Summary:
RelocVisitor had too many, too small functions. This patch group them
by architecture rather than each relocation type.
Reviewers: grimar, dblaikie
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D33580
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@303950 91177308-0d34-0410-b5e6-96231b3b80d8
We do not track liveness of reserved registers so adding them to the
liveins list in computeLiveIns() was completely unnecessary.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@303937 91177308-0d34-0410-b5e6-96231b3b80d8
Merging two type streams is one of the most time consuming
parts of generating a PDB, and as such it needs to be as
fast as possible. The visitor abstractions used for interoperating
nicely with many different types of inputs and outputs have
been used widely and help greatly for testability and implementing
tools, but the abstractions build up and get in the way of
performance.
This patch removes all of the visitation stuff from the type
stream merger, essentially re-inventing the leaf / member switch
and loop, but at a very low level. This allows us many other
optimizations, such as not actually deserializing *any* records
(even member records which don't describe their own length), as
the operation of "figure out how long this record is" is somewhat
faster than "figure out how long this record *and* get all its
fields out". Furthermore, whereas before we had to deserialize,
re-write type indices, then re-serialize, now we don't have to
do any of those 3 steps. We just find out where the type indices
are and pull them directly out of the byte stream and re-write
them.
This is worth a 50-60% performance increase. On top of all other
optimizations that have been applied this week, I now get the
following numbers when linking lld.exe and lld.pdb
MSVC: 25.67s
Before This Patch: 18.59s
After This Patch: 8.92s
So this is a huge performance win.
Differential Revision: https://reviews.llvm.org/D33564
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@303935 91177308-0d34-0410-b5e6-96231b3b80d8
Right now scalarpre doesn't have phi-translate support, so it will miss some
simple pre opportunities. Like the following testcase, current scalarpre cannot
recognize the last "a * b" is fully redundent because a and b used by the last
"a * b" expr are both defined by phis.
long a[100], b[100], g1, g2, g3;
__attribute__((pure)) long goo();
void foo(long a, long b, long c, long d) {
g1 = a * b;
if (__builtin_expect(g2 > 3, 0)) {
a = c;
b = d;
g2 = a * b;
}
g3 = a * b; // fully redundant.
}
The patch adds phi-translate support in scalarpre. This is only a temporary
solution before the newpre based on newgvn is available.
Differential Revision: https://reviews.llvm.org/D32252
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@303923 91177308-0d34-0410-b5e6-96231b3b80d8
Originally this was intended to be set up so that when linking
a PDB which refers to a type server, it would only visit the
PDB once, and on subsequent visitations it would just skip it
since all the records had already been added.
Due to some C++ scoping issues, this was not occurring and it
was revisiting the type server every time, which caused every
record to end up being thrown away on all subsequent visitations.
This doesn't affect the performance of linking clang-cl generated
object files because we don't use type servers, but when linking
object files and libraries generated with /Zi via MSVC, this means
only 1 object file has to be linked instead of N object files, so
the speedup is quite large.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@303920 91177308-0d34-0410-b5e6-96231b3b80d8
Previously, every time we wanted to serialize a field list record, we
would create a new copy of FieldListRecordBuilder, which would in turn
create a temporary instance of TypeSerializer, which itself had a
std::vector<> that was about 128K in size. So this 128K allocation was
happening every time. We can re-use the same instance over and over, we
just have to clear its internal hash table and seen records list between
each run. This saves us from the constant re-allocations.
This is worth an ~18.5% speed increase (3.75s -> 3.05s) in my tests.
Differential Revision: https://reviews.llvm.org/D33506
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@303919 91177308-0d34-0410-b5e6-96231b3b80d8
Summary:
DbiStreamBuilder calculated the offset of the source file names inside
the file info substream as the size of the file info substream minus
the size of the file names. Since the file info substream is padded to
a multiple of 4 bytes, this caused the first file name to be aligned
on a 4-byte boundary. By contrast, DbiModuleList would read the file
names immediately after the file name offset table, without skipping
to the next 4-byte boundary. This change makes it so that the file
names are written to the location where DbiModuleList expects them,
and puts any necessary padding for the file info substream after the
file names instead of before it.
