[llvm] [NVPTX] Cleanup various vestigial elements and fold together more table-gen (NFC) (PR #151447)

[Artem Belevich via llvm-commits]

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@@ -2335,32 +2199,20 @@ defm : CVT_ROUND<frint, CvtRNI, CvtRNI_FTZ>;
 //-----------------------------------
 
 let isTerminator=1 in {
-   let isReturn=1, isBarrier=1 in
+  let isReturn=1, isBarrier=1 in
       def Return : BasicNVPTXInst<(outs), (ins), "ret", [(retglue)]>;
 
-   let isBranch=1 in
-      def CBranch : NVPTXInst<(outs), (ins B1:$a, brtarget:$target),
+  let isBranch=1 in {
+    def CBranch : NVPTXInst<(outs), (ins B1:$a, brtarget:$target),
                               "@$a bra \t$target;",
                               [(brcond i1:$a, bb:$target)]>;
-   let isBranch=1 in
-      def CBranchOther : NVPTXInst<(outs), (ins B1:$a, brtarget:$target),
-                                   "@!$a bra \t$target;", []>;
 
-   let isBranch=1, isBarrier=1 in
+    let isBarrier=1 in
       def GOTO : BasicNVPTXInst<(outs), (ins brtarget:$target),
-                           "bra.uni", [(br bb:$target)]>;
+                            "bra.uni", [(br bb:$target)]>;
+  }
 }
 
-def : Pat<(brcond i32:$a, bb:$target),
-          (CBranch (SETP_i32ri $a, 0, CmpNE), bb:$target)>;
-
-// SelectionDAGBuilder::visitSWitchCase() will invert the condition of a
-// conditional branch if the target block is the next block so that the code
-// can fall through to the target block.  The inversion is done by 'xor
-// condition, 1', which will be translated to (setne condition, -1).  Since ptx
-// supports '@!pred bra target', we should use it.
-def : Pat<(brcond (i1 (setne i1:$a, -1)), bb:$target),
-          (CBranchOther $a, bb:$target)>;
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Artem-B wrote:

This sounds somewhat useful, but we may not have a good test for it.

How certain are you that we no longer need it?

https://github.com/llvm/llvm-project/pull/151447