In LLVM_ENABLE_STATS=0 builds, `llvm::Statistic` maps to `llvm::NoopStatistic`
but has 3 unused pointers. GlobalOpt considers that the pointers can potentially
retain allocated objects, so GlobalOpt cannot optimize out the `NoopStatistic`
variables (see D69428 for more context), wasting 23KiB for stage 2 clang.
This patch makes `NoopStatistic` empty and thus reclaims the wasted space. The
clang size is even smaller than applying D69428 (slightly smaller in both .bss and
.text).
```
# This means the D69428 optimization on clang is mostly nullified by this patch.
HEAD+D69428: size(.bss) = 0x0725a8
HEAD+D101211: size(.bss) = 0x072238
# bloaty - HEAD+D69428 vs HEAD+D101211
# With D101211, we also save a lot of string table space (.rodata).
FILE SIZE VM SIZE
-------------- --------------
-0.0% -32 -0.0% -24 .eh_frame
-0.0% -336 [ = ] 0 .symtab
-0.0% -360 [ = ] 0 .strtab
[ = ] 0 -0.2% -880 .bss
-0.0% -2.11Ki -0.0% -2.11Ki .rodata
-0.0% -2.89Ki -0.0% -2.89Ki .text
-0.0% -5.71Ki -0.0% -5.88Ki TOTAL
```
Note: LoopFuse is a disabled pass. This patch adds `#if LLVM_ENABLE_STATS` so
`OptimizationRemarkMissed` is skipped in LLVM_ENABLE_STATS==0 builds. If these
`OptimizationRemarkMissed` are useful and not noisy, we can replace
`llvm::Statistic` with `llvm::TrackingStatistic` in the future.
Reviewed By: lattner
Differential Revision: https://reviews.llvm.org/D101211
When transforming a loop terminating condition into a "max" comparison,
the DebugLoc from the old condition should be set on the newly created
comparison. They are the same operation, just optimized. Fixes PR48067.
Differential Revision: https://reviews.llvm.org/D98218
This patch updates performSymbolicPredicateInfoEvaluation to manage
registering additional dependencies using ExprResult. Similar to D99987,
this fixes an issues where we failed to track the correct dependency for
a phi-of-ops value, which is marked as temporary.
Fixes PR49873.
Reviewed By: asbirlea, ruiling
Differential Revision: https://reviews.llvm.org/D100560
performSymbolicEvaluation is used to obtain the symbolic expression when
visiting instructions and this is used to determine their congruence
class.
performSymbolicEvaluation only creates expressions for certain
instructions (via createExpression). For unsupported instructions,
'unknown' expression are created.
The use of createExpression in processOutgoingEdges means we may
simplify the condition in processOutgoingEdges to a constant in the
initial round of processing, but we use Unknown(I) for the congruence
class. If an operand of I changes the expression Unknown(I) stays the
same, so there is no update of the congruence class of I. Hence it
won't get re-visited. So if an operand of I changes in a way that causes
createExpression to return different result, this update is missed.
This patch updates the code to use performSymbolicEvaluation, to be
symmetric with the congruence class updating code.
Reviewed By: asbirlea
Differential Revision: https://reviews.llvm.org/D99990
This recommits 4f5da356ff, including
explicit implementations of move a constructor and deleted copy
constructors/assignment operators, to fix failures with some compilers.
This reverts the revert 74854d00e8.
If we are using a simplified value, we need to add an extra
dependency this value , because changes to the class of the
simplified value may require us to invalidate any decision based on
that value.
This is done by adding such values as additional users, however the
current code does not excludes temporary instructions.
At the moment, this means that we miss those dependencies for
phi-of-ops, because they are temporary instructions at this point. We
instead need to add the extra dependencies to the root instruction of
the phi-of-ops.
This patch pushes the responsibility of adding extra users to the
callers of createExpression & performSymbolicEvaluation. At those
points, it is clearer which real instruction to pick.
Alternatively we could either pass the 'real' instruction as additional
argument or use another map, but I think the approach in the patch makes
things a bit easier to follow.
Fixes PR35074.
Reviewed By: asbirlea
Differential Revision: https://reviews.llvm.org/D99987
Fixes PR47627
This fix suppresses rerolling a loop which has an unrerollable
instruction.
