Attachment 339711 Details for Bug 185374 – Patch

[patch] Patch

bug-185374-20180507195434.patch (text/plain), 5.46 KB, created by Yusuke Suzuki on 2018-05-07 03:54:35 PDT

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Creator: Yusuke Suzuki

Created: 2018-05-07 03:54:35 PDT

Size: 5.46 KB

patch

obsolete

>Subversion Revision: 231404
>diff --git a/Source/JavaScriptCore/ChangeLog b/Source/JavaScriptCore/ChangeLog
>index fb2176fa3b51d9f8651b978d2fc78ae7bba88687..e9436a155167dbe95a9a7e859f4286e31cf5268e 100644
>--- a/Source/JavaScriptCore/ChangeLog
>+++ b/Source/JavaScriptCore/ChangeLog
>@@ -1,3 +1,29 @@
>+2018-05-07  Yusuke Suzuki  <utatane.tea@gmail.com>
>+
>+        [BigInt] Simplifying JSBigInt by using bool addition
>+        https://bugs.webkit.org/show_bug.cgi?id=185374
>+
>+        Reviewed by NOBODY (OOPS!).
>+
>+        Since using TWO_DIGIT does not produce good code, we remove this part from digitAdd and digitSub.
>+        Just adding overflow flag to carry/borrow produces setb + add in x86.
>+
>+        Also we annotate small helper functions and accessors with `inline` not to call these functions
>+        inside internalMultiplyAdd loop.
>+
>+        * runtime/JSBigInt.cpp:
>+        (JSC::JSBigInt::isZero):
>+        (JSC::JSBigInt::inplaceMultiplyAdd):
>+        (JSC::JSBigInt::digitAdd):
>+        (JSC::JSBigInt::digitSub):
>+        (JSC::JSBigInt::digitMul):
>+        (JSC::JSBigInt::digitPow):
>+        (JSC::JSBigInt::digitDiv):
>+        (JSC::JSBigInt::offsetOfData):
>+        (JSC::JSBigInt::dataStorage):
>+        (JSC::JSBigInt::digit):
>+        (JSC::JSBigInt::setDigit):
>+
> 2018-05-06  Yusuke Suzuki  <utatane.tea@gmail.com>
> 
>         [JSC] Remove "using namespace std;" from JSC, bmalloc, WTF
>diff --git a/Source/JavaScriptCore/runtime/JSBigInt.cpp b/Source/JavaScriptCore/runtime/JSBigInt.cpp
>index 3d1e9f183afb09e3cb825aabf2a047980f107993..46c2a6ce57fd337a39da73b80909bfce36231dc8 100644
>--- a/Source/JavaScriptCore/runtime/JSBigInt.cpp
>+++ b/Source/JavaScriptCore/runtime/JSBigInt.cpp
>@@ -230,14 +230,14 @@ String JSBigInt::toString(ExecState& state, int radix)
>     return toStringGeneric(state, this, radix);
> }
> 
>-bool JSBigInt::isZero()
>+inline bool JSBigInt::isZero()
> {
>     ASSERT(length() || !sign());
>     return length() == 0;
> }
> 
> // Multiplies {this} with {factor} and adds {summand} to the result.
>-void JSBigInt::inplaceMultiplyAdd(uintptr_t factor, uintptr_t summand)
>+inline void JSBigInt::inplaceMultiplyAdd(uintptr_t factor, uintptr_t summand)
> {
>     STATIC_ASSERT(sizeof(factor) == sizeof(Digit));
>     STATIC_ASSERT(sizeof(summand) == sizeof(Digit));
>@@ -257,43 +257,24 @@ typedef __uint128_t TwoDigit;
> 
> // {carry} must point to an initialized Digit and will either be incremented
> // by one or left alone.
>-JSBigInt::Digit JSBigInt::digitAdd(Digit a, Digit b, Digit& carry)
>+inline JSBigInt::Digit JSBigInt::digitAdd(Digit a, Digit b, Digit& carry)
> {
>-#if HAVE_TWO_DIGIT
>-    TwoDigit result = static_cast<TwoDigit>(a) + static_cast<TwoDigit>(b);
>-    carry += result >> digitBits;
>-
