Commit Graph

461 Commits

Author SHA1 Message Date
David Blaikie
2be3922807 Fix a couple of layering violations in Transforms
Remove #include of Transforms/Scalar.h from Transform/Utils to fix layering.

Transforms depends on Transforms/Utils, not the other way around. So
remove the header and the "createStripGCRelocatesPass" function
declaration (& definition) that is unused and motivated this dependency.

Move Transforms/Utils/Local.h into Analysis because it's used by
Analysis/MemoryBuiltins.cpp.

llvm-svn: 328165
2018-03-21 22:34:23 +00:00
Adrian Prantl
5b477be72a LowerDbgDeclare: ignore dbg.declares for allocas with volatile access
There is no point in lowering a dbg.declare describing an alloca that
has volatile loads or stores as users, since the alloca cannot be
elided. Lowering the dbg.declare will result in larger debug info that
may also have worse coverage than just describing the alloca.

rdar://problem/34496278

llvm-svn: 327092
2018-03-09 00:45:04 +00:00
Vedant Kumar
f69baf64eb [Utils] Salvage debug info in block simplification
In stage2 -O3 builds of llc, this results in small but measurable
increases in the number of variables with locations, and in the number
of unique source variables overall.

(According to llvm-dwarfdump --statistics, there are 123 additional
variables with locations, which is just a 0.006% improvement).

The size of the .debug_loc section of the llc dsym increases by 0.004%.

llvm-svn: 326629
2018-03-02 22:46:48 +00:00
Vedant Kumar
334fa57456 [Utils] Salvage debug info in recursive inst deletion
In stage2 -O3 builds of llc, this results in a 0.3% increase in the
number of variables with locations, and a 0.2% increase in the number of
unique source variables overall.

The size of the .debug_loc section of the llc dsym increases by 0.5%.

llvm-svn: 326621
2018-03-02 21:36:35 +00:00
Matt Davis
523c656e25 [Debug] Add dbg.value intrinsics for PHIs created during LCSSA.
Summary:
This patch is an enhancement to propagate dbg.value information when Phis are created on behalf of LCSSA.
I noticed a case where a value carried across a loop was reported as <optimized out>.

Specifically this case:
```
int bar(int x, int y) {
  return x + y;
}

int foo(int size) {
  int val = 0;
  for (int i = 0; i < size; ++i) {
    val = bar(val, i);  // Both val and i are correct
  }
  return val; // <optimized out>
}
```

In the above case, after all of the interesting computation completes our value
is reported as "optimized out." This change will add a dbg.value to correct this.

This patch also moves the dbg.value insertion routine from LoopRotation.cpp 
into Local.cpp, so that we can share it in both places (LoopRotation and LCSSA).

Reviewers: mzolotukhin, aprantl, vsk, davide

Reviewed By: aprantl, vsk

Subscribers: dberlin, llvm-commits

Differential Revision: https://reviews.llvm.org/D42551

llvm-svn: 325926
2018-02-23 17:38:27 +00:00
Vedant Kumar
1ceabcf080 [Utils] Avoid a hash table lookup in salvageDI, NFC
According to the current coverage report salvageDebugInfo() is called
5.12 million times during testing and almost always returns early.

The early return depends on LocalAsMetadata::getIfExists returning null,
which involves a DenseMap lookup in an LLVMContextImpl. We can probably
speed this up by simply checking the IsUsedByMD bit in Value.

llvm-svn: 325738
2018-02-22 01:29:41 +00:00
Vedant Kumar
044b588929 [Utils] salvageDI: Add a comment and move a call earlier, NFC
llvm-svn: 325280
2018-02-15 19:13:03 +00:00
Petar Jovanovic
1768957c82 [Utils] Salvage the debug info of DCE'ed 'and' instructions
Preserve debug info from a dead 'and' instruction with a constant.

Patch by Djordje Todorovic.

