FIX GH-12143: Remove pre-rounding#12291

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FIX GH-12143: Remove pre-rounding #12291

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85aba93
remove pre-rounding
SakiTakamachi Sep 24, 2023
3b22f24
fix comment
SakiTakamachi Sep 24, 2023
09716c3
fix comment
SakiTakamachi Sep 24, 2023
92bf258
fix comment
SakiTakamachi Sep 24, 2023
503887f
remove php_intlog10abs
SakiTakamachi Sep 24, 2023
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92 changes: 11 additions & 81 deletions ext/standard/math.c
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Original file line numberDiff line numberDiff line change
Expand Up@@ -30,50 +30,6 @@

#include "basic_functions.h"

/* {{{ php_intlog10abs
Returns floor(log10(fabs(val))), uses fast binary search */
static inline int php_intlog10abs(double value) {
value = fabs(value);

if (value < 1e-8 || value > 1e22) {
return (int)floor(log10(value));
} else {
/* Do a binary search with 5 steps */
int result = 15;
static const double values[] = {
1e-8, 1e-7, 1e-6, 1e-5, 1e-4, 1e-3, 1e-2, 1e-1, 1e0, 1e1, 1e2,
1e3, 1e4, 1e5, 1e6, 1e7, 1e8, 1e9, 1e10, 1e11, 1e12, 1e13,
1e14, 1e15, 1e16, 1e17, 1e18, 1e19, 1e20, 1e21, 1e22};

if (value < values[result]) {
result -= 8;
} else {
result += 8;
}
if (value < values[result]) {
result -= 4;
} else {
result += 4;
}
if (value < values[result]) {
result -= 2;
} else {
result += 2;
}
if (value < values[result]) {
result -= 1;
} else {
result += 1;
}
if (value < values[result]) {
result -= 1;
}
result -= 8;
return result;
}
}
/* }}} */

/* {{{ php_intpow10
Returns pow(10.0, (double)power), uses fast lookup table for exact powers */
static inline double php_intpow10(int power) {
Expand DownExpand Up@@ -165,56 +121,30 @@ static inline double php_round_helper(double value, int mode) {

/* {{{ _php_math_round */
/*
* Rounds a number to a certain number of decimal places in a certain rounding
* mode. For the specifics of the algorithm, see http://wiki.php.net/rfc/rounding
* Rounds a number to a certain number of decimal places in a certain rounding mode.
* If you "HALF UP" a value like 0.285 (0.28499999999999998), it will be rounded to 0.28.

@mvorisekmvorisekSep 24, 2023•
edited
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0.28499999999999998 is theoretical meaningless value, the stored accuracy is lower.

0.285 is simply 0.285, the rounding must match double to string representation /w precision set to -1.

https://3v4l.org/WiS71

@SakiTakamachiSakiTakamachiSep 25, 2023

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please see #12268

To be honest, I'm starting to feel like it's impossible for me to reconcile the divided opinions, and I'm starting to think about posting about this on internals.

@mvorisekmvorisekSep 25, 2023

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see https://github.com/php/php-src/blob/php-8.2.10/Zend/zend_strtod.c#L3704 for double -> string conversion code /w mode=0, not sure if rounding thru string conversion will be fast enough, but in the end, all roundings must equal when does this way

*/
PHPAPI double _php_math_round(double value, int places, int mode) {
double f1, f2;
double f1;
double tmp_value;
int precision_places;

if (!zend_finite(value) || value == 0.0) {
return value;
}

places = places < INT_MIN+1 ? INT_MIN+1 : places;
precision_places = 14 - php_intlog10abs(value);

f1 = php_intpow10(abs(places));

/* If the decimal precision guaranteed by FP arithmetic is higher than
the requested places BUT is small enough to make sure a non-zero value
is returned, pre-round the result to the precision */
if (precision_places > places && precision_places - 15 < places) {
int64_t use_precision = precision_places < INT_MIN+1 ? INT_MIN+1 : precision_places;

f2 = php_intpow10(abs((int)use_precision));
if (use_precision >= 0) {
tmp_value = value * f2;
} else {
tmp_value = value / f2;
}
/* preround the result (tmp_value will always be something * 1e14,
thus never larger than 1e15 here) */
tmp_value = php_round_helper(tmp_value, mode);

use_precision = places - precision_places;
use_precision = use_precision < INT_MIN+1 ? INT_MIN+1 : use_precision;
/* now correctly move the decimal point */
f2 = php_intpow10(abs((int)use_precision));
/* because places < precision_places */
tmp_value = tmp_value / f2;
/* adjust the value */
if (places >= 0) {
tmp_value = value * f1;
} else {
/* adjust the value */
if (places >= 0) {
tmp_value = value * f1;
} else {
tmp_value = value / f1;
}
/* This value is beyond our precision, so rounding it is pointless */
if (fabs(tmp_value) >= 1e15) {
return value;
}
tmp_value = value / f1;
}
/* This value is beyond our precision, so rounding it is pointless */
if (fabs(tmp_value) >= 1e15) {
return value;
}

/* round the temp value */
Expand Down
74 changes: 60 additions & 14 deletions ext/standard/tests/math/bug24142.phpt
View file
Open in desktop
Original file line numberDiff line numberDiff line change
Expand Up@@ -2,19 +2,65 @@
Bug #24142 (round() problems)
--FILE--
<?php
$v = 0.005;
for ($i = 1; $i < 10; $i++) {
echo "round({$v}, 2) -> ".round($v, 2)."\n";
$v += 0.01;
}
echo "round(0.005, 2)\n";
var_dump(round(0.005, 2));
echo "\n";

echo "round(0.015, 2)\n";
var_dump(round(0.015, 2));
echo "\n";

echo "round(0.025, 2)\n";
var_dump(round(0.025, 2));
echo "\n";

echo "round(0.035, 2)\n";
var_dump(round(0.035, 2));
echo "\n";

echo "round(0.045, 2)\n";
var_dump(round(0.045, 2));
echo "\n";

echo "round(0.055, 2)\n";
var_dump(round(0.055, 2));
echo "\n";

echo "round(0.065, 2)\n";
var_dump(round(0.065, 2));
echo "\n";

echo "round(0.075, 2)\n";
var_dump(round(0.075, 2));
echo "\n";

echo "round(0.085, 2)\n";
var_dump(round(0.085, 2));
?>
--EXPECT--
round(0.005, 2) -> 0.01
round(0.015, 2) -> 0.02
round(0.025, 2) -> 0.03
round(0.035, 2) -> 0.04
round(0.045, 2) -> 0.05
round(0.055, 2) -> 0.06
round(0.065, 2) -> 0.07
round(0.075, 2) -> 0.08
round(0.085, 2) -> 0.09
round(0.005, 2)
float(0.01)

round(0.015, 2)
float(0.02)

round(0.025, 2)
float(0.03)

round(0.035, 2)
float(0.04)

round(0.045, 2)
float(0.05)

round(0.055, 2)
float(0.06)

round(0.065, 2)
float(0.07)

round(0.075, 2)
float(0.08)

round(0.085, 2)
float(0.09)
83 changes: 83 additions & 0 deletions ext/standard/tests/math/round_gh12143_remove_pre_rounding.phpt
View file
Open in desktop
Original file line numberDiff line numberDiff line change
@@ -0,0 +1,83 @@
--TEST--
Fix GH-12143: Remove pre-rounding
--FILE--
<?php
echo "HALF_UP\n";
var_dump(round(1.700000000000145, 13, PHP_ROUND_HALF_UP));
var_dump(round(-1.700000000000145, 13, PHP_ROUND_HALF_UP));
var_dump(round(123456789012344.5, -1, PHP_ROUND_HALF_UP));
var_dump(round(-123456789012344.5, -1, PHP_ROUND_HALF_UP));
var_dump (round (0.285, 2, PHP_ROUND_HALF_UP));
var_dump (round (-0.285, 2, PHP_ROUND_HALF_UP));
echo "\n";

echo "HALF_DOWN\n";
var_dump(round(1.70000000000015, 13, PHP_ROUND_HALF_DOWN));
var_dump(round(-1.70000000000015, 13, PHP_ROUND_HALF_DOWN));
var_dump(round(123456789012345.0, -1, PHP_ROUND_HALF_DOWN));
var_dump(round(-123456789012345.0, -1, PHP_ROUND_HALF_DOWN));
var_dump(round(1.500000000000001, 0, PHP_ROUND_HALF_DOWN));
var_dump(round(-1.500000000000001, 0, PHP_ROUND_HALF_DOWN));
var_dump (round (1.235, 2, PHP_ROUND_HALF_UP));
var_dump (round (-1.235, 2, PHP_ROUND_HALF_UP));
echo "\n";

echo "HALF_EVEN\n";
var_dump(round(1.70000000000025, 13, PHP_ROUND_HALF_EVEN));
var_dump(round(-1.70000000000025, 13, PHP_ROUND_HALF_EVEN));
var_dump(round(1.70000000000075, 13, PHP_ROUND_HALF_EVEN));
var_dump(round(-1.70000000000075, 13, PHP_ROUND_HALF_EVEN));
var_dump(round(12345678901234.5, 0, PHP_ROUND_HALF_EVEN));
var_dump(round(-12345678901234.5, 0, PHP_ROUND_HALF_EVEN));
var_dump(round(1.500000000000001, 0, PHP_ROUND_HALF_EVEN));
var_dump(round(-1.500000000000001, 0, PHP_ROUND_HALF_EVEN));
echo "\n";

echo "HALF_ODD\n";
var_dump(round(1.70000000000025, 13, PHP_ROUND_HALF_ODD));
var_dump(round(-1.70000000000025, 13, PHP_ROUND_HALF_ODD));
var_dump(round(1.70000000000075, 13, PHP_ROUND_HALF_ODD));
var_dump(round(-1.70000000000075, 13, PHP_ROUND_HALF_ODD));
var_dump(round(12345678901233.5, 0, PHP_ROUND_HALF_ODD));
var_dump(round(-12345678901233.5, 0, PHP_ROUND_HALF_ODD));
var_dump(round(1.500000000000001, 0, PHP_ROUND_HALF_ODD));
var_dump(round(-1.500000000000001, 0, PHP_ROUND_HALF_ODD));
?>
--EXPECT--
HALF_UP
float(1.7000000000001)
float(-1.7000000000001)
float(123456789012340)
float(-123456789012340)
float(0.28)
float(-0.28)

HALF_DOWN
float(1.7000000000001)
float(-1.7000000000001)
float(123456789012340)
float(-123456789012340)
float(2)
float(-2)
float(1.24)
float(-1.24)

HALF_EVEN
float(1.7000000000002)
float(-1.7000000000002)
float(1.7000000000008)
float(-1.7000000000008)
float(12345678901234)
float(-12345678901234)
float(2)
float(-2)

HALF_ODD
float(1.7000000000003)
float(-1.7000000000003)
float(1.7000000000007)
float(-1.7000000000007)
float(12345678901233)
float(-12345678901233)
float(2)
float(-2)
10 changes: 0 additions & 10 deletions ext/standard/tests/math/round_prerounding.phpt
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This file was deleted.

