Simon Pilgrim [Sat, 6 May 2017 17:30:39 +0000 (17:30 +0000)]
[X86][SSE] Break register dependencies on v16i8/v8i16 BUILD_VECTOR on SSE41
rL294581 broke unnecessary register dependencies on partial v16i8/v8i16 BUILD_VECTORs, but on SSE41 we (currently) use insertion for full BUILD_VECTORs as well. By allowing full insertion to occur on SSE41 targets we can break register dependencies here as well.
Brian Gesiak [Sat, 6 May 2017 16:22:53 +0000 (16:22 +0000)]
[Analysis] Print out unreachable loops
Summary:
When writing a loop pass I made a mistake and hit the assertion
"Unreachable block in loop". Later, I hit an assertion when I called
`BasicBlock::eraseFromParent()` incorrectly: "Use still stuck around
after Def is destroyed". This latter assertion, however, printed out
exactly which value is being deleted and what uses remain, which helped
me debug the issue.
To help people debugging their loop passes in the future, print out
exactly which basic block is unreachable in a loop.
Craig Topper [Sat, 6 May 2017 06:03:07 +0000 (06:03 +0000)]
[SCEV] Remove extra APInt copies from getRangeForAffineARHelper.
This changes one parameter to be a const APInt& since we only read from it. Use std::move on local APInts once they are no longer needed so we can reuse their allocations. Lastly, use operator+=(uint64_t) instead of adding 1 to an APInt twice creating a new APInt each time.
Craig Topper [Sat, 6 May 2017 03:35:15 +0000 (03:35 +0000)]
[LazyValueInfo] Avoid unnecessary copies of ConstantRanges
Summary:
ConstantRange contains two APInts which can allocate memory if their width is larger than 64-bits. So we shouldn't copy it when we can avoid it.
This changes LVILatticeVal::getConstantRange() to return its internal ConstantRange by reference. This allows many places that just need a ConstantRange reference to avoid making a copy.
Several places now capture the return value of getConstantRange() by reference so they can call methods on it that don't need a new object.
Lastly it adds std::move in one place to capture to move a local ConstantRange into an LVILatticeVal.
Craig Topper [Fri, 5 May 2017 22:46:40 +0000 (22:46 +0000)]
[BitVector] Improve the description of the BitVector::clear to say it removes the bits rather than clearing since clearing could be interpreted as just zeroing. NFC
Zachary Turner [Fri, 5 May 2017 22:02:37 +0000 (22:02 +0000)]
[CodeView] Reserve TypeDatabase records up front.
Most of the time we know exactly how many type records we
have in a list, and we want to use the visitor to deserialize
them into actual records in a database. Previously we were
just using push_back() every time without reserving the space
up front in the vector. This is obviously terrible from a
performance standpoint, and it's not uncommon to have PDB
files with half a million type records, where the performance
degredation was quite noticeable.
Matthias Braun [Fri, 5 May 2017 21:09:30 +0000 (21:09 +0000)]
MIParser/MIRPrinter: Compute block successors if not explicitely specified
- MIParser: If the successor list is not specified successors will be
added based on basic block operands in the block and possible
fallthrough.
- MIRPrinter: Adds a new `simplify-mir` option, with that option set:
Skip printing of block successor lists in cases where the
parser is guaranteed to reconstruct it. This means we still print the
list if some successor cannot be determined (happens for example for
jump tables), if the successor order changes or branch probabilities
being unequal.
Reid Kleckner [Fri, 5 May 2017 18:30:34 +0000 (18:30 +0000)]
Simplify dbg.value handling in SDISel with early returns
No functional change other than improving dbgs logging accuracy on
constant dbg values. Previously we would add things like "i32 42" as
debug values, and then log that we were dropping the debug info, which
is silly.
Delete some dead code that was checking for static allocas. This
remained after r207165, but served no purpose. Currently, static alloca
dbg.values are always sent through the DanglingDebugInfoMap, and are
usually made valid the first time the alloca is used.
Craig Topper [Fri, 5 May 2017 17:36:09 +0000 (17:36 +0000)]
[KnownBits] Add wrapper methods for setting and clear all bits in the underlying APInts in KnownBits.
This adds routines for reseting KnownBits to unknown, making the value all zeros or all ones. It also adds methods for querying if the value is zero, all ones or unknown.
Adrian McCarthy [Fri, 5 May 2017 17:14:00 +0000 (17:14 +0000)]
Allow operator-> to work from a FixedStreamArrayIterator.
This is similar to my recent fix for VarStreamArrayIterator, but the cause
(and thus the fix) is subtley different. The FixedStreamArrayIterator
iterates over a const Array, so the iterator's value type must be const.
Hoisting common code can cause registers that live-in in the successor
blocks to no longer be live-in. The live-in information needs to be
updated to reflect this, or otherwise incorrect code can be generated
later on.
John Brawn [Fri, 5 May 2017 11:31:25 +0000 (11:31 +0000)]
[ARM] Add support for ORR and ORN instruction substitutions
Recently support was added for substituting one intruction for another by
negating or inverting the immediate, but ORR and ORN were missed so this patch
adds them.
This one is slightly different to the others in that ORN only exists in thumb,
so we only do the substitution in thumb.
George Rimar [Fri, 5 May 2017 10:52:39 +0000 (10:52 +0000)]
[llvm-dwarfdump] - Print an error message if section decompression failed.
llvm-dwarfdump currently prints no message if decompression fails
for some reason. I noticed that during work on one of LLD patches
where LLD produced an broken output. It was a bit confusing to see
no output for section dumped and no any error message at all.
