[llvm] [llvm-objcopy] Add --skip-symbol and --skip-symbols options (PR #80873)

[James Henderson via llvm-commits]

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@@ -0,0 +1,78 @@
+# RUN: yaml2obj %s -o %t.o
+# RUN: echo 'foo[2-3]' > %t.skip.regex
+
+## Check --skip-symbols functionality when changing symbol bindings.
+# RUN: llvm-objcopy %t.o %t1.o --localize-hidden --skip-symbols=%t.skip.regex --regex
+# RUN: llvm-readelf -s %t1.o | FileCheck %s --check-prefix=LH-SYMS
+# LH-SYMS-DAG: LOCAL  HIDDEN      1 foo1
+# LH-SYMS-DAG: GLOBAL HIDDEN      1 foo2
+# LH-SYMS-DAG: GLOBAL HIDDEN      1 foo3
+
+## Check --skip-symbol functionality when changing symbol bindings.
+# RUN: llvm-objcopy %t.o %t2.o --localize-hidden --skip-symbol=foo3
+# RUN: llvm-readelf -s %t2.o | FileCheck %s --check-prefix=LH-SYM
+# LH-SYM-DAG: LOCAL  HIDDEN      1 foo1
+# LH-SYM-DAG: LOCAL  HIDDEN      1 foo2
+# LH-SYM-DAG: GLOBAL HIDDEN      1 foo3
+
+## Check --skip-symbols functionality when changing symbol names.
+# RUN: echo -e "foo1 bar1\nfoo2 bar2" > %t.renames.list
+# RUN: llvm-objcopy %t.o %t3.o --redefine-syms=%t.renames.list \
+# RUN:   --skip-symbols=%t.skip.regex --regex
+# RUN: llvm-readelf -s %t3.o | FileCheck %s --check-prefix=RS-SYMS
+# RS-SYMS-DAG: bar1
+# RS-SYMS-DAG: foo2
+# RS-SYMS-DAG: foo3
+
+## Check --skip-symbol functionality when changing symbol names.
+# RUN: llvm-objcopy %t.o %t4.o --redefine-sym=foo1=bar1 --skip-symbol='fo*' --wildcard
+# RUN: llvm-readelf -s %t4.o | FileCheck %s --check-prefix=RS-SYM
+# RS-SYM-DAG: foo1
+# RS-SYM-DAG: foo2
+# RS-SYM-DAG: foo3
+
+## Check the functionality when using skip options multiple times.
+# RUN: echo "foo3" > %t.symbol.list
+# RUN: llvm-objcopy %t.o %t5.o --set-symbol-visibility='foo*'=internal --wildcard \
+# RUN:   --skip-symbol=foo1 --skip-symbol=foo2 --skip-symbols=%t.symbol.list
+# RUN: llvm-readelf -s %t5.o | FileCheck %s --check-prefix=BOTH
+## All the symbols are skipped
+# BOTH-DAG: GLOBAL HIDDEN      1 foo1
+# BOTH-DAG: GLOBAL HIDDEN      1 foo2
+# BOTH-DAG: GLOBAL HIDDEN      1 foo3
+
+## Check that using an invalid symbol pattern generates an error.
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jh7370 wrote:

For clarity, I'd change "symbol pattern" to "regex" or possibly "symbol name regex".

https://github.com/llvm/llvm-project/pull/80873