https://gcc.gnu.org/bugzilla/show_bug.cgi?id=112891
--- Comment #3 from Hongtao Liu <liuhongt at gcc dot gnu.org> --- (In reply to Hongtao Liu from comment #2) > (In reply to Hongtao Liu from comment #1) > > Aaused by r10-3477-g2a2e3a0dfcbe08, Can be fixed by revert the patch. > > > > --- a/gcc/config/i386/i386.cc > > +++ b/gcc/config/i386/i386.cc > > @@ -15032,14 +15032,7 @@ ix86_avx_u128_mode_needed (rtx_insn *insn) > > if (avx_upper_reg_found) > > return AVX_U128_DIRTY; > > > > - /* If the function is known to preserve some SSE registers, > > - RA and previous passes can legitimately rely on that for > > - modes wider than 256 bits. It's only safe to issue a > > - vzeroupper if all SSE registers are clobbered. */ > > - const function_abi &abi = insn_callee_abi (insn); > > - if (vzeroupper_pattern (PATTERN (insn), VOIDmode) > > - || !hard_reg_set_subset_p (reg_class_contents[SSE_REGS], > > - abi.mode_clobbers (V4DImode))) > > + if (vzeroupper_pattern (PATTERN (insn), VOIDmode)) > > return AVX_U128_ANY; > > > > return AVX_U128_CLEAN; > Remove this regressed many testcases > > So it looks like we need to handle ix86_avx_u128_mode_after > > --- a/gcc/config/i386/i386.cc > +++ b/gcc/config/i386/i386.cc > @@ -15177,7 +15177,14 @@ ix86_avx_u128_mode_after (int mode, rtx_insn *insn) > bool avx_upper_reg_found = false; > note_stores (insn, ix86_check_avx_upper_stores, &avx_upper_reg_found); > > - return avx_upper_reg_found ? AVX_U128_DIRTY : AVX_U128_CLEAN; > + if (avx_upper_reg_found) > + return AVX_U128_DIRTY; > + > + const function_abi &abi = insn_callee_abi (insn); > + if (!hard_reg_set_subset_p (reg_class_contents[SSE_REGS], > + abi.mode_clobbers (V4DImode))) > + return AVX_U128_ANY; > + return AVX_U128_CLEAN; > } Also for sibcall, we should return AVX_U128_CLEAN for ix86_avx_u128_mode_needed.
