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-rw-r--r--isaac.c110
1 files changed, 0 insertions, 110 deletions
diff --git a/isaac.c b/isaac.c
deleted file mode 100644
index 014c4d9..0000000
--- a/isaac.c
+++ /dev/null
@@ -1,110 +0,0 @@
-/*
-------------------------------------------------------------------------------
-isaac.c: By Bob Jenkins. My random number generator, ISAAC.
-MODIFIED:
- 960327: Creation (addition of randinit, really)
- 970719: use context, not global variables, for internal state
- 980324: make a portable version
- 991209: modified for inclusion with GNU Backgammon by Gary Wong
- 070121: modified for inclusion with flam3 by Erik Reckase
-------------------------------------------------------------------------------
-*/
-
-#include "isaacs.h"
-#include "isaac.h"
-
-#define ind(mm,x) ((mm)[(x>>2)&(RANDSIZ-1)])
-#define rngstep(mix,a,b,mm,m,m2,r,x) \
-{ \
- x = *m; \
- a = ((a^(mix)) + *(m2++)) & 0xffffffff; \
- *(m++) = y = (ind(mm,x) + a + b) & 0xffffffff; \
- *(r++) = b = (ind(mm,y>>RANDSIZL) + x) & 0xffffffff; \
-}
-
-void isaac(randctx *ctx)
-{
- register ub4 a,b,x,y,*m,*mm,*m2,*r,*mend;
- mm=ctx->randmem; r=ctx->randrsl;
- a = ctx->randa; b = (ctx->randb + (++ctx->randc)) & 0xffffffff;
- for (m = mm, mend = m2 = m+(RANDSIZ/2); m<mend; )
- {
- rngstep( a<<13, a, b, mm, m, m2, r, x);
- rngstep( a>>6 , a, b, mm, m, m2, r, x);
- rngstep( a<<2 , a, b, mm, m, m2, r, x);
- rngstep( a>>16, a, b, mm, m, m2, r, x);
- }
- for (m2 = mm; m2<mend; )
- {
- rngstep( a<<13, a, b, mm, m, m2, r, x);
- rngstep( a>>6 , a, b, mm, m, m2, r, x);
- rngstep( a<<2 , a, b, mm, m, m2, r, x);
- rngstep( a>>16, a, b, mm, m, m2, r, x);
- }
- ctx->randb = b; ctx->randa = a;
-}
-
-
-#define mix(a,b,c,d,e,f,g,h) \
-{ \
- a^=b<<11; d+=a; b+=c; \
- b^=c>>2; e+=b; c+=d; \
- c^=d<<8; f+=c; d+=e; \
- d^=e>>16; g+=d; e+=f; \
- e^=f<<10; h+=e; f+=g; \
- f^=g>>4; a+=f; g+=h; \
- g^=h<<8; b+=g; h+=a; \
- h^=a>>9; c+=h; a+=b; \
-}
-
-/* if (flag==TRUE), then use the contents of randrsl[] to initialize mm[]. */
-void irandinit(randctx *ctx, word flag)
-{
- word i;
- ub4 a,b,c,d,e,f,g,h;
- ub4 *m,*r;
- ctx->randa = ctx->randb = ctx->randc = 0;
- m=ctx->randmem;
- r=ctx->randrsl;
- a=b=c=d=e=f=g=h=0x9e3779b9; /* the golden ratio */
-
- for (i=0; i<4; ++i) /* scramble it */
- {
- mix(a,b,c,d,e,f,g,h);
- }
-
- if (flag)
- {
- /* initialize using the contents of r[] as the seed */
- for (i=0; i<RANDSIZ; i+=8)
- {
- a+=r[i ]; b+=r[i+1]; c+=r[i+2]; d+=r[i+3];
- e+=r[i+4]; f+=r[i+5]; g+=r[i+6]; h+=r[i+7];
- mix(a,b,c,d,e,f,g,h);
- m[i ]=a; m[i+1]=b; m[i+2]=c; m[i+3]=d;
- m[i+4]=e; m[i+5]=f; m[i+6]=g; m[i+7]=h;
- }
- /* do a second pass to make all of the seed affect all of m */
- for (i=0; i<RANDSIZ; i+=8)
- {
- a+=m[i ]; b+=m[i+1]; c+=m[i+2]; d+=m[i+3];
- e+=m[i+4]; f+=m[i+5]; g+=m[i+6]; h+=m[i+7];
- mix(a,b,c,d,e,f,g,h);
- m[i ]=a; m[i+1]=b; m[i+2]=c; m[i+3]=d;
- m[i+4]=e; m[i+5]=f; m[i+6]=g; m[i+7]=h;
- }
- }
- else
- {
- for (i=0; i<RANDSIZ; i+=8)
- {
- /* fill in mm[] with messy stuff */
- mix(a,b,c,d,e,f,g,h);
- m[i ]=a; m[i+1]=b; m[i+2]=c; m[i+3]=d;
- m[i+4]=e; m[i+5]=f; m[i+6]=g; m[i+7]=h;
- }
- }
-
- isaac(ctx); /* fill in the first set of results */
- ctx->randcnt=RANDSIZ; /* prepare to use the first set of results */
-}