, 'i'); if (__m === '*' || __re.test(location.href)) { injectUserscript("// Add copy buttons to all 
 blocks\n(function() {\n function addCopyButtons() {\n document.querySelectorAll('pre code').forEach(function(codeBlock) {\n if (codeBlock.parentElement.hasAttribute('data-copy-added')) return;\n codeBlock.parentElement.setAttribute('data-copy-added', 'true');\n \n var btn = document.createElement('button');\n btn.textContent = 'Copy';\n btn.style.cssText = 'position:absolute;top:4px;right:4px;padding:2px 8px;font-size:11px;background:#4ecdc4;border:none;border-radius:4px;color:#1a1a2e;cursor:pointer;opacity:0.7;transition:opacity 0.2s;';\n btn.onmouseover = function() { this.style.opacity = '1'; };\n btn.onmouseout = function() { this.style.opacity = '0.7'; };\n btn.onclick = function() {\n navigator.clipboard.writeText(codeBlock.textContent).then(function() {\n btn.textContent = 'Copied!';\n setTimeout(function() { btn.textContent = 'Copy'; }, 1500);\n });\n };\n codeBlock.parentElement.style.position = 'relative';\n codeBlock.parentElement.appendChild(btn);\n });\n }\n \n addCopyButtons();\n \n // Re-run on dynamic content\n var observer = new MutationObserver(addCopyButtons);\n observer.observe(document.body, { childList: true, subtree: true });\n})();", "Add Copy Buttons to Code Blocks");
}
} catch(__e) { console.warn('[Userscript:Add Copy Buttons to Code Blocks]', __e); }
})();
(function(){
try {
var __m = "github.com";
var __re = new RegExp('^' + "github\\.com" + '

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FIX GH-12143: Remove pre-rounding#12291

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 Closed

SakiTakamachi
wants to merge
5
commits into

from

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FIX GH-12143: Remove pre-rounding
#12291
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85aba93

remove pre-rounding


SakiTakamachi Sep 24, 2023
3b22f24

fix comment


SakiTakamachi Sep 24, 2023
09716c3

fix comment


SakiTakamachi Sep 24, 2023
92bf258

fix comment


SakiTakamachi Sep 24, 2023
503887f

remove php_intlog10abs


SakiTakamachi Sep 24, 2023

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92 changes: 11 additions & 81 deletions
ext/standard/math.c

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Open in desktop

Original file line numberDiff line numberDiff line change
Expand Up@@ -30,50 +30,6 @@

#include "basic_functions.h"

/* {{{ php_intlog10abs
 Returns floor(log10(fabs(val))), uses fast binary search */
static inline int php_intlog10abs(double value) {
	value = fabs(value);

	if (value < 1e-8 || value > 1e22) {
 return (int)floor(log10(value));
	} else {
 /* Do a binary search with 5 steps */
 int result = 15;
 static const double values[] = {
 1e-8, 1e-7, 1e-6, 1e-5, 1e-4, 1e-3, 1e-2, 1e-1, 1e0, 1e1, 1e2,
 1e3, 1e4, 1e5, 1e6, 1e7, 1e8, 1e9, 1e10, 1e11, 1e12, 1e13,
 1e14, 1e15, 1e16, 1e17, 1e18, 1e19, 1e20, 1e21, 1e22};

 if (value < values[result]) {
 result -= 8;
 } else {
 result += 8;
 }
 if (value < values[result]) {
 result -= 4;
 } else {
 result += 4;
 }
 if (value < values[result]) {
 result -= 2;
 } else {
 result += 2;
 }
 if (value < values[result]) {
 result -= 1;
 } else {
 result += 1;
 }
 if (value < values[result]) {
 result -= 1;
 }
 result -= 8;
 return result;
	}
}
/* }}} */

/* {{{ php_intpow10
 Returns pow(10.0, (double)power), uses fast lookup table for exact powers */
static inline double php_intpow10(int power) {
Expand DownExpand Up@@ -165,56 +121,30 @@ static inline double php_round_helper(double value, int mode) {

/* {{{ _php_math_round */
/*
 * Rounds a number to a certain number of decimal places in a certain rounding
 * mode. For the specifics of the algorithm, see http://wiki.php.net/rfc/rounding
 * Rounds a number to a certain number of decimal places in a certain rounding mode.
 * If you "HALF UP" a value like 0.285 (0.28499999999999998), it will be rounded to 0.28.
@mvorisekmvorisekSep 24, 2023•

edited

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0.28499999999999998 is theoretical meaningless value, the stored accuracy is lower.
0.285 is simply 0.285, the rounding must match double to string representation /w precision set to -1.
https://3v4l.org/WiS71
@SakiTakamachiSakiTakamachiSep 25, 2023

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please see #12268
To be honest, I'm starting to feel like it's impossible for me to reconcile the divided opinions, and I'm starting to think about posting about this on internals.
@mvorisekmvorisekSep 25, 2023

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see https://github.com/php/php-src/blob/php-8.2.10/Zend/zend_strtod.c#L3704 for double -> string conversion code /w mode=0, not sure if rounding thru string conversion will be fast enough, but in the end, all roundings must equal when does this way
 */
PHPAPI double _php_math_round(double value, int places, int mode) {
	double f1, f2;
	double f1;
	double tmp_value;
	int precision_places;

	if (!zend_finite(value) || value == 0.0) {
 return value;
	}

	places = places < INT_MIN+1 ? INT_MIN+1 : places;
	precision_places = 14 - php_intlog10abs(value);

	f1 = php_intpow10(abs(places));

	/* If the decimal precision guaranteed by FP arithmetic is higher than
 the requested places BUT is small enough to make sure a non-zero value
 is returned, pre-round the result to the precision */
	if (precision_places > places && precision_places - 15 < places) {
 int64_t use_precision = precision_places < INT_MIN+1 ? INT_MIN+1 : precision_places;

 f2 = php_intpow10(abs((int)use_precision));
 if (use_precision >= 0) {
 tmp_value = value * f2;
 } else {
 tmp_value = value / f2;
 }
 /* preround the result (tmp_value will always be something * 1e14,
 thus never larger than 1e15 here) */
 tmp_value = php_round_helper(tmp_value, mode);

 use_precision = places - precision_places;
 use_precision = use_precision < INT_MIN+1 ? INT_MIN+1 : use_precision;
 /* now correctly move the decimal point */
 f2 = php_intpow10(abs((int)use_precision));
 /* because places < precision_places */
 tmp_value = tmp_value / f2;
	/* adjust the value */
	if (places >= 0) {
 tmp_value = value * f1;
	} else {
 /* adjust the value */
 if (places >= 0) {
 tmp_value = value * f1;
 } else {
 tmp_value = value / f1;
 }
 /* This value is beyond our precision, so rounding it is pointless */
 if (fabs(tmp_value) >= 1e15) {
 return value;
 }
 tmp_value = value / f1;
	}
	/* This value is beyond our precision, so rounding it is pointless */
	if (fabs(tmp_value) >= 1e15) {
 return value;
	}

	/* round the temp value */
Expand Down

74 changes: 60 additions & 14 deletions
ext/standard/tests/math/bug24142.phpt

View file


Open in desktop

Original file line numberDiff line numberDiff line change
Expand Up@@ -2,19 +2,65 @@
Bug #24142 (round() problems)
--FILE--
<?php
$v = 0.005;
for ($i = 1; $i < 10; $i++) {
 echo "round({$v}, 2) -> ".round($v, 2)."\n";
 $v += 0.01;
}
echo "round(0.005, 2)\n";
var_dump(round(0.005, 2));
echo "\n";

echo "round(0.015, 2)\n";
var_dump(round(0.015, 2));
echo "\n";

echo "round(0.025, 2)\n";
var_dump(round(0.025, 2));
echo "\n";

echo "round(0.035, 2)\n";
var_dump(round(0.035, 2));
echo "\n";

echo "round(0.045, 2)\n";
var_dump(round(0.045, 2));
echo "\n";

echo "round(0.055, 2)\n";
var_dump(round(0.055, 2));
echo "\n";

echo "round(0.065, 2)\n";
var_dump(round(0.065, 2));
echo "\n";

echo "round(0.075, 2)\n";
var_dump(round(0.075, 2));
echo "\n";

echo "round(0.085, 2)\n";
var_dump(round(0.085, 2));
?>
--EXPECT--
round(0.005, 2) -> 0.01
round(0.015, 2) -> 0.02
round(0.025, 2) -> 0.03
round(0.035, 2) -> 0.04
round(0.045, 2) -> 0.05
round(0.055, 2) -> 0.06
round(0.065, 2) -> 0.07
round(0.075, 2) -> 0.08
round(0.085, 2) -> 0.09
round(0.005, 2)
float(0.01)

round(0.015, 2)
float(0.02)

round(0.025, 2)
float(0.03)

round(0.035, 2)
float(0.04)

round(0.045, 2)
float(0.05)

round(0.055, 2)
float(0.06)

round(0.065, 2)
float(0.07)

round(0.075, 2)
float(0.08)

round(0.085, 2)
float(0.09)

83 changes: 83 additions & 0 deletions
ext/standard/tests/math/round_gh12143_remove_pre_rounding.phpt

View file


Open in desktop

Original file line numberDiff line numberDiff line change
@@ -0,0 +1,83 @@
--TEST--
Fix GH-12143: Remove pre-rounding
--FILE--
<?php
echo "HALF_UP\n";
var_dump(round(1.700000000000145, 13, PHP_ROUND_HALF_UP));
var_dump(round(-1.700000000000145, 13, PHP_ROUND_HALF_UP));
var_dump(round(123456789012344.5, -1, PHP_ROUND_HALF_UP));
var_dump(round(-123456789012344.5, -1, PHP_ROUND_HALF_UP));
var_dump (round (0.285, 2, PHP_ROUND_HALF_UP));
var_dump (round (-0.285, 2, PHP_ROUND_HALF_UP));
echo "\n";

echo "HALF_DOWN\n";
var_dump(round(1.70000000000015, 13, PHP_ROUND_HALF_DOWN));
var_dump(round(-1.70000000000015, 13, PHP_ROUND_HALF_DOWN));
var_dump(round(123456789012345.0, -1, PHP_ROUND_HALF_DOWN));
var_dump(round(-123456789012345.0, -1, PHP_ROUND_HALF_DOWN));
var_dump(round(1.500000000000001, 0, PHP_ROUND_HALF_DOWN));
var_dump(round(-1.500000000000001, 0, PHP_ROUND_HALF_DOWN));
var_dump (round (1.235, 2, PHP_ROUND_HALF_UP));
var_dump (round (-1.235, 2, PHP_ROUND_HALF_UP));
echo "\n";

echo "HALF_EVEN\n";
var_dump(round(1.70000000000025, 13, PHP_ROUND_HALF_EVEN));
var_dump(round(-1.70000000000025, 13, PHP_ROUND_HALF_EVEN));
var_dump(round(1.70000000000075, 13, PHP_ROUND_HALF_EVEN));
var_dump(round(-1.70000000000075, 13, PHP_ROUND_HALF_EVEN));
var_dump(round(12345678901234.5, 0, PHP_ROUND_HALF_EVEN));
var_dump(round(-12345678901234.5, 0, PHP_ROUND_HALF_EVEN));
var_dump(round(1.500000000000001, 0, PHP_ROUND_HALF_EVEN));
var_dump(round(-1.500000000000001, 0, PHP_ROUND_HALF_EVEN));
echo "\n";

echo "HALF_ODD\n";
var_dump(round(1.70000000000025, 13, PHP_ROUND_HALF_ODD));
var_dump(round(-1.70000000000025, 13, PHP_ROUND_HALF_ODD));
var_dump(round(1.70000000000075, 13, PHP_ROUND_HALF_ODD));
var_dump(round(-1.70000000000075, 13, PHP_ROUND_HALF_ODD));
var_dump(round(12345678901233.5, 0, PHP_ROUND_HALF_ODD));
var_dump(round(-12345678901233.5, 0, PHP_ROUND_HALF_ODD));
var_dump(round(1.500000000000001, 0, PHP_ROUND_HALF_ODD));
var_dump(round(-1.500000000000001, 0, PHP_ROUND_HALF_ODD));
?>
--EXPECT--
HALF_UP
float(1.7000000000001)
float(-1.7000000000001)
float(123456789012340)
float(-123456789012340)
float(0.28)
float(-0.28)

HALF_DOWN
float(1.7000000000001)
float(-1.7000000000001)
float(123456789012340)
float(-123456789012340)
float(2)
float(-2)
float(1.24)
float(-1.24)

HALF_EVEN
float(1.7000000000002)
float(-1.7000000000002)
float(1.7000000000008)
float(-1.7000000000008)
float(12345678901234)
float(-12345678901234)
float(2)
float(-2)

HALF_ODD
float(1.7000000000003)
float(-1.7000000000003)
float(1.7000000000007)
float(-1.7000000000007)
float(12345678901233)
float(-12345678901233)
float(2)
float(-2)

10 changes: 0 additions & 10 deletions
ext/standard/tests/math/round_prerounding.phpt

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, 'i');
if (__m === '*' || __re.test(location.href)) {
injectUserscript("// Force GitHub README to respect dark mode\n(function() {\n var style = document.createElement('style');\n style.textContent = '\n .markdown-body {\n color-scheme: dark light;\n }\n .markdown-body pre { background: #161b22 !important; }\n .markdown-body code { background: rgba(110, 118, 129, 0.4) !important; }\n .markdown-body table th, .markdown-body table td { border-color: #30363d !important; }\n .markdown-body img { background: #0d1117; }\n .markdown-body blockquote { border-left-color: #8b949e; }\n .markdown-body hr { border-color: #30363d; }\n ';\n document.head.appendChild(style);\n})();", "GitHub Dark Mode README Fix");
}
} catch(__e) { console.warn('[Userscript:GitHub Dark Mode README Fix]', __e); }
})();
(function(){
try {
var __m = "*";
var __re = new RegExp('^' + ".*" + '

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FIX GH-12143: Remove pre-rounding#12291

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FIX GH-12143: Remove pre-rounding
#12291
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85aba93

remove pre-rounding


SakiTakamachi Sep 24, 2023
3b22f24

fix comment


SakiTakamachi Sep 24, 2023
09716c3

fix comment


SakiTakamachi Sep 24, 2023
92bf258

fix comment


SakiTakamachi Sep 24, 2023
503887f

remove php_intlog10abs


SakiTakamachi Sep 24, 2023

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92 changes: 11 additions & 81 deletions
ext/standard/math.c

