Commit Graph

537 Commits

Author SHA1 Message Date
Bob Haarman
3749668cd8 Revert r360902 "Resubmit: [Salvage] Change salvage debug info ..."
This reverts commit rr360902. It caused an assertion failure in
lib/IR/DebugInfoMetadata.cpp: Assertion `(OffsetInBits + SizeInBits <=
FragmentSizeInBits) && "new fragment outside of original fragment"'
failed.

PR41931.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@361246 91177308-0d34-0410-b5e6-96231b3b80d8
2019-05-21 11:53:41 +00:00
Petar Jovanovic
0ddfb52ad6 [DebugInfoMetadata] Refactor DIExpression::prepend constants (NFC)
Refactor DIExpression::With* into a flag enum in order to be less
error-prone to use (as discussed on D60866).

Patch by Djordje Todorovic.

Differential Revision: https://reviews.llvm.org/D61943


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@361137 91177308-0d34-0410-b5e6-96231b3b80d8
2019-05-20 10:35:57 +00:00
Stephen Tozer
4ca34ad3d2 Resubmit: [Salvage] Change salvage debug info implementation to use DW_OP_LLVM_convert where needed
Fixes issue: https://bugs.llvm.org/show_bug.cgi?id=40645

Previously, LLVM had no functional way of performing casts inside of a
DIExpression(), which made salvaging cast instructions other than Noop casts
impossible. With the recent addition of DW_OP_LLVM_convert this salvaging is
now possible, and so can be used to fix the attached bug as well as any cases
where SExt instruction results are lost in the debugging metadata. This patch
introduces this fix by expanding the salvage debug info method to cover these
cases using the new operator.

Differential revision: https://reviews.llvm.org/D61184

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@360902 91177308-0d34-0410-b5e6-96231b3b80d8
2019-05-16 14:41:01 +00:00
Stephen Tozer
dabe45c6d5 Revert "[Salvage] Change salvage debug info implementation to use DW_OP_LLVM_convert where needed"
This reverts r360772 due to build issues.
Reverted commit: 17dd4d7403770bd683675e45f5517e0cdb8f9b2b.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@360773 91177308-0d34-0410-b5e6-96231b3b80d8
2019-05-15 13:41:44 +00:00
Stephen Tozer
76562e6377 [Salvage] Change salvage debug info implementation to use DW_OP_LLVM_convert where needed
Fixes issue: https://bugs.llvm.org/show_bug.cgi?id=40645

Previously, LLVM had no functional way of performing casts inside of a
DIExpression(), which made salvaging cast instructions other than Noop
casts impossible. With the recent addition of DW_OP_LLVM_convert this
salvaging is now possible, and so can be used to fix the attached bug as
well as any cases where SExt instruction results are lost in the
debugging metadata. This patch introduces this fix by expanding the
salvage debug info method to cover these cases using the new operator.

Differential revision: https://reviews.llvm.org/D61184

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@360772 91177308-0d34-0410-b5e6-96231b3b80d8
2019-05-15 13:15:48 +00:00
Jeremy Morse
cee924fc6a [DebugInfo] Use zero linenos for debug intrinsics when promoting dbg.declare
In certain circumstances, optimizations pick line numbers from debug
intrinsic instructions as the new location for altered instructions. This
is problematic because the line number of a debugging intrinsic is
meaningless (it doesn't produce any machine instruction), only the scope
information is valid. The result can be the line number of a variable
declaration "leaking" into real code from debugging intrinsics, making the
line table un-necessarily jumpy, and potentially different with / without
variable locations.

Fix this by using zero line numbers when promoting dbg.declare intrinsics
into dbg.values: this is safe for debug intrinsics as their line numbers
are meaningless, and reduces the scope for damage / misleading stepping
when optimizations pick locations from the wrong place.