Sample IR for the explanation below:
```
define void @foo([2 x i32]* nocapture %a) {
entry:
br label %loop
loop:
; base instruction
%indvar = phi i64 [ 0, %entry ], [ %indvar.next, %loop ]
; unrerollable instructions
%stptrx = getelementptr inbounds [2 x i32], [2 x i32]* %a, i64 %indvar, i64 0
store i32 999, i32* %stptrx, align 4
; extra simple arithmetic operations, used by root instructions
%plus20 = add nuw nsw i64 %indvar, 20
%plus10 = add nuw nsw i64 %indvar, 10
; root instruction 0
%ldptr0 = getelementptr inbounds [2 x i32], [2 x i32]* %a, i64 %plus20, i64 0
%value0 = load i32, i32* %ldptr0, align 4
%stptr0 = getelementptr inbounds [2 x i32], [2 x i32]* %a, i64 %plus10, i64 0
store i32 %value0, i32* %stptr0, align 4
; root instruction 1
%ldptr1 = getelementptr inbounds [2 x i32], [2 x i32]* %a, i64 %plus20, i64 1
%value1 = load i32, i32* %ldptr1, align 4
%stptr1 = getelementptr inbounds [2 x i32], [2 x i32]* %a, i64 %plus10, i64 1
store i32 %value1, i32* %stptr1, align 4
; loop-increment and latch
%indvar.next = add nuw nsw i64 %indvar, 1
%exitcond = icmp eq i64 %indvar.next, 5
br i1 %exitcond, label %exit, label %loop
exit:
ret void
}
```
In the loop rerolling pass, `%indvar` and `%indvar.next` are appended
to the `LoopIncs` vector in the `LoopReroll::DAGRootTracker::findRoots`
function.
Before this fix, two instructions with `unrerollable instructions`
comment above are marked as `IL_All` at the end of the
`LoopReroll::DAGRootTracker::collectUsedInstructions` function,
as well as instructions with `extra simple arithmetic operations`
comment and `loop-increment and latch` comment. It is incorrect
because `IL_All` means that the instruction should be executed in all
iterations of the rerolled loop but the `store` instruction should
not.
This fix rejects instructions which may have side effects and don't
belong to def-use chains of any root instructions and reductions.
See https://bugs.llvm.org/show_bug.cgi?id=47627 for more information.
This patch allows PRE of the following type of loads:
```
preheader:
br label %loop
loop:
br i1 ..., label %merge, label %clobber
clobber:
call foo() // Clobbers %p
br label %merge
merge:
...
br i1 ..., label %loop, label %exit
```
Into
```
preheader:
%x0 = load %p
br label %loop
loop:
%x.pre = phi(x0, x2)
br i1 ..., label %merge, label %clobber
clobber:
call foo() // Clobbers %p
%x1 = load %p
br label %merge
merge:
x2 = phi(x.pre, x1)
...
br i1 ..., label %loop, label %exit
```
So instead of loading from %p on every iteration, we load only when the actual clobber happens.
The typical pattern which it is trying to address is: hot loop, with all code inlined and
provably having no side effects, and some side-effecting calls on cold path.
The worst overhead from it is, if we always take clobber block, we make 1 more load
overall (in preheader). It only matters if loop has very few iteration. If clobber block is not taken
at least once, the transform is neutral or profitable.
There are several improvements prospect open up:
- We can sometimes be smarter in loop-exiting blocks via split of critical edges;
- If we have block frequency info, we can handle multiple clobbers. The only obstacle now is that
we don't know if their sum is colder than the header.
Differential Revision: https://reviews.llvm.org/D99926
Reviewed By: reames
This makes the memcpy-memcpy and memcpy-memset optimizations work for
variable sizes as long as they are equal, relaxing the old restriction
that they are constant integers. If they're not equal, the old
requirement that they are constant integers with certain size
restrictions is used.
The implementation works by pushing the length tests further down in the
code, which reveals some places where it's enough that the lengths are
equal (but not necessarily constant).
Differential Revision: https://reviews.llvm.org/D100870
This change fixes a latent bug which was exposed by a change currently in review (https://reviews.llvm.org/D99802#2685032).
