32 Commits

Author SHA1 Message Date
Jin Huang
e67f934c12
[profcheck] Fix profle metatdata propagation for Large Integer operations (#175862)
This PR improves the propagation of profile metadata within the
ExpandIRInsts pass. When lowering large integer division operations, the
pass now ensures that branch weights are correctly attached to the
generated control flow, preventing the loss of profile data during IR
expansion.

This PR improves signed and unsigned division/remainder for non-native
bit widths (e.g., `sdiv/udiv i129`, `srem/urem i129`) and implemented
Heuristic-Based Branch Weights labeling using established heuristics for
edge cases e.g., `Division-by-zero guards` and `Magnitude comparisons
between dividends and divisors`.

It also adds detailed comments within the expansion logic to explain the
rationale behind specific branch weight choices and the underlying
mathematical invariants.

Please refer to the implementation details in the source code for the
specific branch weight values and the logic governing their application.

Co-authored-by: Jonas Devlieghere <jonas@devlieghere.com>
2026-01-23 10:29:20 -08:00
Rahul Joshi
fa789dffb1
[NFC] Rename Intrinsic::getDeclaration to getOrInsertDeclaration (#111752)
Rename the function to reflect its correct behavior and to be consistent
with `Module::getOrInsertFunction`. This is also in preparation of
adding a new `Intrinsic::getDeclaration` that will have behavior similar
to `Module::getFunction` (i.e, just lookup, no creation).
2024-10-11 05:26:03 -07:00
Rahul Joshi
5a40bc2383
[NFC] Fix typo in function name generatedUnsignedRemainderCode (#110743)
Rename `generatedUnsignedRemainderCode` to
`generateUnsignedRemainderCode`.
2024-10-02 06:05:41 -07:00
Stephen Tozer
d75f9dd1d2 Revert "[IR][NFC] Update IRBuilder to use InsertPosition (#96497)"
Reverts the above commit, as it updates a common header function and
did not update all callsites:

  https://lab.llvm.org/buildbot/#/builders/29/builds/382

This reverts commit 6481dc57612671ebe77fe9c34214fba94e1b3b27.
2024-06-24 18:00:22 +01:00
Stephen Tozer
6481dc5761
[IR][NFC] Update IRBuilder to use InsertPosition (#96497)
Uses the new InsertPosition class (added in #94226) to simplify some of
the IRBuilder interface, and removes the need to pass a BasicBlock
alongside a BasicBlock::iterator, using the fact that we can now get the
parent basic block from the iterator even if it points to the sentinel.
This patch removes the BasicBlock argument from each constructor or call
to setInsertPoint.

This has no functional effect, but later on as we look to remove the
`Instruction *InsertBefore` argument from instruction-creation
(discussed
[here](https://discourse.llvm.org/t/psa-instruction-constructors-changing-to-iterator-only-insertion/77845)),
this will simplify the process by allowing us to deprecate the
InsertPosition constructor directly and catch all the cases where we use
instructions rather than iterators.
2024-06-24 17:27:43 +01:00
Craig Topper
ace05124f5 [IntegerDivision][AMDGPU] Use CreateLogicalOr to block poison propagation.
There are two ctlz intrinsics here with the zero_is_poison flag
set. There are also two comparisons that check if either of the
inputs the ctlzs are zero. We need to use a logical or to block
the poison from the ctlz if either of the inputs is zero.

Reviewed By: arsenm, aqjune

Differential Revision: https://reviews.llvm.org/D130680
2022-09-15 09:38:02 -07:00
Nuno Lopes
858fe8664e Expand Div/Rem: consider the case where the dividend is zero
So we can't use ctlz in poison-producing mode
2022-09-01 17:04:26 +01:00
Nuno Lopes
fa154a9170 Revert "Expand Div/Rem: consider the case where the dividend is zero"
This reverts commit 4aed09868b5a51a29aade11d9d412c3313310f29.
2022-09-01 12:11:22 +01:00
Nuno Lopes
4aed09868b Expand Div/Rem: consider the case where the dividend is zero
So we can't use ctlz in poison-producing mode
2022-09-01 12:00:03 +01:00
Matthias Gehre
3e39b27101 [llvm/CodeGen] Add ExpandLargeDivRem pass
Adds a pass ExpandLargeDivRem to expand div/rem instructions
with more than 128 bits into a loop computing that value.