Differential Revision: https://reviews.llvm.org/D59272


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@360415 91177308-0d34-0410-b5e6-96231b3b80d8
2019-05-10 10:03:41 +00:00
David Stuttard
f617e867ae [CodeGenPrepare] Limit recursion depth for collectBitParts
Summary:
Seeing some issues for windows debug pathological cases with collectBitParts
recursion (1525 levels of recursion!)
Setting the limit to 64 as this should be sufficient - passes all lit cases

Subscribers: llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D61728

Change-Id: I7f44cdc6c1badf1c2ccbf1b0c4b6afe27ecb39a1

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@360347 91177308-0d34-0410-b5e6-96231b3b80d8
2019-05-09 15:02:10 +00:00
Alina Sbirlea
c419d3f938 [MemorySSA] Teach LoopSimplify to preserve MemorySSA.
Summary:
Preserve MemorySSA in LoopSimplify, in the old pass manager, if the analysis is available.
Do not preserve it in the new pass manager.
Update tests.

Subscribers: nemanjai, jlebar, javed.absar, Prazek, kbarton, zzheng, jsji, llvm-commits, george.burgess.iv, chandlerc

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D60833

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@360270 91177308-0d34-0410-b5e6-96231b3b80d8
2019-05-08 17:05:36 +00:00
Wolfgang Pieb
04f5748397 [DEBUGINFO] Prevent Instcombine from dropping debuginfo when removing zexts
Zexts can be treated like no-op casts when it comes to assessing whether their
removal affects debug info.

Reviewer: aprantl

Differential Revision: https://reviews.llvm.org/D60641


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@358431 91177308-0d34-0410-b5e6-96231b3b80d8
2019-04-15 17:36:29 +00:00
Alexander Potapenko
04e1efbae2 [Transforms][ASan] Move findAllocaForValue() to Utils/Local.cpp. NFC
Summary:
Factor out findAllocaForValue() from ASan so that we can use it in
MSan to handle lifetime intrinsics.

Reviewers: eugenis, pcc

Subscribers: hiraditya, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D60615

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@358380 91177308-0d34-0410-b5e6-96231b3b80d8
2019-04-15 08:59:56 +00:00
Joseph Tremoulet
85027ee656 [SimplifyCFG] Don't split musttail call from ret
Summary:
When inserting an `unreachable` after a noreturn call, we must ensure
that it's not a musttail call to avoid breaking the IR invariants for
musttail calls.

Reviewers: fedor.sergeev, majnemer

Reviewed By: majnemer

Subscribers: hiraditya, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D60080

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@357485 91177308-0d34-0410-b5e6-96231b3b80d8
2019-04-02 15:48:58 +00:00
Brian Gesiak
b0d0b07731 [Transforms] Redundant getValueOperand (NFC)
`StoreInst::getValueOperand` is identical to `getOperand(0)`, so the call to
`getOperand(0)` can be replaced. Further, `SI->getValueOperand` is redundantly
called just a few lines down, despite its return value being stored in variable
`DV`. No functional change.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@357479 91177308-0d34-0410-b5e6-96231b3b80d8
2019-04-02 14:57:56 +00:00
Markus Lavin
6ce55cd841 [DebugInfo] Introduce DW_OP_LLVM_convert
Introduce a DW_OP_LLVM_convert Dwarf expression pseudo op that allows
for a convenient way to perform type conversions on the Dwarf expression
stack. As an additional bonus it paves the way for using other Dwarf
v5 ops that need to reference a base_type.

The new DW_OP_LLVM_convert is used from lib/Transforms/Utils/Local.cpp
to perform sext/zext on debug values but mainly the patch is about
preparing terrain for adding other Dwarf v5 ops that need to reference a
base_type.

For Dwarf v5 the op maps to DW_OP_convert and for earlier versions a
complex shift & mask pattern is generated to emulate sext/zext.

This is a recommit of r356442 with trivial fixes for the failing tests.

Differential Revision: https://reviews.llvm.org/D56587

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@356451 91177308-0d34-0410-b5e6-96231b3b80d8
2019-03-19 13:16:28 +00:00
Markus Lavin
58648f0890 Revert "[DebugInfo] Introduce DW_OP_LLVM_convert"
This reverts commit 1cf4b593a7.

Build bots found failing tests not detected locally.

