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authorDenys Vlasenko <vda.linux@googlemail.com>2023-04-23 13:42:19 +0200
committerDenys Vlasenko <vda.linux@googlemail.com>2023-04-23 14:02:20 +0200
commit382e1634972f7aab883259dd22cf721d1c205055 (patch)
treec1d8a19cfa055df68f30fe3faa7018d48e1a43a8
parent7ddd233c807f71fc5a303e89ce166bc1cbccf89e (diff)
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factor: we can pack 21, not 20, 3-bit elements into packed wheel words
function old new delta packed_wheel 192 184 -8 factor_main 171 163 -8 ------------------------------------------------------------------------------ (add/remove: 0/0 grow/shrink: 0/2 up/down: 0/-16) Total: -16 bytes Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
Diffstat
-rw-r--r--coreutils/factor.c71
1 files changed, 35 insertions, 36 deletions
diff --git a/coreutils/factor.c b/coreutils/factor.c
index de8ea4e11..46dd2a0d7 100644
--- a/coreutils/factor.c
+++ b/coreutils/factor.c
@@ -48,38 +48,40 @@ typedef unsigned long half_t;
48 * Larger wheels improve sieving only slightly, but quickly grow in size 48 * Larger wheels improve sieving only slightly, but quickly grow in size
49 * (adding just one prime, 13, results in 5766 element sieve). 49 * (adding just one prime, 13, results in 5766 element sieve).
50 */ 50 */
51#define R(a,b,c,d,e,f,g,h,i,j,A,B,C,D,E,F,G,H,I,J) \ 51#define R(a,b,c,d,e,f,g,h,i,j,A,B,C,D,E,F,G,H,I,J,x) \
52 (((uint64_t)(a<<0) | (b<<3) | (c<<6) | (d<<9) | (e<<12) | (f<<15) | (g<<18) | (h<<21) | (i<<24) | (j<<27)) << 1) | \ 52 (((uint64_t)(a<<0) | (b<<3) | (c<<6) | (d<<9) | (e<<12) | (f<<15) | (g<<18) | (h<<21) | (i<<24) | (j<<27)) << 1) | \
53 (((uint64_t)(A<<0) | (B<<3) | (C<<6) | (D<<9) | (E<<12) | (F<<15) | (G<<18) | (H<<21) | (I<<24) | (J<<27)) << 31) 53 (((uint64_t)(A<<0) | (B<<3) | (C<<6) | (D<<9) | (E<<12) | (F<<15) | (G<<18) | (H<<21) | (I<<24) | (J<<27)) << 31) | \
54#define P(a,b,c,d,e,f,g,h,i,j,A,B,C,D,E,F,G,H,I,J) \ 54 ((uint64_t)x << 61)
55#define P(a,b,c,d,e,f,g,h,i,j,A,B,C,D,E,F,G,H,I,J,x) \
55 R( (a/2),(b/2),(c/2),(d/2),(e/2),(f/2),(g/2),(h/2),(i/2),(j/2), \ 56 R( (a/2),(b/2),(c/2),(d/2),(e/2),(f/2),(g/2),(h/2),(i/2),(j/2), \
56 (A/2),(B/2),(C/2),(D/2),(E/2),(F/2),(G/2),(H/2),(I/2),(J/2) ) 57 (A/2),(B/2),(C/2),(D/2),(E/2),(F/2),(G/2),(H/2),(I/2),(J/2), \
