X-Git-Url: https://perl5.git.perl.org/perl5.git/blobdiff_plain/02fd9d541c593812f3e152dc406cb4399353d5dc..d43c116b2ae74ec1f3ed78829d4f3ca76f091390:/numeric.c diff --git a/numeric.c b/numeric.c index 5d2fc5c..52c4547 100644 --- a/numeric.c +++ b/numeric.c @@ -16,9 +16,6 @@ */ /* -=head1 Numeric functions - -=cut This file contains all the stuff needed by perl for manipulating numeric values, including such things as replacements for the OS's atof() function @@ -90,14 +87,14 @@ It properly handles the locale radix character, meaning it expects a dot except when called from within the scope of S>, in which case the radix character should be that specified by the current locale. -The synonym Strod() may be used instead. +The synonym Strtod() may be used instead. =cut */ NV -my_strtod(const char * const s, char **e) +Perl_my_strtod(const char * const s, char **e) { dTHX; @@ -208,24 +205,31 @@ Perl_cast_uv(NV f) converts a string representing a binary number to numeric form. -On entry C and C<*len> give the string to scan, C<*flags> gives -conversion flags, and C should be C or a pointer to an NV. -The scan stops at the end of the string, or the first invalid character. -Unless C is set in C<*flags>, encountering an -invalid character will also trigger a warning. -On return C<*len> is set to the length of the scanned string, -and C<*flags> gives output flags. +On entry C and C<*len_p> give the string to scan, C<*flags> gives +conversion flags, and C should be C or a pointer to an NV. The +scan stops at the end of the string, or at just before the first invalid +character. Unless C is set in C<*flags>, +encountering an invalid character (except NUL) will also trigger a warning. On +return C<*len_p> is set to the length of the scanned string, and C<*flags> +gives output flags. If the value is <= C it is returned as a UV, the output flags are clear, and nothing is written to C<*result>. If the value is > C, C returns C, sets C in the output flags, -and writes the value to C<*result> (or the value is discarded if C -is NULL). +and writes an approximation of the correct value into C<*result> (which is an +NV; or the approximation is discarded if C is NULL). The binary number may optionally be prefixed with C<"0b"> or C<"b"> unless -C is set in C<*flags> on entry. If -C is set in C<*flags> then the binary -number may use C<"_"> characters to separate digits. +C is set in C<*flags> on entry. + +If C is set in C<*flags> then any or all pairs of +digits may be separated from each other by a single underscore; also a single +leading underscore is accepted. + +=for apidoc Amnh||PERL_SCAN_ALLOW_UNDERSCORES +=for apidoc Amnh||PERL_SCAN_DISALLOW_PREFIX +=for apidoc Amnh||PERL_SCAN_GREATER_THAN_UV_MAX +=for apidoc Amnh||PERL_SCAN_SILENT_ILLDIGIT =cut @@ -237,93 +241,9 @@ 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 (isALPHA_FOLD_EQ(s[0], 'b')) { - s++; - len--; - } - else if (len >= 2 && s[0] == '0' && (isALPHA_FOLD_EQ(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; + return grok_bin(start, len_p, flags, result); } /* @@ -332,119 +252,39 @@ Perl_grok_bin(pTHX_ const char *start, STRLEN *len_p, I32 *flags, NV *result) converts a string representing a hex number to numeric form. On entry C and C<*len_p> give the string to scan, C<*flags> gives -conversion flags, and C should be C or a pointer to an NV. -The scan stops at the end of the string, or the first invalid character. -Unless C is set in C<*flags>, encountering an -invalid character