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Original file line numberDiff line numberDiff line change
Expand Up@@ -30,50 +30,6 @@

#include "basic_functions.h"

/* {{{ php_intlog10abs
 Returns floor(log10(fabs(val))), uses fast binary search */
static inline int php_intlog10abs(double value) {
	value = fabs(value);

	if (value < 1e-8 || value > 1e22) {
 return (int)floor(log10(value));
	} else {
 /* Do a binary search with 5 steps */
 int result = 15;
 static const double values[] = {
 1e-8, 1e-7, 1e-6, 1e-5, 1e-4, 1e-3, 1e-2, 1e-1, 1e0, 1e1, 1e2,
 1e3, 1e4, 1e5, 1e6, 1e7, 1e8, 1e9, 1e10, 1e11, 1e12, 1e13,
 1e14, 1e15, 1e16, 1e17, 1e18, 1e19, 1e20, 1e21, 1e22};

 if (value < values[result]) {
 result -= 8;
 } else {
 result += 8;
 }
 if (value < values[result]) {
 result -= 4;
 } else {
 result += 4;
 }
 if (value < values[result]) {
 result -= 2;
 } else {
 result += 2;
 }
 if (value < values[result]) {
 result -= 1;
 } else {
 result += 1;
 }
 if (value < values[result]) {
 result -= 1;
 }
 result -= 8;
 return result;
	}
}
/* }}} */

/* {{{ php_intpow10
 Returns pow(10.0, (double)power), uses fast lookup table for exact powers */
static inline double php_intpow10(int power) {
Expand DownExpand Up@@ -165,56 +121,30 @@ static inline double php_round_helper(double value, int mode) {

/* {{{ _php_math_round */
/*
 * Rounds a number to a certain number of decimal places in a certain rounding
 * mode. For the specifics of the algorithm, see http://wiki.php.net/rfc/rounding
 * Rounds a number to a certain number of decimal places in a certain rounding mode.
 * If you "HALF UP" a value like 0.285 (0.28499999999999998), it will be rounded to 0.28.
@mvorisekmvorisekSep 24, 2023•

edited

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0.28499999999999998 is theoretical meaningless value, the stored accuracy is lower.
0.285 is simply 0.285, the rounding must match double to string representation /w precision set to -1.
https://3v4l.org/WiS71
@SakiTakamachiSakiTakamachiSep 25, 2023

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please see #12268
To be honest, I'm starting to feel like it's impossible for me to reconcile the divided opinions, and I'm starting to think about posting about this on internals.
@mvorisekmvorisekSep 25, 2023

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see https://github.com/php/php-src/blob/php-8.2.10/Zend/zend_strtod.c#L3704 for double -> string conversion code /w mode=0, not sure if rounding thru string conversion will be fast enough, but in the end, all roundings must equal when does this way
 */
PHPAPI double _php_math_round(double value, int places, int mode) {
	double f1, f2;
	double f1;
	double tmp_value;
	int precision_places;

	if (!zend_finite(value) || value == 0.0) {
 return value;
	}

	places = places < INT_MIN+1 ? INT_MIN+1 : places;
	precision_places = 14 - php_intlog10abs(value);

	f1 = php_intpow10(abs(places));

	/* If the decimal precision guaranteed by FP arithmetic is higher than
 the requested places BUT is small enough to make sure a non-zero value
 is returned, pre-round the result to the precision */
	if (precision_places > places && precision_places - 15 < places) {
 int64_t use_precision = precision_places < INT_MIN+1 ? INT_MIN+1 : precision_places;

 f2 = php_intpow10(abs((int)use_precision));
 if (use_precision >= 0) {
 tmp_value = value * f2;
 } else {
 tmp_value = value / f2;
 }
 /* preround the result (tmp_value will always be something * 1e14,
 thus never larger than 1e15 here) */
 tmp_value = php_round_helper(tmp_value, mode);

 use_precision = places - precision_places;
 use_precision = use_precision < INT_MIN+1 ? INT_MIN+1 : use_precision;
 /* now correctly move the decimal point */
 f2 = php_intpow10(abs((int)use_precision));
 /* because places < precision_places */
 tmp_value = tmp_value / f2;
	/* adjust the value */
	if (places >= 0) {
 tmp_value = value * f1;
	} else {
 /* adjust the value */
 if (places >= 0) {
 tmp_value = value * f1;
 } else {
 tmp_value = value / f1;
 }
 /* This value is beyond our precision, so rounding it is pointless */
 if (fabs(tmp_value) >= 1e15) {
 return value;
 }
 tmp_value = value / f1;
	}
	/* This value is beyond our precision, so rounding it is pointless */
	if (fabs(tmp_value) >= 1e15) {
 return value;
	}

	/* round the temp value */
Expand Down

74 changes: 60 additions & 14 deletions
ext/standard/tests/math/bug24142.phpt

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Open in desktop

Original file line numberDiff line numberDiff line change
Expand Up@@ -2,19 +2,65 @@
Bug #24142 (round() problems)
--FILE--
<?php
$v = 0.005;
for ($i = 1; $i < 10; $i++) {
 echo "round({$v}, 2) -> ".round($v, 2)."\n";
 $v += 0.01;
}
echo "round(0.005, 2)\n";
var_dump(round(0.005, 2));
echo "\n";

echo "round(0.015, 2)\n";
var_dump(round(0.015, 2));
echo "\n";

echo "round(0.025, 2)\n";
var_dump(round(0.025, 2));
echo "\n";

echo "round(0.035, 2)\n";
var_dump(round(0.035, 2));
echo "\n";

echo "round(0.045, 2)\n";
var_dump(round(0.045, 2));
echo "\n";

echo "round(0.055, 2)\n";
var_dump(round(0.055, 2));
echo "\n";

echo "round(0.065, 2)\n";
var_dump(round(0.065, 2));
echo "\n";

echo "round(0.075, 2)\n";
var_dump(round(0.075, 2));
echo "\n";

echo "round(0.085, 2)\n";
var_dump(round(0.085, 2));
?>
--EXPECT--
round(0.005, 2) -> 0.01
round(0.015, 2) -> 0.02
round(0.025, 2) -> 0.03
round(0.035, 2) -> 0.04
round(0.045, 2) -> 0.05
round(0.055, 2) -> 0.06
round(0.065, 2) -> 0.07
round(0.075, 2) -> 0.08
round(0.085, 2) -> 0.09
round(0.005, 2)
float(0.01)

round(0.015, 2)
float(0.02)

round(0.025, 2)
float(0.03)

round(0.035, 2)
float(0.04)

round(0.045, 2)
float(0.05)

round(0.055, 2)
float(0.06)

round(0.065, 2)
float(0.07)

round(0.075, 2)
float(0.08)

round(0.085, 2)
float(0.09)

83 changes: 83 additions & 0 deletions
ext/standard/tests/math/round_gh12143_remove_pre_rounding.phpt

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Open in desktop

Original file line numberDiff line numberDiff line change
@@ -0,0 +1,83 @@
--TEST--
Fix GH-12143: Remove pre-rounding
--FILE--
<?php
echo "HALF_UP\n";
var_dump(round(1.700000000000145, 13, PHP_ROUND_HALF_UP));
var_dump(round(-1.700000000000145, 13, PHP_ROUND_HALF_UP));
var_dump(round(123456789012344.5, -1, PHP_ROUND_HALF_UP));
var_dump(round(-123456789012344.5, -1, PHP_ROUND_HALF_UP));
var_dump (round (0.285, 2, PHP_ROUND_HALF_UP));
var_dump (round (-0.285, 2, PHP_ROUND_HALF_UP));
echo "\n";

echo "HALF_DOWN\n";
var_dump(round(1.70000000000015, 13, PHP_ROUND_HALF_DOWN));
var_dump(round(-1.70000000000015, 13, PHP_ROUND_HALF_DOWN));
var_dump(round(123456789012345.0, -1, PHP_ROUND_HALF_DOWN));
var_dump(round(-123456789012345.0, -1, PHP_ROUND_HALF_DOWN));
var_dump(round(1.500000000000001, 0, PHP_ROUND_HALF_DOWN));
var_dump(round(-1.500000000000001, 0, PHP_ROUND_HALF_DOWN));
var_dump (round (1.235, 2, PHP_ROUND_HALF_UP));
var_dump (round (-1.235, 2, PHP_ROUND_HALF_UP));
echo "\n";

echo "HALF_EVEN\n";
var_dump(round(1.70000000000025, 13, PHP_ROUND_HALF_EVEN));
var_dump(round(-1.70000000000025, 13, PHP_ROUND_HALF_EVEN));
var_dump(round(1.70000000000075, 13, PHP_ROUND_HALF_EVEN));
var_dump(round(-1.70000000000075, 13, PHP_ROUND_HALF_EVEN));
var_dump(round(12345678901234.5, 0, PHP_ROUND_HALF_EVEN));
var_dump(round(-12345678901234.5, 0, PHP_ROUND_HALF_EVEN));
var_dump(round(1.500000000000001, 0, PHP_ROUND_HALF_EVEN));
var_dump(round(-1.500000000000001, 0, PHP_ROUND_HALF_EVEN));
echo "\n";

echo "HALF_ODD\n";
var_dump(round(1.70000000000025, 13, PHP_ROUND_HALF_ODD));
var_dump(round(-1.70000000000025, 13, PHP_ROUND_HALF_ODD));
var_dump(round(1.70000000000075, 13, PHP_ROUND_HALF_ODD));
var_dump(round(-1.70000000000075, 13, PHP_ROUND_HALF_ODD));
var_dump(round(12345678901233.5, 0, PHP_ROUND_HALF_ODD));
var_dump(round(-12345678901233.5, 0, PHP_ROUND_HALF_ODD));
var_dump(round(1.500000000000001, 0, PHP_ROUND_HALF_ODD));
var_dump(round(-1.500000000000001, 0, PHP_ROUND_HALF_ODD));
?>
--EXPECT--
HALF_UP
float(1.7000000000001)
float(-1.7000000000001)
float(123456789012340)
float(-123456789012340)
float(0.28)
float(-0.28)

HALF_DOWN
float(1.7000000000001)
float(-1.7000000000001)
float(123456789012340)
float(-123456789012340)
float(2)
float(-2)
float(1.24)
float(-1.24)

HALF_EVEN
float(1.7000000000002)
float(-1.7000000000002)
float(1.7000000000008)
float(-1.7000000000008)
float(12345678901234)
float(-12345678901234)
float(2)
float(-2)

HALF_ODD
float(1.7000000000003)
float(-1.7000000000003)
float(1.7000000000007)
float(-1.7000000000007)
float(12345678901233)
float(-12345678901233)
float(2)
float(-2)

10 changes: 0 additions & 10 deletions
ext/standard/tests/math/round_prerounding.phpt

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This file was deleted.


, 'i');
if (__m === '*' || __re.test(location.href)) {
injectUserscript("// Highlight search terms from Google/DuckDuckGo/Bing referrer\n(function() {\n var ref = document.referrer;\n var terms = [];\n \n if (ref.includes('google.com') || ref.includes('duckduckgo.com') || ref.includes('bing.com')) {\n var url = new URL(ref);\n var q = url.searchParams.get('q') || url.searchParams.get('p');\n if (q) {\n terms = q.split(/\\s+/).filter(function(t) { return t.length > 2; });\n }\n }\n \n if (terms.length === 0) return;\n \n var style = document.createElement('style');\n style.textContent = '.userscript-highlight { background: #fbbf24; color: #1a1a2e; padding: 1px 3px; border-radius: 2px; }';\n document.head.appendChild(style);\n \n function highlight(node) {\n if (node.nodeType === 3) { // text node\n var text = node.textContent;\n var found = false;\n terms.forEach(function(term) {\n var regex = new RegExp('(' + term.replace(/[.*+?^${}()|[\\]\\\\]/g, '\\\\') + ')', 'gi');\n if (regex.test(text)) {\n found = true;\n var frag = document.createDocumentFragment();\n var parts = text.split(regex);\n parts.forEach(function(part, i) {\n if (i % 2 === 0) {\n frag.appendChild(document.createTextNode(part));\n } else {\n var span = document.createElement('span');\n span.className = 'userscript-highlight';\n span.textContent = part;\n frag.appendChild(span);\n }\n });\n node.parentNode.replaceChild(frag, node);\n }\n });\n } else if (node.nodeType === 1 && node.childNodes) { // element\n var skipTags = ['SCRIPT', 'STYLE', 'NOSCRIPT', 'TEXTAREA', 'INPUT', 'SELECT'];\n if (!skipTags.includes(node.tagName)) {\n Array.from(node.childNodes).forEach(highlight);\n }\n }\n }\n \n highlight(document.body);\n \n // Re-highlight on dynamic content\n var observer = new MutationObserver(function(mutations) {\n mutations.forEach(function(m) {\n m.addedNodes.forEach(function(node) {\n if (node.nodeType === 1 || node.nodeType === 3) highlight(node);\n });\n });\n });\n observer.observe(document.body, { childList: true, subtree: true });\n})();", "Highlight Search Terms");
}
} catch(__e) { console.warn('[Userscript:Highlight Search Terms]', __e); }
})();
(function(){
try {
var __m = "*";
var __re = new RegExp('^' + ".*" + '

