Commit Graph

30139 Commits

Author SHA1 Message Date
Kazu Hirata ba82c0b315 [llvm] Call *(Set|Map)::erase directly (NFC)
We can erase an item in a set or map without checking its membership
first.
2021-01-03 09:57:47 -08:00
Brandon Bergren 8f004471c2 [PowerPC] Add the LLVM triple for powerpcle [1/5]
Add a triple for powerpcle-*-*.

This is a little-endian encoding of the 32-bit PowerPC ABI, useful in certain niche situations:

1) A loader such as the FreeBSD loader which will be loading a little endian kernel. This is required for PowerPC64LE to load properly in pseries VMs.
Such a loader is implemented as a freestanding ELF32 LSB binary.

2) Userspace emulation of a 32-bit LE architecture such as x86 on 64-bit hosts such as PowerPC64LE with tools like box86 requires having a 32-bit LE toolchain and library set, as they operate by translating only the main binary and switching to native code when making library calls.

3) The Void Linux for PowerPC project is experimenting with running an entire powerpcle userland.

Reviewed By: MaskRay

Differential Revision: https://reviews.llvm.org/D93918
2021-01-02 12:17:22 -06:00
Kazu Hirata 171c5fd43e [llvm] Use llvm::erase_value and llvm::erase_if (NFC) 2021-01-02 09:24:15 -08:00
Roman Lebedev f4ea21947d
[NFCI][CodeGen] DwarfEHPrepare: don't actually pass DTU into simplifyCFG by default
also, don't verify DomTree unless we intend to maintain it.
This is a very dumb think-o, i guess i was even warned about it
by subconsciousness in 4b80647367950ba3da6a08260487fd0dbc50a9c5's
commit message..

Fixes a compile-time regression reported by Martin Storsjö
in post-commit review of 2461cdb417.
2021-01-02 14:38:52 +03:00
Yang Fan 471dec3801
[CodeGen][NFC] Fix a build warning due to an extra semicolon 2021-01-02 10:42:58 +08:00
Roman Lebedev 2461cdb417
[CodeGen][SimplifyCFG] Teach DwarfEHPrepare to preserve DomTree
Once the default for SimplifyCFG flips, we can no longer pass nullptr
instead of DomTree to SimplifyCFG, so we need to propagate it here.

We don't strictly need to actually preserve DomTree in DwarfEHPrepare,
but we might as well do it, since it's trivial.
2021-01-02 01:01:19 +03:00
Roman Lebedev e6b1a27fb9
[NFC][CodeGen] Split DwarfEHPrepare pass into an actual transform and an legacy-PM wrapper
This is consistent with the layout of other passes,
and simplifies further refinements regarding DomTree handling.

This is indended to be a NFC commit.
2021-01-02 01:01:19 +03:00
Roman Lebedev c38739ad8f
[NFC] clang-format the entire DwarfEHPrepare.cpp 2021-01-02 01:01:19 +03:00
Sanjay Patel c74e8539ff [Analysis] flatten enums for recurrence types
This is almost all mechanical search-and-replace and
no-functional-change-intended (NFC). Having a single
enum makes it easier to match/reason about the
reduction cases.

The goal is to remove `Opcode` from reduction matching
code in the vectorizers because that makes it harder to
adapt the code to handle intrinsics.

The code in RecurrenceDescriptor::AddReductionVar() is
the only place that required closer inspection. It uses
a RecurrenceDescriptor and a second InstDesc to sometimes
overwrite part of the struct. It seem like we should be
able to simplify that logic, but it's not clear exactly
which cmp+sel patterns that we are trying to handle/avoid.
2021-01-01 12:20:16 -05:00
Fangrui Song d1fd72343c Refactor how -fno-semantic-interposition sets dso_local on default visibility external linkage definitions
The idea is that the CC1 default for ELF should set dso_local on default
visibility external linkage definitions in the default -mrelocation-model pic
mode (-fpic/-fPIC) to match COFF/Mach-O and make output IR similar.

The refactoring is made available by 2820a2ca3a.

Currently only x86 supports local aliases. We move the decision to the driver.
There are three CC1 states:

* -fsemantic-interposition: make some linkages interposable and make default visibility external linkage definitions dso_preemptable.
* (default): selected if the target supports .Lfoo$local: make default visibility external linkage definitions dso_local
* -fhalf-no-semantic-interposition: if neither option is set or the target does not support .Lfoo$local: like -fno-semantic-interposition but local aliases are not used. So references can be interposed if not optimized out.

Add -fhalf-no-semantic-interposition to a few tests using the half-based semantic interposition behavior.
2020-12-31 13:59:45 -08:00
Juneyoung Lee 5cdf6ed744 [CodeGen] recognize select form of and/ors when splitting branch conditions
Recently a few patches are made to move towards using select i1 instead of and/or i1 to represent "a && b"/"a || b" in C/C++.
"a && b" in C/C++ does not evaluate b if a is false whereas 'and a, b' in IR evaluates b and uses its result regardless of the result of a.
This is problematic because it can cause miscompilation if b was an erroneous operation (https://llvm.org/pr48353).
In C/C++, the result is simply false because b is not evaluated, but in IR the result is poison.
The discussion at D93065 has more context about this.

This patch makes two branch-splitting optimizations (one in SelectionDAGBuilder, one in CodeGenPrepare) recognize
select form of and/or as well using m_LogicalAnd/Or.
Since it is CodeGen, I think this is semantically ok (at least as safe as what codegen already did).

Reviewed By: nikic

Differential Revision: https://reviews.llvm.org/D93853
2021-01-01 04:46:10 +09:00
Kazu Hirata 7bc76fd0ec [CodeGen] Construct SmallVector with iterator ranges (NFC) 2020-12-31 09:39:11 -08:00
Fangrui Song f731839584 [LowerEmuTls] Copy dso_local from <var> to __emutls_v.<var>
This effect is not testable until we drop the implied dso_local for ELF
static/PIE defined symbols from TargetMachine::shouldAssumeDSOLocal.
2020-12-30 16:11:32 -08:00
Juneyoung Lee 9b29610228 Use unary CreateShuffleVector if possible
As mentioned in D93793, there are quite a few places where unary `IRBuilder::CreateShuffleVector(X, Mask)` can be used
instead of `IRBuilder::CreateShuffleVector(X, Undef, Mask)`.
Let's update them.

Actually, it would have been more natural if the patches were made in this order:
(1) let them use unary CreateShuffleVector first
(2) update IRBuilder::CreateShuffleVector to use poison as a placeholder value (D93793)

The order is swapped, but in terms of correctness it is still fine.

Reviewed By: spatel

Differential Revision: https://reviews.llvm.org/D93923
2020-12-30 22:36:08 +09:00
Luo, Yuanke 981a0bd858 [X86] Add x86_amx type for intel AMX.
The x86_amx is used for AMX intrisics. <256 x i32> is bitcast to x86_amx when
it is used by AMX intrinsics, and x86_amx is bitcast to <256 x i32> when it
is used by load/store instruction. So amx intrinsics only operate on type x86_amx.
It can help to separate amx intrinsics from llvm IR instructions (+-*/).
Thank Craig for the idea. This patch depend on https://reviews.llvm.org/D87981.

Differential Revision: https://reviews.llvm.org/D91927
2020-12-30 13:52:13 +08:00
Yuanfang Chen 480936e741 Reland "[NewPM][CodeGen] Introduce CodeGenPassBuilder to help build codegen pipeline" (again)
This reverts commit 16c8f6e913 with fix.

-Wswitch catched an unhandled enum value due to recent commits in
TargetPassConfig.cpp.
2020-12-29 16:39:55 -08:00
Yuanfang Chen 16c8f6e913 Revert "Reland "[NewPM][CodeGen] Introduce CodeGenPassBuilder to help build codegen pipeline""
This reverts commit 21314940c4.

Build failure in some bots.
2020-12-29 16:29:07 -08:00
Yuanfang Chen 21314940c4 Reland "[NewPM][CodeGen] Introduce CodeGenPassBuilder to help build codegen pipeline"
This reverts commit 94427af60c (relands
4646de5d75 with fix).

Use "return std::move(AsmStreamer);" instead of "return AsmStreamer;" in
LVMTargetMachine::createMCStreamer. Unlike Clang, GCC seems having trouble
inserting a implicit lvalue->rvalue conversion.
2020-12-29 15:17:23 -08:00
Kazu Hirata 1e3ed09165 [CodeGen] Use llvm::append_range (NFC) 2020-12-28 19:55:16 -08:00
Yuanfang Chen 94427af60c Revert "[NewPM][CodeGen] Introduce CodeGenPassBuilder to help build codegen pipeline"
This reverts commit 4646de5d75.

Some bots have build failure.
2020-12-28 17:44:22 -08:00
Yuanfang Chen 4646de5d75 [NewPM][CodeGen] Introduce CodeGenPassBuilder to help build codegen pipeline
Following up on D67687.
Please refer to the RFC here http://lists.llvm.org/pipermail/llvm-dev/2020-July/143309.html

`CodeGenPassBuilder` is the NPM counterpart of `TargetPassConfig` with below differences.
- Debugging features (MIR print/verify, disable pass, start/stop-before/after, etc.) living in `TargetPassConfig` are moved to use PassInstrument as much as possible. (Implementation also lives in `TargetPassConfig.cpp`)
- `TargetPassConfig` is a polymorphic base (virtual inheritance) to build the target-dependent pipeline whereas `CodeGenPassBuilder` is the CRTP base/helper to implement the target-dependent pipeline. The motivation is flexibility for targets to customize the pipeline, inlining opportunity, and fits the overall NPM value semantics design.
- `TargetPassConfig` is a legacy immutable pass to declare hooks for targets to customize some target-independent codegen layer behavior. This is partially ported to TargetMachine::options. The rest, such as `createMachineScheduler/createPostMachineScheduler`, are left out for now. They should be implemented in LLVMTargetMachine in the future.

Reviewed By: arsenm, aeubanks

Differential Revision: https://reviews.llvm.org/D83608
2020-12-28 17:36:36 -08:00
Gabriel Hjort Åkerlund b9a7c89d43 [MIRPrinter] Fix incorrect output of unnamed stack names
The MIRParser expects unnamed stack entries to have empty names ('').
In case of unnamed alloca instructions, the MIRPrinter would output
'<unnamed alloca>', which caused the MIRParser to reject the generated
code.

Reviewed By: arsenm

Differential Revision: https://reviews.llvm.org/D93685
2020-12-28 18:01:40 +01:00
Chen Zheng 31c2b93d83 [MachineSink] add threshold in machinesink pass to reduce compiling time. 2020-12-27 23:23:07 -05:00
Kazu Hirata 789d250613 [CodeGen, Transforms] Use *Map::lookup (NFC) 2020-12-27 09:57:27 -08:00
Amara Emerson 7df3544e80 [GlobalISel] Fix assertion failures after "GlobalISel: Return APInt from getConstantVRegVal" landed.
APInt binary ops don't promote types but instead assert, which a combine was
relying on.
2020-12-26 23:51:44 -08:00
Kazu Hirata e457896a6e [CodeGen] Remove unused function hasInlineAsmMemConstraint (NFC)
The last use of the function was removed on Sep 13, 2010 in commit
1094c80281.
2020-12-24 09:17:58 -08:00
Kazu Hirata df812115e3 [CodeGen, Transforms] Use llvm::any_of (NFC) 2020-12-24 09:08:36 -08:00
Evgeniy Brevnov e0751234ef [CodeGen] Add "noreturn" attirbute to _Unwind_Resume
Currently 'resume' is lowered to _Unwind_Resume with out "noreturn" attribute. Semantically _Unwind_Resume  library call is expected to never return and should be marked as such. Though I didn't find any changes in behavior of existing tests there will be a difference once https://reviews.llvm.org/D79485 lands.

I was not able to come up with the test case anything better than just checking for presence of "noreturn" attribute. Please let me know if there is a better way to test the change.

Reviewed By: xbolva00

Differential Revision: https://reviews.llvm.org/D93682
2020-12-24 18:14:18 +07:00
Layton Kifer d29f93bda5 [DAGCombiner] Don't create sexts of deleted xors when they were in-visit replaced
Fixes a bug introduced by D91589.

When folding `(sext (not i1 x)) -> (add (zext i1 x), -1)`, we try to replace the not first when possible. If we replace the not in-visit, then the now invalidated node will be returned, and subsequently we will return an invalid sext. In cases where the not is replaced in-visit we can simply return SDValue, as the not in the current sext should have already been replaced.

Thanks @jgorbe, for finding the below reproducer.

The following reduced test case crashes clang when built with `clang -O1 -frounding-math`:

```
template <class> class a {
  int b() { return c == 0.0 ? 0 : -1; }
  int c;
};
template class a<long>;
```

A debug build of clang produces this "assertion failed" error:
```
clang: /home/jgorbe/code/llvm/llvm/lib/CodeGen/SelectionDAG/DAGCombiner.cpp:264: void {anonymous}::DAGCombiner::AddToWorklist(llvm::
SDNode*): Assertion `N->getOpcode() != ISD::DELETED_NODE && "Deleted Node added to Worklist"' failed.
```

Reviewed By: spatel

Differential Revision: https://reviews.llvm.org/D93274
2020-12-23 16:16:26 -08:00
Sriraman Tallam 34e70d722d Append ".__part." to every basic block section symbol.
Every basic block section symbol created by -fbasic-block-sections will contain
".__part." to know that this symbol corresponds to a basic block fragment of
the function.

