[llvm] [NVPTX] Remove `NVPTX::IMAD` opcode, and rely on intruction selection only (PR #121724)

[Matt Arsenault via llvm-commits]

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@@ -7217,8 +7217,7 @@ void SelectionDAG::canonicalizeCommutativeBinop(unsigned Opcode, SDValue &N1,
 SDValue SelectionDAG::getNode(unsigned Opcode, const SDLoc &DL, EVT VT,
                               SDValue N1, SDValue N2, const SDNodeFlags Flags) {
   assert(N1.getOpcode() != ISD::DELETED_NODE &&
-         N2.getOpcode() != ISD::DELETED_NODE &&
-         "Operand is DELETED_NODE!");
+         N2.getOpcode() != ISD::DELETED_NODE && "Operand is DELETED_NODE!");
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arsenm wrote:

Only leftover unrelated formatting changes in this file 

https://github.com/llvm/llvm-project/pull/121724