[llvm] [MemProf] Add dot graph dumping immediately after stack node update (PR #143025)

[Snehasish Kumar via llvm-commits]

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@@ -6,11 +6,20 @@
 ; REQUIRES: asserts
 
 ; RUN: opt -passes=memprof-context-disambiguation -supports-hot-cold-new \
+; RUN:	-memprof-export-to-dot -memprof-dot-file-path-prefix=%t. \
 ; RUN:  -stats -debug %s -S 2>&1 | FileCheck %s --check-prefix=STATS \
 ; RUN:  --check-prefix=IR --check-prefix=DEBUG
 
 ; DEBUG: Not found through unique tail call chain: _Z3barv from main that actually called xyz (found multiple possible chains)
 
+;; Graph fixup should have nulled the call in the node that could not be
+;; resolved via tail call fixup. That happens in between the initial
+;; stack update and the end of graph building.
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snehasish wrote:

nit: "and at the end"?

https://github.com/llvm/llvm-project/pull/143025