We currently have to insert bits via a temporary variable of the same size as the target with various shift/mask stages, resulting in further temporary variables, all of which require the allocation of memory for large APInts (MaskSizeInBits > 64).
This is another of the compile time issues identified in PR32037 (see also D30265).
This patch adds the APInt::insertBits() helper method which avoids the temporary memory allocation and masks/inserts the raw bits directly into the target.
Differential Revision: https://reviews.llvm.org/D30780
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@297458 91177308-0d34-0410-b5e6-96231b3b80d8
Summary:
SmallBitVector uses a malloc for more than 58 bits on a 64-bit target and more than 27 bits on a 32-bit target. Some of the vector types we deal with here use more than those number of elements and therefore cause a malloc.
APInt on the other hand supports up to 64 bits without a malloc. That's the maximum number of bits we need here so we can avoid a malloc for all cases by using APInt. This will incur a minor increase in stack usage due to APInt storing the bit count separately from the data bits unlike SmallBitVector, but that should be ok.
Reviewers: RKSimon
Reviewed By: RKSimon
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D30386
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@296352 91177308-0d34-0410-b5e6-96231b3b80d8
The current pattern for extract bits in range is typically:
Mask.lshr(BitOffset).trunc(SubSizeInBits);
Which can be particularly slow for large APInts (MaskSizeInBits > 64) as they require the allocation of memory for the temporary variable.
This is another of the compile time issues identified in PR32037 (see also D30265).
This patch adds the APInt::extractBits() helper method which avoids the temporary memory allocation.
Differential Revision: https://reviews.llvm.org/D30336
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@296272 91177308-0d34-0410-b5e6-96231b3b80d8
The current pattern for extract bits in range is typically:
Mask.lshr(BitOffset).trunc(SubSizeInBits);
Which can be particularly slow for large APInts (MaskSizeInBits > 64) as they require the allocation of memory for the temporary variable.
This is another of the compile time issues identified in PR32037 (see also D30265).
This patch adds the APInt::extractBits() helper method which avoids the temporary memory allocation.
Differential Revision: https://reviews.llvm.org/D30336
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@296147 91177308-0d34-0410-b5e6-96231b3b80d8
The current pattern for extract bits in range is typically:
Mask.lshr(BitOffset).trunc(SubSizeInBits);
Which can be particularly slow for large APInts (MaskSizeInBits > 64) as they require the allocation of memory for the temporary variable.
This is another of the compile time issues identified in PR32037 (see also D30265).
This patch adds the APInt::extractBits() helper method which avoids the temporary memory allocation.
Differential Revision: https://reviews.llvm.org/D30336
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@296141 91177308-0d34-0410-b5e6-96231b3b80d8
The current pattern for setting bits in range is typically:
Mask |= APInt::getBitsSet(MaskSizeInBits, LoPos, HiPos);
Which can be particularly slow for large APInts (MaskSizeInBits > 64) as they require the allocation memory for the temporary variable.
This is one of the key compile time issues identified in PR32037.
This patch adds the APInt::setBits() helper method which avoids the temporary memory allocation completely, this first implementation uses setBit() internally instead but already significantly reduces the regression in PR32037 (~10% drop). Additional optimization may be possible.
I investigated whether there is need for APInt::clearBits() and APInt::flipBits() equivalents but haven't seen these patterns to be particularly common, but reusing the code would be trivial.
Differential Revision: https://reviews.llvm.org/D30265
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@296102 91177308-0d34-0410-b5e6-96231b3b80d8
Summary: This is especially important for 32-bit targets with 64-bit shuffle elements.This is similar to how PSHUFB and VPERMIL handle the same problem.
Reviewers: RKSimon
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D25666
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@284451 91177308-0d34-0410-b5e6-96231b3b80d8
The shuffle mask decodes have a large amount of repeated code extracting/splitting mask values from Constant data.
This patch pulls all of this duplicated code into a single helper function to identify undef elements and combine/split constant integer data into the requested shuffle mask elements.
Updated PSHUFB/VPERMIL/VPERMIL2/VPPERM decoders to use it (VPERMV/VPERMV3 could be converted as well in the future).
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@282720 91177308-0d34-0410-b5e6-96231b3b80d8
Corrected element mask masking to extract the bottom index bits (now matches the perm2 implementation but for unary inputs).
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@274571 91177308-0d34-0410-b5e6-96231b3b80d8
This patch adds support for decoding XOP VPPERM instruction when it represents a basic shuffle.
The mask decoding required the existing MCInstrLowering code to be updated to support binary shuffles - the implementation now matches what is done in X86InstrComments.cpp.
Differential Revision: http://reviews.llvm.org/D18441
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@265874 91177308-0d34-0410-b5e6-96231b3b80d8
Patch to add support for target shuffle combining of X86ISD::VPERMV3 nodes, including support for detecting unary shuffles.
This uncovered several issues with the X86ISD::VPERMV3 shuffle mask decoding of non-64 bit shuffle mask elements - the bit masking wasn't being correctly computed.
Removed non-constant pool mask decode path as we have no way of testing it right now.
Differential Revision: http://reviews.llvm.org/D17916
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@262809 91177308-0d34-0410-b5e6-96231b3b80d8
In cases where the PSHUFB shuffle mask is shared it might not be bitcasted to a vXi8 byte vector. This patch adds support for decoding these wider shuffle masks from the ConstantPool.
The test case in question makes use of this to recognise the shuffle mask is an unary UNPCKL pattern and simplifies accordingly.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@261201 91177308-0d34-0410-b5e6-96231b3b80d8
