2e5989e814
Previously by default, when not using `--ifc=`, lld would not deduplicate string literals. This reveals reliance on undefined behavior where string literal addresses are compared instead of using string equality checks. While ideally you would be able to easily identify and eliminate the reliance on this UB, this can be difficult, especially for third party code, and increases the friction and risk of users migrating to lld. This flips the default to deduplicate strings unless `--no-deduplicate-strings` is passed, matching ld64's behavior. Differential Revision: https://reviews.llvm.org/D140517
45 lines
1.3 KiB
ArmAsm
45 lines
1.3 KiB
ArmAsm
# REQUIRES: aarch64
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# RUN: rm -rf %t; split-file %s %t
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# RUN: llvm-mc -filetype=obj -triple=arm64-apple-darwin %t/strings.s -o %t/strings.o
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# RUN: llvm-mc -filetype=obj -triple=arm64-apple-darwin %t/main.s -o %t/main.o
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# RUN: %lld -arch arm64 -lSystem -o %t.out %t/strings.o %t/main.o --no-deduplicate-strings
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# RUN: llvm-otool -vs __TEXT __cstring %t.out | FileCheck %s --check-prefix=CSTRING
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# RUN: llvm-otool -vs __TEXT __objc_methname %t.out | FileCheck %s --check-prefix=METHNAME
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# RUN: %lld -arch arm64 -lSystem -o %t/duplicates %t/strings.o %t/strings.o %t/main.o
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# RUN: llvm-otool -vs __TEXT __cstring %t/duplicates | FileCheck %s --check-prefix=CSTRING
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# RUN: llvm-otool -vs __TEXT __objc_methname %t/duplicates | FileCheck %s --check-prefix=METHNAME
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# CSTRING: Contents of (__TEXT,__cstring) section
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# CSTRING-NEXT: existing-cstring
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# CSTIRNG-EMPTY:
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# METHNAME: Contents of (__TEXT,__objc_methname) section
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# METHNAME-NEXT: existing_methname
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# METHNAME-NEXT: synthetic_methname
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# METHNAME-EMPTY:
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#--- strings.s
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.cstring
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.p2align 2
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.asciz "existing-cstring"
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.section __TEXT,__objc_methname,cstring_literals
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.asciz "existing_methname"
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#--- main.s
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.text
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.globl _objc_msgSend
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_objc_msgSend:
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ret
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.globl _main
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_main:
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bl _objc_msgSend$existing_methname
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bl _objc_msgSend$synthetic_methname
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ret
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