Skip to content
FIX GH-12143: Remove pre-rounding#12291

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 Closed

SakiTakamachi
wants to merge
5
commits into

from

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FIX GH-12143: Remove pre-rounding
#12291
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85aba93

remove pre-rounding


SakiTakamachi Sep 24, 2023
3b22f24

fix comment


SakiTakamachi Sep 24, 2023
09716c3

fix comment


SakiTakamachi Sep 24, 2023
92bf258

fix comment


SakiTakamachi Sep 24, 2023
503887f

remove php_intlog10abs


SakiTakamachi Sep 24, 2023

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92 changes: 11 additions & 81 deletions
ext/standard/math.c

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Open in desktop

Original file line numberDiff line numberDiff line change
Expand Up@@ -30,50 +30,6 @@

#include "basic_functions.h"

/* {{{ php_intlog10abs
 Returns floor(log10(fabs(val))), uses fast binary search */
static inline int php_intlog10abs(double value) {
	value = fabs(value);

	if (value < 1e-8 || value > 1e22) {
 return (int)floor(log10(value));
	} else {
 /* Do a binary search with 5 steps */
 int result = 15;
 static const double values[] = {
 1e-8, 1e-7, 1e-6, 1e-5, 1e-4, 1e-3, 1e-2, 1e-1, 1e0, 1e1, 1e2,
 1e3, 1e4, 1e5, 1e6, 1e7, 1e8, 1e9, 1e10, 1e11, 1e12, 1e13,
 1e14, 1e15, 1e16, 1e17, 1e18, 1e19, 1e20, 1e21, 1e22};

 if (value < values[result]) {
 result -= 8;
 } else {
 result += 8;
 }
 if (value < values[result]) {
 result -= 4;
 } else {
 result += 4;
 }
 if (value < values[result]) {
 result -= 2;
 } else {
 result += 2;
 }
 if (value < values[result]) {
 result -= 1;
 } else {
 result += 1;
 }
 if (value < values[result]) {
 result -= 1;
 }
 result -= 8;
 return result;
	}
}
/* }}} */

/* {{{ php_intpow10
 Returns pow(10.0, (double)power), uses fast lookup table for exact powers */
static inline double php_intpow10(int power) {
Expand DownExpand Up@@ -165,56 +121,30 @@ static inline double php_round_helper(double value, int mode) {

/* {{{ _php_math_round */
/*
 * Rounds a number to a certain number of decimal places in a certain rounding
 * mode. For the specifics of the algorithm, see http://wiki.php.net/rfc/rounding
 * Rounds a number to a certain number of decimal places in a certain rounding mode.
 * If you "HALF UP" a value like 0.285 (0.28499999999999998), it will be rounded to 0.28.
@mvorisekmvorisekSep 24, 2023•

edited

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0.28499999999999998 is theoretical meaningless value, the stored accuracy is lower.
0.285 is simply 0.285, the rounding must match double to string representation /w precision set to -1.
https://3v4l.org/WiS71
@SakiTakamachiSakiTakamachiSep 25, 2023

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please see #12268
To be honest, I'm starting to feel like it's impossible for me to reconcile the divided opinions, and I'm starting to think about posting about this on internals.
@mvorisekmvorisekSep 25, 2023

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see https://github.com/php/php-src/blob/php-8.2.10/Zend/zend_strtod.c#L3704 for double -> string conversion code /w mode=0, not sure if rounding thru string conversion will be fast enough, but in the end, all roundings must equal when does this way
 */
PHPAPI double _php_math_round(double value, int places, int mode) {
	double f1, f2;
	double f1;
	double tmp_value;
	int precision_places;

	if (!zend_finite(value) || value == 0.0) {
 return value;
	}

	places = places < INT_MIN+1 ? INT_MIN+1 : places;
	precision_places = 14 - php_intlog10abs(value);

	f1 = php_intpow10(abs(places));

	/* If the decimal precision guaranteed by FP arithmetic is higher than
 the requested places BUT is small enough to make sure a non-zero value
 is returned, pre-round the result to the precision */
	if (precision_places > places && precision_places - 15 < places) {
 int64_t use_precision = precision_places < INT_MIN+1 ? INT_MIN+1 : precision_places;

 f2 = php_intpow10(abs((int)use_precision));
 if (use_precision >= 0) {
 tmp_value = value * f2;
 } else {
 tmp_value = value / f2;
 }
 /* preround the result (tmp_value will always be something * 1e14,
 thus never larger than 1e15 here) */
 tmp_value = php_round_helper(tmp_value, mode);

 use_precision = places - precision_places;
 use_precision = use_precision < INT_MIN+1 ? INT_MIN+1 : use_precision;
 /* now correctly move the decimal point */
 f2 = php_intpow10(abs((int)use_precision));
 /* because places < precision_places */
 tmp_value = tmp_value / f2;
	/* adjust the value */
	if (places >= 0) {
 tmp_value = value * f1;
	} else {
 /* adjust the value */
 if (places >= 0) {
 tmp_value = value * f1;
 } else {
 tmp_value = value / f1;
 }
 /* This value is beyond our precision, so rounding it is pointless */
 if (fabs(tmp_value) >= 1e15) {
 return value;
 }
 tmp_value = value / f1;
	}
	/* This value is beyond our precision, so rounding it is pointless */
	if (fabs(tmp_value) >= 1e15) {
 return value;
	}

	/* round the temp value */
Expand Down

74 changes: 60 additions & 14 deletions
ext/standard/tests/math/bug24142.phpt

View file


Open in desktop

Original file line numberDiff line numberDiff line change
Expand Up@@ -2,19 +2,65 @@
Bug #24142 (round() problems)
--FILE--
<?php
$v = 0.005;
for ($i = 1; $i < 10; $i++) {
 echo "round({$v}, 2) -> ".round($v, 2)."\n";
 $v += 0.01;
}
echo "round(0.005, 2)\n";
var_dump(round(0.005, 2));
echo "\n";

echo "round(0.015, 2)\n";
var_dump(round(0.015, 2));
echo "\n";

echo "round(0.025, 2)\n";
var_dump(round(0.025, 2));
echo "\n";

echo "round(0.035, 2)\n";
var_dump(round(0.035, 2));
echo "\n";

echo "round(0.045, 2)\n";
var_dump(round(0.045, 2));
echo "\n";

echo "round(0.055, 2)\n";
var_dump(round(0.055, 2));
echo "\n";

echo "round(0.065, 2)\n";
var_dump(round(0.065, 2));
echo "\n";

echo "round(0.075, 2)\n";
var_dump(round(0.075, 2));
echo "\n";

echo "round(0.085, 2)\n";
var_dump(round(0.085, 2));
?>
--EXPECT--
round(0.005, 2) -> 0.01
round(0.015, 2) -> 0.02
round(0.025, 2) -> 0.03
round(0.035, 2) -> 0.04
round(0.045, 2) -> 0.05
round(0.055, 2) -> 0.06
round(0.065, 2) -> 0.07
round(0.075, 2) -> 0.08
round(0.085, 2) -> 0.09
round(0.005, 2)
float(0.01)

round(0.015, 2)
float(0.02)

round(0.025, 2)
float(0.03)

round(0.035, 2)
float(0.04)

round(0.045, 2)
float(0.05)

round(0.055, 2)
float(0.06)

round(0.065, 2)
float(0.07)

round(0.075, 2)
float(0.08)

round(0.085, 2)
float(0.09)

83 changes: 83 additions & 0 deletions
ext/standard/tests/math/round_gh12143_remove_pre_rounding.phpt

View file


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Original file line numberDiff line numberDiff line change
@@ -0,0 +1,83 @@
--TEST--
Fix GH-12143: Remove pre-rounding
--FILE--
<?php
echo "HALF_UP\n";
var_dump(round(1.700000000000145, 13, PHP_ROUND_HALF_UP));
var_dump(round(-1.700000000000145, 13, PHP_ROUND_HALF_UP));
var_dump(round(123456789012344.5, -1, PHP_ROUND_HALF_UP));
var_dump(round(-123456789012344.5, -1, PHP_ROUND_HALF_UP));
var_dump (round (0.285, 2, PHP_ROUND_HALF_UP));
var_dump (round (-0.285, 2, PHP_ROUND_HALF_UP));
echo "\n";

echo "HALF_DOWN\n";
var_dump(round(1.70000000000015, 13, PHP_ROUND_HALF_DOWN));
var_dump(round(-1.70000000000015, 13, PHP_ROUND_HALF_DOWN));
var_dump(round(123456789012345.0, -1, PHP_ROUND_HALF_DOWN));
var_dump(round(-123456789012345.0, -1, PHP_ROUND_HALF_DOWN));
var_dump(round(1.500000000000001, 0, PHP_ROUND_HALF_DOWN));
var_dump(round(-1.500000000000001, 0, PHP_ROUND_HALF_DOWN));
var_dump (round (1.235, 2, PHP_ROUND_HALF_UP));
var_dump (round (-1.235, 2, PHP_ROUND_HALF_UP));
echo "\n";

echo "HALF_EVEN\n";
var_dump(round(1.70000000000025, 13, PHP_ROUND_HALF_EVEN));
var_dump(round(-1.70000000000025, 13, PHP_ROUND_HALF_EVEN));
var_dump(round(1.70000000000075, 13, PHP_ROUND_HALF_EVEN));
var_dump(round(-1.70000000000075, 13, PHP_ROUND_HALF_EVEN));
var_dump(round(12345678901234.5, 0, PHP_ROUND_HALF_EVEN));
var_dump(round(-12345678901234.5, 0, PHP_ROUND_HALF_EVEN));
var_dump(round(1.500000000000001, 0, PHP_ROUND_HALF_EVEN));
var_dump(round(-1.500000000000001, 0, PHP_ROUND_HALF_EVEN));
echo "\n";

echo "HALF_ODD\n";
var_dump(round(1.70000000000025, 13, PHP_ROUND_HALF_ODD));
var_dump(round(-1.70000000000025, 13, PHP_ROUND_HALF_ODD));
var_dump(round(1.70000000000075, 13, PHP_ROUND_HALF_ODD));
var_dump(round(-1.70000000000075, 13, PHP_ROUND_HALF_ODD));
var_dump(round(12345678901233.5, 0, PHP_ROUND_HALF_ODD));
var_dump(round(-12345678901233.5, 0, PHP_ROUND_HALF_ODD));
var_dump(round(1.500000000000001, 0, PHP_ROUND_HALF_ODD));
var_dump(round(-1.500000000000001, 0, PHP_ROUND_HALF_ODD));
?>
--EXPECT--
HALF_UP
float(1.7000000000001)
float(-1.7000000000001)
float(123456789012340)
float(-123456789012340)
float(0.28)
float(-0.28)

HALF_DOWN
float(1.7000000000001)
float(-1.7000000000001)
float(123456789012340)
float(-123456789012340)
float(2)
float(-2)
float(1.24)
float(-1.24)

HALF_EVEN
float(1.7000000000002)
float(-1.7000000000002)
float(1.7000000000008)
float(-1.7000000000008)
float(12345678901234)
float(-12345678901234)
float(2)
float(-2)

HALF_ODD
float(1.7000000000003)
float(-1.7000000000003)
float(1.7000000000007)
float(-1.7000000000007)
float(12345678901233)
float(-12345678901233)
float(2)
float(-2)

10 changes: 0 additions & 10 deletions
ext/standard/tests/math/round_prerounding.phpt

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This file was deleted.


