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#include "../../env/encoding.h"
#undef MCONTROL_TYPE
#undef MCONTROL_DMODE
#ifdef __riscv64
# define MCONTROL_TYPE (0xf<<(64-4))
# define MCONTROL_DMODE (1<<(64-5))
#else
# define MCONTROL_TYPE (0xf<<(32-4))
# define MCONTROL_DMODE (1<<(32-5))
#endif
.global main
.section .text
main:
la a0, data
li t0, 0
just_before_read_loop:
li t2, 16
read_loop:
lw t1, 0(a0)
addi t0, t0, 1
addi a0, a0, 4
blt t0, t2, read_loop
la a0, data
just_before_write_loop:
li t0, 1
write_loop:
sw t0, 0(a0)
addi t0, t0, 1
addi a0, a0, 4
blt t0, t2, write_loop
j main_exit
write_valid:
li t0, 0
li t2, MCONTROL_DMODE
li t3, MCONTROL_TYPE
write_valid_loop:
csrw CSR_TSELECT, t0
csrr t1, CSR_TSELECT
bne t0, t1, main_exit
addi t0, t0, 1
csrr t1, CSR_TDATA1
and t4, t1, t3
beqz t4, main_error # type is 0
and t1, t1, t2
bnez t1, write_valid_loop
# Found an entry with dmode=0
csrw CSR_TDATA1, zero # this should succeed
write_invalid:
li t0, 0
li t2, MCONTROL_DMODE
li t3, MCONTROL_TYPE
write_invalid_loop:
csrw CSR_TSELECT, t0
csrr t1, CSR_TSELECT
bne t0, t1, main_exit
addi t0, t0, 1
csrr t1, CSR_TDATA1
and t4, t1, t3
beqz t4, main_error # type is 0
and t1, t1, t2
beqz t1, write_invalid_loop
# Found an entry with dmode=1
write_invalid_illegal:
csrw CSR_TDATA1, zero # this should fail
main_exit:
li a0, 0
j _exit
main_error:
li a0, 1
j _exit
.data
data: .word 0x40
.word 0x41
.word 0x42
.word 0x43
.word 0x44
.word 0x45
.word 0x46
.word 0x47
.word 0x48
.word 0x49
.word 0x4a
.word 0x4b
.word 0x4c
.word 0x4d
.word 0x4e
.word 0x4f
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