As discussed on https://reviews.llvm.org/D120327, this approach has the advantage
that it is independent of the runtime library. This also helps the clang driver,
which otherwise would need to understand enough about the runtime library
to know whether to allow _BitInts with more than 128 bits.

Targets are still free to disable this pass and instead provide a faster
implementation in a runtime library.

Fixes https://github.com/llvm/llvm-project/issues/44994

Differential Revision: https://reviews.llvm.org/D126644
2022-08-26 11:55:15 +01:00
serge-sans-paille
a494ae43be Cleanup includes: TransformsUtils
Estimation on the impact on preprocessor output:
before: 1065307662
after:  1064800684

Discourse thread: https://discourse.llvm.org/t/include-what-you-use-include-cleanup
Differential Revision: https://reviews.llvm.org/D120741
2022-03-01 21:00:07 +01:00
Chandler Carruth
2946cd7010 Update the file headers across all of the LLVM projects in the monorepo
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
2019-01-19 08:50:56 +00:00
Fangrui Song
f78650a8de Remove trailing space
sed -Ei 's/[[:space:]]+$//' include/**/*.{def,h,td} lib/**/*.{cpp,h}

llvm-svn: 338293
2018-07-30 19:41:25 +00:00
Adrian Prantl
4dfcc4a788 Remove @brief commands from doxygen comments, too.
This is a follow-up to r331272.

We've been running doxygen with the autobrief option for a couple of
years now. This makes the \brief markers into our comments
redundant. Since they are a visual distraction and we don't want to
encourage more \brief markers in new code either, this patch removes
them all.

Patch produced by
  for i in $(git grep -l '\@brief'); do perl -pi -e 's/\@brief //g' $i & done

https://reviews.llvm.org/D46290

llvm-svn: 331275
2018-05-01 16:10:38 +00:00
Duncan P. N. Exon Smith
ec6f7fed54 TransformUtils: Avoid getNodePtrUnchecked() in integer division, NFC
Stop relying on `getNodePtrUnchecked()` being useful on invalid
iterators.  This function is documented to be for internal use only, and
the pointer type will eventually have to change to remove UB from
ilist_iterator.  Instead, check the iterator before it has been
invalidated.

llvm-svn: 261497
2016-02-21 20:14:29 +00:00
Craig Topper
582d8ecf6a [Transforms] Use asserts instead of ifs around llvm_unreachable. NFC
llvm-svn: 256405
2015-12-25 02:04:17 +00:00
Duncan P. N. Exon Smith
5b4c837c58 TransformUtils: Remove implicit ilist iterator conversions, NFC
Continuing the work from last week to remove implicit ilist iterator
conversions.  First related commit was probably r249767, with some more
motivation in r249925.  This edition gets LLVMTransformUtils compiling
without the implicit conversions.

No functional change intended.

llvm-svn: 250142
2015-10-13 02:39:05 +00:00
David Blaikie
ff6409d096 Simplify IRBuilder::CreateCall* by using ArrayRef+initializer_list/braced init only
llvm-svn: 237624
2015-05-18 22:13:54 +00:00
Michael Ilseman
a7202bdbed Fix heap-use-after-free bug in expandSDiv when the operands are
constants, as discovered by ASAN.

Patch by Mehdi Amini!

llvm-svn: 221401
2014-11-05 21:28:24 +00:00
Chandler Carruth
964daaaf19 [Modules] Fix potential ODR violations by sinking the DEBUG_TYPE
definition below all of the header #include lines, lib/Transforms/...
edition.

