[lld] [LLD] Improve linker script handing in LLD (PR #106334)

[Daniel Thornburgh via llvm-commits]

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@@ -131,6 +131,156 @@ uint64_t ExprValue::getSectionOffset() const {
   return getValue() - getSecAddr();
 }
 
+std::function<ExprValue()> ScriptExpr::getExpr() const {
+  switch (kind_) {
+  case ExprKind::Constant:
+    return static_cast<const ConstantExpr *>(this)->getConstantExpr();
+  case ExprKind::Dynamic: {
+    auto expr = static_cast<const DynamicExpr *>(this);
+    return expr->getImpl();
+  }
+  case ExprKind::Binary: {
+    auto expr = static_cast<const BinaryExpr *>(this);
+    return [=] { return expr->evaluateBinaryOperands(); };
+  }
+  default:
+    return [] { return ExprValue(0); };
+  };
+}
+
+ExprValue ScriptExpr::getExprValue() const {
+  switch (kind_) {
+  case ExprKind::Constant:
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mysterymath wrote:

Each of the functions called on the derived classes should be named `getExprValue()`. This minimizes the amount of information about the implementations of the various expression subclasses present in the base class.

https://github.com/llvm/llvm-project/pull/106334