[llvm] [LLVM][AArch64InstrInfo] Prevent fill folding when DstReg is SP. (PR #148885)

[Paul Walker via llvm-commits]

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@@ -121,6 +122,24 @@ body:             |
     RET_ReallyLR implicit $s0
 ...
 ---
+# CHECK-LABEL: name: test_subreg_fill_fold4
+# Ensure the COPY is maintained when its result register class is not compatible
+# with the fill load's.
+name:            test_subreg_fill_fold4
+registers:
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paulwalker-arm wrote:

This is a clone of `test_subreg_fill_fold` with just the register class of `%1` changed from `gpr64` to `gpr64sp`.

https://github.com/llvm/llvm-project/pull/148885