82 lines
1.8 KiB
ArmAsm
82 lines
1.8 KiB
ArmAsm
# This reproduces an issue where two fragments of same function access same
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# jump table, which means at least one fragment visits the other, i.e., one
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# of them has split jump table. As a result, all of them will be marked as
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# non-simple function.
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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 -print-cfg -v=3 %t.exe -o %t.out 2>&1 | FileCheck %s
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# CHECK: BOLT-INFO: Multiple fragments access same jump table: main; main.cold.1
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# CHECK: PIC Jump table JUMP_TABLE1 for function main, main.cold.1 at {{.*}} with a total count of 0:
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.text
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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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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_TABLE1(%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, .-main
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# cold fragment is only reachable
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.globl main.cold.1
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.type main.cold.1, %function
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.p2align 2
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main.cold.1:
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# load bearing nop: pad LBB8 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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andl $0xb, %ebx
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cmpb $0x1, %cl
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# exit through ret
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ja LBB7
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# jump table dispatch, jumping to label indexed by val in %ecx
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LBB5:
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leaq JUMP_TABLE1(%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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LBB6:
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xorq %rax, %rax
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LBB7:
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addq $0x8, %rsp
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ret
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LBB8:
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callq abort
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.size main.cold.1, .-main.cold.1
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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_TABLE1
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JUMP_TABLE1:
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.long LBB2-JUMP_TABLE1
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.long LBB3-JUMP_TABLE1
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.long LBB8-JUMP_TABLE1
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.long LBB6-JUMP_TABLE1
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.long LBB7-JUMP_TABLE1
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