https://gcc.gnu.org/bugzilla/show_bug.cgi?id=119164
--- Comment #5 from GCC Commits <cvs-commit at gcc dot gnu.org> --- The master branch has been updated by Vineet Gupta <vine...@gcc.gnu.org>: https://gcc.gnu.org/g:3c0f3b74bf6011b12fe12821ba6e1079309d9445 commit r16-1290-g3c0f3b74bf6011b12fe12821ba6e1079309d9445 Author: Vineet Gupta <vine...@rivosinc.com> Date: Sun Jun 8 14:55:01 2025 -0700 RISC-V: frm/mode-switch: Reduce FRM restores on DYN transition [PR119164] FRM mode switching state machine has DYN as default state which it also fallsback to after transitioning to other states such as DYN_CALL. Currently TARGET_MODE_EMIT generates a FRM restore on any transition to DYN leading to spurious/extraneous FRM restores. Only do this if an interim static Rounding Mode was observed in the state machine. Fixes the extraneous FRM read/write in PR119164 (and also PR119832 w/o need for TARGET_MODE_CONFLUENCE). Also reduces the number of FRM writes in SPEC2017 -Ofast -mrv64gcv build significantly. Before After ------------- ------------- frrm fsrmi fsrm frrm fsrmi frrm perlbench_r 42 0 4 17 0 1 cpugcc_r 167 0 17 11 0 0 bwaves_r 16 0 1 16 0 1 mcf_r 11 0 0 11 0 0 cactusBSSN_r 76 0 27 19 0 1 namd_r 119 0 63 14 0 1 parest_r 168 0 114 24 0 1 povray_r 123 1 17 26 1 6 lbm_r 6 0 0 6 0 0 omnetpp_r 17 0 1 17 0 1 wrf_r 2287 13 1956 1268 13 1603 cpuxalan_r 17 0 1 17 0 1 ldecod_r 11 0 0 11 0 0 x264_r 14 0 1 11 0 0 blender_r 724 12 182 61 12 42 cam4_r 324 13 169 45 13 20 deepsjeng_r 11 0 0 11 0 0 imagick_r 265 16 34 132 16 25 leela_r 12 0 0 12 0 0 nab_r 13 0 1 13 0 1 exchange2_r 16 0 1 16 0 1 fotonik3d_r 20 0 11 19 0 1 roms_r 33 0 23 21 0 1 xz_r 6 0 0 6 0 0 --------------- -------------- 4498 55 2623 1804 55 1707 --------------- -------------- 7176 3566 --------------- -------------- PR target/119164 gcc/ChangeLog: * config/riscv/riscv.cc (riscv_emit_frm_mode_set): check STATIC_FRM_P for transition to DYN. gcc/testsuite/ChangeLog: * gcc.target/riscv/rvv/base/pr119164.c: New test. Signed-off-by: Vineet Gupta <vine...@rivosinc.com>
