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r288433 | oranevskyy | 2016-12-01 14:58:35 -0800 (Thu, 01 Dec 2016) | 24 lines
[ARM] Fix for 64-bit CAS expansion on ARM32 with -O0
Summary:
This patch fixes comparison of 64-bit atomic with its expected value in CMP_SWAP_64 expansion.
Currently, the low words are compared with CMP, while the high words are compared with SBC. SBC expects the carry flag to be set if CMP detects a difference. CMP might leave the carry unset for unequal arguments though if the first one is >= than the second. This might cause the comparison logic to detect false equality.
Example of the broken C++ code:
```
std::atomic<long long> at(2);
long long ll = 1;
std::atomic_compare_exchange_strong(&at, &ll, 3);
```
Even though the atomic `at` and the expected value `ll` are not equal and `atomic_compare_exchange_strong` returns `false`, `at` is changed to 3.
The patch replaces SBC with CMPEQ.
Reviewers: t.p.northover
Subscribers: aemerson, rengolin, llvm-commits, asl
Differential Revision: https://reviews.llvm.org/D27315
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r288418 | tnorthover | 2016-12-01 13:31:59 -0800 (Thu, 01 Dec 2016) | 13 lines
AArch64: fix 128-bit cmpxchg at -O0 (again, again).
This time the issue is fortunately just a simple mistake rather than a horrible
design spectre. I thought SUBS/SBCS provided sufficient NZCV flags for
comparing two 64-bit values, but they don't.
The fix is slightly clunkier in AArch64 because we can't use conditional
execution to emit a pair of CMPs. Traditionally an "icmp ne i128" would map to
an EOR/EOR/ORR/CBNZ, but that uses more registers so it's easier to go with a
CSET/CINC/CBNZ combination. Slightly less efficient, but this is -O0 anyway.
Thanks to Anton Korobeynikov for pointing out the issue.
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r277755 | tnorthover | 2016-08-04 12:32:28 -0700 (Thu, 04 Aug 2016) | 5 lines
AArch64: don't assume all i128s are BUILD_PAIRs
It leads to a crash when they're not. I'm *sure* I've made this mistake before,
at least once.
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r278268 | nhaehnle | 2016-08-10 11:51:14 -0700 (Wed, 10 Aug 2016) | 28 lines
LiveIntervalAnalysis: fix a crash in repairOldRegInRange
Summary:
See the new test case for one that was (non-deterministically) crashing
on trunk and deterministically hit the assertion that I added in D23302.
Basically, the machine function contains a sequence
DS_WRITE_B32 %vreg4, %vreg14:sub0, ...
DS_WRITE_B32 %vreg4, %vreg14:sub0, ...
%vreg14:sub1<def> = COPY %vreg14:sub0
and SILoadStoreOptimizer::mergeWrite2Pair merges the two DS_WRITE_B32
instructions into one before calling repairIntervalsInRange.
Now repairIntervalsInRange wants to repair %vreg14, in particular, and
ends up trying to repair %vreg14:sub1 as well, but that only becomes
active _after_ the range that is to be repaired, hence the crash due
to LR.find(...) == LR.begin() at the start of repairOldRegInRange.
I believe that just skipping those subrange is fine, but again, not too
familiar with that code.
Reviewers: MatzeB, kparzysz, tstellarAMD
Subscribers: llvm-commits, MatzeB
Differential Revision: https://reviews.llvm.org/D23303
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r287339 | nhaehnle | 2016-11-18 03:55:52 -0800 (Fri, 18 Nov 2016) | 20 lines
AMDGPU: Fix legalization of MUBUF instructions in shaders
Summary:
The addr64-based legalization is incorrect for MUBUF instructions with idxen
set as well as for BUFFER_LOAD/STORE_FORMAT_* instructions. This affects
e.g. shaders that access buffer textures.
Since we never actually need the addr64-legalization in shaders, this patch
takes the easy route and keys off the calling convention. If this ever
affects (non-OpenGL) compute, the type of legalization needs to be chosen
based on some TSFlag.
