[llvm] [RISCV] Use BuildPairF64 and SplitF64 for bitcast i64<->f64 on rv32 regardless of Zfa. (PR #85982)

[Wang Pengcheng via llvm-commits]

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@@ -804,13 +804,15 @@ define double @fill_i64_to_double(i64 %a) nounwind {
 ; RV32ID-NEXT:    fsd fs9, 40(sp) # 8-byte Folded Spill
 ; RV32ID-NEXT:    fsd fs10, 32(sp) # 8-byte Folded Spill
 ; RV32ID-NEXT:    fsd fs11, 24(sp) # 8-byte Folded Spill
-; RV32ID-NEXT:    sw a1, 20(sp)
-; RV32ID-NEXT:    sw a0, 16(sp)
-; RV32ID-NEXT:    fld fa5, 16(sp)
-; RV32ID-NEXT:    fsd fa5, 8(sp) # 8-byte Folded Spill
+; RV32ID-NEXT:    sw a1, 12(sp) # 4-byte Folded Spill
+; RV32ID-NEXT:    sw a0, 8(sp) # 4-byte Folded Spill
 ; RV32ID-NEXT:    #APP
 ; RV32ID-NEXT:    #NO_APP
-; RV32ID-NEXT:    fld fa0, 8(sp) # 8-byte Folded Reload
+; RV32ID-NEXT:    lw a0, 8(sp) # 4-byte Folded Reload
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wangpc-pp wrote:

This is a regression?

https://github.com/llvm/llvm-project/pull/85982