Commit Graph

212 Commits

Author SHA1 Message Date
Reid Kleckner b518054b87 Rename AttributeSet to AttributeList
Summary:
This class is a list of AttributeSetNodes corresponding the function
prototype of a call or function declaration. This class used to be
called ParamAttrListPtr, then AttrListPtr, then AttributeSet. It is
typically accessed by parameter and return value index, so
"AttributeList" seems like a more intuitive name.

Rename AttributeSetImpl to AttributeListImpl to follow suit.

It's useful to rename this class so that we can rename AttributeSetNode
to AttributeSet later. AttributeSet is the set of attributes that apply
to a single function, argument, or return value.

Reviewers: sanjoy, javed.absar, chandlerc, pete

Reviewed By: pete

Subscribers: pete, jholewinski, arsenm, dschuff, mehdi_amini, jfb, nhaehnle, sbc100, void, llvm-commits

Differential Revision: https://reviews.llvm.org/D31102

llvm-svn: 298393
2017-03-21 16:57:19 +00:00
Sanjoy Das 8b859c26ec [JumpThreading] Re-enable JumpThreading for guards
Summary:
JumpThreading for guards feature has been reverted at https://reviews.llvm.org/rL295200
due to the following problem: the feature used the following algorithm for detection of
diamond patters:

1. Find a block with 2 predecessors;
2. Check that these blocks have a common single parent;
3. Check that the parent's terminator is a branch instruction.

The problem is that these checks are insufficient. They may pass for a non-diamond
construction in case if those two predecessors are actually the same block. This may
happen if parent's terminator is a br (either conditional or unconditional) to a block
that ends with "switch" instruction with exactly two branches going to one block.

This patch re-enables the JumpThreading for guards and fixes this issue by adding the
check that those found predecessors are actually different blocks. This guarantees that
parent's terminator is a conditional branch with exactly 2 different successors, which
is now ensured by assertions. It also adds two more tests for this situation (with parent's
terminator being a conditional and an unconditional branch).

Patch by Max Kazantsev!

Reviewers: anna, sanjoy, reames

Reviewed By: sanjoy

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D30036

llvm-svn: 295410
2017-02-17 04:21:14 +00:00
Anna Thomas 94c8d4976c Revert "[JumpThreading] Thread through guards"
This reverts commit r294617.

We fail on an assert while trying to get a condition from an
unconditional branch.

llvm-svn: 295200
2017-02-15 17:08:29 +00:00
Sanjoy Das 74bda4d591 [JumpThreading] Thread through guards
Summary:
This patch allows JumpThreading also thread through guards.
Virtually, guard(cond) is equivalent to the following construction:

  if (cond) { do something } else {deoptimize}

Yet it is not explicitly converted into IFs before lowering.
This patch enables early threading through guards in simple cases.
Currently it covers the following situation:

  if (cond1) {
    // code A
  } else {
    // code B
  }
  // code C
  guard(cond2)
  // code D

If there is implication cond1 => cond2 or !cond1 => cond2, we can transform
this construction into the following:

  if (cond1) {
    // code A
    // code C
  } else {
    // code B
    // code C
    guard(cond2)
  }
  // code D

Thus, removing the guard from one of execution branches.

Patch by Max Kazantsev!

Reviewers: reames, apilipenko, igor-laevsky, anna, sanjoy

Reviewed By: sanjoy

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D29620

llvm-svn: 294617
2017-02-09 19:40:22 +00:00
David Majnemer 5554edabef [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.

llvm-svn: 279268
2016-08-19 16:37:40 +00:00
David Majnemer 4eefd6bca4 Forgot the dyn_cast_or_null intended for r277691.
llvm-svn: 277693
2016-08-04 04:47:18 +00:00
David Majnemer 909793fa63 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.

llvm-svn: 277691
2016-08-04 04:24:02 +00:00
Reid Kleckner a6be60871f Revert "[CloneFunction] Don't remove side effecting calls"
This reverts commit r277611 and the followup r277614.

Bootstrap builds and chromium builds are crashing during inlining after
this change.

llvm-svn: 277642
2016-08-03 20:01:01 +00:00
David Majnemer fa8ef91748 [CloneFunction] Don't crash if the value map doesn't hold something
It is possible for the value map to not have an entry for some value
that has already been removed.

