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authorIngo Molnar <mingo@elte.hu>2008-01-30 07:30:11 -0500
committerIngo Molnar <mingo@elte.hu>2008-01-30 07:30:11 -0500
commit3d0d14f983b55a570b976976284df4c434af3223 (patch)
tree864f11c0ce5ee1e15acdd196018b79d0d0e2685d /arch/x86/math-emu/poly_atan.c
parenta4ec1effce83796209a0258602b0cf50026d86f2 (diff)
x86: lindent arch/i386/math-emu
lindent these files: errors lines of code errors/KLOC arch/x86/math-emu/ 2236 9424 237.2 arch/x86/math-emu/ 128 8706 14.7 no other changes. No code changed: text data bss dec hex filename 5589802 612739 3833856 10036397 9924ad vmlinux.before 5589802 612739 3833856 10036397 9924ad vmlinux.after the intent of this patch is to ease the automated tracking of kernel code quality - it's just much easier for us to maintain it if every file in arch/x86 is supposed to be clean. NOTE: it is a known problem of lindent that it causes some style damage of its own, but it's a safe tool (well, except for the gcc array range initializers extension), so we did the bulk of the changes via lindent, and did the manual fixups in a followup patch. the resulting math-emu code has been tested by Thomas Gleixner on a real 386 DX CPU as well, and it works fine. Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Diffstat (limited to 'arch/x86/math-emu/poly_atan.c')
-rw-r--r--arch/x86/math-emu/poly_atan.c353
1 files changed, 166 insertions, 187 deletions
diff --git a/arch/x86/math-emu/poly_atan.c b/arch/x86/math-emu/poly_atan.c
index 82f702952f69..2f4ac8143fc3 100644
--- a/arch/x86/math-emu/poly_atan.c
+++ b/arch/x86/math-emu/poly_atan.c
@@ -18,28 +18,25 @@
18#include "control_w.h" 18#include "control_w.h"
19#include "poly.h" 19#include "poly.h"
20 20
21
22#define HIPOWERon 6 /* odd poly, negative terms */ 21#define HIPOWERon 6 /* odd poly, negative terms */
23static const unsigned long long oddnegterms[HIPOWERon] = 22static const unsigned long long oddnegterms[HIPOWERon] = {
24{ 23 0x0000000000000000LL, /* Dummy (not for - 1.0) */
25 0x0000000000000000LL, /* Dummy (not for - 1.0) */ 24 0x015328437f756467LL,
26 0x015328437f756467LL, 25 0x0005dda27b73dec6LL,
27 0x0005dda27b73dec6LL, 26 0x0000226bf2bfb91aLL,
28 0x0000226bf2bfb91aLL, 27 0x000000ccc439c5f7LL,
29 0x000000ccc439c5f7LL, 28 0x0000000355438407LL
30 0x0000000355438407LL 29};
31} ;
32 30
33#define HIPOWERop 6 /* odd poly, positive terms */ 31#define HIPOWERop 6 /* odd poly, positive terms */
34static const unsigned long long oddplterms[HIPOWERop] = 32static const unsigned long long oddplterms[HIPOWERop] = {
35{
36/* 0xaaaaaaaaaaaaaaabLL, transferred to fixedpterm[] */ 33/* 0xaaaaaaaaaaaaaaabLL, transferred to fixedpterm[] */
37 0x0db55a71875c9ac2LL, 34 0x0db55a71875c9ac2LL,
38 0x0029fce2d67880b0LL, 35 0x0029fce2d67880b0LL,
39 0x0000dfd3908b4596LL, 36 0x0000dfd3908b4596LL,
40 0x00000550fd61dab4LL, 37 0x00000550fd61dab4LL,
41 0x0000001c9422b3f9LL, 38 0x0000001c9422b3f9LL,
42 0x000000003e3301e1LL 39 0x000000003e3301e1LL
43}; 40};
44 41
45static const unsigned long long denomterm = 0xebd9b842c5c53a0eLL; 42static const unsigned long long denomterm = 0xebd9b842c5c53a0eLL;
@@ -48,182 +45,164 @@ static const Xsig fixedpterm = MK_XSIG(0xaaaaaaaa, 0xaaaaaaaa, 0xaaaaaaaa);
48 45
