[lld] [lld] handle re-exports for full framework paths (PR #137989)

[Richard Howell via llvm-commits]

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@@ -1566,6 +1566,25 @@ static DylibFile *loadDylib(StringRef path, DylibFile *umbrella) {
   return loadDylib(*mbref, umbrella);
 }
 
+static StringRef findFramework(StringRef path, StringRef frameworkName) {
+  // Framework names can be in multiple formats:
+  // - Foo.framework/Foo
+  // - Foo.framework/Versions/A/Foo
+  size_t start;
+  size_t end = path.size();
+  while (true) {
+    start = path.rfind('/', end);
+    if (start == StringRef::npos)
+      return StringRef();
+
+    StringRef component = path.substr(start + 1, end - start - 1);
+    if (component == frameworkName)
+      return path.substr(start + 1);
+
+    end = start;
+  }
----------------
rmaz wrote:

Not sure why I didn't do that, think because I was using path iterators and then gave up on the approach.

One issue with this is it would incorrectly return a substring for `Foo.framework` if path was `/Some/Path/OtherFoo.framework/...`, but could be handled by checking the previous char. Either that or check if the string starts with the pattern or has `/Foo.framework/`

https://github.com/llvm/llvm-project/pull/137989