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-rw-r--r--qemu/libdecnumber/decContext.c433
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diff --git a/qemu/libdecnumber/decContext.c b/qemu/libdecnumber/decContext.c
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+/* Decimal context module for the decNumber C Library.
+ Copyright (C) 2005, 2007 Free Software Foundation, Inc.
+ Contributed by IBM Corporation. Author Mike Cowlishaw.
+
+ This file is part of GCC.
+
+ GCC is free software; you can redistribute it and/or modify it under
+ the terms of the GNU General Public License as published by the Free
+ Software Foundation; either version 2, or (at your option) any later
+ version.
+
+ In addition to the permissions in the GNU General Public License,
+ the Free Software Foundation gives you unlimited permission to link
+ the compiled version of this file into combinations with other
+ programs, and to distribute those combinations without any
+ restriction coming from the use of this file. (The General Public
+ License restrictions do apply in other respects; for example, they
+ cover modification of the file, and distribution when not linked
+ into a combine executable.)
+
+ GCC is distributed in the hope that it will be useful, but WITHOUT ANY
+ WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
+ for more details.
+
+ You should have received a copy of the GNU General Public License
+ along with GCC; see the file COPYING. If not, write to the Free
+ Software Foundation, 51 Franklin Street, Fifth Floor, Boston, MA
+ 02110-1301, USA. */
+
+/* ------------------------------------------------------------------ */
+/* Decimal Context module */
+/* ------------------------------------------------------------------ */
+/* This module comprises the routines for handling arithmetic */
+/* context structures. */
+/* ------------------------------------------------------------------ */
+
+#include <string.h> /* for strcmp */
+#include <stdio.h> /* for printf if DECCHECK */
+#include "libdecnumber/dconfig.h"
+#include "libdecnumber/decContext.h"
+#include "libdecnumber/decNumberLocal.h"
+
+#if DECCHECK
+/* compile-time endian tester [assumes sizeof(Int)>1] */
+static const Int mfcone=1; /* constant 1 */
+static const Flag *mfctop=(Flag *)&mfcone; /* -> top byte */
+#define LITEND *mfctop /* named flag; 1=little-endian */
+#endif
+
+/* ------------------------------------------------------------------ */
+/* round-for-reround digits */
+/* ------------------------------------------------------------------ */
+const uByte DECSTICKYTAB[10]={1,1,2,3,4,6,6,7,8,9}; /* used if sticky */
+
+/* ------------------------------------------------------------------ */
+/* Powers of ten (powers[n]==10**n, 0<=n<=9) */
+/* ------------------------------------------------------------------ */
+const uLong DECPOWERS[19] = {1, 10, 100, 1000, 10000, 100000, 1000000,
+ 10000000, 100000000, 1000000000, 10000000000ULL, 100000000000ULL,
+ 1000000000000ULL, 10000000000000ULL, 100000000000000ULL, 1000000000000000ULL,
+ 10000000000000000ULL, 100000000000000000ULL, 1000000000000000000ULL, };
+
+/* ------------------------------------------------------------------ */
+/* decContextClearStatus -- clear bits in current status */
+/* */
+/* context is the context structure to be queried */
+/* mask indicates the bits to be cleared (the status bit that */
+/* corresponds to each 1 bit in the mask is cleared) */
+/* returns context */
+/* */
+/* No error is possible. */
+/* ------------------------------------------------------------------ */
+decContext *decContextClearStatus(decContext *context, uInt mask) {
+ context->status&=~mask;
+ return context;
