| /* numeric.c |
| * |
| * Copyright (C) 1993, 1994, 1995, 1996, 1997, 1998, 1999, 2000, 2001, |
| * 2002, 2003, 2004, 2005, 2006, 2007, 2008 by Larry Wall and others |
| * |
| * You may distribute under the terms of either the GNU General Public |
| * License or the Artistic License, as specified in the README file. |
| * |
| */ |
| |
| /* |
| * "That only makes eleven (plus one mislaid) and not fourteen, |
| * unless wizards count differently to other people." --Beorn |
| * |
| * [p.115 of _The Hobbit_: "Queer Lodgings"] |
| */ |
| |
| /* |
| =head1 Numeric functions |
| |
| This file contains all the stuff needed by perl for manipulating numeric |
| values, including such things as replacements for the OS's atof() function |
| |
| =cut |
| |
| */ |
| |
| #include "EXTERN.h" |
| #define PERL_IN_NUMERIC_C |
| #include "perl.h" |
| |
| U32 |
| Perl_cast_ulong(pTHX_ NV f) |
| { |
| PERL_UNUSED_CONTEXT; |
| if (f < 0.0) |
| return f < I32_MIN ? (U32) I32_MIN : (U32)(I32) f; |
| if (f < U32_MAX_P1) { |
| #if CASTFLAGS & 2 |
| if (f < U32_MAX_P1_HALF) |
| return (U32) f; |
| f -= U32_MAX_P1_HALF; |
| return ((U32) f) | (1 + U32_MAX >> 1); |
| #else |
| return (U32) f; |
| #endif |
| } |
| return f > 0 ? U32_MAX : 0 /* NaN */; |
| } |
| |
| I32 |
| Perl_cast_i32(pTHX_ NV f) |
| { |
| PERL_UNUSED_CONTEXT; |
| if (f < I32_MAX_P1) |
| return f < I32_MIN ? I32_MIN : (I32) f; |
| if (f < U32_MAX_P1) { |
| #if CASTFLAGS & 2 |
| if (f < U32_MAX_P1_HALF) |
| return (I32)(U32) f; |
| f -= U32_MAX_P1_HALF; |
| return (I32)(((U32) f) | (1 + U32_MAX >> 1)); |
| #else |
| return (I32)(U32) f; |
| #endif |
| } |
| return f > 0 ? (I32)U32_MAX : 0 /* NaN */; |
| } |
| |
| IV |
| Perl_cast_iv(pTHX_ NV f) |
| { |
| PERL_UNUSED_CONTEXT; |
| if (f < IV_MAX_P1) |
| return f < IV_MIN ? IV_MIN : (IV) f; |
| if (f < UV_MAX_P1) { |
| #if CASTFLAGS & 2 |
| /* For future flexibility allowing for sizeof(UV) >= sizeof(IV) */ |
| if (f < UV_MAX_P1_HALF) |
| return (IV)(UV) f; |
| f -= UV_MAX_P1_HALF; |
| return (IV)(((UV) f) | (1 + UV_MAX >> 1)); |
| #else |
| return (IV)(UV) f; |
| #endif |
| } |
| return f > 0 ? (IV)UV_MAX : 0 /* NaN */; |
| } |
| |
| UV |
| Perl_cast_uv(pTHX_ NV f) |
| { |
| PERL_UNUSED_CONTEXT; |
| if (f < 0.0) |
| return f < IV_MIN ? (UV) IV_MIN : (UV)(IV) f; |
| if (f < UV_MAX_P1) { |
| #if CASTFLAGS & 2 |
| if (f < UV_MAX_P1_HALF) |
| return (UV) f; |
| f -= UV_MAX_P1_HALF; |
| return ((UV) f) | (1 + UV_MAX >> 1); |
| #else |
| return (UV) f; |
| #endif |
| } |
| return f > 0 ? UV_MAX : 0 /* NaN */; |
| } |
| |
| /* |
| =for apidoc grok_bin |
| |
| converts a string representing a binary number to numeric form. |
| |
| On entry I<start> and I<*len> give the string to scan, I<*flags> gives |
| conversion flags, and I<result> should be NULL or a pointer to an NV. |
| The scan stops at the end of the string, or the first invalid character. |
| Unless C<PERL_SCAN_SILENT_ILLDIGIT> is set in I<*flags>, encountering an |
| invalid character will also trigger a warning. |
| On return I<*len> is set to the length of the scanned string, |
| and I<*flags> gives output flags. |
| |
| If the value is <= C<UV_MAX> it is returned as a UV, the output flags are clear, |
| and nothing is written to I<*result>. If the value is > UV_MAX C<grok_bin> |
| returns UV_MAX, sets C<PERL_SCAN_GREATER_THAN_UV_MAX> in the output flags, |
| and writes the value to I<*result> (or the value is discarded if I<result> |
| is NULL). |
| |
| The binary number may optionally be prefixed with "0b" or "b" unless |
| C<PERL_SCAN_DISALLOW_PREFIX> is set in I<*flags> on entry. If |
| C<PERL_SCAN_ALLOW_UNDERSCORES> is set in I<*flags> then the binary |
| number may use '_' characters to separate digits. |
| |
| =cut |
| |
| Not documented yet because experimental is C<PERL_SCAN_SILENT_NON_PORTABLE |
| which suppresses any message for non-portable numbers that are still valid |
| on this platform. |
| */ |
| |
| UV |
| Perl_grok_bin(pTHX_ const char *start, STRLEN *len_p, I32 *flags, NV *result) |
| { |
| const char *s = start; |
