On Fri, Mar 10, 2017 at 02:23:26PM +0000, Dibyendu Majumdar wrote:
> Hi,
>
> This example fails:
>
> extern int (*f) (int);
> int main(int argc, const char *argv[]) {
> if (f) {
> return (*f)(6);
> }
> }
>
> The linearized output is:
>
> main:
> .L0:
> <entry-point>
> load.64 %r1(f) <- 0[f]
> br %r1(f), .L1, .L3
> .L1:
> load %r3 <- 0[%r1(f)]
> call.32 %r4 <- %r3, $6
> br .L3
> .L3:
> ret.32 %r4
>
> It is the second load that is failing. Am investigating the cause - it
> seems something to do with calc_memop_addr().
No, it's a problem with the linearized code.
There is no reasons for this second load to even exist.
You can see this by replacing '(*f)(6)' by the equivalent 'f(6)'.
Also you should be careful with this example as there is no
return for the 'else' part which create some undefined value
which can create weirdness.
-- Luc Van Oostenryck
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