This patch migrates the memcmp optimizations from the simplify-libcalls
pass into the instcombine library call simplifier.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@167683 91177308-0d34-0410-b5e6-96231b3b80d8
This patch migrates the strstr optimizations from the simplify-libcalls
pass into the instcombine library call simplifier.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@167682 91177308-0d34-0410-b5e6-96231b3b80d8
In some cases the library call simplifier may need to replace instructions
other than the library call being simplified. In those cases it may be
necessary for clients of the simplifier to override how the replacements
are actually done. As such, a new overrideable method for replacing
instructions was added to LibCallSimplifier.
A new subclass of LibCallSimplifier is also defined which overrides
the instruction replacement method. This is because the instruction
combiner defines its own replacement method which updates the worklist
when instructions are replaced.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@167681 91177308-0d34-0410-b5e6-96231b3b80d8
This patch migrates the strcspn optimizations from the simplify-libcalls
pass into the instcombine library call simplifier.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@167675 91177308-0d34-0410-b5e6-96231b3b80d8
Several of the simplifiers migrated from the simplify-libcalls pass to
the instcombine pass were not correctly checking the target library
information to gate the simplifications. This patch ensures that the
check is made.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@167660 91177308-0d34-0410-b5e6-96231b3b80d8
If the arrays are found to be disjoint then we run the vectorized version of
the loop. If they are not, we run the scalar code.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@167608 91177308-0d34-0410-b5e6-96231b3b80d8
This patch migrates the strspn optimizations from the simplify-libcalls
pass into the instcombine library call simplifier.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@167568 91177308-0d34-0410-b5e6-96231b3b80d8
The new analysis is not yet ready for prime time. It has a *critical*
flawed assumption, and some troubling shortages of testing. Until it's
been hammered into better shape, let's stick with the working code. This
should be easy to revert itself when the analysis is ready.
Fixes PR14241, a miscompile of any memcpy-able loop which uses a pointer
as the induction mechanism. If you have been seeing miscompiles in this
revision range, you really want to test with this backed out. The
results of this miscompile are a bit subtle as they can lead to
downstream passes concluding things are impossible which are in fact
possible.
Thanks to David Blaikie for the majority of the reduction of this
miscompile. I'll be checking in the test case in a non-revert commit.
Revesions reverted here:
r167045: LoopIdiom: Fix a serious missed optimization: we only turned
top-level loops into memmove.
r166877: LoopIdiom: Add checks to avoid turning memmove into an infinite
loop.
r166875: LoopIdiom: Recognize memmove loops.
r166874: LoopIdiom: Replace custom dependence analysis with
DependenceAnalysis.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@167286 91177308-0d34-0410-b5e6-96231b3b80d8
test/Transforms/GVN/rle.ll if the (currently disabled) check for a
pointer type in getIntPtrType is turned on.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@167285 91177308-0d34-0410-b5e6-96231b3b80d8
When target cost information is available, compute explicit costs of inserting and
extracting values from vectors. At this point, all costs are estimated using the
target information, and the chain-depth heuristic is not needed. As a result, it is now, by
default, disabled when using target costs.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@167256 91177308-0d34-0410-b5e6-96231b3b80d8
r165941: Resubmit the changes to llvm core to update the functions to
support different pointer sizes on a per address space basis.
Despite this commit log, this change primarily changed stuff outside of
VMCore, and those changes do not carry any tests for correctness (or
even plausibility), and we have consistently found questionable or flat
out incorrect cases in these changes. Most of them are probably correct,
but we need to devise a system that makes it more clear when we have
handled the address space concerns correctly, and ideally each pass that
gets updated would receive an accompanying test case that exercises that
pass specificaly w.r.t. alternate address spaces.
However, from this commit, I have retained the new C API entry points.
Those were an orthogonal change that probably should have been split
apart, but they seem entirely good.
In several places the changes were very obvious cleanups with no actual
multiple address space code added; these I have not reverted when
I spotted them.
In a few other places there were merge conflicts due to a cleaner
solution being implemented later, often not using address spaces at all.
In those cases, I've preserved the new code which isn't address space
dependent.
This is part of my ongoing effort to clean out the partial address space
code which carries high risk and low test coverage, and not likely to be
finished before the 3.2 release looms closer. Duncan and I would both
like to see the above issues addressed before we return to these
changes.
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getIntPtrType support for multiple address spaces via a pointer type,
and also introduced a crasher bug in the constant folder reported in
PR14233.
These commits also contained several problems that should really be
addressed before they are re-committed. I have avoided reverting various
cleanups to the DataLayout APIs that are reasonable to have moving
forward in order to reduce the amount of churn, and minimize the number
of commits that were reverted. I've also manually updated merge
conflicts and manually arranged for the getIntPtrType function to stay
in DataLayout and to be defined in a plausible way after this revert.
Thanks to Duncan for working through this exact strategy with me, and
Nick Lewycky for tracking down the really annoying crasher this
triggered. (Test case to follow in its own commit.)
After discussing with Duncan extensively, and based on a note from
Micah, I'm going to continue to back out some more of the more
problematic patches in this series in order to ensure we go into the
LLVM 3.2 branch with a reasonable story here. I'll send a note to
llvmdev explaining what's going on and why.
Summary of reverted revisions:
r166634: Fix a compiler warning with an unused variable.
r166607: Add some cleanup to the DataLayout changes requested by
Chandler.
r166596: Revert "Back out r166591, not sure why this made it through
since I cancelled the command. Bleh, sorry about this!
r166591: Delete a directory that wasn't supposed to be checked in yet.
r166578: Add in support for getIntPtrType to get the pointer type based
on the address space.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@167221 91177308-0d34-0410-b5e6-96231b3b80d8
When target costs are available, use them to account for the costs of
shuffles on internal edges of the DAG of candidate pairs.
Because the shuffle costs here are currently for only the internal edges,
the current target cost model is trivial, and the chain depth requirement
is still in place, I don't yet have an easy test
case. Nevertheless, by looking at the debug output, it does seem to do the right
think to the effective "size" of each DAG of candidate pairs.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@167217 91177308-0d34-0410-b5e6-96231b3b80d8
- Use value handle tricks to communicate use replacements instead of forgetLoop, this is a lot faster.
- Move the "big hammer" out of the main loop so it's not called for every instruction.
This should recover most (if not all) compile time regressions introduced by this code.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@167136 91177308-0d34-0410-b5e6-96231b3b80d8
BBVectorize would, except for loads and stores, always fuse instructions
so that the first instruction (in the current source order) would always
represent the low part of the input vectors and the second instruction
would always represent the high part. This lead to too many shuffles
being produced because sometimes the opposite order produces fewer of them.
With this change, BBVectorize tracks the kind of pair connections that form
the DAG of candidate pairs, and uses that information to reorder the pairs to
avoid excess shuffles. Using this information, a future commit will be able
to add VTTI-based shuffle costs to the pair selection procedure. Importantly,
the number of remaining shuffles can now be estimated during pair selection.
There are some trivial instruction reorderings in the test cases, and one
simple additional test where we certainly want to do a reordering to
avoid an unnecessary shuffle.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@167122 91177308-0d34-0410-b5e6-96231b3b80d8
This patch migrates the strto* optimizations from the simplify-libcalls
pass into the instcombine library call simplifier.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@167119 91177308-0d34-0410-b5e6-96231b3b80d8
By propagating the value for the switch condition, LLVM can now build
lookup tables for code such as:
switch (x) {
case 1: return 5;
case 2: return 42;
case 3: case 4: case 5:
return x - 123;
default:
return 123;
}
Given that x is known for each case, "x - 123" becomes a constant for
cases 3, 4, and 5.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@167115 91177308-0d34-0410-b5e6-96231b3b80d8
This patch migrates the strpbrk optimizations from the simplify-libcalls
pass into the instcombine library call simplifier.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@167105 91177308-0d34-0410-b5e6-96231b3b80d8
This patch migrates the strlen optimizations from the simplify-libcalls
pass into the instcombine library call simplifier.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@167103 91177308-0d34-0410-b5e6-96231b3b80d8
This patch migrates the strncpy optimizations from the simplify-libcalls
pass into the instcombine library call simplifier.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@167102 91177308-0d34-0410-b5e6-96231b3b80d8
This is important for loops in the LAPACK test-suite.
These loops start at 1 because they are auto-converted from fortran.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@167084 91177308-0d34-0410-b5e6-96231b3b80d8
This patch migrates the stpcpy optimizations from the simplify-libcalls
pass into the instcombine library call simplifier. Note that the
__stpcpy_chk simplifications were migrated in a previous commit.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@167083 91177308-0d34-0410-b5e6-96231b3b80d8
r166198 migrated the strcpy optimization to instcombine. The strcpy
simplifier that was migrated from Transforms/Scalar/SimplifyLibCalls.cpp
was also doing some __strcpy_chk simplifications. Those fortified
simplifications were migrated as well, but introduced a bug in the
__stpcpy_chk simplifier in the process. This happened because the
__strcpy_chk and __stpcpy_chk simplifiers were both mapped to StrCpyChkOpt
which was updated with simplifications that worked for __strcpy_chk, but
not __stpcpy_chk.