| STRLEN len = *len_p; |
| UV value = 0; |
| NV value_nv = 0; |
| |
| const UV max_div_2 = UV_MAX / 2; |
| const bool allow_underscores = cBOOL(*flags & PERL_SCAN_ALLOW_UNDERSCORES); |
| bool overflowed = FALSE; |
| char bit; |
| |
| PERL_ARGS_ASSERT_GROK_BIN; |
| |
| if (!(*flags & PERL_SCAN_DISALLOW_PREFIX)) { |
| /* strip off leading b or 0b. |
| for compatibility silently suffer "b" and "0b" as valid binary |
| numbers. */ |
| if (len >= 1) { |
| if (s[0] == 'b' || s[0] == 'B') { |
| s++; |
| len--; |
| } |
| else if (len >= 2 && s[0] == '0' && (s[1] == 'b' || s[1] == 'B')) { |
| s+=2; |
| len-=2; |
| } |
| } |
| } |
| |
| for (; len-- && (bit = *s); s++) { |
| if (bit == '0' || bit == '1') { |
| /* Write it in this wonky order with a goto to attempt to get the |
| compiler to make the common case integer-only loop pretty tight. |
| With gcc seems to be much straighter code than old scan_bin. */ |
| redo: |
| if (!overflowed) { |
| if (value <= max_div_2) { |
| value = (value << 1) | (bit - '0'); |
| continue; |
| } |
| /* Bah. We're just overflowed. */ |
| /* diag_listed_as: Integer overflow in %s number */ |
| Perl_ck_warner_d(aTHX_ packWARN(WARN_OVERFLOW), |
| "Integer overflow in binary number"); |
| overflowed = TRUE; |
| value_nv = (NV) value; |
| } |
| value_nv *= 2.0; |
| /* If an NV has not enough bits in its mantissa to |
| * represent a UV this summing of small low-order numbers |
| * is a waste of time (because the NV cannot preserve |
| * the low-order bits anyway): we could just remember when |
| * did we overflow and in the end just multiply value_nv by the |
| * right amount. */ |
| value_nv += (NV)(bit - '0'); |
| continue; |
| } |
| if (bit == '_' && len && allow_underscores && (bit = s[1]) |
| && (bit == '0' || bit == '1')) |
| { |
| --len; |
| ++s; |
| goto redo; |
| } |
| if (!(*flags & PERL_SCAN_SILENT_ILLDIGIT)) |
| Perl_ck_warner(aTHX_ packWARN(WARN_DIGIT), |
| "Illegal binary digit '%c' ignored", *s); |
| break; |
| } |
| |
| if ( ( overflowed && value_nv > 4294967295.0) |
| #if UVSIZE > 4 |
| || (!overflowed && value > 0xffffffff |
| && ! (*flags & PERL_SCAN_SILENT_NON_PORTABLE)) |
| #endif |
| ) { |
| Perl_ck_warner(aTHX_ packWARN(WARN_PORTABLE), |
| "Binary number > 0b11111111111111111111111111111111 non-portable"); |
| } |
| *len_p = s - start; |
| if (!overflowed) { |
| *flags = 0; |
| return value; |
| } |
| *flags = PERL_SCAN_GREATER_THAN_UV_MAX; |
| if (result) |
| *result = value_nv; |
| return UV_MAX; |
| } |
| |
| /* |
| =for apidoc grok_hex |
| |
| converts a string representing a hex number to numeric form. |
| |
| On entry I<start> and I<*len> give the string to scan, I<*flags> gives |
| conversion flags, and I<result> should be NULL or a pointer to an NV. |
| The scan stops at the end of the string, or the first invalid character. |
| Unless C<PERL_SCAN_SILENT_ILLDIGIT> is set in I<*flags>, encountering an |
| invalid character will also trigger a warning. |
| On return I<*len> is set to the length of the scanned string, |
| and I<*flags> gives output flags. |
| |
| If the value is <= UV_MAX it is returned as a UV, the output flags are clear, |
| and nothing is written to I<*result>. If the value is > UV_MAX C<grok_hex> |
| returns UV_MAX, sets C<PERL_SCAN_GREATER_THAN_UV_MAX> in the output flags, |
| and writes the value to I<*result> (or the value is discarded if I<result> |
| is NULL). |
| |
| The hex number may optionally be prefixed with "0x" or "x" unless |
| C<PERL_SCAN_DISALLOW_PREFIX> is set in I<*flags> on entry. If |
| C<PERL_SCAN_ALLOW_UNDERSCORES> is set in I<*flags> then the hex |
| number may use '_' characters to separate digits. |
| |
| =cut |
| |
| Not documented yet because experimental is C<PERL_SCAN_SILENT_NON_PORTABLE |
| which suppresses any message for non-portable numbers that are still valid |
| on this platform. |
| */ |
| |
| UV |
| Perl_grok_hex(pTHX_ const char *start, STRLEN *len_p, I32 *flags, NV *result) |
| { |
| dVAR; |
| const char *s = start; |
| STRLEN len = *len_p; |