+ } /* decContextClearStatus */
+
+/* ------------------------------------------------------------------ */
+/* decContextDefault -- initialize a context structure */
+/* */
+/* context is the structure to be initialized */
+/* kind selects the required set of default values, one of: */
+/* DEC_INIT_BASE -- select ANSI X3-274 defaults */
+/* DEC_INIT_DECIMAL32 -- select IEEE 754r defaults, 32-bit */
+/* DEC_INIT_DECIMAL64 -- select IEEE 754r defaults, 64-bit */
+/* DEC_INIT_DECIMAL128 -- select IEEE 754r defaults, 128-bit */
+/* For any other value a valid context is returned, but with */
+/* Invalid_operation set in the status field. */
+/* returns a context structure with the appropriate initial values. */
+/* ------------------------------------------------------------------ */
+decContext * decContextDefault(decContext *context, Int kind) {
+ /* set defaults... */
+ context->digits=9; /* 9 digits */
+ context->emax=DEC_MAX_EMAX; /* 9-digit exponents */
+ context->emin=DEC_MIN_EMIN; /* .. balanced */
+ context->round=DEC_ROUND_HALF_UP; /* 0.5 rises */
+ context->traps=DEC_Errors; /* all but informational */
+ context->status=0; /* cleared */
+ context->clamp=0; /* no clamping */
+ #if DECSUBSET
+ context->extended=0; /* cleared */
+ #endif
+ switch (kind) {
+ case DEC_INIT_BASE:
+ /* [use defaults] */
+ break;
+ case DEC_INIT_DECIMAL32:
+ context->digits=7; /* digits */
+ context->emax=96; /* Emax */
+ context->emin=-95; /* Emin */
+ context->round=DEC_ROUND_HALF_EVEN; /* 0.5 to nearest even */
+ context->traps=0; /* no traps set */
+ context->clamp=1; /* clamp exponents */
+ #if DECSUBSET
+ context->extended=1; /* set */
+ #endif
+ break;
+ case DEC_INIT_DECIMAL64:
+ context->digits=16; /* digits */
+ context->emax=384; /* Emax */
+ context->emin=-383; /* Emin */
+ context->round=DEC_ROUND_HALF_EVEN; /* 0.5 to nearest even */
+ context->traps=0; /* no traps set */
+ context->clamp=1; /* clamp exponents */
+ #if DECSUBSET
+ context->extended=1; /* set */
+ #endif
+ break;
+ case DEC_INIT_DECIMAL128:
+ context->digits=34; /* digits */
+ context->emax=6144; /* Emax */
+ context->emin=-6143; /* Emin */
+ context->round=DEC_ROUND_HALF_EVEN; /* 0.5 to nearest even */
+ context->traps=0; /* no traps set */
+ context->clamp=1; /* clamp exponents */
+ #if DECSUBSET
+ context->extended=1; /* set */
+ #endif
+ break;
+
+ default: /* invalid Kind */
+ /* use defaults, and .. */
+ decContextSetStatus(context, DEC_Invalid_operation); /* trap */
+ }
+
+ #if DECCHECK
+ if (LITEND!=DECLITEND) {
+ const char *adj;
+ if (LITEND) adj="little";
+ else adj="big";
+ printf("Warning: DECLITEND is set to %d, but this computer appears to be %s-endian\n",
+ DECLITEND, adj);
+ }
+ #endif
+ return context;} /* decContextDefault */
+
+/* ------------------------------------------------------------------ */
+/* decContextGetRounding -- return current rounding mode */
+/* */
+/* context is the context structure to be queried */
+/* returns the rounding mode */
+/* */
+/* No error is possible. */
+/* ------------------------------------------------------------------ */
+enum rounding decContextGetRounding(decContext *context) {
+ return context->round;
+ } /* decContextGetRounding */
+
+/* ------------------------------------------------------------------ */
+/* decContextGetStatus -- return current status */
+/* */
+/* context is the context structure to be queried */
+/* returns status */
+/* */
+/* No error is possible. */
+/* ------------------------------------------------------------------ */
+uInt decContextGetStatus(decContext *context) {
+ return context->status;
+ } /* decContextGetStatus */
+
+/* ------------------------------------------------------------------ */
