[clang] [CIR] Upstream support for range-based for loops (PR #138176)

[Erich Keane via cfe-commits]

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@@ -190,6 +190,117 @@ void l3() {
 // OGCG:   store i32 0, ptr %[[I]], align 4
 // OGCG:   br label %[[FOR_COND]]
 
+void l4() {
+  int a[10];
+  for (int n : a)
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erichkeane wrote:

Can we do a test with a type with `begin` and `end` as well?  Or cant we support general iterators yet?

https://github.com/llvm/llvm-project/pull/138176