This one is tricky for two reasons. We again have a couple of passes
that define something else before the includes as well. I've sunk their
name macros with the DEBUG_TYPE.

Also, InstCombine contains headers that need DEBUG_TYPE, so now those
headers #define and #undef DEBUG_TYPE around their code, leaving them
well formed modular headers. Fixing these headers was a large motivation
for all of these changes, as "leaky" macros of this form are hard on the
modules implementation.

llvm-svn: 206844
2014-04-22 02:55:47 +00:00
Michael Ilseman
d930c19d20 Add support for software expansion of 64-bit integer division instructions.
Patch by Dmitri Shtilman!

llvm-svn: 195116
2013-11-19 06:54:19 +00:00
Pedro Artigas
e40467b589 Enhance integer division emulation support to handle types smaller than 32 bits,
enhancement done the trivial way; by extending inputs and truncating outputs 
which is addequate for targets with little or no support for integer arithmetic
on integer types less than 32 bits.

llvm-svn: 176139
2013-02-26 23:33:20 +00:00
Chandler Carruth
9fb823bbd4 Move all of the header files which are involved in modelling the LLVM IR
into their new header subdirectory: include/llvm/IR. This matches the
directory structure of lib, and begins to correct a long standing point
of file layout clutter in LLVM.

There are still more header files to move here, but I wanted to handle
them in separate commits to make tracking what files make sense at each
layer easier.

The only really questionable files here are the target intrinsic
tablegen files. But that's a battle I'd rather not fight today.

I've updated both CMake and Makefile build systems (I think, and my
tests think, but I may have missed something).

I've also re-sorted the includes throughout the project. I'll be
committing updates to Clang, DragonEgg, and Polly momentarily.

llvm-svn: 171366
2013-01-02 11:36:10 +00:00
Chandler Carruth
ed0881b2a6 Use the new script to sort the includes of every file under lib.
Sooooo many of these had incorrect or strange main module includes.
I have manually inspected all of these, and fixed the main module
include to be the nearest plausible thing I could find. If you own or
care about any of these source files, I encourage you to take some time
and check that these edits were sensible. I can't have broken anything
(I strictly added headers, and reordered them, never removed), but they
may not be the headers you'd really like to identify as containing the
API being implemented.

Many forward declarations and missing includes were added to a header
files to allow them to parse cleanly when included first. The main
module rule does in fact have its merits. =]

llvm-svn: 169131
2012-12-03 16:50:05 +00:00
Michael Ilseman
a398d4cfaf Expansions for u/srem, using the udiv expansion. More unit tests for udiv and u/srem.
Fixed issue with Release build.

llvm-svn: 164654
2012-09-26 01:55:01 +00:00
Chad Rosier
88387f5332 Revert r164614 to appease the buildbots.
llvm-svn: 164627
2012-09-25 19:57:20 +00:00
Michael Ilseman
506150a071 Expansions for u/srem, using the udiv expansion. More unit tests for udiv and u/srem.
llvm-svn: 164614
2012-09-25 17:56:47 +00:00
Michael Ilseman
5117db54ff Renaming functions to match coding style guidelines
llvm-svn: 164238
2012-09-19 18:14:45 +00:00
Michael Ilseman
370a1a1c94 Doxygen-ify comments
llvm-svn: 164235
2012-09-19 16:25:57 +00:00
Michael Ilseman
1db690d15e Put the * and & next to the variable, rather than the type.
llvm-svn: 164232
2012-09-19 16:17:20 +00:00
Benjamin Kramer
47196e6cd5 IntegerDivision: Style cleanups, avoid warning about mixing || and && without parens.
llvm-svn: 164216
2012-09-19 13:03:07 +00:00
Michael Ilseman
52059da858 New utility for expanding integer division for targets that don't support it.
Implementation derived from compiler-rt's implementation of signed and unsigned integer division.

llvm-svn: 164173
2012-09-18 22:02:40 +00:00