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https://github.com/cirosantilli/linux-kernel-module-cheat.git
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59 lines
1.1 KiB
ArmAsm
59 lines
1.1 KiB
ArmAsm
/* https://cirosantilli.com/linux-kernel-module-cheat#arm-data-processing-instructions */
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#include <lkmc.h>
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LKMC_PROLOGUE
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/* Immediate encoding.
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*
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* r1 = r0 + 2
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*/
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mov r0, 1
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/* r1 = r0 + 2 */
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add r1, r0, 2
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LKMC_ASSERT_EQ(r1, =3)
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/* If src == dest, we can omit one of them.
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*
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* r0 = r0 + 2
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*/
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mov r0, 1
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add r0, 2
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LKMC_ASSERT_EQ(r0, =3)
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/* Same as above but explicit. */
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mov r0, 1
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add r0, r0, 2
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LKMC_ASSERT_EQ(r0, =3)
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#if 0
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/* But we cannot omit the register if there is a shift when using .syntx unified:
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* https://cirosantilli.com/linux-kernel-module-cheat#arm-shift-suffixes
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*/
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.syntax unified
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/* Error: garbage following instruction */
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add r0, r1, lsl 1
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/* OK */
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add r0, r0, r1, lsl 1
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#endif
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/* Register encoding.
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*
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* r2 = r0 + r1
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*/
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mov r0, 1
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mov r1, 2
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add r2, r0, r1
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LKMC_ASSERT_EQ(r2, =3)
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/* Register encoding, omit implicit register.
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*
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* r1 = r1 + r0
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*/
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mov r0, 1
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mov r1, 2
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add r1, r0
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LKMC_ASSERT_EQ(r1, =3)
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LKMC_EPILOGUE
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