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Differential D106604

[libc] Raise denormal exception if the libc defines __FE_DENORM.
ClosedPublic

Authored by sivachandra on Jul 22 2021, 3:08 PM.

Details

Reviewers
michaelrj
Commits
rGc698be47ff8c: [libc] Raise denormal exception if the libc defines __FE_DENORM.

Diff Detail

Event Timeline

sivachandra created this revision.Jul 22 2021, 3:08 PM
Herald added a project: Restricted Project. · View Herald TranscriptJul 22 2021, 3:08 PM
Herald added subscribers: libc-commits, ecnelises, tschuett. · View Herald Transcript
sivachandra requested review of this revision.Jul 22 2021, 3:08 PM
michaelrj accepted this revision.Jul 22 2021, 3:11 PM

LGTM

This revision is now accepted and ready to land.Jul 22 2021, 3:11 PM
Harbormaster completed remote builds in B115707: Diff 360991.Jul 22 2021, 5:48 PM
This revision was landed with ongoing or failed builds.Jul 22 2021, 10:42 PM
Closed by commit rGc698be47ff8c: [libc] Raise denormal exception if the libc defines __FE_DENORM. (authored by sivachandra). · Explain Why
This revision was automatically updated to reflect the committed changes.
sivachandra added a commit: rGc698be47ff8c: [libc] Raise denormal exception if the libc defines __FE_DENORM..

Revision Contents

PathSize
libc/
utils/
FPUtil/
x86_64/
48 lines

Diff 361086

libc/utils/FPUtil/x86_64/FEnvImpl.h

Show First 20 Lines • Show All 245 Lines • ▼ Show 20 Linesstatic inline int raiseExcept(int excepts) {
// Manual, Vol 1". // Manual, Vol 1".
// FPU status word is read for each exception seperately as the // FPU status word is read for each exception seperately as the
// exception handler can potentially write to it (typically to clear // exception handler can potentially write to it (typically to clear
// the corresponding exception flag). By reading it separately, we // the corresponding exception flag). By reading it separately, we
// ensure that the writes by the exception handler are maintained // ensure that the writes by the exception handler are maintained
// when raising the next exception. // when raising the next exception.
if (statusValue & internal::ExceptionFlags::Invalid) { auto raiseHelper = [](uint16_t singleExceptFlag) {
internal::X87StateDescriptor state; internal::X87StateDescriptor state;
internal::getX87StateDescriptor(state); internal::getX87StateDescriptor(state);
state.StatusWord |= internal::ExceptionFlags::Invalid; state.StatusWord |= singleExceptFlag;
internal::writeX87StateDescriptor(state);
internal::fwait();
}
if (statusValue & internal::ExceptionFlags::DivByZero) {
internal::X87StateDescriptor state;
internal::getX87StateDescriptor(state);
state.StatusWord |= internal::ExceptionFlags::DivByZero;
internal::writeX87StateDescriptor(state);
internal::fwait();
}
if (statusValue & internal::ExceptionFlags::Overflow) {
internal::X87StateDescriptor state;
internal::getX87StateDescriptor(state);
state.StatusWord |= internal::ExceptionFlags::Overflow;
internal::writeX87StateDescriptor(state);
internal::fwait();
}
if (statusValue & internal::ExceptionFlags::Underflow) {
internal::X87StateDescriptor state;
internal::getX87StateDescriptor(state);
state.StatusWord |= internal::ExceptionFlags::Underflow;
internal::writeX87StateDescriptor(state);
internal::fwait();
}
if (statusValue & internal::ExceptionFlags::Inexact) {
internal::X87StateDescriptor state;
internal::getX87StateDescriptor(state);
state.StatusWord |= internal::ExceptionFlags::Inexact;
internal::writeX87StateDescriptor(state); internal::writeX87StateDescriptor(state);
internal::fwait(); internal::fwait();
};
if (statusValue & internal::ExceptionFlags::Invalid)
raiseHelper(internal::ExceptionFlags::Invalid);
if (statusValue & internal::ExceptionFlags::DivByZero)
raiseHelper(internal::ExceptionFlags::DivByZero);
if (statusValue & internal::ExceptionFlags::Overflow)
raiseHelper(internal::ExceptionFlags::Overflow);
if (statusValue & internal::ExceptionFlags::Underflow)
raiseHelper(internal::ExceptionFlags::Underflow);
if (statusValue & internal::ExceptionFlags::Inexact)
raiseHelper(internal::ExceptionFlags::Inexact);
#ifdef __FE_DENORM
if (statusValue & internal::ExceptionFlags::Denormal) {
raiseHelper(internal::ExceptionFlags::Denormal);
} }
#endif // __FE_DENORM
// There is no special synchronization scheme available to // There is no special synchronization scheme available to
// raise SEE exceptions. So, we will ignore that for now. // raise SEE exceptions. So, we will ignore that for now.
// Just plain writing to the MXCSR register does not guarantee // Just plain writing to the MXCSR register does not guarantee
// the exception handler will be called. // the exception handler will be called.
return 0; return 0;
} }
▲ Show 20 Lines • Show All 77 Lines • Show Last 20 Lines