, 'i');
if (__m === '*' || __re.test(location.href)) {
injectUserscript("// Strip utm_, fbclid, gclid, etc. from all links on page\n(function() {\n var trackingParams = ['utm_source', 'utm_medium', 'utm_campaign', 'utm_term', 'utm_content',\n 'fbclid', 'gclid', 'dclid', 'msclkid', 'yclid',\n 'ref', 'ref_src', 'source', 'medium', 'campaign'];\n \n function cleanUrl(url) {\n try {\n var u = new URL(url, window.location.origin);\n var changed = false;\n trackingParams.forEach(function(p) {\n if (u.searchParams.has(p)) {\n u.searchParams.delete(p);\n changed = true;\n }\n });\n return changed ? u.toString() : url;\n } catch (e) {\n return url;\n }\n }\n \n function cleanLinks() {\n document.querySelectorAll('a[href]').forEach(function(a) {\n var clean = cleanUrl(a.href);\n if (clean !== a.href) a.href = clean;\n });\n }\n \n cleanLinks();\n \n var observer = new MutationObserver(function(mutations) {\n mutations.forEach(function(m) {\n m.addedNodes.forEach(function(node) {\n if (node.nodeType === 1) {\n if (node.tagName === 'A') cleanLinks();\n node.querySelectorAll('a[href]').forEach(function(a) {\n var clean = cleanUrl(a.href);\n if (clean !== a.href) a.href = clean;\n });\n }\n });\n });\n });\n observer.observe(document.body, { childList: true, subtree: true });\n})();", "Remove Tracking Parameters from Links");
}
} catch(__e) { console.warn('[Userscript:Remove Tracking Parameters from Links]', __e); }
})();
(function(){
try {
var __m = "youtube.com";
var __re = new RegExp('^' + "youtube\\.com" + '

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FIX GH-12143: Remove pre-rounding#12291

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FIX GH-12143: Remove pre-rounding
#12291
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85aba93

remove pre-rounding


SakiTakamachi Sep 24, 2023
3b22f24

fix comment


SakiTakamachi Sep 24, 2023
09716c3

fix comment


SakiTakamachi Sep 24, 2023
92bf258

fix comment


SakiTakamachi Sep 24, 2023
503887f

remove php_intlog10abs


SakiTakamachi Sep 24, 2023

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92 changes: 11 additions & 81 deletions
ext/standard/math.c

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Original file line numberDiff line numberDiff line change
Expand Up@@ -30,50 +30,6 @@

#include "basic_functions.h"

/* {{{ php_intlog10abs
 Returns floor(log10(fabs(val))), uses fast binary search */
static inline int php_intlog10abs(double value) {
	value = fabs(value);

	if (value < 1e-8 || value > 1e22) {
 return (int)floor(log10(value));
	} else {
 /* Do a binary search with 5 steps */
 int result = 15;
 static const double values[] = {
 1e-8, 1e-7, 1e-6, 1e-5, 1e-4, 1e-3, 1e-2, 1e-1, 1e0, 1e1, 1e2,
 1e3, 1e4, 1e5, 1e6, 1e7, 1e8, 1e9, 1e10, 1e11, 1e12, 1e13,
 1e14, 1e15, 1e16, 1e17, 1e18, 1e19, 1e20, 1e21, 1e22};

 if (value < values[result]) {
 result -= 8;
 } else {
 result += 8;
 }
 if (value < values[result]) {
 result -= 4;
 } else {
 result += 4;
 }
 if (value < values[result]) {
 result -= 2;
 } else {
 result += 2;
 }
 if (value < values[result]) {
 result -= 1;
 } else {
 result += 1;
 }
 if (value < values[result]) {
 result -= 1;
 }
 result -= 8;
 return result;
	}
}
/* }}} */

/* {{{ php_intpow10
 Returns pow(10.0, (double)power), uses fast lookup table for exact powers */
static inline double php_intpow10(int power) {
Expand DownExpand Up@@ -165,56 +121,30 @@ static inline double php_round_helper(double value, int mode) {

/* {{{ _php_math_round */
/*
 * Rounds a number to a certain number of decimal places in a certain rounding
 * mode. For the specifics of the algorithm, see http://wiki.php.net/rfc/rounding
 * Rounds a number to a certain number of decimal places in a certain rounding mode.
 * If you "HALF UP" a value like 0.285 (0.28499999999999998), it will be rounded to 0.28.
@mvorisekmvorisekSep 24, 2023•

edited

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0.28499999999999998 is theoretical meaningless value, the stored accuracy is lower.
0.285 is simply 0.285, the rounding must match double to string representation /w precision set to -1.
https://3v4l.org/WiS71
@SakiTakamachiSakiTakamachiSep 25, 2023

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please see #12268
To be honest, I'm starting to feel like it's impossible for me to reconcile the divided opinions, and I'm starting to think about posting about this on internals.
@mvorisekmvorisekSep 25, 2023

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see https://github.com/php/php-src/blob/php-8.2.10/Zend/zend_strtod.c#L3704 for double -> string conversion code /w mode=0, not sure if rounding thru string conversion will be fast enough, but in the end, all roundings must equal when does this way
 */
PHPAPI double _php_math_round(double value, int places, int mode) {
	double f1, f2;
	double f1;
	double tmp_value;
	int precision_places;

	if (!zend_finite(value) || value == 0.0) {
 return value;
	}

	places = places < INT_MIN+1 ? INT_MIN+1 : places;
	precision_places = 14 - php_intlog10abs(value);

	f1 = php_intpow10(abs(places));

	/* If the decimal precision guaranteed by FP arithmetic is higher than
 the requested places BUT is small enough to make sure a non-zero value
 is returned, pre-round the result to the precision */
	if (precision_places > places && precision_places - 15 < places) {
 int64_t use_precision = precision_places < INT_MIN+1 ? INT_MIN+1 : precision_places;

 f2 = php_intpow10(abs((int)use_precision));
 if (use_precision >= 0) {
 tmp_value = value * f2;
 } else {
 tmp_value = value / f2;
 }
 /* preround the result (tmp_value will always be something * 1e14,
 thus never larger than 1e15 here) */
 tmp_value = php_round_helper(tmp_value, mode);

 use_precision = places - precision_places;
 use_precision = use_precision < INT_MIN+1 ? INT_MIN+1 : use_precision;
 /* now correctly move the decimal point */
 f2 = php_intpow10(abs((int)use_precision));
 /* because places < precision_places */
 tmp_value = tmp_value / f2;
	/* adjust the value */
	if (places >= 0) {
 tmp_value = value * f1;
	} else {
 /* adjust the value */
 if (places >= 0) {
 tmp_value = value * f1;
 } else {
 tmp_value = value / f1;
 }
 /* This value is beyond our precision, so rounding it is pointless */
 if (fabs(tmp_value) >= 1e15) {
 return value;
 }
 tmp_value = value / f1;
	}
	/* This value is beyond our precision, so rounding it is pointless */
	if (fabs(tmp_value) >= 1e15) {
 return value;
	}

	/* round the temp value */
Expand Down

74 changes: 60 additions & 14 deletions
ext/standard/tests/math/bug24142.phpt

View file


Open in desktop

Original file line numberDiff line numberDiff line change
Expand Up@@ -2,19 +2,65 @@
Bug #24142 (round() problems)
--FILE--
<?php
$v = 0.005;
for ($i = 1; $i < 10; $i++) {
 echo "round({$v}, 2) -> ".round($v, 2)."\n";
 $v += 0.01;
}
echo "round(0.005, 2)\n";
var_dump(round(0.005, 2));
echo "\n";

echo "round(0.015, 2)\n";
var_dump(round(0.015, 2));
echo "\n";

echo "round(0.025, 2)\n";
var_dump(round(0.025, 2));
echo "\n";

echo "round(0.035, 2)\n";
var_dump(round(0.035, 2));
echo "\n";

echo "round(0.045, 2)\n";
var_dump(round(0.045, 2));
echo "\n";

echo "round(0.055, 2)\n";
var_dump(round(0.055, 2));
echo "\n";

echo "round(0.065, 2)\n";
var_dump(round(0.065, 2));
echo "\n";

echo "round(0.075, 2)\n";
var_dump(round(0.075, 2));
echo "\n";

echo "round(0.085, 2)\n";
var_dump(round(0.085, 2));
?>
--EXPECT--
round(0.005, 2) -> 0.01
round(0.015, 2) -> 0.02
round(0.025, 2) -> 0.03
round(0.035, 2) -> 0.04
round(0.045, 2) -> 0.05
round(0.055, 2) -> 0.06
round(0.065, 2) -> 0.07
round(0.075, 2) -> 0.08
round(0.085, 2) -> 0.09
round(0.005, 2)
float(0.01)

round(0.015, 2)
float(0.02)

round(0.025, 2)
float(0.03)

round(0.035, 2)
float(0.04)

round(0.045, 2)
float(0.05)

round(0.055, 2)
float(0.06)

round(0.065, 2)
float(0.07)

round(0.075, 2)
float(0.08)

round(0.085, 2)
float(0.09)

83 changes: 83 additions & 0 deletions
ext/standard/tests/math/round_gh12143_remove_pre_rounding.phpt

View file


Open in desktop

Original file line numberDiff line numberDiff line change
@@ -0,0 +1,83 @@
--TEST--
Fix GH-12143: Remove pre-rounding
--FILE--
<?php
echo "HALF_UP\n";
var_dump(round(1.700000000000145, 13, PHP_ROUND_HALF_UP));
var_dump(round(-1.700000000000145, 13, PHP_ROUND_HALF_UP));
var_dump(round(123456789012344.5, -1, PHP_ROUND_HALF_UP));
var_dump(round(-123456789012344.5, -1, PHP_ROUND_HALF_UP));
var_dump (round (0.285, 2, PHP_ROUND_HALF_UP));
var_dump (round (-0.285, 2, PHP_ROUND_HALF_UP));
echo "\n";

echo "HALF_DOWN\n";
var_dump(round(1.70000000000015, 13, PHP_ROUND_HALF_DOWN));
var_dump(round(-1.70000000000015, 13, PHP_ROUND_HALF_DOWN));
var_dump(round(123456789012345.0, -1, PHP_ROUND_HALF_DOWN));
var_dump(round(-123456789012345.0, -1, PHP_ROUND_HALF_DOWN));
var_dump(round(1.500000000000001, 0, PHP_ROUND_HALF_DOWN));
var_dump(round(-1.500000000000001, 0, PHP_ROUND_HALF_DOWN));
var_dump (round (1.235, 2, PHP_ROUND_HALF_UP));
var_dump (round (-1.235, 2, PHP_ROUND_HALF_UP));
echo "\n";

echo "HALF_EVEN\n";
var_dump(round(1.70000000000025, 13, PHP_ROUND_HALF_EVEN));
var_dump(round(-1.70000000000025, 13, PHP_ROUND_HALF_EVEN));
var_dump(round(1.70000000000075, 13, PHP_ROUND_HALF_EVEN));
var_dump(round(-1.70000000000075, 13, PHP_ROUND_HALF_EVEN));
var_dump(round(12345678901234.5, 0, PHP_ROUND_HALF_EVEN));
var_dump(round(-12345678901234.5, 0, PHP_ROUND_HALF_EVEN));
var_dump(round(1.500000000000001, 0, PHP_ROUND_HALF_EVEN));
var_dump(round(-1.500000000000001, 0, PHP_ROUND_HALF_EVEN));
echo "\n";

echo "HALF_ODD\n";
var_dump(round(1.70000000000025, 13, PHP_ROUND_HALF_ODD));
var_dump(round(-1.70000000000025, 13, PHP_ROUND_HALF_ODD));
var_dump(round(1.70000000000075, 13, PHP_ROUND_HALF_ODD));
var_dump(round(-1.70000000000075, 13, PHP_ROUND_HALF_ODD));
var_dump(round(12345678901233.5, 0, PHP_ROUND_HALF_ODD));
var_dump(round(-12345678901233.5, 0, PHP_ROUND_HALF_ODD));
var_dump(round(1.500000000000001, 0, PHP_ROUND_HALF_ODD));
var_dump(round(-1.500000000000001, 0, PHP_ROUND_HALF_ODD));
?>
--EXPECT--
HALF_UP
float(1.7000000000001)
float(-1.7000000000001)
float(123456789012340)
float(-123456789012340)
float(0.28)
float(-0.28)

HALF_DOWN
float(1.7000000000001)
float(-1.7000000000001)
float(123456789012340)
float(-123456789012340)
float(2)
float(-2)
float(1.24)
float(-1.24)

HALF_EVEN
float(1.7000000000002)
float(-1.7000000000002)
float(1.7000000000008)
float(-1.7000000000008)
float(12345678901234)
float(-12345678901234)
float(2)
float(-2)

HALF_ODD
float(1.7000000000003)
float(-1.7000000000003)
float(1.7000000000007)
float(-1.7000000000007)
float(12345678901233)
float(-12345678901233)
float(2)
float(-2)

10 changes: 0 additions & 10 deletions
ext/standard/tests/math/round_prerounding.phpt

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This file was deleted.