Reviewers: amccarth, rnk, zturner
Reviewed By: amccarth, zturner
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D33475
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@303917 91177308-0d34-0410-b5e6-96231b3b80d8
It was using the number of blocks of the entire PDB file as the number
of blocks of each stream that was created. This was only an issue in
the readLongestContiguousChunk function, which was never called prior.
This bug surfaced when I updated an algorithm to use this function and
the algorithm broke.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@303916 91177308-0d34-0410-b5e6-96231b3b80d8
A profile shows the majority of time doing type merging is spent
deserializing records from sequences of bytes into friendly C++ structures
that we can easily access members of in order to find the type indices to
re-write.
Records are prefixed with their length, however, and most records have
type indices that appear at fixed offsets in the record. For these
records, we can save some cycles by just looking at the right place in the
byte sequence and re-writing the value, then skipping the record in the
type stream. This saves us from the costly deserialization of examining
every field, including potentially null terminated strings which are the
slowest, even though it was unnecessary to begin with.
In addition, we apply another optimization. Previously, after
deserializing a record and re-writing its type indices, we would
unconditionally re-serialize it in order to compute the hash of the
re-written record. This would result in an alloc and memcpy for every
record. If no type indices were re-written, however, this was an
unnecessary allocation. In this patch re-writing is made two phase. The
first phase discovers the indices that need to be rewritten and their new
values. This information is passed through to the de-duplication code,
which only copies and re-writes type indices in the serialized byte
sequence if at least one type index is different.
Some records have type indices which only appear after variable length
strings, or which have lists of type indices, or various other situations
that can make it tricky to make this optimization. While I'm not giving up
on optimizing these cases as well, for now we can get the easy cases out
of the way and lay the groundwork for more complicated cases later.
This patch yields another 50% speedup on top of the already large speedups
submitted over the past 2 days. In two tests I have run, I went from 9
seconds to 3 seconds, and from 16 seconds to 8 seconds.
Differential Revision: https://reviews.llvm.org/D33480
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@303914 91177308-0d34-0410-b5e6-96231b3b80d8
This patch provides an initial prototype for a pass that sinks instructions based on GVN information, similar to GVNHoist. It is not yet ready for commiting but I've uploaded it to gather some initial thoughts.
This pass attempts to sink instructions into successors, reducing static
instruction count and enabling if-conversion.
We use a variant of global value numbering to decide what can be sunk.
Consider:
[ %a1 = add i32 %b, 1 ] [ %c1 = add i32 %d, 1 ]
[ %a2 = xor i32 %a1, 1 ] [ %c2 = xor i32 %c1, 1 ]
\ /
[ %e = phi i32 %a2, %c2 ]
[ add i32 %e, 4 ]
GVN would number %a1 and %c1 differently because they compute different
results - the VN of an instruction is a function of its opcode and the
transitive closure of its operands. This is the key property for hoisting
and CSE.
What we want when sinking however is for a numbering that is a function of
the *uses* of an instruction, which allows us to answer the question "if I
replace %a1 with %c1, will it contribute in an equivalent way to all
successive instructions?". The (new) PostValueTable class in GVN provides this
mapping.
This pass has some shown really impressive improvements especially for codesize already on internal benchmarks, so I have high hopes it can replace all the sinking logic in SimplifyCFG.
Differential revision: https://reviews.llvm.org/D24805
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@303850 91177308-0d34-0410-b5e6-96231b3b80d8
If Op is equal to array_lengthof, the lookup would be out of bounds, but we were only checking for greater than. I suspect nothing ever passes in the equal value because its a sentinel to mark the end of the builtin opcodes and not a real opcode.
So really this fix is just so that the code looks right and makes sense.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@303840 91177308-0d34-0410-b5e6-96231b3b80d8
having it internally allocate the loop.
This is a much more flexible API and necessary in the new loop unswitch
to reasonably support both new and old PMs in common code. It also just
seems like a cleaner separation of concerns.