The story on this is a bit involved. Without this change, what ended up happening with the pending review was that we'd strip attributes off intrinsics, and then selectiondag would fail to lower the intrinsic. Why? Because the lowering of the intrinsic relies on the presence of the readonly attribute. We don't have a matcher to select the case where there's a glue node needed.
Now, on the surface, this still seems like a codegen bug. However, here it gets fun. I was unable to reproduce this with a standalone test at all, and was pretty much struck until skatkov provided the critical detail. This reproduces only when RS4GC and codegen are run in the same process and context. Why? Because it turns out we can't roundtrip the stripped attribute through serialized IR!
We'll happily print out the missing attribute, but when we parse it back, the auto-upgrade logic has a side effect of blindly overwriting attributes on intrinsics with those specified in Intrinsics.td. This makes it impossible to exercise SelectionDAG from a standalone test case.
At this point, I decided to treat this an RS4GC bug as a) we don't need to strip in this case, and b) I could write a test which shows the correct behavior to ensure this doesn't break again in the future.
As an aside, I'd originally set out to handle libfuncs too - since in theory they might have the same issues - but backed away quickly when I realized how the semantics of builtin, nobuiltin, and no-builtin-x all interacted. I'm utterly convinced that no part of the optimizer handles that correctly, and decided not to open that can of worms here.
During store promotion, we check whether the pointer was captured
to exclude potential reads from other threads. However, we're only
interested in captures before or inside the loop. Check this using
PointerMayBeCapturedBefore against the loop header.
Differential Revision: https://reviews.llvm.org/D100706
Recently processMinMaxIntrinsic has been added and we started to observe a number of analysis get invalidated after CVP. The problem is CVP conservatively returns 'true' even if there were no modifications to IR. I found one more place besides processMinMaxIntrinsic which has the same problem. I think processMinMaxIntrinsic and similar should better have boolean return status to prevent similar issue reappear in future.
Reviewed By: lebedev.ri
Differential Revision: https://reviews.llvm.org/D100538
Such attributes can either be unset, or set to "true" or "false" (as string).
throughout the codebase, this led to inelegant checks ranging from
if (Fn->getFnAttribute("no-jump-tables").getValueAsString() == "true")
to
if (Fn->hasAttribute("no-jump-tables") && Fn->getFnAttribute("no-jump-tables").getValueAsString() == "true")
Introduce a getValueAsBool that normalize the check, with the following
behavior:
no attributes or attribute set to "false" => return false
attribute set to "true" => return true
Differential Revision: https://reviews.llvm.org/D99299
These were misleading, they're more of a "clear" than an "invalidate".
We shouldn't be individually clearing analysis results. Either we clear
all analyses when some IR becomes invalid, or we properly go through
invalidation.
There was only one use of this, which can be simulated with
AM.invalidate(F, PA).
Reviewed By: mtrofin
Differential Revision: https://reviews.llvm.org/D100519
This patch changed the isLegalUse check to ensure that
LSRInstance::GenerateConstantOffsetsImpl generates an
offset that results in a legal addressing mode and
formula. The check is changed to look similar to the
assert check used for illegal formulas.
Differential Revision: https://reviews.llvm.org/D100383
Change-Id: Iffb9e32d59df96b8f072c00f6c339108159a009a
If the PHI-of-ops simplifies to an existing value, no real PHI is
created, which means the dependencies between the
PHI-of-ops and its operands is not materialized in IR. At the
moment, we fail to create a real PHI node for the PHI-of-ops,
because the PHI-of-ops root instruction is not re-visited if
one of the PHI-of-ops operands changes. We need to add the
operands as additional users in this case.
Even with this patch, there are still some dependencies
missing. I will continue tackling the outstanding
reporeted crashes in this area.
Fixes PR36501, PR42422, PR42557.
Reviewed By: asbirlea
Differential Revision: https://reviews.llvm.org/D66924
This refactors SCCP and creates a SCCPSolver interface and class so that it can
be used by other passes and transformations. We will use this in D93838, which
adds a function specialisation pass.
This is based on an early version by Vinay Madhusudan.
Differential Revision: https://reviews.llvm.org/D93762
Jump threading can replace select then unconditional branch with
conditional branch, but when doing so loses debug info.