This patch solves two problems:

a) Like D89617, we want function symbols with suffixes to be properly qualified
   so that external tools like profile aggregators know exactly what this
   symbol corresponds to.
b) The current basic block naming just adds a ".N" to the symbol name where N is
   some integer. This collides with how clang creates __cxx_global_var_init.N.
   clang creates these symbol names to call constructor functions and basic
   block symbol naming should not use the same style.

Fixed all the test cases and added an extra test for __cxx_global_var_init
breakage.

Differential Revision: https://reviews.llvm.org/D93082
2020-12-23 11:35:44 -08:00
Matt Arsenault 581d13f8ae GlobalISel: Return APInt from getConstantVRegVal
Returning int64_t was arbitrarily limiting for wide integer types, and
the functions should handle the full generality of the IR.

Also changes the full form which returns the originally defined
vreg. Add another wrapper for the common case of just immediately
converting to int64_t (arguably this would be useful for the full
return value case as well).

One possible issue with this change is some of the existing uses did
break without conversion to getConstantVRegSExtVal, and it's possible
some without adequate test coverage are now broken.
2020-12-22 22:23:58 -05:00
Matt Arsenault 5bec082834 VirtRegMap: Use Register 2020-12-22 20:56:14 -05:00
Arthur O'Dwyer 22cf54a7fb Replace `T(x)` with `reinterpret_cast<T>(x)` everywhere it means reinterpret_cast. NFC.
Differential Revision: https://reviews.llvm.org/D76572
2020-12-22 19:54:29 -05:00
Sjoerd Meijer 9a6de74d5a [MachineLICM] Add llvm debug messages to SinkIntoLoop. NFC.
I am investigating sinking instructions back into the loop under high
register pressure. This is just a first NFC step to add some debug
messages that allows tracing of the decision making.
2020-12-22 09:19:43 +00:00
Pavel Labath 8d75d902a9 [DebugInfo] Don't use DW_OP_implicit_value for fragments
Currently using DW_OP_implicit_value in fragments produces invalid DWARF
expressions. (Such a case can occur in complex floats, for example.)

This problem manifests itself as a missing DW_OP_piece operation after
the last fragment. This happens because the function for printing
constant float value skips printing the accompanying DWARF expression,
as that would also print DW_OP_stack_value (which is not desirable in
this case). However, this also results in DW_OP_piece being skipped.

The reason that DW_OP_piece is missing only for the last piece is that
the act of printing the next fragment corrects this. However, it does
that for the wrong reason -- the code emitting this DW_OP_piece thinks
that the previous fragment was missing, and so it thinks that it needs
to skip over it in order to be able to print itself.

In a simple scenario this works out, but it's likely that in a more
complex setup (where some pieces are in fact missing), this logic would
go badly wrong. In a simple setup gdb also seems to not mind the fact
that the DW_OP_piece is missing, but it would also likely not handle
more complex use cases.

For this reason, this patch disables the usage of DW_OP_implicit_value
in the frament scenario (we will use DW_OP_const*** instead), until we
figure out the right way to deal with this. This guarantees that we
produce valid expressions, and gdb can handle both kinds of inputs
anyway.

Differential Revision: https://reviews.llvm.org/D92013
2020-12-22 10:07:47 +01:00
Bing1 Yu e8ade4569b [LegalizeType] When LegalizeType procedure widens a masked_gather, set MemoryType's EltNum equal to Result's EltNum
When LegalizeType procedure widens a masked_gather, set MemoryType's EltNum equal to Result's EltNum.

As I mentioned in https://reviews.llvm.org/D91092, in previous code, If we have a v17i32's masked_gather in avx512, we widen it to a v32i32's masked_gather with a v17i32's MemoryType. When the SplitVecRes_MGATHER process this v32i32's masked_gather, GetSplitDestVTs will assert fail since what you are going to split is v17i32.

Reviewed By: craig.topper

Differential Revision: https://reviews.llvm.org/D93610
2020-12-22 13:27:38 +08:00
Fangrui Song d9a0c40bce [MC] Split MCContext::createTempSymbol, default AlwaysAddSuffix to true, and add comments
CanBeUnnamed is rarely false. Splitting to a createNamedTempSymbol makes the
intention clearer and matches the direction of reverted r240130 (to drop the
unneeded parameters).

No behavior change.
2020-12-21 14:04:13 -08:00
Denis Antrushin 6f45049fb6 [Statepoints] Disable VReg lowering for values used on exception path of invoke.
Currently we lower invokes the same way as usual calls, e.g.:

V1 = STATEPOINT ... V (tied-def 0)

But this is incorrect is V1 is used on exceptional path.
By LLVM rules V1 neither dominates its uses in landing pad, nor
its live range is live on entry to landing pad. So compiler is
allowed to do various weird transformations like splitting live
range after statepoint and use split LR in catch block.

Until (and if) we find better solution to this problem, let's
use old lowering (spilling) for those values which are used on
exceptional path and allow VReg lowering for values used only
on normal path.

Differential Revision: https://reviews.llvm.org/D93449
2020-12-21 20:27:05 +07:00
Fangrui Song 1635dea266 [AsmPrinter] Replace a reachable report_fatal_error with MCContext::reportError 2020-12-20 23:45:49 -08:00
Pushpinder Singh e2303a448e [FastRA] Fix handling of bundled MIs
Fast register allocator skips bundled MIs, as the main assignment
loop uses MachineBasicBlock::iterator (= MachineInstrBundleIterator)
This was causing SIInsertWaitcnts to crash which expects all
instructions to have registers assigned.

This patch makes sure to set everything inside bundle to the same
assignments done on BUNDLE header.

Reviewed By: qcolombet

Differential Revision: https://reviews.llvm.org/D90369
2020-12-21 02:10:55 -05:00
Chen Zheng 4dce7c2e20 [MachineLICM] delete dead flag if the duplicated def outside of loop is dead.
Fixup dead flags for CSE-ed instructions.

Reviewed By: arsenm

Differential Revision: https://reviews.llvm.org/D92557
2020-12-20 19:26:22 -05:00
Kazu Hirata 3285ee143b [Analysis, IR, CodeGen] Use llvm::erase_if (NFC) 2020-12-20 09:19:35 -08:00
Kazu Hirata 805d59593f [Analysis, CodeGen, IR] Use contains (NFC) 2020-12-18 19:08:17 -08:00
Chih-Ping Chen 5f75dcf571 [DebugInfo] Support Fortran 'use <external module>' statement.
The main change is to add a 'IsDecl' field to DIModule so
that when IsDecl is set to true, the debug info entry generated
for the module would be marked as a declaration. That way, the debugger
would look up the definition of the module in the gloabl scope.

Please see the comments in llvm/test/DebugInfo/X86/dimodule.ll
for what the debug info entries would look like.

Differential Revision: https://reviews.llvm.org/D93462
2020-12-18 13:10:57 -05:00
Craig Blackmore 698ae90f30 [RegisterScavenging] Fix assert in scavengeRegisterBackwards
According to the documentation, if a spill is required to make a
register available and AllowSpill is false, then NoRegister should be
returned, however, this scenario was actually triggering an assertion
failure.

This patch moves the assertion after the handling of AllowSpill.

Authored by: Lewis Revill

Reviewed By: arsenm

Differential Revision: https://reviews.llvm.org/D92104
2020-12-18 16:57:05 +00:00
Matt Arsenault fd0f5fb8de PEI: Only call updateLiveness once per function
This only needs to be called once for the function, and it visits all
the necessary blocks in the function. It looks like
631f6b888c accidentally moved this into
the loop over all save blocks.
2020-12-18 11:02:28 -05:00
Bjorn Pettersson a89d751fb4 Add intrinsics for saturating float to int casts
This patch adds support for the fptoui.sat and fptosi.sat intrinsics,
which provide basically the same functionality as the existing fptoui
and fptosi instructions, but will saturate (or return 0 for NaN) on
values unrepresentable in the target type, instead of returning
poison. Related mailing list discussion can be found at:
https://groups.google.com/d/msg/llvm-dev/cgDFaBmCnDQ/CZAIMj4IBAAJ

The intrinsics have overloaded source and result type and support
vector operands:

    i32 @llvm.fptoui.sat.i32.f32(float %f)
    i100 @llvm.fptoui.sat.i100.f64(double %f)
    <4 x i32> @llvm.fptoui.sat.v4i32.v4f16(half %f)
    // etc

On the SelectionDAG layer two new ISD opcodes are added,
FP_TO_UINT_SAT and FP_TO_SINT_SAT. These opcodes have two operands
and one result. The second operand is an integer constant specifying
the scalar saturation width. The idea here is that initially the
second operand and the scalar width of the result type are the same,
but they may change during type legalization. For example:

    i19 @llvm.fptsi.sat.i19.f32(float %f)
    // builds
    i19 fp_to_sint_sat f, 19
    // type legalizes (through integer result promotion)
    i32 fp_to_sint_sat f, 19

I went for this approach, because saturated conversion does not
compose well. There is no good way of "adjusting" a saturating
conversion to i32 into one to i19 short of saturating twice.
Specifying the saturation width separately allows directly saturating
to the correct width.

There are two baseline expansions for the fp_to_xint_sat opcodes. If
the integer bounds can be exactly represented in the float type and
fminnum/fmaxnum are legal, we can expand to something like:

    f = fmaxnum f, FP(MIN)
    f = fminnum f, FP(MAX)
    i = fptoxi f
    i = select f uo f, 0, i # unnecessary if unsigned as 0 = MIN

If the bounds cannot be exactly represented, we expand to something
like this instead:

    i = fptoxi f
    i = select f ult FP(MIN), MIN, i
    i = select f ogt FP(MAX), MAX, i
    i = select f uo f, 0, i # unnecessary if unsigned as 0 = MIN

It should be noted that this expansion assumes a non-trapping fptoxi.

Initial tests are for AArch64, x86_64 and ARM. This exercises all of
the scalar and vector legalization. ARM is included to test float
softening.

Original patch by @nikic and @ebevhan (based on D54696).

Differential Revision: https://reviews.llvm.org/D54749
2020-12-18 11:09:41 +01:00
Rong Xu 3733463dbb [IR][PGO] Add hot func attribute and use hot/cold attribute in func section
Clang FE currently has hot/cold function attribute. But we only have
cold function attribute in LLVM IR.

This patch adds support of hot function attribute to LLVM IR.  This
attribute will be used in setting function section prefix/suffix.
Currently .hot and .unlikely suffix only are added in PGO (Sample PGO)
compilation (through isFunctionHotInCallGraph and
isFunctionColdInCallGraph).

This patch changes the behavior. The new behavior is:
(1) If the user annotates a function as hot or isFunctionHotInCallGraph
    is true, this function will be marked as hot. Otherwise,
(2) If the user annotates a function as cold or
    isFunctionColdInCallGraph is true, this function will be marked as
    cold.

The changes are:
(1) user annotated function attribute will used in setting function
    section prefix/suffix.
(2) hot attribute overwrites profile count based hotness.
(3) profile count based hotness overwrite user annotated cold attribute.

The intention for these changes is to provide the user a way to mark
certain function as hot in cases where training input is hard to cover
all the hot functions.

Differential Revision: https://reviews.llvm.org/D92493
2020-12-17 18:41:12 -08:00
Layton Kifer 385e9a2a04 [DAGCombiner] Improve shift by select of constant
Clean up a TODO, to support folding a shift of a constant by a
select of constants, on targets with different shift operand sizes.

Reviewed By: RKSimon, lebedev.ri

Differential Revision: https://reviews.llvm.org/D90349
2020-12-18 02:21:42 +00:00
dfukalov 9ed8e0caab [NFC] Reduce include files dependency and AA header cleanup (part 2).
Continuing work started in https://reviews.llvm.org/D92489:

Removed a bunch of includes from "AliasAnalysis.h" and "LoopPassManager.h".

Reviewed By: RKSimon

Differential Revision: https://reviews.llvm.org/D92852
2020-12-17 14:04:48 +03:00
Krasimir Georgiev e71a4cc207 fix a -Wunused-variable warning in release build 2020-12-17 11:52:00 +01:00
Barry Revzin 92310454bf Make LLVM build in C++20 mode
Part of the <=> changes in C++20 make certain patterns of writing equality
operators ambiguous with themselves (sorry!).
This patch goes through and adjusts all the comparison operators such that
they should work in both C++17 and C++20 modes. It also makes two other small
C++20-specific changes (adding a constructor to a type that cases to be an
aggregate, and adding casts from u8 literals which no longer have type
const char*).

