Summary:
Existing heuristic uses the ratio between the function entry
frequency and the loop invocation frequency to find cold loops. However,
even if the loop executes frequently, if it has a small trip count per
each invocation, vectorization is not beneficial. On the other hand,
even if the loop invocation frequency is much smaller than the function
invocation frequency, if the trip count is high it is still beneficial
to vectorize the loop.
This patch uses estimated trip count computed from the profile metadata
as a primary metric to determine coldness of the loop. If the estimated
trip count cannot be computed, it falls back to the original heuristics.
Reviewers: Ayal, mssimpso, mkuper, danielcdh, wmi, tejohnson
Reviewed By: tejohnson
Subscribers: tejohnson, mzolotukhin, llvm-commits
Differential Revision: https://reviews.llvm.org/D32451
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@305729 91177308-0d34-0410-b5e6-96231b3b80d8
Summary:
Some optimizations in AddReachableCodeToWorklist did not update
the MadeIRChange state. This could happen both when removing
trivially dead instructions (DCE) and at constant folds.
It is essential that changes to the IR is reported correctly,
since for example InstCombinePass::run() will indicate that all
analyses are preserved otherwise.
And the CGPassManager determines if the CallGraph is up-to-date
based on status from InstructionCombiningPass::runOnFunction().
The new test case early_dce_clobbers_callgraph.ll is a reproducer
for some asserts that started to trigger after changes in the
inliner in r305245. With this patch the test case passes again.
Reviewers: sanjoy, craig.topper, dblaikie
Reviewed By: craig.topper
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D34346
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@305725 91177308-0d34-0410-b5e6-96231b3b80d8
This seems to be interacting badly with ASan somehow, causing false reports of
heap-buffer overflows: PR33514.
> Summary:
> The patch makes instruction count the highest priority for
> LSR solution for X86 (previously registers had highest priority).
>
> Reviewers: qcolombet
>
> Differential Revision: http://reviews.llvm.org/D30562
>
> From: Evgeny Stupachenko <evstupac@gmail.com>
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@305720 91177308-0d34-0410-b5e6-96231b3b80d8
Summary:
These 4 patterns have the same one use check repeated twice for each. Once without a cast and one with. But the cast has no effect on what method is called.
For the OR case I believe it is always profitable regardless of the number of uses since we'll never increase the instruction count.
For the AND case I believe it is profitable if the pair of xors has one use such that we'll get rid of it completely. Or if the C value is something freely invertible, in which case the not doesn't cost anything.
Reviewers: spatel, majnemer
Reviewed By: spatel
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D34308
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@305705 91177308-0d34-0410-b5e6-96231b3b80d8
Summary:
Currently we don't try to do anything with vector xors.
This patch adds support for removing duplicate pairs from a chain of vector xors as its pretty easy to support. We still dont' try to combine the xors with and/ors, but I might try that in a future patch.
Reviewers: mcrosier, davide, resistor
Reviewed By: mcrosier
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D34338
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@305704 91177308-0d34-0410-b5e6-96231b3b80d8
Summary:
After a single predecessor is merged into a basic block, we need to invalidate
the LVI information for the new merged block, when LVI is not provably true for
all of instructions in the new block.
The test cases added show the correct LVI information using the LVI printer
pass.
Reviewers: reames, dberlin, davide, sanjoy
Reviewed by: dberlin, davide
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D34108
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@305699 91177308-0d34-0410-b5e6-96231b3b80d8
Summary: use AA to tell whether a load can be moved before a call that writes to memory.
Reviewers: dberlin, davide, sanjoy, hfinkel
Reviewed By: hfinkel
Subscribers: hfinkel, llvm-commits
Differential Revision: https://reviews.llvm.org/D34115
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@305698 91177308-0d34-0410-b5e6-96231b3b80d8
Summary:
This allows strlen to be moved out of the loop in case its argument is
not modified in the loop in LICM.
Reviewers: hfinkel, davide, sanjoy, dberlin
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D34323
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@305641 91177308-0d34-0410-b5e6-96231b3b80d8
Summary:
When we fold vector constants that are operands of phi's that feed into select,
we need to set the correct insertion point for the *new* selects that get generated.
The correct insertion point is the incoming block for the phi.
Such cases can occur with patch r298845, which fixed folding of
vector constants, but the new selects could be inserted incorrectly (as the added
test case shows).
Reviewers: majnemer, spatel, sanjoy
Reviewed by: spatel
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D34162
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@305591 91177308-0d34-0410-b5e6-96231b3b80d8
The recommit fixes two bugs: The first one is to use CurrentBlock instead of
PREInstr's Parent as param of performScalarPREInsertion because the Parent
of a clone instruction may be uninitialized. The second one is stop PRE when
CurrentBlock to its predecessor is a backedge and an operand of CurInst is
defined inside of CurrentBlock. The same value defined inside of loop in last
iteration can not be regarded as available.
Right now scalarpre doesn't have phi-translate support, so it will miss some
simple pre opportunities. Like the following testcase, current scalarpre cannot
recognize the last "a * b" is fully redundent because a and b used by the last
"a * b" expr are both defined by phis.
long a[100], b[100], g1, g2, g3;
__attribute__((pure)) long goo();
void foo(long a, long b, long c, long d) {
g1 = a * b;
if (__builtin_expect(g2 > 3, 0)) {
a = c;
b = d;
g2 = a * b;
}
g3 = a * b; // fully redundant.