Failing Tests (3):
  LLVM :: DebugInfo/Generic/convert-debugloc.ll
  LLVM :: DebugInfo/Generic/convert-inlined.ll
  LLVM :: DebugInfo/Generic/convert-linked.ll

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@356444 91177308-0d34-0410-b5e6-96231b3b80d8
2019-03-19 09:17:28 +00:00
Markus Lavin
1cf4b593a7 [DebugInfo] Introduce DW_OP_LLVM_convert
Introduce a DW_OP_LLVM_convert Dwarf expression pseudo op that allows
for a convenient way to perform type conversions on the Dwarf expression
stack. As an additional bonus it paves the way for using other Dwarf
v5 ops that need to reference a base_type.

The new DW_OP_LLVM_convert is used from lib/Transforms/Utils/Local.cpp
to perform sext/zext on debug values but mainly the patch is about
preparing terrain for adding other Dwarf v5 ops that need to reference a
base_type.

For Dwarf v5 the op maps to DW_OP_convert and for earlier versions a
complex shift & mask pattern is generated to emulate sext/zext.

Differential Revision: https://reviews.llvm.org/D56587

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@356442 91177308-0d34-0410-b5e6-96231b3b80d8
2019-03-19 08:48:19 +00:00
Chijun Sima
0ac04b4ce6 [DTU] Refine the interface and logic of applyUpdates
Summary:
This patch separates two semantics of `applyUpdates`:
1. User provides an accurate CFG diff and the dominator tree is updated according to the difference of `the number of edge insertions` and `the number of edge deletions` to infer the status of an edge before and after the update.
2. User provides a sequence of hints. Updates mentioned in this sequence might never happened and even duplicated.

Logic changes:

Previously, removing invalid updates is considered a side-effect of deduplication and is not guaranteed to be reliable. To handle the second semantic, `applyUpdates` does validity checking before deduplication, which can cause updates that have already been applied to be submitted again. Then, different calls to `applyUpdates` might cause unintended consequences, for example,
```
DTU(Lazy) and Edge A->B exists.
1. DTU.applyUpdates({{Delete, A, B}, {Insert, A, B}}) // User expects these 2 updates result in a no-op, but {Insert, A, B} is queued
2. Remove A->B
3. DTU.applyUpdates({{Delete, A, B}}) // DTU cancels this update with {Insert, A, B} mentioned above together (Unintended)
```
But by restricting the precondition that updates of an edge need to be strictly ordered as how CFG changes were made, we can infer the initial status of this edge to resolve this issue.

Interface changes:
The second semantic of `applyUpdates`  is separated to `applyUpdatesPermissive`.
These changes enable DTU(Lazy) to use the first semantic if needed, which is quite useful in `transforms/utils`.

Reviewers: kuhar, brzycki, dmgreen, grosser

Reviewed By: brzycki

Subscribers: hiraditya, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D58170

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@354669 91177308-0d34-0410-b5e6-96231b3b80d8
2019-02-22 13:48:38 +00:00
Chijun Sima
e9b2f29faf [DTU] Deprecate insertEdge*/deleteEdge*
Summary: This patch converts all existing `insertEdge*/deleteEdge*` to `applyUpdates` and marks `insertEdge*/deleteEdge*` as deprecated.

Reviewers: kuhar, brzycki

Reviewed By: kuhar, brzycki

Subscribers: hiraditya, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D58443

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@354652 91177308-0d34-0410-b5e6-96231b3b80d8
2019-02-22 05:41:43 +00:00
Jeremy Morse
814924db54 [DebugInfo] Don't salvage load operations (PR40628).
Salvaging a redundant load instruction into a debug expression hides a
memory read from optimisation passes. Passes that alter memory behaviour
(such as LICM promoting memory to a register) aren't aware of these debug
memory reads and leave them unaltered, making the debug variable location
point somewhere unsafe.

Teaching passes to know about these debug memory reads would be challenging
and probably incomplete. Finding dbg.value instructions that need to be fixed
would likely be computationally expensive too, as more analysis would be
required. It's better to not generate debug-memory-reads instead, alas.