There were four categories of errors that this review fixes.
Here are canonical examples of them, ordered from most to least common:

// 1) Missing const
namespace missing_const {
    struct A {
    #ifndef FIXED
        bool operator==(A const&);
    #else
        bool operator==(A const&) const;
    #endif
    };

    bool a = A{} == A{}; // error
}

// 2) Type mismatch on CRTP
namespace crtp_mismatch {
    template <typename Derived>
    struct Base {
    #ifndef FIXED
        bool operator==(Derived const&) const;
    #else
        // in one case changed to taking Base const&
        friend bool operator==(Derived const&, Derived const&);
    #endif
    };

    struct D : Base<D> { };

    bool b = D{} == D{}; // error
}

// 3) iterator/const_iterator with only mixed comparison
namespace iter_const_iter {
    template <bool Const>
    struct iterator {
        using const_iterator = iterator<true>;

        iterator();

        template <bool B, std::enable_if_t<(Const && !B), int> = 0>
        iterator(iterator<B> const&);

    #ifndef FIXED
        bool operator==(const_iterator const&) const;
    #else
        friend bool operator==(iterator const&, iterator const&);
    #endif
    };

    bool c = iterator<false>{} == iterator<false>{} // error
          || iterator<false>{} == iterator<true>{}
          || iterator<true>{} == iterator<false>{}
          || iterator<true>{} == iterator<true>{};
}

// 4) Same-type comparison but only have mixed-type operator
namespace ambiguous_choice {
    enum Color { Red };

    struct C {
        C();
        C(Color);
        operator Color() const;
        bool operator==(Color) const;
        friend bool operator==(C, C);
    };

    bool c = C{} == C{}; // error
    bool d = C{} == Red;
}

Differential revision: https://reviews.llvm.org/D78938
2020-12-17 10:44:10 +00:00
Simon Pilgrim cdb692ee0c [X86] Add X86ISD::SUBV_BROADCAST_LOAD and begin removing X86ISD::SUBV_BROADCAST (PR38969)
Subvector broadcasts are only load instructions, yet X86ISD::SUBV_BROADCAST treats them more generally, requiring a lot of fallback tablegen patterns.

This initial patch replaces constant vector lowering inside lowerBuildVectorAsBroadcast with direct X86ISD::SUBV_BROADCAST_LOAD loads which helps us merge a number of equivalent loads/broadcasts.

As well as general plumbing/analysis additions for SUBV_BROADCAST_LOAD, I needed to wrap SelectionDAG::makeEquivalentMemoryOrdering so it can handle result chains from non generic LoadSDNode nodes.

Later patches will continue to replace X86ISD::SUBV_BROADCAST usage.

Differential Revision: https://reviews.llvm.org/D92645
2020-12-17 10:25:25 +00:00
QingShan Zhang ebdd20f430 Expand the fp_to_int/int_to_fp/fp_round/fp_extend as libcall for fp128
X86 and AArch64 expand it as libcall inside the target. And PowerPC also
want to expand them as libcall for P8. So, propose an implement in the
legalizer to common the logic and remove the code for X86/AArch64 to
avoid the duplicate code.

Reviewed By: Craig Topper

Differential Revision: https://reviews.llvm.org/D91331
2020-12-17 07:59:30 +00:00
Fangrui Song c70f36865e Use basic_string::find(char) instead of basic_string::find(const char *s, size_type pos=0)
Many (StringRef) cannot be detected by clang-tidy performance-faster-string-find.
2020-12-16 23:28:32 -08:00
Xiang1 Zhang 39584ae5b5 [Debugify] Support checking Machine IR debug info
Add mir-check-debug pass to check MIR-level debug info.

For IR-level, currently, LLVM have debugify + check-debugify to generate
and check debug IR. Much like the IR-level pass debugify, mir-debugify
inserts sequentially increasing line locations to each MachineInstr in a
Module, But there is no equivalent MIR-level check-debugify pass, So now
we support it at "mir-check-debug".

Reviewed By: djtodoro

Differential Revision: https://reviews.llvm.org/D91595
2020-12-16 22:17:25 -08:00
Kazu Hirata 5501b92957 [IR, CodeGen] Use llvm::is_contained (NFC) 2020-12-16 21:30:44 -08:00
Xiang1 Zhang 1e42ad9d62 Revert "[Debugify] Support checking Machine IR debug info"
This reverts commit 50aaa8c274.
2020-12-16 20:12:33 -08:00
Xiang1 Zhang 50aaa8c274 [Debugify] Support checking Machine IR debug info
Add mir-check-debug pass to check MIR-level debug info.

For IR-level, currently, LLVM have debugify + check-debugify to generate
and check debug IR. Much like the IR-level pass debugify, mir-debugify
inserts sequentially increasing line locations to each MachineInstr in a
Module, But there is no equivalent MIR-level check-debugify pass, So now
we support it at "mir-check-debug".

Reviewed By: djtodoro

Differential Revision: https://reviews.llvm.org/D91595
2020-12-16 18:04:05 -08:00
Guozhi Wei 687e80be7f [MBP] Add whole chain to BlockFilterSet instead of individual BB
Currently we add individual BB to BlockFilterSet if its frequency satisfies

  LoopFreq / Freq <= LoopToColdBlockRatio

LoopFreq is edge frequency from outside to loop header.
LoopToColdBlockRatio is a command line parameter.

It doesn't make sense since we always layout whole chain, not individual BBs.

It may also cause a tricky problem. Sometimes it is possible that the LoopFreq
of an inner loop is smaller than LoopFreq of outer loop. So a BB can be in
BlockFilterSet of inner loop, but not in BlockFilterSet of outer loop,
like .cold in the test case. So it is added to the chain of inner loop. When
work on the outer loop, .cold is not added to BlockFilterSet, so the edge to
successor .problem is not counted in UnscheduledPredecessors of .problem chain.
But other blocks in the inner loop are added BlockFilterSet, so the whole inner
loop chain can be layout, and markChainSuccessors is called to decrease
UnscheduledPredecessors of following chains. markChainSuccessors calls
markBlockSuccessors for every BB, even it is not in BlockFilterSet, like .cold,
so .problem chain's UnscheduledPredecessors is decreased, but this edge was not
counted on in fillWorkLists, so .problem chain's UnscheduledPredecessors
becomes 0 when it still has an unscheduled predecessor .pred! And it causes
problems in following various successor BB selection algorithms.

Differential Revision: https://reviews.llvm.org/D89088
2020-12-16 15:45:47 -08:00
Bardia Mahjour 6eff12788e [DDG] Data Dependence Graph - DOT printer - recommit
This is being recommitted to try and address the MSVC complaint.

This patch implements a DDG printer pass that generates a graph in
the DOT description language, providing a more visually appealing
representation of the DDG. Similar to the CFG DOT printer, this
functionality is provided under an option called -dot-ddg and can
be generated in a less verbose mode under -dot-ddg-only option.

Reviewed By: Meinersbur

Differential Revision: https://reviews.llvm.org/D90159
2020-12-16 12:37:36 -05:00
diggerlin a1e1dcabe4 [XCOFF][AIX] Emit EH information in traceback table
SUMMARY:

In order for the runtime on AIX to find the compact unwind section(EHInfo table),
we would need to set the following on the traceback table:

The 6th byte's longtbtable field to true to signal there is an Extended TB Table Flag.
The Extended TB Table Flag to be 0x08 to signal there is an exception handling info presents.
Emit the offset between ehinfo TC entry and TOC base after all other optional portions of traceback table.

The patch is authored by Jason Liu.

Reviewers: David Tenty, Digger Lin
Differential Revision: https://reviews.llvm.org/D92766
2020-12-16 09:34:59 -05:00
Matt Arsenault 60eba8161b RegisterCoalescer: Remove phi-only subranges when erasing identity copies
Undef subranges are not present in the live range values, except when
they cross block boundaries. In this situation, a identity copy is
inside a loop, and one of the lanes is undefined. It only appears
alive inside the loop due to the copy. Once the copy was erased, it
would leave behind a segment inside the loop body with no
corresponding def anywhere in the program.

When RenameIndependentSubregs processed this dummy interval, it would
introduce a "Multiple connected components in live interval" verifier
error when IMPLICIT_DEFs were added to the other two blocks. I believe
there is a missing verifier check for this type of dummy interval.

I have found additional cases from the same fundamental problem in
other areas I haven't managed to fix yet (e.g. the commented out
prune_subrange_phi_value_* cases).
2020-12-15 17:36:32 -05:00
Fangrui Song 8c4e55762d [docs][unittest][Go][StackProtector] Migrate deprecated DebugInfo::get to DILocation::get 2020-12-15 14:17:04 -08:00
Matt Arsenault e7e7d371fd GlobalISel: Fix generic handling of single outgoing call arguments
Simply call the argument handler like is done for the incoming
case. This will allow removal of hacks in the AMDGPU call lowering in
a future change.
2020-12-15 17:00:27 -05:00
Paul Walker 6d35bd1d48 [CodeGenPrepare] Update optimizeGatherScatterInst for scalable vectors.
optimizeGatherScatterInst does nothing specific to fixed length vectors
but uses FixedVectorType to extract the number of elements.  This patch
simply updates the code to use VectorType and getElementCount instead.

For testing I just copied Transforms/CodeGenPrepare/X86/gather-scatter-opt.ll
replacing `<4 x ` with `<vscale x 4`.

Differential Revision: https://reviews.llvm.org/D92572
2020-12-15 10:57:51 +00:00
Amara Emerson a69b76c500 [GlobalISel][IRTranslator] Ensure branch probabilities are added when translating invoke edges.
This uses a straightforward port of findUnwindDestinations() from SelectionDAG.

Differential Revision: https://reviews.llvm.org/D93256
2020-12-14 23:36:54 -08:00
Nico Weber a852ee199c Reland "[MachineDebugify] Insert synthetic DBG_VALUE instructions"
This reverts commit 841f9c937f.
The change landed many months ago; something else broke those tests.
2020-12-14 22:34:23 -05:00
Nico Weber 841f9c937f Revert "[MachineDebugify] Insert synthetic DBG_VALUE instructions"
This reverts commit 2a5675f11d.
The tests it adds fail: https://reviews.llvm.org/D78135#2453736
2020-12-14 22:14:48 -05:00
Nico Weber da2551f3d1 Revert "[Debugify] Support checking Machine IR debug info"
This reverts commit c4d2d4337d.
Necessary to revert 2a5675f11d.
2020-12-14 22:14:48 -05:00
Qiu Chaofan 38b4442198 [NFC] [Legalizer] Use common method for expanding fp-to-int operands
Reviewed By: RKSimon, steven.zhang

Differential Revision: https://reviews.llvm.org/D92481
2020-12-15 10:45:40 +08:00
Xiang1 Zhang c4d2d4337d [Debugify] Support checking Machine IR debug info
Add mir-check-debug pass to check MIR-level debug info.

For IR-level, currently, LLVM have debugify + check-debugify to generate
and check debug IR. Much like the IR-level pass debugify, mir-debugify
inserts sequentially increasing line locations to each MachineInstr in a
Module, But there is no equivalent MIR-level check-debugify pass, So now
we support it at "mir-check-debug".

Reviewed By: djtodoro

Differential Revision: https://reviews.llvm.org/D91595
2020-12-14 17:53:46 -08:00
Xiang1 Zhang fc0f4010bb Revert "[Debugify] Support checking Machine IR debug info"
This reverts commit 57a3d9ec4a.
2020-12-14 17:48:49 -08:00
Xiang1 Zhang 57a3d9ec4a [Debugify] Support checking Machine IR debug info
Add mir-check-debug pass to check MIR-level debug info.

For IR-level, currently, LLVM have debugify + check-debugify to generate
and check debug IR. Much like the IR-level pass debugify, mir-debugify
inserts sequentially increasing line locations to each MachineInstr in a
Module, But there is no equivalent MIR-level check-debugify pass, So now
we support it at "mir-check-debug".

Reviewed By: djtodoro

Differential Revision: https://reviews.llvm.org/D95195
2020-12-14 17:38:01 -08:00
Bardia Mahjour a29ecca781 Revert "[DDG] Data Dependence Graph - DOT printer"
This reverts commit fd4a10732c, to
investigate the failure on windows: http://lab.llvm.org:8011/#/builders/127/builds/3274
2020-12-14 16:54:20 -05:00
Bardia Mahjour fd4a10732c [DDG] Data Dependence Graph - DOT printer
This patch implements a DDG printer pass that generates a graph in
the DOT description language, providing a more visually appealing
representation of the DDG. Similar to the CFG DOT printer, this
functionality is provided under an option called -dot-ddg and can
be generated in a less verbose mode under -dot-ddg-only option.

Differential Revision: https://reviews.llvm.org/D90159
2020-12-14 16:41:14 -05:00
Matt Arsenault 2e0e03c6a0 OpaquePtr: Require byval on x86_intrcc parameter 0
Currently the backend special cases x86_intrcc and treats the first
parameter as byval. Make the IR require byval for this parameter to
remove this special case, and avoid the dependence on the pointee
element type.

Fixes bug 46672.

I'm not sure the IR is enforcing all the calling convention
constraints. clang seems to ignore the attribute for empty parameter
lists, but the IR tolerates it.
2020-12-14 16:34:37 -05:00
Zequan Wu b6b522c4db [NFC] cleanup cg-profile emission on TargetLowerinng
Differential Revision: https://reviews.llvm.org/D93150
2020-12-14 13:07:44 -08:00
Guozhi Wei d50d7c37a1 [MBP] Prevent rotating a chain contains entry block
The entry block should always be the first BB in a function.
So we should not rotate a chain contains the entry block.