Zachary Turner [Thu, 4 May 2017 23:53:54 +0000 (23:53 +0000)]
[pdb] Don't verify TPI hash values up front.
Verifying the hash values as we are currently doing
results in iterating every type record before the user
even tries to access the first one, and the API user
has no control over, or ability to hook into this
process.
As a result, when the user wants to iterate over types
to print them or index them, this results in a second
iteration over the same list of types. When there's
upwards of 1,000,000 type records, this is obviously
quite undesirable.
This patch raises the verification outside of TpiStream
, and llvm-pdbdump hooks a hash verification visitor
into the normal dumping process. So we still verify
the hash records, but we can do it while not requiring
a second iteration over the type stream.
Zachary Turner [Thu, 4 May 2017 23:53:29 +0000 (23:53 +0000)]
[PDB] Don't build the entire source file list up front.
I tried to run llvm-pdbdump on a very large (~1.5GB) PDB to
try and identify show-stopping performance problems. This
patch addresses the first such problem.
When loading the DBI stream, before anyone has even tried to
access a single record, we build an in memory map of every
source file for every module. In the particular PDB I was
using, this was over 85 million files. Specifically, the
complexity is O(m*n) where m is the number of modules and
n is the average number of source files (including headers)
per module.
The whole reason for doing this was so that we could have
constant time access to any module and any of its source
file lists. However, we can still get O(1) access to the
source file list for a given module with a simple O(m)
precomputation, and access to the list of modules is
already O(1) anyway.
So this patches reduces the O(m*n) up-front precomputation
to an O(m) one, where n is ~6,500 and n*m is about 85 million
in my pathological test case.
Zachary Turner [Thu, 4 May 2017 23:53:01 +0000 (23:53 +0000)]
[llvm-pdbdump] Only build the TypeDatabase if necessary.
Building the type database is expensive, and can take multiple
minutes for large PDBs. But we only need it in certain cases
depending on what command line options are specified. So only
build it when we know we're about to need it.
Craig Topper [Thu, 4 May 2017 21:45:49 +0000 (21:45 +0000)]
[JumpThreading] When processing compares, explicitly check that the result type is not a vector rather than check for it being an integer.
Compares always return a scalar integer or vector of integers. isIntegerTy returns false for vectors, but that's not completely obvious. So using isVectorTy is less confusing.
Sanjay Patel [Thu, 4 May 2017 19:51:34 +0000 (19:51 +0000)]
[InstSimplify] add folds for or-of-casted-icmps
The sibling folds for 'and' with casts were added with https://reviews.llvm.org/rL273200.
This is a preliminary step for adding the 'or' variants for the folds added with https://reviews.llvm.org/rL301260.
The reason for the strange form with constant LHS in the 1st test is because there's another missing fold in that
case for the inverted predicate. That should be fixed when we add the ConstantRange functionality for 'or-of-icmps'
that already exists for 'and-of-icmps'.
I'm hoping to share more code for the and/or cases, so we won't have these differences. This will allow us to remove
code from InstCombine. It's also possible that we can remove some code here in InstSimplify. I think we have some
duplicated folds because patterns are not matched in a general way.
Reid Kleckner [Thu, 4 May 2017 18:19:52 +0000 (18:19 +0000)]
[ms-inline-asm] Use the frontend size only for ambiguous instructions
This avoids problems on code like this:
char buf[16];
__asm {
movups xmm0, [buf]
mov [buf], eax
}
The frontend size in this case (1) is wrong, and the register makes the
instruction matching unambiguous. There are also enough bytes available
that we shouldn't complain to the user that they are potentially using
an incorrectly sized instruction to access the variable.
Craig Topper [Thu, 4 May 2017 17:00:41 +0000 (17:00 +0000)]
[APInt] Reduce number of allocations involved in multiplying. Reduce worst case multiply size
Currently multiply is implemented in operator*=. Operator* makes a copy and uses operator*= to modify the copy.
Operator*= itself allocates a temporary buffer to hold the multiply result as it computes it. Then copies it to the buffer in *this.
Operator*= attempts to bound the size of the result based on the number of active bits in its inputs. It also has a couple special cases to handle 0 inputs without any memory allocations or multiply operations. The best case is that it calculates a single word regardless of input bit width. The worst case is that it calculates the a 2x input width result and drop the upper bits.
Since operator* uses operator*= it incurs two allocations, one for a copy of *this and one for the temporary allocation. Neither of these allocations are kept after the method operation is done.
The main usage in the backend appears to be ConstantRange::multiply which uses operator* rather than operator*=.
This patch moves the multiply operation to operator* and implements operator*= using it. This avoids the copy in operator*. operator* now allocates a result buffer sized the same width as its inputs no matter what. This buffer will be used as the buffer for the returned APInt. Finally, we reuse tcMultiply to implement the multiply operation. This function is capable of not calculating additional upper words that will be discarded.
This change does lose the special optimizations for the inputs using less words than their size implies. But it also removed the getActiveBits calls from all multiplies. If we think those optimizations are important we could look at providing additional bounds to tcMultiply to limit the computations.
Jonas Paulsson [Thu, 4 May 2017 13:33:30 +0000 (13:33 +0000)]
[SystemZ] Make copyPhysReg() add impl-use operands of super reg.
When a 128 bit COPY is lowered into two instructions, an impl-use operand of
the super-reg should be added to each new instruction in case one of the
sub-regs is undefined.
projects / llvm / log