This version contains a fix to add values for which the state in ParamState change
to the worklist if the state in ValueState did not change. To avoid adding the
same value multiple times, mergeInValue returns true, if it added the value to
the worklist. The value is added to the worklist depending on its state in
ValueState.
Original message:
For comparisons with parameters, we can use the ParamState lattice
elements which also provide constant range information. This improves
the code for PR33253 further and gets us closer to use
ValueLatticeElement for all values.
Also, as we are using the range information in the solver directly, we
do not need tryToReplaceWithConstantRange afterwards anymore.
Reviewers: dberlin, mssimpso, davide, efriedma
Reviewed By: mssimpso
Differential Revision: https://reviews.llvm.org/D43762
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@336098 91177308-0d34-0410-b5e6-96231b3b80d8
changeToUnreachable may remove PHI nodes from executable blocks we found values
for and we would fail to replace them. By changing dead blocks to unreachable after
we replaced constants in all executable blocks, we ensure such PHI nodes are replaced
by their known value before.
Fixes PR37780.
Reviewers: efriedma, davide
Reviewed By: efriedma
Differential Revision: https://reviews.llvm.org/D48421
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@335588 91177308-0d34-0410-b5e6-96231b3b80d8
r335150 should resolve the issues with the clang-with-thin-lto-ubuntu
and clang-with-lto-ubuntu builders.
Original message:
This patch updates IPSCCP to use PredicateInfo to propagate
facts to true branches predicated by EQ and to false branches
predicated by NE.
As a follow up, we should be able to extend it to also propagate additional
facts about nonnull.
Reviewers: davide, mssimpso, dberlin, efriedma
Reviewed By: davide, dberlin
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@335206 91177308-0d34-0410-b5e6-96231b3b80d8
Review feedback from r328165. Split out just the one function from the
file that's used by Analysis. (As chandlerc pointed out, the original
change only moved the header and not the implementation anyway - which
was fine for the one function that was used (since it's a
template/inlined in the header) but not in general)
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@333954 91177308-0d34-0410-b5e6-96231b3b80d8
This patch updates IPSCCP to use PredicateInfo to propagate
facts to true branches predicated by EQ and to false branches
predicated by NE.
As a follow up, we should be able to extend it to also propagate additional
facts about nonnull.
Reviewers: davide, mssimpso, dberlin, efriedma
Reviewed By: davide, dberlin
Differential Revision: https://reviews.llvm.org/D45330
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@333740 91177308-0d34-0410-b5e6-96231b3b80d8
Reverting this to see if this is causing the failures of the
clang-with-thin-lto-ubuntu bot.
[IPSCCP] Use PredicateInfo to propagate facts from cmp instructions.
This patch updates IPSCCP to use PredicateInfo to propagate
facts to true branches predicated by EQ and to false branches
predicated by NE.
As a follow up, we should be able to extend it to also propagate additional
facts about nonnull.
Reviewers: davide, mssimpso, dberlin, efriedma
Reviewed By: davide, dberlin
Differential Revision: https://reviews.llvm.org/D45330
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@333323 91177308-0d34-0410-b5e6-96231b3b80d8
This patch updates IPSCCP to use PredicateInfo to propagate
facts to true branches predicated by EQ and to false branches
predicated by NE.
As a follow up, we should be able to extend it to also propagate additional
facts about nonnull.
Reviewers: davide, mssimpso, dberlin, efriedma
Reviewed By: davide, dberlin
Differential Revision: https://reviews.llvm.org/D45330
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@333268 91177308-0d34-0410-b5e6-96231b3b80d8
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
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@332240 91177308-0d34-0410-b5e6-96231b3b80d8
For comparisons with parameters, we can use the ParamState lattice
elements which also provide constant range information. This improves
the code for PR33253 further and gets us closer to use
ValueLatticeElement for all values.
Also, as we are using the range information in the solver directly, we
do not need tryToReplaceWithConstantRange afterwards anymore.
Reviewers: dberlin, mssimpso, davide, efriedma
Reviewed By: mssimpso
Differential Revision: https://reviews.llvm.org/D43762
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@328307 91177308-0d34-0410-b5e6-96231b3b80d8
Transforms/Scalar/SCCP.cpp implemented both the Scalar and IPO SCCP, but
this meant Transforms/Scalar including Transfroms/IPO headers, creating
a circular dependency. (IPO depends on Scalar already) - so move the IPO
SCCP shims out into IPO and the basic library implementation accessible
from Scalar/SCCP.h to be used from the IPO/SCCP.cpp implementation.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@328250 91177308-0d34-0410-b5e6-96231b3b80d8
Remove #include of Transforms/Scalar.h from Transform/Utils to fix layering.