>-    return static_cast<Digit>(result);
>-#else
>     Digit result = a + b;
>-
>-    if (result < a)
>-        carry += 1;
>-    
>+    carry += static_cast<bool>(result < a);
>     return result;
>-#endif
> }
> 
> // {borrow} must point to an initialized Digit and will either be incremented
> // by one or left alone.
>-JSBigInt::Digit JSBigInt::digitSub(Digit a, Digit b, Digit& borrow)
>+inline JSBigInt::Digit JSBigInt::digitSub(Digit a, Digit b, Digit& borrow)
> {
>-#if HAVE_TWO_DIGIT
>-    TwoDigit result = static_cast<TwoDigit>(a) - static_cast<TwoDigit>(b);
>-    borrow += (result >> digitBits) & 1;
>-    
>-    return static_cast<Digit>(result);
>-#else
>     Digit result = a - b;
>-    if (result > a)
>-        borrow += 1;
>-    
>-    return static_cast<Digit>(result);
>-#endif
>+    borrow += static_cast<bool>(result > a);
>+    return result;
> }
> 
> // Returns the low half of the result. High half is in {high}.
>-JSBigInt::Digit JSBigInt::digitMul(Digit a, Digit b, Digit& high)
>+inline JSBigInt::Digit JSBigInt::digitMul(Digit a, Digit b, Digit& high)
> {
> #if HAVE_TWO_DIGIT
>     TwoDigit result = static_cast<TwoDigit>(a) * static_cast<TwoDigit>(b);
>@@ -332,7 +313,7 @@ JSBigInt::Digit JSBigInt::digitMul(Digit a, Digit b, Digit& high)
> }
> 
> // Raises {base} to the power of {exponent}. Does not check for overflow.
>-JSBigInt::Digit JSBigInt::digitPow(Digit base, Digit exponent)
>+inline JSBigInt::Digit JSBigInt::digitPow(Digit base, Digit exponent)
> {
>     Digit result = 1ull;
>     while (exponent > 0) {
>@@ -348,7 +329,7 @@ JSBigInt::Digit JSBigInt::digitPow(Digit base, Digit exponent)
> 
> // Returns the quotient.
> // quotient = (high << digitBits + low - remainder) / divisor
>-JSBigInt::Digit JSBigInt::digitDiv(Digit high, Digit low, Digit divisor, Digit& remainder)
>+inline JSBigInt::Digit JSBigInt::digitDiv(Digit high, Digit low, Digit divisor, Digit& remainder)
> {
>     ASSERT(high < divisor);
> #if CPU(X86_64) && COMPILER(GCC_OR_CLANG)
>@@ -712,7 +693,7 @@ bool JSBigInt::getPrimitiveNumber(ExecState* state, double& number, JSValue& res
>     return true;
> }
> 
>-size_t JSBigInt::offsetOfData()
>+inline size_t JSBigInt::offsetOfData()
> {
>     return WTF::roundUpToMultipleOf<sizeof(Digit)>(sizeof(JSBigInt));
> }
>@@ -816,18 +797,18 @@ JSBigInt* JSBigInt::parseInt(ExecState* state, VM& vm, CharType* data, int lengt
>     return nullptr;
> }
> 
>-JSBigInt::Digit* JSBigInt::dataStorage()
>+inline JSBigInt::Digit* JSBigInt::dataStorage()
> {
>     return reinterpret_cast<Digit*>(reinterpret_cast<char*>(this) + offsetOfData());
> }
> 
>-JSBigInt::Digit JSBigInt::digit(int n)
>+inline JSBigInt::Digit JSBigInt::digit(int n)
> {
>     ASSERT(n >= 0 && n < length());
>     return dataStorage()[n];
> }
> 
>-void JSBigInt::setDigit(int n, Digit value)
>+inline void JSBigInt::setDigit(int n, Digit value)
> {
>     ASSERT(n >= 0 && n < length());
>     dataStorage()[n] = value;

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achristensen: review+
ews-watchlist: commit-queue-

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Attachments on bug 185374: 339711 | 339719