On Sat, Apr 16, 2016 at 8:17 PM, Nicolai Hähnle <nhaeh...@gmail.com> wrote: > On 16.04.2016 05:20, Marek Olšák wrote: >> >> On Sat, Apr 16, 2016 at 8:04 AM, Michel Dänzer <mic...@daenzer.net> wrote: >>> >>> On 16.04.2016 14:51, Michel Dänzer wrote: >>>> >>>> On 16.04.2016 11:39, Tom Stellard wrote: >>>>> >>>>> The ds_bpermute instruction allows threads to transfer data directly >>>>> to or from the vgprs of other threads. These instructions use the lds >>>>> hardware to transfer data, but do not read or write lds memory. >>>>> >>>>> DDX BEFORE: | DDX AFTER: >>>>> | >>>>> v_mbcnt_lo_u32_b32_e64 v2, -1, 0 | v_mbcnt_lo_u32_b32_e64 v2, -1, 0 >>>>> v_mbcnt_hi_u32_b32_e64 v2, -1, v2 | v_mbcnt_hi_u32_b32_e64 v2, -1, v2 >>>>> v_lshlrev_b32_e32 v4, 2, v2 | v_and_b32_e32 v2, 0x3ffffffc, v2 >>>>> v_and_b32_e32 v2, -4, v2 | v_lshlrev_b32_e32 v2, 2, v2 >>>>> v_lshlrev_b32_e32 v3, 2, v2 | ds_bpermute_b32 v3, v2, v0 >>>>> s_mov_b32 m0, -1 | ds_bpermute_b32 v0, v2, v0 >>>>> offset:4 >>>>> ds_write_b32 v4, v0 | s_waitcnt lgkmcnt(0) >>>>> s_waitcnt lgkmcnt(0) | >>>>> v_or_b32_e32 v0, 1, v2 | >>>>> v_lshlrev_b32_e32 v0, 2, v0 | >>>>> ds_read_b32 v1, v3 | >>>>> ds_read_b32 v0, v0 | >>>>> s_waitcnt lgkmcnt(0) | >>>>> | >>>>> LDS: 1 blocks | LDS: 0 blocks >>>> >>>> >>>> Nice. >>>> >>>> >>>> Were these intrinsics already available in LLVM 3.6? If not, the old >>>> code needs to be kept for backwards compatibility. >>> >>> >>> I can see now that you're taking care of this for the bpermute >>> intrinsic, but AFAICT the mbcnt intrinsics were only added in LLVM 3.8. >> >> >> How do you feel about increasing the requirement to LLVM 3.8 for Mesa git? > > > Please no. > > In addition to Gentoo and Arch mentioned by Ilia, Ubuntu also still ships > 3.7. This will change soon enough, but even then, we should give people a > few months to update. > > Let's not scare people away too much.
OK. Sounds good. Marek _______________________________________________ mesa-dev mailing list mesa-dev@lists.freedesktop.org https://lists.freedesktop.org/mailman/listinfo/mesa-dev