This patch fixes the problem by adding proper test coverage and creating a
new simplifier for __stpcpy_chk (instead of sharing one with __strcpy_chk).
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@167082 91177308-0d34-0410-b5e6-96231b3b80d8
integers in that the code to handle split alloca-wide integer loads or
stores doesn't come first. It should, for the same reasons as with
integers, and the PR attests to that. Also had to fix a busted assert in
that this test case also covers.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@167051 91177308-0d34-0410-b5e6-96231b3b80d8
Instead of recomputing relative pointer information just prior to fusing,
cache this information (which also needs to be computed during the
candidate-pair selection process). This cuts down on the total number of
SE queries made, and also is a necessary intermediate step on the road toward
including shuffle costs in the pair selection procedure.
No functionality change is intended.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@167049 91177308-0d34-0410-b5e6-96231b3b80d8
Stop propagating the FlipMemInputs variable into the routines that
create the replacement instructions. Instead, just flip the arguments
of those routines. This allows for some associated cleanup (not all
of which is done here). No functionality change is intended.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@167042 91177308-0d34-0410-b5e6-96231b3b80d8
SE was being called during the instruction-fusion process (when the result
is unreliable, and thus ignored). No functionality change is intended.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@167037 91177308-0d34-0410-b5e6-96231b3b80d8
When the switch-to-lookup tables transform landed in SimplifyCFG, it
was pointed out that this could be inappropriate for some targets.
Since there was no way at the time for the pass to know anything about
the target, an awkward reverse-transform was added in CodeGenPrepare
that turned lookup tables back into switches for some targets.
This patch uses the new TargetTransformInfo to determine if a
switch should be transformed, and removes
CodeGenPrepare::ConvertLoadToSwitch.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@167011 91177308-0d34-0410-b5e6-96231b3b80d8
checks to avoid performing compile-time arithmetic on PPCDoubleDouble.
Now that APFloat supports arithmetic on PPCDoubleDouble, those checks
are no longer needed, and we can treat the type like any other.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@166958 91177308-0d34-0410-b5e6-96231b3b80d8
wrapper returns a vector of integers when passed a vector of pointers) by having
getIntPtrType itself return a vector of integers in this case. Outside of this
wrapper, I didn't find anywhere in the codebase that was relying on the old
behaviour for vectors of pointers, so give this a whirl through the buildbots.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@166939 91177308-0d34-0410-b5e6-96231b3b80d8
split module can see each other. If it is keeping a symbol that already has
a non local linkage, it doesn't need to change it.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@166908 91177308-0d34-0410-b5e6-96231b3b80d8
output of both
llvm-extract foo.ll -func=bar
and
llvm-extract foo.ll -func=bar -delete
so the two new files could not be linked together anymore. With this change
alias are handled almost like functions and global variables. Almost because
with alias we cannot just clear the initializer/body, we have to create a new
declaration and replace the alias with it.
The net result is that now the output of the above commands can be linked
even if foo.ll has aliases.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@166907 91177308-0d34-0410-b5e6-96231b3b80d8
This turns loops like
for (unsigned i = 0; i != n; ++i)
p[i] = p[i+1];
into memmove, which has a highly optimized implementation in most libcs.
This was really easy with the new DependenceAnalysis :)
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@166875 91177308-0d34-0410-b5e6-96231b3b80d8
Requires a lot less code and complexity on loop-idiom's side and the more
precise analysis can catch more cases, like the one I included as a test case.
This also fixes the edge-case miscompilation from PR9481.
Compile time performance seems to be slightly worse, but this is mostly due
to an extra LCSSA run scheduled by the PassManager and should be fixed there.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@166874 91177308-0d34-0410-b5e6-96231b3b80d8
The monolithic interface for instruction costs has been split into
several functions. This is the corresponding change. No functionality
change is intended.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@166865 91177308-0d34-0410-b5e6-96231b3b80d8
Add getCostXXX calls for different families of opcodes, such as casts, arithmetic, cmp, etc.
Port the LoopVectorizer to the new API.
The LoopVectorizer now finds instructions which will remain uniform after vectorization. It uses this information when calculating the cost of these instructions.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@166836 91177308-0d34-0410-b5e6-96231b3b80d8
list of externals. This makes sense since a shared library with no symbols
can still be useful if it has static constructors.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@166795 91177308-0d34-0410-b5e6-96231b3b80d8
This is currently true, but may change when DA grows more aggressive caching.
