| Commit message (Collapse) | Author | Age | Files | Lines |
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Since D17854 LinkerSubsectionsViaSymbols is unnecessary.
It is interfering with ThinLTO implementation of CFI-ICall, where
the aliases used on the !LinkerSubsectionsViaSymbols branch are
needed to export jump tables to ThinLTO backends.
llvm-svn: 304582
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Differential Revision: https://reviews.llvm.org/D33805
llvm-svn: 304578
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constant
llvm-svn: 304562
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null, (inttoptr x) as well as it handles icmp (inttoptr x), null
Summary:
The constant folding code currently assumes that the constant expression will always be on the left and the simple null will be on the right. But that's not true at least on the path from InstSimplify.
This patch adds support to ConstantFolding to detect the reversed case.
Reviewers: spatel, dberlin, majnemer, davide, joey
Reviewed By: joey
Subscribers: joey, llvm-commits
Differential Revision: https://reviews.llvm.org/D33801
llvm-svn: 304559
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The existing test was not minimal, and there was no coverage
for the variants with a constant or vector types.
llvm-svn: 304555
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Summary:
Optimization passes may remove llvm.coro.suspend intrinsic while leaving matching llvm.coro.save intrinsic orphaned.
Make sure we clean up orphaned coro.saves. The bug manifested with a crash similar to this:
```
llvm_unreachable("Unknown type!");
llvm::MVT::getVT (Ty=0x489518, HandleUnknown=false)
llvm::EVT::getEVT
llvm::TargetLoweringBase::getValueType
llvm::ComputeValueVTs
llvm::SelectionDAGBuilder::visitTargetIntrinsic
```
Reviewers: GorNishanov
Subscribers: EricWF, llvm-commits
Differential Revision: https://reviews.llvm.org/D33817
llvm-svn: 304518
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builtin_expect applied on && or || expressions were not
handled properly before. With this patch, the problem is fixed.
Differential Revision: http://reviews.llvm.org/D33164
llvm-svn: 304517
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Summary: The flag -reverse-iterate is present only on +Asserts builds.
Reviewers: dberlin, davide, RKSimon, efriedma, chapuni
Reviewed By: efriedma, chapuni
Subscribers: chapuni, llvm-commits
Differential Revision: https://reviews.llvm.org/D33795
llvm-svn: 304498
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(icmp eq null, inttoptr x) when the null is on the left hand side. NFC
llvm-svn: 304474
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The added test case is to check whether the simplified value is passed to
getGEPCost().
Differential Revision: https://reviews.llvm.org/D33779
llvm-svn: 304454
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The lowerer wrongly assumes the ICMP instruction
1) always has a constant operand;
2) the operand has value 0.
It also assumes the expected value can only be one, thus
other values other than one will be considered 'zero'.
This leads to wrong profile annotation when other integer values
are used other than 0, 1 in the comparison or in the expect intrinsic.
Also missing is handling of equal predicate.
This patch fixes all the above problems.
Differential Revision: http://reviews.llvm.org/D33757
llvm-svn: 304453
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This allows us to collect profile statistics to tune static
branch prediction.
Differential Revision: http://reviews.llvm.org/D33746
llvm-svn: 304452
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iterating SmallPtrSet
Summary:
Sort OpsToRename before iterating to make iteration order deterministic.
Thanks to Daniel Berlin for the sorting logic.
Reviewers: dberlin, RKSimon, efriedma, davide
Reviewed By: dberlin, davide
Subscribers: sanjoy, davide, llvm-commits
Differential Revision: https://reviews.llvm.org/D33265
llvm-svn: 304447
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Summary: Also see D33429 for other ThinLTO + New PM related changes.
Reviewers: davide, chandlerc, tejohnson
Subscribers: mehdi_amini, Prazek, cfe-commits, inglorion, llvm-commits, eraman
Differential Revision: https://reviews.llvm.org/D33525
llvm-svn: 304378
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Differential Revision: http://reviews.llvm.org/D33694
llvm-svn: 304375
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investigating.
llvm-svn: 304350
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This reverts commit r304310.
It caused build failures in polly and mingw
due to undefined reference to
llvm::RTLIB::getMEMCPY_ELEMENT_ATOMIC.
llvm-svn: 304315
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Summary:
Expanding the loop idiom test for memcpy to also recognize unordered atomic memcpy.
