riscv.txt

double word 64bit
word 32bit

unsigned int %u
int %d
unsigned long long int %llu
long long int %lld

positive number -> invert -> +1 -> negtive number -> intert -> +1 -> positive number
cat <<EOF > ll.c
#include <stdio.h>
#include <math.h>
int main() {
    unsigned long long int llu_max = (unsigned long long int) (pow(2, 64) - 1);
    printf("highest number represented by unsigned long long int is %llu\n", llu_max);

    long long int lld_max = (long long int) (pow(2, 63) - 1);
    printf("highest number represented by signed long long int is %lld\n", lld_max);

    long long int lld_min = (long long int) (pow(2, 63) * -1);
    printf("lowest number represented by signed long long int is %lld\n", lld_min);

    return 0;
}
EOF

cat <<EOF >sum.c
#include <stdio.h>
int main() {
    int i, sum = 0, n = 100;
    for (i = 1; i <= n; ++i) {
        sum += i;
    }
    printf("Sum of numbers from 1 to %d is %d\n", n, sum);
    return 0;
}
EOF

gcc sum.c

riscv64-unknown-elf-gcc -O1 -mabi=lp64 -march=rv64i -o sum.o sum.c
riscv64-unknown-elf-gcc -Ofast -mabi=lp64 -march=rv64i -o sum.o sum.c
riscv64-unknown-elf-objdump -d sum.o
spike pk sum.o
spike -d pk sum.o
until pc 0 100b0
reg 0 sp
reg 0 a2
<enter> # run one cmd
reg 0 a0
<enter>
reg 0 sp
<enter>
reg 0 sp


cat <<EOF >load.S
.section .text
.global load
.type load, @function

load:
    add     a4, a0, zero // Initialize sum register a4 with 0x0
    add     a2, a0, a1   // Store count of 10 in a2, a1 is loaded iwth 0xa from main()
    add     a3, a0, zero // Initialize intermediate sum register a3 by 0x0
loop:
    add     a4, a3, a4   // Incremental addition
    addi    a3, a3, 1    // Increment intermediate register by 1
    blt     a3, a2, loop // If a3 < a2, branch to label named <loop>
    add     a0, a4, zero // Store final result to register a0, so that it can be read by main()
    ret
EOF

cat <<EOF > sums.c
#include <stdio.h>
extern int load(int x, int y);
int main() {
    int result = 0;
    int count = 9;
    result = load(0x0, count + 1);
    printf("Sum of number from 1 to %d is %d\n", count, result);
}
EOF

riscv64-unknown-elf-gcc -Ofast -mabi=lp64 -march=rv64i -o sums.o sums.c load.S


git clone https://github.com/kunalg123/riscv_workshop_collaterals.git
riscv_workshop_collaterals/lab/rv32im.sh # Run it