[llvm] [RISCV] Partially move doPeepholeMaskedRVV into RISCVFoldMasks (PR #72441)

[Luke Lau via llvm-commits]

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@@ -151,6 +151,10 @@ void RISCVDAGToDAGISel::PostprocessISelDAG() {
       continue;
 
     MadeChange |= doPeepholeSExtW(N);
+
+    // FIXME: This is here only because the VMerge transform doesn't
+    // know how to handle masked true inputs.  Once that has been moved
+    // to post-ISEL, this can be deleted as well.
     MadeChange |= doPeepholeMaskedRVV(cast<MachineSDNode>(N));
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lukel97 wrote:

See also https://github.com/lukel97/llvm-project/blob/01854599f2cfd84899c37f4791d6c4a0784017e1/llvm/lib/Target/RISCV/RISCVFoldMasks.cpp#L521-L522

https://github.com/llvm/llvm-project/pull/72441