NFC, this should just be a pure refactoring.
Differential Revision: https://reviews.llvm.org/D33528
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@303834 91177308-0d34-0410-b5e6-96231b3b80d8
This change allows llvm-nm to print symbols found in import libraries,
in part by allowing COFFImportFiles to be casted to SymbolicFiles.
Patch by Dave Lee!
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@303821 91177308-0d34-0410-b5e6-96231b3b80d8
The loop vectorizer usually vectorizes any instruction it can and then
extracts the elements for a scalarized use. On SystemZ, all elements
containing addresses must be extracted into address registers (GRs). Since
this extraction is not free, it is better to have the address in a suitable
register to begin with. By forcing address arithmetic instructions and loads
of addresses to be scalar after vectorization, two benefits result:
* No need to extract the register
* LSR optimizations trigger (LSR isn't handling vector addresses currently)
Benchmarking show improvements on SystemZ with this new behaviour.
Any other target could try this by returning false in the new hook
prefersVectorizedAddressing().
Review: Renato Golin, Elena Demikhovsky, Ulrich Weigand
https://reviews.llvm.org/D32422
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@303744 91177308-0d34-0410-b5e6-96231b3b80d8
When folding arguments of AddExpr or MulExpr with recurrences, we rely on the fact that
the loop of our base recurrency is the bottom-lost in terms of domination. This assumption
may be broken by an expression which is treated as invariant, and which depends on a complex
Phi for which SCEVUnknown was created. If such Phi is a loop Phi, and this loop is lower than
the chosen AddRecExpr's loop, it is invalid to fold our expression with the recurrence.
Another reason why it might be invalid to fold SCEVUnknown into Phi start value is that unlike
other SCEVs, SCEVUnknown are sometimes position-bound. For example, here:
for (...) { // loop
phi = {A,+,B}
}
X = load ...
Folding phi + X into {A+X,+,B}<loop> actually makes no sense, because X does not exist and cannot
exist while we are iterating in loop (this memory can be even not allocated and not filled by this moment).
It is only valid to make such folding if X is defined before the loop. In this case the recurrence {A+X,+,B}<loop>
may be existant.
This patch prohibits folding of SCEVUnknown (and those who use them) into the start value of an AddRecExpr,
if this instruction is dominated by the loop. Merging the dominating unknown values is still valid. Some tests that
relied on the fact that some SCEVUnknown should be folded into AddRec's are changed so that they no longer
expect such behavior.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@303730 91177308-0d34-0410-b5e6-96231b3b80d8
LazyRandomTypeCollection is designed for random access, and in
order to provide this it lazily indexes ranges of types. In the
case of types from an object file, there is no partial index
to build off of, so it has to index the full stream up front.
However, merging types only requires sequential access, and when
that is needed, this extra work is simply wasted. Changing the
algorithm to work on sequential arrays of types rather than
random access type collections eliminates this up front scan.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@303707 91177308-0d34-0410-b5e6-96231b3b80d8
When writing field list records, we would construct a temporary
type serializer that shared a bump ptr allocator with the rest
of the application, so anything allocated from here would live
forever. Furthermore, this temporary serializer had all the
properties of a full blown serializer including record hashing
and de-duplication.
These features are required when you're merging multiple type
streams into each other, because different streams may contain
identical records, but records from the same type stream will
never collide with each other. So all of this hashing was
unnecessary.
To solve this, two fixes are made:
1) The temporary serializer keeps its own bump ptr allocator
instead of sharing a global one. When it's finished, all of
its memory is freed.
2) Instead of using the same temporary serializer for the life
of an entire type stream, we use it only for the life of a single
field list record and delete it when the field list record is
completed. This way the hash table will not grow as other
records from the same type stream get inserted. Further improvements
could eliminate hashing entirely from this codepath.
This reduces the link time by 85% in my test, from 1 minute to 9
seconds.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@303676 91177308-0d34-0410-b5e6-96231b3b80d8
Summary:
This is a first patch for GSoC project, bash-completion for clang.
