Skip to content

Fix UB in IntegralTypedArrayAdaptor::toNativeFromDouble() #179

New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Open
carlsmedstad wants to merge 2 commits into
base: main
Choose a base branch
from
Open

Fix UB in IntegralTypedArrayAdaptor::toNativeFromDouble() #179

Show file tree
Hide file tree
Changes from all commits
Commits
Show all changes
2 commits
Select commit Hold shift + click to select a range
501eadf
Fix UB in IntegralTypedArrayAdaptor::toNativeFromDouble()
carlsmedstad Apr 4, 2026
3f10db7
toInt32: add x86_64 fast path using cvttsd2si
carlsmedstad Apr 4, 2026
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
6 changes: 6 additions & 0 deletions Source/JavaScriptCore/runtime/MathCommon.h
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -182,6 +182,12 @@ ALWAYS_INLINE int32_t toInt32(double number)
int32_t result = 0;
__asm__ ("fjcvtzs %w0, %d1" : "=r" (result) : "w" (number) : "cc");
return result;
#elif CPU(X86_64) && COMPILER(GCC_COMPATIBLE)
int32_t result;
__asm__ ("cvttsd2si %1, %0" : "=r" (result) : "x" (number));
if (static_cast<double>(result) != number)
return toIntImpl<int32_t>(number);
return result;
#else
return toIntImpl<int32_t>(number);
#endif
Expand Down
7 changes: 0 additions & 7 deletions Source/JavaScriptCore/runtime/TypedArrayAdaptors.h
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -68,14 +68,7 @@ struct IntegralTypedArrayAdaptor {

static Type toNativeFromDouble(double value)
{
#if HAVE(FJCVTZS_INSTRUCTION)
return static_cast<Type>(toInt32(value));
#else
int32_t result = static_cast<int32_t>(value);
if (static_cast<double>(result) != value)
result = toInt32(value);
return static_cast<Type>(result);
#endif
}

static constexpr Type toNativeFromUndefined()
Expand Down