Differential Revision: https://reviews.llvm.org/D43163

llvm-svn: 325119
2018-02-14 13:10:35 +00:00
Elena Demikhovsky
945b7e5aa6 Adding a width of the GEP index to the Data Layout.
Making a width of GEP Index, which is used for address calculation, to be one of the pointer properties in the Data Layout.
p[address space]:size:memory_size:alignment:pref_alignment:index_size_in_bits.
The index size parameter is optional, if not specified, it is equal to the pointer size.

Till now, the InstCombiner normalized GEPs and extended the Index operand to the pointer width.
It works fine if you can convert pointer to integer for address calculation and all registered targets do this.
But some ISAs have very restricted instruction set for the pointer calculation. During discussions were desided to retrieve information for GEP index from the Data Layout.
http://lists.llvm.org/pipermail/llvm-dev/2018-January/120416.html

I added an interface to the Data Layout and I changed the InstCombiner and some other passes to take the Index width into account.
This change does not affect any in-tree target. I added tests to cover data layouts with explicitly specified index size.

Differential Revision: https://reviews.llvm.org/D42123

llvm-svn: 325102
2018-02-14 06:58:08 +00:00
Vedant Kumar
388fac5de6 [Utils] Salvage debug info from all no-op casts
We already try to salvage debug values from no-op bitcasts and inttoptr
instructions: we should handle ptrtoint instructions as well.

This saves an additional 24,444 debug values in a stage2 build of clang,
and (according to llvm-dwarfdump --statistics) provides an additional
289 unique source variables.

llvm-svn: 324982
2018-02-13 03:34:23 +00:00
Vedant Kumar
4011c26cc7 [Utils] Salvage debug info of DCE'ed mul/sdiv/srem instructions
Here are the number of additional debug values salvaged in a stage2
build of clang:

  63 SALVAGE: MUL
  1250 SALVAGE: SDIV

(No values were salvaged from `srem` instructions in this experiment,
but it's a simple case to handle so we might as well.)

llvm-svn: 324976
2018-02-13 01:09:52 +00:00
Vedant Kumar
31ec356a48 [Utils] Salvage debug info of DCE'ed shl/lhsr/ashr instructions
Here are the number of additional debug values salvaged in a stage2
build of clang:

  1912 SALVAGE: ASHR
   405 SALVAGE: LSHR
   249 SALVAGE: SHL

llvm-svn: 324975
2018-02-13 01:09:49 +00:00
Vedant Kumar
47b16c45d7 [Utils] Salvage the debug info of DCE'ed 'sub' instructions
This salvages 14 debug values in a stage2 build of clang.

llvm-svn: 324974
2018-02-13 01:09:47 +00:00
Vedant Kumar
96b7dc041b [Utils] Salvage the debug info of DCE'ed 'xor' instructions
This salvages 259 debug values in a stage2 build of clang.

Differential Revision: https://reviews.llvm.org/D43207

llvm-svn: 324973
2018-02-13 01:09:46 +00:00
Vedant Kumar
04386d8e3d [Utils] Salvage debug info from dead 'or' instructions
Extend salvageDebugInfo to preserve the debug info from a dead 'or'
with a constant.

Patch by Ismail Badawi!

Differential Revision: https://reviews.llvm.org/D43129

llvm-svn: 324764
2018-02-09 19:19:55 +00:00
Vedant Kumar
6394df9fc4 [Debug] LCSSA: Insert dbg.value at the first available insertion point
Inserting a dbg.value instruction at the start of a basic block with a
landingpad instruction triggers a verifier failure. We should be OK if
we insert the instruction a bit later.

Speculative fix for the bot failure described here:
https://reviews.llvm.org/D42551

llvm-svn: 323482
2018-01-25 23:48:29 +00:00
Vedant Kumar
6bfc869cf7 [Debug] Add a utility to propagate dbg.value to new PHIs, NFC
This simply moves an existing utility to Utils for reuse.

Split out of: https://reviews.llvm.org/D42551

Patch by Matt Davis!

llvm-svn: 323471
2018-01-25 21:37:05 +00:00
Brian M. Rzycki
9b7ae23256 [JumpThreading] Preservation of DT and LVI across the pass
Summary:
See D37528 for a previous (non-deferred) version of this
patch and its description.

