Arithmetic
Build values in registers
Instructions like addi, add, and sub are the
building blocks for counters, pointer updates, and intermediate results.
Guide ยท RISC-V assembly tutorial
RISC-V assembly tutorial for real programs
This RISC-V assembly tutorial focuses on the patterns you actually need to read and write: arithmetic, loops, memory access, branches, stack frames, and function calls. Every idea becomes easier when you can run it in StudyRISC-V and inspect the machine state after each instruction.
Core takeaway
Assembly gets easier when you read it as state transitions.
Each instruction changes a small part of the machine. Trace that change, and larger patterns like loops and function calls become manageable.
Foundation
How to read RISC-V assembly without getting lost
The simplest way to approach RISC-V assembly is to ask the same questions for every line. Which registers are being read? Which register or memory location is being written? Does the program counter move normally, or does control flow change? Once you ask those three questions consistently, a program stops looking like a wall of mnemonics and starts looking like a sequence of state updates.
In this RISC-V assembly tutorial, we will build from small patterns to larger ones. Start with arithmetic and immediates. Then learn memory access. Then move into branches and loops. Finally, connect everything through stack frames and function calls. That order mirrors how most real programs are composed.
Memory
Use loads and stores deliberately
lw, lh, lb, and their store variants show how data
moves between memory and registers in a load-store ISA.
Control flow
Trace branches and jumps carefully
Loops and conditions are just repeated PC updates. Branch instructions determine which block of code executes next.
Example
Arithmetic and loop counters
addi t0, x0, 0
addi t1, x0, 10
loop:
addi t0, t0, 1
blt t0, t1, loop
This is a compact example, but it teaches several useful patterns. t0 acts
as the loop counter, t1 stores the upper bound, and the branch checks whether
the loop should continue. If you run this in the StudyRISC-V
simulator, watch both registers and the program counter. The branch is not an abstract
condition anymore; it is a concrete decision about where execution continues.
Memory access
Arrays and pointers are easier when you inspect addresses.
A common stumbling block in RISC-V assembly is pointer math. Students know conceptually
that arrays are contiguous in memory, but they lose track of addresses once offsets show
up in code. The solution is to trace one address at a time. When you compute
base + index * 4, pause and verify the address. When you issue a
lw, check which word was read. When you issue a sw, inspect the
destination in memory. This is where an interactive simulator is dramatically more useful
than a printed code listing.
The same principle applies to strings, buffers, and stack-resident locals. Memory access becomes much clearer once every effective address is visible in context.
Function calls
Stack frames turn procedure calls into readable structure.
A RISC-V assembly tutorial would be incomplete without stack frames. When one function
calls another, the machine needs a place to preserve return addresses, saved registers, and
local storage. That is why prologues often adjust sp, save ra,
and optionally save s0 or other callee-saved registers.
The mental shift is important: a stack frame is not just bookkeeping. It is the layout that allows nested execution contexts to coexist safely. If you inspect the stack in the simulator while stepping through a function call, you can watch that frame form and later unwind. That makes calling convention much easier to internalize than reading a table in isolation.
Practice plan
Use examples, then reinforce them with problems.
After working through examples, apply the same patterns in RISC-V practice problems and checkpoint exercises. Problems force you to reconstruct a solution from the primitives you just learned, which is where real fluency begins. If you need more explanation, move back to the beginner guide or the full docs. If you need a quicker mnemonic refresher, use the instruction reference.
That loop between example, execution, and practice is what makes a RISC-V assembly tutorial useful instead of merely readable.
Run each assembly pattern where you can see registers, memory, and stack state update live.
Open StudyRISC-V, load a sample, and step through it line by line until the behavior feels obvious instead of symbolic.