To use this on bash, please run `source clang/utils/bash-autocomplete.sh`.
bash-autocomplete.sh is code for bash-completion.
Simple flag completion and path completion is available in this patch.
Reviewers: teemperor, v.g.vassilev, ruiu, Bigcheese, efriedma
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D33237
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@303670 91177308-0d34-0410-b5e6-96231b3b80d8
Summary:
First, StringMap uses llvm::HashString, which is only good for short
identifiers and really bad for large blobs of binary data like type
records. Moving to `DenseMap<StringRef, TypeIndex>` with some tricks for
memory allocation fixes that.
Unfortunately, that didn't buy very much performance. Profiling showed
that we spend a long time during DenseMap growth rehashing existing
entries. Also, in general, DenseMap is faster when the keys are small.
This change takes that to the logical conclusion by introducing a small
wrapper value type around a pointer to key data. The key data contains a
precomputed hash, the original record data (pointer and size), and the
type index, which is the "value" of our original map.
This reduces the time to produce llvm-as.exe and llvm-as.pdb from ~15s
on my machine to 3.5s, which is about a 4x improvement.
Reviewers: zturner, inglorion, ruiu
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D33428
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@303665 91177308-0d34-0410-b5e6-96231b3b80d8
Summary:
Before this change, AttributeLists stored a pair of index and
AttributeSet. This is memory efficient if most arguments do not have
attributes. However, it requires doing a search over the pairs to test
an argument or function attribute. Profiling shows that this loop was
0.76% of the time in 'opt -O2' of sqlite3.c, because LLVM constantly
tests values for nullability.
This was worth about 2.5% of mid-level optimization cycles on the
sqlite3 amalgamation. Here are the full perf results:
https://reviews.llvm.org/P7995
Here are just the before and after cycle counts:
```
$ perf stat -r 5 ./opt_before -O2 sqlite3.bc -o /dev/null
13,274,181,184 cycles # 3.047 GHz ( +- 0.28% )
$ perf stat -r 5 ./opt_after -O2 sqlite3.bc -o /dev/null
12,906,927,263 cycles # 3.043 GHz ( +- 0.51% )
```
This patch *does not* change the indices used to query attributes, as
requested by reviewers. Tracking whether an index is usable for array
indexing is a huge pain that affects many of the internal APIs, so it
would be good to come back later and do a cleanup to remove this
internal adjustment.
Reviewers: pete, chandlerc
Subscribers: javed.absar, llvm-commits
Differential Revision: https://reviews.llvm.org/D32819
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@303654 91177308-0d34-0410-b5e6-96231b3b80d8
This reverts commit e34ccb7b57da25cc89ded913d8638a2906d1110a.
This is causing failures on the ASAN bots.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@303640 91177308-0d34-0410-b5e6-96231b3b80d8
This patch builds over https://reviews.llvm.org/rL303349 and replaces
the use of the condition only if it is safe to do so.
We should not blindly RAUW the condition if experimental.guard or assume
is a use of that
condition. This is because LVI may have used the guard/assume to
identify the
value of the condition, and RUAWing will fold the guard/assume and uses
before the guards/assumes.
Reviewers: sanjoy, reames, trentxintong, mkazantsev
Reviewed by: sanjoy, reames
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D33257
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@303633 91177308-0d34-0410-b5e6-96231b3b80d8
Summary:
Add Max ModFlagBehavior, which can be used to take the max of two
module flag values when merging modules. Use it for the PIE and PIC
levels.
This avoids an error when we try to import from a module built -fpic
into a module built -fPIC, for example. For both PIE and PIC levels,
this will be legal, since the code generation gets more conservative
as the level is increased. Therefore we can take the max instead of
somehow trying to block importing between modules compiled with
different levels.
Reviewers: tmsriram, pcc
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D33418
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@303590 91177308-0d34-0410-b5e6-96231b3b80d8
The forward declarations and the SimplifyQuery class at the beginning of the namespace weren't indented. But the closing brace for SimplifyQuery and everything after it were indented.
