity, including the SubclassOptionalData flags. Also, fix the
Instruction::clone implementations to preserve the SubclassOptionalData
flags. Finally, teach several optimizations how to handle
SubclassOptionalData correctly, given these changes.
This fixes the counterintuitive behavior of isIdenticalTo not comparing
the full value, and clone not returning an identical clone, as well as
some subtle bugs that could be caused by these.
Thanks to Nick Lewycky for reporting this, and for an initial patch!
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@80038 91177308-0d34-0410-b5e6-96231b3b80d8
sinking code, since they are special. If the loop preheader happens
to be the entry block of a function, don't sink static allocas
out of it. This fixes PR4775.
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This change speeds up llvm-gcc by more then 6% at "-O0 -g" (measured by compiling InstructionCombining.cpp!)
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the command line. This gives llvm-gcc developers
a way to control inlining (documented as "not intended
for end users").
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of an extracted block contains a PHI using a value defined in the extracted region.
With this patch, the partial inliner now passes MultiSource/Applications.
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member out of line. ftostr is not particularly speedy,
so that method is presumably not perf sensitive.
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by hand, and fix a few places that were using hasInitializer() that
appear to depend on the initializer value.
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try to use i686-darwin to build for arm-eabi, you'll quickly run into
several false assumptions that the target OS must be the same as the
host OS. These patches split $(OS) into $(HOST_OS) and $(TARGET_OS) to
help builds like "make check" and the test-suite able to cross
compile. Along the way a target of *-unknown-eabi is defined as
"Freestanding" so that TARGET_OS checks have something to work with.
Patch by Sandeep Patel!
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@79296 91177308-0d34-0410-b5e6-96231b3b80d8
vector (&Formals[0]). With this change llvm-gcc builds
with expensive checking enabled for C, C++ and Fortran.
While there, change a std::vector into a SmallVector.
This is partly gratuitous, but mostly because not all
STL vector implementations define the data method (and
it should be faster).
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@79237 91177308-0d34-0410-b5e6-96231b3b80d8
unfoldable references to a PHI node in the block being folded, and disable
the transformation in that case. The correct transformation of such PHI
nodes depends on whether BB dominates Succ, and dominance is expensive
to compute here. (Alternatively, it's possible to check whether any
uses are live, but that's also essentially a dominance calculation.
Another alternative is to use reg2mem, but it probably isn't a good idea to
use that in simplifycfg.)
Also, remove some incorrect code from CanPropagatePredecessorsForPHIs
which is made unnecessary with this patch: it didn't consider the case
where a PHI node in BB has multiple uses.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@79174 91177308-0d34-0410-b5e6-96231b3b80d8
the new load by the old load instead of by the extract element because
a store could have occurred between the load and extract element.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@78891 91177308-0d34-0410-b5e6-96231b3b80d8
