[clang] [llvm] [clang][CodeGen] Generate follow-up metadata for loops in correct format (PR #131985)

[Michael Kruse via llvm-commits]

================
@@ -44,23 +44,19 @@ MDNode *LoopInfo::createPipeliningMetadata(const LoopAttributes &Attrs,
   else if (Attrs.PipelineInitiationInterval != 0)
     Enabled = true;
 
+  SmallVector<Metadata *, 4> Args;
+  Args.append(LoopProperties.begin(), LoopProperties.end());
+
   if (Enabled != true) {
-    SmallVector<Metadata *, 4> NewLoopProperties;
     if (Enabled == false) {
-      NewLoopProperties.append(LoopProperties.begin(), LoopProperties.end());
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Meinersbur wrote:

I think this is due to the regex `.*` being too greedy, so e.g. `![[ISVECTORIZED:.*]]` consumes multiple metadata nodes. A better one would be `[_a-zA-Z0-9.]+`. In principle `![[ISVECTORIZED]] = {!"llvm.loop.isvectorized"}` (or `UNROLL_8`) should be verified somewhere, which would then fail if it matched more than one node.

IMHO there are lots of problems with FileCheck on LLVM-IR, and this is just one of them. Another one is that by default `CHECK: car sale` will match `carpet sale`.

https://github.com/llvm/llvm-project/pull/131985