will also trigger a warning. -On return C<*len> is set to the length of the scanned string, -and C<*flags> gives output flags. +conversion flags, and C should be C or a pointer to an NV. The +scan stops at the end of the string, or at just before the first invalid +character. Unless C is set in C<*flags>, +encountering an invalid character (except NUL) will also trigger a warning. On +return C<*len_p> is set to the length of the scanned string, and C<*flags> +gives output flags. If the value is <= C it is returned as a UV, the output flags are clear, and nothing is written to C<*result>. If the value is > C, C returns C, sets C in the output flags, -and writes the value to C<*result> (or the value is discarded if C -is C). +and writes an approximation of the correct value into C<*result> (which is an +NV; or the approximation is discarded if C is NULL). The hex number may optionally be prefixed with C<"0x"> or C<"x"> unless -C is set in C<*flags> on entry. If -C is set in C<*flags> then the hex -number may use C<"_"> characters to separate digits. +C is set in C<*flags> on entry. + +If C is set in C<*flags> then any or all pairs of +digits may be separated from each other by a single underscore; also a single +leading underscore is accepted. =cut -Not documented yet because experimental is C which suppresses any message for non-portable numbers, but which are valid -on this platform. +on this platform. But, C<*flags> will have the corresponding flag bit set. */ UV Perl_grok_hex(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_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 (isALPHA_FOLD_EQ(s[0], 'x')) { - s++; - len--; - } - else if (len >= 2 && s[0] == '0' && (isALPHA_FOLD_EQ(s[1], 'x'))) { - s+=2; - len-=2; - } - } - } - - for (; len-- && *s; s++) { - if (isXDIGIT(*s)) { - /* 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) | XDIGIT_VALUE(*s); - 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) XDIGIT_VALUE(*s); - continue; - } - if (*s == '_' && len && allow_underscores && s[1] - && isXDIGIT(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; + return grok_hex(start, len_p, flags, result); } /* @@ -452,22 +292,26 @@ Perl_grok_hex(pTHX_ const char *start, STRLEN *len_p, I32 *flags, NV *result) converts a string representing an octal number to numeric form. -On entry C and C<*len> give the string to scan, C<*flags> gives -conversion flags, and C should be C or a pointer to an NV. -The scan stops at the end of the string, or the first invalid character. -Unless C is set in C<*flags>, encountering an -8 or 9 will also trigger a warning. -On return C<*len> is set to the length of the scanned string, -and C<*flags> gives output flags. +On entry C and C<*len_p> give the string to scan, C<*flags> gives +conversion flags, and C should be C or a pointer to an NV. The +scan stops at the end of the string, or at just before the first invalid +character. Unless C is set in C<*flags>, +encountering an invalid character (except NUL) will also trigger a warning. On +return C<*len_p> is set to the length of the scanned string, and C<*flags> +gives output flags. If the value is <= C it is returned as a UV, the output flags are clear, and nothing is written to C<*result>. If the value is > C, C returns C, sets C in the output flags, -and writes the value to C<*result> (or the value is discarded if C -is C). +and writes an approximation of the correct value into C<*result> (which is an +NV; or the approximation is