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34 lines
887 B
ArmAsm
34 lines
887 B
ArmAsm
/* https://cirosantilli.com/linux-kernel-module-cheat#arm-adr-instruction */
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#include <lkmc.h>
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.data
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data_label:
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.word 0x1234678
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LKMC_PROLOGUE
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adr r4, .Llabel
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/* objdump tells us that this uses the literal pool,
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* it does not get converted to adr, which is the better
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* alternative here.
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*/
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ldr r5, =.Llabel
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adrl r6, .Llabel
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.Llabel:
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LKMC_ASSERT_EQ_REG(r4, r5)
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LKMC_ASSERT_EQ_REG(r4, r6)
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#if 0
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/* Error: symbol .data is in a different section.
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*
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* It works however in ARMv8.
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* I think this means that there is no relocation type
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* that takes care of this encoding in ARMv8, but there
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* is one in ARMv8.
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*
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* If you have no idea what I'm talking about, read this:
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* https://stackoverflow.com/questions/3322911/what-do-linkers-do/33690144#33690144
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*/
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adr r5, data_label
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#endif
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LKMC_EPILOGUE
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