49static const Xsig pi_signif = MK_XSIG(0xc90fdaa2, 0x2168c234, 0xc4c6628b); 46static const Xsig pi_signif = MK_XSIG(0xc90fdaa2, 0x2168c234, 0xc4c6628b);
50 47
51
52/*--- poly_atan() -----------------------------------------------------------+ 48/*--- poly_atan() -----------------------------------------------------------+
53 | | 49 | |
54 +---------------------------------------------------------------------------*/ 50 +---------------------------------------------------------------------------*/
55void poly_atan(FPU_REG *st0_ptr, u_char st0_tag, 51void poly_atan(FPU_REG * st0_ptr, u_char st0_tag,
56 FPU_REG *st1_ptr, u_char st1_tag) 52 FPU_REG * st1_ptr, u_char st1_tag)
57{ 53{
58 u_char transformed, inverted, 54 u_char transformed, inverted, sign1, sign2;
59 sign1, sign2; 55 int exponent;
60 int exponent; 56 long int dummy_exp;
61 long int dummy_exp; 57 Xsig accumulator, Numer, Denom, accumulatore, argSignif, argSq, argSqSq;
62 Xsig accumulator, Numer, Denom, accumulatore, argSignif, 58 u_char tag;
63 argSq, argSqSq; 59
64 u_char tag; 60 sign1 = getsign(st0_ptr);
65 61 sign2 = getsign(st1_ptr);
66 sign1 = getsign(st0_ptr); 62 if (st0_tag == TAG_Valid) {
67 sign2 = getsign(st1_ptr); 63 exponent = exponent(st0_ptr);
68 if ( st0_tag == TAG_Valid ) 64 } else {
69 { 65 /* This gives non-compatible stack contents... */
70 exponent = exponent(st0_ptr); 66 FPU_to_exp16(st0_ptr, st0_ptr);
71 } 67 exponent = exponent16(st0_ptr);
72 else 68 }
73 { 69 if (st1_tag == TAG_Valid) {
74 /* This gives non-compatible stack contents... */ 70 exponent -= exponent(st1_ptr);
75 FPU_to_exp16(st0_ptr, st0_ptr); 71 } else {
76 exponent = exponent16(st0_ptr); 72 /* This gives non-compatible stack contents... */
77 } 73 FPU_to_exp16(st1_ptr, st1_ptr);
78 if ( st1_tag == TAG_Valid ) 74 exponent -= exponent16(st1_ptr);
79 { 75 }
80 exponent -= exponent(st1_ptr); 76
81 } 77 if ((exponent < 0) || ((exponent == 0) &&
82 else 78 ((st0_ptr->sigh < st1_ptr->sigh) ||
83 { 79 ((st0_ptr->sigh == st1_ptr->sigh) &&
84 /* This gives non-compatible stack contents... */ 80 (st0_ptr->sigl < st1_ptr->sigl))))) {
85 FPU_to_exp16(st1_ptr, st1_ptr); 81 inverted = 1;
86 exponent -= exponent16(st1_ptr); 82 Numer.lsw = Denom.lsw = 0;
87 } 83 XSIG_LL(Numer) = significand(st0_ptr);
88 84 XSIG_LL(Denom) = significand(st1_ptr);
89 if ( (exponent < 0) || ((exponent == 0) && 85 } else {
90 ((st0_ptr->sigh < st1_ptr->sigh) || 86 inverted = 0;
91 ((st0_ptr->sigh == st1_ptr->sigh) && 87 exponent = -exponent;
92 (st0_ptr->sigl < st1_ptr->sigl))) ) ) 88 Numer.lsw = Denom.lsw = 0;
93 { 89 XSIG_LL(Numer) = significand(st1_ptr);
94 inverted = 1; 90 XSIG_LL(Denom) = significand(st0_ptr);
95 Numer.lsw = Denom.lsw = 0; 91 }
96 XSIG_LL(Numer) = significand(st0_ptr); 92 div_Xsig(&Numer, &Denom, &argSignif);
97 XSIG_LL(Denom) = significand(st1_ptr); 93 exponent += norm_Xsig(&argSignif);
98 } 94
99 else 95 if ((exponent >= -1)
100 { 96 || ((exponent == -2) && (argSignif.msw > 0xd413ccd0))) {
101 inverted = 0; 97 /* The argument is greater than sqrt(2)-1 (=0.414213562...) */
102 exponent = -exponent; 98 /* Convert the argument by an identity for atan */
103 Numer.lsw = Denom.lsw = 0; 99 transformed = 1;
104 XSIG_LL(Numer) = significand(st1_ptr); 100
105 XSIG_LL(Denom) = significand(st0_ptr); 101 if (exponent >= 0) {