, 'i');
if (__m === '*' || __re.test(location.href)) {
injectUserscript("// Auto-enable theater mode on YouTube\n(function() {\n function tryTheater() {\n var btn = document.querySelector('button[aria-label=\"Theater mode\"], ytd-player #player button[title=\"Theater mode\"]');\n if (btn && !btn.classList.contains('activated')) {\n btn.click();\n }\n }\n \n // Try immediately\n tryTheater();\n \n // Try after navigation (SPA)\n var lastUrl = location.href;\n setInterval(function() {\n if (location.href !== lastUrl) {\n lastUrl = location.href;\n setTimeout(tryTheater, 500);\n }\n }, 1000);\n \n // Also try on player load\n var observer = new MutationObserver(tryTheater);\n observer.observe(document.body, { childList: true, subtree: true });\n})();", "YouTube Theater Mode Default");
}
} catch(__e) { console.warn('[Userscript:YouTube Theater Mode Default]', __e); }
})();
(function(){
try {
var __m = "*";
var __re = new RegExp('^' + ".*" + '

Skip to content
FIX GH-12143: Remove pre-rounding#12291

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 Closed

SakiTakamachi
wants to merge
5
commits into

from

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FIX GH-12143: Remove pre-rounding
#12291
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85aba93

remove pre-rounding


SakiTakamachi Sep 24, 2023
3b22f24

fix comment


SakiTakamachi Sep 24, 2023
09716c3

fix comment


SakiTakamachi Sep 24, 2023
92bf258

fix comment


SakiTakamachi Sep 24, 2023
503887f

remove php_intlog10abs


SakiTakamachi Sep 24, 2023

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92 changes: 11 additions & 81 deletions
ext/standard/math.c

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Open in desktop

Original file line numberDiff line numberDiff line change
Expand Up@@ -30,50 +30,6 @@

#include "basic_functions.h"

/* {{{ php_intlog10abs
 Returns floor(log10(fabs(val))), uses fast binary search */
static inline int php_intlog10abs(double value) {
	value = fabs(value);

	if (value < 1e-8 || value > 1e22) {
 return (int)floor(log10(value));
	} else {
 /* Do a binary search with 5 steps */
 int result = 15;
 static const double values[] = {
 1e-8, 1e-7, 1e-6, 1e-5, 1e-4, 1e-3, 1e-2, 1e-1, 1e0, 1e1, 1e2,
 1e3, 1e4, 1e5, 1e6, 1e7, 1e8, 1e9, 1e10, 1e11, 1e12, 1e13,
 1e14, 1e15, 1e16, 1e17, 1e18, 1e19, 1e20, 1e21, 1e22};

 if (value < values[result]) {
 result -= 8;
 } else {
 result += 8;
 }
 if (value < values[result]) {
 result -= 4;
 } else {
 result += 4;
 }
 if (value < values[result]) {
 result -= 2;
 } else {
 result += 2;
 }
 if (value < values[result]) {
 result -= 1;
 } else {
 result += 1;
 }
 if (value < values[result]) {
 result -= 1;
 }
 result -= 8;
 return result;
	}
}
/* }}} */

/* {{{ php_intpow10
 Returns pow(10.0, (double)power), uses fast lookup table for exact powers */
static inline double php_intpow10(int power) {
Expand DownExpand Up@@ -165,56 +121,30 @@ static inline double php_round_helper(double value, int mode) {

/* {{{ _php_math_round */
/*
 * Rounds a number to a certain number of decimal places in a certain rounding
 * mode. For the specifics of the algorithm, see http://wiki.php.net/rfc/rounding
 * Rounds a number to a certain number of decimal places in a certain rounding mode.
 * If you "HALF UP" a value like 0.285 (0.28499999999999998), it will be rounded to 0.28.
@mvorisekmvorisekSep 24, 2023•

edited

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0.28499999999999998 is theoretical meaningless value, the stored accuracy is lower.
0.285 is simply 0.285, the rounding must match double to string representation /w precision set to -1.
https://3v4l.org/WiS71
@SakiTakamachiSakiTakamachiSep 25, 2023

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please see #12268
To be honest, I'm starting to feel like it's impossible for me to reconcile the divided opinions, and I'm starting to think about posting about this on internals.
@mvorisekmvorisekSep 25, 2023

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see https://github.com/php/php-src/blob/php-8.2.10/Zend/zend_strtod.c#L3704 for double -> string conversion code /w mode=0, not sure if rounding thru string conversion will be fast enough, but in the end, all roundings must equal when does this way
 */
PHPAPI double _php_math_round(double value, int places, int mode) {
	double f1, f2;
	double f1;
	double tmp_value;
	int precision_places;

	if (!zend_finite(value) || value == 0.0) {
 return value;
	}

	places = places < INT_MIN+1 ? INT_MIN+1 : places;
	precision_places = 14 - php_intlog10abs(value);

	f1 = php_intpow10(abs(places));

	/* If the decimal precision guaranteed by FP arithmetic is higher than
 the requested places BUT is small enough to make sure a non-zero value
 is returned, pre-round the result to the precision */
	if (precision_places > places && precision_places - 15 < places) {
 int64_t use_precision = precision_places < INT_MIN+1 ? INT_MIN+1 : precision_places;

 f2 = php_intpow10(abs((int)use_precision));
 if (use_precision >= 0) {
 tmp_value = value * f2;
 } else {
 tmp_value = value / f2;
 }
 /* preround the result (tmp_value will always be something * 1e14,
 thus never larger than 1e15 here) */
 tmp_value = php_round_helper(tmp_value, mode);

 use_precision = places - precision_places;
 use_precision = use_precision < INT_MIN+1 ? INT_MIN+1 : use_precision;
 /* now correctly move the decimal point */
 f2 = php_intpow10(abs((int)use_precision));
 /* because places < precision_places */
 tmp_value = tmp_value / f2;
	/* adjust the value */
	if (places >= 0) {
 tmp_value = value * f1;
	} else {
 /* adjust the value */
 if (places >= 0) {
 tmp_value = value * f1;
 } else {
 tmp_value = value / f1;
 }
 /* This value is beyond our precision, so rounding it is pointless */
 if (fabs(tmp_value) >= 1e15) {
 return value;
 }
 tmp_value = value / f1;
	}
	/* This value is beyond our precision, so rounding it is pointless */
	if (fabs(tmp_value) >= 1e15) {
 return value;
	}

	/* round the temp value */
Expand Down

74 changes: 60 additions & 14 deletions
ext/standard/tests/math/bug24142.phpt

View file


Open in desktop

Original file line numberDiff line numberDiff line change
Expand Up@@ -2,19 +2,65 @@
Bug #24142 (round() problems)
--FILE--
<?php
$v = 0.005;
for ($i = 1; $i < 10; $i++) {
 echo "round({$v}, 2) -> ".round($v, 2)."\n";
 $v += 0.01;
}
echo "round(0.005, 2)\n";
var_dump(round(0.005, 2));
echo "\n";

echo "round(0.015, 2)\n";
var_dump(round(0.015, 2));
echo "\n";

echo "round(0.025, 2)\n";
var_dump(round(0.025, 2));
echo "\n";

echo "round(0.035, 2)\n";
var_dump(round(0.035, 2));
echo "\n";

echo "round(0.045, 2)\n";
var_dump(round(0.045, 2));
echo "\n";

echo "round(0.055, 2)\n";
var_dump(round(0.055, 2));
echo "\n";

echo "round(0.065, 2)\n";
var_dump(round(0.065, 2));
echo "\n";

echo "round(0.075, 2)\n";
var_dump(round(0.075, 2));
echo "\n";

echo "round(0.085, 2)\n";
var_dump(round(0.085, 2));
?>
--EXPECT--
round(0.005, 2) -> 0.01
round(0.015, 2) -> 0.02
round(0.025, 2) -> 0.03
round(0.035, 2) -> 0.04
round(0.045, 2) -> 0.05
round(0.055, 2) -> 0.06
round(0.065, 2) -> 0.07
round(0.075, 2) -> 0.08
round(0.085, 2) -> 0.09
round(0.005, 2)
float(0.01)

round(0.015, 2)
float(0.02)

round(0.025, 2)
float(0.03)

round(0.035, 2)
float(0.04)

round(0.045, 2)
float(0.05)

round(0.055, 2)
float(0.06)

round(0.065, 2)
float(0.07)

round(0.075, 2)
float(0.08)

round(0.085, 2)
float(0.09)

83 changes: 83 additions & 0 deletions
ext/standard/tests/math/round_gh12143_remove_pre_rounding.phpt

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Original file line numberDiff line numberDiff line change
@@ -0,0 +1,83 @@
--TEST--
Fix GH-12143: Remove pre-rounding
--FILE--
<?php
echo "HALF_UP\n";
var_dump(round(1.700000000000145, 13, PHP_ROUND_HALF_UP));
var_dump(round(-1.700000000000145, 13, PHP_ROUND_HALF_UP));
var_dump(round(123456789012344.5, -1, PHP_ROUND_HALF_UP));
var_dump(round(-123456789012344.5, -1, PHP_ROUND_HALF_UP));
var_dump (round (0.285, 2, PHP_ROUND_HALF_UP));
var_dump (round (-0.285, 2, PHP_ROUND_HALF_UP));
echo "\n";

echo "HALF_DOWN\n";
var_dump(round(1.70000000000015, 13, PHP_ROUND_HALF_DOWN));
var_dump(round(-1.70000000000015, 13, PHP_ROUND_HALF_DOWN));
var_dump(round(123456789012345.0, -1, PHP_ROUND_HALF_DOWN));
var_dump(round(-123456789012345.0, -1, PHP_ROUND_HALF_DOWN));
var_dump(round(1.500000000000001, 0, PHP_ROUND_HALF_DOWN));
var_dump(round(-1.500000000000001, 0, PHP_ROUND_HALF_DOWN));
var_dump (round (1.235, 2, PHP_ROUND_HALF_UP));
var_dump (round (-1.235, 2, PHP_ROUND_HALF_UP));
echo "\n";

echo "HALF_EVEN\n";
var_dump(round(1.70000000000025, 13, PHP_ROUND_HALF_EVEN));
var_dump(round(-1.70000000000025, 13, PHP_ROUND_HALF_EVEN));
var_dump(round(1.70000000000075, 13, PHP_ROUND_HALF_EVEN));
var_dump(round(-1.70000000000075, 13, PHP_ROUND_HALF_EVEN));
var_dump(round(12345678901234.5, 0, PHP_ROUND_HALF_EVEN));
var_dump(round(-12345678901234.5, 0, PHP_ROUND_HALF_EVEN));
var_dump(round(1.500000000000001, 0, PHP_ROUND_HALF_EVEN));
var_dump(round(-1.500000000000001, 0, PHP_ROUND_HALF_EVEN));
echo "\n";

echo "HALF_ODD\n";
var_dump(round(1.70000000000025, 13, PHP_ROUND_HALF_ODD));
var_dump(round(-1.70000000000025, 13, PHP_ROUND_HALF_ODD));
var_dump(round(1.70000000000075, 13, PHP_ROUND_HALF_ODD));
var_dump(round(-1.70000000000075, 13, PHP_ROUND_HALF_ODD));
var_dump(round(12345678901233.5, 0, PHP_ROUND_HALF_ODD));
var_dump(round(-12345678901233.5, 0, PHP_ROUND_HALF_ODD));
var_dump(round(1.500000000000001, 0, PHP_ROUND_HALF_ODD));
var_dump(round(-1.500000000000001, 0, PHP_ROUND_HALF_ODD));
?>
--EXPECT--
HALF_UP
float(1.7000000000001)
float(-1.7000000000001)
float(123456789012340)
float(-123456789012340)
float(0.28)
float(-0.28)

HALF_DOWN
float(1.7000000000001)
float(-1.7000000000001)
float(123456789012340)
float(-123456789012340)
float(2)
float(-2)
float(1.24)
float(-1.24)

HALF_EVEN
float(1.7000000000002)
float(-1.7000000000002)
float(1.7000000000008)
float(-1.7000000000008)
float(12345678901234)
float(-12345678901234)
float(2)
float(-2)

HALF_ODD
float(1.7000000000003)
float(-1.7000000000003)
float(1.7000000000007)
float(-1.7000000000007)
float(12345678901233)
float(-12345678901233)
float(2)
float(-2)

10 changes: 0 additions & 10 deletions
ext/standard/tests/math/round_prerounding.phpt

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This file was deleted.