Changed tests:
 * DeadStoreElim: test for salvaging of intermediate operations contributing
   to the dead store, instead of salvaging of the redundant load,
 * GVN: remove debuginfo behaviour checks completely, this behaviour is still
   covered by other tests,
 * InstCombine: don't test for salvaged loads, we're removing that behaviour.

Differential Revision: https://reviews.llvm.org/D57962


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@353824 91177308-0d34-0410-b5e6-96231b3b80d8
2019-02-12 10:54:30 +00:00
Chandler Carruth
7fe8f82f54 [CallSite removal] Migrate ConstantFolding APIs and implementation to
`CallBase`.

Users have been updated. You can see how to update any out-of-tree
usages: pass `cast<CallBase>(CS.getInstruction())`.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@353661 91177308-0d34-0410-b5e6-96231b3b80d8
2019-02-11 07:51:44 +00:00
Chandler Carruth
8677a19763 [CallSite removal] Migrate the statepoint GC infrastructure to use the
`CallBase` class rather than `CallSite` wrappers.

I pushed this change down through most of the statepoint infrastructure,
completely removing the use of CallSite where I could reasonably do so.
I ended up making a couple of cut-points: generic call handling
(instcombine, TLI, SDAG). As soon as it hit truly generic handling with
users outside the immediate code, I simply transitioned into or out of
a `CallSite` to make this a reasonable sized chunk.

Differential Revision: https://reviews.llvm.org/D56122

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@353660 91177308-0d34-0410-b5e6-96231b3b80d8
2019-02-11 07:42:30 +00:00
Fangrui Song
2f51464f16 [Local] Delete a redundant check. NFC
isInstructionTriviallyDead also performs the use_empty() check.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@353637 91177308-0d34-0410-b5e6-96231b3b80d8
2019-02-10 09:25:56 +00:00
Craig Topper
e3696113b6 Implementation of asm-goto support in LLVM
This patch accompanies the RFC posted here:
http://lists.llvm.org/pipermail/llvm-dev/2018-October/127239.html

This patch adds a new CallBr IR instruction to support asm-goto
inline assembly like gcc as used by the linux kernel. This
instruction is both a call instruction and a terminator
instruction with multiple successors. Only inline assembly
usage is supported today.

This also adds a new INLINEASM_BR opcode to SelectionDAG and
MachineIR to represent an INLINEASM block that is also
considered a terminator instruction.

There will likely be more bug fixes and optimizations to follow
this, but we felt it had reached a point where we would like to
switch to an incremental development model.

Patch by Craig Topper, Alexander Ivchenko, Mikhail Dvoretckii

Differential Revision: https://reviews.llvm.org/D53765

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@353563 91177308-0d34-0410-b5e6-96231b3b80d8
2019-02-08 20:48:56 +00:00
Carlos Alberto Enciso
2e390e6fde [DWARF] LLVM ERROR: Broken function found, while removing Debug Intrinsics.
Check that when SimplifyCFG is flattening a 'br', all their debug intrinsic instructions are removed, including any dbg.label referencing a label associated with the basic blocks being removed.

Differential Revision: https://reviews.llvm.org/D57444

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@353511 91177308-0d34-0410-b5e6-96231b3b80d8
2019-02-08 10:57:26 +00:00
Richard Trieu
1c34480b50 Move DomTreeUpdater from IR to Analysis
DomTreeUpdater depends on headers from Analysis, but is in IR.  This is a
layering violation since Analysis depends on IR.  Relocate this code from IR
to Analysis to fix the layering violation.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@353265 91177308-0d34-0410-b5e6-96231b3b80d8
2019-02-06 02:52:52 +00:00
Jeremy Morse
22ecef58b5 [DebugInfo][NFCI] Split salvageDebugInfo into helper functions
Some use cases are appearing where salvaging is needed that does not
correspond to an instruction being deleted -- for example an instruction
being sunk, or a Value not being available in a block being isel'd.

Enable more fine grained control over how salavging occurs by splitting
the logic into helper functions, separating things that are specific to
working on DbgVariableIntrinsics from those specific to interpreting IR
and building DIExpressions.