106 }
107 div_Xsig(&Numer, &Denom, &argSignif);
108 exponent += norm_Xsig(&argSignif);
109
110 if ( (exponent >= -1)
111 || ((exponent == -2) && (argSignif.msw > 0xd413ccd0)) )
112 {
113 /* The argument is greater than sqrt(2)-1 (=0.414213562...) */
114 /* Convert the argument by an identity for atan */
115 transformed = 1;
116
117 if ( exponent >= 0 )
118 {
119#ifdef PARANOID 102#ifdef PARANOID
120 if ( !( (exponent == 0) && 103 if (!((exponent == 0) &&
121 (argSignif.lsw == 0) && (argSignif.midw == 0) && 104 (argSignif.lsw == 0) && (argSignif.midw == 0) &&
122 (argSignif.msw == 0x80000000) ) ) 105 (argSignif.msw == 0x80000000))) {
123 { 106 EXCEPTION(EX_INTERNAL | 0x104); /* There must be a logic error */
124 EXCEPTION(EX_INTERNAL|0x104); /* There must be a logic error */ 107 return;
125 return; 108 }
126 }
127#endif /* PARANOID */ 109#endif /* PARANOID */
128 argSignif.msw = 0; /* Make the transformed arg -> 0.0 */ 110 argSignif.msw = 0; /* Make the transformed arg -> 0.0 */
111 } else {
112 Numer.lsw = Denom.lsw = argSignif.lsw;
113 XSIG_LL(Numer) = XSIG_LL(Denom) = XSIG_LL(argSignif);
114
115 if (exponent < -1)
116 shr_Xsig(&Numer, -1 - exponent);
117 negate_Xsig(&Numer);
118
119 shr_Xsig(&Denom, -exponent);
120 Denom.msw |= 0x80000000;
121
122 div_Xsig(&Numer, &Denom, &argSignif);
123
124 exponent = -1 + norm_Xsig(&argSignif);
125 }
126 } else {
127 transformed = 0;
128 }
129
130 argSq.lsw = argSignif.lsw;
131 argSq.midw = argSignif.midw;
132 argSq.msw = argSignif.msw;
133 mul_Xsig_Xsig(&argSq, &argSq);
134
135 argSqSq.lsw = argSq.lsw;
136 argSqSq.midw = argSq.midw;
137 argSqSq.msw = argSq.msw;
138 mul_Xsig_Xsig(&argSqSq, &argSqSq);
139
140 accumulatore.lsw = argSq.lsw;
141 XSIG_LL(accumulatore) = XSIG_LL(argSq);
142
143 shr_Xsig(&argSq, 2 * (-1 - exponent - 1));
144 shr_Xsig(&argSqSq, 4 * (-1 - exponent - 1));
145
146 /* Now have argSq etc with binary point at the left
147 .1xxxxxxxx */
148
149 /* Do the basic fixed point polynomial evaluation */
150 accumulator.msw = accumulator.midw = accumulator.lsw = 0;
151 polynomial_Xsig(&accumulator, &XSIG_LL(argSqSq),
152 oddplterms, HIPOWERop - 1);
153 mul64_Xsig(&accumulator, &XSIG_LL(argSq));
154 negate_Xsig(&accumulator);
155 polynomial_Xsig(&accumulator, &XSIG_LL(argSqSq), oddnegterms,
156 HIPOWERon - 1);
157 negate_Xsig(&accumulator);
158 add_two_Xsig(&accumulator, &fixedpterm, &dummy_exp);
159
160 mul64_Xsig(&accumulatore, &denomterm);
161 shr_Xsig(&accumulatore, 1 + 2 * (-1 - exponent));
162 accumulatore.msw |= 0x80000000;
163
164 div_Xsig(&accumulator, &accumulatore, &accumulator);
165
166 mul_Xsig_Xsig(&accumulator, &argSignif);
167 mul_Xsig_Xsig(&accumulator, &argSq);
168
169 shr_Xsig(&accumulator, 3);
170 negate_Xsig(&accumulator);
171 add_Xsig_Xsig(&accumulator, &argSignif);
172
173 if (transformed) {
174 /* compute pi/4 - accumulator */
175 shr_Xsig(&accumulator, -1 - exponent);
176 negate_Xsig(&accumulator);
177 add_Xsig_Xsig(&accumulator, &pi_signif);
178 exponent = -1;
179 }
180
181 if (inverted) {
182 /* compute pi/2 - accumulator */
183 shr_Xsig(&accumulator, -exponent);
184 negate_Xsig(&accumulator);
185 add_Xsig_Xsig(&accumulator, &pi_signif);
186 exponent = 0;
129 } 187 }
130 else 188
131 { 189 if (sign1) {