I don't have a testcase, this is fall-out from a buildbot.

llvm-svn: 277614
2016-08-03 17:37:10 +00:00
David Majnemer fad0490869 [CloneFunction] Don't remove side effecting calls
We were able to figure out that the result of a call is some constant.
While propagating that fact, we added the constant to the value map.
This is problematic because it results in us losing the call site when
processing the value map.

This fixes PR28802.

llvm-svn: 277611
2016-08-03 17:12:47 +00:00
Benjamin Kramer 135f735af1 Apply clang-tidy's modernize-loop-convert to most of lib/Transforms.
Only minor manual fixes. No functionality change intended.

llvm-svn: 273808
2016-06-26 12:28:59 +00:00
David Majnemer b8da3a2bb2 Reinstate r273711
r273711 was reverted by r273743.  The inliner needs to know about any
call sites in the inlined function.  These were obscured if we replaced
a call to undef with an undef but kept the call around.

This fixes PR28298.

llvm-svn: 273753
2016-06-25 00:04:10 +00:00
Nico Weber ae2ef4ccd4 Revert r273711, it caused PR28298.
llvm-svn: 273743
2016-06-24 22:52:39 +00:00
David Majnemer 3b3e954ea2 SimplifyInstruction does not imply DCE
We cannot remove an instruction with no uses just because
SimplifyInstruction succeeds.  It may have side effects.

llvm-svn: 273711
2016-06-24 19:34:46 +00:00
Vikram TV c702b8b3d7 Delay dominator updation while cloning loop.
Summary:
Dominator updation fails for a loop inserted with a new basicblock.

A block required by DT to set the IDom might not have been cloned yet. This is because there is no predefined ordering of loop blocks (except for the header block which should be the first block in the list).

The patch first creates DT nodes for the cloned blocks and then separately updates the DT in a follow-on loop.

Reviewers: anemet, dberlin

Subscribers: dberlin, llvm-commits

Differential Revision: http://reviews.llvm.org/D20899

llvm-svn: 272479
2016-06-11 16:41:10 +00:00
Peter Collingbourne 382d81cacf IR: Allow multiple global metadata attachments with the same type.
This will be necessary to allow the global merge pass to attach
multiple debug info metadata nodes to global variables once we reverse
the edge from DIGlobalVariable to GlobalVariable.

Differential Revision: http://reviews.llvm.org/D20414

llvm-svn: 271358
2016-06-01 01:17:57 +00:00
Peter Collingbourne dba995601b Cloning: Clean up the interface to the CloneFunction function.
Remove the ModuleLevelChanges argument, and the ability to create new
subprograms for cloned functions. The latter was added without review in
r203662, but it has no in-tree clients (all non-test callers pass false
for ModuleLevelChanges [1], so it isn't reachable outside of tests). It
also isn't clear that adding a duplicate subprogram to the compile unit is
always the right thing to do when cloning a function within a module. If
this functionality comes back it should be accompanied with a more concrete
use case.

Furthermore, all in-tree clients add the returned function to the module.
Since that's pretty much the only sensible thing you can do with the function,
just do that in CloneFunction.

[1] http://llvm-cs.pcc.me.uk/lib/Transforms/Utils/CloneFunction.cpp/rCloneFunction

Differential Revision: http://reviews.llvm.org/D18628

llvm-svn: 269110
2016-05-10 20:23:24 +00:00
Vaivaswatha Nagaraj 08efb0efcd [Cloning] cloneLoopWithPreheader(): add assert to ensure no sub-loops
Summary:
cloneLoopWithPreheader() does not update LoopInfo for sub-loop of
the original loop being cloned. Add assert to ensure no sub-loops for loop being cloned.