58 (x/2) \
59 )
57static const uint64_t packed_wheel[] = { 60static const uint64_t packed_wheel[] = {
58 /*1, 2, 2, 4, 2,*/ 61 /* 1, 2, */
59 P( 4, 2, 4, 6, 2, 6, 4, 2, 4, 6, 6, 2, 6, 4, 2, 6, 4, 6, 8, 4), //01 62 P( 2, 4, 2, 4, 2, 4, 6, 2, 6, 4, 2, 4, 6, 6, 2, 6, 4, 2, 6, 4, 6),
60 P( 2, 4, 2, 4,14, 4, 6, 2,10, 2, 6, 6, 4, 2, 4, 6, 2,10, 2, 4), //02 63 P( 8, 4, 2, 4, 2, 4,14, 4, 6, 2,10, 2, 6, 6, 4, 2, 4, 6, 2,10, 2),
61 P( 2,12,10, 2, 4, 2, 4, 6, 2, 6, 4, 6, 6, 6, 2, 6, 4, 2, 6, 4), //03 64 P( 4, 2,12,10, 2, 4, 2, 4, 6, 2, 6, 4, 6, 6, 6, 2, 6, 4, 2, 6, 4),
62 P( 6, 8, 4, 2, 4, 6, 8, 6,10, 2, 4, 6, 2, 6, 6, 4, 2, 4, 6, 2), //04 65 P( 6, 8, 4, 2, 4, 6, 8, 6,10, 2, 4, 6, 2, 6, 6, 4, 2, 4, 6, 2, 6),
63 P( 6, 4, 2, 6,10, 2,10, 2, 4, 2, 4, 6, 8, 4, 2, 4,12, 2, 6, 4), //05 66 P( 4, 2, 6,10, 2,10, 2, 4, 2, 4, 6, 8, 4, 2, 4,12, 2, 6, 4, 2, 6),
64 P( 2, 6, 4, 6,12, 2, 4, 2, 4, 8, 6, 4, 6, 2, 4, 6, 2, 6,10, 2), //06 67 P( 4, 6,12, 2, 4, 2, 4, 8, 6, 4, 6, 2, 4, 6, 2, 6,10, 2, 4, 6, 2),
65 P( 4, 6, 2, 6, 4, 2, 4, 2,10, 2,10, 2, 4, 6, 6, 2, 6, 6, 4, 6), //07 68 P( 6, 4, 2, 4, 2,10, 2,10, 2, 4, 6, 6, 2, 6, 6, 4, 6, 6, 2, 6, 4),
66 P( 6, 2, 6, 4, 2, 6, 4, 6, 8, 4, 2, 6, 4, 8, 6, 4, 6, 2, 4, 6), //08 69 P( 2, 6, 4, 6, 8, 4, 2, 6, 4, 8, 6, 4, 6, 2, 4, 6, 8, 6, 4, 2,10),
67 P( 8, 6, 4, 2,10, 2, 6, 4, 2, 4, 2,10, 2,10, 2, 4, 2, 4, 8, 6), //09 70 P( 2, 6, 4, 2, 4, 2,10, 2,10, 2, 4, 2, 4, 8, 6, 4, 2, 4, 6, 6, 2),
68 P( 4, 2, 4, 6, 6, 2, 6, 4, 8, 4, 6, 8, 4, 2, 4, 2, 4, 8, 6, 4), //10 71 P( 6, 4, 8, 4, 6, 8, 4, 2, 4, 2, 4, 8, 6, 4, 6, 6, 6, 2, 6, 6, 4),
69 P( 6, 6, 6, 2, 6, 6, 4, 2, 4, 6, 2, 6, 4, 2, 4, 2,10, 2,10, 2), //11 72 P( 2, 4, 6, 2, 6, 4, 2, 4, 2,10, 2,10, 2, 6, 4, 6, 2, 6, 4, 2, 4),
70 P( 6, 4, 6, 2, 6, 4, 2, 4, 6, 6, 8, 4, 2, 6,10, 8, 4, 2, 4, 2), //12 73 P( 6, 6, 8, 4, 2, 6,10, 8, 4, 2, 4, 2, 4, 8,10, 6, 2, 4, 8, 6, 6),
71 P( 4, 8,10, 6, 2, 4, 8, 6, 6, 4, 2, 4, 6, 2, 6, 4, 6, 2,10, 2), //13 74 P( 4, 2, 4, 6, 2, 6, 4, 6, 2,10, 2,10, 2, 4, 2, 4, 6, 2, 6, 4, 2),
72 P(10, 2, 4, 2, 4, 6, 2, 6, 4, 2, 4, 6, 6, 2, 6, 6, 6, 4, 6, 8), //14 75 P( 4, 6, 6, 2, 6, 6, 6, 4, 6, 8, 4, 2, 4, 2, 4, 8, 6, 4, 8, 4, 6),
73 P( 4, 2, 4, 2, 4, 8, 6, 4, 8, 4, 6, 2, 6, 6, 4, 2, 4, 6, 8, 4), //15 76 P( 2, 6, 6, 4, 2, 4, 6, 8, 4, 2, 4, 2,10, 2,10, 2, 4, 2, 4, 6, 2),
