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65 lines
1.3 KiB
ArmAsm
65 lines
1.3 KiB
ArmAsm
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# thumb_blx_in_range.s
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#
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# Test THUMB/THUMB-2 blx instructions just within the branch range limits.
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# Because bit 1 of the branch target comes from the branch instruction
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# address, the branch range from PC (branch instruction address + 4) is
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# acutally -((1<<22) + 2) to ((1<<22) - 4) for THUMB and -((1<<24) + 2) to
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# ((1<<24) - 4) from THUMB2.
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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 in branch range.
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.space 8
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.align 2
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.global _backward_target
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.code 32
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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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# Define _start so that linker does not complain.
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.global _start
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.code 32
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.align 2
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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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nop.n
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blx _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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blx _forward_target
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.size _forward_test, .-_forward_test
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.code 32
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.section .text.post,"x"
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# Add padding so that target is just in branch range.
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.space 12
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.align 2
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.global _forward_target
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.code 32
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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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