Differential Revision: https://reviews.llvm.org/D92882
2020-12-14 12:48:55 -08:00
Kerry McLaughlin c5ced82c8e [SVE][CodeGen] Lower scalable floating-point vector reductions
Changes in this patch:
-  Minor changes to the LowerVECREDUCE_SEQ_FADD function added by @cameron.mcinally
   to also work for scalable types
- Added TableGen patterns for FP reductions with unpacked types (nxv2f16, nxv4f16 & nxv2f32)
- Asserts added to expandFMINNUM_FMAXNUM & expandVecReduceSeq for scalable types

Reviewed By: cameron.mcinally

Differential Revision: https://reviews.llvm.org/D93050
2020-12-14 11:45:42 +00:00
QingShan Zhang 08e287aaf3 [PowerPC][FP128] Fix the incorrect signature for math library call
The runtime library has two family library implementation for ppc_fp128 and fp128.
For IBM Long double(ppc_fp128), it is suffixed with 'l', i.e(sqrtl). For
IEEE Long double(fp128), it is suffixed with "ieee128" or "f128".
We miss to map several libcall for IEEE Long double.

Reviewed By: qiucf

Differential Revision: https://reviews.llvm.org/D91675
2020-12-14 07:52:56 +00:00
Chen Zheng 4830d458dd [MachineCombiner][NFC] Add MustReduceRegisterPressure goal
add a new goal MustReduceRegisterPressure for machine combiner pass.

PowerPC will use this new goal to do some register pressure related optimization.

Reviewed By: spatel

Differential Revision: https://reviews.llvm.org/D92068
2020-12-14 00:02:42 -05:00
Kazu Hirata ee5b5b7a35 [CodeGen] Use llvm::erase_value (NFC) 2020-12-13 20:05:48 -08:00
Amara Emerson 21de99d43c [[GlobalISel][IRTranslator] Fix a crash when the use of an extractvalue is a non-dominated metadata use.
We don't expect uses to come before defs in the CFG, so allocateVRegs() asserted.

Fixes PR48211
2020-12-12 14:58:54 -08:00
diggerlin 997d286f2d [AIX][XCOFF] emit traceback table for function in aix
SUMMARY:
 1. added a new option -xcoff-traceback-table to control whether generate traceback table for function.
 2. implement the functionality of emit traceback table of a function.

Reviewers: hubert.reinterpretcast, Jason Liu
Differential Revision: https://reviews.llvm.org/D92398
2020-12-11 17:50:25 -05:00
Fangrui Song b5ad32ef5c Migrate deprecated DebugLoc::get to DILocation::get
This migrates all LLVM (except Kaleidoscope and
CodeGen/StackProtector.cpp) DebugLoc::get to DILocation::get.

The CodeGen/StackProtector.cpp usage may have a nullptr Scope
and can trigger an assertion failure, so I don't migrate it.

Reviewed By: #debug-info, dblaikie

Differential Revision: https://reviews.llvm.org/D93087
2020-12-11 12:45:22 -08:00
Joe Ellis d863a0ddeb [SelectionDAG] Implement SplitVecOp_INSERT_SUBVECTOR
This function is needed for when it is necessary to split the subvector
operand of an llvm.experimental.vector.insert call. Splitting the
subvector operand means performing two insertions: one inserting the
lower part of the split subvector into the destination vector, and
another for inserting the upper part.

Through experimenting, it seems quite rare to need split the subvector
operand, but this is necessary to avoid assertion errors.

Differential Revision: https://reviews.llvm.org/D92760
2020-12-11 11:07:59 +00:00
David Sherwood 9b76160e53 [Support] Introduce a new InstructionCost class
This is the first in a series of patches that attempts to migrate
existing cost instructions to return a new InstructionCost class
in place of a simple integer. This new class is intended to be
as light-weight and simple as possible, with a full range of
arithmetic and comparison operators that largely mirror the same
sets of operations on basic types, such as integers. The main
advantage to using an InstructionCost is that it can encode a
particular cost state in addition to a value. The initial
implementation only has two states - Normal and Invalid - but these
could be expanded over time if necessary. An invalid state can
be used to represent an unknown cost or an instruction that is
prohibitively expensive.

This patch adds the new class and changes the getInstructionCost
interface to return the new class. Other cost functions, such as
getUserCost, etc., will be migrated in future patches as I believe
this to be less disruptive. One benefit of this new class is that
it provides a way to unify many of the magic costs in the codebase
where the cost is set to a deliberately high number to prevent
optimisations taking place, e.g. vectorization. It also provides
a route to represent the extremely high, and unknown, cost of
scalarization of scalable vectors, which is not currently supported.

Differential Revision: https://reviews.llvm.org/D91174
2020-12-11 08:12:54 +00:00
Hongtao Yu 705a4c149d [CSSPGO] Pseudo probe encoding and emission.
This change implements pseudo probe encoding and emission for CSSPGO. Please see RFC here for more context: https://groups.google.com/g/llvm-dev/c/1p1rdYbL93s

Pseudo probes are in the form of intrinsic calls on IR/MIR but they do not turn into any machine instructions. Instead they are emitted into the binary as a piece of data in standalone sections.  The probe-specific sections are not needed to be loaded into memory at execution time, thus they do not incur a runtime overhead. 

**ELF object emission**

The binary data to emit are organized as two ELF sections, i.e, the `.pseudo_probe_desc` section and the `.pseudo_probe` section. The `.pseudo_probe_desc` section stores a function descriptor for each function and the `.pseudo_probe` section stores the actual probes, each fo which corresponds to an IR basic block or an IR function callsite. A function descriptor is stored as a module-level metadata during the compilation and is serialized into the object file during object emission.

Both the probe descriptors and pseudo probes can be emitted into a separate ELF section per function to leverage the linker for deduplication.  A `.pseudo_probe` section shares the same COMDAT group with the function code so that when the function is dead, the probes are dead and disposed too. On the contrary, a `.pseudo_probe_desc` section has its own COMDAT group. This is because even if a function is dead, its probes may be inlined into other functions and its descriptor is still needed by the profile generation tool.

The format of `.pseudo_probe_desc` section looks like:

```
.section   .pseudo_probe_desc,"",@progbits
.quad   6309742469962978389  // Func GUID
.quad   4294967295           // Func Hash
.byte   9                    // Length of func name
.ascii  "_Z5funcAi"          // Func name
.quad   7102633082150537521
.quad   138828622701
.byte   12
.ascii  "_Z8funcLeafi"
.quad   446061515086924981
.quad   4294967295
.byte   9
.ascii  "_Z5funcBi"
.quad   -2016976694713209516
.quad   72617220756
.byte   7
.ascii  "_Z3fibi"
```

For each `.pseudoprobe` section, the encoded binary data consists of a single function record corresponding to an outlined function (i.e, a function with a code entry in the `.text` section). A function record has the following format :

```
FUNCTION BODY (one for each outlined function present in the text section)
    GUID (uint64)
        GUID of the function
    NPROBES (ULEB128)
        Number of probes originating from this function.
    NUM_INLINED_FUNCTIONS (ULEB128)
        Number of callees inlined into this function, aka number of
        first-level inlinees
    PROBE RECORDS
        A list of NPROBES entries. Each entry contains:
          INDEX (ULEB128)
          TYPE (uint4)
            0 - block probe, 1 - indirect call, 2 - direct call
          ATTRIBUTE (uint3)
            reserved
          ADDRESS_TYPE (uint1)
            0 - code address, 1 - address delta
          CODE_ADDRESS (uint64 or ULEB128)
            code address or address delta, depending on ADDRESS_TYPE
    INLINED FUNCTION RECORDS
        A list of NUM_INLINED_FUNCTIONS entries describing each of the inlined
        callees.  Each record contains:
          INLINE SITE
            GUID of the inlinee (uint64)
            ID of the callsite probe (ULEB128)
          FUNCTION BODY
            A FUNCTION BODY entry describing the inlined function.
```

To support building a context-sensitive profile, probes from inlinees are grouped by their inline contexts. An inline context is logically a call path through which a callee function lands in a caller function. The probe emitter builds an inline tree based on the debug metadata for each outlined function in the form of a trie tree. A tree root is the outlined function. Each tree edge stands for a callsite where inlining happens. Pseudo probes originating from an inlinee function are stored in a tree node and the tree path starting from the root all the way down to the tree node is the inline context of the probes. The emission happens on the whole tree top-down recursively. Probes of a tree node will be emitted altogether with their direct parent edge. Since a pseudo probe corresponds to a real code address, for size savings, the address is encoded as a delta from the previous probe except for the first probe. Variant-sized integer encoding, aka LEB128, is used for address delta and probe index.

**Assembling**

Pseudo probes can be printed as assembly directives alternatively. This allows for good assembly code readability and also provides a view of how optimizations and pseudo probes affect each other, especially helpful for diff time assembly analysis.

A pseudo probe directive has the following operands in order: function GUID, probe index, probe type, probe attributes and inline context. The directive is generated by the compiler and can be parsed by the assembler to form an encoded `.pseudoprobe` section in the object file.

A example assembly looks like:

```
foo2: # @foo2
# %bb.0: # %bb0
pushq %rax
testl %edi, %edi
.pseudoprobe 837061429793323041 1 0 0
je .LBB1_1
# %bb.2: # %bb2
.pseudoprobe 837061429793323041 6 2 0
callq foo
.pseudoprobe 837061429793323041 3 0 0
.pseudoprobe 837061429793323041 4 0 0
popq %rax
retq
.LBB1_1: # %bb1
.pseudoprobe 837061429793323041 5 1 0
callq *%rsi
.pseudoprobe 837061429793323041 2 0 0
.pseudoprobe 837061429793323041 4 0 0
popq %rax
retq
# -- End function
.section .pseudo_probe_desc,"",@progbits
.quad 6699318081062747564
.quad 72617220756
.byte 3
.ascii "foo"
.quad 837061429793323041
.quad 281547593931412
.byte 4
.ascii "foo2"
```

With inlining turned on, the assembly may look different around %bb2 with an inlined probe:

```
# %bb.2:                                # %bb2
.pseudoprobe    837061429793323041 3 0
.pseudoprobe    6699318081062747564 1 0 @ 837061429793323041:6
.pseudoprobe    837061429793323041 4 0
popq    %rax
retq
```

**Disassembling**

We have a disassembling tool (llvm-profgen) that can display disassembly alongside with pseudo probes. So far it only supports ELF executable file.

An example disassembly looks like:

```
00000000002011a0 <foo2>:
  2011a0: 50                    push   rax
  2011a1: 85 ff                 test   edi,edi
  [Probe]:  FUNC: foo2  Index: 1  Type: Block
  2011a3: 74 02                 je     2011a7 <foo2+0x7>
  [Probe]:  FUNC: foo2  Index: 3  Type: Block
  [Probe]:  FUNC: foo2  Index: 4  Type: Block
  [Probe]:  FUNC: foo   Index: 1  Type: Block  Inlined: @ foo2:6
  2011a5: 58                    pop    rax
  2011a6: c3                    ret
  [Probe]:  FUNC: foo2  Index: 2  Type: Block
  2011a7: bf 01 00 00 00        mov    edi,0x1
  [Probe]:  FUNC: foo2  Index: 5  Type: IndirectCall
  2011ac: ff d6                 call   rsi
  [Probe]:  FUNC: foo2  Index: 4  Type: Block
  2011ae: 58                    pop    rax
  2011af: c3                    ret
```

Reviewed By: wmi

Differential Revision: https://reviews.llvm.org/D91878
2020-12-10 17:29:28 -08:00
Mitch Phillips 7ead5f5aa3 Revert "[CSSPGO] Pseudo probe encoding and emission."
This reverts commit b035513c06.

Reason: Broke the ASan buildbots:
  http://lab.llvm.org:8011/#/builders/5/builds/2269
2020-12-10 15:53:39 -08:00
Mitch Phillips 9aafa9fc15 Revert "[NFC] Fix a gcc build break by not using an initializer."
This reverts commit 1dc0a8521f.

Reason: Dependency of patch that broke the ASan buildbots:
  http://lab.llvm.org:8011/#/builders/5/builds/2269
2020-12-10 15:53:38 -08:00
Hongtao Yu 1dc0a8521f [NFC] Fix a gcc build break by not using an initializer.
Test Plan:

Reviewers:

Subscribers:

Tasks:

Tags:
2020-12-10 11:54:41 -08:00
Hongtao Yu b035513c06 [CSSPGO] Pseudo probe encoding and emission.
This change implements pseudo probe encoding and emission for CSSPGO. Please see RFC here for more context: https://groups.google.com/g/llvm-dev/c/1p1rdYbL93s

Pseudo probes are in the form of intrinsic calls on IR/MIR but they do not turn into any machine instructions. Instead they are emitted into the binary as a piece of data in standalone sections.  The probe-specific sections are not needed to be loaded into memory at execution time, thus they do not incur a runtime overhead. 

**ELF object emission**

The binary data to emit are organized as two ELF sections, i.e, the `.pseudo_probe_desc` section and the `.pseudo_probe` section. The `.pseudo_probe_desc` section stores a function descriptor for each function and the `.pseudo_probe` section stores the actual probes, each fo which corresponds to an IR basic block or an IR function callsite. A function descriptor is stored as a module-level metadata during the compilation and is serialized into the object file during object emission.

Both the probe descriptors and pseudo probes can be emitted into a separate ELF section per function to leverage the linker for deduplication.  A `.pseudo_probe` section shares the same COMDAT group with the function code so that when the function is dead, the probes are dead and disposed too. On the contrary, a `.pseudo_probe_desc` section has its own COMDAT group. This is because even if a function is dead, its probes may be inlined into other functions and its descriptor is still needed by the profile generation tool.