discarded if C is NULL). + +If C is set in C<*flags> then any or all pairs of +digits may be separated from each other by a single underscore; also a single +leading underscore is accepted. -If C is set in C<*flags> then the octal -number may use C<"_"> characters to separate digits. +The C flag is always treated as being set for +this function. =cut @@ -479,76 +323,277 @@ on this platform. UV Perl_grok_oct(pTHX_ const char *start, STRLEN *len_p, I32 *flags, NV *result) { - const char *s = start; + PERL_ARGS_ASSERT_GROK_OCT; + + return grok_oct(start, len_p, flags, result); +} + +STATIC void +S_output_non_portable(pTHX_ const U8 base) +{ + /* Display the proper message for a number in the given input base not + * fitting in 32 bits */ + const char * which = (base == 2) + ? "Binary number > 0b11111111111111111111111111111111" + : (base == 8) + ? "Octal number > 037777777777" + : "Hexadecimal number > 0xffffffff"; + + PERL_ARGS_ASSERT_OUTPUT_NON_PORTABLE; + + /* Also there are listings for the other two. That's because, since they + * are the first word, it would be hard for a user to find them there + * starting with a %s */ + /* diag_listed_as: Hexadecimal number > 0xffffffff non-portable */ + Perl_ck_warner(aTHX_ packWARN(WARN_PORTABLE), "%s non-portable", which); +} + +UV +Perl_grok_bin_oct_hex(pTHX_ const char *start, + STRLEN *len_p, + I32 *flags, + NV *result, + const unsigned shift, /* 1 for binary; 3 for octal; + 4 for hex */ + const U8 class_bit, + const char prefix + ) + +{ + const char *s0 = start; + const char *s; STRLEN len = *len_p; + STRLEN bytes_so_far; /* How many real digits have been processed */ 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); + const PERL_UINT_FAST8_T base = 1 << shift; /* 2, 8, or 16 */ + const UV max_div= UV_MAX / base; /* Value above which, the next digit + processed would overflow */ + const I32 input_flags = *flags; + const bool allow_underscores = + cBOOL(input_flags & PERL_SCAN_ALLOW_UNDERSCORES); bool overflowed = FALSE; - PERL_ARGS_ASSERT_GROK_OCT; + /* In overflows, this keeps track of how much to multiply the overflowed NV + * by as we continue to parse the remaining digits */ + NV factor = 0; + + /* This function unifies the core of grok_bin, grok_oct, and grok_hex. It + * is optimized for hex conversion. For example, it uses XDIGIT_VALUE to + * find the numeric value of a digit. That requires more instructions than + * OCTAL_VALUE would, but gives the same result for the narrowed range of + * octal digits; same for binary. If it were ever critical to squeeze more + * performance from this, the function could become grok_hex, and a regen + * perl script could scan it and write out two edited copies for the other + * two functions. That would improve the performance of all three + * somewhat. Besides eliminating XDIGIT_VALUE for the other two, extra + * parameters are now passed to this to avoid conditionals. Those could + * become declared consts, like: + * const U8 base = 16; + * const U8 base = 8; + * ... + */ + + PERL_ARGS_ASSERT_GROK_BIN_OCT_HEX; + + ASSUME(inRANGE(shift, 1, 4) && shift != 2); + + /* Clear output flags; unlikely to find a problem that sets them */ + *flags = 0; + + if (!