Function code size: Difference between revisions

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</syntaxhighlight>
</syntaxhighlight>


For '''assembler''' routines, either do the same but make MyProcEnd '''assembler''' too (still not sure if it works, I use the method below... but it definitely doesn’t work when mixing Pascal and assembler procedures), or do the following (finer and more future-compatible way that sadly does not compile with Pascal routines... and would miss the prologue and epilogue if it did):
For assembler routines, either do the same but '''make MyProcEnd assembler too''' (still not sure if it works, I use the method below... but it definitely doesn’t work when mixing Pascal and '''assembler''' procedures). Or do the following (finer and more future-compatible way that sadly does not compile with Pascal routines... and would miss the epilogue if it did):


<syntaxhighlight lang="pascal">
<syntaxhighlight lang="pascal">
label MyAsmProcStart, MyAsmProcEnd;
label MyAsmProcEnd;


procedure MyAsmProc; assembler;
procedure MyAsmProc; assembler;
asm
asm
MyAsmProcStart:
   // ...
   ...
MyAsmProcEnd:
MyAsmProcEnd:
end;
end;


begin
begin
   writeln('MyAsmProc code size: ', pointer(@MyAsmProcEnd) - pointer(@MyAsmProcStart), ' b');
   writeln('MyAsmProc code size: ', pointer(@MyAsmProcEnd) - pointer(@MyAsmProc), ' b');
end.
end.
</syntaxhighlight>
</syntaxhighlight>

Revision as of 20:11, 6 September 2023

Advice from programmer Rika.

Pascal function binary size can be measured (to within the procedure entry alignment... usually 16 bytes) with:

procedure MyProc;
begin
  // ...
end;

// Must immediately follow MyProc in the source!
// Uses the implementation detail that the linker will lay them out in the same order.
procedure MyProcEnd; 
begin
end;

begin
  writeln('MyProc code size: ', pointer(@MyProcEnd) - pointer(@MyProc), ' b');
end.

For assembler routines, either do the same but make MyProcEnd assembler too (still not sure if it works, I use the method below... but it definitely doesn’t work when mixing Pascal and assembler procedures). Or do the following (finer and more future-compatible way that sadly does not compile with Pascal routines... and would miss the epilogue if it did):

label MyAsmProcEnd;

procedure MyAsmProc; assembler;
asm
  // ...
MyAsmProcEnd:
end;

begin
  writeln('MyAsmProc code size: ', pointer(@MyAsmProcEnd) - pointer(@MyAsmProc), ' b');
end.