The format of `.pseudo_probe_desc` section looks like:

```
.section   .pseudo_probe_desc,"",@progbits
.quad   6309742469962978389  // Func GUID
.quad   4294967295           // Func Hash
.byte   9                    // Length of func name
.ascii  "_Z5funcAi"          // Func name
.quad   7102633082150537521
.quad   138828622701
.byte   12
.ascii  "_Z8funcLeafi"
.quad   446061515086924981
.quad   4294967295
.byte   9
.ascii  "_Z5funcBi"
.quad   -2016976694713209516
.quad   72617220756
.byte   7
.ascii  "_Z3fibi"
```

For each `.pseudoprobe` section, the encoded binary data consists of a single function record corresponding to an outlined function (i.e, a function with a code entry in the `.text` section). A function record has the following format :

```
FUNCTION BODY (one for each outlined function present in the text section)
    GUID (uint64)
        GUID of the function
    NPROBES (ULEB128)
        Number of probes originating from this function.
    NUM_INLINED_FUNCTIONS (ULEB128)
        Number of callees inlined into this function, aka number of
        first-level inlinees
    PROBE RECORDS
        A list of NPROBES entries. Each entry contains:
          INDEX (ULEB128)
          TYPE (uint4)
            0 - block probe, 1 - indirect call, 2 - direct call
          ATTRIBUTE (uint3)
            reserved
          ADDRESS_TYPE (uint1)
            0 - code address, 1 - address delta
          CODE_ADDRESS (uint64 or ULEB128)
            code address or address delta, depending on ADDRESS_TYPE
    INLINED FUNCTION RECORDS
        A list of NUM_INLINED_FUNCTIONS entries describing each of the inlined
        callees.  Each record contains:
          INLINE SITE
            GUID of the inlinee (uint64)
            ID of the callsite probe (ULEB128)
          FUNCTION BODY
            A FUNCTION BODY entry describing the inlined function.
```

To support building a context-sensitive profile, probes from inlinees are grouped by their inline contexts. An inline context is logically a call path through which a callee function lands in a caller function. The probe emitter builds an inline tree based on the debug metadata for each outlined function in the form of a trie tree. A tree root is the outlined function. Each tree edge stands for a callsite where inlining happens. Pseudo probes originating from an inlinee function are stored in a tree node and the tree path starting from the root all the way down to the tree node is the inline context of the probes. The emission happens on the whole tree top-down recursively. Probes of a tree node will be emitted altogether with their direct parent edge. Since a pseudo probe corresponds to a real code address, for size savings, the address is encoded as a delta from the previous probe except for the first probe. Variant-sized integer encoding, aka LEB128, is used for address delta and probe index.

**Assembling**

Pseudo probes can be printed as assembly directives alternatively. This allows for good assembly code readability and also provides a view of how optimizations and pseudo probes affect each other, especially helpful for diff time assembly analysis.

A pseudo probe directive has the following operands in order: function GUID, probe index, probe type, probe attributes and inline context. The directive is generated by the compiler and can be parsed by the assembler to form an encoded `.pseudoprobe` section in the object file.

A example assembly looks like:

```
foo2: # @foo2
# %bb.0: # %bb0
pushq %rax
testl %edi, %edi
.pseudoprobe 837061429793323041 1 0 0
je .LBB1_1
# %bb.2: # %bb2
.pseudoprobe 837061429793323041 6 2 0
callq foo
.pseudoprobe 837061429793323041 3 0 0
.pseudoprobe 837061429793323041 4 0 0
popq %rax
retq
.LBB1_1: # %bb1
.pseudoprobe 837061429793323041 5 1 0
callq *%rsi
.pseudoprobe 837061429793323041 2 0 0
.pseudoprobe 837061429793323041 4 0 0
popq %rax
retq
# -- End function
.section .pseudo_probe_desc,"",@progbits
.quad 6699318081062747564
.quad 72617220756
.byte 3
.ascii "foo"
.quad 837061429793323041
.quad 281547593931412
.byte 4
.ascii "foo2"
```

With inlining turned on, the assembly may look different around %bb2 with an inlined probe:

```
# %bb.2:                                # %bb2
.pseudoprobe    837061429793323041 3 0
.pseudoprobe    6699318081062747564 1 0 @ 837061429793323041:6
.pseudoprobe    837061429793323041 4 0
popq    %rax
retq
```

**Disassembling**

We have a disassembling tool (llvm-profgen) that can display disassembly alongside with pseudo probes. So far it only supports ELF executable file.

An example disassembly looks like:

```
00000000002011a0 <foo2>:
  2011a0: 50                    push   rax
  2011a1: 85 ff                 test   edi,edi
  [Probe]:  FUNC: foo2  Index: 1  Type: Block
  2011a3: 74 02                 je     2011a7 <foo2+0x7>
  [Probe]:  FUNC: foo2  Index: 3  Type: Block
  [Probe]:  FUNC: foo2  Index: 4  Type: Block
  [Probe]:  FUNC: foo   Index: 1  Type: Block  Inlined: @ foo2:6
  2011a5: 58                    pop    rax
  2011a6: c3                    ret
  [Probe]:  FUNC: foo2  Index: 2  Type: Block
  2011a7: bf 01 00 00 00        mov    edi,0x1
  [Probe]:  FUNC: foo2  Index: 5  Type: IndirectCall
  2011ac: ff d6                 call   rsi
  [Probe]:  FUNC: foo2  Index: 4  Type: Block
  2011ae: 58                    pop    rax
  2011af: c3                    ret
```

Reviewed By: wmi

Differential Revision: https://reviews.llvm.org/D91878
2020-12-10 09:50:08 -08:00
Craig Topper a1ae3c6ac9 [RISCV][LegalizeDAG] Expand SETO and SETUO comparisons. Teach LegalizeDAG to expand SETUO expansion when UNE isn't legal.
If SETUNE isn't legal, UO can use the NOT of the SETO expansion.

Removes some complex isel patterns. Most of the test changes are
from using XORI instead of SEQZ.

Differential Revision: https://reviews.llvm.org/D92008
2020-12-10 09:15:52 -08:00
David Green 0447f3508f [ARM][RegAlloc] Add t2LoopEndDec
We currently have problems with the way that low overhead loops are
specified, with LR being spilled between the t2LoopDec and the t2LoopEnd
forcing the entire loop to be reverted late in the backend. As they will
eventually become a single instruction, this patch introduces a
t2LoopEndDec which is the combination of the two, combined before
registry allocation to make sure this does not fail.

Unfortunately this instruction is a terminator that produces a value
(and also branches - it only produces the value around the branching
edge). So this needs some adjustment to phi elimination and the register
allocator to make sure that we do not spill this LR def around the loop
(needing to put a spill after the terminator). We treat the loop very
carefully, making sure that there is nothing else like calls that would
break it's ability to use LR. For that, this adds a
isUnspillableTerminator to opt in the new behaviour.

There is a chance that this could cause problems, and so I have added an
escape option incase. But I have not seen any problems in the testing
that I've tried, and not reverting Low overhead loops is important for
our performance. If this does work then we can hopefully do the same for
t2WhileLoopStart and t2DoLoopStart instructions.

This patch also contains the code needed to convert or revert the
t2LoopEndDec in the backend (which just needs a subs; bne) and the code
pre-ra to create them.

Differential Revision: https://reviews.llvm.org/D91358
2020-12-10 12:14:23 +00:00
Luo, Yuanke f80b29878b [X86] AMX programming model.
This patch implements amx programming model that discussed in llvm-dev
 (http://lists.llvm.org/pipermail/llvm-dev/2020-August/144302.html).
 Thank Hal for the good suggestion in the RA. The fast RA is not in the patch yet.
 This patch implemeted 7 components.

1. The c interface to end user.
2. The AMX intrinsics in LLVM IR.
3. Transform load/store <256 x i32> to AMX intrinsics or split the
   type into two <128 x i32>.
4. The Lowering from AMX intrinsics to AMX pseudo instruction.
5. Insert psuedo ldtilecfg and build the def-use between ldtilecfg to amx
   intruction.
6. The register allocation for tile register.
7. Morph AMX pseudo instruction to AMX real instruction.

Change-Id: I935e1080916ffcb72af54c2c83faa8b2e97d5cb0

Differential Revision: https://reviews.llvm.org/D87981
2020-12-10 17:01:54 +08:00
Justin Bogner e6a1187dd8 Limit the recursion depth of SelectionDAG::isSplatValue()
This method previously always recursively checked both the left-hand
side and right-hand side of binary operations for splatted (broadcast)
vector values to determine if the parent DAG node is a splat.

Like several other SelectionDAG methods, limit the recursion depth to
MaxRecursionDepth (6). This prevents stack overflow.
See also https://issuetracker.google.com/173785481

Patch by Nicolas Capens. Thanks!

Differential Revision: https://reviews.llvm.org/D92421
2020-12-09 10:35:07 -08:00
Djordje Todorovic 163c223161 [Debuginfo] [CSInfo] Do not create CSInfo for undef arguments
If a function parameter is marked as "undef", prevent creation
of CallSiteInfo for that parameter.
Without this patch, the parameter's call_site_value would be incorrect.
The incorrect call_value case reported in PR39716,
addressed in D85111.
​
Patch by Nikola Tesic
​
Differential revision: https://reviews.llvm.org/D92471
2020-12-09 12:54:59 +01:00
Kerry McLaughlin 05edfc5475 [SVE][CodeGen] Add DAG combines for s/zext_masked_gather
This patch adds the following DAGCombines, which apply if isVectorLoadExtDesirable() returns true:
 - fold (and (masked_gather x)) -> (zext_masked_gather x)
 - fold (sext_inreg (masked_gather x)) -> (sext_masked_gather x)

LowerMGATHER has also been updated to fetch the LoadExtType associated with the
gather and also use this value to determine the correct masked gather opcode to use.

Reviewed By: sdesmalen

Differential Revision: https://reviews.llvm.org/D92230
2020-12-09 11:53:19 +00:00
Kerry McLaughlin 4519ff4b6f [SVE][CodeGen] Add the ExtensionType flag to MGATHER
Adds the ExtensionType flag, which reflects the LoadExtType of a MaskedGatherSDNode.
Also updated SelectionDAGDumper::print_details so that details of the gather
load (is signed, is scaled & extension type) are printed.

Reviewed By: sdesmalen

Differential Revision: https://reviews.llvm.org/D91084
2020-12-09 11:19:08 +00:00
Joe Ellis 80c33de2d3 [SelectionDAG] Add llvm.vector.{extract,insert} intrinsics
This commit adds two new intrinsics.

- llvm.experimental.vector.insert: used to insert a vector into another
  vector starting at a given index.

- llvm.experimental.vector.extract: used to extract a subvector from a
  larger vector starting from a given index.

The codegen work for these intrinsics has already been completed; this
commit is simply exposing the existing ISD nodes to LLVM IR.

Reviewed By: cameron.mcinally

Differential Revision: https://reviews.llvm.org/D91362
2020-12-09 11:08:41 +00:00
Simon Moll 3ffbc79357 [VP] Build VP SDNodes
Translate VP intrinsics to VP_* SDNodes.  The tests check whether a
matching vp_* SDNode is emitted.

Reviewed By: craig.topper

Differential Revision: https://reviews.llvm.org/D91441
2020-12-09 11:36:51 +01:00
Ilya Leoshkevich d58f112ce0 Prevent FENTRY_CALL reordering
FEntryInserter prepends FENTRY_CALL to the first basic block. In case
there are other instructions, PostRA Machine Instruction Scheduler can
move FENTRY_CALL call around. This actually occurs on SystemZ (see the
testcase). This is bad for the following reasons:

* FENTRY_CALL clobbers registers.
* Linux Kernel depends on whatever FENTRY_CALL expands to to be the very
  first instruction in the function.

Fix by adding isCall attribute to FENTRY_CALL, which prevents reordering
by making it a scheduling boundary for PostRA Machine Instruction
Scheduler.

Reviewed By: niravd

Differential Revision: https://reviews.llvm.org/D91218
2020-12-09 00:59:01 +01:00
Anna Thomas 29356e3279 [ScalarizeMaskedMemIntrin] Add new PM support
This patch adds new PM support for the pass and the pass can be now used
during middle-end transforms. The old pass is remamed to
ScalarizeMaskedMemIntrinLegacyPass.

Reviewed-By: skatkov, aeubanks
Differential Revision: https://reviews.llvm.org/D92743
2020-12-08 17:15:22 -05:00
Chih-Ping Chen 1f67247eea [DebugInfo] Add handling of stringLengthExp operand of DIStringType.
This patch makes DWARF writer emit DW_AT_string_length using
the stringLengthExp operand of DIStringType.

This is part of the effort to add debug info support for
Fortran deferred length strings.

Also updated the tests to exercise the change.

Differential Revision: https://reviews.llvm.org/D92412
2020-12-08 14:49:59 -05:00
Huihui Zhang 8e6fc1f97e [AArch64][SVE] Add lowering for llvm.maxnum|minnum for scalable type.
LLVM intrinsic llvm.maxnum|minnum is overloaded intrinsic, can be used on any
floating-point or vector of floating-point type.
This patch extends current infrastructure to support scalable vector type.