+/* decContextRestoreStatus -- restore bits in current status */
+/* */
+/* context is the context structure to be updated */
+/* newstatus is the source for the bits to be restored */
+/* mask indicates the bits to be restored (the status bit that */
+/* corresponds to each 1 bit in the mask is set to the value of */
+/* the correspnding bit in newstatus) */
+/* returns context */
+/* */
+/* No error is possible. */
+/* ------------------------------------------------------------------ */
+decContext *decContextRestoreStatus(decContext *context,
+ uInt newstatus, uInt mask) {
+ context->status&=~mask; /* clear the selected bits */
+ context->status|=(mask&newstatus); /* or in the new bits */
+ return context;
+ } /* decContextRestoreStatus */
+
+/* ------------------------------------------------------------------ */
+/* decContextSaveStatus -- save bits in current status */
+/* */
+/* context is the context structure to be queried */
+/* mask indicates the bits to be saved (the status bits that */
+/* correspond to each 1 bit in the mask are saved) */
+/* returns the AND of the mask and the current status */
+/* */
+/* No error is possible. */
+/* ------------------------------------------------------------------ */
+uInt decContextSaveStatus(decContext *context, uInt mask) {
+ return context->status&mask;
+ } /* decContextSaveStatus */
+
+/* ------------------------------------------------------------------ */
+/* decContextSetRounding -- set current rounding mode */
+/* */
+/* context is the context structure to be updated */
+/* newround is the value which will replace the current mode */
+/* returns context */
+/* */
+/* No error is possible. */
+/* ------------------------------------------------------------------ */
+decContext *decContextSetRounding(decContext *context,
+ enum rounding newround) {
+ context->round=newround;
+ return context;
+ } /* decContextSetRounding */
+
+/* ------------------------------------------------------------------ */
+/* decContextSetStatus -- set status and raise trap if appropriate */
+/* */
+/* context is the context structure to be updated */
+/* status is the DEC_ exception code */
+/* returns the context structure */
+/* */
+/* Control may never return from this routine, if there is a signal */
+/* handler and it takes a long jump. */
+/* ------------------------------------------------------------------ */
+decContext * decContextSetStatus(decContext *context, uInt status) {
+ context->status|=status;
+ if (status & context->traps) raise(SIGFPE);
+ return context;} /* decContextSetStatus */
+
+/* ------------------------------------------------------------------ */
+/* decContextSetStatusFromString -- set status from a string + trap */
+/* */
+/* context is the context structure to be updated */
+/* string is a string exactly equal to one that might be returned */
+/* by decContextStatusToString */
+/* */
+/* The status bit corresponding to the string is set, and a trap */
+/* is raised if appropriate. */
+/* */
+/* returns the context structure, unless the string is equal to */
+/* DEC_Condition_MU or is not recognized. In these cases NULL is */
+/* returned. */
+/* ------------------------------------------------------------------ */
+decContext * decContextSetStatusFromString(decContext *context,
+ const char *string) {
+ if (strcmp(string, DEC_Condition_CS)==0)
+ return decContextSetStatus(context, DEC_Conversion_syntax);
+ if (strcmp(string, DEC_Condition_DZ)==0)
+ return decContextSetStatus(context, DEC_Division_by_zero);
+ if (strcmp(string, DEC_Condition_DI)==0)
+ return decContextSetStatus(context, DEC_Division_impossible);
+ if (strcmp(string, DEC_Condition_DU)==0)
