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Differential D132155

[flang] Fold SPACING() correctly when result is subnormal
ClosedPublic

Authored by klausler on Aug 18 2022, 11:16 AM.

Details

Reviewers
PeteSteinfeld
Commits
rG92afe8021352: [flang] Fold SPACING() correctly when result is subnormal
Summary

The intrinsic function SPACING() was being folded to the smallest
normal number (TINY(x)) rather than to a smaller subnormal result
when that result really was subnormal.

Diff Detail

Event Timeline

klausler created this revision.Aug 18 2022, 11:16 AM
Herald added a project: Restricted Project. · View Herald TranscriptAug 18 2022, 11:16 AM
Herald added a subscriber: jdoerfert. · View Herald Transcript
klausler requested review of this revision.Aug 18 2022, 11:16 AM
Harbormaster completed remote builds in B182045: Diff 453719.Aug 18 2022, 12:16 PM
PeteSteinfeld accepted this revision.Aug 18 2022, 1:49 PM

All builds and tests correctly and looks good.

This revision is now accepted and ready to land.Aug 18 2022, 1:49 PM
Closed by commit rG92afe8021352: [flang] Fold SPACING() correctly when result is subnormal (authored by klausler). · Explain WhyAug 18 2022, 2:24 PM
This revision was automatically updated to reflect the committed changes.
klausler added a commit: rG92afe8021352: [flang] Fold SPACING() correctly when result is subnormal.

Revision Contents

PathSize
flang/
lib/
Evaluate/
3 lines
test/
Evaluate/
2 lines

Diff 453786

flang/lib/Evaluate/real.cpp

Show First 20 Lines • Show All 743 Lines • ▼ Show 20 Linestemplate <typename W, int P> Real<W, P> Real<W, P>::SPACING() const {
if (IsNotANumber()) { if (IsNotANumber()) {
return *this; return *this;
} else if (IsInfinite()) { } else if (IsInfinite()) {
return NotANumber(); return NotANumber();
} else if (IsZero()) { } else if (IsZero()) {
return TINY(); return TINY();
} else { } else {
Real result; Real result;
result.Normalize( result.Normalize(false, Exponent(), Fraction::MASKR(1));
false, Exponent() - binaryPrecision + 1, Fraction::MASKL(1));
return result; return result;
} }
} }
// 16.9.171 // 16.9.171
template <typename W, int P> template <typename W, int P>
Real<W, P> Real<W, P>::SET_EXPONENT(int expo) const { Real<W, P> Real<W, P>::SET_EXPONENT(int expo) const {
if (IsNotANumber()) { if (IsNotANumber()) {
Show All 22 Lines

flang/test/Evaluate/fold-spacing.f90

! RUN: %python %S/test_folding.py %s %flang_fc1 ! RUN: %python %S/test_folding.py %s %flang_fc1
! Tests folding of SPACING() and RRSPACING ! Tests folding of SPACING() and RRSPACING
module m module m
logical, parameter :: test_1 = spacing(3.0) == scale(1.0, -22) logical, parameter :: test_1 = spacing(3.0) == scale(1.0, -22)
logical, parameter :: test_2 = spacing(-3.0) == scale(1.0, -22) logical, parameter :: test_2 = spacing(-3.0) == scale(1.0, -22)
logical, parameter :: test_3 = spacing(3.0d0) == scale(1.0, -51) logical, parameter :: test_3 = spacing(3.0d0) == scale(1.0, -51)
logical, parameter :: test_4 = spacing(0.) == tiny(0.) logical, parameter :: test_4 = spacing(0.) == tiny(0.)
logical, parameter :: test_5 = spacing(tiny(0.)) == 1.e-45
logical, parameter :: test_6 = spacing(8388608.) == 1.
logical, parameter :: test_11 = rrspacing(3.0) == scale(0.75, 24) logical, parameter :: test_11 = rrspacing(3.0) == scale(0.75, 24)
logical, parameter :: test_12 = rrspacing(-3.0) == scale(0.75, 24) logical, parameter :: test_12 = rrspacing(-3.0) == scale(0.75, 24)
logical, parameter :: test_13 = rrspacing(3.0d0) == scale(0.75, 53) logical, parameter :: test_13 = rrspacing(3.0d0) == scale(0.75, 53)
logical, parameter :: test_14 = rrspacing(0.) == 0. logical, parameter :: test_14 = rrspacing(0.) == 0.
end module end module