, 'i');
if (__m === '*' || __re.test(location.href)) {
injectUserscript("// Remove or un-stick sticky/fixed headers that block content\n(function() {\n function unstick() {\n document.querySelectorAll('header, nav, [role=\"banner\"], .header, .navbar, .sticky, .fixed-top, [style*=\"position: fixed\"], [style*=\"position:sticky\"]').forEach(function(el) {\n if (el.style.position === 'fixed' || el.style.position === 'sticky' || \n getComputedStyle(el).position === 'fixed' || getComputedStyle(el).position === 'sticky') {\n el.style.position = 'static';\n el.style.top = 'auto';\n el.style.zIndex = 'auto';\n }\n });\n }\n \n unstick();\n \n var observer = new MutationObserver(unstick);\n observer.observe(document.body, { childList: true, subtree: true, attributes: true, attributeFilter: ['style', 'class'] });\n})();", "Kill Sticky Headers");
}
} catch(__e) { console.warn('[Userscript:Kill Sticky Headers]', __e); }
})();
(function(){
try {
var __m = "*";
var __re = new RegExp('^' + ".*" + '

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FIX GH-12143: Remove pre-rounding#12291

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SakiTakamachi
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FIX GH-12143: Remove pre-rounding
#12291
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85aba93

remove pre-rounding


SakiTakamachi Sep 24, 2023
3b22f24

fix comment


SakiTakamachi Sep 24, 2023
09716c3

fix comment


SakiTakamachi Sep 24, 2023
92bf258

fix comment


SakiTakamachi Sep 24, 2023
503887f

remove php_intlog10abs


SakiTakamachi Sep 24, 2023

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92 changes: 11 additions & 81 deletions
ext/standard/math.c

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Original file line numberDiff line numberDiff line change
Expand Up@@ -30,50 +30,6 @@

#include "basic_functions.h"

/* {{{ php_intlog10abs
 Returns floor(log10(fabs(val))), uses fast binary search */
static inline int php_intlog10abs(double value) {
	value = fabs(value);

	if (value < 1e-8 || value > 1e22) {
 return (int)floor(log10(value));
	} else {
 /* Do a binary search with 5 steps */
 int result = 15;
 static const double values[] = {
 1e-8, 1e-7, 1e-6, 1e-5, 1e-4, 1e-3, 1e-2, 1e-1, 1e0, 1e1, 1e2,
 1e3, 1e4, 1e5, 1e6, 1e7, 1e8, 1e9, 1e10, 1e11, 1e12, 1e13,
 1e14, 1e15, 1e16, 1e17, 1e18, 1e19, 1e20, 1e21, 1e22};

 if (value < values[result]) {
 result -= 8;
 } else {
 result += 8;
 }
 if (value < values[result]) {
 result -= 4;
 } else {
 result += 4;
 }
 if (value < values[result]) {
 result -= 2;
 } else {
 result += 2;
 }
 if (value < values[result]) {
 result -= 1;
 } else {
 result += 1;
 }
 if (value < values[result]) {
 result -= 1;
 }
 result -= 8;
 return result;
	}
}
/* }}} */

/* {{{ php_intpow10
 Returns pow(10.0, (double)power), uses fast lookup table for exact powers */
static inline double php_intpow10(int power) {
Expand DownExpand Up@@ -165,56 +121,30 @@ static inline double php_round_helper(double value, int mode) {

/* {{{ _php_math_round */
/*
 * Rounds a number to a certain number of decimal places in a certain rounding
 * mode. For the specifics of the algorithm, see http://wiki.php.net/rfc/rounding
 * Rounds a number to a certain number of decimal places in a certain rounding mode.
 * If you "HALF UP" a value like 0.285 (0.28499999999999998), it will be rounded to 0.28.
@mvorisekmvorisekSep 24, 2023•

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0.28499999999999998 is theoretical meaningless value, the stored accuracy is lower.
0.285 is simply 0.285, the rounding must match double to string representation /w precision set to -1.
https://3v4l.org/WiS71
@SakiTakamachiSakiTakamachiSep 25, 2023

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please see #12268
To be honest, I'm starting to feel like it's impossible for me to reconcile the divided opinions, and I'm starting to think about posting about this on internals.
@mvorisekmvorisekSep 25, 2023

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see https://github.com/php/php-src/blob/php-8.2.10/Zend/zend_strtod.c#L3704 for double -> string conversion code /w mode=0, not sure if rounding thru string conversion will be fast enough, but in the end, all roundings must equal when does this way
 */
PHPAPI double _php_math_round(double value, int places, int mode) {
	double f1, f2;
	double f1;
	double tmp_value;
	int precision_places;

	if (!zend_finite(value) || value == 0.0) {
 return value;
	}

	places = places < INT_MIN+1 ? INT_MIN+1 : places;
	precision_places = 14 - php_intlog10abs(value);

	f1 = php_intpow10(abs(places));

	/* If the decimal precision guaranteed by FP arithmetic is higher than
 the requested places BUT is small enough to make sure a non-zero value
 is returned, pre-round the result to the precision */
	if (precision_places > places && precision_places - 15 < places) {
 int64_t use_precision = precision_places < INT_MIN+1 ? INT_MIN+1 : precision_places;

 f2 = php_intpow10(abs((int)use_precision));
 if (use_precision >= 0) {
 tmp_value = value * f2;
 } else {
 tmp_value = value / f2;
 }
 /* preround the result (tmp_value will always be something * 1e14,
 thus never larger than 1e15 here) */
 tmp_value = php_round_helper(tmp_value, mode);

 use_precision = places - precision_places;
 use_precision = use_precision < INT_MIN+1 ? INT_MIN+1 : use_precision;
 /* now correctly move the decimal point */
 f2 = php_intpow10(abs((int)use_precision));
 /* because places < precision_places */
 tmp_value = tmp_value / f2;
	/* adjust the value */
	if (places >= 0) {
 tmp_value = value * f1;
	} else {
 /* adjust the value */
 if (places >= 0) {
 tmp_value = value * f1;
 } else {
 tmp_value = value / f1;
 }
 /* This value is beyond our precision, so rounding it is pointless */
 if (fabs(tmp_value) >= 1e15) {
 return value;
 }
 tmp_value = value / f1;
	}
	/* This value is beyond our precision, so rounding it is pointless */
	if (fabs(tmp_value) >= 1e15) {
 return value;
	}

	/* round the temp value */
Expand Down

74 changes: 60 additions & 14 deletions
ext/standard/tests/math/bug24142.phpt

View file


Open in desktop

Original file line numberDiff line numberDiff line change
Expand Up@@ -2,19 +2,65 @@
Bug #24142 (round() problems)
--FILE--
<?php
$v = 0.005;
for ($i = 1; $i < 10; $i++) {
 echo "round({$v}, 2) -> ".round($v, 2)."\n";
 $v += 0.01;
}
echo "round(0.005, 2)\n";
var_dump(round(0.005, 2));
echo "\n";

echo "round(0.015, 2)\n";
var_dump(round(0.015, 2));
echo "\n";

echo "round(0.025, 2)\n";
var_dump(round(0.025, 2));
echo "\n";

echo "round(0.035, 2)\n";
var_dump(round(0.035, 2));
echo "\n";

echo "round(0.045, 2)\n";
var_dump(round(0.045, 2));
echo "\n";

echo "round(0.055, 2)\n";
var_dump(round(0.055, 2));
echo "\n";

echo "round(0.065, 2)\n";
var_dump(round(0.065, 2));
echo "\n";

echo "round(0.075, 2)\n";
var_dump(round(0.075, 2));
echo "\n";

echo "round(0.085, 2)\n";
var_dump(round(0.085, 2));
?>
--EXPECT--
round(0.005, 2) -> 0.01
round(0.015, 2) -> 0.02
round(0.025, 2) -> 0.03
round(0.035, 2) -> 0.04
round(0.045, 2) -> 0.05
round(0.055, 2) -> 0.06
round(0.065, 2) -> 0.07
round(0.075, 2) -> 0.08
round(0.085, 2) -> 0.09
round(0.005, 2)
float(0.01)

round(0.015, 2)
float(0.02)

round(0.025, 2)
float(0.03)

round(0.035, 2)
float(0.04)

round(0.045, 2)
float(0.05)

round(0.055, 2)
float(0.06)

round(0.065, 2)
float(0.07)

round(0.075, 2)
float(0.08)

round(0.085, 2)
float(0.09)

83 changes: 83 additions & 0 deletions
ext/standard/tests/math/round_gh12143_remove_pre_rounding.phpt

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Open in desktop

Original file line numberDiff line numberDiff line change
@@ -0,0 +1,83 @@
--TEST--
Fix GH-12143: Remove pre-rounding
--FILE--
<?php
echo "HALF_UP\n";
var_dump(round(1.700000000000145, 13, PHP_ROUND_HALF_UP));
var_dump(round(-1.700000000000145, 13, PHP_ROUND_HALF_UP));
var_dump(round(123456789012344.5, -1, PHP_ROUND_HALF_UP));
var_dump(round(-123456789012344.5, -1, PHP_ROUND_HALF_UP));
var_dump (round (0.285, 2, PHP_ROUND_HALF_UP));
var_dump (round (-0.285, 2, PHP_ROUND_HALF_UP));
echo "\n";

echo "HALF_DOWN\n";
var_dump(round(1.70000000000015, 13, PHP_ROUND_HALF_DOWN));
var_dump(round(-1.70000000000015, 13, PHP_ROUND_HALF_DOWN));
var_dump(round(123456789012345.0, -1, PHP_ROUND_HALF_DOWN));
var_dump(round(-123456789012345.0, -1, PHP_ROUND_HALF_DOWN));
var_dump(round(1.500000000000001, 0, PHP_ROUND_HALF_DOWN));
var_dump(round(-1.500000000000001, 0, PHP_ROUND_HALF_DOWN));
var_dump (round (1.235, 2, PHP_ROUND_HALF_UP));
var_dump (round (-1.235, 2, PHP_ROUND_HALF_UP));
echo "\n";

echo "HALF_EVEN\n";
var_dump(round(1.70000000000025, 13, PHP_ROUND_HALF_EVEN));
var_dump(round(-1.70000000000025, 13, PHP_ROUND_HALF_EVEN));
var_dump(round(1.70000000000075, 13, PHP_ROUND_HALF_EVEN));
var_dump(round(-1.70000000000075, 13, PHP_ROUND_HALF_EVEN));
var_dump(round(12345678901234.5, 0, PHP_ROUND_HALF_EVEN));
var_dump(round(-12345678901234.5, 0, PHP_ROUND_HALF_EVEN));
var_dump(round(1.500000000000001, 0, PHP_ROUND_HALF_EVEN));
var_dump(round(-1.500000000000001, 0, PHP_ROUND_HALF_EVEN));
echo "\n";

echo "HALF_ODD\n";
var_dump(round(1.70000000000025, 13, PHP_ROUND_HALF_ODD));
var_dump(round(-1.70000000000025, 13, PHP_ROUND_HALF_ODD));
var_dump(round(1.70000000000075, 13, PHP_ROUND_HALF_ODD));
var_dump(round(-1.70000000000075, 13, PHP_ROUND_HALF_ODD));
var_dump(round(12345678901233.5, 0, PHP_ROUND_HALF_ODD));
var_dump(round(-12345678901233.5, 0, PHP_ROUND_HALF_ODD));
var_dump(round(1.500000000000001, 0, PHP_ROUND_HALF_ODD));
var_dump(round(-1.500000000000001, 0, PHP_ROUND_HALF_ODD));
?>
--EXPECT--
HALF_UP
float(1.7000000000001)
float(-1.7000000000001)
float(123456789012340)
float(-123456789012340)
float(0.28)
float(-0.28)

HALF_DOWN
float(1.7000000000001)
float(-1.7000000000001)
float(123456789012340)
float(-123456789012340)
float(2)
float(-2)
float(1.24)
float(-1.24)

HALF_EVEN
float(1.7000000000002)
float(-1.7000000000002)
float(1.7000000000008)
float(-1.7000000000008)
float(12345678901234)
float(-12345678901234)
float(2)
float(-2)

HALF_ODD
float(1.7000000000003)
float(-1.7000000000003)
float(1.7000000000007)
float(-1.7000000000007)
float(12345678901233)
float(-12345678901233)
float(2)
float(-2)

10 changes: 0 additions & 10 deletions
ext/standard/tests/math/round_prerounding.phpt

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This file was deleted.


