[llvm] [RISCV][P-ext] Add splat_vector for 64-bit vectors on RV32. (PR #197345)

[Craig Topper via llvm-commits]

================
@@ -1902,21 +1874,8 @@ define <2 x i32> @test_non_const_splat_i32(i32 %elt) {
 define <8 x i8> @test_padd_bs_splat_lhs(<8 x i8> %a, i8 %b) {
 ; RV32-LABEL: test_padd_bs_splat_lhs:
 ; RV32:       # %bb.0:
-; RV32-NEXT:    addi sp, sp, -16
-; RV32-NEXT:    .cfi_def_cfa_offset 16
-; RV32-NEXT:    sb a2, 12(sp)
-; RV32-NEXT:    sb a2, 13(sp)
-; RV32-NEXT:    sb a2, 14(sp)
-; RV32-NEXT:    sb a2, 15(sp)
-; RV32-NEXT:    sb a2, 8(sp)
-; RV32-NEXT:    sb a2, 9(sp)
-; RV32-NEXT:    sb a2, 10(sp)
-; RV32-NEXT:    sb a2, 11(sp)
-; RV32-NEXT:    lw a3, 12(sp)
-; RV32-NEXT:    lw a2, 8(sp)
+; RV32-NEXT:    pmv.dbs a2, a2
 ; RV32-NEXT:    padd.db a0, a2, a0
----------------
topperc wrote:

I will fold this to padd.dbs in a follow up

https://github.com/llvm/llvm-project/pull/197345