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|
; Zilog eZ80 ANSI C Compiler Release 3.4
; -optsize -nomodsect -peephole -globalopt -localcse
; -const=ROM
FILE "..\GAMMA.C"
.assume ADL=1
SEGMENT CODE
; 1 /*
; 2 * gamma.c - public domain implementation of function tgamma(3m)
; 3 * reference - Haruhiko Okumura: C-gengo niyoru saishin algorithm jiten
; 4 * (New Algorithm handbook in C language) (Gijyutsu hyouronsha, Tokyo, 1991) [in Japanese]
; 5 * http://oku.edu.mie-u.ac.jp/~okumura/algo/
; 6 */
; 7
; 8 #include <math.h>
; 9 #include <errno.h>
; 10
; 11 #define N 8
; 12
; 13 #define B0 1 /* Bernoulli numbers */
; 14 #define B1 (-1.0 / 2.0)
; 15 #define B2 ( 1.0 / 6.0)
; 16 #define B4 (-1.0 / 30.0)
; 17 #define B6 ( 1.0 / 42.0)
; 18 #define B8 (-1.0 / 30.0)
; 19 #define B10 ( 5.0 / 66.0)
; 20 #define B12 (-691.0 / 2730.0)
; 21 #define B14 ( 7.0 / 6.0)
; 22 #define B16 (-3617.0 / 510.0)
; 23
; 24 static double loggamma(double x) { /* the natural logarithm of the Gamma function. */
_loggamma:
LD HL,-22
CALL __frameset
; 25 double v, w;
; 26
; 27 v = 1;
LD BC,8388608
LD (IX+-8),BC
LD A,63
LD (IX+-5),A
; 28 while (x < N) { v *= x; x++; }
JR L_1
L_2:
LD HL,(IX+6)
LD E,(IX+9)
LD BC,(IX+-8)
LD A,(IX+-5)
CALL __fmul
LD (IX+-8),BC
LD (IX+-5),A
LD BC,(IX+6)
LD A,(IX+9)
LD HL,8388608
LD E,63
CALL __fadd
LD (IX+6),BC
LD (IX+9),A
L_1:
LD HL,(IX+6)
LD E,(IX+9)
LD BC,0
LD A,65
CALL __fcmp
JP M,L_2
; 29 w = 1 / (x * x);
LD HL,(IX+6)
LD E,(IX+9)
LD BC,(IX+6)
LD A,(IX+9)
CALL __fmul
LD E,A
LD HL,BC
LD BC,8388608
LD A,63
CALL __fdiv
LD (IX+-4),BC
LD (IX+-1),A
; 30 return ((((((((B16 / (16 * 15)) * w + (B14 / (14 * 13))) * w
; 31 + (B12 / (12 * 11))) * w + (B10 / (10 * 9))) * w
; 32 + (B8 / ( 8 * 7))) * w + (B6 / ( 6 * 5))) * w
; 33 + (B4 / ( 4 * 3))) * w + (B2 / ( 2 * 1))) / x
; 34 + 0.5 * M_LOG_2M_PI - log(v) - x + (x - 0.5) * log(x);
LD HL,15864886
LD E,188
CALL __fmul
LD HL,13765920
LD E,59
CALL __fadd
LD HL,(IX+-4)
LD E,(IX+-1)
CALL __fmul
LD HL,16471432
LD E,186
CALL __fadd
LD HL,(IX+-4)
LD E,(IX+-1)
CALL __fmul
LD HL,6072562
LD E,58
CALL __fadd
LD HL,(IX+-4)
LD E,(IX+-1)
CALL __fmul
LD HL,1837505
LD E,186
CALL __fadd
LD HL,(IX+-4)
LD E,(IX+-1)
CALL __fmul
LD HL,5246209
LD E,58
CALL __fadd
LD HL,(IX+-4)
LD E,(IX+-1)
CALL __fmul
LD HL,3541857
LD E,187
CALL __fadd
LD HL,(IX+-4)
LD E,(IX+-1)
CALL __fmul
LD HL,11184811
LD E,61
CALL __fadd
LD HL,(IX+6)
LD E,(IX+9)
CALL __fdiv
LD HL,7028622
LD E,63
CALL __fadd
LD (IX+-12),BC
LD C,(IX+-5)
LD B,0
PUSH BC
LD BC,(IX+-8)
PUSH BC
LD (IX+-9),A
CALL _log
POP BC
POP BC
LD A,E
LD BC,HL
LD HL,(IX+6)
LD E,(IX+9)
CALL __fadd
LD E,A
LD HL,BC
LD BC,(IX+-12)
LD A,(IX+-9)
CALL __fsub
LD (IX+-19),A
LD (IX+-18),BC
LD BC,(IX+6)
LD A,(IX+9)
OR A,A
SBC HL,HL
LD E,63
CALL __fsub
LD (IX+-15),BC
LD C,(IX+9)
LD B,0
PUSH BC
LD BC,(IX+6)
PUSH BC
LD B,A
LD (IX+-22),BC
CALL _log
LD BC,(IX+-22)
POP IY
POP IY
LD A,B
LD BC,(IX+-15)
CALL __fmul
LD E,A
LD A,(IX+-19)
LD HL,BC
LD BC,(IX+-18)
CALL __fadd
LD E,A
LD HL,BC
; 35 }
LD SP,IX
POP IX
RET
;**************************** _loggamma ***************************
;Name Addr/Register Size Type
;_log IMPORT ----- function
;v IX-8 4 variable
;w IX-4 4 variable
;x IX+6 4 parameter