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=98664
Reviewers: arsenm, tstellarAMD
Subscribers: kzhuravl, wdng, yaxunl, tony-tye, llvm-commits
Differential Revision: https://reviews.llvm.org/D26747
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r280589 | nhaehnle | 2016-09-03 05:26:32 -0700 (Sat, 03 Sep 2016) | 19 lines
AMDGPU: Fix an interaction between WQM and polygon stippling
Summary:
This fixes a rare bug in polygon stippling with non-monolithic pixel shaders.
The underlying problem is as follows: the prolog part contains the polygon
stippling sequence, i.e. a kill. The main part then enables WQM based on the
_reduced_ exec mask, effectively undoing most of the polygon stippling.
Since we cannot know whether polygon stippling will be used, the main part
of a non-monolithic shader must always return to exact mode to fix this
problem.
Reviewers: arsenm, tstellarAMD, mareko
Subscribers: arsenm, llvm-commits, kzhuravl
Differential Revision: https://reviews.llvm.org/D23131
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r286998 | chfast | 2016-11-15 19:29:24 +0100 (wto, 15 lis 2016) | 12 lines
Integer legalization: fix MUL expansion
Summary:
This fixes the runtime results produces by the fallback multiplication expansion introduced in r270720.
For tests I created a fuzz tester that compares the results with Boost.Multiprecision.
Reviewers: hfinkel
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D26628
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r281403 | chfast | 2016-09-13 23:55:41 +0200 (wto, 13 wrz 2016) | 9 lines
[CodeGen] Fix invalid shift in mul expansion
Summary: When expanding mul in type legalization make sure the type for
shift amount can actually fit the value.
This fixes PR30354 https://llvm.org/bugs/show_bug.cgi?id=30354.
Reviewers: hfinkel, majnemer, RKSimon
Subscribers: RKSimon, llvm-commits
Differential Revision: https://reviews.llvm.org/D24478
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r283612 | davide | 2016-10-07 14:53:09 -0700 (Fri, 07 Oct 2016) | 5 lines
[InstCombine] Don't unpack arrays that are too large (part 2).
This is similar to r283599, but for store instructions.
Thanks to David for pointing out!
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r287353 | hans | 2016-11-18 09:33:05 -0800 (Fri, 18 Nov 2016) | 12 lines
IRMover: Avoid accidentally mapping types from the destination module (PR30799)
During Module linking, it's possible for SrcM->getIdentifiedStructTypes();
to return types that are actually defined in the destination module
(DstM). Depending on how the bitcode file was read,
getIdentifiedStructTypes() might do a walk over all values, including
metadata nodes, looking for types. In my case, a debug info metadata
node was shared between the two modules, and it referred to a type
defined in the destination module (see test case).
Differential Revision: https://reviews.llvm.org/D26212
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[X86] Do not use AND8ri8 in AVX512 pattern
This variant is (as documented in the TD) for disassembler use only, and should
not be used in patterns - it is longer, and is broken on 64-bit.
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r282182 | nemanja.i.ibm | 2016-09-22 12:06:38 -0700 (Thu, 22 Sep 2016) | 6 lines
[PowerPC] Sign extend sub-word values for atomic comparisons
Atomic comparison instructions use the sub-word load instruction on
Power8 and up but the value is not sign extended prior to the signed word
compare instruction. This patch adds that sign extension.
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r281479 | nemanja.i.ibm | 2016-09-14 07:19:09 -0700 (Wed, 14 Sep 2016) | 9 lines
Fix code-gen crash on Power9 for insert_vector_elt with variable index (PR30189)
This patch corresponds to review:
https://reviews.llvm.org/D24021
In the initial implementation of this instruction, I forgot to account for
variable indices. This patch fixes PR30189 and should probably be merged into
3.9.1 (I'll open a bug according to the new instructions).
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r279930 | elena.demikhovsky | 2016-08-28 01:53:53 -0700 (Sun, 28 Aug 2016) | 7 lines
[Loop Vectorizer] Fixed memory confilict checks.
Fixed a bug in run-time checks for possible memory conflicts inside loop.
The bug is in Low <-> High boundaries calculation. The High boundary
should be calculated as "last memory access pointer + element size".
Differential revision: https://reviews.llvm.org/D23176
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r280599 | mehdi.amini | 2016-09-03 14:12:33 -0700 (Sat, 03 Sep 2016) | 10 lines
Fix ThinLTO crash with debug info
Because the recent change about ODR type uniquing in the context,
we can reach types defined in another module during IR linking.