This destructive transform is eventually leading to a failed Verifier
run during full LTO builds of the Linux kernel with CFI and KCOV
enabled, as reported in PR39531.
ModuleSanitizerCoveragePass will insert calls to
__sanitizer_cov_trace_pc, and sometimes split critical edges,
using whatever debug info may or may not exist for the branch for
the added libcall. Since we can inline calls to
__sanitizer_cov_trace_pc due to LTO, this can lead to the error
observed in PR39531 when the debug info isn't propagated to
the libcall, because of prior destructive transforms that failed to
retain debug info.
Reviewed By: dblaikie
Differential Revision: https://reviews.llvm.org/D100137
Say we have
%1=min(%a,%b)
%2=min(%b,%c)
%3=min(%2,%a)
The optimization will try to reassociate the later one so that we can rewrite it to %3=min(%1, %c) and remove %2.
But if %2 has another uses outside of %3 then we can't remove %2 and end up with:
%1=min(%a,%b)
%2=min(%b,%c)
%3=min(%1, %c)
This doesn't harm by itself except it is not profitable and changes IR for no good reason.
What is bad it triggers next iteration which finds out that optimization is applicable to %2 and %3 and generates:
%1=min(%a,%b)
%2=min(%b,%c)
%3=min(%1,%c)
%4=min(%2,%a)
and so on...
The solution is to prevent optimization in the first place if intermediate result (%2) has side uses and
known to be not removed.
Reviewed By: mkazantsev
Differential Revision: https://reviews.llvm.org/D100170
The default is likely wrong.
Out of all the callees, only a single one needs to pass-in false (JumpThread),
everything else either already passes true, or should pass true.
Until the default is flipped, at least make it harder to unintentionally
add new callees with UseBlockValue=false.
Add an ability to store `Offset` between partially aliased location. Use this
storage within returned `ResultAlias` instead of caching it in `AAQueryInfo`.
Reviewed By: asbirlea
Differential Revision: https://reviews.llvm.org/D98718
Main reason is preparation to transform AliasResult to class that contains
offset for PartialAlias case.
Reviewed By: asbirlea
Differential Revision: https://reviews.llvm.org/D98027
Previously loading the vtable used in calling a virtual method in a loop
was not hoisted out of the loop. This fixes that.
canSinkOrHoistInst() itself doesn't check that the load operands are
loop invariant, callers also check that separately.
Reviewed By: rnk
Differential Revision: https://reviews.llvm.org/D99784
meetBDVState looks pretty difficult to read and follow.
This is purely NFC but doing several things:
1) Combine meet and meetBDVState
2) Move the function to be a member of BDVState
3) Make BDVState be a mutable object
4) Convert switch to sequence of ifs
5) Adds comments.
Reviewers: reames, dantrushin
Reviewed By: reames
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D99064
This fixes a "Cached first special instruction is wrong!" assert.
The assert fires because replacing a value with another can cause an
instruction to no longer be "special" to ICF. In this case,
devirtualization happened, turning an indirect call to a
call to a willreturn function which is no longer special.
Reviewed By: nikic, rnk
Differential Revision: https://reviews.llvm.org/D99977
After D99249 we use three different loop pass managers for LICM,
LoopRotate and LICM+LoopUnswitch. This happens because LazyBFI
and LazyBPI are not preserved by LoopRotate (note that D74640
is no longer needed). Avoid this by marking them as preserved.
My understanding of D86156 is that it is okay to simply preserve
them (which LoopUnswitch already does for the same reason) and
rely on callbacks to deal with deleted blocks.
Differential Revision: https://reviews.llvm.org/D99843
After loop interchange, the (old) outer loop header should not jump to
the `LoopExit`. Note that the old outer loop becomes the new inner loop
after interchange. If we branched to `LoopExit` then after interchange
we would jump directly from the (new) inner loop header to `LoopExit`
without executing the rest of outer loop.
This patch modifies adjustLoopBranches() such that the old outer
loop header (which becomes the new inner loop header) jumps to the
old inner loop latch which becomes the new outer loop latch after
interchange.
