67 lines
1.5 KiB
ArmAsm
67 lines
1.5 KiB
ArmAsm
# This reproduces a bug with jump table identification where jump table has
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# entries pointing to code in function and its cold fragment.
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# The fragment is only reachable through jump table.
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# REQUIRES: system-linux
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# RUN: llvm-mc -filetype=obj -triple x86_64-unknown-unknown %s -o %t.o
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# RUN: llvm-strip --strip-unneeded %t.o
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# RUN: %clang %cflags %t.o -o %t.exe -Wl,-q
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# RUN: llvm-bolt %t.exe -o %t.out --lite=0 -v=1 2>&1 | FileCheck %s
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# CHECK-NOT: unclaimed PC-relative relocations left in data
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# CHECK: BOLT-INFO: marking main.cold as a fragment of main
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.text
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.globl _start
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.type _start, %function
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_start:
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callq main.cold
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call exit
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.size _start, .-_start
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.globl main.cold
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.type main.cold, %function
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.p2align 2
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main.cold:
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LBB0:
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andl $0xf, %ecx
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cmpb $0x4, %cl
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# exit through ret
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ja LBB3
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# jump table dispatch, jumping to label indexed by val in %ecx
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LBB1:
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leaq JUMP_TABLE(%rip), %r8
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movzbl %cl, %ecx
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movslq (%r8,%rcx,4), %rax
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addq %rax, %r8
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jmpq *%r8
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LBB2:
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xorq %rax, %rax
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LBB3:
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addq $0x8, %rsp
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ret
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.size main.cold, .-main.cold
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# main function, referenced from jump table in cold fragment
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.globl main
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.type main, %function
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.p2align 2
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main:
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# load bearing nop: pad LBB4 so that it can't be treated
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# as __builtin_unreachable by analyzeJumpTable
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nop
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LBB4:
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callq abort
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.size main, .-main
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.rodata
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# jmp table, entries must be R_X86_64_PC32 relocs
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.globl JUMP_TABLE
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JUMP_TABLE:
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.long LBB2-JUMP_TABLE
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.long LBB3-JUMP_TABLE
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.long LBB4-JUMP_TABLE
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.long LBB3-JUMP_TABLE
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