Reviewers: anemet, ashutosh.nema, hfinkel

Subscribers: mzolotukhin, llvm-commits

Differential Revision: http://reviews.llvm.org/D15922

llvm-svn: 267671
2016-04-27 05:25:09 +00:00
Duncan P. N. Exon Smith 724c503499 Transforms: Try harder to fix bootstrap after r266565
This catches two nullptr insertions into the ValueMap I missed in
r266567.  I missed CloneFunction becuase it never calls RemapInstruction
directly.  Here's one of the still-failing bots:
  http://lab.llvm.org:8011/builders/clang-x64-ninja-win7/builds/11496

llvm-svn: 266570
2016-04-17 20:11:09 +00:00
Duncan P. N. Exon Smith 3d555ac96d ValueMapper: Don't allow explicit null mappings of Values, NFC
As a follow-up to r123058, assert that there are no null mappings in the
ValueMap instead of just ignoring them when they are there.  There were
a couple of accidental insertions in CloneFunction so I cleaned those up
(caught by testcases).

llvm-svn: 266565
2016-04-17 18:53:24 +00:00
Adrian Prantl 75819aedf6 [PR27284] Reverse the ownership between DICompileUnit and DISubprogram.
Currently each Function points to a DISubprogram and DISubprogram has a
scope field. For member functions the scope is a DICompositeType. DIScopes
point to the DICompileUnit to facilitate type uniquing.

Distinct DISubprograms (with isDefinition: true) are not part of the type
hierarchy and cannot be uniqued. This change removes the subprograms
list from DICompileUnit and instead adds a pointer to the owning compile
unit to distinct DISubprograms. This would make it easy for ThinLTO to
strip unneeded DISubprograms and their transitively referenced debug info.

Motivation
----------

Materializing DISubprograms is currently the most expensive operation when
doing a ThinLTO build of clang.

We want the DISubprogram to be stored in a separate Bitcode block (or the
same block as the function body) so we can avoid having to expensively
deserialize all DISubprograms together with the global metadata. If a
function has been inlined into another subprogram we need to store a
reference the block containing the inlined subprogram.

Attached to https://llvm.org/bugs/show_bug.cgi?id=27284 is a python script
that updates LLVM IR testcases to the new format.

http://reviews.llvm.org/D19034
<rdar://problem/25256815>

llvm-svn: 266446
2016-04-15 15:57:41 +00:00
Duncan P. N. Exon Smith da68cbc4ad IR: RF_IgnoreMissingValues => RF_IgnoreMissingLocals, NFC
Clarify what this RemapFlag actually means.

  - Change the flag name to match its intended behaviour.
  - Clearly document that it's not supposed to affect globals.
  - Add a host of FIXMEs to indicate how to fix the behaviour to match
    the intent of the flag.

RF_IgnoreMissingLocals should only affect the behaviour of
RemapInstruction for function-local operands; namely, for operands of
type Argument, Instruction, and BasicBlock.  Currently, it is *only*
passed into RemapInstruction calls (and the transitive MapValue calls
that it makes).

When I split Metadata from Value I didn't understand the flag, and I
used it in a bunch of places for "global" metadata.

This commit doesn't have any functionality change, but prepares to
cleanup MapMetadata and MapValue.

llvm-svn: 265628
2016-04-07 00:26:43 +00:00
Peter Collingbourne 2bc252acd5 Cloning: Reduce complexity of debug info cloning and fix correctness issue.
Commit r260791 contained an error in that it would introduce a cross-module
reference in the old module. It also introduced O(N^2) complexity in the
module cloner by requiring the entire module to be visited for each function.
Fix both of these problems by avoiding use of the CloneDebugInfoMetadata
function (which is only designed to do intra-module cloning) and cloning
function-attached metadata in the same way that we clone all other metadata.

Differential Revision: http://reviews.llvm.org/D18583

llvm-svn: 264935
2016-03-30 22:05:13 +00:00
Easwaran Raman b1bd398ceb Revert revisions 262636, 262643, 262679, and 262682.
llvm-svn: 262883
2016-03-08 00:36:35 +00:00
Easwaran Raman 3035719c86 Infrastructure for PGO enhancements in inliner
This patch provides the following infrastructure for PGO enhancements in inliner:

Enable the use of block level profile information in inliner
Incremental update of block frequency information during inlining
Update the function entry counts of callees when they get inlined into callers.

Differential Revision: http://reviews.llvm.org/D16381

llvm-svn: 262636
2016-03-03 18:26:33 +00:00