Differential Revision: https://reviews.llvm.org/D57696


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2019-02-05 11:11:28 +00:00
James Y Knight
e84538e816 [opaque pointer types] Pass function types to InvokeInst creation.
This cleans up all InvokeInst creation in LLVM to explicitly pass a
function type rather than deriving it from the pointer's element-type.

Differential Revision: https://reviews.llvm.org/D57171

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@352910 91177308-0d34-0410-b5e6-96231b3b80d8
2019-02-01 20:43:34 +00:00
James Y Knight
6029aa8149 [opaque pointer types] Pass function types to CallInst creation.
This cleans up all CallInst creation in LLVM to explicitly pass a
function type rather than deriving it from the pointer's element-type.

Differential Revision: https://reviews.llvm.org/D57170

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@352909 91177308-0d34-0410-b5e6-96231b3b80d8
2019-02-01 20:43:25 +00:00
Chandler Carruth
6b547686c5 Update the file headers across all of the LLVM projects in the monorepo
to reflect the new license.

We understand that people may be surprised that we're moving the header
entirely to discuss the new license. We checked this carefully with the
Foundation's lawyer and we believe this is the correct approach.

Essentially, all code in the project is now made available by the LLVM
project under our new license, so you will see that the license headers
include that license only. Some of our contributors have contributed
code under our old license, and accordingly, we have retained a copy of
our old license notice in the top-level files in each project and
repository.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@351636 91177308-0d34-0410-b5e6-96231b3b80d8
2019-01-19 08:50:56 +00:00
Vedant Kumar
eeb1971b1c [IR] Add Instruction::isLifetimeStartOrEnd, NFC
Instruction::isLifetimeStartOrEnd() checks whether an Instruction is an
llvm.lifetime.start or an llvm.lifetime.end intrinsic.

This was suggested as a cleanup in D55967.

Differential Revision: https://reviews.llvm.org/D56019

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@349964 91177308-0d34-0410-b5e6-96231b3b80d8
2018-12-21 21:49:40 +00:00
Michael Kruse
42a382c204 Introduce llvm.loop.parallel_accesses and llvm.access.group metadata.
The current llvm.mem.parallel_loop_access metadata has a problem in that
it uses LoopIDs. LoopID unfortunately is not loop identifier. It is
neither unique (there's even a regression test assigning the some LoopID
to multiple loops; can otherwise happen if passes such as LoopVersioning
make copies of entire loops) nor persistent (every time a property is
removed/added from a LoopID's MDNode, it will also receive a new LoopID;
this happens e.g. when calling Loop::setLoopAlreadyUnrolled()).
Since most loop transformation passes change the loop attributes (even
if it just to mark that a loop should not be processed again as
llvm.loop.isvectorized does, for the versioned and unversioned loop),
the parallel access information is lost for any subsequent pass.

This patch unlinks LoopIDs and parallel accesses.
llvm.mem.parallel_loop_access metadata on instruction is replaced by
llvm.access.group metadata. llvm.access.group points to a distinct
MDNode with no operands (avoiding the problem to ever need to add/remove
operands), called "access group". Alternatively, it can point to a list
of access groups. The LoopID then has an attribute
llvm.loop.parallel_accesses with all the access groups that are parallel
(no dependencies carries by this loop).

This intentionally avoid any kind of "ID". Loops that are clones/have
their attributes modifies retain the llvm.loop.parallel_accesses
attribute. Access instructions that a cloned point to the same access
group. It is not necessary for each access to have it's own "ID" MDNode,
but those memory access instructions with the same behavior can be
grouped together.

The behavior of llvm.mem.parallel_loop_access is not changed by this
patch, but should be considered deprecated.

Differential Revision: https://reviews.llvm.org/D52116

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@349725 91177308-0d34-0410-b5e6-96231b3b80d8
2018-12-20 04:58:07 +00:00
Vedant Kumar
726751627e [Util] Refer to [s|z]exts of args when converting dbg.declares (fix PR35400)
When converting dbg.declares, if the described value is a [s|z]ext,
refer to the ext directly instead of referring to its operand.

This fixes a narrowing bug (the debugger got the sign of a variable
wrong, see llvm.org/PR35400).