Reviewed By: bmahjour
Differential Revision: https://reviews.llvm.org/D98475
During LoopStrengthReduce, some of the SSA values that are used by debug values
may be lost and/or salvaged. After LSR we attempt to recover any undef debug
values, including any that were salvaged but then lost their values afterwards,
by replacing the lost values with any live equal values (plus a possible
constant offset) that have been gathered prior to running LSR. When we do this
we restore the debug value's original DIExpression, to undo any salvaging (as we
have gone back to using the original debug value).
This process can currently produce invalid debug info if the number of operands
has changed by salvaging during LSR. Replacing old values during the
applyEqualValues step does not change the number of location operands, which
means that when we restore the old DIExpression we may have a mismatch between
the number of operands used by the debug value and the number of operands
referenced by the DIExpression. This patch fixes this by restoring the full
original location metadata at the start of the applyEqualValues step, so that
there is no mismatch in operand count between the debug value and its
DIExpression.
Differential Revision: https://reviews.llvm.org/D98644
After loop interchange, the (old) outer loop header should not jump to
`LoopExit`. Note that the old outer loop becomes the new inner loop
after interchange. If we branched to `LoopExit` then after interchange
we would jump directly from the (new) inner loop header to `LoopExit`
without executing the rest of (new) outer loop.
This patch modifies adjustLoopBranches() such that the old outer
loop header (which becomes the new inner loop header) jumps to the
old inner loop latch which becomes the new outer loop latch after
interchange.
Reviewed By: bmahjour
Differential Revision: https://reviews.llvm.org/D98475
-Make sure of the CreateShl/LShr/AShr methods that take a uint64_t
instead of creating a ConstantInt for 1 ourselves.
-Use Builder.getInt1 or ConstantInt::getBool instead of a conditional.
-Pull out repeated calls to getType.
Follow up to a6d2a8d6f5. These were found by simply grepping for "::assume", and are the subset of that result which looked cleaner to me using the isa/dyn_cast patterns.
Follow up to a6d2a8d6f5. This covers all the public interfaces of the bundle related code. I tried to cleanup the internals where the changes were obvious, but there's definitely more room for improvement.
Add the subclass, update a few places which check for the intrinsic to use idiomatic dyn_cast, and update the public interface of AssumptionCache to use the new class. A follow up change will do the same for the newer assumption query/bundle mechanisms.
performScalarPREInsertion() inserts instructions into blocks that we
need to tell ImplicitControlFlowTracking about, otherwise the ICF cache
may be invalid.
Fixes PR49193.
Reviewed By: nikic
Differential Revision: https://reviews.llvm.org/D99909
The key change (4f5e92c) to switch gc.result and gc.relocate to being readnone landed nearly two weeks ago, and we haven't seen any fallout. Time to remove the code added to make reverting easy.
When we are able to SROA an alloca, we know all uses of it, meaning we
don't have to preserve the invariant group intrinsics and metadata.
It's possible that we could lose information regarding redundant
loads/stores, but that's unlikely to have any real impact since right
now the only user is Clang and vtables.
Reviewed By: rnk
Differential Revision: https://reviews.llvm.org/D99760
When run under valgrind, or with a malloc that poisons freed memory,
this can lead to segfaults or other problems.
To avoid modifying the AdditionalUsers DenseMap while still iterating,
save the instructions to be notified in a separate SmallPtrSet, and use
this to later call OperandChangedState on each instruction.
Fixes PR49582.
Reviewed By: fhahn
Differential Revision: https://reviews.llvm.org/D98602
The safepoints being inserted exists to free memory, or coordinate with another thread to do so. Thus, we must strip any inferred attributes and reinfer them after the lowering.
I'm not aware of any active miscompiles caused by this, but since I'm working on strengthening inference of both and leveraging them in the optimization decisions, I figured a bit of future proofing was warranted.
Support reassociation for min/max. With that we should be able to transform min(min(a, b), c) -> min(min(a, c), b) if min(a, c) is already available.
Reviewed By: mkazantsev, lebedev.ri
Differential Revision: https://reviews.llvm.org/D88287
This is a patch to fix the bug in alignment calculation (see https://reviews.llvm.org/D90529#2619492).
Consider this code:
```
call void @llvm.assume(i1 true) ["align"(i32* %a, i32 32, i32 28)]
%arrayidx = getelementptr inbounds i32, i32* %a, i64 -1
; aligment of %arrayidx?
