[clang] [llvm] [LTOBackend] Add -filter-print-modules= for save-temps to only dump specific modules. (PR #175696)

[Teresa Johnson via cfe-commits]

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@@ -0,0 +1,47 @@
+# RUN: rm -rf %t.dir
+# RUN: split-file %s %t.dir && cd %t.dir
+# RUN: %clang -c -flto=thin -O2  mymul.cpp  -o mymul.o
+# RUN: %clang -c -flto=thin -O2  myfoo.cpp  -o myfoo.o
+# RUN: %clang -fuse-ld=lld -shared -O2 -flto=thin mymul.o myfoo.o -o libmy.so -Wl,-plugin-opt=save-temps -Wl,-plugin-opt=-filter-print-modules=mymul.o
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teresajohnson wrote:

Since the change is purely in LLVM, use an LLVM LTO test not a clang test. For example, see llvm/test/ThinLTO/X86/selective-save-temps.ll, which is testing a different type of save-temps selectiveness.

https://github.com/llvm/llvm-project/pull/175696