The main reason to refer to the ext's operand was that an optimization
may remove the ext itself, leading to a dropped variable. Now that
InstCombine has been taught to use replaceAllDbgUsesWith (r336451), this
is less of a concern. Other passes can/should adopt this API as needed
to fix dropped variable bugs.

Differential Revision: https://reviews.llvm.org/D51813

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@349214 91177308-0d34-0410-b5e6-96231b3b80d8
2018-12-15 00:03:33 +00:00
Michael Kruse
c681401eac [Transforms] Preserve metadata when converting invoke to call.
The `changeToCall` function did not preserve the invoke's metadata.
Currently, there is probably no metadata that depends on being applied
on a CallInst or InvokeInst. Therefore we can replace the instruction's
metadata.

This fixes http://llvm.org/PR39994

Suggested-by: Moritz Kreutzer <moritz.kreutzer@siemens.com>

Differential Revision: https://reviews.llvm.org/D55666

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@349170 91177308-0d34-0410-b5e6-96231b3b80d8
2018-12-14 18:15:11 +00:00
Davide Italiano
f4e1f61f71 [Local] Promote an utility that could be used elsewhere. NFCI.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@348804 91177308-0d34-0410-b5e6-96231b3b80d8
2018-12-10 22:17:04 +00:00
Vedant Kumar
94a229e81e [IR] Add hasNPredecessors, hasNPredecessorsOrMore to BasicBlock
Add methods to BasicBlock which make it easier to efficiently check
whether a block has N (or more) predecessors.

This can be more efficient than using pred_size(), which is a linear
time operation.

We might consider adding similar methods for successors. I haven't done
so in this patch because succ_size() is already O(1).

With this patch applied, I measured a 0.065% compile-time reduction in
user time for running `opt -O3` on the sqlite3 amalgamation (30 trials).
The change in mergeStoreIntoSuccessor alone saves 45 million linked list
iterations in a stage2 Release build of llc.

See llvm.org/PR39702 for a harder but more general way of achieving
similar results.

Differential Revision: https://reviews.llvm.org/D54686

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@347256 91177308-0d34-0410-b5e6-96231b3b80d8
2018-11-19 19:54:27 +00:00
Florian Hahn
196c060529 [Local] Keep K's range if K does not move when combining metadata.
As K has to dominate I, IIUC I's range metadata must be a subset of
K's. After Eli's recent clarification to the LangRef, loading a value
outside of the range is undefined behavior.
Therefore if I's range contains elements outside of K's range and we would load
one such value, K would cause undefined behavior.

In cases like hoisting/sinking, we still want the most generic range
over all code paths to/from the hoist/sink point. As suggested in the
patches related to D47339, I will refactor the handling of those
scenarios and try to decouple it from this function as follow up, once
we switched to a similar handling of metadata in most of
combineMetadata.

I updated some tests checking mostly the merging of metadata to keep the
metadata of to dominating load. The most interesting one is probably test8 in
test/Transforms/JumpThreading/thread-loads.ll. It contained a comment
about the alias metadata preventing us to eliminate the branch, but it
seem like the actual problem currently is that we merge the ranges of
both loads and cannot eliminate the icmp afterwards. With this patch, we
manage to eliminate the icmp, as the range of the first load excludes 8.

Reviewers: efriedma, nlopes, davide

Reviewed By: efriedma

Differential Revision: https://reviews.llvm.org/D51629


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@345456 91177308-0d34-0410-b5e6-96231b3b80d8
2018-10-27 16:53:45 +00:00
Carlos Alberto Enciso
406bb74d50 [DebugInfo][Dexter] Unreachable line stepped onto after SimplifyCFG.
When SimplifyCFG changes the PHI node into a select instruction, the debug line records becomes ambiguous. It causes the debugger to display unreachable source lines.

