Commit Graph

4485 Commits

Author SHA1 Message Date
Arthur Eubanks e5766f25c6 Use uint64_t for branch weights instead of uint32_t
CallInst::updateProfWeight() creates branch_weights with i64 instead of i32.
To be more consistent everywhere and remove lots of casts from uint64_t
to uint32_t, use i64 for branch_weights.

Reviewed By: davidxl

Differential Revision: https://reviews.llvm.org/D88609
2020-10-26 20:24:04 -07:00
Duncan P. N. Exon Smith ebb4ea1d53 IR: Simplify two loops walking ConstantDataSequential, NFC
Follow-up to b2b7cf39d5.

Differential Revision: https://reviews.llvm.org/D90198
2020-10-26 21:55:48 -04:00
Duncan P. N. Exon Smith 52821f6a71 IR: Add a comment at missing std::make_unique calls from b2b7cf39d5, NFC 2020-10-26 21:18:34 -04:00
Adrian Prantl 5b3bf8b453 [DebugInfo] Expose Fortran array debug info attributes through DIBuilder.
The support of a few debug info attributes specifically for Fortran
arrays have been added to LLVM recently, but there's no way to take
advantage of them through DIBuilder. This patch extends
DIBuilder::createArrayType to enable the settings of those attributes.

Patch by Chih-Ping Chen!

Differential Revision: https://reviews.llvm.org/D89817
2020-10-26 16:23:36 -07:00
Duncan P. N. Exon Smith b2b7cf39d5 IR: Clarify ownership of ConstantDataSequentials, NFC
Change `ConstantDataSequential::Next` to a
`unique_ptr<ConstantDataSequential>` and update `CDSConstants` to a
`StringMap<unique_ptr<ConstantDataSequential>>`, making the ownership
more obvious.

Differential Revision: https://reviews.llvm.org/D90083
2020-10-26 18:47:25 -04:00
Duncan P. N. Exon Smith d4c667c9af Avoid unnecessary uses of `MDNode::getTemporary`, NFC
This is a long-delayed follow-up to
5e5b85098d.

`TempMDNode` includes a bunch of machinery for RAUW, and should only be
used when necessary. RAUW wasn't being used in any of these cases... it
was just a placeholder for a self-reference.

Where the real node was using `MDNode::getDistinct`, just replace the
temporary argument with `nullptr`.

Where the real node was using `MDNode::get`, the `replaceOperandWith`
call was "promoting" the node to a distinct one implicitly due to
self-reference detection in `MDNode::handleChangedOperand`. The
`TempMDNode` was serving a purpose by delaying uniquing, but it's way
simpler to just call `MDNode::getDistinct` in the first place.

Note that using a self-reference at all in these places is a hold-over
from before `distinct` metadata existed. It was an old trick to create
distinct nodes. It would be intrusive to change, including bitcode
upgrades, etc., and it's harmless so I'm not sure there's much value in
removing it from existing schemas. After this commit it still has a tiny
memory cost (in the extra metadata operand) but no more overhead in
construction.

Differential Revision: https://reviews.llvm.org/D90079
2020-10-26 17:03:25 -04:00
Nick Desaulniers b7926ce6d7 [IR] add fn attr for no_stack_protector; prevent inlining on mismatch
It's currently ambiguous in IR whether the source language explicitly
did not want a stack a stack protector (in C, via function attribute
no_stack_protector) or doesn't care for any given function.

It's common for code that manipulates the stack via inline assembly or
that has to set up its own stack canary (such as the Linux kernel) would
like to avoid stack protectors in certain functions. In this case, we've
been bitten by numerous bugs where a callee with a stack protector is
inlined into an __attribute__((__no_stack_protector__)) caller, which
generally breaks the caller's assumptions about not having a stack
protector. LTO exacerbates the issue.

While developers can avoid this by putting all no_stack_protector
functions in one translation unit together and compiling those with
-fno-stack-protector, it's generally not very ergonomic or as
ergonomic as a function attribute, and still doesn't work for LTO. See also:
https://lore.kernel.org/linux-pm/20200915172658.1432732-1-rkir@google.com/
https://lore.kernel.org/lkml/20200918201436.2932360-30-samitolvanen@google.com/T/#u

Typically, when inlining a callee into a caller, the caller will be
upgraded in its level of stack protection (see adjustCallerSSPLevel()).
By adding an explicit attribute in the IR when the function attribute is
used in the source language, we can now identify such cases and prevent
inlining.  Block inlining when the callee and caller differ in the case that one
contains `nossp` when the other has `ssp`, `sspstrong`, or `sspreq`.

