Re: [cfe-users] eBPF: Odd optimization results with clang-5.0

2018-01-15 Thread Yonghong Song via cfe-users
On 1/8/18 5:45 AM, Jiong Wang wrote: On 05/01/2018 20:05, Alexei Starovoitov wrote: On Fri, Jan 5, 2018 at 7:01 AM, Charlemagne Lasse wrote: First thing is the odd way how 8 bit loads to an uint8_t are handled (see bug1_sec): I could reproduce both issues on other targets on latest LLVm t

Re: [cfe-users] eBPF: Odd optimization results with clang-5.0

2018-01-08 Thread Alexei Starovoitov via cfe-users
On Fri, Jan 5, 2018 at 7:01 AM, Charlemagne Lasse wrote: > Hi, > > just tested the clang eBPF backend. Very cool thing :) > > But I've noticed that the codegen creates really odd things which I > cannot explain from my understanding of the ISA. My test is attached > and was compiled via: > > clan

Re: [cfe-users] eBPF: Odd optimization results with clang-5.0

2018-01-08 Thread Jiong Wang via cfe-users
On 05/01/2018 20:05, Alexei Starovoitov wrote: On Fri, Jan 5, 2018 at 7:01 AM, Charlemagne Lasse wrote: First thing is the odd way how 8 bit loads to an uint8_t are handled (see bug1_sec): I could reproduce both issues on other targets on latest LLVm trunk@321940, for example AArch64 (need t