This triggered some assertions in case we IR link without starting
from an empty module. To alleviate that, we can self-map metadata
defined in the destination module so that they won't be visited.
Differential Revision: https://reviews.llvm.org/D23841
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To allow broadcast loads of a non-zero'th vector element, lowerVectorShuffleAsBroadcast can replace a load with a new load with an adjusted address, but unfortunately we weren't ensuring that the new load respected the same dependencies.
This patch adds a TokenFactor and updates all dependencies of the old load to reference the new load instead.
Bug found during internal testing.
Differential Revision: https://reviews.llvm.org/D25039
As discussed on PR30596
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r283129 | hans | 2016-10-03 11:18:04 -0700 (Mon, 03 Oct 2016) | 6 lines
Jump threading: avoid trying to split edge into landingpad block (PR27840)
Splitting the edge is nontrivial because of the landing pad, and we would
currently assert trying to do it.
Differential Revision: https://reviews.llvm.org/D24680
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r279647 | sanjoy | 2016-08-24 11:10:21 -0700 (Wed, 24 Aug 2016) | 5 lines
[SCCP] Don't delete side-effecting instructions
I'm not sure if the `!isa<CallInst>(Inst) &&
!isa<TerminatorInst>(Inst))` bit is correct either, but this fixes the
case we know is broken.
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r279268 | majnemer | 2016-08-19 09:37:40 -0700 (Fri, 19 Aug 2016) | 5 lines
[CloneFunction] Don't remove unrelated nodes from the CGSSC
CGSCC use a WeakVH to track call sites. RAUW a call within a function
can result in that WeakVH getting confused about whether or not the call
site is still around.
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r279125 | mssimpso | 2016-08-18 12:50:32 -0700 (Thu, 18 Aug 2016) | 14 lines
[SLP] Initialize VectorizedValue when gathering
We abort building vectorizable trees in some cases (e.g., if the maximum
recursion depth is reached, if the region size is too large, etc.). If this
happens for a reduction, we can be left with a root entry that needs to be
gathered. For these cases, we need make sure we actually set VectorizedValue to
the resulting vector.
This patch ensures we properly set VectorizedValue, and it also ensures the
insertelement sequence generated for the gathers is inserted at the correct
location.
Reference: https://llvm.org/bugs/show_bug.cgi?id=28330
Differential Revison: https://reviews.llvm.org/D23410
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r278343 | mssimpso | 2016-08-11 08:28:45 -0700 (Thu, 11 Aug 2016) | 1 line
[SLP] Make RecursionMaxDepth a command line option (NFC)
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r278938 | mcrosier | 2016-08-17 08:54:39 -0700 (Wed, 17 Aug 2016) | 5 lines
Revert "Reassociate: Reprocess RedoInsts after each inst".
This reverts commit r258830, which introduced a bug described in PR28367.
PR28367
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r278900 | cycheng | 2016-08-16 20:17:44 -0700 (Tue, 16 Aug 2016) | 12 lines
[ppc64] Don't apply sibling call optimization if callee has any byval arg
This is a quick work around, because in some cases, e.g. caller's stack
size > callee's stack size, we are still able to apply sibling call
optimization even callee has any byval arg.
This patch fix: https://llvm.org/bugs/show_bug.cgi?id=28328
Reviewers: hfinkel kbarton nemanjai amehsan
Subscribers: hans, tjablin
https://reviews.llvm.org/D23441
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r278571 | rnk | 2016-08-12 15:23:04 -0700 (Fri, 12 Aug 2016) | 6 lines
[Inliner] Don't treat inalloca allocas as static
They aren't static, and moving them to the entry block across something
else will only result in tears.
Root cause of http://crbug.com/636558.
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r278575 | haicheng | 2016-08-12 16:13:38 -0700 (Fri, 12 Aug 2016) | 6 lines
Reapply [BranchFolding] Restrict tail merging loop blocks after MBP
Fixed a bug in the test case.
To fix PR28104, this patch restricts tail merging to blocks that belong to the
same loop after MBP.
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I had to adjust the test as it wasn't passing on the branch, presumably
due to different machine block placement.
