Register Guide
RISC-V v10 / v10 Register: Vector data register
v10 is an RVV vector register; element count and layout are controlled by vl, vtype, VLEN, and LMUL.
ABI name: v10; physical register: v10.
Save rule: Caller.
Read it through its psABI role first, then inspect how each instruction reads or writes it.
Physical Name v10ABI Name v10Save Rule Caller
Role
Vector data register
Convention
Caller-saved
Remember This First
t* registers are caller-saved, so callees may overwrite them.
psABI Reference
ABI register
v10 is an RVV vector register; element count and layout are controlled by vl, vtype, VLEN, and LMUL.
Preserved across calls: Caller
RISC-V psABI integer register conventionWhen It Fits Best
- - Hold short-lived temporary computation results.
- - Use them for local computations that do not need to survive calls.
- - Use them as caller-managed scratch registers.
When Not To Use It This Way
- - Do not keep values in t* across a call unless you save them yourself first.
- - Do not expect callees to restore t* for you.
What Happens Around A Call
1
t* registers are caller-saved, so callees may overwrite them.
2
If the caller still needs a t* value after a call, it must save it in advance.
Protect Temporary Values Before A Call
Examples explain the rule, not a complete programaddi t0, a0, 1
# If t0 is needed after the call, save it to an ABI-valid location first
call foo
# restore t0 from that saved location after the call returns