(input_flags & PERL_SCAN_DISALLOW_PREFIX)) { + + /* strip off leading b or 0b; x or 0x. + for compatibility silently suffer "b" and "0b" as valid binary; "x" + and "0x" as valid hex numbers. */ + if (len >= 1) { + if (isALPHA_FOLD_EQ(s0[0], prefix)) { + s0++; + len--; + } + else if (len >= 2 && s0[0] == '0' && (isALPHA_FOLD_EQ(s0[1], prefix))) { + s0+=2; + len-=2; + } + } + } + + s = s0; /* s0 potentially advanced from 'start' */ - for (; len-- && *s; s++) { - if (isOCTAL(*s)) { + /* Unroll the loop so that the first 8 digits are branchless except for the + * switch. A ninth hex one overflows a 32 bit word. */ + switch (len) { + case 0: + return 0; + default: + if (UNLIKELY(! _generic_isCC(*s, class_bit))) break; + value = (value << shift) | XDIGIT_VALUE(*s); + s++; + /* FALLTHROUGH */ + case 7: + if (UNLIKELY(! _generic_isCC(*s, class_bit))) break; + value = (value << shift) | XDIGIT_VALUE(*s); + s++; + /* FALLTHROUGH */ + case 6: + if (UNLIKELY(! _generic_isCC(*s, class_bit))) break; + value = (value << shift) | XDIGIT_VALUE(*s); + s++; + /* FALLTHROUGH */ + case 5: + if (UNLIKELY(! _generic_isCC(*s, class_bit))) break; + value = (value << shift) | XDIGIT_VALUE(*s); + s++; + /* FALLTHROUGH */ + case 4: + if (UNLIKELY(! _generic_isCC(*s, class_bit))) break; + value = (value << shift) | XDIGIT_VALUE(*s); + s++; + /* FALLTHROUGH */ + case 3: + if (UNLIKELY(! _generic_isCC(*s, class_bit))) break; + value = (value << shift) | XDIGIT_VALUE(*s); + s++; + /* FALLTHROUGH */ + case 2: + if (UNLIKELY(! _generic_isCC(*s, class_bit))) break; + value = (value << shift) | XDIGIT_VALUE(*s); + s++; + /* FALLTHROUGH */ + case 1: + if (UNLIKELY(! _generic_isCC(*s, class_bit))) break; + value = (value << shift) | XDIGIT_VALUE(*s); + + if (LIKELY(len <= 8)) { + return value; + } + + s++; + break; + } + + bytes_so_far = s - s0; + factor = shift << bytes_so_far; + len -= bytes_so_far; + + for (; len--; s++) { + if (_generic_isCC(*s, class_bit)) { /* 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. + (khw suspects that adding a LIKELY() just above would do the + same thing) */ redo: - if (!overflowed) { - if (value <= max_div_8) { - value = (value << 3) | OCTAL_VALUE(*s); - 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"); + if (LIKELY(value <= max_div)) { + value = (value << shift) | XDIGIT_VALUE(*s); + /* Note XDIGIT_VALUE() is branchless, works on binary + * and octal as well, so can be used here, without + * slowing those down */ + factor *= 1 << shift; + continue; + } + + /* Bah. We are about to overflow. Instead, add the unoverflowed + * value to an NV that contains an approximation to the correct + * value. Each time through the loop we have increased 'factor' so + * that it gives how much the current approximation needs to + * effectively be shifted to make room for this new value */ + value_nv *= factor; + value_nv += (NV) value; + + /* Then we keep accumulating digits, until all are parsed. We + * start over using the current input value. This will be added to + * 'value_nv' eventually, either when all digits are gone, or we + * have overflowed this fresh start. */ + value = XDIGIT_VALUE(*s); + factor = 1 << shift; + + if (! overflowed) { overflowed = TRUE; - value_nv = (NV) value; + if ( ! (input_flags & PERL_SCAN_SILENT_OVERFLOW) + && ckWARN_d(WARN_OVERFLOW)) + { + Perl_warner(aTHX_ packWARN(WARN_OVERFLOW), + "Integer overflow in %s number", + (base == 16) ? "hexadecimal" + : (base == 2) + ? "binary" + : "octal"); + } } - 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) OCTAL_VALUE(*s); continue; } - if (*s == '_' && len && allow_underscores && isOCTAL(s[1])) { + + if ( *s == '_' + && len + && allow_underscores + && _generic_isCC(s[1], class_bit) + + /* Don't allow a leading underscore if the only-medial bit is + * set */ + && ( LIKELY(s > s0) + || UNLIKELY((input_flags & PERL_SCAN_ALLOW_MEDIAL_UNDERSCORES) + != PERL_SCAN_ALLOW_MEDIAL_UNDERSCORES))) + { --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. Since we - * know it is not octal, then if isDIGIT, must be an 8 or 9). */ - if (isDIGIT(*s)) { - if (!