https://gcc.gnu.org/bugzilla/show_bug.cgi?id=99930
Richard Biener <rguenth at gcc dot gnu.org> changed: What |Removed |Added ---------------------------------------------------------------------------- CC| |segher at gcc dot gnu.org --- Comment #2 from Richard Biener <rguenth at gcc dot gnu.org> --- Seems because of r93 being live: insn_cost 8 for 9: r93:V4SF=[`*.LC0'] REG_EQUAL const_vector insn_cost 4 for 10: {r91:SF=abs(r92:SF);use r93:V4SF;clobber flags:CC;} REG_DEAD r92:SF REG_UNUSED flags:CC insn_cost 8 for 11: r95:V4SF=[`*.LC1'] REG_EQUAL const_vector insn_cost 4 for 12: {r94:SF=-r91:SF;use r95:V4SF;clobber flags:CC;} REG_DEAD r91:SF REG_UNUSED flags:CC insn_cost 4 for 13: flags:CCFP=cmp(r90:SF,r94:SF) REG_DEAD r94:SF insn_cost 12 for 14: pc={(flags:CCFP>0)?L35:pc} REG_DEAD flags:CCFP REG_BR_PROB 59055804 insn_cost 8 for 16: r97:SF=[r89:DI+0x4] REG_DEAD r89:DI insn_cost 4 for 18: {r96:SF=abs(r97:SF);use r93:V4SF;clobber flags:CC;} REG_DEAD r97:SF REG_DEAD r93:V4SF REG_UNUSED flags:CC insn_cost 4 for 20: {r99:SF=-r96:SF;use r95:V4SF;clobber flags:CC;} REG_DEAD r96:SF REG_DEAD r95:V4SF REG_UNUSED flags:CC while at -O1 we have two loads of LC0 and r93 is dead after insn 10.