This is an alternate fix (see D87835) for a bug where a NaN constant
gets wrongly transformed into Infinity via truncation.
In this patch, we uniformly convert any SNaN to QNaN while raising
'invalid op'.
But we don't have a way to directly specify a 32-bit SNaN value in LLVM IR,
so those are always encoded/decoded by calling convert from/to 64-bit hex.
See D88664 for a clang fix needed to allow this change.
Differential Revision: https://reviews.llvm.org/D88238
For example, the assert in isSignificandAllZeros allowed NumHighBits
to be integerPartWidth. But since it is used directly as a shift amount
it must be less than integerPartWidth.
Patch IEEEFloat::isSignificandAllZeros and IEEEFloat::isSignificandAllOnes to behave correctly in the case that the size of the significand is a multiple of the width of the integerParts making up the significand.
The patch to IEEEFloat::isSignificandAllOnes fixes bug 34579, and the patch to IEEE:Float:isSignificandAllZeros fixes the unit test "APFloatTest.x87Next" I added here. I have included both in this diff since the changes are very similar.
Patch by Andrew Briand
We shift the significand right on a truncation, but that needs to be made NaN-safe:
always set at least 1 bit in the significand.
https://llvm.org/PR43907
See D88238 for the likely follow-up (but needs some plumbing fixes before it can proceed).
Differential Revision: https://reviews.llvm.org/D87835
Some constructors of IEEEFloat do not initialize member variable exponent.
Fix it by initializing exponent with the following values:
For NaNs, the `exponent` is `maxExponent+1`.
For Infinities, the `exponent` is `maxExponent+1`.
For Zeroes, the `exponent` is `maxExponent-1`.
Patch by: @nullptr.cpp (Yang Fan)
Differential Revision: https://reviews.llvm.org/D86997
Bfloat type has an 8-bit exponent so the exponent of NaN/Inf numbers
must be 0xff instead of 0x1f. This is probably a copy-paste mistake
from the half float type.
Reviewed By: lattner
Differential Revision: https://reviews.llvm.org/D81302
Summary:
The BFloat IR type is introduced to provide support for, initially, the BFloat16
datatype introduced with the Armv8.6 architecture (optional from Armv8.2
onwards). It has an 8-bit exponent and a 7-bit mantissa and behaves like an IEEE
754 floating point IR type.
This is part of a patch series upstreaming Armv8.6 features. Subsequent patches
will upstream intrinsics support and C-lang support for BFloat.
Reviewers: SjoerdMeijer, rjmccall, rsmith, liutianle, RKSimon, craig.topper, jfb, LukeGeeson, sdesmalen, deadalnix, ctetreau
Subscribers: hiraditya, llvm-commits, danielkiss, arphaman, kristof.beyls, dexonsmith
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D78190
Now compiler defines 5 sets of constants to represent rounding mode.
These are:
1. `llvm::APFloatBase::roundingMode`. It specifies all 5 rounding modes
defined by IEEE-754 and is used in `APFloat` implementation.
2. `clang::LangOptions::FPRoundingModeKind`. It specifies 4 of 5 IEEE-754
rounding modes and a special value for dynamic rounding mode. It is used
in clang frontend.
3. `llvm::fp::RoundingMode`. Defines the same values as
`clang::LangOptions::FPRoundingModeKind` but in different order. It is
used to specify rounding mode in in IR and functions that operate IR.
4. Rounding mode representation used by `FLT_ROUNDS` (C11, 5.2.4.2.2p7).
Besides constants for rounding mode it also uses a special value to
indicate error. It is convenient to use in intrinsic functions, as it
represents platform-independent representation for rounding mode. In this
role it is used in some pending patches.
5. Values like `FE_DOWNWARD` and other, which specify rounding mode in
library calls `fesetround` and `fegetround`. Often they represent bits
of some control register, so they are target-dependent. The same names
(not values) and a special name `FE_DYNAMIC` are used in
`#pragma STDC FENV_ROUND`.
The first 4 sets of constants are target independent and could have the
same numerical representation. It would simplify conversion between the
representations. Also now `clang::LangOptions::FPRoundingModeKind` and
`llvm::fp::RoundingMode` do not contain the value for IEEE-754 rounding
direction `roundTiesToAway`, although it is supported natively on
some targets.
This change defines all the rounding mode type via one `llvm::RoundingMode`,
which also contains rounding mode for IEEE rounding direction `roundTiesToAway`.
Differential Revision: https://reviews.llvm.org/D77379
Behavior of IEEEFloat::roundToIntegral is aligned with IEEE-754
operation roundToIntegralExact. In partucular this function now:
- returns opInvalid for signaling NaNs,
- returns opInexact if the result of rounding differs from argument.
Differential Revision: https://reviews.llvm.org/D75246
Add support for converting Signaling NaN, and a NaN Payload from string.