}
The patch adds phi-translate support in scalarpre. This is only a temporary
solution before the newpre based on newgvn is available.
Differential Revision: https://reviews.llvm.org/D32252
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@305578 91177308-0d34-0410-b5e6-96231b3b80d8
Summary:
Background: http://lists.llvm.org/pipermail/llvm-dev/2017-May/112779.html
This change is to alter the prototype for the atomic memcpy intrinsic. The prototype itself is being changed to more closely resemble the semantics and parameters of the llvm.memcpy intrinsic -- to ease later combination of the llvm.memcpy and atomic memcpy intrinsics. Furthermore, the name of the atomic memcpy intrinsic is being changed to make it clear that it is not a generic atomic memcpy, but specifically a memcpy is unordered atomic.
Reviewers: reames, sanjoy, efriedma
Reviewed By: reames
Subscribers: mzolotukhin, anna, llvm-commits, skatkov
Differential Revision: https://reviews.llvm.org/D33240
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@305558 91177308-0d34-0410-b5e6-96231b3b80d8
This is a NFC code refactoring and interface cleanup. This paves the
way to enable outlining-only mode for the partial inliner.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@305530 91177308-0d34-0410-b5e6-96231b3b80d8
This is a fix for PR33292 that shows a case of extremely long compilation
of a single .c file with clang, with most time spent within SCEV.
We have a mechanism of limiting recursion depth for getAddExpr to avoid
long analysis in SCEV. However, there are calls from getAddExpr to getMulExpr
and back that do not propagate the info about depth. As result of this, a chain
getAddExpr -> ... .> getAddExpr -> getMulExpr -> getAddExpr -> ... -> getAddExpr
can be extremely long, with every segment of getAddExpr's being up to max depth long.
This leads either to long compilation or crash by stack overflow. We face this situation while
analyzing big SCEVs in the test of PR33292.
This patch applies the same limit on max expression depth for getAddExpr and getMulExpr.
Differential Revision: https://reviews.llvm.org/D33984
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This way we end up not looking at PHI args already removed.
MemSSA now goes through the updater so we can prune
it to avoid having redundant MemoryPHI arguments, but that
doesn't quite work for the general case.
Discussed with Daniel Berlin, fixes PR33406.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@305409 91177308-0d34-0410-b5e6-96231b3b80d8
Doing so breaks compilation of the following C program
(under -fprofile-instr-generate):
__attribute__((always_inline)) inline int foo() { return 0; }
int main() { return foo(); }
At link time, we fail because taking the address of an
available_externally function creates an undefined external reference,
which the TU cannot provide.
Emitting the function definition into the object file at all appears to
be a violation of the langref: "Globals with 'available_externally'
linkage are never emitted into the object file corresponding to the LLVM
module."
Differential Revision: https://reviews.llvm.org/D34134
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@305327 91177308-0d34-0410-b5e6-96231b3b80d8
Summary:
Leave an updated VP metadata on the fallback memcpy intrinsic after
specialization. This can be used for later possible expansion based on
the average of the remaining values.
Reviewers: davidxl
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D34164
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@305321 91177308-0d34-0410-b5e6-96231b3b80d8
Summary: Fixes an issue using RegisterStandardPasses from a statically linked object before PassManagerBuilder::addGlobalExtension is called from a dynamic library.
Reviewers: efriedma, theraven
Reviewed By: efriedma
Subscribers: mehdi_amini, mgorny, llvm-commits
Differential Revision: https://reviews.llvm.org/D33515
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@305303 91177308-0d34-0410-b5e6-96231b3b80d8
This restores the order of evaluation (& conditionalized evaluation) of
isTriviallyDeadInstruction, InlineHistoryIncludes, and shouldInline
(with the addition of a shouldInline call after
isTriviallyDeadInstruction) from before r305245.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@305267 91177308-0d34-0410-b5e6-96231b3b80d8
Summary:
After RS4GC, we should drop metadata that is no longer valid. These metadata
is used by optimizations scheduled after RS4GC, and can cause a miscompile.
One such metadata is invariant.load which is used by LICM sinking transform.
After rewriting statepoints, the address of a load maybe relocated. With
invariant.load metadata on a load instruction, LICM sinking assumes the
loaded value (from a dererenceable address) to be invariant, and
rematerializes the load operand and the load at the exit block.
This transforms the IR to have an unrelocated use of the
address after a statepoint, which is incorrect.
Other metadata we conservatively remove are related to
dereferenceability and noalias metadata.
This patch drops such metadata on store and load instructions after
rewriting statepoints.
Reviewers: reames, sanjoy, apilipenko
Reviewed by: reames
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D33756
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@305234 91177308-0d34-0410-b5e6-96231b3b80d8
Summary:
Use MemorySSA for memory dependency checking in the EarlyCSE pass at the
start of the function simplification portion of the pipeline. We rely
on the fact that GVNHoist runs just after this pass of EarlyCSE to
amortize the MemorySSA construction cost since GVNHoist uses MemorySSA
and EarlyCSE preserves it.
This is turned off by default. A follow-up change will turn it on to
allow for easier reversion in case it breaks something.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@305146 91177308-0d34-0410-b5e6-96231b3b80d8