Fixes pr/47479.

Reviewed By: void

Differential Revision: https://reviews.llvm.org/D87956
2020-10-23 11:55:39 -07:00
Serge Pavlov 7975b8c38d [IR] Merge metadata manipulation code into Value
Now there are two main classes in Value hierarchy, which support metadata,
these are Instruction and GlobalObject. They implement different APIs for
metadata manipulation, which however overlap. This change moves metadata
manipulation code into Value, so descendant classes can use this code for
their operations on metadata.

No functional changes intended.

Differential Revision: https://reviews.llvm.org/D67626
2020-10-23 11:08:26 +07:00
Nikita Popov c0e8c94373 [DomTree] Make assert more precise
Per asbirlea's comment, assert that only instructions, constants
and arguments are passed to this API. Simplify returning true
would not be correct for special Value subclasses like MemoryAccess.
2020-10-22 22:40:06 +02:00
Nikita Popov 32b6e9a450 [DomTree] Accept Value as Def (NFC)
Non-instruction defs like arguments, constants or global values
always dominate all instructions/uses inside the function. This
case currently needs to be treated separately by the caller, see
https://reviews.llvm.org/D89623#inline-832818 for an example.

This patch makes the dominator tree APIs accept a Value instead of
an Instruction and always returns true for the non-Instruction case.

A complication here is that BasicBlocks are also Values. For that
reason we can't support the dominates(Value *, BasicBlock *)
variant, as it would conflict with dominates(BasicBlock *, BasicBlock *),
which has different semantics. For the other two APIs we assert
that the passed value is not a BasicBlock.

Differential Revision: https://reviews.llvm.org/D89632
2020-10-22 18:32:03 +02:00
Artur Pilipenko e8cce5ad89 [RS4GC] NFC. Preparatory refactoring to make GC parseable memcpy
For GC parseable element atomic memcpy/memmove we'll need to
shuffle statepoint arguments. Make it possible by storing the
arguments as Value *, not Use *.
2020-10-21 12:38:20 -07:00
Kazu Hirata 96f372c1e7 [AsmWriter] Construct SlotTracker with the function
This patch teaches BasicBlock::print to construct an instance of
SlotTracker with the containing function.

Without this patch, we dump:

*** IR Dump After LoopInstSimplifyPass ***
; Preheader:
  br label %1

; Loop:
<badref>:                                         ; preds = %1, %0
  br label %1

Note "<badref>" above.  This happens because BasicBlock::print calls:

  SlotTracker SlotTable(this->getModule());

Note that this constructor does not add the contents of functions to
the slot table.  That is, basic blocks are left unnumbered.

This patch fixes the problem by switching to:

  SlotTracker SlotTable(this->getParent());

which does add the contents of the Module and the function,
this->getParent(), to the slot table.

Differential Revision: https://reviews.llvm.org/D89567
2020-10-20 15:01:40 -07:00
Shimin Cui 95bda510fb [ConstantFold] Fold the comparison of bitcasted global values
This is to simplify icmp instructions in the form like:

%cmp = icmp eq i32 (i8*, i8*)* bitcast (i32 (i32**, i32**)* @f32 to i32
%(i8*, i8*)), bitcast (i32 (i64**, i64**) @f64 to i32 (i8*, i8*)*)

Here @f32 and @f64 are two functions.

Differential Revision: https://reviews.llvm.org/D87850
2020-10-20 12:41:49 -07:00
David Stenberg 0c0fcea557 Handle value uses wrapped in metadata for the use-list order
When generating the use-list order, also consider value uses that are
operands which are wrapped in metadata; e.g. llvm.dbg.value operands.

This fixes PR36778. The test case is based on the reproducer from that
report.

Reviewed By: dexonsmith

Differential Revision: https://reviews.llvm.org/D53758
2020-10-20 20:05:59 +02:00
Nicolai Hähnle c0cdd22c72 Introduce CfgTraits abstraction
The CfgTraits abstraction simplfies writing algorithms that are
generic over the type of CFG, and enables writing such algorithms
as regular non-template code that operates on opaque references
to CFG blocks and values.

Implementations of CfgTraits provide operations on the concrete
CFG types, e.g. `IrCfgTraits::BlockRef` is `BasicBlock *`.

