make it more consistent with its intended semantics.
The `linker_private_weak_def_auto' linkage type was meant to automatically hide
globals which never had their addresses taken. It has nothing to do with the
`linker_private' linkage type, which outputs the symbols with a `l' (ell) prefix
among other things.
The intended semantic is more like the `linkonce_odr' linkage type.
Change the name of the linkage type to `linkonce_odr_auto_hide'. And therefore
changing the semantics so that it produces the correct output for the linker.
Note: The old linkage name `linker_private_weak_def_auto' will still parse but
is not a synonym for `linkonce_odr_auto_hide'. This should be removed in 4.0.
<rdar://problem/11754934>
llvm-svn: 162114
multiple edges between two blocks is linear. If the caller is iterating all
edges leaving a BB that would be a square time algorithm. It is more efficient
to have the callers handle that case.
Currently the only callers are:
* GVN: already avoids the multiple edge case.
* Verifier: could only hit this assert when looking at an invalid invoke. Since
it already rejects the invoke, just avoid computing the dominance for it.
llvm-svn: 162113
where some fact lake a=b dominates a use in a phi, but doesn't dominate the
basic block itself.
This feature could also be implemented by splitting critical edges, but at least
with the current algorithm reasoning about the dominance directly is faster.
The time for running "opt -O2" in the testcase in pr10584 is 1.003 times slower
and on gcc as a single file it is 1.0007 times faster.
llvm-svn: 162023
This new attribute is intended to be used by the backend to determine how
the inline asm string should be parsed/printed. This patch adds the
ia_nsdialect attribute and also adds a test case to ensure the IR is
correctly parsed, but there is no functional change at this time.
The standard dialect is assumed to be AT&T. Therefore, this attribute
should only be added to MS-style inline assembly statements, which use
the Intel dialect. If we ever support more dialects we'll need to
add additional state to the attribute.
llvm-svn: 161641
a use or a BB, but it is inline in the handling of the invoke instruction.
This patch refactors it so that it can be used in other cases. For example, in
define i32 @f(i32 %x) {
bb0:
%cmp = icmp eq i32 %x, 0
br i1 %cmp, label %bb2, label %bb1
bb1:
br label %bb2
bb2:
%cond = phi i32 [ %x, %bb0 ], [ 0, %bb1 ]
%foo = add i32 %cond, %x
ret i32 %foo
}
GVN should be able to replace %x with 0 in any use that is dominated by the
true edge out of bb0. In the above example the only such use is the one in
the phi.
llvm-svn: 161429
The "findUsedStructTypes" method is very expensive to run. It needs to be
optimized so that LTO can run faster. Splitting this method out of the Module
class will help this occur. For instance, it can keep a list of seen objects so
that it doesn't process them over and over again.
llvm-svn: 161228
CI's name, and then used the StringRef pointing at its old name. I'm
fixing it by storing the name in a std::string, and hoisting the
renaming logic to happen always. This is nicer anyways as it will allow
the upgraded IR to have the same names as the input IR in more cases.
Another bug found by AddressSanitizer. Woot.
llvm-svn: 160572
intrinsics. The second instruction(s) to be handled are the vector versions
of count set bits (ctpop).
The changes here are to clang so that it generates a target independent
vector ctpop when it sees an ARM dependent vector bits set count. The changes
in llvm are to match the target independent vector ctpop and in
VMCore/AutoUpgrade.cpp to update any existing bc files containing ARM
dependent vector pop counts with target-independent ctpops. There are also
changes to an existing test case in llvm for ARM vector count instructions and
to a test for the bitcode upgrade.
<rdar://problem/11892519>
There is deliberately no test for the change to clang, as so far as I know, no
consensus has been reached regarding how to test neon instructions in clang;
q.v. <rdar://problem/8762292>
llvm-svn: 160410
intrinsics with target-indepdent intrinsics. The first instruction(s) to be
handled are the vector versions of count leading zeros (ctlz).
The changes here are to clang so that it generates a target independent
vector ctlz when it sees an ARM dependent vector ctlz. The changes in llvm
are to match the target independent vector ctlz and in VMCore/AutoUpgrade.cpp
to update any existing bc files containing ARM dependent vector ctlzs with
target-independent ctlzs. There are also changes to an existing test case in
llvm for ARM vector count instructions and a new test for the bitcode upgrade.