| UV value = 0; |
| NV value_nv = 0; |
| const UV max_div_16 = UV_MAX / 16; |
| const bool allow_underscores = cBOOL(*flags & PERL_SCAN_ALLOW_UNDERSCORES); |
| bool overflowed = FALSE; |
| |
| PERL_ARGS_ASSERT_GROK_HEX; |
| |
| if (!(*flags & PERL_SCAN_DISALLOW_PREFIX)) { |
| /* strip off leading x or 0x. |
| for compatibility silently suffer "x" and "0x" as valid hex numbers. |
| */ |
| if (len >= 1) { |
| if (s[0] == 'x' || s[0] == 'X') { |
| s++; |
| len--; |
| } |
| else if (len >= 2 && s[0] == '0' && (s[1] == 'x' || s[1] == 'X')) { |
| s+=2; |
| len-=2; |
| } |
| } |
| } |
| |
| for (; len-- && *s; s++) { |
| const char *hexdigit = strchr(PL_hexdigit, *s); |
| if (hexdigit) { |
| /* Write it in this wonky order with a goto to attempt to get the |
| compiler to make the common case integer-only loop pretty tight. |
| With gcc seems to be much straighter code than old scan_hex. */ |
| redo: |
| if (!overflowed) { |
| if (value <= max_div_16) { |
| value = (value << 4) | ((hexdigit - PL_hexdigit) & 15); |
| continue; |
| } |
| /* Bah. We're just overflowed. */ |
| /* diag_listed_as: Integer overflow in %s number */ |
| Perl_ck_warner_d(aTHX_ packWARN(WARN_OVERFLOW), |
| "Integer overflow in hexadecimal number"); |
| overflowed = TRUE; |
| value_nv = (NV) value; |
| } |
| value_nv *= 16.0; |
| /* If an NV has not enough bits in its mantissa to |
| * represent a UV this summing of small low-order numbers |
| * is a waste of time (because the NV cannot preserve |
| * the low-order bits anyway): we could just remember when |
| * did we overflow and in the end just multiply value_nv by the |
| * right amount of 16-tuples. */ |
| value_nv += (NV)((hexdigit - PL_hexdigit) & 15); |
| continue; |
| } |
| if (*s == '_' && len && allow_underscores && s[1] |
| && (hexdigit = strchr(PL_hexdigit, s[1]))) |
| { |
| --len; |
| ++s; |
| goto redo; |
| } |
| if (!(*flags & PERL_SCAN_SILENT_ILLDIGIT)) |
| Perl_ck_warner(aTHX_ packWARN(WARN_DIGIT), |
| "Illegal hexadecimal digit '%c' ignored", *s); |
| break; |
| } |
| |
| if ( ( overflowed && value_nv > 4294967295.0) |
| #if UVSIZE > 4 |
| || (!overflowed && value > 0xffffffff |
| && ! (*flags & PERL_SCAN_SILENT_NON_PORTABLE)) |
| #endif |
| ) { |
| Perl_ck_warner(aTHX_ packWARN(WARN_PORTABLE), |
| "Hexadecimal number > 0xffffffff non-portable"); |
| } |
| *len_p = s - start; |
| if (!overflowed) { |
| *flags = 0; |
| return value; |
| } |
| *flags = PERL_SCAN_GREATER_THAN_UV_MAX; |
| if (result) |
| *result = value_nv; |
| return UV_MAX; |
| } |
| |
| /* |
| =for apidoc grok_oct |
| |
| converts a string representing an octal number to numeric form. |
| |
| On entry I<start> and I<*len> give the string to scan, I<*flags> gives |
| conversion flags, and I<result> should be NULL or a pointer to an NV. |
| The scan stops at the end of the string, or the first invalid character. |
| Unless C<PERL_SCAN_SILENT_ILLDIGIT> is set in I<*flags>, encountering an |
| 8 or 9 will also trigger a warning. |
| On return I<*len> is set to the length of the scanned string, |
| and I<*flags> gives output flags. |
| |
| If the value is <= UV_MAX it is returned as a UV, the output flags are clear, |
| and nothing is written to I<*result>. If the value is > UV_MAX C<grok_oct> |
| returns UV_MAX, sets C<PERL_SCAN_GREATER_THAN_UV_MAX> in the output flags, |
| and writes the value to I<*result> (or the value is discarded if I<result> |
| is NULL). |
| |
| If C<PERL_SCAN_ALLOW_UNDERSCORES> is set in I<*flags> then the octal |
| number may use '_' characters to separate digits. |
| |
| =cut |
| |
| Not documented yet because experimental is C<PERL_SCAN_SILENT_NON_PORTABLE |
| which suppresses any message for non-portable numbers that are still valid |
| on this platform. |
| */ |
| |
| UV |
| Perl_grok_oct(pTHX_ const char *start, STRLEN *len_p, I32 *flags, NV *result) |
| { |
| const char *s = start; |
| STRLEN len = *len_p; |
| UV value = 0; |
| NV value_nv = 0; |
| const UV max_div_8 = UV_MAX / 8; |
| const bool allow_underscores = cBOOL(*flags & PERL_SCAN_ALLOW_UNDERSCORES); |