CfgInterface is an abstract base class which provides operations
on opaque types CfgBlockRef and CfgValueRef. Those opaque types
encapsulate a `void *`, but the meaning depends on the concrete
CFG type. For example, MachineCfgTraits -- for use with MachineIR
in SSA form -- encodes a Register inside CfgValueRef. Converting
between concrete references and opaque/generic ones is done by
CfgTraits::{fromGeneric,toGeneric}. Convenience methods
CfgTraits::{un}wrap{Iterator,Range} are available as well.

Writing algorithms in terms of CfgInterface adds some overhead
(virtual method calls, plus in same cases it removes the
opportunity to inline iterators), but can be much more convenient
since generic algorithms can be written as non-templates.

This patch adds implementations of CfgTraits for all CFGs on
which dominator trees are calculated, so that the dominator
tree can be ported to this machinery. Only IrCfgTraits (LLVM IR)
and MachineCfgTraits (Machine IR in SSA form) are complete, the
other implementations are limited to the absolute minimum
required to make the upcoming dominator tree changes work.

v5:
- fix MachineCfgTraits::blockdef_iterator and allow it to iterate over
  the instructions in a bundle
- use MachineBasicBlock::printName

v6:
- implement predecessors/successors for all CfgTraits implementations
- fix error in unwrapRange
- rename toGeneric/fromGeneric into wrapRef/unwrapRef to have naming
  that is consistent with {wrap,unwrap}{Iterator,Range}
- use getVRegDef instead of getUniqueVRegDef

v7:
- std::forward fix in wrapping_iterator
- fix typos

v8:
- cleanup operators on CfgOpaqueType
- address other review comments

Change-Id: Ia75f4f268fded33fca11218a7d578c9aec1f3f4d

Differential Revision: https://reviews.llvm.org/D83088
2020-10-20 13:50:52 +02:00
Atmn Patel 595c615606 [IR] Adds mustprogress as a LLVM IR attribute
This adds the LLVM IR attribute `mustprogress` as defined in LangRef through D86233. This attribute will be applied to functions with in languages like C++ where forward progress is guaranteed. Functions without this attribute are not required to make progress.

Reviewed By: nikic

Differential Revision: https://reviews.llvm.org/D85393
2020-10-20 03:09:57 -04:00
Alok Kumar Sharma 0538353b3b [DebugInfo] Support for DWARF operator DW_OP_over
LLVM rejects DWARF operator DW_OP_over. This DWARF operator is needed
for Flang to support assumed rank array.

  Summary:
Currently LLVM rejects DWARF operator DW_OP_over. Below error is
produced when llvm finds this operator.
[..]
invalid expression
!DIExpression(151, 20, 16, 48, 30, 35, 80, 34, 6)
warning: ignoring invalid debug info in over.ll
[..]
There were some parts missing in support of this operator, which are
now completed.

  Testing
-added a unit testcase
-check-debuginfo
-check-llvm

Reviewed By: aprantl

Differential Revision: https://reviews.llvm.org/D89208
2020-10-17 08:42:28 +05:30
Matt Arsenault 0a7cd99a70 Reapply "OpaquePtr: Add type to sret attribute"
This reverts commit eb9f7c28e5.

Previously this was incorrectly handling linking of the contained
type, so this merges the fixes from D88973.
2020-10-16 11:05:02 -04:00
Jameson Nash 122d92dfc3 fix symbol printing on windows
Similar to MCSymbol::print in 3d6c8ebb58
(llvm-svn: 81682, PR4966), these symbols may need to be quoted to be handled by
the linker correctly.

Reviewed By: compnerd

Differential Revision: https://reviews.llvm.org/D87099
2020-10-15 17:14:55 -04:00
Matt Arsenault 6da31fa4a6 InstCombine: Fix infinite loop in copy-constant-to-alloca transform
This was broken by 16295d521e, when
instructions started being handled and not just constant
expressions. This was re-inserting an equivalent bitcast to the
original memcpy operand, which made a non-functional IR change on
every iteration.

This also fixes a secondary problem where it was inserting
addrspacecasts which may not have been legal (i.e. it changed the
source address space). Start visiting all pointer users and fail out
if we can't process them. Also start handling the relevant memory
intrinsic users. These cases can be dealt with by running
InferAddressSpaces separately.
2020-10-14 12:55:25 -04:00
Ahsan Saghir f3202b30b8 [PowerPC] Add assemble disassemble intrinsics for MMA
This patch adds support for assemble disassemble intrinsics
for MMA.

