116 lines
3.3 KiB
C
116 lines
3.3 KiB
C
/*---------------------------------------------------------------------------+
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| reg_constant.c |
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| All of the constant FPU_REGs |
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| Copyright (C) 1992,1993,1994 |
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| W. Metzenthen, 22 Parker St, Ormond, Vic 3163, |
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| Australia. E-mail billm@vaxc.cc.monash.edu.au |
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+---------------------------------------------------------------------------*/
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#include "fpu_system.h"
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#include "fpu_emu.h"
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#include "status_w.h"
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#include "reg_constant.h"
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FPU_REG const CONST_1 = { SIGN_POS, TW_Valid, EXP_BIAS,
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0x00000000, 0x80000000 };
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FPU_REG const CONST_2 = { SIGN_POS, TW_Valid, EXP_BIAS+1,
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0x00000000, 0x80000000 };
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FPU_REG const CONST_HALF = { SIGN_POS, TW_Valid, EXP_BIAS-1,
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0x00000000, 0x80000000 };
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FPU_REG const CONST_L2T = { SIGN_POS, TW_Valid, EXP_BIAS+1,
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0xcd1b8afe, 0xd49a784b };
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FPU_REG const CONST_L2E = { SIGN_POS, TW_Valid, EXP_BIAS,
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0x5c17f0bc, 0xb8aa3b29 };
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FPU_REG const CONST_PI = { SIGN_POS, TW_Valid, EXP_BIAS+1,
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0x2168c235, 0xc90fdaa2 };
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FPU_REG const CONST_PI2 = { SIGN_POS, TW_Valid, EXP_BIAS,
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0x2168c235, 0xc90fdaa2 };
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FPU_REG const CONST_PI4 = { SIGN_POS, TW_Valid, EXP_BIAS-1,
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0x2168c235, 0xc90fdaa2 };
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FPU_REG const CONST_LG2 = { SIGN_POS, TW_Valid, EXP_BIAS-2,
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0xfbcff799, 0x9a209a84 };
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FPU_REG const CONST_LN2 = { SIGN_POS, TW_Valid, EXP_BIAS-1,
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0xd1cf79ac, 0xb17217f7 };
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/* Extra bits to take pi/2 to more than 128 bits precision. */
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FPU_REG const CONST_PI2extra = { SIGN_NEG, TW_Valid, EXP_BIAS-66,
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0xfc8f8cbb, 0xece675d1 };
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/* Only the sign (and tag) is used in internal zeroes */
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FPU_REG const CONST_Z = { SIGN_POS, TW_Zero, EXP_UNDER, 0x0, 0x0 };
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/* Only the sign and significand (and tag) are used in internal NaNs */
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/* The 80486 never generates one of these
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FPU_REG const CONST_SNAN = { SIGN_POS, TW_NaN, EXP_OVER, 0x00000001, 0x80000000 };
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*/
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/* This is the real indefinite QNaN */
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FPU_REG const CONST_QNaN = { SIGN_NEG, TW_NaN, EXP_OVER, 0x00000000, 0xC0000000 };
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/* Only the sign (and tag) is used in internal infinities */
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FPU_REG const CONST_INF = { SIGN_POS, TW_Infinity, EXP_OVER, 0x00000000, 0x80000000 };
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static void fld_const(FPU_REG const *c)
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{
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FPU_REG *st_new_ptr;
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if ( STACK_OVERFLOW )
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{
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stack_overflow();
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return;
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}
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push();
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reg_move(c, FPU_st0_ptr);
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clear_C1();
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}
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static void fld1(void)
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{
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fld_const(&CONST_1);
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}
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static void fldl2t(void)
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{
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fld_const(&CONST_L2T);
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}
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static void fldl2e(void)
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{
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fld_const(&CONST_L2E);
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}
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static void fldpi(void)
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{
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fld_const(&CONST_PI);
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}
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static void fldlg2(void)
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{
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fld_const(&CONST_LG2);
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}
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static void fldln2(void)
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{
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fld_const(&CONST_LN2);
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}
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static void fldz(void)
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{
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fld_const(&CONST_Z);
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}
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static FUNC constants_table[] = {
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fld1, fldl2t, fldl2e, fldpi, fldlg2, fldln2, fldz, FPU_illegal
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};
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void fconst(void)
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{
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(constants_table[FPU_rm])();
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}
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