| bool overflowed = FALSE; |
| |
| PERL_ARGS_ASSERT_GROK_OCT; |
| |
| for (; len-- && *s; s++) { |
| /* gcc 2.95 optimiser not smart enough to figure that this subtraction |
| out front allows slicker code. */ |
| int digit = *s - '0'; |
| if (digit >= 0 && digit <= 7) { |
| /* Write it in this wonky order with a goto to attempt to get the |
| compiler to make the common case integer-only loop pretty tight. |
| */ |
| redo: |
| if (!overflowed) { |
| if (value <= max_div_8) { |
| value = (value << 3) | digit; |
| continue; |
| } |
| /* Bah. We're just overflowed. */ |
| /* diag_listed_as: Integer overflow in %s number */ |
| Perl_ck_warner_d(aTHX_ packWARN(WARN_OVERFLOW), |
| "Integer overflow in octal number"); |
| overflowed = TRUE; |
| value_nv = (NV) value; |
| } |
| value_nv *= 8.0; |
| /* If an NV has not enough bits in its mantissa to |
| * represent a UV this summing of small low-order numbers |
| * is a waste of time (because the NV cannot preserve |
| * the low-order bits anyway): we could just remember when |
| * did we overflow and in the end just multiply value_nv by the |
| * right amount of 8-tuples. */ |
| value_nv += (NV)digit; |
| continue; |
| } |
| if (digit == ('_' - '0') && len && allow_underscores |
| && (digit = s[1] - '0') && (digit >= 0 && digit <= 7)) |
| { |
| --len; |
| ++s; |
| goto redo; |
| } |
| /* Allow \octal to work the DWIM way (that is, stop scanning |
| * as soon as non-octal characters are seen, complain only if |
| * someone seems to want to use the digits eight and nine). */ |
| if (digit == 8 || digit == 9) { |
| if (!(*flags & PERL_SCAN_SILENT_ILLDIGIT)) |
| Perl_ck_warner(aTHX_ packWARN(WARN_DIGIT), |
| "Illegal octal digit '%c' ignored", *s); |
| } |
| break; |
| } |
| |
| if ( ( overflowed && value_nv > 4294967295.0) |
| #if UVSIZE > 4 |
| || (!overflowed && value > 0xffffffff |
| && ! (*flags & PERL_SCAN_SILENT_NON_PORTABLE)) |
| #endif |
| ) { |
| Perl_ck_warner(aTHX_ packWARN(WARN_PORTABLE), |
| "Octal number > 037777777777 non-portable"); |
| } |
| *len_p = s - start; |
| if (!overflowed) { |
| *flags = 0; |
| return value; |
| } |
| *flags = PERL_SCAN_GREATER_THAN_UV_MAX; |
| if (result) |
| *result = value_nv; |
| return UV_MAX; |
| } |
| |
| /* |
| =for apidoc scan_bin |
| |
| For backwards compatibility. Use C<grok_bin> instead. |
| |
| =for apidoc scan_hex |
| |
| For backwards compatibility. Use C<grok_hex> instead. |
| |
| =for apidoc scan_oct |
| |
| For backwards compatibility. Use C<grok_oct> instead. |
| |
| =cut |
| */ |
| |
| NV |
| Perl_scan_bin(pTHX_ const char *start, STRLEN len, STRLEN *retlen) |
| { |
| NV rnv; |
| I32 flags = *retlen ? PERL_SCAN_ALLOW_UNDERSCORES : 0; |
| const UV ruv = grok_bin (start, &len, &flags, &rnv); |
| |
| PERL_ARGS_ASSERT_SCAN_BIN; |
| |
| *retlen = len; |
| return (flags & PERL_SCAN_GREATER_THAN_UV_MAX) ? rnv : (NV)ruv; |
| } |
| |
| NV |
| Perl_scan_oct(pTHX_ const char *start, STRLEN len, STRLEN *retlen) |
| { |
| NV rnv; |
| I32 flags = *retlen ? PERL_SCAN_ALLOW_UNDERSCORES : 0; |
| const UV ruv = grok_oct (start, &len, &flags, &rnv); |
| |
| PERL_ARGS_ASSERT_SCAN_OCT; |
| |
| *retlen = len; |
| return (flags & PERL_SCAN_GREATER_THAN_UV_MAX) ? rnv : (NV)ruv; |
| } |
| |
| NV |
| Perl_scan_hex(pTHX_ const char *start, STRLEN len, STRLEN *retlen) |
| { |
| NV rnv; |
| I32 flags = *retlen ? PERL_SCAN_ALLOW_UNDERSCORES : 0; |
| const UV ruv = grok_hex (start, &len, &flags, &rnv); |
| |
| PERL_ARGS_ASSERT_SCAN_HEX; |
| |
| *retlen = len; |
| return (flags & PERL_SCAN_GREATER_THAN_UV_MAX) ? rnv : (NV)ruv; |
| } |
| |
| /* |
| =for apidoc grok_numeric_radix |
| |
| Scan and skip for a numeric decimal separator (radix). |
| |
| =cut |
| */ |
| bool |
| Perl_grok_numeric_radix(pTHX_ const char **sp, const char *send) |
| { |
| #ifdef USE_LOCALE_NUMERIC |
| dVAR; |
| |
| PERL_ARGS_ASSERT_GROK_NUMERIC_RADIX; |
| |
| if (PL_numeric_radix_sv && IN_SOME_LOCALE_FORM) { |
| STRLEN len; |
| const char * const radix = SvPV(PL_numeric_radix_sv, len); |