```
The llvm.assume guarantees that `%a - 28` is 32-bytes aligned, meaning that `%a` is 32k + 28 for some k.
Therefore `a - 4` cannot be 32-bytes aligned but the existing code was calculating the pointer as 32-bytes aligned.
The reason why this happened is as follows.
`DiffSCEV` stores `%arrayidx - %a` which is -4.
`OffSCEV` stores the offset value of “align”, which is 28.
`DiffSCEV` + `OffSCEV` = 24 should be used for `a - 4`'s offset from 32k, but `DiffSCEV` - `OffSCEV` = 32 was being used instead.
Reviewed By: Tyker
Differential Revision: https://reviews.llvm.org/D98759
The code is assuming that having an exact exit count for the loop implies that exit counts for every exit are known. This used to be true, but when we added handling for dead exits we broke this invariant. The new invariant is that an exact loop count implies that any exits non trivially dead have exit counts.
We could have fixed this by either a) explicitly checking for a dead exit, or b) just testing for SCEVCouldNotCompute. I chose the second as it was simpler.
(Debugging this took longer than it should have since I'd mistyped the original assert and it wasn't checking what it was meant to...)
p.s. Sorry for the lack of test case. Getting things into a state to actually hit this is difficult and fragile. The original repro involves loop-deletion leaving SCEV in a slightly inprecise state which lets us bypass other transforms in IndVarSimplify on the way to this one. All of my attempts to separate it into a standalone test failed.
Removes CFGAnalyses from the preserved analyses set
returned by LoopFlattenPass::run().
Reviewed By: Dave Green, Ta-Wei Tu
Differential Revision: https://reviews.llvm.org/D99700
Name GVN uses name 'LI' for two different unrelated things:
LoadInst and LoopInfo. This patch relates the variables with
former meaning into 'Load' to disambiguate the code.
Before this change, the `llvm.access.group` metadata was dropped
when moving a load instruction in GVN. This prevents vectorizing
a C/C++ loop with `#pragma clang loop vectorize(assume_safety)`.
This change propagates the metadata as well as other metadata if
it is safe (the move-destination basic block and source basic
block belong to the same loop).
Differential Revision: https://reviews.llvm.org/D93503
This fixes the miscompilation reported in https://reviews.llvm.org/rG5bb38e84d3d0#986154 .
`select _, true, false` matches both m_LogicalAnd and m_LogicalOr, making later
transformations confused.
Simplify the branch condition to not have the form.
Unswitching a loop on a non-trivial divergent branch is expensive
since it serializes the execution of both version of the
loop. But identifying a divergent branch needs divergence analysis,
which is a function level analysis.
The legacy pass manager handles this dependency by isolating such a
loop transform and rerunning the required function analyses. This
functionality is currently missing in the new pass manager, and there
is no safe way for the SimpleLoopUnswitch pass to depend on
DivergenceAnalysis. So we conservatively assume that all non-trivial
branches are divergent if the target has divergence.
Reviewed By: tra
Differential Revision: https://reviews.llvm.org/D98958
This is yet another attempt to fix tightlyNested().
Add checks in tightlyNested() for the inner loop exit block,
such that 1) if there is control-flow divergence in between the inner
loop exit block and the outer loop latch, or 2) if the inner loop exit
block contains unsafe instructions, tightlyNested() returns false.
The reasoning behind is that after interchange, the original inner loop
exit block, which was part of the outer loop, would be put into the new
inner loop, and will be executed different number of times before and
after interchange. Thus it should be dealt with appropriately.
Reviewed By: Whitney
Differential Revision: https://reviews.llvm.org/D98263
LICM can sink instructions that have uses inside the loop, as
long as these uses are considered "free". However, if there were
only free uses inside the loop, and no uses outside the loop at
all, the instruction would still count towards the NumSunk
statistic. This resulted in a wild inflation of the NumSunk metric.
After this patch it drops down from 1141787 to 5852 on test-suite O3.
FindAvailableLoadedValue() relies on FindAvailablePtrLoadStore() to run
the alias analysis when searching for an equivalent value. However,
FindAvailablePtrLoadStore() calls the alias analysis framework with a
memory location for the load constructed from an address and a size,
which thus lacks TBAA metadata info. This commit modifies
FindAvailablePtrLoadStore() to accept an optional memory location as
parameter to allow FindAvailableLoadedValue() to create it based on the
load instruction, which would then have TBAA metadata info attached.
