From: Juzhe-Zhong <juzhe.zh...@rivai.ai> This patch fix bug: https://gcc.gnu.org/bugzilla/show_bug.cgi?id=109399
PR 109399 gcc/ChangeLog: * config/riscv/riscv-vsetvl.cc (pass_vsetvl::compute_local_backward_infos): Update user vsetvl in local demand fusion. gcc/testsuite/ChangeLog: * gcc.target/riscv/rvv/vsetvl/pr109399.c: New test. --- gcc/config/riscv/riscv-vsetvl.cc | 8 +++++++- .../gcc.target/riscv/rvv/vsetvl/pr109399.c | 14 ++++++++++++++ 2 files changed, 21 insertions(+), 1 deletion(-) create mode 100644 gcc/testsuite/gcc.target/riscv/rvv/vsetvl/pr109399.c diff --git a/gcc/config/riscv/riscv-vsetvl.cc b/gcc/config/riscv/riscv-vsetvl.cc index 4d043c0645b..7e8a5376705 100644 --- a/gcc/config/riscv/riscv-vsetvl.cc +++ b/gcc/config/riscv/riscv-vsetvl.cc @@ -2715,7 +2715,13 @@ pass_vsetvl::compute_local_backward_infos (const bb_info *bb) if (!(propagate_avl_across_demands_p (change, info) && !reg_available_p (insn, change)) && change.compatible_p (info)) - info = change.merge (info); + { + info = change.merge (info); + /* Fix PR109399, we should update user vsetvl instruction + if there is a change in demand fusion. */ + if (vsetvl_insn_p (insn->rtl ())) + change_vsetvl_insn (insn, info); + } } change = info; } diff --git a/gcc/testsuite/gcc.target/riscv/rvv/vsetvl/pr109399.c b/gcc/testsuite/gcc.target/riscv/rvv/vsetvl/pr109399.c new file mode 100644 index 00000000000..b3abad7a8bf --- /dev/null +++ b/gcc/testsuite/gcc.target/riscv/rvv/vsetvl/pr109399.c @@ -0,0 +1,14 @@ +/* { dg-do compile } */ +/* { dg-options "-march=rv32gcv -mabi=ilp32 -fno-tree-vectorize -fno-schedule-insns -fno-schedule-insns2" } */ + +#include "riscv_vector.h" + +void foo(void *in1, void *in2, void *in3, void *out, size_t n) { + size_t vl = __riscv_vsetvlmax_e32m1(); + vint32m1_t a = __riscv_vle32_v_i32m1(in1, vl); + vint32m1_t b = __riscv_vle32_v_i32m1_tu(a, in2, vl); + vint32m1_t c = __riscv_vle32_v_i32m1_tu(b, in3, vl); + __riscv_vse32_v_i32m1(out, c, vl); +} + +/* { dg-final { scan-assembler-times {vsetvli\s+[a-x0-9]+,\s*zero,\s*e32,\s*m1,\s*tu,\s*m[au]} 1 { target { no-opts "-O0" no-opts "-Os" no-opts "-Oz" no-opts "-funroll-loops" no-opts "-g" } } } } */ -- 2.36.3