<rdar://problem/11831778>
There is deliberately no test for the change to clang, as so far as I know, no
consensus has been reached regarding how to test neon instructions in clang;
q.v. <rdar://problem/8762292>
llvm-svn: 160200
This was always part of the VMCore library out of necessity -- it deals
entirely in the IR. The .cpp file in fact was already part of the VMCore
library. This is just a mechanical move.
I've tried to go through and re-apply the coding standard's preferred
header sort, but at 40-ish files, I may have gotten some wrong. Please
let me know if so.
I'll be committing the corresponding updates to Clang and Polly, and
Duncan has DragonEgg.
Thanks to Bill and Eric for giving the green light for this bit of cleanup.
llvm-svn: 159421
Maintaining this kind of checking in different places is dangerous, extending
Instruction::isSameOperationAs consolidates this logic into one place. Here
I've added an optional flags parameter and two flags that are important for
vectorization: CompareIgnoringAlignment and CompareUsingScalarTypes.
llvm-svn: 159329
include/llvm/Analysis/DebugInfo.h to include/llvm/DebugInfo.h.
The reasoning is because the DebugInfo module is simply an interface to the
debug info MDNodes and has nothing to do with analysis.
llvm-svn: 159312
- simplifycfg: invoke undef/null -> unreachable
- instcombine: invoke new -> invoke expect(0, 0) (an arbitrary NOOP intrinsic; only done if the allocated memory is unused, of course)
- verifier: allow invoke of intrinsics (to make the previous step work)
llvm-svn: 159146
This allows the user/front-end to specify a model that is better
than what LLVM would choose by default. For example, a variable
might be declared as
@x = thread_local(initialexec) global i32 42
if it will not be used in a shared library that is dlopen'ed.
If the specified model isn't supported by the target, or if LLVM can
make a better choice, a different model may be used.
llvm-svn: 159077
Original message:
Performance optimizations:
- SwitchInst: case values stored separately from Operands List. It allows to make faster access to individual case value numbers or ranges.
- Optimized IntItem, added APInt value caching.
- Optimized IntegersSubsetGeneric: added optimizations for cases when subset is single number or when subset consists from single numbers only.
llvm-svn: 158997
fail. Original commit message:
Performance optimizations:
- SwitchInst: case values stored separately from Operands List. It allows to make faster access to individual case value numbers or ranges.
- Optimized IntItem, added APInt value caching.
- Optimized IntegersSubsetGeneric: added optimizations for cases when subset is single number or when subset consists from single numbers only.
On my machine these optimizations gave about 4-6% of compile-time improvement.
llvm-svn: 158986
- SwitchInst: case values stored separately from Operands List. It allows to make faster access to individual case value numbers or ranges.
- Optimized IntItem, added APInt value caching.
- Optimized IntegersSubsetGeneric: added optimizations for cases when subset is single number or when subset consists from single numbers only.
On my machine these optimizations gave about 4-6% of compile-time improvement.
llvm-svn: 158979
Original commit msg:
add the 'alloc' metadata node to represent the size of offset of buffers pointed to by pointers.
This metadata can be attached to any instruction returning a pointer
llvm-svn: 158688
since then the entire expression must equal zero (similarly for other operations
with an absorbing element). With this in place a bunch of reassociate code for
handling constants is dead since it is all taken care of when linearizing. No
intended functionality change.
llvm-svn: 158398
topologies, it is quite possible for a leaf node to have huge multiplicity, for
example: x0 = x*x, x1 = x0*x0, x2 = x1*x1, ... rapidly gives a value which is x
raised to a vast power (the multiplicity, or weight, of x). This patch fixes
the computation of weights by correctly computing them no matter how big they
are, rather than just overflowing and getting a wrong value. It turns out that
the weight for a value never needs more bits to represent than the value itself,
so it is enough to represent weights as APInts of the same bitwidth and do the
right overflow-avoiding dance steps when computing weights. As a side-effect it
reduces the number of multiplies needed in some cases of large powers. While
there, in view of external uses (eg by the vectorizer) I made LinearizeExprTree
static, pushing the rank computation out into users. This is progress towards
fixing PR13021.
llvm-svn: 158358
This removes a bit of context from the verifier erros, but reduces code
duplication in a fairly critical part of LLVM and makes dominates easier to test.