| if (*sp + len <= send && memEQ(*sp, radix, len)) { |
| *sp += len; |
| return TRUE; |
| } |
| } |
| /* always try "." if numeric radix didn't match because |
| * we may have data from different locales mixed */ |
| #endif |
| |
| PERL_ARGS_ASSERT_GROK_NUMERIC_RADIX; |
| |
| if (*sp < send && **sp == '.') { |
| ++*sp; |
| return TRUE; |
| } |
| return FALSE; |
| } |
| |
| /* |
| =for apidoc grok_number |
| |
| Recognise (or not) a number. The type of the number is returned |
| (0 if unrecognised), otherwise it is a bit-ORed combination of |
| IS_NUMBER_IN_UV, IS_NUMBER_GREATER_THAN_UV_MAX, IS_NUMBER_NOT_INT, |
| IS_NUMBER_NEG, IS_NUMBER_INFINITY, IS_NUMBER_NAN (defined in perl.h). |
| |
| If the value of the number can fit an in UV, it is returned in the *valuep |
| IS_NUMBER_IN_UV will be set to indicate that *valuep is valid, IS_NUMBER_IN_UV |
| will never be set unless *valuep is valid, but *valuep may have been assigned |
| to during processing even though IS_NUMBER_IN_UV is not set on return. |
| If valuep is NULL, IS_NUMBER_IN_UV will be set for the same cases as when |
| valuep is non-NULL, but no actual assignment (or SEGV) will occur. |
| |
| IS_NUMBER_NOT_INT will be set with IS_NUMBER_IN_UV if trailing decimals were |
| seen (in which case *valuep gives the true value truncated to an integer), and |
| IS_NUMBER_NEG if the number is negative (in which case *valuep holds the |
| absolute value). IS_NUMBER_IN_UV is not set if e notation was used or the |
| number is larger than a UV. |
| |
| =cut |
| */ |
| int |
| Perl_grok_number(pTHX_ const char *pv, STRLEN len, UV *valuep) |
| { |
| const char *s = pv; |
| const char * const send = pv + len; |
| const UV max_div_10 = UV_MAX / 10; |
| const char max_mod_10 = UV_MAX % 10; |
| int numtype = 0; |
| int sawinf = 0; |
| int sawnan = 0; |
| |
| PERL_ARGS_ASSERT_GROK_NUMBER; |
| |
| while (s < send && isSPACE(*s)) |
| s++; |
| if (s == send) { |
| return 0; |
| } else if (*s == '-') { |
| s++; |
| numtype = IS_NUMBER_NEG; |
| } |
| else if (*s == '+') |
| s++; |
| |
| if (s == send) |
| return 0; |
| |
| /* next must be digit or the radix separator or beginning of infinity */ |
| if (isDIGIT(*s)) { |
| /* UVs are at least 32 bits, so the first 9 decimal digits cannot |
| overflow. */ |
| UV value = *s - '0'; |
| /* This construction seems to be more optimiser friendly. |
| (without it gcc does the isDIGIT test and the *s - '0' separately) |
| With it gcc on arm is managing 6 instructions (6 cycles) per digit. |
| In theory the optimiser could deduce how far to unroll the loop |
| before checking for overflow. */ |
| if (++s < send) { |
| int digit = *s - '0'; |
| if (digit >= 0 && digit <= 9) { |
| value = value * 10 + digit; |
| if (++s < send) { |
| digit = *s - '0'; |
| if (digit >= 0 && digit <= 9) { |
| value = value * 10 + digit; |
| if (++s < send) { |
| digit = *s - '0'; |
| if (digit >= 0 && digit <= 9) { |
| value = value * 10 + digit; |
| if (++s < send) { |
| digit = *s - '0'; |
| if (digit >= 0 && digit <= 9) { |
| value = value * 10 + digit; |
| if (++s < send) { |
| digit = *s - '0'; |
| if (digit >= 0 && digit <= 9) { |
| value = value * 10 + digit; |
| if (++s < send) { |
| digit = *s - '0'; |
| if (digit >= 0 && digit <= 9) { |
| value = value * 10 + digit; |
| if (++s < send) { |
| digit = *s - '0'; |
| if (digit >= 0 && digit <= 9) { |
| value = value * 10 + digit; |
| if (++s < send) { |
| digit = *s - '0'; |
| if (digit >= 0 && digit <= 9) { |
| value = value * 10 + digit; |
| if (++s < send) { |
| /* Now got 9 digits, so need to check |
| each time for overflow. */ |
| digit = *s - '0'; |
| while (digit >= 0 && digit <= 9 |
| && (value < max_div_10 |
| || (value == max_div_10 |
| && digit <= max_mod_10))) { |
| value = value * 10 + digit; |
| if (++s < send) |
| digit = *s - '0'; |
| else |
| break; |
| } |
| if (digit >= 0 && digit <= 9 |
| && (s < send)) { |
| /* value overflowed. |
| skip the remaining digits, don't |
| worry about setting *valuep. */ |
| do { |
| s++; |
| } while (s < send && isDIGIT(*s)); |
