ef232a7e34
When a function has an indirect branch with unknown control flow, we preserve nops in order to keep all instruction offsets (from the start of the function) the same in case the indirect branch is used by a PC-relative jump table. However, when we know the control flow of the function, we should be able to safely remove nops.
29 lines
801 B
ArmAsm
29 lines
801 B
ArmAsm
## Verify that llvm-bolt removes nop instructions from functions with indirect
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## branches that have defined control flow.
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# REQUIRES: system-linux
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# RUN: llvm-mc -filetype=obj -triple aarch64-unknown-unknown %s -o %t.o
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# RUN: %clang %cflags --target=aarch64-unknown-linux %t.o -o %t.exe -Wl,-q
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# RUN: llvm-bolt %t.exe -o %t.bolt --print-normalized 2>&1 | FileCheck %s
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# RUN: llvm-objdump -d --disassemble-symbols=_start %t.bolt \
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# RUN: | FileCheck %s --check-prefix=CHECK-OBJDUMP
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# CHECK-OBJDUMP-LABEL: _start
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# CHECK-OBJDUMP-NOT: nop
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.section .text
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.align 4
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.globl _start
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.type _start, %function
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_start:
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# CHECK-LABEL: Binary Function "_start"
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nop
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# CHECK-NOT: nop
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br x0
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# CHECK: br x0 # TAILCALL
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.size _start, .-_start
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## Force relocation mode.
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.reloc 0, R_AARCH64_NONE
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