3 ms·

I've tested this under LispWorks, and it's pretty fast, although you I had to add this: (defun mandelbrot (x y) (declare (optimize (speed 3) (safety 0) (spac

by malkia 19y ago

I've tested this under LispWorks, and it's pretty fast, although you I had to add this: (defun mandelbrot (x y) (declare (optimize (speed 3) (safety 0) (space 0) (compilation-speed 0) (float 0))) Also the benchmark is flawed somehow, as some of the examples are using double, other float. Also the lisp (SBCL) example the printing of the stream was also in the equation. You should compute the result in array, then print it.

malkia 19y ago
I found more "bugs" in the LISP version: +BAILOUT+ constant needs to be 16.0, not 16, as it's used in floating-point comparison: (defconstant +BAILOUT+ 16.0) The "i" variable was declared fixnum in the incorrect place, it should be right after the "do" block: (do ((i 0 (incf i))) (nil) (declare (type fixnum i)) Also I've commented the printing, printing is slow, especially doing format for each character: (declaim (optimize (speed 3))) (defconstant +BAILOUT+ 16.0) (defconstant +MAX-ITERATIONS+ 1000) (defun mandelbrot (x y) (declare (optimize (speed 3) (safety 0) (space 0) (compilation-speed 0) #+lispworks (float 0))) (declare (type single-float x y)) (let ((cr (- y 0.5)) (ci x) (zi 0.0) (zr 0.0)) (declare (type single-float cr ci zi zr)) (do ((i 0 (incf i))) (nil) (declare (type fixnum i)) (let ((temp (the single-float ( zr zi))) (zr2 (the single-float ( zr zr))) (zi2 (the single-float ( zi zi)))) (declare (type single-float temp zr2 zi2)) (setq zr (the single-float (+ (- zr2 zi2) cr))) (setq zi (the single-float (+ temp temp ci))) (when ( (the single-float (+ zi2 zr2)) +BAILOUT+) (return-from mandelbrot i)) (when ( i +MAX-ITERATIONS+) (return-from mandelbrot 0))))))
malkia 19y ago
malkia 19y ago
Here is the disassembled version (LispWorks 5.02) CL-USER 14 (disassemble 'mandelbrot) 200B2732: 0: 55 push ebp 1: 89E5 move ebp, esp 3: 83EC20 sub esp, 20 6: C7042486200000 move [esp], 2086 13: 8B7D08 move edi, [ebp+8] 16: D94701 flds [edi+1] 19: D95DE8 fstps [ebp-18] 22: D94001 flds [eax+1] 25: D9053C7B0820 flds [20087B3C] ; 0.5 31: DEE9 fsubp st(1), st 33: D95DE4 fstps [ebp-1C] 36: D905447B0820 flds [20087B44] ; 0.0 42: D95DFC fstps [ebp-4] 45: D905447B0820 flds [20087B44] ; 0.0 51: D95DF8 fstps [ebp-8] 54: 33FF xor edi, edi L1: 56: D945F8 flds [ebp-8] 59: D95DF4 fstps [ebp-C] 62: D945FC flds [ebp-4] 65: D84DF4 fmuls [ebp-C] 68: D95DF4 fstps [ebp-C] 71: D945F8 flds [ebp-8] 74: D95DF0 fstps [ebp-10] 77: D945F8 flds [ebp-8] 80: D84DF0 fmuls [ebp-10] 83: D95DF0 fstps [ebp-10] 86: D945FC flds [ebp-4] 89: D95DEC fstps [ebp-14] 92: D945FC flds [ebp-4] 95: D84DEC fmuls [ebp-14] 98: D955EC fsts [ebp-14] 101: D86DF0 fsubrs [ebp-10] 104: D845E4 fadds [ebp-1C] 107: D95DF8 fstps [ebp-8] 110: D945F4 flds [ebp-C] 113: D845F4 fadds [ebp-C] 116: D845E8 fadds [ebp-18] 119: D95DFC fstps [ebp-4] 122: D945EC flds [ebp-14] 125: D845F0 fadds [ebp-10] 128: D905347A0820 flds [20087A34] ; 16.0 134: DED9 fcompp 136: DFE0 fnstsw ax 138: 9E sahf 139: 7A09 jp L3 141: 7307 jnb L3 143: 89F8 move eax, edi 145: FD std L2: 146: C9 leave 147: C20400 ret 4 L3: 150: 81FFA00F0000 cmp edi, FA0 156: 7E05 jle L4 158: 33C0 xor eax, eax 160: FD std 161: EBEF jmp L2 L4: 163: 83C704 add edi, 4 166: EB90 jmp L1 168: 90 nop 169: 90 nop NIL

