What is Calling convention?

Calling convention in the explanations

• A calling convention specifies which registers hold arguments, where return values go, which registers the callee may clobber and how the stack is used.

  What is the main purpose of defining a calling convention?

• In the standard RISC-V calling convention, up to eight integer arguments are passed in a0-a7 (x10-x17), and the return value comes back in a0, or in a0 and a1 for values such as 64-bit integers on RV32.

  In the standard RISC-V calling convention, which registers …

• They also have aliases such as ra, sp and a0, whose roles are set by the calling convention.

  Which describes the general-purpose integer registers of RI…

Questions that mention Calling convention (9)

1. What is the main purpose of defining a calling convention?
2. In the standard RISC-V calling convention, which registers pass integer arguments and return values?
3. In the standard RISC-V calling convention, when calling a function with ten integer arguments, where are the ninth and tenth passed?
4. In the RISC-V calling convention, s0-s11 are callee-saved registers. What does that mean?
5. In the RISC-V calling convention, t0-t6 are caller-saved. If a function wants to keep using a value in t0 after calling another function, what should it do?
6. The standard RISC-V calling convention requires sp to be a multiple of 16 bytes on function entry. What is the main reason?
7. Which describes the general-purpose integer registers of RISC-V RV32I (the 32-bit base integer instruction set)?
8. What does the RISC-V instruction "jal ra, func" do?
9. Which correctly describes an ABI (application binary interface)?

Related terms

Application binary interface (ABI) Stack pointer Return address Pseudo-instruction Instruction set architecture (ISA) Addressing mode Assembler Branch delay slot Callee-saved register Caller-saved register