RISC-V: Add testcases for unsigned vector SAT_SUB form 11 and form 12

RISC-V: Add testcases for unsigned vector SAT_SUB form 11 and form 12

This patch adds testcase for form11 and form12, as shown below:

void __attribute__((noinline))                                       \
vec_sat_u_sub_##T##_fmt_11 (T *out, T *op_1, T *op_2, unsigned limit) \
{                                                                    \
  unsigned i;                                                        \
  for (i = 0; i < limit; i++)                                        \
    {                                                                \
      T x = op_1[i];                                                 \
      T y = op_2[i];                                                 \
      T ret;                                                         \
      T overflow = __builtin_sub_overflow (x, y, &ret);           \
      out[i] = overflow ? 0 : ret;                                   \
    }                                                                \
}

void __attribute__((noinline))                                        \
vec_sat_u_sub_##T##_fmt_12 (T *out, T *op_1, T *op_2, unsigned limit) \
{                                                                     \
  unsigned i;                                                         \
  for (i = 0; i < limit; i++)                                         \
    {                                                                 \
      T x = op_1[i];                                                  \
      T y = op_2[i];                                                  \
      T ret;                                                          \
      T overflow = __builtin_sub_overflow (x, y, &ret);            \
      out[i] = !overflow ? ret : 0;                                   \
    }                                                                 \
}

Passed the rv64gcv regression test.

Signed-off-by: Ciyan Pan <panciyan@eswincomputing.com>
gcc/testsuite/ChangeLog:

	* gcc.target/riscv/rvv/autovec/sat/vec_sat_arith.h: Unsigned vector SAT_SUB form11 form12.
	* gcc.target/riscv/rvv/autovec/sat/vec_sat_data.h: Use ussub instead of usub.
	* gcc.target/riscv/rvv/autovec/sat/vec_sat_u_sub-run-1-u16.c: Use ussub instead of usub.
	* gcc.target/riscv/rvv/autovec/sat/vec_sat_u_sub-run-1-u32.c: Use ussub instead of usub.
	* gcc.target/riscv/rvv/autovec/sat/vec_sat_u_sub-run-1-u64.c: Use ussub instead of usub.
	* gcc.target/riscv/rvv/autovec/sat/vec_sat_u_sub-run-1-u8.c: Use ussub instead of usub.
	* gcc.target/riscv/rvv/autovec/sat/vec_sat_u_sub-run-10-u16.c: Use ussub instead of usub.
	* gcc.target/riscv/rvv/autovec/sat/vec_sat_u_sub-run-10-u32.c: Use ussub instead of usub.
	* gcc.target/riscv/rvv/autovec/sat/vec_sat_u_sub-run-10-u64.c: Use ussub instead of usub.
	* gcc.target/riscv/rvv/autovec/sat/vec_sat_u_sub-run-10-u8.c: Use ussub instead of usub.
	* gcc.target/riscv/rvv/autovec/sat/vec_sat_u_sub-run-2-u16.c: Use ussub instead of usub.
	* gcc.target/riscv/rvv/autovec/sat/vec_sat_u_sub-run-2-u32.c: Use ussub instead of usub.
	* gcc.target/riscv/rvv/autovec/sat/vec_sat_u_sub-run-2-u64.c: Use ussub instead of usub.
	* gcc.target/riscv/rvv/autovec/sat/vec_sat_u_sub-run-2-u8.c: Use ussub instead of usub.
	* gcc.target/riscv/rvv/autovec/sat/vec_sat_u_sub-run-3-u16.c: Use ussub instead of usub.
	* gcc.target/riscv/rvv/autovec/sat/vec_sat_u_sub-run-3-u32.c: Use ussub instead of usub.
	* gcc.target/riscv/rvv/autovec/sat/vec_sat_u_sub-run-3-u64.c: Use ussub instead of usub.
	* gcc.target/riscv/rvv/autovec/sat/vec_sat_u_sub-run-3-u8.c: Use ussub instead of usub.
	* gcc.target/riscv/rvv/autovec/sat/vec_sat_u_sub-run-4-u16.c: Use ussub instead of usub.
	* gcc.target/riscv/rvv/autovec/sat/vec_sat_u_sub-run-4-u32.c: Use ussub instead of usub.
	* gcc.target/riscv/rvv/autovec/sat/vec_sat_u_sub-run-4-u64.c: Use ussub instead of usub.
	* gcc.target/riscv/rvv/autovec/sat/vec_sat_u_sub-run-4-u8.c: Use ussub instead of usub.
	* gcc.target/riscv/rvv/autovec/sat/vec_sat_u_sub-run-5-u16.c: Use ussub instead of usub.
	* gcc.target/riscv/rvv/autovec/sat/vec_sat_u_sub-run-5-u32.c: Use ussub instead of usub.
	* gcc.target/riscv/rvv/autovec/sat/vec_sat_u_sub-run-5-u64.c: Use ussub instead of usub.
	* gcc.target/riscv/rvv/autovec/sat/vec_sat_u_sub-run-5-u8.c: Use ussub instead of usub.
	* gcc.target/riscv/rvv/autovec/sat/vec_sat_u_sub-run-6-u16.c: Use ussub instead of usub.
	* gcc.target/riscv/rvv/autovec/sat/vec_sat_u_sub-run-6-u32.c: Use ussub instead of usub.
	* gcc.target/riscv/rvv/autovec/sat/vec_sat_u_sub-run-6-u64.c: Use ussub instead of usub.
	* gcc.target/riscv/rvv/autovec/sat/vec_sat_u_sub-run-6-u8.c: Use ussub instead of usub.
	* gcc.target/riscv/rvv/autovec/sat/vec_sat_u_sub-run-7-u16.c: Use ussub instead of usub.
	* gcc.target/riscv/rvv/autovec/sat/vec_sat_u_sub-run-7-u32.c: Use ussub instead of usub.
	* gcc.target/riscv/rvv/autovec/sat/vec_sat_u_sub-run-7-u64.c: Use ussub instead of usub.
	* gcc.target/riscv/rvv/autovec/sat/vec_sat_u_sub-run-7-u8.c: Use ussub instead of usub.
	* gcc.target/riscv/rvv/autovec/sat/vec_sat_u_sub-run-8-u16.c: Use ussub instead of usub.
	* gcc.target/riscv/rvv/autovec/sat/vec_sat_u_sub-run-8-u32.c: Use ussub instead of usub.
	* gcc.target/riscv/rvv/autovec/sat/vec_sat_u_sub-run-8-u64.c: Use ussub instead of usub.
	* gcc.target/riscv/rvv/autovec/sat/vec_sat_u_sub-run-8-u8.c: Use ussub instead of usub.
	* gcc.target/riscv/rvv/autovec/sat/vec_sat_u_sub-run-9-u16.c: Use ussub instead of usub.
	* gcc.target/riscv/rvv/autovec/sat/vec_sat_u_sub-run-9-u32.c: Use ussub instead of usub.
	* gcc.target/riscv/rvv/autovec/sat/vec_sat_u_sub-run-9-u64.c: Use ussub instead of usub.
	* gcc.target/riscv/rvv/autovec/sat/vec_sat_u_sub-run-9-u8.c: Use ussub instead of usub.
	* gcc.target/riscv/rvv/autovec/sat/vec_sat_u_sub-11-u16.c: New test.
	* gcc.target/riscv/rvv/autovec/sat/vec_sat_u_sub-11-u32.c: New test.
	* gcc.target/riscv/rvv/autovec/sat/vec_sat_u_sub-11-u64.c: New test.
	* gcc.target/riscv/rvv/autovec/sat/vec_sat_u_sub-11-u8.c: New test.
	* gcc.target/riscv/rvv/autovec/sat/vec_sat_u_sub-12-u16.c: New test.
	* gcc.target/riscv/rvv/autovec/sat/vec_sat_u_sub-12-u32.c: New test.
	* gcc.target/riscv/rvv/autovec/sat/vec_sat_u_sub-12-u64.c: New test.
	* gcc.target/riscv/rvv/autovec/sat/vec_sat_u_sub-12-u8.c: New test.
	* gcc.target/riscv/rvv/autovec/sat/vec_sat_u_sub-run-11-u16.c: New test.
	* gcc.target/riscv/rvv/autovec/sat/vec_sat_u_sub-run-11-u32.c: New test.
	* gcc.target/riscv/rvv/autovec/sat/vec_sat_u_sub-run-11-u64.c: New test.
	* gcc.target/riscv/rvv/autovec/sat/vec_sat_u_sub-run-11-u8.c: New test.
	* gcc.target/riscv/rvv/autovec/sat/vec_sat_u_sub-run-12-u16.c: New test.
	* gcc.target/riscv/rvv/autovec/sat/vec_sat_u_sub-run-12-u32.c: New test.
	* gcc.target/riscv/rvv/autovec/sat/vec_sat_u_sub-run-12-u64.c: New test.
	* gcc.target/riscv/rvv/autovec/sat/vec_sat_u_sub-run-12-u8.c: New test.