Preserves dominance in a deferred manner using a new class
DeferredDominance. This reduces the performance impact of
updating the DominatorTree at every edge insertion and
deletion. A user may call DDT->flush() within JumpThreading
for an up-to-date DT. This patch currently has one flush()
at the end of runImpl() to ensure DT is preserved across
the pass.

LVI is also preserved to help subsequent passes such as
CorrelatedValuePropagation. LVI is simpler to maintain and
is done immediately (not deferred). The code to perform the
preversation was minimally altered and simply marked as
preserved for the PassManager to be informed.

This extends the analysis available to JumpThreading for
future enhancements such as threading across loop headers.

Reviewers: dberlin, kuhar, sebpop

Reviewed By: kuhar, sebpop

Subscribers: mgorny, dmgreen, kuba, rnk, rsmith, hiraditya, llvm-commits

Differential Revision: https://reviews.llvm.org/D40146

llvm-svn: 322401
2018-01-12 21:06:48 +00:00
Vedant Kumar
b2ec02ba0b [Utils] Simplify salvageDebugInfo, NFCI
Having a single call to findDbgUsers() allows salvageDebugInfo() to
return earlier.

Differential Revision: https://reviews.llvm.org/D41787

llvm-svn: 321915
2018-01-05 23:27:02 +00:00
Reid Kleckner
cd78ddc119 Revert "[JumpThreading] Preservation of DT and LVI across the pass"
This reverts r321825, it causes crashes in Chromium. Reproducer
forthcoming.

llvm-svn: 321832
2018-01-04 23:23:46 +00:00
Brian M. Rzycki
cdad6c0b60 [JumpThreading] Preservation of DT and LVI across the pass
Summary:
See D37528 for a previous (non-deferred) version of this
patch and its description.

Preserves dominance in a deferred manner using a new class
DeferredDominance. This reduces the performance impact of
updating the DominatorTree at every edge insertion and
deletion. A user may call DDT->flush() within JumpThreading
for an up-to-date DT. This patch currently has one flush()
at the end of runImpl() to ensure DT is preserved across
the pass.

LVI is also preserved to help subsequent passes such as
CorrelatedValuePropagation. LVI is simpler to maintain and
is done immediately (not deferred). The code to perfom the
preversation was minimally altered and was simply marked
as preserved for the PassManager to be informed.

This extends the analysis available to JumpThreading for
future enhancements. One example is loop boundary threading.

Reviewers: dberlin, kuhar, sebpop

Reviewed By: kuhar, sebpop

Subscribers: hiraditya, llvm-commits

Differential Revision: https://reviews.llvm.org/D40146

llvm-svn: 321825
2018-01-04 21:57:32 +00:00
Davide Italiano
0512bf5af2 [Utils/Local] Use auto when the type is obvious. NFCI.
llvm-svn: 321605
2017-12-31 16:51:50 +00:00
Davide Italiano
5dd1c587e7 [Utils] Remove commented debug message. NFCI.
llvm-svn: 321604
2017-12-31 16:48:44 +00:00
Sanjay Patel
c722e26549 fix typo in comment and remove inaccurate comment; NFC
llvm-svn: 320838
2017-12-15 18:25:13 +00:00
Brian M. Rzycki
580bc3c8fa Reverting [JumpThreading] Preservation of DT and LVI across the pass
Stage 2 bootstrap failed:
http://lab.llvm.org:8011/builders/clang-x86_64-linux-selfhost-modules-2/builds/14434

llvm-svn: 320641
2017-12-13 22:01:17 +00:00
Brian M. Rzycki
d989af98b3 [JumpThreading] Preservation of DT and LVI across the pass
Summary:
See D37528 for a previous (non-deferred) version of this
patch and its description.

Preserves dominance in a deferred manner using a new class
DeferredDominance. This reduces the performance impact of
updating the DominatorTree at every edge insertion and
deletion. A user may call DDT->flush() within JumpThreading
for an up-to-date DT. This patch currently has one flush()
at the end of runImpl() to ensure DT is preserved across
the pass.

