[llvm] [CodeGen][GC] Skip function without GC in `GCLoweringPass` (PR #84421)

[Matt Arsenault via llvm-commits]

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@@ -0,0 +1,42 @@
+; RUN: opt -S -passes='require<collector-metadata>,function(gc-lowering)' < %s | FileCheck %s
+
+declare ptr @llvm_gc_allocate(i32)
+declare void @llvm_gc_initialize(i32)
+
+declare void @llvm.gcroot(ptr, ptr)
+declare void @llvm.gcwrite(ptr, ptr, ptr)
+
+define i32 @main() gc "shadow-stack" {
+entry:
+	%A = alloca ptr
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arsenm wrote:

test whitespace is weird 

https://github.com/llvm/llvm-project/pull/84421