(*flags & PERL_SCAN_SILENT_ILLDIGIT)) - Perl_ck_warner(aTHX_ packWARN(WARN_DIGIT), - "Illegal octal digit '%c' ignored", *s); + + if (*s) { + if ( ! (input_flags & PERL_SCAN_SILENT_ILLDIGIT) + && ckWARN(WARN_DIGIT)) + { + if (base != 8) { + Perl_warner(aTHX_ packWARN(WARN_DIGIT), + "Illegal %s digit '%c' ignored", + ((base == 2) + ? "binary" + : "hexadecimal"), + *s); + } + else if (isDIGIT(*s)) { /* octal base */ + + /* 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. Since we know it is not octal, then if + * isDIGIT, must be an 8 or 9). */ + Perl_warner(aTHX_ packWARN(WARN_DIGIT), + "Illegal octal digit '%c' ignored", *s); + } + } + + if (input_flags & PERL_SCAN_NOTIFY_ILLDIGIT) { + *flags |= PERL_SCAN_NOTIFY_ILLDIGIT; + } } + break; } - if ( ( overflowed && value_nv > 4294967295.0) + *len_p = s - start; + + if (LIKELY(! overflowed)) { #if UVSIZE > 4 - || (!overflowed && value > 0xffffffff - && ! (*flags & PERL_SCAN_SILENT_NON_PORTABLE)) + if ( UNLIKELY(value > 0xffffffff) + && ! (input_flags & PERL_SCAN_SILENT_NON_PORTABLE)) + { + output_non_portable(base); + *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; + + /* Overflowed: Calculate the final overflow approximation */ + value_nv *= factor; + value_nv += (NV) value; + + output_non_portable(base); + + *flags |= PERL_SCAN_GREATER_THAN_UV_MAX + | PERL_SCAN_SILENT_NON_PORTABLE; if (result) *result = value_nv; return UV_MAX; @@ -678,6 +723,13 @@ If an infinity or a not-a-number is recognized, C<*sp> will point to one byte past the end of the recognized string. If the recognition fails, zero is returned, and C<*sp> will not move. +=for apidoc Amnh|bool|IS_NUMBER_GREATER_THAN_UV_MAX +=for apidoc Amnh|bool|IS_NUMBER_INFINITY +=for apidoc Amnh|bool|IS_NUMBER_IN_UV +=for apidoc Amnh|bool|IS_NUMBER_NAN +=for apidoc Amnh|bool|IS_NUMBER_NEG +=for apidoc Amnh|bool|IS_NUMBER_NOT_INT + =cut */ @@ -729,7 +781,7 @@ Perl_grok_infnan(pTHX_ const char** sp, const char* send) s++; if (s == send || isALPHA_FOLD_NE(*s, 'Y')) return fail; s++; } else if (odh) { - while (*s == '0') { /* 1.#INF00 */ + while (s < send && *s == '0') { /* 1.#INF00 */ s++; } } @@ -743,10 +795,10 @@ Perl_grok_infnan(pTHX_ const char** sp, const char* send) else if (isALPHA_FOLD_EQ(*s, 'D') && odh) { /* 1.#IND */ s++; flags |= IS_NUMBER_NAN | IS_NUMBER_NOT_INT; - while (*s == '0') { /* 1.#IND00 */ + while (s < send && *s == '0') { /* 1.#IND00 */ s++; } - if (*s) { + if (s < send && *s) { flags |= IS_NUMBER_TRAILING; } } else @@ -767,6 +819,9 @@ Perl_grok_infnan(pTHX_ const char** sp, const char* send) s++; flags |= IS_NUMBER_NAN | IS_NUMBER_NOT_INT; + if (s == send) { + return flags; + } /* NaN can be followed by various stuff (NaNQ, NaNS), but * there are also multiple different NaN values, and some @@ -778,6 +833,9 @@ Perl_grok_infnan(pTHX_ const char** sp, const char* send) /* "nanq" or "nans" are ok, though generating * these portably is tricky. */ s++; + if (s == send) { + return flags; + } } if (*s == '(') { /* C99 style "nan(123)" or Perlish equivalent "nan($uv)". */ @@ -943,6 +1001,8 @@ C allows only C, which allows for trailing non-numeric text on an otherwise successful I, setting C on the