This commit adjusts the order of two swappable if statements to
make code cleaner.
Reviewed By: lattner, nikic
Differential Revision: https://reviews.llvm.org/D99648
I'm not sure if it would be legal by the IR reference to introduce
an addrspacecast here, since the IR reference is a bit vague on
the exact semantics, but at least for our usage of it (and I
suspect for many other's usage) it is not. For us, addrspacecasts
between non-integral address spaces carry frontend information that the
optimizer cannot deduce afterwards in a generic way (though we
have frontend specific passes in our pipline that do propagate
these). In any case, I'm sure nobody is using it this way at
the moment, since it would have introduced inttoptrs, which
are definitely illegal.
Fixes PR38375
Co-authored-by: Keno Fischer <keno@alumni.harvard.edu>
Reviewed By: reames
Differential Revision: https://reviews.llvm.org/D50010
If we try to coerce a vector of non-integral pointers to a narrower type (either narrower vector or single pointer), we use inttoptr and violate the semantics of non-integral pointers. In theory, we can handle many of these cases, we just need to use a different code idiom to convert without going through inttoptr and back.
This shows up as wrong code bugs, and in some cases, crashes due to failed asserts. Modeled after a change which has lived downstream for a couple years, though completely rewritten to be more idiomatic.
Here we teach the ConstantFolding analysis pass that it is not legal to
replace a load of a bitcast constant (having a non-integral addrspace)
with a bitcast of the value of that constant (with a different
non-integral addrspace).
But also teach it that certain bit patterns are always known and
convertable (a fact it already uses elsewhere). This required us to also
fix a globalopt test, since, after this change, LLVM is able to realize
that the test actually is a valid transform (NULL is always a known
bit-pattern) and so it doesn't need to emit the failure remarks for it.
Also simplify some of the negative tests for transforms by avoiding a
type change in their bitcast, and add positive versions of the same
tests, to show that they otherwise should work.
Differential Revision: https://reviews.llvm.org/D59730
This could previously make it more complicated for ConstantFolding
later, leading to a higher likelyhood it would have to reject the
expression, even though zero seems like probably the common case here.
Differential Revision: https://reviews.llvm.org/D59730
Spin-off from D75407. As described there, ConstantFoldConstant()
currently returns null for non-ConstantExpr/ConstantVector inputs,
but otherwise always returns non-null, independently of whether
any folding has happened or not.
This is confusing and makes consumer code more complicated.
I would expect either that ConstantFoldConstant() returns only if
it actually folded something, or that it always returns non-null.
I'm going to the latter possibility here, which appears to be more
useful considering existing usage.
Differential Revision: https://reviews.llvm.org/D75543
Static method MemoryDependenceResults::getLoadLoadClobberFullWidthSize
does not have or use any info specific to MemoryDependenceResults.
Move it to its only user: VNCoercion.
Summary: Move some code around, in preparation for later fixes
to the non-integral addrspace handling (D59661)
Patch By Jameson Nash <jameson@juliacomputing.com>
Reviewed By: reames, loladiro
Differential Revision: https://reviews.llvm.org/D59729
llvm-svn: 362853
Noticed these while doing a final sweep of the code to make sure I hadn't missed anything in my last couple of patches. The (minor) missed optimization was noticed because of the stylistic fix to avoid an overly specific cast.
llvm-svn: 354412
Same case as for memset and memcpy, but this time for clobbering stores and loads. We still can't allow coercion to or from non-integrals, regardless of the transform.
Now that I'm done the whole little sequence, it seems apparent that we'd entirely missed reasoning about clobbers in the original GVN support for non-integral pointers.
My appologies, I thought we'd upstreamed all of this, but it turns out we were still carrying a downstream hack which hid all of these issues. My chanks to Cherry Zhang for helping debug.
llvm-svn: 354407
Problem is very similiar to the one fixed for memsets in r354399, we try to coerce a value to non-integral type, and then crash while try to do so. Since we shouldn't be doing such coercions to start with, easy fix. From inspection, I see two other cases which look to be similiar and will follow up with most test cases and fixes if confirmed.
llvm-svn: 354403
GVN generally doesn't forward structs or array types, but it *will* forward vector types to non-vectors and vice versa. As demonstrated in tests, we need to inhibit the same set of transforms for vector of non-integral pointers as for non-integral pointers themselves.
llvm-svn: 354401
If we encountered a location where we tried to forward the value of a memset to a load of a non-integral pointer, we crashed. Such a forward is not legal in general, but we can forward null pointers. Test for both cases are included.
llvm-svn: 354399
This cleans up all LoadInst creation in LLVM to explicitly pass the
value type rather than deriving it from the pointer's element-type.
Differential Revision: https://reviews.llvm.org/D57172
llvm-svn: 352911
Summary:
A reprise of D25849.
This crash was found through fuzzing some time ago and was documented in PR28879.
No check for load size has been added due to the following tests:
- Transforms/GVN/invariant.group.ll
- Transforms/GVN/pr10820.ll
These tests expect load sizes that are not a multiple of eight.
Thanks to @davide for the original patch.
Reviewers: nlopes, davide, RKSimon, reames, efriedma
Reviewed By: efriedma
Subscribers: davide, llvm-commits, Prazek
Differential Revision: https://reviews.llvm.org/D48330
llvm-svn: 335294
The DEBUG() macro is very generic so it might clash with other projects.
The renaming was done as follows:
- git grep -l 'DEBUG' | xargs sed -i 's/\bDEBUG\s\?(/LLVM_DEBUG(/g'
- git diff -U0 master | ../clang/tools/clang-format/clang-format-diff.py -i -p1 -style LLVM
- Manual change to APInt
- Manually chage DOCS as regex doesn't match it.
In the transition period the DEBUG() macro is still present and aliased
to the LLVM_DEBUG() one.
Differential Revision: https://reviews.llvm.org/D43624
llvm-svn: 332240
Summary:
This fixes the immediate crash caused by introducing an incorrect inttoptr
before attempting the conversion. There may still be a legality
check missing somewhere earlier for non-integral pointers, but this change
seems necessary in any case.
Reviewers: sanjoy, dberlin
Reviewed By: dberlin
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D32623
llvm-svn: 302587
Summary:
See http://llvm.org/docs/LangRef.html#non-integral-pointer-type
The NewGVN test does not fail without these changes (perhaps it does
try to coerce pointers <-> integers to begin with?), but I added the
test case anyway.
Reviewers: dberlin
Subscribers: mcrosier, llvm-commits, Prazek
Differential Revision: https://reviews.llvm.org/D32208
llvm-svn: 300730
NFCI.
Summary:
This is ground work for the changes to enable coercion in NewGVN.
GVN doesn't care if they end up constant because it eliminates as it goes.
NewGVN cares.
IRBuilder and ConstantFolder deliberately present the same interface,
so we use this to our advantage to templatize our functions to make
them either constant only or not.
Reviewers: davide
Subscribers: llvm-commits, Prazek
Differential Revision: https://reviews.llvm.org/D30928
llvm-svn: 298262
Summary:
These are the functions used to determine when values of loads can be
extracted from stores, etc, and to perform the necessary insertions to
do this. There are no changes to the functions themselves except
reformatting, and one case where memdep was informed of a removed load
(which was pushed into the caller).
Reviewers: davide
Subscribers: mgorny, llvm-commits, Prazek
Differential Revision: https://reviews.llvm.org/D30478
llvm-svn: 297438
qixingxue