132 Numer.lsw = Denom.lsw = argSignif.lsw; 190 /* compute pi - accumulator */
133 XSIG_LL(Numer) = XSIG_LL(Denom) = XSIG_LL(argSignif); 191 shr_Xsig(&accumulator, 1 - exponent);
134 192 negate_Xsig(&accumulator);
135 if ( exponent < -1 ) 193 add_Xsig_Xsig(&accumulator, &pi_signif);
136 shr_Xsig(&Numer, -1-exponent); 194 exponent = 1;
137 negate_Xsig(&Numer);
138
139 shr_Xsig(&Denom, -exponent);
140 Denom.msw |= 0x80000000;
141
142 div_Xsig(&Numer, &Denom, &argSignif);
143
144 exponent = -1 + norm_Xsig(&argSignif);
145 } 195 }
146 } 196
147 else 197 exponent += round_Xsig(&accumulator);
148 { 198
149 transformed = 0; 199 significand(st1_ptr) = XSIG_LL(accumulator);
150 } 200 setexponent16(st1_ptr, exponent);
151 201
152 argSq.lsw = argSignif.lsw; argSq.midw = argSignif.midw; 202 tag = FPU_round(st1_ptr, 1, 0, FULL_PRECISION, sign2);
153 argSq.msw = argSignif.msw; 203 FPU_settagi(1, tag);
154 mul_Xsig_Xsig(&argSq, &argSq); 204
155 205 set_precision_flag_up(); /* We do not really know if up or down,
156 argSqSq.lsw = argSq.lsw; argSqSq.midw = argSq.midw; argSqSq.msw = argSq.msw; 206 use this as the default. */
157 mul_Xsig_Xsig(&argSqSq, &argSqSq);
158
159 accumulatore.lsw = argSq.lsw;
160 XSIG_LL(accumulatore) = XSIG_LL(argSq);
161
162 shr_Xsig(&argSq, 2*(-1-exponent-1));
163 shr_Xsig(&argSqSq, 4*(-1-exponent-1));
164
165 /* Now have argSq etc with binary point at the left
166 .1xxxxxxxx */
167
168 /* Do the basic fixed point polynomial evaluation */
169 accumulator.msw = accumulator.midw = accumulator.lsw = 0;
170 polynomial_Xsig(&accumulator, &XSIG_LL(argSqSq),
171 oddplterms, HIPOWERop-1);
172 mul64_Xsig(&accumulator, &XSIG_LL(argSq));
173 negate_Xsig(&accumulator);
174 polynomial_Xsig(&accumulator, &XSIG_LL(argSqSq), oddnegterms, HIPOWERon-1);
175 negate_Xsig(&accumulator);
176 add_two_Xsig(&accumulator, &fixedpterm, &dummy_exp);
177
178 mul64_Xsig(&accumulatore, &denomterm);
179 shr_Xsig(&accumulatore, 1 + 2*(-1-exponent));
180 accumulatore.msw |= 0x80000000;
181
182 div_Xsig(&accumulator, &accumulatore, &accumulator);
183
184 mul_Xsig_Xsig(&accumulator, &argSignif);
185 mul_Xsig_Xsig(&accumulator, &argSq);
186
187 shr_Xsig(&accumulator, 3);
188 negate_Xsig(&accumulator);
189 add_Xsig_Xsig(&accumulator, &argSignif);
190
191 if ( transformed )
192 {
193 /* compute pi/4 - accumulator */
194 shr_Xsig(&accumulator, -1-exponent);
195 negate_Xsig(&accumulator);
196 add_Xsig_Xsig(&accumulator, &pi_signif);
197 exponent = -1;
198 }
199
200 if ( inverted )
201 {
202 /* compute pi/2 - accumulator */
203 shr_Xsig(&accumulator, -exponent);
204 negate_Xsig(&accumulator);
205 add_Xsig_Xsig(&accumulator, &pi_signif);
206 exponent = 0;
207 }
208
209 if ( sign1 )
210 {
211 /* compute pi - accumulator */
212 shr_Xsig(&accumulator, 1 - exponent);
213 negate_Xsig(&accumulator);
214 add_Xsig_Xsig(&accumulator, &pi_signif);
215 exponent = 1;
216 }
217
218 exponent += round_Xsig(&accumulator);
219
220 significand(st1_ptr) = XSIG_LL(accumulator);
221 setexponent16(st1_ptr, exponent);
222
223 tag = FPU_round(st1_ptr, 1, 0, FULL_PRECISION, sign2);
224 FPU_settagi(1, tag);
225
226 set_precision_flag_up(); /* We do not really know if up or down,
227 use this as the default. */
228 207
229} 208}
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