[llvm] [SCCP] Refine trunc with nsw/nuw flags (PR #87926)

[Yingwei Zheng via llvm-commits]

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@@ -146,6 +146,21 @@ static bool refineInstruction(SCCPSolver &Solver,
       Inst.setNonNeg();
       Changed = true;
     }
+  } else if (TruncInst *TI = dyn_cast<TruncInst>(&Inst)) {
+    auto Range = GetRange(Inst.getOperand(0));
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dtcxzyw wrote:

We can avoid computing ranges if both flags are already set. Same for `OverflowingBinaryOperator`.


https://github.com/llvm/llvm-project/pull/87926