This commit makes the whole file consistent to no identation per coding standards. The signature of every function in this file changed a few weeks ago so this isn't a big disturbance to the revision history.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@303588 91177308-0d34-0410-b5e6-96231b3b80d8
Previous algotirhm assumed that types and ids are in a single
unified stream. For inputs that come from object files, this
is the case. But if the input is already a PDB, or is the result
of a previous merge, then the types and ids will already have
been split up, in which case we need an algorithm that can
accept operate on independent streams of types and ids that
refer across stream boundaries to each other.
Differential Revision: https://reviews.llvm.org/D33417
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@303577 91177308-0d34-0410-b5e6-96231b3b80d8
MachineInstructions that don't generate any code (such as
IMPLICIT_DEFs) should not generate any debug info either.
Fixes PR33107.
https://bugs.llvm.org/show_bug.cgi?id=33107
This reapplies r303566 without any modifications. The stage2 build
failures persisted even after reverting this patch, and looking back
through history, it looks like these tests are flaky.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@303575 91177308-0d34-0410-b5e6-96231b3b80d8
It's causing some buildbots to timeout whenever tablegen needs re-compilation,
particularly those with -fsanitize=memory but not only them. A compile time
regression was expected since it triples the amount of SelectionDAG rules we
are able to import but it's currently too high.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@303542 91177308-0d34-0410-b5e6-96231b3b80d8
Re-applying now that PR32825 which was raised on the commit this fixed up is now known to have also been fixed by this commit.
Original commit message:
Multiple ldr pseudoinstructions with the same constant value will
reuse the same constant pool entry. However, if the constant pool
is explicitly flushed with a .ltorg directive, we should not try
to reference constants in the previous pool any longer, since they
may be out of range.
This fixes assembling hand-written assembler source which repeatedly
loads the same constant value, across a binary size larger than the
pc-relative fixup range for ldr instructions (4096 bytes). Such
assembler source already uses explicit .ltorg instructions to emit
constant pools with regular intervals. However if we try to reuse
constants emitted in earlier pools, they end up out of range.
This makes the output of the testcase match what binutils gas does
(prior to this patch, it would fail to assemble).
Differential Revision: https://reviews.llvm.org/D32847
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@303540 91177308-0d34-0410-b5e6-96231b3b80d8
Re-applying now that the open bug on this commit, PR32825, is known to be fixed.
Original commit message:
Summary: This patch returns the same label if the CP entry with the same value has been created.
Reviewers: eli.friedman, rengolin, jmolloy
Subscribers: majnemer, jmolloy, llvm-commits
Differential Revision: https://reviews.llvm.org/D25804
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@303539 91177308-0d34-0410-b5e6-96231b3b80d8
This reverts commit r302416. This was a fixup for r286006, which has now been reverted so this doesn't apply (either in concept or in code).
This commit itself has no problems, but the underlying issue it was fixing has now disappeared from the codebase.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@303536 91177308-0d34-0410-b5e6-96231b3b80d8
llvm-symbolizer would fail to symbolize addresses in unlinked object
files when handling .dwo file data because the addresses would not be
relocated in the same way as the ranges in the skeleton CU in the object
file.
Fix that so object files can be symbolized the same as executables.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@303532 91177308-0d34-0410-b5e6-96231b3b80d8
This is a re-application of a r303497 that was reverted in r303498.
I thought it had broken a bot when it had not (the breakage did not
go away with the revert).
This change makes the split between the "exact" backedge taken count
and the "maximum" backedge taken count a bit more obvious. Both of
these are upper bounds on the number of times the loop header
executes (since SCEV does not account for most kinds of abnormal
control flow), but the latter is guaranteed to be a constant.
There were a few places where the max backedge taken count *was* a
non-constant; I've changed those to compute constants instead.
At this point, I'm not sure if the constant max backedge count can be
computed by calling `getUnsignedRange(Exact).getUnsignedMax()` without
losing precision. If it can, we can simplify even further by making
`getMaxBackedgeTakenCount` a thin wrapper around
`getBackedgeTakenCount` and `getUnsignedRange`.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@303531 91177308-0d34-0410-b5e6-96231b3b80d8