| numtype |= |
| IS_NUMBER_GREATER_THAN_UV_MAX; |
| goto skip_value; |
| } |
| } |
| } |
| } |
| } |
| } |
| } |
| } |
| } |
| } |
| } |
| } |
| } |
| } |
| } |
| } |
| } |
| } |
| numtype |= IS_NUMBER_IN_UV; |
| if (valuep) |
| *valuep = value; |
| |
| skip_value: |
| if (GROK_NUMERIC_RADIX(&s, send)) { |
| numtype |= IS_NUMBER_NOT_INT; |
| while (s < send && isDIGIT(*s)) /* optional digits after the radix */ |
| s++; |
| } |
| } |
| else if (GROK_NUMERIC_RADIX(&s, send)) { |
| numtype |= IS_NUMBER_NOT_INT | IS_NUMBER_IN_UV; /* valuep assigned below */ |
| /* no digits before the radix means we need digits after it */ |
| if (s < send && isDIGIT(*s)) { |
| do { |
| s++; |
| } while (s < send && isDIGIT(*s)); |
| if (valuep) { |
| /* integer approximation is valid - it's 0. */ |
| *valuep = 0; |
| } |
| } |
| else |
| return 0; |
| } else if (*s == 'I' || *s == 'i') { |
| s++; if (s == send || (*s != 'N' && *s != 'n')) return 0; |
| s++; if (s == send || (*s != 'F' && *s != 'f')) return 0; |
| s++; if (s < send && (*s == 'I' || *s == 'i')) { |
| s++; if (s == send || (*s != 'N' && *s != 'n')) return 0; |
| s++; if (s == send || (*s != 'I' && *s != 'i')) return 0; |
| s++; if (s == send || (*s != 'T' && *s != 't')) return 0; |
| s++; if (s == send || (*s != 'Y' && *s != 'y')) return 0; |
| s++; |
| } |
| sawinf = 1; |
| } else if (*s == 'N' || *s == 'n') { |
| /* XXX TODO: There are signaling NaNs and quiet NaNs. */ |
| s++; if (s == send || (*s != 'A' && *s != 'a')) return 0; |
| s++; if (s == send || (*s != 'N' && *s != 'n')) return 0; |
| s++; |
| sawnan = 1; |
| } else |
| return 0; |
| |
| if (sawinf) { |
| numtype &= IS_NUMBER_NEG; /* Keep track of sign */ |
| numtype |= IS_NUMBER_INFINITY | IS_NUMBER_NOT_INT; |
| } else if (sawnan) { |
| numtype &= IS_NUMBER_NEG; /* Keep track of sign */ |
| numtype |= IS_NUMBER_NAN | IS_NUMBER_NOT_INT; |
| } else if (s < send) { |
| /* we can have an optional exponent part */ |
| if (*s == 'e' || *s == 'E') { |
| /* The only flag we keep is sign. Blow away any "it's UV" */ |
| numtype &= IS_NUMBER_NEG; |
| numtype |= IS_NUMBER_NOT_INT; |
| s++; |
| if (s < send && (*s == '-' || *s == '+')) |
| s++; |
| if (s < send && isDIGIT(*s)) { |
| do { |
| s++; |
| } while (s < send && isDIGIT(*s)); |
| } |
| else |
| return 0; |
| } |
| } |
| while (s < send && isSPACE(*s)) |
| s++; |
| if (s >= send) |
| return numtype; |
| if (len == 10 && memEQ(pv, "0 but true", 10)) { |
| if (valuep) |
| *valuep = 0; |
| return IS_NUMBER_IN_UV; |
| } |
| return 0; |
| } |
| |
| STATIC NV |
| S_mulexp10(NV value, I32 exponent) |
| { |
| NV result = 1.0; |
| NV power = 10.0; |
| bool negative = 0; |
| I32 bit; |
| |
| if (exponent == 0) |
| return value; |
| if (value == 0) |
| return (NV)0; |
| |
| /* On OpenVMS VAX we by default use the D_FLOAT double format, |
| * and that format does not have *easy* capabilities [1] for |
| * overflowing doubles 'silently' as IEEE fp does. We also need |
| * to support G_FLOAT on both VAX and Alpha, and though the exponent |
| * range is much larger than D_FLOAT it still doesn't do silent |
| * overflow. Therefore we need to detect early whether we would |
| * overflow (this is the behaviour of the native string-to-float |
| * conversion routines, and therefore of native applications, too). |
| * |
| * [1] Trying to establish a condition handler to trap floating point |
| * exceptions is not a good idea. */ |
| |
| /* In UNICOS and in certain Cray models (such as T90) there is no |
| * IEEE fp, and no way at all from C to catch fp overflows gracefully. |
| * There is something you can do if you are willing to use some |
| * inline assembler: the instruction is called DFI-- but that will |
| * disable *all* floating point interrupts, a little bit too large |
| * a hammer. Therefore we need to catch potential overflows before |
| * it's too late. */ |
| |
| #if ((defined(VMS) && !defined(__IEEE_FP)) || defined(_UNICOS)) && defined(NV_MAX_10_EXP) |
| STMT_START { |
| const NV exp_v = log10(value); |