74 P( 2, 4, 2,10, 2,10, 2, 4, 2, 4, 6, 2,10, 2, 4, 6, 8, 6, 4, 2), //16 77 P(10, 2, 4, 6, 8, 6, 4, 2, 6, 4, 6, 8, 4, 6, 2, 4, 8, 6, 4, 6, 2),
75 P( 6, 4, 6, 8, 4, 6, 2, 4, 8, 6, 4, 6, 2, 4, 6, 2, 6, 6, 4, 6), //17 78 P( 4, 6, 2, 6, 6, 4, 6, 6, 2, 6, 6, 4, 2,10, 2,10, 2, 4, 2, 4, 6),
76 P( 6, 2, 6, 6, 4, 2,10, 2,10, 2, 4, 2, 4, 6, 2, 6, 4, 2,10, 6), //18 79 P( 2, 6, 4, 2,10, 6, 2, 6, 4, 2, 6, 4, 6, 8, 4, 2, 4, 2,12, 6, 4),
77 P( 2, 6, 4, 2, 6, 4, 6, 8, 4, 2, 4, 2,12, 6, 4, 6, 2, 4, 6, 2), //19 80 P( 6, 2, 4, 6, 2,12, 4, 2, 4, 8, 6, 4, 2, 4, 2,10, 2,10, 6, 2, 4),
78 P(12, 4, 2, 4, 8, 6, 4, 2, 4, 2,10, 2,10, 6, 2, 4, 6, 2, 6, 4), //20 81 P( 6, 2, 6, 4, 2, 4, 6, 6, 2, 6, 4, 2,10, 6, 8, 6, 4, 2, 4, 8, 6),
79 P( 2, 4, 6, 6, 2, 6, 4, 2,10, 6, 8, 6, 4, 2, 4, 8, 6, 4, 6, 2), //21 82 P( 4, 6, 2, 4, 6, 2, 6, 6, 6, 4, 6, 2, 6, 4, 2, 4, 2,10,12, 2, 4),
80 P( 4, 6, 2, 6, 6, 6, 4, 6, 2, 6, 4, 2, 4, 2,10,12, 2, 4, 2,10), //22 83 P( 2,10, 2, 6, 4, 2, 4, 6, 6, 2,10, 2, 6, 4,14, 4, 2, 4, 2, 4, 8),
81 P( 2, 6, 4, 2, 4, 6, 6, 2,10, 2, 6, 4,14, 4, 2, 4, 2, 4, 8, 6), //23 84 P( 6, 4, 6, 2, 4, 6, 2, 6, 6, 4, 2, 4, 6, 2, 6, 4, 2, 4,12, 2,12),
82 P( 4, 6, 2, 4, 6, 2, 6, 6, 4, 2, 4, 6, 2, 6, 4, 2, 4,12, 2,12), //24
83}; 85};
84#undef P 86#undef P
85#undef R 87#undef R
@@ -93,8 +95,8 @@ static const uint64_t packed_wheel[] = {
93 * function old new delta 95 * function old new delta
94 * wheel_tab - 485 +485 96 * wheel_tab - 485 +485
95 * 3-bit-packed insanity: 97 * 3-bit-packed insanity:
96 * packed_wheel - 192 +192 98 * packed_wheel - 184 +184
97 * factor_main 108 171 +63 99 * factor_main 108 163 +55
98 */ 100 */
99static void unpack_wheel(void) 101static void unpack_wheel(void)
100{ 102{
@@ -104,10 +106,7 @@ static void unpack_wheel(void)
104 setup_common_bufsiz(); 106 setup_common_bufsiz();
105 wheel_tab[0] = 1; 107 wheel_tab[0] = 1;
106 wheel_tab[1] = 2; 108 wheel_tab[1] = 2;
107 wheel_tab[2] = 2; 109 p = &wheel_tab[2];
108 wheel_tab[3] = 4;
109 wheel_tab[4] = 2;
110 p = &wheel_tab[5];
111 for (i = 0; i < ARRAY_SIZE(packed_wheel); i++) { 110 for (i = 0; i < ARRAY_SIZE(packed_wheel); i++) {
112 uint64_t v = packed_wheel[i]; 111 uint64_t v = packed_wheel[i];
113 while ((v & 0xe) != 0) { 112 while ((v & 0xe) != 0) {
generated by cgit v1.2.3-55-g6feb (git 2.39.1) at 2025-03-22 07:38:39 +0000