LVI is also preserved to help subsequent passes such as
CorrelatedValuePropagation. LVI is simpler to maintain and
is done immediately (not deferred). The code to perfom the
preversation was minimally altered and was simply marked
as preserved for the PassManager to be informed.

This extends the analysis available to JumpThreading for
future enhancements. One example is loop boundary threading.

Reviewers: dberlin, kuhar, sebpop

Reviewed By: kuhar, sebpop

Subscribers: hiraditya, llvm-commits

Differential Revision: https://reviews.llvm.org/D40146

llvm-svn: 320612
2017-12-13 20:52:26 +00:00
Adrian Prantl
d13170174c Generalize llvm::replaceDbgDeclare and actually support the use-case that
is mentioned in the documentation (inserting a deref before the plus_uconst).

llvm-svn: 320203
2017-12-08 21:58:18 +00:00
Rafael Espindola
c06f55e1e8 This reverts commit r319096 and r319097.
Revert "[SROA] Propagate !range metadata when moving loads."
Revert "[Mem2Reg] Clang-format unformatted parts of this file. NFCI."

Davide says they broke a bot.

llvm-svn: 319131
2017-11-28 01:25:38 +00:00
Davide Italiano
b5d59e73ee [SROA] Propagate !range metadata when moving loads.
This tries to propagate !range metadata to a pre-existing load
when a load is optimized out. This is done instead of adding an
assume because converting loads to and from assumes creates a
lot of IR.

Patch by Ariel Ben-Yehuda.

Differential Revision:  https://reviews.llvm.org/D37216

llvm-svn: 319096
2017-11-27 21:25:13 +00:00
Reid Kleckner
29a5c03cc2 Make salvageDebugInfo of casts work for dbg.declare and dbg.addr
Summary:
Instcombine (and probably other passes) sometimes want to change the
type of an alloca. To do this, they generally create a new alloca with
the desired type, create a bitcast to make the new pointer type match
the old pointer type, replace all uses with the cast, and then simplify
the casts. We already knew how to salvage dbg.value instructions when
removing casts, but we can extend it to cover dbg.addr and dbg.declare.

Fixes a debug info quality issue uncovered in Chromium in
http://crbug.com/784609

Reviewers: aprantl, vsk

Subscribers: hiraditya, llvm-commits

Differential Revision: https://reviews.llvm.org/D40042

llvm-svn: 318203
2017-11-14 21:49:06 +00:00
Adrian Prantl
182f9fea37 InstCombine: salvage the debug info of DCE'ed add instructions.
rdar://problem/31209283

llvm-svn: 317522
2017-11-06 22:49:39 +00:00
Adrian Prantl
261ac8b23c Invoke salvageDebugInfo from CodeGenPrepare's SinkCast()
This preserves the debug info for the cast operation in the original location.

rdar://problem/33460652

Reapplied r317340 with the test moved into an ARM-specific directory.

llvm-svn: 317375
2017-11-03 21:55:03 +00:00
Adrian Prantl
8fe9fb0ae5 Revert "Invoke salvageDebugInfo from CodeGenPrepare's SinkCast()"
This reverts commit 317342 while investigating bot breakage.

llvm-svn: 317345
2017-11-03 18:26:36 +00:00
Adrian Prantl
58e9a0bb16 Invoke salvageDebugInfo from CodeGenPrepare's SinkCast()
This preserves the debug info for the cast operation in the original location.

rdar://problem/33460652

llvm-svn: 317340
2017-11-03 18:00:02 +00:00
Balaram Makam
9ee942f481 Reapply r316582 [Local] Fix a bug in the domtree update logic for MergeBasicBlockIntoOnlyPred.
Summary: This reverts r316612 to reapply r316582. The buildbot failure was unrelated to this commit.