| if (exponent >= NV_MAX_10_EXP || exponent + exp_v >= NV_MAX_10_EXP) |
| return NV_MAX; |
| if (exponent < 0) { |
| if (-(exponent + exp_v) >= NV_MAX_10_EXP) |
| return 0.0; |
| while (-exponent >= NV_MAX_10_EXP) { |
| /* combination does not overflow, but 10^(-exponent) does */ |
| value /= 10; |
| ++exponent; |
| } |
| } |
| } STMT_END; |
| #endif |
| |
| if (exponent < 0) { |
| negative = 1; |
| exponent = -exponent; |
| } |
| for (bit = 1; exponent; bit <<= 1) { |
| if (exponent & bit) { |
| exponent ^= bit; |
| result *= power; |
| /* Floating point exceptions are supposed to be turned off, |
| * but if we're obviously done, don't risk another iteration. |
| */ |
| if (exponent == 0) break; |
| } |
| power *= power; |
| } |
| return negative ? value / result : value * result; |
| } |
| |
| NV |
| Perl_my_atof(pTHX_ const char* s) |
| { |
| NV x = 0.0; |
| #ifdef USE_LOCALE_NUMERIC |
| dVAR; |
| |
| PERL_ARGS_ASSERT_MY_ATOF; |
| |
| if (PL_numeric_local && IN_SOME_LOCALE_FORM) { |
| NV y; |
| |
| /* Scan the number twice; once using locale and once without; |
| * choose the larger result (in absolute value). */ |
| Perl_atof2(s, x); |
| SET_NUMERIC_STANDARD(); |
| Perl_atof2(s, y); |
| SET_NUMERIC_LOCAL(); |
| if ((y < 0.0 && y < x) || (y > 0.0 && y > x)) |
| return y; |
| } |
| else |
| Perl_atof2(s, x); |
| #else |
| Perl_atof2(s, x); |
| #endif |
| return x; |
| } |
| |
| char* |
| Perl_my_atof2(pTHX_ const char* orig, NV* value) |
| { |
| NV result[3] = {0.0, 0.0, 0.0}; |
| const char* s = orig; |
| #ifdef USE_PERL_ATOF |
| UV accumulator[2] = {0,0}; /* before/after dp */ |
| bool negative = 0; |
| const char* send = s + strlen(orig) - 1; |
| bool seen_digit = 0; |
| I32 exp_adjust[2] = {0,0}; |
| I32 exp_acc[2] = {-1, -1}; |
| /* the current exponent adjust for the accumulators */ |
| I32 exponent = 0; |
| I32 seen_dp = 0; |
| I32 digit = 0; |
| I32 old_digit = 0; |
| I32 sig_digits = 0; /* noof significant digits seen so far */ |
| |
| PERL_ARGS_ASSERT_MY_ATOF2; |
| |
| /* There is no point in processing more significant digits |
| * than the NV can hold. Note that NV_DIG is a lower-bound value, |
| * while we need an upper-bound value. We add 2 to account for this; |
| * since it will have been conservative on both the first and last digit. |
| * For example a 32-bit mantissa with an exponent of 4 would have |
| * exact values in the set |
| * 4 |
| * 8 |
| * .. |
| * 17179869172 |
| * 17179869176 |
| * 17179869180 |
| * |
| * where for the purposes of calculating NV_DIG we would have to discount |
| * both the first and last digit, since neither can hold all values from |
| * 0..9; but for calculating the value we must examine those two digits. |
| */ |
| #ifdef MAX_SIG_DIG_PLUS |
| /* It is not necessarily the case that adding 2 to NV_DIG gets all the |
| possible digits in a NV, especially if NVs are not IEEE compliant |
| (e.g., long doubles on IRIX) - Allen <allens@cpan.org> */ |
| # define MAX_SIG_DIGITS (NV_DIG+MAX_SIG_DIG_PLUS) |
| #else |
| # define MAX_SIG_DIGITS (NV_DIG+2) |
| #endif |
| |
| /* the max number we can accumulate in a UV, and still safely do 10*N+9 */ |
| #define MAX_ACCUMULATE ( (UV) ((UV_MAX - 9)/10)) |
| |
| /* leading whitespace */ |
| while (isSPACE(*s)) |
| ++s; |
| |
| /* sign */ |
| switch (*s) { |
| case '-': |
| negative = 1; |
| /* fall through */ |
| case '+': |
| ++s; |
| } |
| |
| /* punt to strtod for NaN/Inf; if no support for it there, tough luck */ |
| |
| #ifdef HAS_STRTOD |
| if (*s == 'n' || *s == 'N' || *s == 'i' || *s == 'I') { |
| const char *p = negative ? s - 1 : s; |
| char *endp; |
| NV rslt; |
| rslt = strtod(p, &endp); |
| if (endp != p) { |
| *value = rslt; |
| return (char *)endp; |
| } |
| } |
| #endif |
| |
| /* we accumulate digits into an integer; when this becomes too |
| * large, we add the total to NV and start again */ |
| |
| while (1) { |
| if (isDIGIT(*s)) { |
| seen_digit = 1; |
| old_digit = digit; |
| digit = *s++ - '0'; |
| if (seen_dp) |
| exp_adjust[1]++; |
| |
| /* don't start counting until we see the first significant |
