xref: /petsc/include/petscbt.h (revision f9426fe092dba0ba2fdf65dfec8d938c4b10a31c)
1 
2 #if !defined(__PETSCBT_H)
3 #define __PETSCBT_H
4 
5 #include <petscconf.h>
6 #include <petscviewer.h>
7 
8 /*S
9      PetscBT - PETSc bitarrays
10 
11      Level: advanced
12 
13      PetscBTCreate(m,&bt)         - creates a bit array with enough room to hold m values
14      PetscBTDestroy(&bt)          - destroys the bit array
15      PetscBTMemzero(m,bt)         - zeros the entire bit array (sets all values to false)
16      PetscBTSet(bt,index)         - sets a particular entry as true
17      PetscBTClear(bt,index)       - sets a particular entry as false
18      PetscBTLookup(bt,index)      - returns the value
19      PetscBTLookupSet(bt,index)   - returns the value and then sets it true
20      PetscBTLookupClear(bt,index) - returns the value and then sets it false
21      PetscBTLength(m)             - returns number of bytes in array with m bits
22      PetscBTView(m,bt,viewer)     - prints all the entries in a bit array
23 
24     We do not currently check error flags on PetscBTSet(), PetscBTClear(), PetscBTLookup(),
25     PetcBTLookupSet(), PetscBTLength() cause error checking would cost hundreds more cycles then
26     the operation.
27 
28 S*/
29 typedef char* PetscBT;
30 
31 
32 PETSC_STATIC_INLINE PetscInt  PetscBTLength(PetscInt m)
33 {
34   return  ((m)/PETSC_BITS_PER_BYTE+1);
35 }
36 
37 PETSC_STATIC_INLINE PetscErrorCode PetscBTMemzero(PetscInt m,PetscBT array)
38 {
39   return PetscMemzero(array,sizeof(char)*((m)/PETSC_BITS_PER_BYTE+1));
40 }
41 
42 PETSC_STATIC_INLINE PetscErrorCode PetscBTDestroy(PetscBT *array)
43 {
44   return PetscFree(*array);
45 }
46 
47 PETSC_STATIC_INLINE char PetscBTLookup(PetscBT array,PetscInt index)
48 {
49   char      BT_mask,BT_c;
50   PetscInt  BT_idx;
51 
52  return  (BT_idx        = (index)/PETSC_BITS_PER_BYTE,
53           BT_c          = array[BT_idx],
54           BT_mask       = (char)1 << ((index)%PETSC_BITS_PER_BYTE),
55           BT_c & BT_mask);
56 }
57 
58 PETSC_STATIC_INLINE PetscErrorCode PetscBTView(PetscInt m,const PetscBT bt,PetscViewer viewer)
59 {
60   PetscInt       i;
61   PetscErrorCode ierr;
62 
63   ierr = PetscViewerASCIIGetStdout(PETSC_COMM_SELF,&viewer);CHKERRQ(ierr);
64   ierr = PetscViewerASCIISynchronizedAllow(viewer,PETSC_TRUE);CHKERRQ(ierr);
65   for (i=0; i<m; i++) {
66     ierr = PetscViewerASCIISynchronizedPrintf(viewer,"%D %d\n",i,PetscBTLookup(bt,i));CHKERRQ(ierr);
67   }
68   ierr = PetscViewerFlush(viewer);CHKERRQ(ierr);
69   ierr = PetscViewerASCIISynchronizedAllow(viewer,PETSC_FALSE);CHKERRQ(ierr);
70   return 0;
71 }
72 
73 PETSC_STATIC_INLINE PetscErrorCode PetscBTCreate(PetscInt m,PetscBT *array)
74 {
75   return (PetscMalloc(((m)/PETSC_BITS_PER_BYTE+1)*sizeof(char),array) || PetscBTMemzero(m,*array));
76 }
77 
78 PETSC_STATIC_INLINE char PetscBTLookupSet(PetscBT array,PetscInt index)
79 {
80   char      BT_mask,BT_c;
81   PetscInt  BT_idx;
82 
83   return (BT_idx        = (index)/PETSC_BITS_PER_BYTE,
84           BT_c          = array[BT_idx],
85           BT_mask       = (char)1 << ((index)%PETSC_BITS_PER_BYTE),
86           array[BT_idx] = BT_c | BT_mask,
87           BT_c & BT_mask);
88 }
89 
90 PETSC_STATIC_INLINE PetscErrorCode PetscBTSet(PetscBT array,PetscInt index)
91 {
92   char      BT_mask,BT_c;
93   PetscInt  BT_idx;
94 
95   BT_idx        = (index)/PETSC_BITS_PER_BYTE;
96   BT_c          = array[BT_idx];
97   BT_mask       = (char)1 << ((index)%PETSC_BITS_PER_BYTE);
98   array[BT_idx] = BT_c | BT_mask;
99   return 0;
100 }
101 
102 PETSC_STATIC_INLINE char PetscBTLookupClear(PetscBT array,PetscInt index)
103 {
104   char      BT_mask,BT_c;
105   PetscInt  BT_idx;
106 
107   return (BT_idx        = (index)/PETSC_BITS_PER_BYTE,
108           BT_c          = array[BT_idx],
109           BT_mask       = (char)1 << ((index)%PETSC_BITS_PER_BYTE),
110           array[BT_idx] = BT_c & (~BT_mask),
111           BT_c & BT_mask);
112 }
113 
114 PETSC_STATIC_INLINE PetscErrorCode PetscBTClear(PetscBT array,PetscInt index)
115 {
116   char      BT_mask,BT_c;
117   PetscInt  BT_idx;
118 
119   BT_idx        = (index)/PETSC_BITS_PER_BYTE;
120   BT_c          = array[BT_idx];
121   BT_mask       = (char)1 << ((index)%PETSC_BITS_PER_BYTE);
122   array[BT_idx] = BT_c & (~BT_mask);
123  return 0;
124 }
125 
126 
127 #endif
128