Reviewed By: bsaleil, #powerpc

Differential Revision: https://reviews.llvm.org/D88739
2020-10-13 13:21:58 -05:00
Simon Pilgrim 9c3138bd6d [InstCombine] visitTrunc - pass through undefs for trunc(shift(trunc/ext(x),c)) patterns
Based on the recent patches D88475 and D88429 where we are losing undef values due to extension/comparisons.

I've added a Constant::mergeUndefsWith method that merges the undef scalar/elements from another Constant into a specific Constant.

Differential Revision: https://reviews.llvm.org/D88687
2020-10-13 14:35:18 +01:00
Simon Pilgrim b752daa26b [InstCombine] Replace getLogBase2 internal helper with ConstantExpr::getExactLogBase2. NFCI.
This exposes the helper for other power-of-2 instcombine folds that I'm intending to add vector support to.

The helper only operated on power-of-2 constants so getExactLogBase2 is a more accurate name.
2020-10-11 10:31:17 +01:00
Alok Kumar Sharma 96bd4d34a2 [DebugInfo] Support for DWARF attribute DW_AT_rank
This patch adds support for DWARF attribute DW_AT_rank.

  Summary:
Fortran assumed rank arrays have dynamic rank. DWARF attribute
DW_AT_rank is needed to support that.

  Testing:
unit test cases added (hand-written)
check llvm
check debug-info

Reviewed By: aprantl

Differential Revision: https://reviews.llvm.org/D89141
2020-10-10 17:51:12 +05:30
Bevin Hansson 14a217534b [IR] Add Type::getFloatingPointTy.
It is possible to get a fltSemantics of a particular Type,
but there is no way to produce a Type based on a
fltSemantics.

This adds the function Type::getFloatingPointTy, which
will return the appropriate floating point Type for a given
fltSemantics.

ConstantFP is modified to use this function instead of
implementing it itself. Also some minor refactors to use
Type::getFltSemantics instead of a hand-rolled version.

Differential Revision: https://reviews.llvm.org/D87512
2020-10-09 10:27:41 +02:00
Philip Reames ef8b4e4fcd Add validity assert on entry to CastInst::isNoopCast [NFC]
This required some minor code reorganization to have a version of castIsValid which worked purely in terms of types.
2020-10-07 14:05:45 -07:00
Amara Emerson 322d0afd87 [llvm][mlir] Promote the experimental reduction intrinsics to be first class intrinsics.
This change renames the intrinsics to not have "experimental" in the name.

The autoupgrader will handle legacy intrinsics.

Relevant ML thread: http://lists.llvm.org/pipermail/llvm-dev/2020-April/140729.html

Differential Revision: https://reviews.llvm.org/D88787
2020-10-07 10:36:44 -07:00
Johannes Doerfert ef48436e62 [AttributeFuncs] Consider `noundef` in `typeIncompatible`
Drop `noundef` for return values that are replaced by void and make it
illegal to put `noundef` on a void value.

Reviewed By: fhahn

Differential Revision: https://reviews.llvm.org/D87306
2020-10-05 23:23:06 -05:00
Johannes Doerfert 2a078c3072 [AttributeFuncs] Consider `align` in `typeIncompatible`
Alignment attributes need to be dropped for non-pointer values.
This also introduces a check into the verifier to ensure you don't use
`align` on anything but a pointer. Test needed to be adjusted
accordingly.

Reviewed By: fhahn

Differential Revision: https://reviews.llvm.org/D87304
2020-10-05 23:23:05 -05:00
Sanjay Patel 149f5b573c [APFloat] convert SNaN to QNaN in convert() and raise Invalid signal
This is an alternate fix (see D87835) for a bug where a NaN constant
gets wrongly transformed into Infinity via truncation.
In this patch, we uniformly convert any SNaN to QNaN while raising
'invalid op'.
But we don't have a way to directly specify a 32-bit SNaN value in LLVM IR,
so those are always encoded/decoded by calling convert from/to 64-bit hex.

See D88664 for a clang fix needed to allow this change.

Differential Revision: https://reviews.llvm.org/D88238
2020-10-01 14:37:38 -04:00
Jamie Schmeiser 71124a9dbd Reland No.3: Add new hidden option -print-changed which only reports changes to IR
A new hidden option -print-changed is added along with code to support
printing the IR as it passes through the opt pipeline in the new pass
manager. Only those passes that change the IR are reported, with others
only having the banner reported, indicating that they did not change the
IR, were filtered out or ignored. Filtering of output via the
-filter-print-funcs is supported and a new supporting hidden option
-filter-passes is added. The latter takes a comma separated list of pass
names and filters the output to only show those passes in the list that
change the IR. The output can also be modified via the -print-module-scope
function.

