| Message ID | 20230118025014.65261-1-juzhe.zhong@rivai.ai |
|---|---|
| State | New |
| Headers | show |
| Series | RISC-V: Change VSETVL PASS always call split_all_insns | expand |
On 1/17/23 19:50, juzhe.zhong@rivai.ai wrote: > From: Ju-Zhe Zhong <juzhe.zhong@rivai.ai> > > Since LCM will destroy CFG, we are going to reorder the location of VSETVL PASS > at least before bbro (block-reorder PASS) which is before split3 PASS. We need > to call it in VSETVL PASS to get final RVV instructions patterns. Just for the record. LCM does not destroy the CFG, it just splits critical edges. > > gcc/ChangeLog: > > * config/riscv/riscv-vsetvl.cc (pass_vsetvl::execute): Always call split_all_insns. OK. jeff
committed, thanks On Mon, Jan 23, 2023 at 3:39 AM Jeff Law via Gcc-patches < gcc-patches@gcc.gnu.org> wrote: > > > On 1/17/23 19:50, juzhe.zhong@rivai.ai wrote: > > From: Ju-Zhe Zhong <juzhe.zhong@rivai.ai> > > > > Since LCM will destroy CFG, we are going to reorder the location of > VSETVL PASS > > at least before bbro (block-reorder PASS) which is before split3 PASS. > We need > > to call it in VSETVL PASS to get final RVV instructions patterns. > Just for the record. LCM does not destroy the CFG, it just splits > critical edges. > > > > > gcc/ChangeLog: > > > > * config/riscv/riscv-vsetvl.cc (pass_vsetvl::execute): Always > call split_all_insns. > OK. > jeff >
diff --git a/gcc/config/riscv/riscv-vsetvl.cc b/gcc/config/riscv/riscv-vsetvl.cc index 0245124e28f..d494369a603 100644 --- a/gcc/config/riscv/riscv-vsetvl.cc +++ b/gcc/config/riscv/riscv-vsetvl.cc @@ -3092,12 +3092,10 @@ pass_vsetvl::execute (function *) if (n_basic_blocks_for_fn (cfun) <= 0) return 0; - /* The reason we have this since we didn't finish splitting yet - when optimize == 0. In this case, we should conservatively - split all instructions here to make sure we don't miss any - RVV instruction. */ - if (!optimize) - split_all_insns (); + /* The RVV instruction may change after split which is not a stable + instruction. We need to split it here to avoid potential issue + since the VSETVL PASS is insert before split PASS. */ + split_all_insns (); /* Early return for there is no vector instructions. */ if (!has_vector_insn (cfun))
From: Ju-Zhe Zhong <juzhe.zhong@rivai.ai> Since LCM will destroy CFG, we are going to reorder the location of VSETVL PASS at least before bbro (block-reorder PASS) which is before split3 PASS. We need to call it in VSETVL PASS to get final RVV instructions patterns. gcc/ChangeLog: * config/riscv/riscv-vsetvl.cc (pass_vsetvl::execute): Always call split_all_insns. --- gcc/config/riscv/riscv-vsetvl.cc | 10 ++++------ 1 file changed, 4 insertions(+), 6 deletions(-)