result. +=for apidoc Amnh||PERL_SCAN_TRAILING + =for apidoc grok_number Identical to C with C set to zero. @@ -970,109 +1030,153 @@ Perl_grok_number_flags(pTHX_ const char *pv, STRLEN len, UV *valuep, U32 flags) PERL_ARGS_ASSERT_GROK_NUMBER_FLAGS; - while (s < send && isSPACE(*s)) - s++; - if (s == send) { - return 0; - } else if (*s == '-') { - s++; - numtype = IS_NUMBER_NEG; + if (UNLIKELY(isSPACE(*s))) { + s++; + while (s < send) { + if (LIKELY(! isSPACE(*s))) goto non_space; + s++; + } + return 0; + non_space: ; } - else if (*s == '+') - s++; - if (s == send) - return 0; + /* See if signed. This assumes it is more likely to be unsigned, so + * penalizes signed by an extra conditional; rewarding unsigned by one fewer + * (because we detect '+' and '-' with a single test and then add a + * conditional to determine which) */ + if (UNLIKELY((*s & ~('+' ^ '-')) == ('+' & '-') )) { + + /* Here, on ASCII platforms, *s is one of: 0x29 = ')', 2B = '+', 2D = '-', + * 2F = '/'. That is, it is either a sign, or a character that doesn't + * belong in a number at all (unless it's a radix character in a weird + * locale). Given this, it's far more likely to be a minus than the + * others. (On EBCDIC it is one of 42, 44, 46, 48, 4A, 4C, 4E, (not 40 + * because can't be a space) 60, 62, 64, 66, 68, 6A, 6C, 6E. Again, + * only potentially a weird radix character, or 4E='+', or 60='-') */ + if (LIKELY(*s == '-')) { + s++; + numtype = IS_NUMBER_NEG; + } + else if (LIKELY(*s == '+')) + s++; + else /* Can't just return failure here, as it could be a weird radix + character */ + goto done_sign; + + if (UNLIKELY(s == send)) + return 0; + done_sign: ; + } /* The first digit (after optional sign): note that might * also point to "infinity" or "nan", or "1.#INF". */ d = s; /* next must be digit or the radix separator or beginning of infinity/nan */ - if (isDIGIT(*s)) { + if (LIKELY(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 (inRANGE(digit, 0, 9)) { + UV value = *s - '0'; /* Process this first (perhaps only) digit */ + int digit; + + s++; + + switch(send - s) { + default: /* 8 or more remaining characters */ + digit = *s - '0'; + if (UNLIKELY(! inRANGE(digit, 0, 9))) break; + value = value * 10 + digit; + s++; + /* FALLTHROUGH */ + case 7: + digit = *s - '0'; + if (UNLIKELY(! inRANGE(digit, 0, 9))) break; + value = value * 10 + digit; + s++; + /* FALLTHROUGH */ + case 6: + digit = *s - '0'; + if (UNLIKELY(! inRANGE(digit, 0, 9))) break; value = value * 10 + digit; - if (++s < send) { - digit = *s - '0'; - if (inRANGE(digit, 0, 9)) { - value = value * 10 + digit; - if (++s < send) { - digit = *s - '0'; - if (inRANGE(digit, 0, 9)) { + s++; + /* FALLTHROUGH */ + case 5: + digit = *s - '0'; + if (UNLIKELY(! inRANGE(digit, 0, 9))) break; + value = value * 10 + digit; + s++; + /* FALLTHROUGH */ + case 4: + digit = *s - '0'; + if (UNLIKELY(! inRANGE(digit, 0, 9))) break; + value = value * 10 + digit; + s++; + /* FALLTHROUGH */ + case 3: + digit = *s - '0'; + if (UNLIKELY(! inRANGE(digit, 0, 9))) break; + value = value * 10 + digit; + s++; + /* FALLTHROUGH */ + case 2: + digit = *s - '0'; + if (UNLIKELY(! inRANGE(digit, 0, 9))) break; + value = value * 10 + digit; + s++; + /* FALLTHROUGH */ + case 1: + digit = *s - '0'; + if (UNLIKELY(! inRANGE(digit, 0, 9))) break; + value = value * 10 + digit; + s++; + /* FALLTHROUGH */ + case 0: /* This case means the string consists of just the one + digit we already have processed */ + + /* If we got here by