efriedma added inline comments.
================ Comment at: llvm/lib/Target/PowerPC/PPCInstr64Bit.td:831 +// 64bit version of popcntb for 64bit sized unsigned long. +let isCodeGenOnly = 1 in +def POPCNTB8 : XForm_11<31, 122, (outs g8rc:$rA), (ins g8rc:$rS), ---------------- I'm sort of confused by the instruction variations here... let me see if I'm understanding correctly: 1. popcntb always produces a 64-bit result. 2. The 32-bit variation of the intrinsic just throws away the high bits. 3. We can't use the 64-bit instruction in "32-bit" mode because we marked the register class illegal in isel, and Feature64BitRegs has been marked "beta" for the last 15 years. 4. Therefore, there are two versions of the instruction: the real instruction that produces a 64-bit result, and a fake version of the instruction we can use in 32-bit mode. Repository: rG LLVM Github Monorepo CHANGES SINCE LAST ACTION https://reviews.llvm.org/D105360/new/ https://reviews.llvm.org/D105360 _______________________________________________ cfe-commits mailing list cfe-commits@lists.llvm.org https://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits
