Code demonstrating hand-crafted and compiler-generated function inlining

inlining.c

static int compute_triangle_number(int base) {
    int base_incremented = base + 1;
    int numerator = base * base_incremented;
    return numerator/2;
}

long simple_bonus_threshold(unsigned int number) {
    int triangle_number = compute_triangle_number(number);
    return 3 * triangle_number;
}

inlining_inlined_arm64.asm

// -finline-functions-called-once
// or
// -finline-small-functions
// or
// -finline-functions
// and/or
// mark compute_triangle_number as `inline`

simple_bonus_threshold:
        madd    w0, w0, w0, w0
        add     w0, w0, w0, lsr 31
        and     w1, w0, -2
        add     w0, w1, w0, asr 1
        sxtw    x0, w0
        ret

inlining_inlined_x86-64.asm

# -finline-functions-called-once
# or
# -finline-small-functions
# or
# -finline-functions
# and/or
# mark compute_triangle_number as `inline`

simple_bonus_threshold:
        leal    1(%rdi), %eax
        imull   %eax, %edi
        movl    %edi, %eax
        shrl    $31, %eax
        addl    %edi, %eax
        movl    %eax, %edx
        sarl    %edx
        andl    $-2, %eax
        addl    %edx, %eax
        cltq
        ret

inlining_not-inlined_arm64.asm

compute_triangle_number:
        madd    w0, w0, w0, w0
        add     w0, w0, w0, lsr 31
        asr     w0, w0, 1
        ret
simple_bonus_threshold:
        stp     x29, x30, [sp, -16]!
        mov     x29, sp
        bl      compute_triangle_number
        add     w0, w0, w0, lsl 1
        sxtw    x0, w0
        ldp     x29, x30, [sp], 16
        ret

inlining_not-inlined_x86-64.asm

compute_triangle_number:
        leal    1(%rdi), %eax
        imull   %eax, %edi
        movl    %edi, %eax
        shrl    $31, %eax
        addl    %edi, %eax
        sarl    %eax
        ret
simple_bonus_threshold:
        call    compute_triangle_number
        leal    (%rax,%rax,2), %eax
        cltq
        ret