[llvm-branch-commits] [llvm] PeepholeOpt: Fix looking for def of current copy to coalesce (PR #125533)

[Pengcheng Wang via llvm-branch-commits]

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@@ -1891,31 +1886,44 @@ define <32 x i64> @vp_cttz_v32i64(<32 x i64> %va, <32 x i1> %m, i32 zeroext %evl
 ; RV32-NEXT:    addi a0, a0, 48
 ; RV32-NEXT:    vl8r.v v16, (a0) # Unknown-size Folded Reload
 ; RV32-NEXT:    vand.vv v16, v24, v16, v0.t
-; RV32-NEXT:    vsub.vv v24, v8, v16, v0.t
+; RV32-NEXT:    vsub.vv v8, v8, v16, v0.t
 ; RV32-NEXT:    csrr a0, vlenb
-; RV32-NEXT:    slli a0, a0, 5
+; RV32-NEXT:    li a1, 40
+; RV32-NEXT:    mul a0, a0, a1
 ; RV32-NEXT:    add a0, sp, a0
 ; RV32-NEXT:    addi a0, a0, 48
-; RV32-NEXT:    vl8r.v v8, (a0) # Unknown-size Folded Reload
-; RV32-NEXT:    vand.vv v16, v24, v8, v0.t
+; RV32-NEXT:    vs8r.v v8, (a0) # Unknown-size Folded Spill
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wangpc-pp wrote:

For RISCV, this is a regerssion since it requires more spill/reload.

https://github.com/llvm/llvm-project/pull/125533