https://gcc.gnu.org/g:b2d0abfcd5a3a58e7967eb76bb3508e5ef20d9fa
commit r16-5801-gb2d0abfcd5a3a58e7967eb76bb3508e5ef20d9fa Author: Robin Dapp <[email protected]> Date: Wed Nov 12 10:17:47 2025 +0100 RISC-V: vsetvl: Add null check for fault-first loop [PR122652]. For a fault-first load we store the first instruction that read its VL result. The loop to do so uses next_nondebug_insn () which returns nullptr when we are at the end. Check for that before accessing the next insn. PR target/122652 gcc/ChangeLog: * config/riscv/riscv-vsetvl.cc: Add nullptr check. gcc/testsuite/ChangeLog: * gcc.target/riscv/rvv/base/pr122652.c: New test. Diff: --- gcc/config/riscv/riscv-vsetvl.cc | 2 +- gcc/testsuite/gcc.target/riscv/rvv/base/pr122652.c | 22 ++++++++++++++++++++++ 2 files changed, 23 insertions(+), 1 deletion(-) diff --git a/gcc/config/riscv/riscv-vsetvl.cc b/gcc/config/riscv/riscv-vsetvl.cc index 580ac9cbe8e8..127187b45552 100644 --- a/gcc/config/riscv/riscv-vsetvl.cc +++ b/gcc/config/riscv/riscv-vsetvl.cc @@ -1176,7 +1176,7 @@ public: if (fault_first_load_p (insn->rtl ())) { for (insn_info *i = insn->next_nondebug_insn (); - i->bb () == insn->bb (); i = i->next_nondebug_insn ()) + i && i->bb () == insn->bb (); i = i->next_nondebug_insn ()) { if (find_access (i->defs (), VL_REGNUM)) break; diff --git a/gcc/testsuite/gcc.target/riscv/rvv/base/pr122652.c b/gcc/testsuite/gcc.target/riscv/rvv/base/pr122652.c new file mode 100644 index 000000000000..bd8f1b4d3ef2 --- /dev/null +++ b/gcc/testsuite/gcc.target/riscv/rvv/base/pr122652.c @@ -0,0 +1,22 @@ +/* { dg-do compile } */ +/* { dg-options "-O3 -march=rv64gcv -mabi=lp64d" } */ + +#include "riscv_vector.h" + +int a; +int b(); + +int c() { + if (b()) + a = 0; +} + +void d() { + for (; c() + d;) { + long e, h; + char *f; + __rvv_uint16mf4_t g; + __rvv_uint8mf8x3_t i = __riscv_vlseg3e8ff_v_u8mf8x3(f, &h, e); + __riscv_vsoxseg3ei16_v_u8mf8x3(0, g, i, 0); + } +}
