From: krishna.myneni@ccreweb.org   
      
   On 7/14/24 07:20, Krishna Myneni wrote:   
   > On 7/14/24 04:02, albert@spenarnc.xs4all.nl wrote:   
   >> In article <2024Jul13.173138@mips.complang.tuwien.ac.at>,   
   >> Anton Ertl  wrote:   
   >>    
   >>>   
   >>> In any case, if you are a system implementor, you may want to check   
   >>> your DOES> implementation with a microbenchmark that stores into the   
   >>> does-defined word in a case where that word is not inlined.   
   >>   
   >> Is that equally valid for indirect threaded code?   
   >> In indirect threaded code the instruction and data cache   
   >> are more separated, e.g. in a simple Forth all the low level   
   >> code could fit in the I-cache, if I'm not mistaken.   
   >>   
   >   
   >   
   > Let's check. In kForth-64, an indirect threaded code system,   
   >   
   > .s   
   >    
   >   ok   
   > f.s   
   > fs:    
   >   ok   
   > ms@ b4 ms@ swap - .   
   > 4274  ok   
   > ms@ b5 ms@ swap - .   
   > 3648  ok   
   >   
   > So b5 appears to be more efficient that b4 ( the version with DOES> ).   
   >   
      
   This discrepancy between b4 and b5 is due to the fact that, in kForth,   
   DOES> not inline the code into the created word. So there is room for   
   improvement in the implementation of DOES> in kForth. There are other   
   important pressing issues to deal with, such as making the User's Manual   
   more useful (the most important item) and adding other standardized   
   words, but improving DOES> is low-hanging fruit.   
      
   --   
   Krishna   
      
      
   === begin code ===   
   // DOES>  ( -- )   
   //   
   // Forth 2012   
   int CPP_does()   
   {   
      // Allocate new opcode array   
      
      byte* p = new byte[2*WSIZE+4];   
      
      // Insert pfa of last word in dictionary   
      
      p[0] = OP_ADDR;   
      WordListEntry* pWord = *(pCompilationWL->end() - 1);   
      *((long int*)(p+1)) = (long int) pWord->Pfa;   
      
      // Insert current instruction ptr   
      
      p[WSIZE+1] = OP_ADDR;   
      *((long int*)(p+WSIZE+2)) = (long int)(GlobalIp + 1);   
      
      p[2*WSIZE+2] = OP_EXECUTE_BC;   
      p[2*WSIZE+3] = OP_RET;   
      
      pWord->Cfa = (void*) p;   
      pWord->WordCode = OP_DEFINITION;   
      
      L_ret();   
      return 0;   
   }   
   === end code ==   
      
   --- SoupGate-Win32 v1.05   
    * Origin: you cannot sedate... all the things you hate (1:229/2)