| * digit, eg the 5 in 0.00005... */ |
| if (!sig_digits && digit == 0) |
| continue; |
| |
| if (++sig_digits > MAX_SIG_DIGITS) { |
| /* limits of precision reached */ |
| if (digit > 5) { |
| ++accumulator[seen_dp]; |
| } else if (digit == 5) { |
| if (old_digit % 2) { /* round to even - Allen */ |
| ++accumulator[seen_dp]; |
| } |
| } |
| if (seen_dp) { |
| exp_adjust[1]--; |
| } else { |
| exp_adjust[0]++; |
| } |
| /* skip remaining digits */ |
| while (isDIGIT(*s)) { |
| ++s; |
| if (! seen_dp) { |
| exp_adjust[0]++; |
| } |
| } |
| /* warn of loss of precision? */ |
| } |
| else { |
| if (accumulator[seen_dp] > MAX_ACCUMULATE) { |
| /* add accumulator to result and start again */ |
| result[seen_dp] = S_mulexp10(result[seen_dp], |
| exp_acc[seen_dp]) |
| + (NV)accumulator[seen_dp]; |
| accumulator[seen_dp] = 0; |
| exp_acc[seen_dp] = 0; |
| } |
| accumulator[seen_dp] = accumulator[seen_dp] * 10 + digit; |
| ++exp_acc[seen_dp]; |
| } |
| } |
| else if (!seen_dp && GROK_NUMERIC_RADIX(&s, send)) { |
| seen_dp = 1; |
| if (sig_digits > MAX_SIG_DIGITS) { |
| do { |
| ++s; |
| } while (isDIGIT(*s)); |
| break; |
| } |
| } |
| else { |
| break; |
| } |
| } |
| |
| result[0] = S_mulexp10(result[0], exp_acc[0]) + (NV)accumulator[0]; |
| if (seen_dp) { |
| result[1] = S_mulexp10(result[1], exp_acc[1]) + (NV)accumulator[1]; |
| } |
| |
| if (seen_digit && (*s == 'e' || *s == 'E')) { |
| bool expnegative = 0; |
| |
| ++s; |
| switch (*s) { |
| case '-': |
| expnegative = 1; |
| /* fall through */ |
| case '+': |
| ++s; |
| } |
| while (isDIGIT(*s)) |
| exponent = exponent * 10 + (*s++ - '0'); |
| if (expnegative) |
| exponent = -exponent; |
| } |
| |
| |
| |
| /* now apply the exponent */ |
| |
| if (seen_dp) { |
| result[2] = S_mulexp10(result[0],exponent+exp_adjust[0]) |
| + S_mulexp10(result[1],exponent-exp_adjust[1]); |
| } else { |
| result[2] = S_mulexp10(result[0],exponent+exp_adjust[0]); |
| } |
| |
| /* now apply the sign */ |
| if (negative) |
| result[2] = -result[2]; |
| #endif /* USE_PERL_ATOF */ |
| *value = result[2]; |
| return (char *)s; |
| } |
| |
| #if ! defined(HAS_MODFL) && defined(HAS_AINTL) && defined(HAS_COPYSIGNL) |
| long double |
| Perl_my_modfl(long double x, long double *ip) |
| { |
| *ip = aintl(x); |
| return (x == *ip ? copysignl(0.0L, x) : x - *ip); |
| } |
| #endif |
| |
| #if ! defined(HAS_FREXPL) && defined(HAS_ILOGBL) && defined(HAS_SCALBNL) |
| long double |
| Perl_my_frexpl(long double x, int *e) { |
| *e = x == 0.0L ? 0 : ilogbl(x) + 1; |
| return (scalbnl(x, -*e)); |
| } |
| #endif |
| |
| /* |
| =for apidoc Perl_signbit |
| |
| Return a non-zero integer if the sign bit on an NV is set, and 0 if |
| it is not. |
| |
| If Configure detects this system has a signbit() that will work with |
| our NVs, then we just use it via the #define in perl.h. Otherwise, |
| fall back on this implementation. As a first pass, this gets everything |
| right except -0.0. Alas, catching -0.0 is the main use for this function, |
| so this is not too helpful yet. Still, at least we have the scaffolding |
| in place to support other systems, should that prove useful. |
| |
| |
| Configure notes: This function is called 'Perl_signbit' instead of a |
| plain 'signbit' because it is easy to imagine a system having a signbit() |
| function or macro that doesn't happen to work with our particular choice |
| of NVs. We shouldn't just re-#define signbit as Perl_signbit and expect |
| the standard system headers to be happy. Also, this is a no-context |
| function (no pTHX_) because Perl_signbit() is usually re-#defined in |
| perl.h as a simple macro call to the system's signbit(). |
| Users should just always call Perl_signbit(). |
| |
| =cut |
| */ |
| #if !defined(HAS_SIGNBIT) |
| int |
| Perl_signbit(NV x) { |
| return (x < 0.0) ? 1 : 0; |
| } |
| #endif |
| |
| /* |
| * Local variables: |
| * c-indentation-style: bsd |
| * c-basic-offset: 4 |
| * indent-tabs-mode: t |
| * End: |
| * |
| * ex: set ts=8 sts=4 sw=4 noet: |
| */ |