The only difference for recognizing
an unordered atomic memcpy and instead of a normal memcpy is
that the loads and/or stores involved are unordered atomic operations.
Background: http://lists.llvm.org/pipermail/llvm-dev/2017-May/112779.html
Patch by Daniel Neilson!
Reviewers: reames, anna, skatkov
Reviewed By: reames
Subscribers: llvm-commits, mzolotukhin
Differential Revision: https://reviews.llvm.org/D33243
llvm-svn: 304310
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generate a phi of ops, which we don't currently support.
llvm-svn: 304272
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llvm-svn: 304271
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region.
Differential Revision: http://reviews.llvm.org/D33618
llvm-svn: 304245
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r303763 caused build failures in some out-of-tree tests due to an assertion in
TTI. The original patch updated cost estimates for induction variable update
instructions marked for scalarization. However, it didn't consider that the
incoming value of an induction variable phi node could be a cast instruction.
This caused queries for cast instruction costs with a mix of vector and scalar
types. This patch includes a fix for cast instructions and the test case from
PR33193.
The fix was suggested by Jonas Paulsson <paulsson@linux.vnet.ibm.com>.
Reference: https://bugs.llvm.org/show_bug.cgi?id=33193
Original Differential Revision: https://reviews.llvm.org/D33457
llvm-svn: 304235
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instructions after cttz/ctlz/ctpop where some bits of the input is known.
llvm-svn: 304224
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llvm-svn: 304179
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Summary:
I believe https://reviews.llvm.org/rL302576 introduced two bugs:
1) it produces duplicate distinct variables for every: dbg.value describing the same variable.
To fix the problme I switched form getDistinct() to get() in DebugLoc.cpp: auto reparentVar = [&](DILocalVariable *Var) {
return DILocalVariable::getDistinct(
2) It passes NewFunction plain name as a linkagename parameter to Subprogram constructor. Breaks assert in:
|| DeclLinkageName.empty()) || LinkageName == DeclLinkageName) && "decl has a linkage name and it is different"' failed.
#9 0x00007f5010261b75 llvm::DwarfUnit::applySubprogramDefinitionAttributes(llvm::DISubprogram const*, llvm::DIE&) /home/gor/llvm/lib/CodeGen/AsmPrinter/DwarfUnit.cpp:1173:3
#
(Edit: reproducer added)
Here how https://reviews.llvm.org/rL302576 broke coroutine debug info.
Coroutine body of the original function is split into several parts by cloning and removing unneeded code.
All parts describe the original function and variables present in the original function.
For a simple case, prior to Split, original function has these two blocks:
```
PostSpill: ; preds = %AllocaSpillBB
call void @llvm.dbg.value(metadata i32 %x, i64 0, metadata !14, metadata !15), !dbg !13
store i32 %x, i32* %x.addr, align 4
...
and
sw.epilog: ; preds = %sw.bb
%x.addr.reload.addr = getelementptr inbounds %f.Frame, %f.Frame* %FramePtr, i32 0, i32 4, !dbg !20
%4 = load i32, i32* %x.addr.reload.addr, align 4, !dbg !20
call void @llvm.dbg.value(metadata i32 %4, i64 0, metadata !14, metadata !15), !dbg !13
!14 = !DILocalVariable(name: "x", arg: 1, scope: !6, file: !7, line: 55, type: !11)
```
Note that in two blocks different expression represent the same original user variable X.
Before rL302576, for every cloned function there was exactly one cloned DILocalVariable(name: "x" as in:
```
define i8* @f(i32 %x) #0 !dbg !6 {
...
!6 = distinct !DISubprogram(name: "f", scope: !7, file: !7, line: 55, type: !8, isLocal: false, isDefinition: true, scopeLine: 55, flags: DIFlagPrototyped,
...
!14 = !DILocalVariable(name: "x", arg: 1, scope: !6, file: !7, line: 55, type: !11)
define internal fastcc void @f.resume(%f.Frame* %FramePtr) #0 !dbg !25 {
...
!25 = distinct !DISubprogram(name: "f", scope: !7, file: !7, line: 55, type: !8, isLocal: false, isDefinition: true, scopeLine: 55, flags: DIFlagPrototyped, isOptimized: false, unit: !0, variables: !2)
!28 = !DILocalVariable(name: "x", arg: 1, scope: !25, file: !7, line: 55, type: !11)
```
After rL302576, for every cloned function there were as many DILocalVariable(name: "x" as there were "call void @llvm.dbg.value" for that variable.