The NaNs (the string "nan" or "NaN") may be prefixed with 's' or 'S' for defining a Signaling NaN.
A payload for a NaN can be specified as a suffix.
It may be a octal/decimal/hexadecimal number in parentheses or without.
Differential Revision: https://reviews.llvm.org/D69773
`APFLoat::convertFromString` returns `Expected` result, which must be
"checked" if the LLVM_ENABLE_ABI_BREAKING_CHECKS preprocessor flag is
set.
To mark an `Expected` result as "checked" we must consume the `Error`
within.
In many cases, we are only interested in knowing if an error occured,
without the need to examine the error info. This is achieved, easily,
with the `errorToBool()` API.
Up until now, the arguments to `fusedMultiplyAdd` are passed by
reference. We must save the `Addend` value on the beginning of the
function, before we modify `this`, as they may be the same reference.
To fix this, we now pass the `addend` parameter of `multiplySignificand`
by value (instead of by-ref), and have a default value of zero.
Fix PR44051.
Differential Revision: https://reviews.llvm.org/D70422
Fix incorrect determination of the bigger number out of the two
subtracted, while subnormal numbers are involved.
Fixes PR44010.
Differential Revision: https://reviews.llvm.org/D69772
Summary:
When using ConstantExpr we often need the result of the expression to be kept in the AST. Currently this is done on a by the node that needs the result and has been done multiple times for enumerator, for constexpr variables... . This patch adds to ConstantExpr the ability to store the result of evaluating the expression. no functional changes expected.
Changes:
- Add trailling object to ConstantExpr that can hold an APValue or an uint64_t. the uint64_t is here because most ConstantExpr yield integral values so there is an optimized layout for integral values.
- Add basic* serialization support for the trailing result.
- Move conversion functions from an enum to a fltSemantics from clang::FloatingLiteral to llvm::APFloatBase. this change is to make it usable for serializing APValues.
- Add basic* Import support for the trailing result.
- ConstantExpr created in CheckConvertedConstantExpression now stores the result in the ConstantExpr Node.
- Adapt AST dump to print the result when present.
basic* : None, Indeterminate, Int, Float, FixedPoint, ComplexInt, ComplexFloat,
the result is not yet used anywhere but for -ast-dump.
Reviewers: rsmith, martong, shafik
Reviewed By: rsmith
Subscribers: rnkovacs, hiraditya, dexonsmith, cfe-commits, llvm-commits
Tags: #clang, #llvm
Differential Revision: https://reviews.llvm.org/D62399
llvm-svn: 363493
This was mentioned both in https://www.viva64.com/en/b/0629/ and by scan-build checks
........
There's concerns this may just introduce a use-after-free instead.....
llvm-svn: 360770
This patch has three related fixes to improve float literal lexing:
1. Make AsmLexer::LexDigit handle floats without a decimal point more
consistently.
2. Make AsmLexer::LexFloatLiteral print an error for floats which are
apparently missing an "e".
3. Make APFloat::convertFromString use binutils-compatible exponent
parsing.
Together, this fixes some cases where a float would be incorrectly
rejected, fixes some cases where the compiler would crash, and improves
diagnostics in some cases.
Patch by Brandon Jones.
Differential Revision: https://reviews.llvm.org/D57321
llvm-svn: 357214
to reflect the new license.
We understand that people may be surprised that we're moving the header
entirely to discuss the new license. We checked this carefully with the
Foundation's lawyer and we believe this is the correct approach.
Essentially, all code in the project is now made available by the LLVM
project under our new license, so you will see that the license headers
include that license only. Some of our contributors have contributed
code under our old license, and accordingly, we have retained a copy of
our old license notice in the top-level files in each project and
repository.
llvm-svn: 351636
losesInfo would be left unset when no conversion needs to be done. A
caller such as InstCombine's fitsInFPType would then branch on an
uninitialized value.
Caught using valgrind on an out-of-tree target.
Differential Revision: https://reviews.llvm.org/D46645
llvm-svn: 332087
Summary:
Unnormal values are a feature of some very old x87 processors. We handle
them correctly for the most part -- the only exception was an unnormal
value whose significand happened to be zero. In this case the APFloat
was still initialized as normal number (category = fcNormal), but a
subsequent toString operation would assert because the math would
produce nonsensical values for the zero significand.
During review, it was decided that the correct way to fix this is to
treat all unnormal values as NaNs (as that is what any >=386 processor
will do).
The issue was discovered because LLDB would crash when trying to print
some "long double" values.
Reviewers: skatkov, scanon, gottesmm
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D41868
llvm-svn: 331884
See r331124 for how I made a list of files missing the include.
I then ran this Python script:
for f in open('filelist.txt'):
f = f.strip()
fl = open(f).readlines()
found = False
for i in xrange(len(fl)):
p = '#include "llvm/'
if not fl[i].startswith(p):
continue
if fl[i][len(p):] > 'Config':
fl.insert(i, '#include "llvm/Config/llvm-config.h"\n')
found = True
break
if not found:
print 'not found', f
else:
open(f, 'w').write(''.join(fl))
and then looked through everything with `svn diff | diffstat -l | xargs -n 1000 gvim -p`
and tried to fix include ordering and whatnot.
