RISC-V: Implement IFN SAT_ADD for both the scalar and vector

The patch implement the SAT_ADD in the riscv backend as the
sample for both the scalar and vector.  Given below vector
as example:

void vec_sat_add_u64 (uint64_t *out, uint64_t *x, uint64_t *y, unsigned n)
{
  unsigned i;

  for (i = 0; i < n; i++)
    out[i] = (x[i] + y[i]) | (- (uint64_t)((uint64_t)(x[i] + y[i]) < x[i]));
}

Before this patch:
vec_sat_add_u64:
  ...
  vsetvli a5,a3,e64,m1,ta,ma
  vle64.v v0,0(a1)
  vle64.v v1,0(a2)
  slli    a4,a5,3
  sub     a3,a3,a5
  add     a1,a1,a4
  add     a2,a2,a4
  vadd.vv v1,v0,v1
  vmsgtu.vv       v0,v0,v1
  vmerge.vim      v1,v1,-1,v0
  vse64.v v1,0(a0)
  ...

After this patch:
vec_sat_add_u64:
  ...
  vsetvli a5,a3,e64,m1,ta,ma
  vle64.v v1,0(a1)
  vle64.v v2,0(a2)
  slli    a4,a5,3
  sub     a3,a3,a5
  add     a1,a1,a4
  add     a2,a2,a4
  vsaddu.vv       v1,v1,v2  <=  Vector Single-Width Saturating Add
  vse64.v v1,0(a0)
  ...

The below test suites are passed for this patch.
* The riscv fully regression tests.
* The aarch64 fully regression tests.
* The x86 bootstrap tests.
* The x86 fully regression tests.

	PR target/51492
	PR target/112600

gcc/ChangeLog:

	* config/riscv/autovec.md (usadd<mode>3): New pattern expand for
	the unsigned SAT_ADD in vector mode.
	* config/riscv/riscv-protos.h (riscv_expand_usadd): New func decl
	to expand usadd<mode>3 pattern.
	(expand_vec_usadd): Ditto but for vector.
	* config/riscv/riscv-v.cc (emit_vec_saddu): New func impl to emit
	the vsadd insn.
	(expand_vec_usadd): New func impl to expand usadd<mode>3 for vector.
	* config/riscv/riscv.cc (riscv_expand_usadd): New func impl to
	expand usadd<mode>3 for scalar.
	* config/riscv/riscv.md (usadd<mode>3): New pattern expand for
	the unsigned SAT_ADD in scalar mode.
	* config/riscv/vector.md: Allow VLS mode for vsaddu.

gcc/testsuite/ChangeLog:

	* gcc.target/riscv/rvv/autovec/binop/vec_sat_binary.h: New test.
	* gcc.target/riscv/rvv/autovec/binop/vec_sat_u_add-1.c: New test.
	* gcc.target/riscv/rvv/autovec/binop/vec_sat_u_add-2.c: New test.
	* gcc.target/riscv/rvv/autovec/binop/vec_sat_u_add-3.c: New test.
	* gcc.target/riscv/rvv/autovec/binop/vec_sat_u_add-4.c: New test.
	* gcc.target/riscv/rvv/autovec/binop/vec_sat_u_add-run-1.c: New test.
	* gcc.target/riscv/rvv/autovec/binop/vec_sat_u_add-run-2.c: New test.
	* gcc.target/riscv/rvv/autovec/binop/vec_sat_u_add-run-3.c: New test.
	* gcc.target/riscv/rvv/autovec/binop/vec_sat_u_add-run-4.c: New test.
	* gcc.target/riscv/sat_arith.h: New test.
	* gcc.target/riscv/sat_u_add-1.c: New test.
	* gcc.target/riscv/sat_u_add-2.c: New test.
	* gcc.target/riscv/sat_u_add-3.c: New test.
	* gcc.target/riscv/sat_u_add-4.c: New test.
	* gcc.target/riscv/sat_u_add-run-1.c: New test.
	* gcc.target/riscv/sat_u_add-run-2.c: New test.
	* gcc.target/riscv/sat_u_add-run-3.c: New test.
	* gcc.target/riscv/sat_u_add-run-4.c: New test.
	* gcc.target/riscv/scalar_sat_binary.h: New test.

Signed-off-by: Pan Li <pan2.li@intel.com>

0 files changed, 0 insertions, 0 deletions