This was causing asserts in VerifyDebugInfo and AssemblyPrinter.
Example:
```
!27 = distinct !DISubprogram(name: "f", linkageName: "f.resume", scope: !7, file: !7, line: 55, type: !8, isLocal: false, isDefinition: true, scopeLine: 55,
!29 = distinct !DILocalVariable(name: "x", arg: 1, scope: !27, file: !7, line: 55, type: !11)
!39 = distinct !DILocalVariable(name: "x", arg: 1, scope: !27, file: !7, line: 55, type: !11)
!41 = distinct !DILocalVariable(name: "x", arg: 1, scope: !27, file: !7, line: 55, type: !11)
```
Second problem:
Prior to rL302576, all clones were described by DISubprogram referring to original function.
```
define i8* @f(i32 %x) #0 !dbg !6 {
...
!6 = distinct !DISubprogram(name: "f", scope: !7, file: !7, line: 55, type: !8, isLocal: false, isDefinition: true, scopeLine: 55, flags: DIFlagPrototyped,
define internal fastcc void @f.resume(%f.Frame* %FramePtr) #0 !dbg !25 {
...
!25 = distinct !DISubprogram(name: "f", scope: !7, file: !7, line: 55, type: !8, isLocal: false, isDefinition: true, scopeLine: 55, flags: DIFlagPrototyped,
```
After rL302576, DISubprogram for clones is of two minds, plain name refers to the original name, linkageName refers to plain name of the clone.
```
!27 = distinct !DISubprogram(name: "f", linkageName: "f.resume", scope: !7, file: !7, line: 55, type: !8, isLocal: false, isDefinition: true, scopeLine: 55,
```
I think the assumption in AsmPrinter is that both name and linkageName should refer to the same entity. It asserts here when they are not:
```
|| DeclLinkageName.empty()) || LinkageName == DeclLinkageName) && "decl has a linkage name and it is different"' failed.
#9 0x00007f5010261b75 llvm::DwarfUnit::applySubprogramDefinitionAttributes(llvm::DISubprogram const*, llvm::DIE&) /home/gor/llvm/lib/CodeGen/AsmPrinter/DwarfUnit.cpp:1173:3
```
After this fix, behavior (with respect to coroutines) reverts to exactly as it was before and therefore making them debuggable again, or even more importantly, compilable, with "-g"
Reviewers: dblaikie, echristo, aprantl
Reviewed By: dblaikie
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D33614
llvm-svn: 304079
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Summary:
This fixes introduction of an incorrect inttoptr/ptrtoint pair in
the included test case which makes use of non-integral pointers. I
suspect there are more cases like this left, but this takes care of
the one I was seeing at the moment.
Reviewers: sanjoy
Subscribers: mzolotukhin, llvm-commits
Differential Revision: https://reviews.llvm.org/D33129
llvm-svn: 304058
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The recommit is to fix a bug about ExtractValue and InsertValue ops. For those
ops, some varargs inside GVN::Expression are not value numbers but raw index
numbers. It is wrong to do phi-translate for raw index numbers, and the fix is
to stop doing that.
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
llvm-svn: 304050
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C2) handling in order to support splat vectors.
The tests here are have operands commuted to provide more coverage. I also commuted one of the instructions in the scalar tests so the 4 tests cover the 4 commuted variations
Differential Revision: https://reviews.llvm.org/D33599
llvm-svn: 304021
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The patch rL303730 was reverted because test lsr-expand-quadratic.ll failed on
many non-X86 configs with this patch. The reason of this is that the patch
makes a correctless fix that changes optimizer's behavior for this test.
Without the change, LSR was making an overconfident simplification basing on a
wrong SCEV. Apparently it did not need the IV analysis to do this. With the
change, it chose a different way to simplify (that wasn't so confident), and
this way required the IV analysis. Now, following the right execution path,
LSR tries to make a transformation relying on IV Users analysis. This analysis
is target-dependent due to this code:
// LSR is not APInt clean, do not touch integers bigger than 64-bits.