This patch also fix a warning message of incorrect use of EVT::getVectorNumElements()
for scalable type, when DAGCombiner trying to split scalable vector.

Reviewed By: sdesmalen

Differential Revision: https://reviews.llvm.org/D92607
2020-12-08 09:35:53 -08:00
Anna Thomas 09f2f9605f [ScalarizeMaskedMemIntrinsic] Move from CodeGen into Transforms
ScalarizeMaskedMemIntrinsic is currently a codeGen level pass. The pass
is actually operating on IR level and does not use any code gen specific
passes.  It is useful to move it into transforms directory so that it
can be more widely used as a mid-level transform as well (apart from
usage in codegen pipeline).
In particular, we have a usecase downstream where we would like to use
this pass in our mid-level pipeline which operates on IR level.

The next change will be to add support for new PM.

Reviewers: craig.topper, apilipenko, skatkov
Reviewed-By: skatkov
Differential Revision: https://reviews.llvm.org/D92407
2020-12-08 12:25:58 -05:00
David Sherwood e22259fafe [SVE] Remove duplicate assert in DAGTypeLegalizer::SplitVecOp_EXTRACT_SUBVECTOR 2020-12-08 14:41:14 +00:00
Pan, Tao 7af802994e [CodeGen] Add text section prefix for COFF object file
Text section prefix is created in CodeGenPrepare, it's file format independent implementation,  text section name is written into object file in TargetLoweringObjectFile, it's file format dependent implementation, port code of adding text section prefix to text section name from ELF to COFF.
Different with ELF that use '.' as concatenation character, COFF use '$' as concatenation character. That is, concatenation character is variable, so split concatenation character from text section prefix.
Text section prefix is existing feature of ELF, it can help to reduce icache and itlb misses, it's also make possible aggregate other compilers e.g. v8 created same prefix sections. Furthermore, the recent feature Machine Function Splitter (basic block level text prefix section) is based on text section prefix.

Reviewed By: pengfei, rnk

Differential Revision: https://reviews.llvm.org/D92073
2020-12-08 18:56:21 +08:00
Tim Northover c5978f42ec UBSAN: emit distinctive traps
Sometimes people get minimal crash reports after a UBSAN incident. This change
tags each trap with an integer representing the kind of failure encountered,
which can aid in tracking down the root cause of the problem.
2020-12-08 10:28:26 +00:00
Kai Luo 44bd8ea167 [DAGCombine][PowerPC] Simplify nabs by using legal `smin` operation
Convert `0 - abs(x)` to `smin (x, -x)` if `smin` is a legal operation.

Verification: https://alive2.llvm.org/ce/z/vpquFR

Reviewed By: RKSimon

Differential Revision: https://reviews.llvm.org/D92637
2020-12-08 03:24:07 +00:00
Simon Pilgrim b6e847c396 [DAG] Cleanup by folding some single use VT.getScalarSizeInBits() calls into its comparison. NFCI. 2020-12-07 18:23:54 +00:00
Kerry McLaughlin 111f559bbd [SVE][CodeGen] Call refineIndexType & refineUniformBase from visitMGATHER
The refineIndexType & refineUniformBase functions added by D90942 can also be used to
improve CodeGen of masked gathers.

These changes were split out from D91092

Reviewed By: sdesmalen

Differential Revision: https://reviews.llvm.org/D92319
2020-12-07 13:20:19 +00:00
Kerry McLaughlin f6dd32fd35 [SVE][CodeGen] Lower scalable masked gathers
Lowers the llvm.masked.gather intrinsics (scalar plus vector addressing mode only)

Changes in this patch:
- Add custom lowering for MGATHER, using getGatherVecOpcode() to choose the appropriate
  gather load opcode to use.
- Improve codegen with refineIndexType/refineUniformBase, added in D90942
- Tests added for gather loads with 32 & 64-bit scaled & unscaled offsets.

Reviewed By: sdesmalen

Differential Revision: https://reviews.llvm.org/D91092
2020-12-07 12:20:41 +00:00
Martin Storsjö 78a57069b5 [CodeGen] Restore accessing __stack_chk_guard via a .refptr stub on mingw after 2518433f86
Add tests for this particular detail for x86 and arm (similar tests
already existed for x86_64 and aarch64).

The libssp implementation may be located in a separate DLL, and in
those cases, the references need to be in a .refptr stub, to avoid
needing to touch up code in the text section at runtime (which is
supported but inefficient for x86, and unsupported for arm).

Differential Revision: https://reviews.llvm.org/D92738
2020-12-07 09:35:12 +02:00
Bing1 Yu eee30a6dce [CodeGen] Modify the refineIndexType(...)'s code to fix a bug in D90942.
In previous code, when refineIndexType(...) is called and Index is undef, Index.getOperand(0) will raise a assertion fail.

Reviewed By: pengfei

Differential Revision: https://reviews.llvm.org/D92548
2020-12-07 08:49:07 +08:00
Fangrui Song 2d03c8e2c8 [CodeGen] Delete 4 unused declarations 2020-12-06 15:02:18 -08:00
Fangrui Song 0e0d616fa2 [CodeGen] Delete 15 unused declarations
Notes about a few declarations:

* LiveVariables::RegisterDefIsDead: deleted by r47927
* createForwardControlFlowIntegrityPass, createJumpInstrTablesPass: deleted by r230780
* RegScavenger::setLiveInsUsed: deleted by r292543
* ScheduleDAGInstrs::{toggleKillFlag,startBlockForKills}: deleted by r304055
* Localizer::shouldLocalize: remnant of D75207
* DwarfDebug::addSectionLabel: deleted by r373273
2020-12-06 14:55:04 -08:00
Layton Kifer ac522f8700 [DAGCombiner] Fold (sext (not i1 x)) -> (add (zext i1 x), -1)
Move fold of (sext (not i1 x)) -> (add (zext i1 x), -1) from X86 to DAGCombiner to improve codegen on other targets.

Differential Revision: https://reviews.llvm.org/D91589
2020-12-06 11:52:10 -05:00
Kazu Hirata a553ac9791 [CodeGen] llvm::erase_if (NFC) 2020-12-05 15:44:40 -08:00
Fangrui Song 2518433f86 Make __stack_chk_guard dso_local if Reloc::Static
This is currently implied by TargetMachine::shouldAssumeDSOLocal
but will be changed in the future.
2020-12-04 16:57:45 -08:00
Simon Pilgrim 9cf4f493a7 [DAG] Move SelectionDAG implementation to KnownBits::setInReg(). NFCI. 2020-12-04 18:09:08 +00:00
Simon Pilgrim 6f4ee6f870 [DAGCombiner] Use const APInt& for getConstantOperandAPInt results. NFCI.
Avoid unnecessary instantiation.

Noticed while removing unnecessary autos
2020-12-04 09:44:58 +00:00
Arthur Eubanks 2f0de58294 [NewPM] Support --print-before/after in NPM
This changes --print-before/after to be a list of strings rather than
legacy passes. (this also has the effect of not showing the entire list
of passes in --help-hidden after --print-before/after, which IMO is
great for making it less verbose).

Currently PrintIRInstrumentation passes the class name rather than pass
name to llvm::shouldPrintBeforePass(), meaning
llvm::shouldPrintBeforePass() never functions as intended in the NPM.
There is no easy way of converting class names to pass names outside of
within an instance of PassBuilder.

This adds a map of pass class names to their short names in
PassRegistry.def within PassInstrumentationCallbacks. It is populated
inside the constructor of PassBuilder, which takes a
PassInstrumentationCallbacks.

Add a pointer to PassInstrumentationCallbacks inside
PrintIRInstrumentation and use the newly created map.

This is a bit hacky, but I can't think of a better way since the short
id to class name only exists within PassRegistry.def. This also doesn't
handle passes not in PassRegistry.def but rather added via
PassBuilder::registerPipelineParsingCallback().

llvm/test/CodeGen/Generic/print-after.ll doesn't seem very useful now
with this change.

Reviewed By: ychen, jamieschmeiser

Differential Revision: https://reviews.llvm.org/D87216
2020-12-03 16:52:14 -08:00
Anna Thomas fb2e109d45 [ScalarizeMaskedMemIntrin] NFC: Pass args by reference 2020-12-03 14:04:21 -05:00
Anna Thomas f86ec1e1fc [ScalarizeMaskedMemIntrin] NFC: Convert member functions to static
This will make it easier to add new PM support once the pass is moved
into transforms (D92407).
2020-12-03 11:46:38 -05:00
dfukalov 2ce38b3f03 [NFC] Reduce include files dependency.
1. Removed #include "...AliasAnalysis.h" in other headers and modules.
2. Cleaned up includes in AliasAnalysis.h.

Reviewed By: RKSimon

Differential Revision: https://reviews.llvm.org/D92489
2020-12-03 18:25:05 +03:00
Joe Ellis 78c0ea54a2 [DAGCombine] Fix TypeSize warning in DAGCombine::visitLIFETIME_END
Bail out early if we encounter a scalable store.

Reviewed By: peterwaller-arm

Differential Revision: https://reviews.llvm.org/D92392
2020-12-03 12:12:41 +00:00
Kazu Hirata 7a4af2a8e7 [SelectionDAG] Use is_contained (NFC) 2020-12-02 19:09:45 -08:00
Hsiangkai Wang f7bc7c2981 [RISCV] Support Zfh half-precision floating-point extension.
Support "Zfh" extension according to
https://github.com/riscv/riscv-isa-manual/blob/zfh/src/zfh.tex

Differential Revision: https://reviews.llvm.org/D90738
2020-12-03 09:16:33 +08:00
Mircea Trofin bab72dd5d5 [NFC][MC] TargetRegisterInfo::getSubReg is a MCRegister.
Typing the API appropriately.

Differential Revision: https://reviews.llvm.org/D92341
2020-12-02 15:46:38 -08:00
Hongtao Yu 24d4291ca7 [CSSPGO] Pseudo probes for function calls.
An indirect call site needs to be probed for its potential call targets. With CSSPGO a direct call also needs a probe so that a calling context can be represented by a stack of callsite probes. Unlike pseudo probes for basic blocks that are in form of standalone intrinsic call instructions, pseudo probes for callsites have to be attached to the call instruction, thus a separate instruction would not work.

One possible way of attaching a probe to a call instruction is to use a special metadata that carries information about the probe. The special metadata will have to make its way through the optimization pipeline down to object emission. This requires additional efforts to maintain the metadata in various places. Given that the `!dbg` metadata is a first-class metadata and has all essential support in place , leveraging the `!dbg` metadata as a channel to encode pseudo probe information is probably the easiest solution.

With the requirement of not inflating `!dbg` metadata that is allocated for almost every instruction, we found that the 32-bit DWARF discriminator field which mainly serves AutoFDO can be reused for pseudo probes. DWARF discriminators distinguish identical source locations between instructions and with pseudo probes such support is not required. In this change we are using the discriminator field to encode the ID and type of a callsite probe and the encoded value will be unpacked and consumed right before object emission. When a callsite is inlined, the callsite discriminator field will go with the inlined instructions. The `!dbg` metadata of an inlined instruction is in form of a scope stack. The top of the stack is the instruction's original `!dbg` metadata and the bottom of the stack is for the original callsite of the top-level inliner. Except for the top of the stack, all other elements of the stack actually refer to the nested inlined callsites whose discriminator field (which actually represents a calliste probe) can be used together to represent the inline context of an inlined PseudoProbeInst or CallInst.

To avoid collision with the baseline AutoFDO in various places that handles dwarf discriminators where a check against  the `-pseudo-probe-for-profiling` switch is not available, a special encoding scheme is used to tell apart a pseudo probe discriminator from a regular discriminator. For the regular discriminator, if all lowest 3 bits are non-zero, it means the discriminator is basically empty and all higher 29 bits can be reversed for pseudo probe use.

Callsite pseudo probes are inserted in `SampleProfileProbePass` and a target-independent MIR pass `PseudoProbeInserter` is added to unpack the probe ID/type from `!dbg`.

Note that with this work the switch -debug-info-for-profiling will not work with -pseudo-probe-for-profiling anymore. They cannot be used at the same time.

Reviewed By: wmi

Differential Revision: https://reviews.llvm.org/D91756
2020-12-02 13:45:20 -08:00
jasonliu 2c63e7604c [XCOFF][AIX] Alternative path in EHStreamer for platforms do not have uleb128 support
Summary:
Not all system assembler supports `.uleb128 label2 - label1` form.
When the target do not support this form, we have to take
alternative manual calculation to get the offsets from them.

Reviewed By: hubert.reinterpretcast

Diffierential Revision: https://reviews.llvm.org/D92058
2020-12-02 20:03:15 +00:00
Nick Desaulniers bc044a88ee [Inline] prevent inlining on stack protector mismatch
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

SSP attributes can be ordered by strength. Weakest to strongest, they
are: ssp, sspstrong, sspreq.  Callees with differing SSP attributes may be
inlined into each other, and the strongest attribute will be applied to the
caller. (No change)

After this change:
* A callee with no SSP attributes will no longer be inlined into a
  caller with SSP attributes.
* The reverse is also true: a callee with an SSP attribute will not be
  inlined into a caller with no SSP attributes.
* The alwaysinline attribute overrides these rules.

Functions that get synthesized by the compiler may not get inlined as a
result if they are not created with the same stack protector function
attribute as their callers.