Transforms depends on Transforms/Utils, not the other way around. So
remove the header and the "createStripGCRelocatesPass" function
declaration (& definition) that is unused and motivated this dependency.
Move Transforms/Utils/Local.h into Analysis because it's used by
Analysis/MemoryBuiltins.cpp.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@328165 91177308-0d34-0410-b5e6-96231b3b80d8
getCompare returns true, false or undef constants if the comparison can
be evaluated, or nullptr if it cannot. This is in line with what
ConstantExpr::getCompare returns. It also allows us to use
ConstantExpr::getCompare for comparing constants.
Reviewers: davide, mssimpso, dberlin, anna
Reviewed By: davide
Differential Revision: https://reviews.llvm.org/D43761
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@326720 91177308-0d34-0410-b5e6-96231b3b80d8
Do not replace results of `musttail` calls with a constant if the
call itself can't be removed.
Do not zap returns of `musttail` callees, if the call site can't be
removed and replaced with a constant.
Do not zap returns of `musttail`-calling blocks, this breaks
invariant too.
Patch by Fedor Indutny
Differential Revision: https://reviews.llvm.org/D43695
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@326404 91177308-0d34-0410-b5e6-96231b3b80d8
Summary:
When performing constant propagation for call instructions we have historically replaced all uses of the return from a call, but not removed the call itself. This is required for correctness if the calls have side effects, however the compiler should be able to safely remove calls that don't have side effects.
This allows the compiler to completely fold away calls to functions that have no side effects if the inputs are constant and the output can be determined at compile time.
Reviewers: davide, sanjoy, bruno, dberlin
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D38856
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@322125 91177308-0d34-0410-b5e6-96231b3b80d8
I thought this was responsible for PR35723, but I was
wrong, the issue lies elsewhere. Revert while I debug.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@321975 91177308-0d34-0410-b5e6-96231b3b80d8
This code was originally removed and replace with an assertion
because believed unnecessary. It turns out there was simply
no test coverage for this case, and the constant folder doesn't
yet know about patterns like `br undef %label1, %label2`.
Presumably at some point the constant folder might learn about
these patterns, but it's a broader change.
A testcase will be added to make sure this doesn't regress again
in the future.
Fixes PR35723.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@321402 91177308-0d34-0410-b5e6-96231b3b80d8
After the dataflow algorithm proves that an argument is constant,
it replaces it value with the integer constant and drops the lattice
value associated to the DEF.
e.g. in the example we have @f() that's called twice:
call @f(undef, ...)
call @f(2, ...)
`undef` MEET 2 = 2 so we replace the argument and all its uses with
the constant 2.
Shortly after, tryToReplaceWithConstantRange() tries to get the lattice
value for the argument we just replaced, causing an assertion.
This function is a little peculiar as it runs when we're doing replacement
and not as part of the solver but still queries the solver.
The fix is that of checking whether we replaced the value already and
get a temporary lattice value for the constant.
Thanks to Zhendong Su for the report!
Fixes PR35357.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@318817 91177308-0d34-0410-b5e6-96231b3b80d8
This version of the patch includes a fix addressing a stage2 LTO buildbot
failure and addressed some additional nits.
Original commit message:
This updates the SCCP solver to use of the ValueElement lattice for
parameters, which provides integer range information. The range
information is used to remove unneeded icmp instructions.
For the following function, f() can be optimized to ret i32 2 with
this change
source_filename = "sccp.c"
target datalayout = "e-m:e-i64:64-f80:128-n8:16:32:64-S128"
target triple = "x86_64-unknown-linux-gnu"
; Function Attrs: norecurse nounwind readnone uwtable
define i32 @main() local_unnamed_addr #0 {
entry:
%call = tail call fastcc i32 @f(i32 1)
%call1 = tail call fastcc i32 @f(i32 47)
%add3 = add nsw i32 %call, %call1
ret i32 %add3
}
; Function Attrs: noinline norecurse nounwind readnone uwtable
define internal fastcc i32 @f(i32 %x) unnamed_addr #1 {
entry:
%c1 = icmp sle i32 %x, 100
%cmp = icmp sgt i32 %x, 300
%. = select i1 %cmp, i32 1, i32 2
ret i32 %.
}
attributes #1 = { noinline }
Reviewers: davide, sanjoy, efriedma, dberlin
Reviewed By: davide, dberlin
Subscribers: mcrosier, gberry, mssimpso, dberlin, llvm-commits
Differential Revision: https://reviews.llvm.org/D36656
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@316891 91177308-0d34-0410-b5e6-96231b3b80d8
This version of the patch includes a fix addressing a stage2 LTO buildbot
failure and addressed some additional nits.