// Also avoid creating IVs of non-native types. For example, we don't want a
// 64-bit IV in 32-bit code just because the loop has one 64-bit cast.
uint64_t Width = SE->getTypeSizeInBits(I->getType());
if (Width > 64 || !DL.isLegalInteger(Width))
return false;
To make a proper transformation in this test case, the type i32 needs to be
legal for the specified data layout. When the test runs on some non-X86
configuration (e.g. pure ARM 64), opt gets confused by the specified target
and does not use it, rejecting the specified data layout as well. Instead,
it uses some default layout that does not treat i32 as a legal type
(currently the layout that is used when it is not specified does not have
legal types at all). As result, the transformation we expect to happen does
not happen for this test.
This re-enabling patch does not have any source code changes compared to the
original patch rL303730. The only difference is that the failing test is
moved to X86 directory and now has requirement of running on x86 only to comply
with the specified target triple and data layout.
Differential Revision: https://reviews.llvm.org/D33543
llvm-svn: 303971
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llvm-svn: 303969
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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
llvm-svn: 303923
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Fix PR33120 and others by eliminating self-cycles a different way.
llvm-svn: 303875
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Reviewed By: reames
Differential Revision: https://reviews.llvm.org/D28565
llvm-svn: 303870
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There's probably a lot more like this (see also comments in D33338 about responsibility),
but I suspect we don't usually get a visible manifestation.
Given the recent interest in improving InstCombine efficiency, another potential micro-opt
that could be repeated several times in this function: morph the existing icmp pred/operands
instead of creating a new instruction.
llvm-svn: 303860
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This patch provides an initial prototype for a pass that sinks instructions based on GVN information, similar to GVNHoist. It is not yet ready for commiting but I've uploaded it to gather some initial thoughts.
This pass attempts to sink instructions into successors, reducing static
instruction count and enabling if-conversion.
We use a variant of global value numbering to decide what can be sunk.
Consider:
[ %a1 = add i32 %b, 1 ] [ %c1 = add i32 %d, 1 ]
[ %a2 = xor i32 %a1, 1 ] [ %c2 = xor i32 %c1, 1 ]
\ /
[ %e = phi i32 %a2, %c2 ]
[ add i32 %e, 4 ]
GVN would number %a1 and %c1 differently because they compute different
results - the VN of an instruction is a function of its opcode and the
transitive closure of its operands. This is the key property for hoisting
and CSE.
What we want when sinking however is for a numbering that is a function of
the *uses* of an instruction, which allows us to answer the question "if I
replace %a1 with %c1, will it contribute in an equivalent way to all
successive instructions?". The (new) PostValueTable class in GVN provides this
mapping.
This pass has some shown really impressive improvements especially for codesize already on internal benchmarks, so I have high hopes it can replace all the sinking logic in SimplifyCFG.
Differential revision: https://reviews.llvm.org/D24805
llvm-svn: 303850
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instrumenting code.
This is important in the new pass manager. The old pass manager's
inliner has a small DCE routine embedded within it. The new pass manager
relies on the actual GlobalDCE pass for this.
Without this patch, instrumentation profiling with the new PM results in
massive code bloat in the object files because the instrumentation
itself ends up preventing DCE from working to remove the code.
We should probably change the instrumentation (and/or DCE) so that we
can eliminate dead code even if instrumented, but we shouldn't even
spend the time generating instrumentation for that code so this still
seems like a good patch.
Differential Revision: https://reviews.llvm.org/D33535
llvm-svn: 303845
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pass.
The original logic only considered direct successors of the hoisted
domtree nodes, but that isn't really enough. If there are other basic
blocks that are completely within the subtree, their successors could
just as easily be impacted by the hoisting.
The more I think about it, the more I think the correct update here is
to hoist every block on the dominance frontier which has an idom in the
chain we hoist across. However, this is subtle enough that I'd
definitely appreciate some more eyes on it.
Sadly, if this is the correct algorithm, it requires computing a (highly
localized) dominance frontier. I've done this in the simplest (IE, least
code) way I could come up with, but that may be too naive. Suggestions
welcome here, dominance update algorithms are not an area I've studied
much, so I don't have strong opinions.
In good news, with this patch, turning on simple unswitch passes the
LLVM test suite for me with asserts enabled.
Differential Revision: https://reviews.llvm.org/D32740
llvm-svn: 303843
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Summary:
Frontend generates store instructions after allocas, for example:
```
define i8* @f(i64 %this) "coroutine.presplit"="1" personality i32 0 {
entry:
%this.addr = alloca i64
store i64 %this, i64* %this.addr
..
%hdl = call i8* @llvm.coro.begin(token %id, i8* %alloc)
```
Such instructions may require spilling into coro.frame, but, coro-frame address is only available after coro.begin and thus needs to be moved after coro.begin.