+ return decContextSetStatus(context, DEC_Division_undefined);
+ if (strcmp(string, DEC_Condition_IE)==0)
+ return decContextSetStatus(context, DEC_Inexact);
+ if (strcmp(string, DEC_Condition_IS)==0)
+ return decContextSetStatus(context, DEC_Insufficient_storage);
+ if (strcmp(string, DEC_Condition_IC)==0)
+ return decContextSetStatus(context, DEC_Invalid_context);
+ if (strcmp(string, DEC_Condition_IO)==0)
+ return decContextSetStatus(context, DEC_Invalid_operation);
+ #if DECSUBSET
+ if (strcmp(string, DEC_Condition_LD)==0)
+ return decContextSetStatus(context, DEC_Lost_digits);
+ #endif
+ if (strcmp(string, DEC_Condition_OV)==0)
+ return decContextSetStatus(context, DEC_Overflow);
+ if (strcmp(string, DEC_Condition_PA)==0)
+ return decContextSetStatus(context, DEC_Clamped);
+ if (strcmp(string, DEC_Condition_RO)==0)
+ return decContextSetStatus(context, DEC_Rounded);
+ if (strcmp(string, DEC_Condition_SU)==0)
+ return decContextSetStatus(context, DEC_Subnormal);
+ if (strcmp(string, DEC_Condition_UN)==0)
+ return decContextSetStatus(context, DEC_Underflow);
+ if (strcmp(string, DEC_Condition_ZE)==0)
+ return context;
+ return NULL; /* Multiple status, or unknown */
+ } /* decContextSetStatusFromString */
+
+/* ------------------------------------------------------------------ */
+/* decContextSetStatusFromStringQuiet -- set status from a string */
+/* */
+/* context is the context structure to be updated */
+/* string is a string exactly equal to one that might be returned */
+/* by decContextStatusToString */
+/* */
+/* The status bit corresponding to the string is set; no trap is */
+/* raised. */
+/* */
+/* returns the context structure, unless the string is equal to */
+/* DEC_Condition_MU or is not recognized. In these cases NULL is */
+/* returned. */
+/* ------------------------------------------------------------------ */
+decContext * decContextSetStatusFromStringQuiet(decContext *context,
+ const char *string) {
+ if (strcmp(string, DEC_Condition_CS)==0)
+ return decContextSetStatusQuiet(context, DEC_Conversion_syntax);
+ if (strcmp(string, DEC_Condition_DZ)==0)
+ return decContextSetStatusQuiet(context, DEC_Division_by_zero);
+ if (strcmp(string, DEC_Condition_DI)==0)
+ return decContextSetStatusQuiet(context, DEC_Division_impossible);
+ if (strcmp(string, DEC_Condition_DU)==0)
+ return decContextSetStatusQuiet(context, DEC_Division_undefined);
+ if (strcmp(string, DEC_Condition_IE)==0)
+ return decContextSetStatusQuiet(context, DEC_Inexact);
+ if (strcmp(string, DEC_Condition_IS)==0)
+ return decContextSetStatusQuiet(context, DEC_Insufficient_storage);
+ if (strcmp(string, DEC_Condition_IC)==0)
+ return decContextSetStatusQuiet(context, DEC_Invalid_context);
+ if (strcmp(string, DEC_Condition_IO)==0)
+ return decContextSetStatusQuiet(context, DEC_Invalid_operation);
+ #if DECSUBSET
+ if (strcmp(string, DEC_Condition_LD)==0)
+ return decContextSetStatusQuiet(context, DEC_Lost_digits);
+ #endif
+ if (strcmp(string, DEC_Condition_OV)==0)
+ return decContextSetStatusQuiet(context, DEC_Overflow);
+ if (strcmp(string, DEC_Condition_PA)==0)
+ return decContextSetStatusQuiet(context, DEC_Clamped);
+ if (strcmp(string, DEC_Condition_RO)==0)
+ return decContextSetStatusQuiet(context, DEC_Rounded);
+ if (strcmp(string, DEC_Condition_SU)==0)
+ return decContextSetStatusQuiet(context, DEC_Subnormal);
+ if (strcmp(string, DEC_Condition_UN)==0)
+ return decContextSetStatusQuiet(context, DEC_Underflow);
+ if (strcmp(string, DEC_Condition_ZE)==0)
+ return context;
+ return NULL; /* Multiple status, or unknown */
+ } /* decContextSetStatusFromStringQuiet */
+
+/* ------------------------------------------------------------------ */
+/* decContextSetStatusQuiet -- set status without trap */
