[llvm] [BOLT] Add support for safe-icf (PR #116275)

[Amir Ayupov via llvm-commits]

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@@ -0,0 +1,155 @@
+## Check that BOLT handles correctly folding functions with --icf=safe
+## that can be referenced through a non control flow instruction when ICP optimization is enabled.
+## This tests also checks that destructors are not folded.
+
+# REQUIRES: system-linux
+# RUN: llvm-mc -filetype=obj -triple x86_64-unknown-linux %s -o %t1.o
+# RUN: %clang %cflags %t1.o -o %t.exe -Wl,-q
+# RUN: llvm-bolt --no-threads %t.exe --icf      -debug -debug-only=bolt-icf -o %t.bolt 2>&1 | FileCheck --check-prefix=ICFCHECK %s
+# RUN: llvm-bolt --no-threads %t.exe --icf=safe -debug -debug-only=bolt-icf -o %t.bolt 2>&1 | FileCheck --check-prefix=SAFEICFCHECK %s
+
+# ICFCHECK:      ICF iteration 1
+# ICFCHECK-NEXT: folding _ZN8Derived3D0Ev into _ZN8Derived2D0Ev
+# ICFCHECK-NEXT: folding _ZNK8Derived34funcEii into _ZNK8Derived24funcEii
+
+# SAFEICFCHECK: skipping function _ZNK8Derived34funcEii
+# SAFEICFCHECK-NEXT: ICF iteration 1
+# SAFEICFCHECK-NEXT: folding _ZN8Derived3D0Ev into _ZN8Derived2D0Ev
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aaupov wrote:

Doesn't it contradict this statement at the top?
> This tests also checks that destructors are not folded.

nit: demangle names so it's explicit these are destructors (if it's important)

https://github.com/llvm/llvm-project/pull/116275