The only instructions that should not be moved are the arguments of coro.begin and all of their operands.
Reviewers: GorNishanov, majnemer
Reviewed By: GorNishanov
Subscribers: llvm-commits, EricWF
Differential Revision: https://reviews.llvm.org/D33527
llvm-svn: 303825
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Reviewers: majnemer
Subscribers: EricWF, llvm-commits
Differential Revision: https://reviews.llvm.org/D33524
llvm-svn: 303819
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The swapped operands in the first test is a manifestation of an
inefficiency for vectors that doesn't exist for scalars because
the IRBuilder checks for an all-ones mask for scalars, but not
vectors.
llvm-svn: 303818
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llvm-svn: 303816
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llvm-svn: 303808
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the Zero or Undef is on the LHS.
Summary: This code was migrated from InstCombine a few years ago. InstCombine had nearby code that would move Constants to the RHS for these, but InstSimplify doesn't have such code on this path.
Reviewers: spatel, majnemer, davide
Reviewed By: spatel
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D33473
llvm-svn: 303774
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For non-uniform instructions marked for scalarization, we should update
`VectorTy` when computing instruction costs to reflect the scalar type. In
addition to determining instruction costs, this type is also used to signal
that all instructions in the loop will be scalarized. This currently affects
memory instructions and non-pointer induction variables and their updates. (We
also mark GEPs scalar after vectorization, but their cost is computed together
with memory instructions.) For scalarized induction updates, this patch also
scales the scalar cost by the vectorization factor, corresponding to each
induction step.
llvm-svn: 303763
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As noted in https://bugs.llvm.org/show_bug.cgi?id=33138 and
the comments, there are multiple ways to view this. If we
choose not to solve this in InstCombine, these tests will
serve as documentation of that choice.
llvm-svn: 303755
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The solution for PR26702 ( https://bugs.llvm.org/show_bug.cgi?id=26702 )
added a canonicalization rule, but the minimal regression tests don't
demonstrate how that rule interacts with other folds.
llvm-svn: 303750
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This reverts commit r303730 because it broke all the buildbots.
llvm-svn: 303747
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The loop vectorizer usually vectorizes any instruction it can and then
extracts the elements for a scalarized use. On SystemZ, all elements
containing addresses must be extracted into address registers (GRs). Since
this extraction is not free, it is better to have the address in a suitable
register to begin with. By forcing address arithmetic instructions and loads
of addresses to be scalar after vectorization, two benefits result:
* No need to extract the register
* LSR optimizations trigger (LSR isn't handling vector addresses currently)
Benchmarking show improvements on SystemZ with this new behaviour.
Any other target could try this by returning false in the new hook
prefersVectorizedAddressing().
Review: Renato Golin, Elena Demikhovsky, Ulrich Weigand
https://reviews.llvm.org/D32422
llvm-svn: 303744
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When folding arguments of AddExpr or MulExpr with recurrences, we rely on the fact that
the loop of our base recurrency is the bottom-lost in terms of domination. This assumption
may be broken by an expression which is treated as invariant, and which depends on a complex
Phi for which SCEVUnknown was created. If such Phi is a loop Phi, and this loop is lower than
the chosen AddRecExpr's loop, it is invalid to fold our expression with the recurrence.
Another reason why it might be invalid to fold SCEVUnknown into Phi start value is that unlike
other SCEVs, SCEVUnknown are sometimes position-bound. For example, here:
for (...) { // loop
phi = {A,+,B}
}
X = load ...
Folding phi + X into {A+X,+,B}<loop> actually makes no sense, because X does not exist and cannot
exist while we are iterating in loop (this memory can be even not allocated and not filled by this moment).
It is only valid to make such folding if X is defined before the loop. In this case the recurrence {A+X,+,B}<loop>
may be existant.
This patch prohibits folding of SCEVUnknown (and those who use them) into the start value of an AddRecExpr,
if this instruction is dominated by the loop. Merging the dominating unknown values is still valid. Some tests that
relied on the fact that some SCEVUnknown should be folded into AddRec's are changed so that they no longer
expect such behavior.
llvm-svn: 303730
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Otherwise we don't revisit an instruction that could be simplified,
and when we verify, we discover there's something that changed, i.e.
what we had wasn't a maximal fixpoint.
Fixes PR32836.
llvm-svn: 303715
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