#define SOMETHING1 STMT_START { assert( something ); if(some_complex_condition) wrapped_function1( aTHX_, ... ); assert(something_else ) } STMT_END
#define SOMETHING2 STMT_START { assert( something ); if(some_complex_condition) wrapped_function2( aTHX_, ... ); assert(something_else ) } STMT_END
#define SOMETHING3 STMT_START { assert( something ); if(some_complex_condition) wrapped_function3( aTHX_, ... ); assert(something_else ) } STMT_END

int someFunction( aTHX_  ... ) {
    dATHX;
    
    ...;
    SOMETHING1( ... );
    ...;
    SOMETHING2( ... );
    ...;
    SOMETHING3( ... );
    RETURN;
}

##</code><code>##

#include <windows.h>
#include <stdio.h>

char b[ 30 ] =  {0,};
char *commify( ULONG64 n ) {
	void *x = memset( b, 0, 30 );
	int c1 = sprintf( b, "%I64u", (ULONG64)n );
	int c2 = c1;
	int c = 0;

	while( ( c1 -= 3 ) > 0 ) {
		memmove( &b[ c1 + 1 ], &b[ c1 ], c2 - c1 + c );
		b[ c1 ] = ',';
		c++;
	}
	return b;
}

volatile int x;

void x1( int i ) {
	x = i;
	return;
}

void x2( int i ) {
	if( !( i & 1 ) )
	    return;
	x = i;
	return;
}


int main( int argc, char **argv ) {
	int n = atol( argv[1] );
	int i;
	ULONG64 start, end;
	HANDLE hThread = GetCurrentThread();

    QueryThreadCycleTime( hThread, &start );
    for( i = 0; i < n; ++i )
		if( i & 1 )
		    x1( i );
    QueryThreadCycleTime( hThread, &end );
	printf( "Inline condition: %15.15s\n", commify( end - start ) );

    QueryThreadCycleTime( hThread, &start );
	for( i = 0; i < n; ++i )
		x2( i );
    QueryThreadCycleTime( hThread, &end );
	printf( "Inbody condition: %15.15s\n", commify( end - start ) );

	return 0;
}

##</code><code>##

C:\test>cl /Ox calloverhead.c
Microsoft (R) C/C++ Optimizing Compiler Version 15.00.21022.08 for x64
Copyright (C) Microsoft Corporation.  All rights reserved.

calloverhead.c
Microsoft (R) Incremental Linker Version 9.00.21022.08
Copyright (C) Microsoft Corporation.  All rights reserved.

/out:calloverhead.exe
calloverhead.obj

C:\test>calloverhead 10000000
Inline condition:      60,068,106
Inbody condition:      45,064,458

C:\test>calloverhead 10000000
Inline condition:      60,037,515
Inbody condition:      45,084,879

C:\test>calloverhead 10000000
Inline condition:      60,048,828
Inbody condition:      45,057,681

C:\test>calloverhead 10000000
Inline condition:      60,032,691
Inbody condition:      45,032,724