[llvm] [PowerPC] Add bctar instruction (ISA 2.07) (PR #187322)

[Lei Huang via llvm-commits]

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@@ -5256,17 +5290,40 @@ multiclass BranchSimpleMnemonic2<string name, string pm, int bo>
   def : InstAlias<"b"#name#"ctr"#pm#" $bi", (gBCCTR bo, crbitrc:$bi, 0)>;
   def : InstAlias<"b"#name#"ctrl"#pm#" $bi", (gBCCTRL bo, crbitrc:$bi, 0)>;
 }
-defm : BranchSimpleMnemonic2<"t", "", 12>;
-defm : BranchSimpleMnemonic2<"f", "", 4>;
-defm : BranchSimpleMnemonic2<"t", "-", 14>;
-defm : BranchSimpleMnemonic2<"f", "-", 6>;
-defm : BranchSimpleMnemonic2<"t", "+", 15>;
-defm : BranchSimpleMnemonic2<"f", "+", 7>;
+multiclass BranchSimpleMnemonic3<string name, string pm, int bo>
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lei137 wrote:

Do we really need this new multiclass?  Seems this makes BranchSimpleMnemonic2 obsolete so maybe just add the def directly into BranchSimpleMnemonic2?

https://github.com/llvm/llvm-project/pull/187322