falling through other than the default: case, we + * have processed the whole string, and know it consists entirely of + * digits, and can't have overflowed. */ + if (s >= send) { + if (valuep) + *valuep = value; + return numtype|IS_NUMBER_IN_UV; + } + + /* Here, there are extra characters beyond the first 9 digits. Use a + * loop to accumulate any remaining digits, until we get a non-digit or + * would overflow. Note that leading zeros could cause us to get here + * without being close to overflowing. + * + * (The conditional 's >= send' above could be eliminated by making the + * default: in the switch to instead be 'case 8:', and process longer + * strings separately by using the loop below. This would penalize + * these inputs by the extra instructions needed for looping. That + * could be eliminated by copying the unwound code from above to handle + * the firt 9 digits of these. khw didn't think this saving of a + * single conditional was worth it.) */ + do { + digit = *s - '0'; + if (! inRANGE(digit, 0, 9)) goto mantissa_done; + if ( value < uv_max_div_10 + || ( value == uv_max_div_10 + && digit <= uv_max_mod_10)) + { value = value * 10 + digit; - if (++s < send) { - digit = *s - '0'; - if (inRANGE(digit, 0, 9)) { - value = value * 10 + digit; - if (++s < send) { - digit = *s - '0'; - if (inRANGE(digit, 0, 9)) { - value = value * 10 + digit; - if (++s < send) { - digit = *s - '0'; - if (inRANGE(digit, 0, 9)) { - value = value * 10 + digit; - if (++s < send) { - digit = *s - '0'; - if (inRANGE(digit, 0, 9)) { - value = value * 10 + digit; - if (++s < send) { - digit = *s - '0'; - if (inRANGE(digit, 0, 9)) { - value = value * 10 + digit; - if (++s < send) { - /* Now got 9 digits, so need to check - each time for overflow. */ - digit = *s - '0'; - while ( inRANGE(digit, 0, 9) - && (value < uv_max_div_10 - || (value == uv_max_div_10 - && digit <= uv_max_mod_10))) { - value = value * 10 + digit; - if (++s < send) - digit = *s - '0'; - else - break; - } - if (inRANGE(digit, 0, 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; - } - } - } - } - } - } - } - } - } - } - } - } - } + s++; } - } - } - } - } + else { /* value would overflow. 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; + } + } while (s < send); + } /* End switch on input length */ + + mantissa_done: numtype |= IS_NUMBER_IN_UV; if (valuep) *valuep = value; @@ -1083,7 +1187,7 @@ Perl_grok_number_flags(pTHX_ const char *pv, STRLEN len, UV *valuep, U32 flags) while (s < send && isDIGIT(*s)) /* optional digits after the radix */ s++; } - } + } /* End of *s is a digit */ 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 */ @@ -1100,9 +1204,9 @@ Perl_grok_number_flags(pTHX_ const char *pv, STRLEN len, UV *valuep, U32 flags) return 0; } - if (s > d && s < send) { + if (LIKELY(s > d) && s < send) { /* we can have an optional exponent part */ - if (isALPHA_FOLD_EQ(*s, 'e')) { + if (UNLIKELY(isALPHA_FOLD_EQ(*s, 'e'))) { s++; if (s < send && (*s == '-' || *s == '+')) s++; @@ -1121,17 +1225,23 @@ Perl_grok_number_flags(pTHX_ const char *pv, STRLEN len, UV *valuep, U32 flags) numtype |= IS_NUMBER_NOT_INT; } } - while (s < send && isSPACE(*s)) + + while (s < send) { + if (LIKELY(! isSPACE(*s))) goto end_space; s++; - if (s >= send) - return numtype; - if (memEQs(pv, len, "0 but true")) { + } + return numtype; + + end_space: + + if (UNLIKELY(memEQs(pv, len, "0 but true"))) { if (valuep) *valuep = 0; return IS_NUMBER_IN_UV; } + /* We could be e.g. at "Inf" or "NaN", or at the "#" of "1.