On Mon, 28 Nov 2022, Jeff Law wrote: > > > > LGTM, but with a nit, I don't get set.w but get an andi like below, so > > > > maybe we should also scan-assembler-not andi? feel free to commit that > > > > directly with that fix > > > > > > > > ```asm > > > > sleu: > > > > sgtu a0,a0,a1 # 9 [c=4 l=4] *sgtu_disi > > > > xori a0,a0,1 # 10 [c=4 l=4] *xorsi3_internal/1 > > > > andi a0,a0,1 # 16 [c=4 l=4] anddi3/1 > > > > ret # 25 [c=0 l=4] simple_return > > > > ``` > > > Interesting. I can do that, but can you please share the compilation > > > options, given or defaulted (from `--with...' configuration options), this > > > happens with? > > I have noticed it went nowhere. Can you please check what compilation > > options lead to this discrepancy so that we can have the fix included in > > GCC 13? I'd like to understand what's going on here. > > FWIW, I don't see the redundant sign extension with this testcase at -O2 on > the trunk. Is it possible the patch has been made redundant over the last few > months?
Maybe at -O2, but the test cases continue to fail in my configuration for other optimisation levels: FAIL: gcc.target/riscv/sge.c -O1 scan-assembler-not sext\\.w FAIL: gcc.target/riscv/sge.c -Og -g scan-assembler-not sext\\.w FAIL: gcc.target/riscv/sgeu.c -O1 scan-assembler-not sext\\.w FAIL: gcc.target/riscv/sgeu.c -Og -g scan-assembler-not sext\\.w FAIL: gcc.target/riscv/sle.c -O1 scan-assembler-not sext\\.w FAIL: gcc.target/riscv/sle.c -Og -g scan-assembler-not sext\\.w FAIL: gcc.target/riscv/sleu.c -O1 scan-assembler-not sext\\.w FAIL: gcc.target/riscv/sleu.c -Og -g scan-assembler-not sext\\.w when applied on top of: $ riscv64-linux-gnu-gcc --version riscv64-linux-gnu-gcc (GCC) 13.0.0 20221128 (experimental) Not anymore with the whole patch applied. Does it make sense to bisect the change that removed the pessimisation at -O2 to understand what is going on here? I think my change is worthwhile anyway: why to rely on the optimiser to get things sorted while we can produce the best code in the backend right away in the first place? Maciej
