[llvm] [SLP] NFC. Replace MainOp and AltOp in TreeEntry with InstructionsState. (PR #120198)

[Alexey Bataev via llvm-commits]

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@@ -3402,30 +3403,27 @@ class BoUpSLP {
       auto *I = dyn_cast<Instruction>(Op);
       if (I && isOpcodeOrAlt(I))
         return Op;
-      return MainOp;
+      return S.getMainOp();
     }
 
     void setOperations(const InstructionsState &S) {
       assert(S && "InstructionsState is invalid.");
-      MainOp = S.getMainOp();
-      AltOp = S.getAltOp();
+      this->S = S;
     }
 
-    Instruction *getMainOp() const {
-      return MainOp;
-    }
+    Instruction *getMainOp() const { return S.getMainOp(); }
 
-    Instruction *getAltOp() const {
-      return AltOp;
-    }
+    Instruction *getAltOp() const { return S.getAltOp(); }
 
     /// The main/alternate opcodes for the list of instructions.
-    unsigned getOpcode() const {
-      return MainOp ? MainOp->getOpcode() : 0;
-    }
+    unsigned getOpcode() const { return S.getOpcode(); }
 
-    unsigned getAltOpcode() const {
-      return AltOp ? AltOp->getOpcode() : 0;
+    unsigned getAltOpcode() const { return S.getAltOpcode(); }
+
+    bool isInstructionsStateValid() const {
+      assert((S.valid() || isGather()) &&
+             "Invalid InstructionsState must be gathered.");
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alexey-bataev wrote:

No need for assertion here

https://github.com/llvm/llvm-project/pull/120198