[gcc(refs/vendors/riscv/heads/gcc-15-with-riscv-opts)] RISC-V: Extract vec_duplicate for expand_const_vector [NFC]

[Jeff Law]

https://gcc.gnu.org/g:430dbc8fe6c389803d0bbf2c7a8cec2a1961f235

commit 430dbc8fe6c389803d0bbf2c7a8cec2a1961f235
Author: Pan Li <pan2.li@intel.com>
Date:   Wed Apr 16 11:16:21 2025 +0800

    RISC-V: Extract vec_duplicate for expand_const_vector [NFC]
    
    Consider the expand_const_vector is quit long (about 500 lines)
    and complicated, we would like to extract the different case
    into different functions.  For example, the const vec_duplicate
    will be extracted into expand_const_vec_duplicate.
    
    The below test suites are passed for this patch.
    * The rv64gcv fully regression test.
    
    gcc/ChangeLog:
    
            * config/riscv/riscv-v.cc (expand_const_vector): Extract
            const vec_duplicate into separated function.
            (expand_const_vec_duplicate): Add new func to take care
            of the const vec_duplicate.
    
    Signed-off-by: Pan Li <pan2.li@intel.com>
    (cherry picked from commit e6e42a709f3cd87e7a5efca72267cab57e0385cb)

Diff:
---
 gcc/config/riscv/riscv-v.cc | 92 ++++++++++++++++++++++++---------------------
 1 file changed, 50 insertions(+), 42 deletions(-)

diff --git a/gcc/config/riscv/riscv-v.cc b/gcc/config/riscv/riscv-v.cc
index d04665319ab3..edb9abcbcad7 100644
--- a/gcc/config/riscv/riscv-v.cc
+++ b/gcc/config/riscv/riscv-v.cc
@@ -1171,61 +1171,69 @@ expand_vector_init_trailing_same_elem (rtx target,
 }
 
 static void
-expand_const_vector (rtx target, rtx src)
+expand_const_vec_duplicate (rtx target, rtx src, rtx elt)
 {
   machine_mode mode = GET_MODE (target);
   rtx result = register_operand (target, mode) ? target : gen_reg_rtx (mode);
-  rtx elt;
-  if (const_vec_duplicate_p (src, &elt))
+
+  if (GET_MODE_CLASS (mode) == MODE_VECTOR_BOOL)
+    {
+      gcc_assert (rtx_equal_p (elt, const0_rtx)
+		  || rtx_equal_p (elt, const1_rtx));
+
+      rtx ops[] = {result, src};
+      emit_vlmax_insn (code_for_pred_mov (mode), UNARY_MASK_OP, ops);
+    }
+  else if (valid_vec_immediate_p (src))
     {
-      if (GET_MODE_CLASS (mode) == MODE_VECTOR_BOOL)
-	{
-	  gcc_assert (rtx_equal_p (elt, const0_rtx)
-		      || rtx_equal_p (elt, const1_rtx));
-	  rtx ops[] = {result, src};
-	  emit_vlmax_insn (code_for_pred_mov (mode), UNARY_MASK_OP, ops);
-	}
       /* Element in range -16 ~ 15 integer or 0.0 floating-point,
 	 we use vmv.v.i instruction.  */
-      else if (valid_vec_immediate_p (src))
+      rtx ops[] = {result, src};
+      emit_vlmax_insn (code_for_pred_mov (mode), UNARY_OP, ops);
+    }
+  else
+    {
+      /* Emit vec_duplicate<mode> split pattern before RA so that
+	 we could have a better optimization opportunity in LICM
+	 which will hoist vmv.v.x outside the loop and in fwprop && combine
+	 which will transform 'vv' into 'vx' instruction.
+
+	 The reason we don't emit vec_duplicate<mode> split pattern during
+	 RA since the split stage after RA is a too late stage to generate
+	 RVV instruction which need an additional register (We can't
+	 allocate a new register after RA) for VL operand of vsetvl
+	 instruction (vsetvl a5, zero).  */
+      if (lra_in_progress)
 	{
-	  rtx ops[] = {result, src};
-	  emit_vlmax_insn (code_for_pred_mov (mode), UNARY_OP, ops);
+	  rtx ops[] = {result, elt};
+	  emit_vlmax_insn (code_for_pred_broadcast (mode), UNARY_OP, ops);
 	}
       else
 	{
-	  /* Emit vec_duplicate<mode> split pattern before RA so that
-	     we could have a better optimization opportunity in LICM
-	     which will hoist vmv.v.x outside the loop and in fwprop && combine
-	     which will transform 'vv' into 'vx' instruction.
-
-	     The reason we don't emit vec_duplicate<mode> split pattern during
-	     RA since the split stage after RA is a too late stage to generate
-	     RVV instruction which need an additional register (We can't
-	     allocate a new register after RA) for VL operand of vsetvl
-	     instruction (vsetvl a5, zero).  */
-	  if (lra_in_progress)
-	    {
-	      rtx ops[] = {result, elt};
-	      emit_vlmax_insn (code_for_pred_broadcast (mode), UNARY_OP, ops);
-	    }
-	  else
-	    {
-	      struct expand_operand ops[2];
-	      enum insn_code icode = optab_handler (vec_duplicate_optab, mode);
-	      gcc_assert (icode != CODE_FOR_nothing);
-	      create_output_operand (&ops[0], result, mode);
-	      create_input_operand (&ops[1], elt, GET_MODE_INNER (mode));
-	      expand_insn (icode, 2, ops);
-	      result = ops[0].value;
-	    }
+	  struct expand_operand ops[2];
+	  enum insn_code icode = optab_handler (vec_duplicate_optab, mode);
+	  gcc_assert (icode != CODE_FOR_nothing);
+	  create_output_operand (&ops[0], result, mode);
+	  create_input_operand (&ops[1], elt, GET_MODE_INNER (mode));
+	  expand_insn (icode, 2, ops);
+	  result = ops[0].value;
 	}
-
-      if (result != target)
-	emit_move_insn (target, result);
-      return;
     }
 
+  if (result != target)
+    emit_move_insn (target, result);
+}
+
+static void
+expand_const_vector (rtx target, rtx src)
+{
+  machine_mode mode = GET_MODE (target);
+  rtx result = register_operand (target, mode) ? target : gen_reg_rtx (mode);
+  rtx elt;
+
+  if (const_vec_duplicate_p (src, &elt))
+    return expand_const_vec_duplicate (target, src, elt);
+
   /* Support scalable const series vector.  */
   rtx base, step;
   if (const_vec_series_p (src, &base, &step))