Reviewers:

Subscribers:

llvm-svn: 316669
2017-10-26 15:04:53 +00:00
Balaram Makam
52252fe20d Revert r316582 [Local] Fix a bug in the domtree update logic for MergeBasicBlockIntoOnlyPred.
Summary: This reverts commit r316582. It looks like this commit broke tests on one buildbot:
http://lab.llvm.org:8011/builders/llvm-clang-x86_64-expensive-checks-win/builds/5719

. . .
Failing Tests (1):
    LLVM :: Transforms/CalledValuePropagation/simple-arguments.ll

Reviewers:

Subscribers:

llvm-svn: 316612
2017-10-25 21:32:54 +00:00
Balaram Makam
925ddf1a93 [Local] Fix a bug in the domtree update logic for MergeBasicBlockIntoOnlyPred.
Summary: For some irreducible CFG the domtree nodes might be dead, do not update domtree for dead nodes.

Reviewers: kuhar, dberlin, hfinkel

Reviewed By: kuhar

Subscribers: llvm-commits, mcrosier

Differential Revision: https://reviews.llvm.org/D38960

llvm-svn: 316582
2017-10-25 14:55:48 +00:00
Adrian Prantl
d20442d383 Delete unused instantiations of DIBuilder. NFC
llvm-svn: 316494
2017-10-24 20:26:17 +00:00
Eugene Zelenko
6cadde7f40 [Transforms] Fix some Clang-tidy modernize and Include What You Use warnings; other minor fixes (NFC).
llvm-svn: 316034
2017-10-17 21:27:42 +00:00
Daniel Jasper
0a51ec29c9 Revert r314435: "[JumpThreading] Preserve DT and LVI across the pass"
Causes a segfault on a builtbot (and in our internal bootstrapping of
Clang). See Eli's response on the commit thread.

llvm-svn: 314589
2017-09-30 11:57:19 +00:00
Evandro Menezes
3701df55c6 [JumpThreading] Preserve DT and LVI across the pass
JumpThreading now preserves dominance and lazy value information across the
entire pass.  The pass manager is also informed of this preservation with
the goal of DT and LVI being recalculated fewer times overall during
compilation.

This change prepares JumpThreading for enhanced opportunities; particularly
those across loop boundaries.

Patch by: Brian Rzycki <b.rzycki@samsung.com>,
          Sebastian Pop <s.pop@samsung.com>

Differential revision: https://reviews.llvm.org/D37528

llvm-svn: 314435
2017-09-28 17:24:40 +00:00
Reid Kleckner
0fe506bc5e Re-land r313825: "[IR] Add llvm.dbg.addr, a control-dependent version of llvm.dbg.declare"
The fix is to avoid invalidating our insertion point in
replaceDbgDeclare:
     Builder.insertDeclare(NewAddress, DIVar, DIExpr, Loc, InsertBefore);
+    if (DII == InsertBefore)
+      InsertBefore = &*std::next(InsertBefore->getIterator());
     DII->eraseFromParent();

I had to write a unit tests for this instead of a lit test because the
use list order matters in order to trigger the bug.

The reduced C test case for this was:
  void useit(int*);
  static inline void inlineme() {
    int x[2];
    useit(x);
  }
  void f() {
    inlineme();
    inlineme();
  }

llvm-svn: 313905
2017-09-21 19:52:03 +00:00
Daniel Jasper
7d2f38d600 Revert r313825: "[IR] Add llvm.dbg.addr, a control-dependent version of llvm.dbg.declare"
.. as well as the two subsequent changes r313826 and r313875.

This leads to segfaults in combination with ASAN. Will forward repro
instructions to the original author (rnk).

llvm-svn: 313876
2017-09-21 12:07:33 +00:00
Reid Kleckner
3f547e87b2 [IR] Add llvm.dbg.addr, a control-dependent version of llvm.dbg.declare
Summary:
This implements the design discussed on llvm-dev for better tracking of
variables that live in memory through optimizations:
  http://lists.llvm.org/pipermail/llvm-dev/2017-September/117222.html

This is tracked as PR34136

llvm.dbg.addr is intended to be produced and used in almost precisely
the same way as llvm.dbg.declare is today, with the exception that it is
control-dependent. That means that dbg.addr should always have a
position in the instruction stream, and it will allow passes that
optimize memory operations on local variables to insert llvm.dbg.value
calls to reflect deleted stores. See SourceLevelDebugging.rst for more
details.

