Integer Multiply/Divide on Sparc

[Teemu Torma]

In article <1313 at kuling.UUCP> irf at kuling.UUCP (Bo Thide') writes:

   ================================================================================
			 register      auto      auto       int  function      auto
			      int     short      long  multiply  call+ret    double
    HP9000/370 (fpa -O)     0.22      0.26      0.22      1.35      3.96      0.62
	  HP9000/370 (-O)   0.21      0.26      0.22      1.35      3.08      1.21
    HP9000/370 (fpa no -O)  0.26      0.40      0.36      1.44      4.42      1.56
       HP9000/370 (no -O)   0.26      0.40      0.37      1.45      3.38      2.72
	  HP9000/835 (-O)   0.27      0.29      0.27      5.49      0.31      0.27 
       HP9000/835 (no -O)   0.29      0.53      0.45      5.62      0.31      0.59
	     Sun SS1 (-O)   0.29      0.33      0.30     19.5       0.49      0.59
	  Sun SS1 (no -O)   0.38      0.40      0.35     19.7       0.51      0.72
   ================================================================================
   There is no question that Sun SparcStation 1 is *extremely* slow on integer
   multiply even for a RISC architecture -- scaling the HP-PA results to the
   same clock speed as the SPARC (20 MHz) we see that HP-PA is about 470% faster
   than SPARC!!  Our results also show that integer arithmetics on CISC (MC68030)
   is much faster than on RISC (HP-PA, SPARC).

Strange. I got much better int multiply results from Sun SS1. Gcc
version was 1.36.

			 register      auto      auto       int  function      auto
			      int     short      long  multiply  call+ret    double
Sun 4/60 (cc, no -O)	  0.38      0.40      0.36      3.52      0.28      0.72    
Sun 4/60 (cc, -O)	  0.32      0.35      0.32      3.62      0.28      0.62    
Sun 4/60 (cc, -O2)	  0.30      0.33      0.30      3.32      0.26      0.61    
Sun 4/60 (cc, -O3)	  0.30      0.33      0.30      3.45      0.28      0.63    
Sun 4/60 (gcc, no -O)	  0.21      0.38      0.38      3.50      0.27      0.77    
Sun 4/60 (gcc, -O)	  0.18      0.21      0.18      3.57      0.27      0.42    
Sun 4/60 (gcc, <2>)	  0.17      0.22      0.19      3.67      0.28      0.42    
Sun 4/60 (gcc, <3>)	  0.17      0.21      0.18      3.52      0.27      0.40    

gcc <2>: -fstrength-reduce -fcombine-regs -fomit-frame-pointer
gcc <3>: as <2> including -mno-epologue
--
Teemu Torma
Front End Oy, Helsinki, Finland
Internet: tot at nyse.frend.fi