Alternative approach to https://reviews.llvm.org/D87956.

Fixes pr/47479.

Signed-off-by: Nick Desaulniers <ndesaulniers@google.com>

Reviewed By: rnk, MaskRay

Differential Revision: https://reviews.llvm.org/D91816
2020-12-02 11:00:16 -08:00
jasonliu a65d8c5d72 [XCOFF][AIX] Generate LSDA data and compact unwind section on AIX
Summary:
AIX uses the existing EH infrastructure in clang and llvm.
The major differences would be
1. AIX do not have CFI instructions.
2. AIX uses a new personality routine, named __xlcxx_personality_v1.
   It doesn't use the GCC personality rountine, because the
   interoperability is not there yet on AIX.
3. AIX do not use eh_frame sections. Instead, it would use a eh_info
section (compat unwind section) to store the information about
personality routine and LSDA data address.

Reviewed By: daltenty, hubert.reinterpretcast

Differential Revision: https://reviews.llvm.org/D91455
2020-12-02 18:42:44 +00:00
James Park 78b0ec3d1c Avoid redundant inline with LLVM_ATTRIBUTE_ALWAYS_INLINE
Fix MSVC warning when __forceinline is paired with inline.

Reviewed By: dblaikie

Differential Revision: https://reviews.llvm.org/D85264
2020-12-01 14:43:16 -08:00
David Blaikie 615f63e149 Revert "[FastISel] Flush local value map on ever instruction" and dependent patches
This reverts commit cf1c774d6a.

This change caused several regressions in the gdb test suite - at least
a sample of which was due to line zero instructions making breakpoints
un-lined. I think they're worth investigating/understanding more (&
possibly addressing) before moving forward with this change.

Revert "[FastISel] NFC: Clean up unnecessary bookkeeping"
This reverts commit 3fd39d3694.

Revert "[FastISel] NFC: Remove obsolete -fast-isel-sink-local-values option"
This reverts commit a474657e30.

Revert "Remove static function unused after cf1c774."
This reverts commit dc35368ccf.

Revert "[lldb] Fix TestThreadStepOut.py after "Flush local value map on every instruction""
This reverts commit 53a14a47ee.
2020-12-01 14:26:23 -08:00
Layton Kifer d7fec38f05
[DAGCombiner][NFC] Replace duplicate implementation flipBoolean with DAG.getLogicalNOT
Reviewed By: lebedev.ri

Differential Revision: https://reviews.llvm.org/D92246
2020-12-01 22:23:04 +03:00
Fangrui Song a5309438fe static const char *const foo => const char foo[]
By default, a non-template variable of non-volatile const-qualified type
having namespace-scope has internal linkage, so no need for `static`.
2020-12-01 10:33:18 -08:00
Benjamin Kramer 107e92dff8 [DAG] Remove unused variable. NFC. 2020-12-01 16:29:02 +01:00
Simon Pilgrim 1b209ff9e3 [DAG] Move vselect(icmp_ult, 0, sub(x,y)) -> usubsat(x,y) to DAGCombine (PR40111)
Move the X86 VSELECT->USUBSAT fold to DAGCombiner - there's nothing target specific about these folds.
2020-12-01 14:25:29 +00:00
Simon Pilgrim 6dbd0d36a1 [DAG] Move vselect(icmp_ult, -1, add(x,y)) -> uaddsat(x,y) to DAGCombine (PR40111)
Move the X86 VSELECT->UADDSAT fold to DAGCombiner - there's nothing target specific about these folds.

The SSE42 test diffs are relatively benign - its avoiding an extra constant load in exchange for an extra xor operation - there are extra register moves, which is annoying as all those operations should commute them away.

Differential Revision: https://reviews.llvm.org/D91876
2020-12-01 11:56:26 +00:00
Kazu Hirata e785379aff [CodeView] Remove unused declaration collectInlineSiteChildren (NFC)
The function definition was removed on Sep 7, 2016 in commit
a9f4cc9510.  The declaration seems to be
unused since then.
2020-11-30 22:28:26 -08:00
Hendrik Greving d4ba5e15f4 Add MachineModuleInfo constructor with external MCContext
Adds a constructor to MachineModuleInfo and MachineModuleInfoWapperPass that
takes an external MCContext. If provided, the external context will be used
throughout codegen instead of MMI's default one.

This enables external drivers to take ownership of data put on the MMI's context
during codegen. The internal context is used otherwise and destroyed upon
finish.

Differential Revision: https://reviews.llvm.org/D91313
2020-11-30 20:28:13 -08:00
Fangrui Song d928dfc6f9 [GlobalISel] Fix -Wunused-variable in -DLLVM_ENABLE_ASSERTIONS=off builds 2020-11-30 18:31:42 -08:00
Fangrui Song 36fe1a9dea [GlobalISel] Fix -Wunused-variable 2020-11-30 18:25:54 -08:00
Amara Emerson 87ff156414 [AArch64][GlobalISel] Fix crash during legalization of a vector G_SELECT with scalar mask.
The lowering of vector selects needs to first splat the scalar mask into a vector
first.

This was causing a crash when building oggenc in the test suite.

Differential Revision: https://reviews.llvm.org/D91655
2020-11-30 16:37:49 -08:00
Paul Robinson 3fd39d3694 [FastISel] NFC: Clean up unnecessary bookkeeping
Now that we flush the local value map for every instruction, we don't
need any extra flushes for specific cases.  Also, LastFlushPoint is
not used for anything.  Follow-ups to #dc35368 (D91734).

Differential Revision: https://reviews.llvm.org/D92338
2020-11-30 12:27:50 -08:00
Matt Arsenault 29bd6519d2 SplitKit: Use Register 2020-11-30 15:09:33 -05:00
Paul Robinson a474657e30 [FastISel] NFC: Remove obsolete -fast-isel-sink-local-values option
This option is not used for anything after #dc35368 (D91734).
2020-11-30 10:55:49 -08:00
Francesco Petrogalli f6150aa41a [SelectionDAGBuilder] Update signature of `getRegsAndSizes()`.
The mapping between registers and relative size has been updated to
use TypeSize to account for the size of scalable EVTs.

The patch is a NFCI, if not for the fact that with this change the
function `getUnderlyingArgRegs` does not raise a warning for implicit
conversion of `TypeSize` to `unsigned` when generating machine code
from the test added to the patch.

Reviewed By: arsenm

Differential Revision: https://reviews.llvm.org/D92096
2020-11-30 17:38:51 +00:00
Craig Topper fa0f01a3c0 [RISCV][LegalizeTypes] Teach type legalizer that it can promote UMIN/UMAX using SExtPromotedInteger if that's better for the target.
If Sext is cheaper than Zext for a target, we can use that to promote the operands of UMIN/UMAX. Using sext just makes numbers with the sign bit set even larger when treated as an unsigned number and it has no effect on number without the sign bit set. So the relative order doesn't change. This is similar to what we already do for promoting SETCC.

This is helpful on RISCV where i32 arguments are sign extended on RV64 and many instructions are able to produce results with 33 sign bits.

Differential Revision: https://reviews.llvm.org/D92128
2020-11-27 11:37:25 -08:00
Simon Pilgrim 969918e177 [DAG] Legalize umin(x,y) -> sub(x,usubsat(x,y)) and umax(x,y) -> add(x,usubsat(y,x)) iff usubsat is legal
If usubsat() is legal, this is likely to result in smaller codegen expansion than the default cmp+select codegen expansion.

Allows us to move the x86-specific lowering to the generic expansion code.

Differential Revision: https://reviews.llvm.org/D92183
2020-11-27 11:18:58 +00:00
QingShan Zhang 4d83aba422 [DAGCombine] Adding a hook to improve the precision of fsqrt if the input is denormal
For now, we will hardcode the result as 0.0 if the input is denormal or 0. That will
have the impact the precision. As the fsqrt added belong to the cold path of the
cmp+branch, it won't impact the performance for normal inputs for PowerPC, but improve
the precision if the input is denormal.

Reviewed By: Spatel

Differential Revision: https://reviews.llvm.org/D80974
2020-11-27 02:10:55 +00:00
Nikita Popov 4df8efce80 [AA] Split up LocationSize::unknown()
Currently, we have some confusion in the codebase regarding the
meaning of LocationSize::unknown(): Some parts (including most of
BasicAA) assume that LocationSize::unknown() only allows accesses
after the base pointer. Some parts (various callers of AA) assume
that LocationSize::unknown() allows accesses both before and after
the base pointer (but within the underlying object).

This patch splits up LocationSize::unknown() into
LocationSize::afterPointer() and LocationSize::beforeOrAfterPointer()
to make this completely unambiguous. I tried my best to determine
which one is appropriate for all the existing uses.

The test changes in cs-cs.ll in particular illustrate a previously
clearly incorrect AA result: We were effectively assuming that
argmemonly functions were only allowed to access their arguments
after the passed pointer, but not before it. I'm pretty sure that
this was not intentional, and it's certainly not specified by
LangRef that way.

Differential Revision: https://reviews.llvm.org/D91649
2020-11-26 18:39:55 +01:00
Simon Pilgrim 8057ebf4a0 Revert rG12d59b696b330 "[DAG] Legalize umin(x,y) -> sub(x,usubsat(x,y)) and umax(x,y) -> add(x,usubsat(y,x)) iff usubsat is legal"
This reverts commit 12d59b696b.

Prematurely pushed this to trunk
2020-11-26 15:07:45 +00:00
Simon Pilgrim 12d59b696b [DAG] Legalize umin(x,y) -> sub(x,usubsat(x,y)) and umax(x,y) -> add(x,usubsat(y,x)) iff usubsat is legal
If usubsat() is legal, this is likely to result in smaller codegen expansion than the default cmp+select codegen expansion.

Allows us to move the x86-specific lowering to the generic expansion code.
2020-11-26 14:47:28 +00:00
Robert Lougher 6464c4a170 [LiveDebugVariables] Strip all debug instructions from nodebug functions
A crash/assertion failure in the greedy register allocator was tracked
down to a debug instr being passed to LiveIntervals::getInstructionIndex.
Normally this should not occur as debug instructions are collected and
removed by LiveDebugVariables before RA, and reinserted afterwards.
However, when a function has no debug info, LiveDebugVariables simply
strips any debug values that are present as they're not needed (this
situation will occur when a function with debug info is inlined into a
nodebug function). The problem is, it only removes DBG_VALUE instructions,
leaving DBG_LABELs (the cause of the crash).

This patch updates the LiveDebugVariables nodebug path to remove all debug
instructions. The test case verifies that DBG_VALUE/DBG_LABEL instructions
are present, and that they are stripped.

When -experimental-debug-variable-locations is enabled, certain variable
locations are represented by DBG_INSTR_REF instead of DBG_VALUE. The test
case verifies that a DBG_INSTR_REF is emitted by the option, and that it
is also stripped.

Differential Revision: https://reviews.llvm.org/D92127
2020-11-26 14:30:18 +00:00
Kerry McLaughlin 4bee3197f6 [SVE][CodeGen] Extend isConstantSplatValue to support ISD::SPLAT_VECTOR
Updated the affected scalable_of_scalable tests in sve-gep.ll, as isConstantSplatValue now returns true in DAGCombiner::visitMUL and folds `(mul x, 1) -> x`

Reviewed By: sdesmalen

Differential Revision: https://reviews.llvm.org/D91363
2020-11-26 11:19:40 +00:00
Craig Topper aea130f736 [LegalizerTypes] Add support for scalarizing the operand of an FP_EXTEND when the result type is legal. 2020-11-25 20:30:21 -08:00
Amy Huang 1363dfaf31 [CodeView] Avoid emitting empty debug globals subsection.
In https://reviews.llvm.org/D89072 I added static const data members
to the debug subsection for globals. It skipped emitting an S_CONSTANT if it
didn't have a value, which meant the subsection could be empty.

This patch fixes the empty subsection issue.

Differential Revision: https://reviews.llvm.org/D92049
2020-11-25 16:13:32 -08:00
Craig Topper 2d6042937b [SelectionDAGBuilder] Add SPF_NABS support to visitSelect
We currently don't match this which limits the effectiveness of D91120 until
InstCombine starts canonicalizing to llvm.abs. This should be easy to remove
if/when we remove the SPF_ABS handling.

Differential Revision: https://reviews.llvm.org/D92118
2020-11-25 14:54:26 -08:00
Paul Robinson dc35368ccf Remove static function unused after cf1c774.
Caused some -Werror bot failures.
2020-11-25 13:43:06 -05:00
Simon Pilgrim 9c86c5e8ad [DAG] Legalize abs(x) -> umin(x,sub(0,x)) iff umin/sub are legal
If umin() is legal, this is likely to result in smaller codegen expansion for abs(x) than the xor(add,ashr) method.

Followup to D92095

Alive2: https://alive2.llvm.org/ce/z/8nuX6s  https://alive2.llvm.org/ce/z/q2hB9w
2020-11-25 18:06:02 +00:00
Paul Robinson cf1c774d6a [FastISel] Flush local value map on ever instruction
Local values are constants or addresses that can't be folded into
the instruction that uses them. FastISel materializes these in a
"local value" area that always dominates the current insertion
point, to try to avoid materializing these values more than once
(per block).

https://reviews.llvm.org/D43093 added code to sink these local
value instructions to their first use, which has two beneficial
effects. One, it is likely to avoid some unnecessary spills and
reloads; two, it allows us to attach the debug location of the
user to the local value instruction. The latter effect can
improve the debugging experience for debuggers with a "set next
statement" feature, such as the Visual Studio debugger and PS4
debugger, because instructions to set up constants for a given
statement will be associated with the appropriate source line.