llvm-svn: 157845
IntItem cleanup. IntItemBase, IntItemConstantIntImp and IntItem merged into IntItem. All arithmetic operators was propogated from APInt. Also added comparison operators <,>,<=,>=. Currently you will find set of macros that propogates operators from APInt to IntItem in the beginning of IntegerSubset. Note that THESE MACROS WILL REMOVED after all passes will case-ranges compatible. Also note that these macros much smaller pain that something like this:
if (V->getValue().ugt(AnotherV->getValue()) { ... }
These changes made IntItem full featured integer object. It allows to make IntegerSubset class generic (move out all ConstantInt references inside and add unit-tests) in next commits.
llvm-svn: 157810
be non contiguous, non overlapping and sorted by the lower end.
While this is technically a backward incompatibility, every frontent currently
produces range metadata with a single interval and we don't have any pass
that merges intervals yet, so no existing bitcode files should be rejected by
this.
llvm-svn: 157741
Implemented IntItem - the wrapper around APInt. Why not to use APInt item directly right now?
1. It will very difficult to implement case ranges as series of small patches. We got several large and heavy patches. Each patch will about 90-120 kb. If you replace ConstantInt with APInt in SwitchInst you will need to changes at the same time all Readers,Writers and absolutely all passes that uses SwitchInst.
2. We can implement APInt pool inside and save memory space. E.g. we use several switches that works with 256 bit items (switch on signatures, or strings). We can avoid value duplicates in this case.
3. IntItem can be easyly easily replaced with APInt.
4. Currenly we can interpret IntItem both as ConstantInt and as APInt. It allows to provide SwitchInst methods that works with ConstantInt for non-updated passes.
Why I need it right now? Currently I need to update SimplifyCFG pass (EqualityComparisons). I need to work with APInts directly a lot, so peaces of code
ConstantInt *V = ...;
if (V->getValue().ugt(AnotherV->getValue()) {
...
}
will look awful. Much more better this way:
IntItem V = ConstantIntVal->getValue();
if (AnotherV < V) {
}
Of course any reviews are welcome.
P.S.: I'm also going to rename ConstantRangesSet to IntegersSubset, and CRSBuilder to IntegersSubsetMapping (allows to map individual subsets of integers to the BasicBlocks).
Since in future these classes will founded on APInt, it will possible to use them in more generic ways.
llvm-svn: 157576
making it stronger and more sane.
Delete the code from tblgen that produced the old code.
Besides being a path forward in intrinsic sanity, this also eliminates a bunch of
machine generated code that was compiled into Function.o
llvm-svn: 157545
separate side table, using the handy SequenceToOffsetTable class. This encodes all
these weird things into another 256 bytes, allowing all intrinsics to be encoded this way.
llvm-svn: 156995
generated code (for Intrinsic::getType) into a table. This handles common cases right now,
but I plan to extend it to handle all cases and merge in type verification logic as well
in follow-on patches.
llvm-svn: 156905
Ordinary patch for PR1255.
Added new case-ranges orientated methods for adding/removing cases in SwitchInst. After this patch cases will internally representated as ConstantArray-s instead of ConstantInt, externally cases wrapped within the ConstantRangesSet object.
Old methods of SwitchInst are also works well, but marked as deprecated. So on this stage we have no side effects except that I added support for case ranges in BitcodeReader/Writer, of course test for Bitcode is also added. Old "switch" format is also supported.
llvm-svn: 156704
Instruction::IsIdenticalToWhenDefined.
This manifested itself when inlining two calls to the same function. The
inlined function had a switch statement that returned one of a set of
global variables. Without this modification, the two phi instructions that
chose values from the branches of the switch instruction inlined from the
callee were considered equivalent and jump-threading replaced a load for the
first switch value with a phi selecting from the second switch, thereby
producing incorrect code.
This patch has been tested with "make check-all", "lnt runteste nt", and
llvm self-hosted, and on the original program that had this problem,
wireshark.
<rdar://problem/11025519>
llvm-svn: 156548
This lets you save the textual representation of the LLVM IR to a file.
Before this patch it could only be printed to STDERR from llvm-c.
Patch by Carlo Kok!
llvm-svn: 156479
Added new case-ranges orientated methods for adding/removing cases in SwitchInst. After this patch cases will internally representated as ConstantArray-s instead of ConstantInt, externally cases wrapped within the ConstantRangesSet object.
