[llvm] [llvm-objcopy] Add change-section-lma *+/-offset (PR #95431)

[James Henderson via llvm-commits]

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@@ -552,6 +552,38 @@ static Error loadNewSectionData(StringRef ArgValue, StringRef OptionName,
   return Error::success();
 }
 
+static Expected<int64_t> parseChangeSectionLMA(StringRef ArgValue,
+                                               StringRef OptionName) {
+  StringRef StringValue;
+  if (ArgValue.starts_with("*+")) {
+    StringValue = ArgValue.slice(2, StringRef::npos);
+  } else if (ArgValue.starts_with("*-")) {
+    StringValue = ArgValue.slice(1, StringRef::npos);
+  } else if (ArgValue.contains("=")) {
+    return createStringError(errc::invalid_argument,
+                             "bad format for " + OptionName +
+                                 ": changing LMA to a specific value is not "
+                                 "supported. Use *+val or *-val instead");
+  } else if (ArgValue.contains("+") || ArgValue.contains("-")) {
+    return createStringError(errc::invalid_argument,
+                             "bad format for " + OptionName +
+                                 ": changing a specific section LMA is not "
+                                 "supported. Use *+val or *-val instead");
+  }
+  if (StringValue.empty())
+    return createStringError(errc::invalid_argument,
+                             "bad format for " + OptionName +
+                                 ": missing LMA offset");
+
+  auto LMAValue = getAsInteger<int64_t>(StringValue);
+  if (!LMAValue)
+    return createStringError(LMAValue.getError(),
+                             "bad format for " + OptionName + ": value after " +
+                                 ArgValue.slice(0, 2) + " is " + StringValue +
+                                 " when it should be integer");
----------------
jh7370 wrote:

"an integer"

https://github.com/llvm/llvm-project/pull/95431