The code introduces an abstract template base class that generalizes the
comparison of IRs that takes an IR representation as template parameter.
Derived classes provide overrides that provide an event based API
for generalized reporting of IRs as they are changed in the opt pipeline
through the new pass manager.

The first of several instantiations is provided that prints the IR
in a form similar to that produced by -print-after-all with the above
mentioned filtering capabilities. This version, and the others to
follow will be introduced at the upcoming developer's conference.

Reviewed By: aeubanks (Arthur Eubanks), yrouban (Yevgeny Rouban), ychen (Yuanfang Chen), MaskRay (Fangrui Song)

Differential Revision: https://reviews.llvm.org/D86360
2020-10-01 17:39:13 +00:00
Xiang1 Zhang 413577a879 [X86] Support Intel Key Locker
Key Locker provides a mechanism to encrypt and decrypt data with an AES key without having access
to the raw key value by converting AES keys into “handles”. These handles can be used to perform the
same encryption and decryption operations as the original AES keys, but they only work on the current
system and only until they are revoked. If software revokes Key Locker handles (e.g., on a reboot),
then any previous handles can no longer be used.

Reviewed By: craig.topper

Differential Revision: https://reviews.llvm.org/D88398
2020-09-30 18:08:45 +08:00
Simon Pilgrim 14ff38e235 [InstCombine] visitTrunc - trunc (lshr (sext A), C) --> (ashr A, C) non-uniform support
This came from @lebedev.ri's suggestion to use m_SpecificInt_ICMP for D88429 - since I was going to change the m_APInt to m_Constant for that patch I thought I would do it for the only other user of the APInt first.

I've added a ConstantExpr::getUMin helper - its trivial to add UMAX/SMIN/SMAX but thought I'd wait until we have use cases.

Differential Revision: https://reviews.llvm.org/D88475
2020-09-29 15:01:16 +01:00
Tres Popp eb9f7c28e5 Revert "OpaquePtr: Add type to sret attribute"
This reverts commit 55c4ff91bd.

Issues were introduced as discussed in https://reviews.llvm.org/D88241
where this change made previous bugs in the linker and BitCodeWriter
visible.
2020-09-29 10:31:04 +02:00
Robert Widmann 55f727306e [LLVM-C] Turn a ShuffleVector Constant Into a Getter.
It is not a good idea to expose raw constants in the LLVM C API. Replace this with an explicit getter.

Differential Revision: https://reviews.llvm.org/D88367
2020-09-26 17:32:57 -06:00
Craig Disselkoen 51cad041e0 C API: functions to get mask of a ShuffleVector
This commit fixes a regression (from LLVM 10 to LLVM 11 RC3) in the LLVM
C API.

Previously, commit 1ee6ec2bf removed the mask operand from the
ShuffleVector instruction, storing the mask data separately in the
instruction instead; this reduced the number of operands of
ShuffleVector from 3 to 2. AFAICT, this change unintentionally caused
a regression in the LLVM C API. Specifically, it is no longer possible
to get the mask of a ShuffleVector instruction through the C API. This
patch introduces new functions which together allow a C API user to get
the mask of a ShuffleVector instruction, restoring the functionality
which was previously available through LLVMGetOperand().

This patch also adds tests for this change to the llvm-c-test
executable, which involved adding support for InsertElement,
ExtractElement, and ShuffleVector itself (as well as constant vectors)
to echo.cpp. Previously, vector operations weren't tested at all in
echo.ll.

I also fixed some typos in comments and help-text nearby these changes,
which I happened to spot while developing this patch. Since the typo
fixes are technically unrelated other than being in the same files, I'm
happy to take them out if you'd rather they not be included in the patch.

Differential Revision: https://reviews.llvm.org/D88190
2020-09-25 16:01:05 -07:00
Adrian Prantl 137597d4f4 Add a verifier check that rejects non-distinct DISubprogram function
attachments. They would crash the backend, which expects all
DISubprograms that are not part of the type system to have a unit field.

Clang right before https://reviews.llvm.org/D79967 would generate this
kind of broken IR.

rdar://problem/69534688

Thanks to Fangrui for fixing an assembler test I had missed!

https://reviews.llvm.org/D88270
2020-09-25 12:04:46 -07:00
Matt Arsenault 55c4ff91bd OpaquePtr: Add type to sret attribute
Make the corresponding change that was made for byval in
b7141207a4. Like byval, this requires a
bulk update of the test IR tests to include the type before this can
be mandatory.
2020-09-25 14:07:30 -04:00
Adrian Prantl 8055ae31f4 Revert "Add a verifier check that rejects non-distinct DISubprogram function"
This reverts commit e17f52d623.

while investigating bot breakage.
2020-09-25 10:52:19 -07:00
Adrian Prantl e17f52d623 Add a verifier check that rejects non-distinct DISubprogram function
attachments. They would crash the backend, which expects all
DISubprograms that are not part of the type system to have a unit field.

