llvm-project

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# REQUIRES: x86
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# RUN: llvm-mc -filetype=obj -triple=x86_64-apple-macos %s -o %t.o
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# RUN: %lld -lSystem -dead_strip -why_live _foo -why_live _undef -U _undef \
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# RUN:   -why_live _support -why_live _support_refs_dylib_fun \
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# RUN:   -why_live _abs %t.o -o /dev/null 2>&1 | FileCheck %s
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## Due to an implementation detail, LLD is not able to report -why_live info for
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## absolute symbols. (ld64 has the same shortcoming.)
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# CHECK-NOT:   _abs
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# CHECK:       _foo from {{.*}}why-live.s.tmp.o
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# CHECK-NEXT:    _quux from {{.*}}why-live.s.tmp.o
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# CHECK-NEXT:  _undef from {{.*}}why-live.s.tmp.o
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# CHECK-NEXT:    _main from {{.*}}why-live.s.tmp.o
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## Our handling of live_support sections can be improved... we should print the
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## dylib symbol that keeps _support_refs_dylib_fun alive, instead of printing
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## the live_support symbol's name itself. (ld64 seems to have the same issue.)
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# CHECK-NEXT: _support_refs_dylib_fun from {{.*}}why-live.s.tmp.o
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# CHECK-NEXT:   _support_refs_dylib_fun from {{.*}}why-live.s.tmp.o
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## Again, this can be improved: we shouldn't be printing _support twice. (ld64
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## seems to have the same issue.)
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# CHECK-NEXT:  _support from {{.*}}why-live.s.tmp.o
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# CHECK-NEXT:    _support from {{.*}}why-live.s.tmp.o
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# CHECK-NEXT:      _foo from {{.*}}why-live.s.tmp.o
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# CHECK-EMPTY:
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.text
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_foo:
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  retq
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_bar:
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  retq
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_baz:
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  callq _foo
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  retq
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.no_dead_strip _quux
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_quux:
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  callq _foo
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  retq
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.globl _main
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_main:
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  callq _foo
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  callq _baz
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  callq _undef
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  callq ___isnan
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  retq
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.globl _abs
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_abs = 0x1000
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.section __TEXT,support,regular,live_support
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_support:
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  callq _foo
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  callq _abs
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  retq
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_support_refs_dylib_fun:
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  callq ___isnan
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  retq
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.subsections_via_symbols
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