The main drawback to generating DBG_VALUE machine instrs is that they
usually cause LLVM to emit a location list for DW_AT_location. The next
step will be to teach DwarfDebug.cpp how to recognize more DBG_VALUE
ranges as not needing a location list, and possibly start setting
DW_AT_start_offset for variables whose lifetimes begin mid-scope.

Reviewers: aprantl, dblaikie, probinson

Subscribers: eraman, hiraditya, llvm-commits

Differential Revision: https://reviews.llvm.org/D37768

llvm-svn: 313825
2017-09-20 21:52:33 +00:00
Adrian Prantl
abe04759a6 Remove the obsolete offset parameter from @llvm.dbg.value
There is no situation where this rarely-used argument cannot be
substituted with a DIExpression and removing it allows us to simplify
the DWARF backend. Note that this patch does not yet remove any of
the newly dead code.

rdar://problem/33580047
Differential Revision: https://reviews.llvm.org/D35951

llvm-svn: 309426
2017-07-28 20:21:02 +00:00
Daniel Neilson
2574d7cbf6 All libcalls should be considered to be GC-leaf functions.
Summary:
It is possible for some passes to materialize a call to a libcall (ex: ldexp, exp2, etc),
but these passes will not mark the call as a gc-leaf-function. All libcalls are
actually gc-leaf-functions, so we change llvm::callsGCLeafFunction() to tell us that
available libcalls are equivalent to gc-leaf-function calls.

Reviewers: sanjoy, anna, reames

Reviewed By: anna

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D35840

llvm-svn: 309291
2017-07-27 16:49:39 +00:00
Leo Li
93abd7d915 [ConstantHoisting] Remove dupliate logic in constant hoisting
Summary:
As metioned in https://reviews.llvm.org/D34576, checkings in
`collectConstantCandidates` can be replaced by using
`llvm::canReplaceOperandWithVariable`.

The only special case is that `collectConstantCandidates` return false for
all `IntrinsicInst` but it is safe for us to collect constant candidates from
`IntrinsicInst`.

Reviewers: pirama, efriedma, srhines

Reviewed By: efriedma

Subscribers: llvm-commits, javed.absar

Differential Revision: https://reviews.llvm.org/D34921

llvm-svn: 307587
2017-07-10 20:45:34 +00:00
Davide Italiano
4eb210bdeb [Local] Update the comment for removeUnreachableBlocks.
It referenced a wrong function name, and didn't mention what the
second argument did. This should be slightly more accurate now.

llvm-svn: 307425
2017-07-07 18:54:14 +00:00
Leo Li
5499b1b8be Modify constraints in llvm::canReplaceOperandWithVariable
Summary:
`Instruction::Switch`: only first operand can be set to a non-constant value.
`Instruction::InsertValue` both the first and the second operand can be set to a non-constant value.
`Instruction::Alloca` return true for non-static allocation.

Reviewers: efriedma

Reviewed By: efriedma

Subscribers: srhines, pirama, llvm-commits

Differential Revision: https://reviews.llvm.org/D34905

llvm-svn: 307294
2017-07-06 18:47:05 +00:00
Chandler Carruth
2abb65ae11 [InstCombine] Factor the logic for propagating !nonnull and !range
metadata out of InstCombine and into helpers.

NFC, this just exposes the logic used by InstCombine when propagating
metadata from one load instruction to another. The plan is to use this
in SROA to address PR32902.

If anyone has better ideas about how to factor this or name variables,
I'm all ears, but this seemed like a pretty good start and lets us make
progress on the PR.

This is based on a patch by Ariel Ben-Yehuda (D34285).

llvm-svn: 306267
2017-06-26 03:31:31 +00:00