Without this setting it's impossible to use DA from a LoopPass because DA is a
function pass and cannot be properly scheduled in between LoopPasses. The
LoopManager reacts to this with an infinite loop which made this really annoying
to debug.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@166788 91177308-0d34-0410-b5e6-96231b3b80d8
The LoopSimplify bug is pretty harmless because the loop goes from unanalyzable
to analyzable but the LCSSA bug is very nasty. It only comes into play with a
specific order of the LoopPassManager worklist and can cause actual
miscompilations, when a SCEV refers to a value that has been replaced with PHI
node. SCEVExpander may then insert code into the wrong place, either violating
domination or randomly miscompiling stuff.
Comes with an extensive test case reduced from the test-suite with
bugpoint+SCEVValidator.
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This is needed so that perl's SHA can be compiled (otherwise
BBVectorize takes far too long to find its fixed point).
I'll try to come up with a reduced test case.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@166738 91177308-0d34-0410-b5e6-96231b3b80d8
This is the first of several steps to incorporate information from the new
TargetTransformInfo infrastructure into BBVectorize. Two things are done here:
1. Target information is used to determine if it is profitable to fuse two
instructions. This means that the cost of the vector operation must not
be more expensive than the cost of the two original operations. Pairs that
are not profitable are no longer considered (because current cost information
is incomplete, for intrinsics for example, equal-cost pairs are still
considered).
2. The 'cost savings' computed for the profitability check are also used to
rank the DAGs that represent the potential vectorization plans. Specifically,
for nodes of non-trivial depth, the cost savings is used as the node
weight.
The next step will be to incorporate the shuffle costs into the DAG weighting;
this will give the edges of the DAG weights as well. Once that is done, when
target information is available, we should be able to dispense with the
depth heuristic.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@166716 91177308-0d34-0410-b5e6-96231b3b80d8
The isValueEqualityComparison() guard at the top of SimplifySwitch()
only applies to some of the possible transformations.
The newer transformations work just fine on large switches, and the
check on predecessor count is nonsensical.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@166710 91177308-0d34-0410-b5e6-96231b3b80d8
smaller integer loads and stores.
The high-level motivation is that the frontend sometimes generates
a single whole-alloca integer load or store during ABI lowering of
splittable allocas. We need to be able to break this apart in order to
see the underlying elements and properly promote them to SSA values. The
hope is that this fixes some performance regressions on x86-32 with the
new SROA pass.
Unfortunately, this causes quite a bit of churn in the test cases, and
bloats some IR that comes out. When we see an alloca that consists soley
of bits and bytes being extracted and re-inserted, we now do some
splitting first, before building widened integer "bucket of bits"
representations. These are always well folded by instcombine however, so
this shouldn't actually result in missed opportunities.
If this splitting of all-integer allocas does cause problems (perhaps
due to smaller SSA values going into the RA), we could potentially go to
some extreme measures to only do this integer splitting trick when there
are non-integer component accesses of an alloca, but discovering this is
quite expensive: it adds yet another complete walk of the recursive use
tree of the alloca.
Either way, I will be watching build bots and LNT bots to see what
fallout there is here. If anyone gets x86-32 numbers before & after this
change, I would be very interested.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@166662 91177308-0d34-0410-b5e6-96231b3b80d8
%V = mul i64 %N, 4
%t = getelementptr i8* bitcast (i32* %arr to i8*), i32 %V
into
%t1 = getelementptr i32* %arr, i32 %N
%t = bitcast i32* %t1 to i8*
incorporating the multiplication into the getelementptr.
This happens all the time in dragonegg, for example for
int foo(int *A, int N) {
return A[N];
}
because gcc turns this into byte pointer arithmetic before it hits the plugin:
D.1590_2 = (long unsigned int) N_1(D);
D.1591_3 = D.1590_2 * 4;
D.1592_5 = A_4(D) + D.1591_3;
D.1589_6 = *D.1592_5;
return D.1589_6;
The D.1592_5 line is a POINTER_PLUS_EXPR, which is turned into a getelementptr
on a bitcast of A_4 to i8*, so this becomes exactly the kind of IR that the
transform fires on.
An analogous transform (with no testcases!) already existed for bitcasts of
arrays, so I rewrote it to share code with this one.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@166474 91177308-0d34-0410-b5e6-96231b3b80d8
every TU where it's implicitly instantiated, even if there's an implicit
instantiation for the same types available in another TU.
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deterministic, replace it with a DenseMap<std::pair<unsigned, unsigned>,
PHINode*> (we already have a map from BasicBlock to unsigned).
<rdar://problem/12541389>
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