Old methods of SwitchInst are also works well, but marked as deprecated. So on this stage we have no side effects except that I added support for case ranges in BitcodeReader/Writer, of course test for Bitcode is also added. Old "switch" format is also supported.
llvm-svn: 156374
instead of getAggregateElement. This has the advantage of being
more consistent and allowing higher-level constant folding to
procede even if an inner extract element cannot be folded.
Make ConstantFoldInstruction call ConstantFoldConstantExpression
on the instruction's operands, making it more consistent with
ConstantFoldConstantExpression itself. This makes sure that
ConstantExprs get TargetData-aware folding before being handed
off as operands for further folding.
This causes more expressions to be folded, but due to a known
shortcoming in constant folding, this currently has the side effect
of stripping a few more nuw and inbounds flags in the non-targetdata
side of constant-fold-gep.ll. This is mostly harmless.
This fixes rdar://11324230.
llvm-svn: 155682
through the use of 'fpmath' metadata. Currently this only provides a 'fpaccuracy'
value, which may be a number in ULPs or the keyword 'fast', however the intent is
that this will be extended with additional information about NaN's, infinities
etc later. No optimizations have been hooked up to this so far.
llvm-svn: 154822
thinking of generalizing it to be able to specify other freedoms beyond accuracy
(such as that NaN's don't have to be respected). I'd like the 3.1 release (the
first one with this metadata) to have the more generic name already rather than
having to auto-upgrade it in 3.2.
llvm-svn: 154744
directly instead of a user Instruction. This allows them to test
whether a def dominates a particular operand if the user instruction
is a PHI.
llvm-svn: 154631
FoldingSet is implemented as a chained hash table. When there is a hash
collision during insertion, which is common as we fill the table until a
load factor of 2.0 is hit, we walk the chained elements, comparing every
operand with the new element's operands. This can be very expensive if the
MDNode has many operands.
We sacrifice a word of space in MDNode to cache the full hash value, reducing
compares on collision to a minimum. MDNode grows from 28 to 32 bytes + operands
on x86. On x86_64 the new bits fit nicely into existing padding, not growing
the struct at all.
The actual speedup depends a lot on the test case and is typically between
1% and 2% for C++ code with clang -c -O0 -g.
llvm-svn: 154497
StringMap. This was redundant and unnecessarily bloated the MDString class.
Because the MDString class is a "Value" and will never have a "name", and
because the Name field in the Value class is a pointer to a StringMap entry, we
repurpose the Name field for an MDString. It stores the StringMap entry in the
Name field, and uses the normal methods to get the string (name) back.
PR12474
llvm-svn: 154429
An MDNode has a list of MDNodeOperands allocated directly after it as part of
its allocation. Therefore, the Parent of the MDNodeOperands can be found by
walking back through the operands to the beginning of that list. Mark the first
operand's value pointer as being the 'first' operand so that we know where the
beginning of said list is.
This saves a *lot* of space during LTO with -O0 -g flags.
llvm-svn: 154280
correlated pairs of pointer arguments at the callsite. This is designed
to recognize the common C++ idiom of begin/end pointer pairs when the
end pointer is a constant offset from the begin pointer. With the
C-based idiom of a pointer and size, the inline cost saw the constant
size calculation, and this provides the same level of information for
begin/end pairs.
In order to propagate this information we have to search for candidate
operations on a pair of pointer function arguments (or derived from
them) which would be simplified if the pointers had a known constant
offset. Then the callsite analysis looks for such pointer pairs in the
argument list, and applies the appropriate bonus.
This helps LLVM detect that half of bounds-checked STL algorithms
(such as hash_combine_range, and some hybrid sort implementations)
disappear when inlined with a constant size input. However, it's not
a complete fix due the inaccuracy of our cost metric for constants in
general. I'm looking into that next.
Benchmarks showed no significant code size change, and very minor
performance changes. However, specific code such as hashing is showing
significantly cleaner inlining decisions.
llvm-svn: 152752
Renamed methods caseBegin, caseEnd and caseDefault with case_begin, case_end, and case_default.
Added some notes relative to case iterators.
llvm-svn: 152532
a common collection of methods on Value, and share their implementation.
We had two variations in two different places already, and I need the
third variation for inline cost estimation.
