[llvm] [NFC] Fixed test case fail caused by the patch [SelectionDAG] Folding ZERO-EXTEND/SIGN_EXTEND poison to Poison value in getNode #122741 (PR #136636)

[Phoebe Wang via llvm-commits]

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@@ -8,18 +8,19 @@ target triple = "x86_64-unknown-linux-gnu"
 define void @func() {
 ; CHECK-LABEL: func:
 ; CHECK:       # %bb.0: # %bb1
-; CHECK-NEXT:    xorl %eax, %eax
 ; CHECK-NEXT:    testb %al, %al
 ; CHECK-NEXT:    je .LBB0_1
 ; CHECK-NEXT:  # %bb.3: # %L_30
 ; CHECK-NEXT:    retq
-; CHECK-NEXT:  .LBB0_1: # %bb56
-; CHECK-NEXT:    xorl %eax, %eax
 ; CHECK-NEXT:    .p2align 4
-; CHECK-NEXT:  .LBB0_2: # %bb33
-; CHECK-NEXT:    # =>This Inner Loop Header: Depth=1
-; CHECK-NEXT:    testb %al, %al
-; CHECK-NEXT:    jmp .LBB0_2
+; CHECK-NEXT:  .LBB0_1: # %bb33
+; CHECK-NEXT:   # =>This Inner Loop Header: Depth=1
+; CHECK-NEXT:    testb   %al, %al
+; CHECK-NEXT:    jne     .LBB0_1
+; CHECK-NEXT:  # %bb.2:                                # %bb35
+; CHECK-NEXT:  #   in Loop: Header=BB0_1 Depth=1
+; CHECK-NEXT:    testb   %al, %al
+; CHECK-NEXT:    jmp     .LBB0_1
 bb1:
   br i1 poison, label %L_10, label %L_10
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phoebewang wrote:

I see a lot of such code in the tests. It's hard to tell if the initial tested assemble affected or not.

How about modify `br i1 poison` to `br i1 %c0,1,2,...` which `%c0,1,2` come from arguments. Then it would be an NFC patch.

https://github.com/llvm/llvm-project/pull/136636