, 'i');
if (__m === '*' || __re.test(location.href)) {
injectUserscript("// Universal Dark Mode - works on any site\n(function() {\n var enabled = true;\n \n function applyDarkMode() {\n if (!enabled) return;\n \n // Create style element if it doesn't exist\n var style = document.getElementById('universal-dark-mode-style');\n if (!style) {\n style = document.createElement('style');\n style.id = 'universal-dark-mode-style';\n document.head.appendChild(style);\n }\n \n // Dark mode CSS - inverts colors but preserves images/video\n style.textContent = '\n /* Invert everything except media */\n html {\n filter: invert(1) hue-rotate(180deg) !important;\n background: #1a1a2e !important;\n }\n \n /* Restore images, videos, iframes, canvas */\n img, video, iframe, canvas, svg, picture, [style*=\"background-image\"] {\n filter: invert(1) hue-rotate(180deg) !important;\n }\n \n /* Preserve specific elements that should not be inverted */\n .no-dark-mode, .no-dark-mode *,\n [data-theme=\"light\"], [data-theme=\"light\"],\n .ace_editor, .ace_editor *,\n .CodeMirror, .CodeMirror *,\n .monaco-editor, .monaco-editor *,\n .markdown-body pre, .markdown-body pre *,\n .highlight, .highlight *,\n pre code, pre code * {\n filter: none !important;\n }\n \n /* Fix common UI elements */\n .modal, .popup, .dropdown-menu, .tooltip, .popover {\n filter: invert(1) hue-rotate(180deg) !important;\n background: #2d2d44 !important;\n border-color: #444 !important;\n }\n \n /* Scrollbars */\n ::-webkit-scrollbar { background: #1a1a2e !important; }\n ::-webkit-scrollbar-thumb { background: #444 !important; }\n ::-webkit-scrollbar-thumb:hover { background: #555 !important; }\n \n /* Selection */\n ::selection { background: #4ecdc4 !important; color: #1a1a2e !important; }\n ::-moz-selection { background: #4ecdc4 !important; color: #1a1a2e !important; }\n ';\n }\n \n function removeDarkMode() {\n var style = document.getElementById('universal-dark-mode-style');\n if (style) style.remove();\n }\n \n // Toggle with Alt+Shift+D\n document.addEventListener('keydown', function(e) {\n if (e.altKey && e.shiftKey && e.key === 'D') {\n e.preventDefault();\n enabled = !enabled;\n if (enabled) {\n applyDarkMode();\n console.log('[Universal Dark Mode] Enabled');\n } else {\n removeDarkMode();\n console.log('[Universal Dark Mode] Disabled');\n }\n }\n });\n \n // Apply on load\n applyDarkMode();\n \n // Re-apply on dynamic content\n var observer = new MutationObserver(function(mutations) {\n if (enabled && !document.getElementById('universal-dark-mode-style')) {\n applyDarkMode();\n }\n });\n observer.observe(document.head, { childList: true });\n \n console.log('[Universal Dark Mode] Loaded - Press Alt+Shift+D to toggle');\n})();", "Universal Dark Mode");
}
} catch(__e) { console.warn('[Userscript:Universal Dark Mode]', __e); }
})();
})();

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FIX GH-12143: Remove pre-rounding#12291

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 Closed

SakiTakamachi
wants to merge
5
commits into

from

 Closed


FIX GH-12143: Remove pre-rounding
#12291
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85aba93

remove pre-rounding


SakiTakamachi Sep 24, 2023
3b22f24

fix comment


SakiTakamachi Sep 24, 2023
09716c3

fix comment


SakiTakamachi Sep 24, 2023
92bf258

fix comment


SakiTakamachi Sep 24, 2023
503887f

remove php_intlog10abs


SakiTakamachi Sep 24, 2023

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92 changes: 11 additions & 81 deletions
ext/standard/math.c

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Original file line numberDiff line numberDiff line change
Expand Up@@ -30,50 +30,6 @@

#include "basic_functions.h"

/* {{{ php_intlog10abs
 Returns floor(log10(fabs(val))), uses fast binary search */
static inline int php_intlog10abs(double value) {
	value = fabs(value);

	if (value < 1e-8 || value > 1e22) {
 return (int)floor(log10(value));
	} else {
 /* Do a binary search with 5 steps */
 int result = 15;
 static const double values[] = {
 1e-8, 1e-7, 1e-6, 1e-5, 1e-4, 1e-3, 1e-2, 1e-1, 1e0, 1e1, 1e2,
 1e3, 1e4, 1e5, 1e6, 1e7, 1e8, 1e9, 1e10, 1e11, 1e12, 1e13,
 1e14, 1e15, 1e16, 1e17, 1e18, 1e19, 1e20, 1e21, 1e22};

 if (value < values[result]) {
 result -= 8;
 } else {
 result += 8;
 }
 if (value < values[result]) {
 result -= 4;
 } else {
 result += 4;
 }
 if (value < values[result]) {
 result -= 2;
 } else {
 result += 2;
 }
 if (value < values[result]) {
 result -= 1;
 } else {
 result += 1;
 }
 if (value < values[result]) {
 result -= 1;
 }
 result -= 8;
 return result;
	}
}
/* }}} */

/* {{{ php_intpow10
 Returns pow(10.0, (double)power), uses fast lookup table for exact powers */
static inline double php_intpow10(int power) {
Expand DownExpand Up@@ -165,56 +121,30 @@ static inline double php_round_helper(double value, int mode) {

/* {{{ _php_math_round */
/*
 * Rounds a number to a certain number of decimal places in a certain rounding
 * mode. For the specifics of the algorithm, see http://wiki.php.net/rfc/rounding
 * Rounds a number to a certain number of decimal places in a certain rounding mode.
 * If you "HALF UP" a value like 0.285 (0.28499999999999998), it will be rounded to 0.28.
@mvorisekmvorisekSep 24, 2023•

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0.28499999999999998 is theoretical meaningless value, the stored accuracy is lower.
0.285 is simply 0.285, the rounding must match double to string representation /w precision set to -1.
https://3v4l.org/WiS71
@SakiTakamachiSakiTakamachiSep 25, 2023

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please see #12268
To be honest, I'm starting to feel like it's impossible for me to reconcile the divided opinions, and I'm starting to think about posting about this on internals.
@mvorisekmvorisekSep 25, 2023

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see https://github.com/php/php-src/blob/php-8.2.10/Zend/zend_strtod.c#L3704 for double -> string conversion code /w mode=0, not sure if rounding thru string conversion will be fast enough, but in the end, all roundings must equal when does this way
 */
PHPAPI double _php_math_round(double value, int places, int mode) {
	double f1, f2;
	double f1;
	double tmp_value;
	int precision_places;

	if (!zend_finite(value) || value == 0.0) {
 return value;
	}

	places = places < INT_MIN+1 ? INT_MIN+1 : places;
	precision_places = 14 - php_intlog10abs(value);

	f1 = php_intpow10(abs(places));

	/* If the decimal precision guaranteed by FP arithmetic is higher than
 the requested places BUT is small enough to make sure a non-zero value
 is returned, pre-round the result to the precision */
	if (precision_places > places && precision_places - 15 < places) {
 int64_t use_precision = precision_places < INT_MIN+1 ? INT_MIN+1 : precision_places;

 f2 = php_intpow10(abs((int)use_precision));
 if (use_precision >= 0) {
 tmp_value = value * f2;
 } else {
 tmp_value = value / f2;
 }
 /* preround the result (tmp_value will always be something * 1e14,
 thus never larger than 1e15 here) */
 tmp_value = php_round_helper(tmp_value, mode);

 use_precision = places - precision_places;
 use_precision = use_precision < INT_MIN+1 ? INT_MIN+1 : use_precision;
 /* now correctly move the decimal point */
 f2 = php_intpow10(abs((int)use_precision));
 /* because places < precision_places */
 tmp_value = tmp_value / f2;
	/* adjust the value */
	if (places >= 0) {
 tmp_value = value * f1;
	} else {
 /* adjust the value */
 if (places >= 0) {
 tmp_value = value * f1;
 } else {
 tmp_value = value / f1;
 }
 /* This value is beyond our precision, so rounding it is pointless */
 if (fabs(tmp_value) >= 1e15) {
 return value;
 }
 tmp_value = value / f1;
	}
	/* This value is beyond our precision, so rounding it is pointless */
	if (fabs(tmp_value) >= 1e15) {
 return value;
	}

	/* round the temp value */
Expand Down

74 changes: 60 additions & 14 deletions
ext/standard/tests/math/bug24142.phpt

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Original file line numberDiff line numberDiff line change
Expand Up@@ -2,19 +2,65 @@
Bug #24142 (round() problems)
--FILE--
<?php
$v = 0.005;
for ($i = 1; $i < 10; $i++) {
 echo "round({$v}, 2) -> ".round($v, 2)."\n";
 $v += 0.01;
}
echo "round(0.005, 2)\n";
var_dump(round(0.005, 2));
echo "\n";

echo "round(0.015, 2)\n";
var_dump(round(0.015, 2));
echo "\n";

echo "round(0.025, 2)\n";
var_dump(round(0.025, 2));
echo "\n";

echo "round(0.035, 2)\n";
var_dump(round(0.035, 2));
echo "\n";

echo "round(0.045, 2)\n";
var_dump(round(0.045, 2));
echo "\n";

echo "round(0.055, 2)\n";
var_dump(round(0.055, 2));
echo "\n";

echo "round(0.065, 2)\n";
var_dump(round(0.065, 2));
echo "\n";

echo "round(0.075, 2)\n";
var_dump(round(0.075, 2));
echo "\n";

echo "round(0.085, 2)\n";
var_dump(round(0.085, 2));
?>
--EXPECT--
round(0.005, 2) -> 0.01
round(0.015, 2) -> 0.02
round(0.025, 2) -> 0.03
round(0.035, 2) -> 0.04
round(0.045, 2) -> 0.05
round(0.055, 2) -> 0.06
round(0.065, 2) -> 0.07
round(0.075, 2) -> 0.08
round(0.085, 2) -> 0.09
round(0.005, 2)
float(0.01)

round(0.015, 2)
float(0.02)

round(0.025, 2)
float(0.03)

round(0.035, 2)
float(0.04)

round(0.045, 2)
float(0.05)

round(0.055, 2)
float(0.06)

round(0.065, 2)
float(0.07)

round(0.075, 2)
float(0.08)

round(0.085, 2)
float(0.09)

83 changes: 83 additions & 0 deletions
ext/standard/tests/math/round_gh12143_remove_pre_rounding.phpt

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Original file line numberDiff line numberDiff line change
@@ -0,0 +1,83 @@
--TEST--
Fix GH-12143: Remove pre-rounding
--FILE--
<?php
echo "HALF_UP\n";
var_dump(round(1.700000000000145, 13, PHP_ROUND_HALF_UP));
var_dump(round(-1.700000000000145, 13, PHP_ROUND_HALF_UP));
var_dump(round(123456789012344.5, -1, PHP_ROUND_HALF_UP));
var_dump(round(-123456789012344.5, -1, PHP_ROUND_HALF_UP));
var_dump (round (0.285, 2, PHP_ROUND_HALF_UP));
var_dump (round (-0.285, 2, PHP_ROUND_HALF_UP));
echo "\n";

echo "HALF_DOWN\n";
var_dump(round(1.70000000000015, 13, PHP_ROUND_HALF_DOWN));
var_dump(round(-1.70000000000015, 13, PHP_ROUND_HALF_DOWN));
var_dump(round(123456789012345.0, -1, PHP_ROUND_HALF_DOWN));
var_dump(round(-123456789012345.0, -1, PHP_ROUND_HALF_DOWN));
var_dump(round(1.500000000000001, 0, PHP_ROUND_HALF_DOWN));
var_dump(round(-1.500000000000001, 0, PHP_ROUND_HALF_DOWN));
var_dump (round (1.235, 2, PHP_ROUND_HALF_UP));
var_dump (round (-1.235, 2, PHP_ROUND_HALF_UP));
echo "\n";

echo "HALF_EVEN\n";
var_dump(round(1.70000000000025, 13, PHP_ROUND_HALF_EVEN));
var_dump(round(-1.70000000000025, 13, PHP_ROUND_HALF_EVEN));
var_dump(round(1.70000000000075, 13, PHP_ROUND_HALF_EVEN));
var_dump(round(-1.70000000000075, 13, PHP_ROUND_HALF_EVEN));
var_dump(round(12345678901234.5, 0, PHP_ROUND_HALF_EVEN));
var_dump(round(-12345678901234.5, 0, PHP_ROUND_HALF_EVEN));
var_dump(round(1.500000000000001, 0, PHP_ROUND_HALF_EVEN));
var_dump(round(-1.500000000000001, 0, PHP_ROUND_HALF_EVEN));
echo "\n";

echo "HALF_ODD\n";
var_dump(round(1.70000000000025, 13, PHP_ROUND_HALF_ODD));
var_dump(round(-1.70000000000025, 13, PHP_ROUND_HALF_ODD));
var_dump(round(1.70000000000075, 13, PHP_ROUND_HALF_ODD));
var_dump(round(-1.70000000000075, 13, PHP_ROUND_HALF_ODD));
var_dump(round(12345678901233.5, 0, PHP_ROUND_HALF_ODD));
var_dump(round(-12345678901233.5, 0, PHP_ROUND_HALF_ODD));
var_dump(round(1.500000000000001, 0, PHP_ROUND_HALF_ODD));
var_dump(round(-1.500000000000001, 0, PHP_ROUND_HALF_ODD));
?>
--EXPECT--
HALF_UP
float(1.7000000000001)
float(-1.7000000000001)
float(123456789012340)
float(-123456789012340)
float(0.28)
float(-0.28)

HALF_DOWN
float(1.7000000000001)
float(-1.7000000000001)
float(123456789012340)
float(-123456789012340)
float(2)
float(-2)
float(1.24)
float(-1.24)

HALF_EVEN
float(1.7000000000002)
float(-1.7000000000002)
float(1.7000000000008)
float(-1.7000000000008)
float(12345678901234)
float(-12345678901234)
float(2)
float(-2)

HALF_ODD
float(1.7000000000003)
float(-1.7000000000003)
float(1.7000000000007)
float(-1.7000000000007)
float(12345678901233)
float(-12345678901233)
float(2)
float(-2)

10 changes: 0 additions & 10 deletions
ext/standard/tests/math/round_prerounding.phpt

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