Reviewed by Duncan Sands on IRC, but further comments here welcome.
llvm-svn: 152490
http://lists.cs.uiuc.edu/pipermail/llvm-commits/Week-of-Mon-20120130/136146.html
Implemented CaseIterator and it solves almost all described issues: we don't need to mix operand/case/successor indexing anymore. Base iterator class is implemented as a template since it may be initialized either from "const SwitchInst*" or from "SwitchInst*".
ConstCaseIt is just a read-only iterator.
CaseIt is read-write iterator; it allows to change case successor and case value.
Usage of iterator allows totally remove resolveXXXX methods. All indexing convertions done automatically inside the iterator's getters.
Main way of iterator usage looks like this:
SwitchInst *SI = ... // intialize it somehow
for (SwitchInst::CaseIt i = SI->caseBegin(), e = SI->caseEnd(); i != e; ++i) {
BasicBlock *BB = i.getCaseSuccessor();
ConstantInt *V = i.getCaseValue();
// Do something.
}
If you want to convert case number to TerminatorInst successor index, just use getSuccessorIndex iterator's method.
If you want initialize iterator from TerminatorInst successor index, use CaseIt::fromSuccessorIndex(...) method.
There are also related changes in llvm-clients: klee and clang.
llvm-svn: 152297
to hash_combine. One of the interfaces could already do this, and the
other can just use a small buffer. This is a much more efficient way to
use the hash_combine interface, although I don't have any particular
benchmark where this code was hot, so I can't measure much of an impact.
It at least doesn't slow anything down.
llvm-svn: 152200
"is sized". This prevents every query to isSized() from recursing over
every sub-type of a struct type. This could get *very* slow for
extremely deep nesting of structs, as in 177.mesa.
This change is a 45% speedup for 'opt -O2' of 177.mesa.linked.bc, and
likely a significant speedup for other cases as well. It even impacts
-O0 cases because so many part of the code try to check whether a type
is sized.
Thanks for the review from Nick Lewycky and Benjamin Kramer on IRC.
llvm-svn: 152197
new hash_value infrastructure, and replace their implementations using
hash_combine. This removes a complete copy of Jenkin's lookup3 hash
function (which is both significantly slower and lower quality than the
one implemented in hash_combine) along with a somewhat scary xor-only
hash function.
Now that APInt and APFloat can be passed directly to hash_combine,
simplify the rest of the LLVMContextImpl hashing to use the new
infrastructure.
llvm-svn: 152004
of the proposed standard hashing interfaces (N3333), and to use
a modified and tuned version of the CityHash algorithm.
Some of the highlights of this change:
-- Significantly higher quality hashing algorithm with very well
distributed results, and extremely few collisions. Should be close to
a checksum for up to 64-bit keys. Very little clustering or clumping of
hash codes, to better distribute load on probed hash tables.
-- Built-in support for reserved values.
-- Simplified API that composes cleanly with other C++ idioms and APIs.
-- Better scaling performance as keys grow. This is the fastest
algorithm I've found and measured for moderately sized keys (such as
show up in some of the uniquing and folding use cases)
-- Support for enabling per-execution seeds to prevent table ordering
or other artifacts of hashing algorithms to impact the output of
LLVM. The seeding would make each run different and highlight these
problems during bootstrap.
This implementation was tested extensively using the SMHasher test
suite, and pased with flying colors, doing better than the original
CityHash algorithm even.
I've included a unittest, although it is somewhat minimal at the moment.
I've also added (or refactored into the proper location) type traits
necessary to implement this, and converted users of GeneralHash over.
My only immediate concerns with this implementation is the performance
of hashing small keys. I've already started working to improve this, and
will continue to do so. Currently, the only algorithms faster produce
lower quality results, but it is likely there is a better compromise
than the current one.
Many thanks to Jeffrey Yasskin who did most of the work on the N3333
paper, pair-programmed some of this code, and reviewed much of it. Many
thanks also go to Geoff Pike Pike and Jyrki Alakuijala, the original
authors of CityHash on which this is heavily based, and Austin Appleby
who created MurmurHash and the SMHasher test suite.
Also thanks to Nadav, Tobias, Howard, Jay, Nick, Ahmed, and Duncan for
all of the review comments! If there are further comments or concerns,
please let me know and I'll jump on 'em.
llvm-svn: 151822
verifier does. This correctly handles invoke.
Thanks to Duncan, Andrew and Chris for the comments.
Thanks to Joerg for the early testing.
llvm-svn: 151469
Chad Rosier