llvm /
llvm /
25aad6c4139ed0a45ef7c0a0de047c89c8e3ab2a [X86] Don't avoid folding multiple use sign extended 8-bit immediate into instructions under optsize.
Under optsize we try to avoid folding immediates into instructions under optsize. But if the immediate is 16-bits or 32 bits, but can be encoded as an 8-bit immediate we don't save enough from disabling the folding unless the immediate has enough uses to make up for the size of the move which is either 3 bytes or 5 bytes since there are no sign extended 8-bit moves. We would also save something if the immediate was a live out of the basic block and thus a move was unavoidable, but that would require a more advanced heuristic than just counting uses.
Note we only avoid folding multiple use immediates into the patterns that use X86ISD::ADD/SUB/XOR/OR/AND/CMP/ADC/SBB nodes and not the more common ISD::ADD/SUB/XOR/OR/AND nodes.
Differential Revision: https://reviews.llvm.org/D59522
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@356688 91177308-0d34-0410-b5e6-96231b3b80d8
5 files changed