+/* */
+/* context is the context structure to be updated */
+/* status is the DEC_ exception code */
+/* returns the context structure */
+/* */
+/* No error is possible. */
+/* ------------------------------------------------------------------ */
+decContext * decContextSetStatusQuiet(decContext *context, uInt status) {
+ context->status|=status;
+ return context;} /* decContextSetStatusQuiet */
+
+/* ------------------------------------------------------------------ */
+/* decContextStatusToString -- convert status flags to a string */
+/* */
+/* context is a context with valid status field */
+/* */
+/* returns a constant string describing the condition. If multiple */
+/* (or no) flags are set, a generic constant message is returned. */
+/* ------------------------------------------------------------------ */
+const char *decContextStatusToString(const decContext *context) {
+ Int status=context->status;
+
+ /* test the five IEEE first, as some of the others are ambiguous when */
+ /* DECEXTFLAG=0 */
+ if (status==DEC_Invalid_operation ) return DEC_Condition_IO;
+ if (status==DEC_Division_by_zero ) return DEC_Condition_DZ;
+ if (status==DEC_Overflow ) return DEC_Condition_OV;
+ if (status==DEC_Underflow ) return DEC_Condition_UN;
+ if (status==DEC_Inexact ) return DEC_Condition_IE;
+
+ if (status==DEC_Division_impossible ) return DEC_Condition_DI;
+ if (status==DEC_Division_undefined ) return DEC_Condition_DU;
+ if (status==DEC_Rounded ) return DEC_Condition_RO;
+ if (status==DEC_Clamped ) return DEC_Condition_PA;
+ if (status==DEC_Subnormal ) return DEC_Condition_SU;
+ if (status==DEC_Conversion_syntax ) return DEC_Condition_CS;
+ if (status==DEC_Insufficient_storage ) return DEC_Condition_IS;
+ if (status==DEC_Invalid_context ) return DEC_Condition_IC;
+ #if DECSUBSET
+ if (status==DEC_Lost_digits ) return DEC_Condition_LD;
+ #endif
+ if (status==0 ) return DEC_Condition_ZE;
+ return DEC_Condition_MU; /* Multiple errors */
+ } /* decContextStatusToString */
+
+/* ------------------------------------------------------------------ */
+/* decContextTestSavedStatus -- test bits in saved status */
+/* */
+/* oldstatus is the status word to be tested */
+/* mask indicates the bits to be tested (the oldstatus bits that */
+/* correspond to each 1 bit in the mask are tested) */
+/* returns 1 if any of the tested bits are 1, or 0 otherwise */
+/* */
+/* No error is possible. */
+/* ------------------------------------------------------------------ */
+uInt decContextTestSavedStatus(uInt oldstatus, uInt mask) {
+ return (oldstatus&mask)!=0;
+ } /* decContextTestSavedStatus */
+
+/* ------------------------------------------------------------------ */
+/* decContextTestStatus -- test bits in current status */
+/* */
+/* context is the context structure to be updated */
+/* mask indicates the bits to be tested (the status bits that */
+/* correspond to each 1 bit in the mask are tested) */
+/* returns 1 if any of the tested bits are 1, or 0 otherwise */
+/* */
+/* No error is possible. */
+/* ------------------------------------------------------------------ */
+uInt decContextTestStatus(decContext *context, uInt mask) {
+ return (context->status&mask)!=0;
+ } /* decContextTestStatus */
+
+/* ------------------------------------------------------------------ */
+/* decContextZeroStatus -- clear all status bits */
+/* */
+/* context is the context structure to be updated */
+/* returns context */
+/* */
+/* No error is possible. */
+/* ------------------------------------------------------------------ */
+decContext *decContextZeroStatus(decContext *context) {
+ context->status=0;
+ return context;
+ } /* decContextZeroStatus */