Differential Revision: https://reviews.llvm.org/D53287

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@345250 91177308-0d34-0410-b5e6-96231b3b80d8
2018-10-25 09:58:59 +00:00
Chandler Carruth
1744152581 [TI removal] Use Instruction instead of TerminatorInst for
a variable's type.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@344717 91177308-0d34-0410-b5e6-96231b3b80d8
2018-10-18 00:39:18 +00:00
Chandler Carruth
2aaf7228e0 [TI removal] Make variables declared as TerminatorInst and initialized
by `getTerminator()` calls instead be declared as `Instruction`.

This is the biggest remaining chunk of the usage of `getTerminator()`
that insists on the narrow type and so is an easy batch of updates.
Several files saw more extensive updates where this would cascade to
requiring API updates within the file to use `Instruction` instead of
`TerminatorInst`. All of these were trivial in nature (pervasively using
`Instruction` instead just worked).

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@344502 91177308-0d34-0410-b5e6-96231b3b80d8
2018-10-15 10:04:59 +00:00
Carlos Alberto Enciso
73cebd79c5 Revert "[DebugInfo][Dexter] Unreachable line stepped onto after SimplifyCFG."
This reverts commit r344120.

It was causing buildbot failures.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@344135 91177308-0d34-0410-b5e6-96231b3b80d8
2018-10-10 12:09:34 +00:00
Carlos Alberto Enciso
4ffb89c65a [DebugInfo][Dexter] Unreachable line stepped onto after SimplifyCFG.
When SimplifyCFG changes the PHI node into a select instruction, the debug line records becomes ambiguous. It causes the debugger to display unreachable source lines. 

Differential Revision: https://reviews.llvm.org/D52887

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@344120 91177308-0d34-0410-b5e6-96231b3b80d8
2018-10-10 08:29:55 +00:00
Carlos Alberto Enciso
e8654dabcf [DebugInfo][Dexter] Speculated BB presents illegal variable value to debugger.
When SimplifyCFG changes the PHI node into a select instruction, the debug information becomes ambiguous. It causes the debugger to display wrong variable value. 

Differential Revision: https://reviews.llvm.org/D51976

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@342527 91177308-0d34-0410-b5e6-96231b3b80d8
2018-09-19 08:16:56 +00:00
Chandler Carruth
9179aee2c1 [IR] Replace isa<TerminatorInst> with isTerminator().
This is a bit awkward in a handful of places where we didn't even have
an instruction and now we have to see if we can build one. But on the
whole, this seems like a win and at worst a reasonable cost for removing
`TerminatorInst`.

All of this is part of the removal of `TerminatorInst` from the
`Instruction` type hierarchy.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@340701 91177308-0d34-0410-b5e6-96231b3b80d8
2018-08-26 09:51:22 +00:00
Chandler Carruth
5eb83c58cd [IR] Begin removal of TerminatorInst by removing successor manipulation.
The core get and set routines move to the `Instruction` class. These
routines are only valid to call on instructions which are terminators.

The iterator and *generic* range based access move to `CFG.h` where all
the other generic successor and predecessor access lives. While moving
the iterator here, simplify it using the iterator utilities LLVM
provides and updates coding style as much as reasonable. The APIs remain
pointer-heavy when they could better use references, and retain the odd
behavior of `operator*` and `operator->` that is common in LLVM
iterators. Adjusting this API, if desired, should be a follow-up step.

Non-generic range iteration is added for the two instructions where
there is an especially easy mechanism and where there was code
attempting to use the range accessor from a specific subclass:
`indirectbr` and `br`. In both cases, the successors are contiguous
operands and can be easily iterated via the operand list.

This is the first major patch in removing the `TerminatorInst` type from
the IR's instruction type hierarchy. This change was discussed in an RFC
here and was pretty clearly positive:
http://lists.llvm.org/pipermail/llvm-dev/2018-May/123407.html

There will be a series of much more mechanical changes following this
one to complete this move.

Differential Revision: https://reviews.llvm.org/D47467

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@340698 91177308-0d34-0410-b5e6-96231b3b80d8
2018-08-26 08:41:15 +00:00
Florian Hahn
97d7bcd5c0 [Local] Make DoesKMove required for combineMetadata.
This patch makes the DoesKMove argument non-optional, to force people
to think about it. Most cases where it is false are either code hoisting
or code sinking, where we pick one instruction from a set of
equal instructions among different code paths.