Original commit message:
This updates the SCCP solver to use of the ValueElement lattice for
parameters, which provides integer range information. The range
information is used to remove unneeded icmp instructions.
For the following function, f() can be optimized to ret i32 2 with
this change
source_filename = "sccp.c"
target datalayout = "e-m:e-i64:64-f80:128-n8:16:32:64-S128"
target triple = "x86_64-unknown-linux-gnu"
; Function Attrs: norecurse nounwind readnone uwtable
define i32 @main() local_unnamed_addr #0 {
entry:
%call = tail call fastcc i32 @f(i32 1)
%call1 = tail call fastcc i32 @f(i32 47)
%add3 = add nsw i32 %call, %call1
ret i32 %add3
}
; Function Attrs: noinline norecurse nounwind readnone uwtable
define internal fastcc i32 @f(i32 %x) unnamed_addr #1 {
entry:
%c1 = icmp sle i32 %x, 100
%cmp = icmp sgt i32 %x, 300
%. = select i1 %cmp, i32 1, i32 2
ret i32 %.
}
attributes #1 = { noinline }
Reviewers: davide, sanjoy, efriedma, dberlin
Reviewed By: davide, dberlin
Subscribers: mcrosier, gberry, mssimpso, dberlin, llvm-commits
Differential Revision: https://reviews.llvm.org/D36656
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@316887 91177308-0d34-0410-b5e6-96231b3b80d8
This patch moves some common utility functions out of IPSCCP and makes them
available globally. The functions determine if interprocedural data-flow
analyses can propagate information through function returns, arguments, and
global variables.
Differential Revision: https://reviews.llvm.org/D37638
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@315719 91177308-0d34-0410-b5e6-96231b3b80d8
We are not allowed to reason about an initializer value without first
consulting hasDefinitiveInitializer.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@309594 91177308-0d34-0410-b5e6-96231b3b80d8
Going through the Constant methods requires redetermining that the Constant is a ConstantInt and then calling isZero/isOne/isMinusOne.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@307292 91177308-0d34-0410-b5e6-96231b3b80d8
Instead of using the SCCP homegrown one. We should eventually
make the private SCCP version disappear, but that wont' be today.
PR33143 tracks this issue.
Add braces for consistency while here. No functional change intended.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@303706 91177308-0d34-0410-b5e6-96231b3b80d8
and to expose a handle to represent the actual case rather than having
the iterator return a reference to itself.
All of this allows the iterator to be used with common STL facilities,
standard algorithms, etc.
Doing this exposed some missing facilities in the iterator facade that
I've fixed and required some work to the actual iterator to fully
support the necessary API.
Differential Revision: https://reviews.llvm.org/D31548
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@300032 91177308-0d34-0410-b5e6-96231b3b80d8
Summary:
Resolve indirect branch target when possible.
This potentially eliminates more basicblocks and result in better evaluation for phi and other things.
Reviewers: davide, efriedma, sanjoy
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D30322
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@299830 91177308-0d34-0410-b5e6-96231b3b80d8
Summary:
BranchInst, SwitchInst (with non-default case) with Undef as input is not
possible at this point. As we always default-fold terminator to one target in
ResolvedUndefsIn and set the input accordingly.
So we should only have constantint/blockaddress here.
If ConstantFoldTerminator fails, that could mean 2 things.
1. ConstantFoldTerminator is doing something unexpected, i.e. not folding on constantint
or blockaddress and not making blocks that should be dead dead.
2. This is not a terminator on constantint or blockaddress. Its on a constant or
overdefined, then this block should not be dead.
In both cases, we should assert.
Reviewers: davide, efriedma, sanjoy
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D30381
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@296281 91177308-0d34-0410-b5e6-96231b3b80d8
It's not clear the change I made a good idea, and it definitely needs
further discussion. Thanks to Eli for pointing out.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@293846 91177308-0d34-0410-b5e6-96231b3b80d8
This tries to address what Hal defined (in the post-commit review of
r293727) a long-standing problem with noinline, where we end up
de facto inlining trivial functions e.g.
__attribute__((noinline)) int patatino(void) { return 5; }
because of return value propagation.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@293799 91177308-0d34-0410-b5e6-96231b3b80d8
This can prove that:
extern int f;
int g() {
int x = 0;
for (int i = 0; i < 365; ++i) {
x /= f;
}
return x;
}
always returns zero. Thanks to Sanjoy for confirming this
transformation actually made sense (bugs are mine).
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@292531 91177308-0d34-0410-b5e6-96231b3b80d8
Florian Hahn