objective c - "return" and stepping through a function in Xcode -

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i've got nested if statements perform data check. if result i'm looking for, store data in array , call return; in order break out of function.

when stepping through in debugger, have noticed rather breaking out of function immediately, 1 return call instead moves application different return call, , then breaks out of function. question twofold:

1) why happen?
2) should worry about? hasn't caused me problems far.

here's exact code below. happens 100% of time when final return in code (look near end) reached. have put comment in code return function goes after last one.

if ([self comparepx:[self getavgpxclrforrow:rowedge andcol:coledge fordirection:0] tobins:bgbins] == nil) {              coledge--;             while (coledge >= includedareaorigincol) {                 if ([self comparepx:[self getavgpxclrforrow:rowedge andcol:coledge fordirection:0] tobins:bgbins] != nil) {                     coledge++;                     prevedgept = cgpointmake(coledge, rowedge);                     [edgeptsleft addobject:[nsvalue valuewithcgpoint:prevedgept]];                      //first return steps return                     return;                 } else {                     if ([self comparepx:[self getavgpxclrforrow:rowedge-1 andcol:coledge fordirection:0] tobins:bgbins] != nil) {                         prevedgept = cgpointmake(coledge, rowedge);                         [edgeptsleft addobject:[nsvalue valuewithcgpoint:prevedgept]];                         return;                     } else {                         if (rowedge - prevedgept.y == 0) return;                          isfindingleftedge = no;                          //first return                         return;                     }                 }             }          }

that's result of compiler optimization.

there's bit of code needs run on function before going caller (possibly doing cleanups or stack manipulations, possibly de-allocations).
compiler have selected not repeat code, both "return" statements end running same assembly block, , debugger doesn't have enough information understand that.

nothing worry about.


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