#INF". */ - if ((s + 2 < send) && strchr("inqs#", toFOLD(*s))) { + if ((s + 2 < send) && UNLIKELY(memCHRs("inqs#", toFOLD(*s)))) { /* Really detect inf/nan. Start at d, not s, since the above * code might have already consumed the "1." or "1". */ const int infnan = Perl_grok_infnan(aTHX_ &d, send); @@ -1168,7 +1278,8 @@ If you constrain the portion of C that is looked at by this function (by passing a non-NULL C), and if the intial bytes of that portion form a valid value, it will return TRUE, setting C<*endptr> to the byte following the final digit of the value. But if there is no constraint at what's looked at, -all of C must be valid in order for TRUE to be returned. +all of C must be valid in order for TRUE to be returned. C<*endptr> is +unchanged from its value on input if FALSE is returned; The only characters this accepts are the decimal digits '0'..'9'. @@ -1353,7 +1464,18 @@ S_mulexp10(NV value, I32 exponent) NV Perl_my_atof(pTHX_ const char* s) { - /* 's' must be NUL terminated */ + +/* +=for apidoc my_atof + +L(3)>, but properly works with Perl locale handling, accepting a dot +radix character always, but also the current locale's radix character if and +only if called from within the lexical scope of a Perl C statement. + +N.B. C must be NUL terminated. + +=cut +*/ NV x = 0.0; @@ -1408,10 +1530,6 @@ Perl_my_atof(pTHX_ const char* s) #if defined(NV_INF) || defined(NV_NAN) -#ifdef USING_MSVC6 -# pragma warning(push) -# pragma warning(disable:4756;disable:4056) -#endif static char* S_my_atof_infnan(pTHX_ const char* s, bool negative, const char* send, NV* value) { @@ -1489,9 +1607,6 @@ S_my_atof_infnan(pTHX_ const char* s, bool negative, const char* send, NV* value } return NULL; } -#ifdef USING_MSVC6 -# pragma warning(pop) -#endif #endif /* if defined(NV_INF) || defined(NV_NAN) */ @@ -1551,6 +1666,15 @@ Perl_my_atof3(pTHX_ const char* orig, NV* value, const STRLEN len) if ((endp = S_my_atof_infnan(aTHX_ s, negative, send, value))) return endp; + /* strtold() accepts 0x-prefixed hex and in POSIX implementations, + 0b-prefixed binary numbers, which is backward incompatible + */ + if ((len == 0 || len - (s-orig) >= 2) && *s == '0' && + (isALPHA_FOLD_EQ(s[1], 'x') || isALPHA_FOLD_EQ(s[1], 'b'))) { + *value = 0; + return (char *)s+1; + } + /* If the length is passed in, the input string isn't NUL-terminated, * and in it turns out the function below assumes it is; therefore we * create a copy and NUL-terminate that */ @@ -1716,15 +1840,21 @@ Perl_my_atof3(pTHX_ const char* orig, NV* value, const STRLEN len) /* now apply the sign */ if (negative) result[2] = -result[2]; -#endif /* USE_PERL_ATOF */ *value = result[2]; return (char *)s; +#else /* USE_PERL_ATOF */ + /* If you see this error you both don't have strtod (or configured -Ud_strtod or + or it's long double/quadmath equivalent) and disabled USE_PERL_ATOF, thus + removing any way for perl to convert strings to floating point numbers. + */ +# error No mechanism to convert strings to numbers available +#endif } /* =for apidoc isinfnan -C is utility function that returns true if the NV +C is a utility function that returns true if the NV argument is either an infinity or a C, false otherwise. To test in more detail, use C and C. @@ -1748,7 +1878,7 @@ Perl_isinfnan(NV nv) } /* -=for apidoc +=for apidoc isinfnansv Checks whether the argument would be either an infinity or C when used as a number, but is careful not to trigger non-numeric or uninitialized