Reviewed By: nikic
Differential Revision: https://reviews.llvm.org/D99206
This patch changes the interface to take a RegisterKind, to indicate
whether the register bitwidth of a scalar register, fixed-width vector
register, or scalable vector register must be returned.
Reviewed By: paulwalker-arm
Differential Revision: https://reviews.llvm.org/D98874
The `InductionPHI` is not necessarily the increment instruction, as
demonstrated in pr49571.ll.
This patch removes the assertion and instead bails out from the
`LoopFlatten` pass if that happens.
This fixes https://bugs.llvm.org/show_bug.cgi?id=49571
Reviewed By: SjoerdMeijer
Differential Revision: https://reviews.llvm.org/D99252
The summary remarks are generated on a per-function basis. Using the
first instruction's location is sub-optimal for 2 reasons:
1. Sometimes the first instruction is missing !dbg
2. The location of the first instruction may be mis-leading.
Instead, just use the location of the function directly.
meetBDVState utility may sets the base pointer for the conflict state.
At this moment the base for conflict state does not have any meaning but
is used in comparison of BDV states. This comparison is used as an indicator
of progress done on iteration and RS4GC pass uses infinite loop to reach
fixed point.
As a result for added test on each iteration state for some phi nodes is updated
with other base value for conflict state and it indicates as a progress while
for conflict state there is no any progress more possible.
In reality the base value is transferred from one state to another and pass
detects the progress on these states.
The test is very fragile. The traversal order of states and operands of phi nodes
plays important role.
Reviewers: reames, dantrushin
Reviewed By: reames
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D99058
This is no-functional-change intended (NFC), but needed to allow
optimizer passes to use the API. See D98898 for a proposed usage
by SimplifyCFG.
I'm simplifying the code by removing the cl::opt. That was added
back with the original commit in D19488, but I don't see any
evidence in regression tests that it was used. Target-specific
overrides can use the usual patterns to adjust as necessary.
We could also restore that cl::opt, but it was not clear to me
exactly how to do it in the convoluted TTI class structure.
08196e0b2e exposed LowerExpectIntrinsic's
internal implementation detail in the form of
LikelyBranchWeight/UnlikelyBranchWeight options to the outside.
While this isn't incorrect from the results viewpoint,
this is suboptimal from the layering viewpoint,
and causes confusion - should transforms also use those weights,
or should they use something else, D98898?
So go back to status quo by making LikelyBranchWeight/UnlikelyBranchWeight
internal again, and fixing all the code that used it directly,
which currently is only clang codegen, thankfully,
to emit proper @llvm.expect intrinsics instead.
Upon reviewing D98898 i've come to realization that these are
implementation detail of LowerExpectIntrinsicPass,
and they should not be exposed to outside of it.
This reverts commit ee8b53815d.
This makes the settings available for use in other passes by housing
them within the Support lib, but NFC otherwise.
See D98898 for the proposed usage in SimplifyCFG
(where this change was originally included).
Differential Revision: https://reviews.llvm.org/D98945
All loop passes should preserve all analyses in LoopAnalysisResults. Add
checks for those when the checks are enabled (which is by default with
expensive checks on).
Note that due to PR44815, we don't check LAR's ScalarEvolution.
Apparently calling SE.verify() can change its results.
This is a reland of https://reviews.llvm.org/D98820 which was reverted
due to unacceptably large compile time regressions in normal debug
builds.
All loop passes should preserve all analyses in LoopAnalysisResults. Add
checks for those.
Note that due to PR44815, we don't check LAR's ScalarEvolution.
Apparently calling SE.verify() can change its results.
Only verify MSSA when VerifyMemorySSA, normally it's very expensive.
Reviewed By: asbirlea
Differential Revision: https://reviews.llvm.org/D98820
All loop passes should preserve all analyses in LoopAnalysisResults. Add
checks for those.
Note that due to PR44815, we don't check LAR's ScalarEvolution.
Apparently calling SE.verify() can change its results.
Reviewed By: asbirlea
Differential Revision: https://reviews.llvm.org/D98805
Fangrui Song