[llvm] [RISCV] Fold extract_vector_elt of a load info the scalar load (PR #76151)

[Wang Pengcheng via llvm-commits]

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@@ -7,10 +7,7 @@
 define i8 @extractelt_v16i8(ptr %x) nounwind {
 ; CHECK-LABEL: extractelt_v16i8:
 ; CHECK:       # %bb.0:
-; CHECK-NEXT:    vsetivli zero, 16, e8, m1, ta, ma
-; CHECK-NEXT:    vle8.v v8, (a0)
-; CHECK-NEXT:    vslidedown.vi v8, v8, 7
-; CHECK-NEXT:    vmv.x.s a0, v8
+; CHECK-NEXT:    lbu a0, 7(a0)
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wangpc-pp wrote:

We may need to rework this test as there is no test coverage for some code of `lowerEXTRACT_VECTOR_ELT` anymore after your optimization.

https://github.com/llvm/llvm-project/pull/76151