Reviewers: dberlin, nlopes, efriedma, davide

Reviewed By: efriedma

Differential Revision: https://reviews.llvm.org/D47475


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@340606 91177308-0d34-0410-b5e6-96231b3b80d8
2018-08-24 11:40:04 +00:00
Alina Sbirlea
1f402bfa4f Update MemorySSA in Local utils removing blocks.
Summary: Extend Local utils to update MemorySSA.

Subscribers: sanjoy, jlebar, Prazek, george.burgess.iv, llvm-commits

Differential Revision: https://reviews.llvm.org/D48790

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@339951 91177308-0d34-0410-b5e6-96231b3b80d8
2018-08-16 21:58:44 +00:00
Anastasis Grammenos
a8ab9e6d20 [Local] Add dbg location on unreachable inst in changeToUnreachable
As show in https://bugs.llvm.org/show_bug.cgi?id=37960
it would be desirable to have debug location in the unreachable
instruction.

Also adds a unti test for this function.

Differential Revision: https://reviews.llvm.org/D50340

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2018-08-07 20:21:56 +00:00
Florian Hahn
512264ba6e [GVN,NewGVN] Keep nonnull if K does not move.
In combineMetadata, we should be able to preserve K's nonnull metadata,
if K does not move. This condition should hold for all replacements by
NewGVN/GVN, but I added a bunch of assertions to verify that.

Fixes PR35038.

There probably are additional kinds of metadata that could be preserved
using similar reasoning. This is follow-up work.

Reviewers: dberlin, davide, efriedma, nlopes

Reviewed By: efriedma

Differential Revision: https://reviews.llvm.org/D47339


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@339149 91177308-0d34-0410-b5e6-96231b3b80d8
2018-08-07 15:36:11 +00:00
Florian Hahn
926b53bb06 [GVN,NewGVN] Move patchReplacementInstruction to Utils/Local.h
This function is shared between both implementations. I am not sure if
Utils/Local.h is the best place though.

Reviewers: davide, dberlin, efriedma, xbolva00

Reviewed By: efriedma, xbolva00

Differential Revision: https://reviews.llvm.org/D47337


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@339138 91177308-0d34-0410-b5e6-96231b3b80d8
2018-08-07 13:27:33 +00:00
Hsiangkai Wang
cb6242dabb [DebugInfo] Refactor DbgInfoIntrinsic class hierarchy.
In the past, DbgInfoIntrinsic has a strong assumption that these
intrinsics all have variables and expressions attached to them.
However, it is too strong to derive the class for other debug entities.
Now, it has problems for debug labels.

In order to make DbgInfoIntrinsic as a base class for 'debug info', I
create a class for 'variable debug info', DbgVariableIntrinsic.

DbgDeclareInst, DbgAddrIntrinsic, and DbgValueInst will be derived from it.

Differential Revision: https://reviews.llvm.org/D50220

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@338984 91177308-0d34-0410-b5e6-96231b3b80d8
2018-08-06 03:59:47 +00:00
Chijun Sima
1a16c79be0 [Dominators] Make RemoveUnreachableBlocks return false if the BasicBlock is already awaiting deletion
Summary:
Previously, `removeUnreachableBlocks` still returns true (which indicates the CFG is changed) even when all the unreachable blocks found is awaiting deletion in the DDT class.
This makes code pattern like
```
// Code modified from lib/Transforms/Scalar/SimplifyCFGPass.cpp 
bool EverChanged = removeUnreachableBlocks(F, nullptr, DDT);
...
do {
    EverChanged = someMightHappenModifications();
    EverChanged |= removeUnreachableBlocks(F, nullptr, DDT);
  } while (EverChanged);
```
become a dead loop.
Fix this by detecting whether a BasicBlock is already awaiting deletion.

Reviewers: kuhar, brzycki, dmgreen, grosser, davide

Reviewed By: kuhar, brzycki

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D49738

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@338882 91177308-0d34-0410-b5e6-96231b3b80d8
2018-08-03 12:45:29 +00:00