Summary:
This catches malformed mir files which specify alignment as log2 instead of pow2.
See https://reviews.llvm.org/D65945 for reference,
This is patch is part of a series to introduce an Alignment type.
See this thread for context: http://lists.llvm.org/pipermail/llvm-dev/2019-July/133851.html
See this patch for the introduction of the type: https://reviews.llvm.org/D64790
Reviewers: courbet
Subscribers: MatzeB, qcolombet, dschuff, arsenm, sdardis, nemanjai, jvesely, nhaehnle, hiraditya, kbarton, asb, rbar, johnrusso, simoncook, apazos, sabuasal, niosHD, jrtc27, MaskRay, zzheng, edward-jones, atanasyan, rogfer01, MartinMosbeck, brucehoult, the_o, PkmX, jocewei, jsji, Petar.Avramovic, asbirlea, s.egerton, pzheng, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D67433
llvm-svn: 371608
Generally speaking, we lower to an optimal rotate sequence for nodes visible in
the SDAG. However, there are instances where the two rotates are not visible at
ISEL time - most notably those in a very common sequence when lowering switch
statements to jump tables.
A common situation is a switch on a 32-bit integer. This value has to have the
upper 32 bits cleared and because jump table offsets are word offsets, the value
needs to be shifted left by 2 bits. We currently emit the clear and the left
shift as two separate instructions, but this is not needed as we can lower it to
a single RLDIC.
This patch just cleans that up.
Differential revision: https://reviews.llvm.org/D60402
llvm-svn: 362576