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r278584 | sanjoy | 2016-08-12 17:58:31 -0700 (Fri, 12 Aug 2016) | 15 lines
[IndVars] Ignore (s|z)exts that don't extend the induction variable
`IVVisitor::visitCast` used to have the invariant that if the
instruction it was passed was a sext or zext instruction, the result of
the instruction would be wider than the induction variable. This is no
longer true after rL275037, so this change teaches `IndVarSimplify` s
implementation of `IVVisitor::visitCast` to work with the relaxed
invariant.
A corresponding change to SimplifyIndVar to preserve the said invariant
after rL275037 would also work, but given how `IVVisitor::visitCast` is
spelled (no indication of said invariant), I figured the current fix is
cleaner.
Fixes PR28935.
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r278573 | timshen | 2016-08-12 15:47:13 -0700 (Fri, 12 Aug 2016) | 8 lines
[LoopVectorize] Detect loops in the innermost loop before creating InnerLoopVectorizer
InnerLoopVectorizer shouldn't handle a loop with cycles inside the loop
body, even if that cycle isn't a natural loop.
Fixes PR28541.
Differential Revision: https://reviews.llvm.org/D22952
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r277399 | timshen | 2016-08-01 15:32:20 -0700 (Mon, 01 Aug 2016) | 9 lines
[ADT] NFC: Generalize GraphTraits requirement of "NodeType *" in interfaces to "NodeRef", and migrate SCCIterator.h to use NodeRef
Summary: By generalize the interface, users are able to inject more flexible Node token into the algorithm, for example, a pair of vector<Node>* and index integer. Currently I only migrated SCCIterator to use NodeRef, but more is coming. It's a NFC.
Reviewers: dblaikie, chandlerc
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D22937
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r278157 | timshen | 2016-08-09 13:23:13 -0700 (Tue, 09 Aug 2016) | 7 lines
[ADT] Change iterator_adaptor_base's default template arguments to forward more underlying typedefs
Reviewers: chandlerc
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D23217
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r278569 | timshen | 2016-08-12 15:03:28 -0700 (Fri, 12 Aug 2016) | 3 lines
[ADT] Add filter_iterator for filtering elements
Differential Revision: https://reviews.llvm.org/D22951
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r278413 | gberry | 2016-08-11 14:05:17 -0700 (Thu, 11 Aug 2016) | 17 lines
[SCEV] Update interface to handle SCEVExpander insert point motion.
Summary:
This is an extension of the fix in r271424. That fix dealt with builder
insert points being moved by SCEV expansion, but only for the lifetime
of the expand call. This change modifies the interface so that LSR can
safely call expand multiple times at the same insert point and do the
right thing if one of the expansions decides to move the original insert
point.
This is a fix for PR28719.
Reviewers: sanjoy
Subscribers: llvm-commits, mcrosier, mzolotukhin
Differential Revision: https://reviews.llvm.org/D23342
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r276051 | arsenm | 2016-07-19 16:16:53 -0700 (Tue, 19 Jul 2016) | 8 lines
AMDGPU: Change fdiv lowering based on !fpmath metadata
If 2.5 ulp is acceptable, denormals are not required, and
isn't a reciprocal which will already be handled, replace
with a faster fdiv.
Simplify the lowering tests by using per function
subtarget features.
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r276823 | arsenm | 2016-07-26 16:25:44 -0700 (Tue, 26 Jul 2016) | 4 lines
AMDGPU: Use rcp for fdiv 1, x with fpmath metadata
Using rcp should be OK for safe math usually, so this
should not be replacing the original fdiv.
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r278002 | sbaranga | 2016-08-08 06:13:57 -0700 (Mon, 08 Aug 2016) | 18 lines
[AArch64] PR28877: Don't assume we're running after legalization when creating vcvtfp2fxs
Summary:
The DAG combine transformation that was generating the
aarch64_neon_vcvtfp2fxs node was assuming that all
inputs where legal and wasn't accounting that the input
could be a v4f64 if we're trying to do the transformation
before legalization. We now bail out in this case.
All illegal types besides v4f64 were already rejected.
Fixes https://llvm.org/bugs/show_bug.cgi?id=28877.