; Stack Frame Size: 34 (bytes)
; Spill Code: 0 (instruction)
; 36
; 37 double tgamma(double x) { /* Gamma function */
_tgamma:
LD HL,-26
CALL __frameset
; 38 if (x == 0.0) { /* Pole Error */
LD HL,(IX+6)
LD E,(IX+9)
LD BC,0
XOR A,A
CALL __fcmp
JR NZ,L_17
; 39 errno = ERANGE;
LD BC,5
LD (_errno),BC
; 40 return 1/x < 0 ? -HUGE_VAL : HUGE_VAL;
LD HL,(IX+6)
LD E,(IX+9)
LD BC,8388608
LD A,63
CALL __fdiv
LD E,A
LD HL,BC
LD BC,0
XOR A,A
CALL __fcmp
JP P,L_7
LD BC,(__huge_val)
LD A,(__huge_val+3)
CALL __fneg
LD (IX+-14),BC
LD (IX+-11),A
JR L_8
L_7:
LD BC,(__huge_val)
LD A,(__huge_val+3)
LD (IX+-14),BC
LD (IX+-11),A
L_8:
LD HL,(IX+-14)
LD E,(IX+-11)
JR L_19
; 41 }
L_17:
; 42 if (x < 0) {
LD HL,(IX+6)
LD E,(IX+9)
XOR A,A
CALL __fcmp
JP P,L_18
; 43 int sign;
; 44 static double zero = 0.0;
; 45 double i, f;
; 46 f = modf(-x, &i);
PEA IX+-18
LD BC,(IX+6)
LD A,(IX+9)
CALL __fneg
LD DE,BC
LD C,A
LD B,0
PUSH BC
PUSH DE
CALL _modf
POP BC
POP BC
POP BC
LD (IX+-10),HL
LD (IX+-7),E
; 47 if (f == 0.0) { /* Domain Error */
LD HL,(IX+-10)
LD E,(IX+-7)
LD BC,0
XOR A,A
CALL __fcmp
JR NZ,L_15
; 48 errno = EDOM;
LD BC,4
LD (_errno),BC
; 49 return zero/zero;
LD HL,(_0zero)
LD A,(_0zero+3)
LD E,A
LD A,(_0zero+3)
LD BC,(_0zero)
CALL __fdiv
LD E,A
LD HL,BC
JR L_19
; 50 }
L_15:
; 51 sign = (fmod(i, 2.0) != 0.0) ? 1 : -1;
LD C,64
LD B,0
PUSH BC
LD BC,0
PUSH BC
LD C,(IX+-15)
LD B,0
PUSH BC
LD BC,(IX+-18)
PUSH BC
CALL _fmod
POP BC
POP BC
POP BC
POP BC
LD BC,0
XOR A,A
CALL __fcmp
JR Z,L_13
LD BC,1
LD (IX+-3),BC
JR L_14
L_13:
LD BC,16777215
LD (IX+-3),BC
L_14:
LD BC,(IX+-3)
LD (IX+-6),BC
; 52 return sign * M_PI / (sin(M_PI * f) * exp(loggamma(1 - x)));
CALL __itol
CALL __ltof
LD HL,4788187
LD E,64
CALL __fmul
LD (IX+-22),A
LD (IX+-21),BC
LD BC,(IX+-10)
LD A,(IX+-7)
LD HL,4788187
LD E,64
CALL __fmul
LD DE,BC
LD C,A
LD B,0
PUSH BC
PUSH DE
CALL _sin
POP BC
POP BC
LD (IX+-26),E
LD (IX+-25),HL
LD HL,(IX+6)
LD E,(IX+9)
LD BC,8388608
LD A,63
CALL __fsub
LD DE,BC
LD C,A
LD B,0
PUSH BC
PUSH DE
CALL _loggamma
POP BC
POP BC
LD C,E
LD B,0
PUSH BC
PUSH HL
CALL _exp
POP BC
POP BC
LD A,(IX+-26)
LD BC,(IX+-25)
CALL __fmul
LD E,A
LD A,(IX+-22)
LD HL,BC
LD BC,(IX+-21)
CALL __fdiv
LD E,A
LD HL,BC
JR L_19
; 53 }
L_18:
; 54 return exp(loggamma(x));
LD C,(IX+9)
LD B,0
PUSH BC
LD BC,(IX+6)
PUSH BC
CALL _loggamma
POP BC
POP BC
LD C,E
LD B,0
PUSH BC
PUSH HL
CALL _exp
POP BC
POP BC
; 55 }
L_19:
LD SP,IX
POP IX
RET
;**************************** _tgamma ***************************
;Name Addr/Register Size Type
;_exp IMPORT ----- function
;_sin IMPORT ----- function
;_fmod IMPORT ----- function
;_0zero STATIC 4 variable
;_modf IMPORT ----- function
;__huge_val IMPORT 4 variable
;_errno IMPORT 3 variable
;i IX-18 4 variable
;temp5 IX-14 4 variable
;f IX-10 4 variable
;sign IX-6 3 variable
;temp11 IX-3 3 variable
;x IX+6 4 parameter
; Stack Frame Size: 38 (bytes)
; Spill Code: 0 (instruction)
SEGMENT DATA
_0zero:
DF 0.0
XREF _errno:ROM
XREF _modf:ROM
XREF _fmod:ROM
XREF _log:ROM
XREF _exp:ROM
XREF _sin:ROM
XREF __huge_val:ROM
XREF __fadd:ROM
XREF __fsub:ROM
XREF __fmul:ROM
XREF __fdiv:ROM
XREF __fneg:ROM
XREF __fcmp:ROM
XREF __ltof:ROM
XREF __itol:ROM
XREF __frameset:ROM
XDEF _tgamma
END
|