by malkia 19y ago

malkia 19y ago

I found more "bugs" in the LISP version: +BAILOUT+ constant needs to be 16.0, not 16, as it's used in floating-point comparison: (defconstant +BAILOUT+ 16.0) The "i" variable was declared fixnum in the incorrect place, it should be right after the "do" block: (do ((i 0 (incf i))) (nil) (declare (type fixnum i)) Also I've commented the printing, printing is slow, especially doing format for each character: (declaim (optimize (speed 3))) (defconstant +BAILOUT+ 16.0) (defconstant +MAX-ITERATIONS+ 1000) (defun mandelbrot (x y) (declare (optimize (speed 3) (safety 0) (space 0) (compilation-speed 0) #+lispworks (float 0))) (declare (type single-float x y)) (let ((cr (- y 0.5)) (ci x) (zi 0.0) (zr 0.0)) (declare (type single-float cr ci zi zr)) (do ((i 0 (incf i))) (nil) (declare (type fixnum i)) (let ((temp (the single-float ( zr zi))) (zr2 (the single-float ( zr zr))) (zi2 (the single-float ( zi zi)))) (declare (type single-float temp zr2 zi2)) (setq zr (the single-float (+ (- zr2 zi2) cr))) (setq zi (the single-float (+ temp temp ci))) (when ( (the single-float (+ zi2 zr2)) +BAILOUT+) (return-from mandelbrot i)) (when ( i +MAX-ITERATIONS+) (return-from mandelbrot 0))))))

malkia 19y ago

Here is the disassembled version (LispWorks 5.02) CL-USER 14 (disassemble 'mandelbrot) 200B2732: 0: 55 push ebp 1: 89E5 move ebp, esp 3: 83EC20 sub esp, 20 6: C7042486200000 move [esp], 2086 13: 8B7D08 move edi, [ebp+8] 16: D94701 flds [edi+1] 19: D95DE8 fstps [ebp-18] 22: D94001 flds [eax+1] 25: D9053C7B0820 flds [20087B3C] ; 0.5 31: DEE9 fsubp st(1), st 33: D95DE4 fstps [ebp-1C] 36: D905447B0820 flds [20087B44] ; 0.0 42: D95DFC fstps [ebp-4] 45: D905447B0820 flds [20087B44] ; 0.0 51: D95DF8 fstps [ebp-8] 54: 33FF xor edi, edi L1: 56: D945F8 flds [ebp-8] 59: D95DF4 fstps [ebp-C] 62: D945FC flds [ebp-4] 65: D84DF4 fmuls [ebp-C] 68: D95DF4 fstps [ebp-C] 71: D945F8 flds [ebp-8] 74: D95DF0 fstps [ebp-10] 77: D945F8 flds [ebp-8] 80: D84DF0 fmuls [ebp-10] 83: D95DF0 fstps [ebp-10] 86: D945FC flds [ebp-4] 89: D95DEC fstps [ebp-14] 92: D945FC flds [ebp-4] 95: D84DEC fmuls [ebp-14] 98: D955EC fsts [ebp-14] 101: D86DF0 fsubrs [ebp-10] 104: D845E4 fadds [ebp-1C] 107: D95DF8 fstps [ebp-8] 110: D945F4 flds [ebp-C] 113: D845F4 fadds [ebp-C] 116: D845E8 fadds [ebp-18] 119: D95DFC fstps [ebp-4] 122: D945EC flds [ebp-14] 125: D845F0 fadds [ebp-10] 128: D905347A0820 flds [20087A34] ; 16.0 134: DED9 fcompp 136: DFE0 fnstsw ax 138: 9E sahf 139: 7A09 jp L3 141: 7307 jnb L3 143: 89F8 move eax, edi 145: FD std L2: 146: C9 leave 147: C20400 ret 4 L3: 150: 81FFA00F0000 cmp edi, FA0 156: 7E05 jle L4 158: 33C0 xor eax, eax 160: FD std 161: EBEF jmp L2 L4: 163: 83C704 add edi, 4 166: EB90 jmp L1 168: 90 nop 169: 90 nop NIL