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using assembly and intrinsics in C code (Arm Compiler 6)

yukirose

dear arm,

Is there a more detailed document that introduces how to use assembly and intrinsics in C code?

I found a breif introduction in migration_and_compatibility_guide_v6.18. But after reading it, I still don't know how to modify the format to meet Arm Compiler 6' requirements .

The code blow shows the example in migration_and_compatibility_guide_v6.18: 

// __asm in Arm Compiler 5
int add(int i, int j)
{
    int res;
    __asm
    {
        ADD res, i, j
        SUB res, i, res
    }
    return res;
}

// __asm in Arm Compiler 6
int add(int i, int j)
{
    int res = 0;
    __asm
    (
        "ADD %[result], %[input_i], %[input_j] \t\n"
        "SUB %[result], %[input_i], %[result] \t\n"
        : [result] "=&r" (res)
        : [input_i] "r" (i), [input_j] "r" (j)
        );
    return res;
}

But how should I modify the code below to meet Arm Compiler 6's requirements?

MOV sum, var1, LSL #16
QADD sum, sum, temp
MOV result, sum, ASR #16
MOV zero, #0
RSB var2_inv, var2, #0

many thanks!

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