Reviewers: jmolloy
Subscribers: aemerson, rengolin, llvm-commits
Differential Revision: https://reviews.llvm.org/D23261
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r278086 | matze | 2016-08-08 18:47:26 -0700 (Mon, 08 Aug 2016) | 6 lines
X86InstrInfo: Update liveness in classifyLea()
We need to update liveness information when we create COPYs in
classifyLea().
This fixes http://llvm.org/28301
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r277691 | majnemer | 2016-08-03 21:24:02 -0700 (Wed, 03 Aug 2016) | 4 lines
Reinstate "[CloneFunction] Don't remove side effecting calls"
This reinstates r277611 + r277614 and reverts r277642. A cast_or_null
should have been a dyn_cast_or_null.
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r277693 | majnemer | 2016-08-03 21:47:18 -0700 (Wed, 03 Aug 2016) | 1 line
Forgot the dyn_cast_or_null intended for r277691.
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r277773 | majnemer | 2016-08-04 14:28:59 -0700 (Thu, 04 Aug 2016) | 6 lines
[CloneFunction] Add a testcase for r277691/r277693
PR28848 had a very nice reduction of the underlying cause of the bug.
Our ValueMap had, in an entry for an Instruction, a ConstantInt.
This is not at all unexpected but should be handled properly.
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r277625 | dexonsmith | 2016-08-03 11:19:43 -0700 (Wed, 03 Aug 2016) | 42 lines
IR: Drop uniquing when an MDNode Value operand is deleted
This is a fix for PR28697.
An MDNode can indirectly refer to a GlobalValue, through a
ConstantAsMetadata. When the GlobalValue is deleted, the MDNode operand
is reset to `nullptr`. If the node is uniqued, this can lead to a
hard-to-detect cache invalidation in a Metadata map that's shared across
an LLVMContext.
Consider:
1. A map from Metadata* to `T` called RemappedMDs.
2. A node that references a global variable, `!{i1* @GV}`.
3. Insert `!{i1* @GV} -> SomeT` in the map.
4. Delete `@GV`, leaving behind `!{null} -> SomeT`.
Looking up the generic and uninteresting `!{null}` gives you `SomeT`,
which is likely related to `@GV`. Worse, `SomeT`'s lifetime may be tied
to the deleted `@GV`.
This occurs in practice in the shared ValueMap used since r266579 in the
IRMover. Other code that handles more than one Module (with different
lifetimes) in the same LLVMContext could hit it too.
The fix here is a partial revert of r225223: in the rare case that an
MDNode operand is a ConstantAsMetadata (i.e., wrapping a node from the
Value hierarchy), drop uniquing if it gets replaced with `nullptr`.
This changes step #4 above to leave behind `distinct !{null} -> SomeT`,
which can't be confused with the generic `!{null}`.
In theory, this can cause some churn in the LLVMContext's MDNode
uniquing map when Values are being deleted. However:
- The number of GlobalValues referenced from uniqued MDNodes is
expected to be quite small. E.g., the debug info metadata schema
only references GlobalValues from distinct nodes.
- Other Constants have the lifetime of the LLVMContext, whose teardown
is careful to drop references before deleting the constants.
As a result, I don't expect a compile time regression from this change.
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r277504 | nha | 2016-08-02 12:31:14 -0700 (Tue, 02 Aug 2016) | 20 lines
AMDGPU: Stay in WQM for non-intrinsic stores
Summary:
Two types of stores are possible in pixel shaders: stores to memory that are
explicitly requested at the API level, and stores that are an implementation
detail of register spilling or lowering of arrays.
For the first kind of store, we must ensure that helper pixels have no effect
and hence WQM must be disabled. The second kind of store must always be
executed, because the written value may be loaded again in a way that is
relevant for helper pixels as well -- and there are no externally visible
effects anyway.
This is a candidate for the 3.9 release branch.
Reviewers: arsenm, tstellarAMD, mareko
Subscribers: arsenm, kzhuravl, llvm-commits
Differential Revision: https://reviews.llvm.org/D22675
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git-svn-id: https://llvm.org/svn/llvm-project/llvm/branches/release_39@277620 91177308-0d34-0410-b5e6-96231b3b80d8
Tom Stellard