No intended behavior change.
llvm-svn: 331184
The method IEEEFloat::convertFromStringSpecials() does not recognize
the "+Inf" and "-Inf" strings but these strings are printed for
the double Infinities by the IEEEFloat::toString().
This patch adds the "+Inf" and "-Inf" strings to the list of recognized
patterns in IEEEFloat::convertFromStringSpecials().
Re-landing after fix.
Reviewers: sberg, bogner, majnemer, timshen, rnk, skatkov, gottesmm, bkramer, scanon, anna
Reviewed By: anna
Subscribers: mkazantsev, FlameTop, llvm-commits, reames, apilipenko
Differential Revision: https://reviews.llvm.org/D38030
llvm-svn: 321054
fmod specification requires the sign of the remainder is
the same as numerator in case remainder is zero.
Reviewers: gottesmm, scanon, arsenm, davide, craig.topper
Reviewed By: scanon
Subscribers: wdng, llvm-commits
Differential Revision: https://reviews.llvm.org/D39225
llvm-svn: 317081
The method IEEEFloat::convertFromStringSpecials() does not recognize
the "+Inf" and "-Inf" strings but these strings are printed for
the double Infinities by the IEEEFloat::toString().
This patch adds the "+Inf" and "-Inf" strings to the list of recognized
patterns in IEEEFloat::convertFromStringSpecials().
Reviewers: sberg, bogner, majnemer, timshen, rnk, skatkov, gottesmm, bkramer, scanon
Reviewed By: skatkov
Subscribers: apilipenko, reames, llvm-commits
Differential Revision: https://reviews.llvm.org/D38030
llvm-svn: 316156
Summary:
Add LLVM_FORCE_ENABLE_DUMP cmake option, and use it along with
LLVM_ENABLE_ASSERTIONS to set LLVM_ENABLE_DUMP.
Remove NDEBUG and only use LLVM_ENABLE_DUMP to enable dump methods.
Move definition of LLVM_ENABLE_DUMP from config.h to llvm-config.h so
it'll be picked up by public headers.
Differential Revision: https://reviews.llvm.org/D38406
llvm-svn: 315590
This should fix the bug https://bugs.llvm.org/show_bug.cgi?id=12906
To print the FP constant AsmWriter does the following:
1) convert FP value to String (actually using snprintf function which is locale dependent).
2) Convert String back to FP Value
3) Compare original and got FP values. If they are not equal just dump as hex.
The problem happens on the 2nd step when APFloat does not expect group delimiter or
fraction delimiter other than period symbol and so on, which can be produced on the
first step if LLVM library is used in an environment with corresponding locale set.
To fix this issue the locale independent APFloat:toString function is used.
However it prints FP values slightly differently than snprintf does. Specifically
it suppress trailing zeros in significant, use capital E and so on.
It results in 117 test failures during make check.
To avoid this I've also updated APFloat.toString a bit to pass make check at least.
Reviewers: sberg, bogner, majnemer, sanjoy, timshen, rnk
Reviewed By: timshen, rnk
Subscribers: rnk, llvm-commits
Differential Revision: https://reviews.llvm.org/D32276
llvm-svn: 300943
This patch uses lshrInPlace to replace code where the object that lshr is called on is being overwritten with the result.
This adds an lshrInPlace(const APInt &) version as well.
Differential Revision: https://reviews.llvm.org/D32155
llvm-svn: 300566
This patch is one step to attempt to unify the main APInt interface and the tc functions used by APFloat.
This patch adds a WordType to APInt and uses that in all the tc functions. I've added temporary typedefs to APFloat to alias it to integerPart to keep the patch size down. I'll work on removing that in a future patch.
In future patches I hope to reuse the tc functions to implement some of the main APInt functionality.
I may remove APINT_ from BITS_PER_WORD and WORD_SIZE constants so that we don't have the repetitive APInt::APINT_ externally.
Differential Revision: https://reviews.llvm.org/D31523
llvm-svn: 299341
We had various variants of defining dump() functions in LLVM. Normalize
them (this should just consistently implement the things discussed in
http://lists.llvm.org/pipermail/cfe-dev/2014-January/034323.html
For reference:
- Public headers should just declare the dump() method but not use
LLVM_DUMP_METHOD or #if !defined(NDEBUG) || defined(LLVM_ENABLE_DUMP)
- The definition of a dump method should look like this:
#if !defined(NDEBUG) || defined(LLVM_ENABLE_DUMP)
LLVM_DUMP_METHOD void MyClass::dump() {
// print stuff to dbgs()...
}
#endif
llvm-svn: 293359
Simon Pilgrim