[llvm] [X86][MC] Support 'ctestX <reg>, <mem>' and 'ctextX <mem>, <reg>' as synonyms. (PR #97985)

[Freddy Ye via llvm-commits]

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@@ -27,6 +27,19 @@
 # CHECK: ctestbq {dfv=of} %r9, 123(%r8,%rax,4)
 # CHECK: encoding: [0x62,0x54,0xc4,0x02,0x85,0x4c,0x80,0x7b]
          ctestbq {dfv=of} %r9, 123(%r8,%rax,4)
+# Swap mr form
+# CHECK: ctestbb {dfv=of} %bl, 123(%r8,%rax,4)
+# CHECK: encoding: [0x62,0xd4,0x44,0x02,0x84,0x5c,0x80,0x7b]
+         ctestbb {dfv=of} 123(%r8,%rax,4), %bl
+# CHECK: ctestbw {dfv=of} %dx, 123(%r8,%rax,4)
+# CHECK: encoding: [0x62,0xd4,0x45,0x02,0x85,0x54,0x80,0x7b]
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FreddyLeaf wrote:

Actually, I was intending to put them near the reverse forms above. From L18-29

https://github.com/llvm/llvm-project/pull/97985