[llvm] [llvm-objcopy] Add --remove-symbol-prefix (PR #79415)

[James Henderson via llvm-commits]

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@@ -0,0 +1,64 @@
+# RUN: yaml2obj %s -o %t
+# RUN: llvm-objcopy --remove-symbol-prefix __pf_ %t %t2
+# RUN: llvm-readelf --symbols %t2 | FileCheck %s
+
+## Show that an empty string is permitted as the argument to
+## --remove-prefix-symbols.
+# RUN: llvm-objcopy --remove-symbol-prefix= %t2 %t3
+# RUN: cmp %t2 %t3
+
+## When both options are present, llvm-objcopy should remove
+## prefixes first, before adding prefixes.
+# RUN: llvm-objcopy --remove-symbol-prefix=AAA --prefix-symbols=AAA %t %t4
+# RUN: llvm-objcopy --prefix-symbols=AAA %t %t5
+# RUN: cmp %t4 %t5
+
+## Show that the last --remove-symbol-prefix option wins.
+# RUN: llvm-objcopy --remove-symbol-prefix=__pf_ --remove-symbol-prefix=__ %t %6
+# RUN: llvm-objcopy --remove-symbol-prefix=__ %t %7
+# RUN: cmp %6 %7
+
+!ELF
+FileHeader:
+  Class:           ELFCLASS64
+  Data:            ELFDATA2LSB
+  Type:            ET_REL
+  Machine:         EM_X86_64
+Sections:
+  - Name:            .text
+    Type:            SHT_PROGBITS
+    Flags:           [ SHF_ALLOC, SHF_EXECINSTR ]
+    Address:         0x1000
+    AddressAlign:    0x0000000000000010
+    Size:            64
+Symbols:
+  - Name:     __pf_foo
+    Type:     STT_SECTION
+    Section:  .text
+  - Name:     __pf_bar
+    Type:     STT_FILE
+    Section:  .text
+  - Name:     foobar
+    Type:     STT_FUNC
+    Section:  .text
+    Binding:  STB_GLOBAL
+  - Name:     foo__pf_bar1
+    Type:     STT_FUNC
+    Section:  .text
+    Binding:  STB_GLOBAL
+  - Name:     __pf_foo__pf_bar2
+    Type:     STT_FUNC
+    Section:  .text
+    Binding:  STB_GLOBAL
+  - Name:     undef
+    Binding:  STB_GLOBAL
+
+# CHECK:      Symbol table '.symtab' contains [[#]] entries:
----------------
jh7370 wrote:

I don't see any reason to not match the exact number of symbols here, so replace this `[[#]]` with 7.

https://github.com/llvm/llvm-project/pull/79415