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67 lines
1.4 KiB
ArmAsm
67 lines
1.4 KiB
ArmAsm
# thumb_blx_out_of_range.s
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# Test THUMB/THUMB-2 blx instructions just out of the branch range limits.
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.syntax unified
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.section .text.pre,"x"
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# Add padding so that target is just output of branch range.
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.space 4
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.global _forward_target
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.global _backward_target
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.type _backword_target, %function
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_backward_target:
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bx lr
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.size _backward_target, .-_backward_target
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.text
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# Use 256-byte alignment so that we know where the stubs start.
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.align 8
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# Define _start so that linker does not complain.
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.align 2
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.global _start
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.code 32
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.type _start, %function
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_start:
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bx lr
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.size _start, .-_start
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.global _backward_test
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.code 16
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.thumb_func
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.type _backward_test, %function
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_backward_test:
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bl _backward_target
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.size _backward_test, .-_backward_test
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.align 2
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.global _forward_test
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.code 16
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.thumb_func
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.type _forward_test, %function
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_forward_test:
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# Bit 1 of the BLX target comes from bit 1 of branch base address,
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# which is BLX instruction's address + 4. We intentionally put this
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# forward BLX at an address n*4 + 2 so that the branch offset is
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# bumped up by 2.
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nop.n
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bl _forward_target
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.size _forward_test, .-_forward_test
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# switch back to ARM mode so that stubs are disassembled correctly.
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.code 32
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nop
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.section .text.post,"x"
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# Add padding so that target is just out of branch range.
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.space 12
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.align 2
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.code 32
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.global _forward_target
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.type _forward_target, %function
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_forward_target:
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bx lr
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.size _forward_target, .-_forward_target
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