[Bug target/109974] New: RISCV: RVV VSETVL Pass ICE in SLP auto-vectorization

[pan2.li at intel dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=109974

            Bug ID: 109974
           Summary: RISCV: RVV VSETVL Pass ICE in SLP auto-vectorization
           Product: gcc
           Version: 14.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: target
          Assignee: unassigned at gcc dot gnu.org
          Reporter: pan2.li at intel dot com
  Target Milestone: ---

Created attachment 55160
  --> https://gcc.gnu.org/bugzilla/attachment.cgi?id=55160&action=edit
Reproduce source file

Given the below example code with build option " -march=rv64gcv_zbb -O3
--param=riscv-autovec-preference=fixed-vlmax".

#include <stdint-gcc.h>

void __attribute__((noinline, noclone))
func (int8_t *__restrict x, int64_t *__restrict y, int n)
{
  for (int i = 0, j = 0; i < n; i++, j +=2 )
  {
    x[i + 0] += 1;
    y[j + 0] += 1;
    y[j + 1] += 2;
  }
}

It will trigger one ICE during RTL pass: vsetvl.

        .file   "test.c"
        .option nopic
        .attribute arch,
"rv64i2p1_m2p0_a2p1_f2p2_d2p2_c2p0_v1p0_zicsr2p0_zifencei2p0_zbb1p0_zve32f1p0_zve32x1p0_zve64d1p0_zve64f1p0_zve64x1p0_zvl128b1p0_zvl32b1p0_zvl64b1p0"
        .attribute unaligned_access, 0
        .attribute stack_align, 16
        .text
during RTL pass: vsetvl
test.c: In function ‘func’:
test.c:12:1: internal compiler error: in source_equal_p, at
config/riscv/riscv-vsetvl.cc:1141
   12 | }
      | ^
0x1cd6902 source_equal_p
       
/home/pli/repos/gcc/reference/riscv-gnu-toolchain/gcc/__BUILD_RISC-V/../gcc/config/riscv/riscv-vsetvl.cc:1141
0x1cd7c59 riscv_vector::avl_info::single_source_equal_p(riscv_vector::avl_info
const&) const
       
/home/pli/repos/gcc/reference/riscv-gnu-toolchain/gcc/__BUILD_RISC-V/../gcc/config/riscv/riscv-vsetvl.cc:1658
0x1cd7f01 riscv_vector::avl_info::operator==(riscv_vector::avl_info const&)
const
       
/home/pli/repos/gcc/reference/riscv-gnu-toolchain/gcc/__BUILD_RISC-V/../gcc/config/riscv/riscv-vsetvl.cc:1722
0x1cd8fe0
riscv_vector::vector_insn_info::compatible_avl_p(riscv_vector::vl_vtype_info
const&) const
       
/home/pli/repos/gcc/reference/riscv-gnu-toolchain/gcc/__BUILD_RISC-V/../gcc/config/riscv/riscv-vsetvl.cc:2010
0x1cd6ce4 incompatible_avl_p
       
/home/pli/repos/gcc/reference/riscv-gnu-toolchain/gcc/__BUILD_RISC-V/../gcc/config/riscv/riscv-vsetvl.cc:1199
0x1ce453b
riscv_vector::demands_cond::dual_incompatible_p(riscv_vector::vector_insn_info
const&, riscv_vector::vector_insn_info const&) const
       
/home/pli/repos/gcc/reference/riscv-gnu-toolchain/gcc/__BUILD_RISC-V/../gcc/config/riscv/riscv-vsetvl.h:491
0x1cd8e36
riscv_vector::vector_insn_info::compatible_p(riscv_vector::vector_insn_info
const&) const
       
/home/pli/repos/gcc/reference/riscv-gnu-toolchain/gcc/__BUILD_RISC-V/../gcc/config/riscv/riscv-vsetvl.cc:1983
0x1cdbf13 pass_vsetvl::compute_local_backward_infos(rtl_ssa::bb_info const*)
       
/home/pli/repos/gcc/reference/riscv-gnu-toolchain/gcc/__BUILD_RISC-V/../gcc/config/riscv/riscv-vsetvl.cc:2819
0x1ce188b pass_vsetvl::lazy_vsetvl()
       
/home/pli/repos/gcc/reference/riscv-gnu-toolchain/gcc/__BUILD_RISC-V/../gcc/config/riscv/riscv-vsetvl.cc:4542
0x1ce1b40 pass_vsetvl::execute(function*)
       
/home/pli/repos/gcc/reference/riscv-gnu-toolchain/gcc/__BUILD_RISC-V/../gcc/config/riscv/riscv-vsetvl.cc:4601
Please submit a full bug report, with preprocessed source (by using
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Please include the complete backtrace with any bug report.
See <https://gcc.gnu.org/bugs/> for instructions.