Clang right before https://reviews.llvm.org/D79967 would generate this
kind of broken IR.

rdar://problem/69534688
2020-09-25 08:15:16 -07:00
Vedant Kumar dfc5a9eb57 [Instruction] Add dropLocation and updateLocationAfterHoist helpers
Introduce a helper which can be used to update the debug location of an
Instruction after the instruction is hoisted. This can be used to safely
drop a source location as recommended by the docs.

For more context, see the discussion in https://reviews.llvm.org/D60913.

Differential Revision: https://reviews.llvm.org/D85670
2020-09-24 15:00:04 -07:00
Matt Arsenault dc08185ca7 IR: Have byref imply dereferenceable
The langref already states it does, but this wasn't implemented. Also
covers inalloca and preallocated. Also helps fix a dependence on
pointer element types.
2020-09-24 09:57:28 -04:00
Matt Arsenault d65a7003c4 OpaquePtr: Add helpers for sret to mirror byval
Sret should really have a type parameter like byval does.
2020-09-24 09:57:28 -04:00
Roman Lebedev 7465da2077
[ConstantRange] Introduce getMinSignedBits() method
Similar to the ConstantRange::getActiveBits(), and to similarly-named
methods in APInt, returns the bitwidth needed to represent
the given signed constant range
2020-09-22 21:37:30 +03:00
Roman Lebedev 2ed9c4c70b
[ConstantRange] Introduce getActiveBits() method
Much like APInt::getActiveBits(), computes how many bits are needed
to be able to represent every value in this constant range,
treating the values as unsigned.
2020-09-22 21:37:29 +03:00
Roman Lebedev b38d897e80
[ConstantRange] binaryXor(): special-case binary complement case - the result is precise
Use the fact that `~X` is equivalent to `-1 - X`, which gives us
fully-precise answer, and we only need to special-handle the wrapped case.

This fires ~16k times for vanilla llvm test-suite + RawSpeed.
2020-09-22 21:37:29 +03:00
Simon Pilgrim 53f1748c13 ProfileSummary.cpp - use auto const& iterator in for-range loop to avoid copies. NFCI. 2020-09-21 16:54:26 +01:00
Matt Arsenault 751a6c5760 IR: Move denormal mode parsing from MachineFunction to Function
This was just inspecting the IR to begin with, and is useful to check
in some places in the IR.
2020-09-18 09:55:47 -04:00
Douglas Yung b03c2b8395 Revert "Re-land: Add new hidden option -print-changed which only reports changes to IR"
The test added in this commit is failing on Windows bots:

http://lab.llvm.org:8011/builders/llvm-clang-win-x-armv7l/builds/1269

This reverts commit f9e6d1edc0 and follow-up commit 6859d95ea2.
2020-09-17 01:32:29 -07:00
Jamie Schmeiser f9e6d1edc0 Re-land: Add new hidden option -print-changed which only reports changes to IR
A new hidden option -print-changed is added along with code to support
printing the IR as it passes through the opt pipeline in the new pass
manager. Only those passes that change the IR are reported, with others
only having the banner reported, indicating that they did not change the
IR, were filtered out or ignored. Filtering of output via the
-filter-print-funcs is supported and a new supporting hidden option
-filter-passes is added. The latter takes a comma separated list of pass
names and filters the output to only show those passes in the list that
change the IR. The output can also be modified via the -print-module-scope
function.

The code introduces a template base class that generalizes the comparison
of IRs that takes an IR representation as template parameter. The
constructor takes a series of lambdas that provide an event based API
for generalized reporting of IRs as they are changed in the opt pipeline
through the new pass manager.

The first of several instantiations is provided that prints the IR
in a form similar to that produced by -print-after-all with the above
mentioned filtering capabilities. This version, and the others to
follow will be introduced at the upcoming developer's conference.

Reviewed By: aeubanks (Arthur Eubanks), yrouban (Yevgeny Rouban), ychen (Yuanfang Chen)

Differential Revision: https://reviews.llvm.org/D86360
2020-09-16 17:25:18 +00:00