There are also some constants (primarily addresses) that could be
produced by no-op casts or GEP instructions; the main difference
from "local value" instructions is that these are values from
separate IR instructions, and therefore could have multiple users
across multiple basic blocks. D43093 avoided sinking these, even
though they were emitted to the same "local value" area as the
other instructions. The patch comment for D43093 states:

  Local values may also be used by no-op casts, which adds the
  register to the RegFixups table. Without reversing the RegFixups
  map direction, we don't have enough information to sink these
  instructions.

This patch undoes most of D43093, and instead flushes the local
value map after(*) every IR instruction, using that instruction's
debug location. This avoids sometimes incorrect locations used
previously, and emits instructions in a more natural order.

This does mean materialized values are not re-used across IR
instruction boundaries; however, only about 5% of those values
were reused in an experimental self-build of clang.

(*) Actually, just prior to the next instruction. It seems like
it would be cleaner the other way, but I was having trouble
getting that to work.

Differential Revision: https://reviews.llvm.org/D91734
2020-11-25 13:05:00 -05:00
Simon Pilgrim 0637dfe88b [DAG] Legalize abs(x) -> smax(x,sub(0,x)) iff smax/sub are legal
If smax() is legal, this is likely to result in smaller codegen expansion for abs(x) than the xor(add,ashr) method.

This is also what PowerPC has been doing for its abs implementation, so it lets us get rid of a load of custom lowering code there (and which was never updated when they added smax lowering).

Alive2: https://alive2.llvm.org/ce/z/xRk3cD

Differential Revision: https://reviews.llvm.org/D92095
2020-11-25 15:03:03 +00:00
Simon Pilgrim 7e7106d104 DetectDeadLanes.cpp - remove unused headers. NFCI. 2020-11-25 11:38:28 +00:00
QingShan Zhang 9c588f53fc [DAGCombine] Add hook to allow target specific test for sqrt input
PowerPC has instruction ftsqrt/xstsqrtdp etc to do the input test for software square root.
LLVM now tests it with smallest normalized value using abs + setcc. We should add hook to
target that has test instructions.

Reviewed By: Spatel, Chen Zheng, Qiu Chao Fang

Differential Revision: https://reviews.llvm.org/D80706
2020-11-25 05:37:15 +00:00
Kai Luo 8e6d92026c [DAG][PowerPC] Fix dropped `nsw` flag in `SimplifySetCC` by adding `doesNodeExist` helper
`SimplifySetCC` invokes `getNodeIfExists` without passing `Flags` argument and `getNodeIfExists` uses a default `SDNodeFlags` to intersect the original flags, as a consequence, flags like `nsw` is dropped. Added a new helper function `doesNodeExist` to check if a node exists without modifying its flags.

Reviewed By: #powerpc, nemanjai

Differential Revision: https://reviews.llvm.org/D89938
2020-11-25 04:39:03 +00:00
Zarko Todorovski c92f29b05e [AIX] Add mabi=vec-extabi options to enable the AIX extended and default vector ABIs.
Added support for the options mabi=vec-extabi and mabi=vec-default which are analogous to qvecnvol and qnovecnvol when using XL on AIX.
The extended Altivec ABI on AIX is enabled using mabi=vec-extabi in clang and vec-extabi in llc.

Reviewed By: Xiangling_L, DiggerLin

Differential Revision: https://reviews.llvm.org/D89684
2020-11-24 18:17:53 -05:00
Hsiangkai Wang 8d06a678a5 [SelectionDAG] Avoid aliasing analysis if the object size is unknown.
If the size of memory access is unknown, do not use it to analysis. One
example of unknown size memory access is to load/store scalable vector
objects on the stack.

Differential Revision: https://reviews.llvm.org/D91833
2020-11-25 06:13:37 +08:00
Janek van Oirschot 42eaf4fe0a [HardwareLoops] Change order of SCEV expression construction for InitLoopCount.
Putting the +1 before the zero-extend will allow scalar evolution to fold the expression in some cases such as the one shown in PowerPC's `shrink-wrap.ll` test.

Reviewed By: samparker

Differential Revision: https://reviews.llvm.org/D91724
2020-11-24 18:01:42 +00:00
Yichao Yu a248eca665
Clear NewGEPBases after finish using them in CodeGenPrep pass
AFAICT all other set/map are correctly cleared in `runOnFunction`.

With assertion enabled this causes a crash when the module is freed and potentially if a later pass delete the instruction (not observed in real world though). Without assertion this can potentially cause confusing result when running on a new Function/Module.

Reviewed By: loladiro

Differential Revision: https://reviews.llvm.org/D84031
2020-11-24 12:12:00 -05:00
Thomas Preud'homme 9c8af93c93 Add support for STRICT_FSETCC promotion
Add missing handling of STRICT_FSETCC promotion. This prevents assert
failure in llvm::TargetLoweringBase::getTypeToPromoteTo().

Reviewed By: uweigand

Differential Revision: https://reviews.llvm.org/D91962
2020-11-24 16:53:49 +00:00
Kai Luo 5931be60b5 [DAGCombine][PowerPC] Convert negated abs to trivial arithmetic ops
This patch converts `0 - abs(x)` to `Y = sra (X, size(X)-1); sub (Y, xor (X, Y))` for better codegen.

Reviewed By: RKSimon

Differential Revision: https://reviews.llvm.org/D91120
2020-11-24 09:43:35 +00:00
Pavel Labath bce2ac9f6d Revert "[DebugInfo] Refactor code for emitting DWARF expressions for FP constants"
The commit introduced a crash when emitting (debug info for) complex
floats (pr48277).
2020-11-24 09:11:33 +01:00
Martin Storsjö 6f792041a5 Reapply "[CodeGen] [WinException] Only produce handler data at the end of the function if needed"
This reapplies 36c64af9d7 in updated
form.

Emit the xdata for each function at .seh_endproc. This keeps the
exact same output header order for most code generated by the LLVM
CodeGen layer. (Sections still change order for code built from
assembly where functions lack an explicit .seh_handlerdata
directive, and functions with chained unwind info.)

The practical effect should be that assembly output lacks
superfluous ".seh_handlerdata; .text" pairs at the end of functions
that don't handle exceptions, which allows such functions to use
the AArch64 packed unwind format again.

Differential Revision: https://reviews.llvm.org/D87448
2020-11-23 23:17:03 +02:00
Pavel Labath 6ef7835afc [DebugInfo] Refactor code for emitting DWARF expressions for FP constants
This patch moves the selection of the style used to emit the numbers
(DW_OP_implicit_value vs. DW_OP_const+DW_OP_stack_value) into
DwarfExpression::addUnsignedConstant. This logic is not FP-specific, and
it will be needed for large integers too.

The refactor also makes DW_OP_implicit_value (DW_OP_stack_value worked
already) be used for floating point constants other than float and
double, so I've added a _Float16 test for it.

Split off from D90916.

Differential Revision: https://reviews.llvm.org/D91058
2020-11-23 09:59:07 +01:00
Kazu Hirata 85d6af393c [CodeGen] Use pred_empty (NFC) 2020-11-22 22:16:13 -08:00
Simon Pilgrim 791040cd8b [DAG] LowerMINMAX - move default expansion to generic TargetLowering::expandIntMINMAX
This is part of the discussion on D91876 about trying to reduce custom lowering of MIN/MAX ops on older SSE targets - if we can improve generic vector expansion we should be able to relax the limitations in SelectionDAGBuilder when it will let MIN/MAX ops be generated, and avoid having to flag so many ops as 'custom'.
2020-11-22 13:02:27 +00:00
Kazu Hirata 68403af007 [MBP] Remove unused declaration shouldPredBlockBeOutlined (NFC)
The function was introduced on Jun 12, 2016 in commit
071d0f1807.  Its definition was removed
on Mar 2, 2017 in commit 1393761e0c.
2020-11-21 23:35:02 -08:00
Kazu Hirata 9d985082ad [MachineLICM] Remove unused declaration HoistRegion
The function definition was removed on Dec 22, 2011 in commit
in 1eed5b51e8.
2020-11-21 22:55:37 -08:00
Kazu Hirata c2309ff3d5 [SelectionDAG] Remove unused declaration ExpandStrictFPOp (NFC)
ExpandStrictFPOp started taking two parameters instead of one on Jan
10, 2020 in commit f678fc7660, but the
declaration for the single-perameter version has remained since.
2020-11-21 22:29:44 -08:00
Ella Ma 1756d67934 [llvm][clang][mlir] Add checks for the return values from Target::createXXX to prevent protential null deref
All these potential null pointer dereferences are reported by my static analyzer for null smart pointer dereferences, which has a different implementation from `alpha.cplusplus.SmartPtr`.

The checked pointers in this patch are initialized by Target::createXXX functions. When the creator function pointer is not correctly set, a null pointer will be returned, or the creator function may originally return a null pointer.

Some of them may not make sense as they may be checked before entering the function, but I fixed them all in this patch. I submit this fix because 1) similar checks are found in some other places in the LLVM codebase for the same return value of the function; and, 2) some of the pointers are dereferenced before they are checked, which may definitely trigger a null pointer dereference if the return value is nullptr.

Reviewed By: tejohnson, MaskRay, jpienaar

Differential Revision: https://reviews.llvm.org/D91410
2020-11-21 21:04:12 -08:00
Hongtao Yu d0e42037bf [CSSPGO] MIR target-independent pseudo instruction for pseudo-probe intrinsic
This change introduces a MIR target-independent pseudo instruction corresponding to the IR intrinsic llvm.pseudoprobe for pseudo-probe block instrumentation. Please refer to https://reviews.llvm.org/D86193 for the whole story.

An `llvm.pseudoprobe` intrinsic call will be lowered into a target-independent operation named `PSEUDO_PROBE`. Given the following instrumented IR,

```
define internal void @foo2(i32 %x, void (i32)* %f) !dbg !4 {
bb0:
   %cmp = icmp eq i32 %x, 0
   call void @llvm.pseudoprobe(i64 837061429793323041, i64 1)
   br i1 %cmp, label %bb1, label %bb2
bb1:
   call void @llvm.pseudoprobe(i64 837061429793323041, i64 2)
   br label %bb3
bb2:
   call void @llvm.pseudoprobe(i64 837061429793323041, i64 3)
   br label %bb3
bb3:
   call void @llvm.pseudoprobe(i64 837061429793323041, i64 4)
   ret void
}
```
the corresponding MIR is shown below. Note that block `bb3` is duplicated into `bb1` and `bb2` where its probe is duplicated too. This allows for an accurate execution count to be collected for `bb3`, which is basically the sum of the counts of `bb1` and `bb2`.

```
bb.0.bb0:
   frame-setup PUSH64r undef $rax, implicit-def $rsp, implicit $rsp
   TEST32rr killed renamable $edi, renamable $edi, implicit-def $eflags
   PSEUDO_PROBE 837061429793323041, 1, 0
   $edi = MOV32ri 1, debug-location !13; test.c:0
   JCC_1 %bb.1, 4, implicit $eflags

bb.2.bb2:
   PSEUDO_PROBE 837061429793323041, 3, 0
   PSEUDO_PROBE 837061429793323041, 4, 0
   $rax = frame-destroy POP64r implicit-def $rsp, implicit $rsp
   RETQ

bb.1.bb1:
   PSEUDO_PROBE 837061429793323041, 2, 0
   PSEUDO_PROBE 837061429793323041, 4, 0
   $rax = frame-destroy POP64r implicit-def $rsp, implicit $rsp
   RETQ
```

The target op PSEUDO_PROBE will be converted into a piece of binary data by the object emitter with no machine instructions generated. This is done in a different patch.

Reviewed By: wmi

Differential Revision: https://reviews.llvm.org/D86495
2020-11-20 10:52:43 -08:00
Hongtao Yu f3c445697d [CSSPGO] IR intrinsic for pseudo-probe block instrumentation
This change introduces a new IR intrinsic named `llvm.pseudoprobe` for pseudo-probe block instrumentation. Please refer to https://reviews.llvm.org/D86193 for the whole story.

A pseudo probe is used to collect the execution count of the block where the probe is instrumented. This requires a pseudo probe to be persisting. The LLVM PGO instrumentation also instruments in similar places by placing a counter in the form of atomic read/write operations or runtime helper calls. While these operations are very persisting or optimization-resilient, in theory we can borrow the atomic read/write implementation from PGO counters and cut it off at the end of compilation with all the atomics converted into binary data. This was our initial design and we’ve seen promising sample correlation quality with it. However, the atomics approach has a couple issues:

1. IR Optimizations are blocked unexpectedly. Those atomic instructions are not going to be physically present in the binary code, but since they are on the IR till very end of compilation, they can still prevent certain IR optimizations and result in lower code quality.
2. The counter atomics may not be fully cleaned up from the code stream eventually.
3. Extra work is needed for re-targeting.

We choose to implement pseudo probes based on a special LLVM intrinsic, which is expected to have most of the semantics that comes with an atomic operation but does not block desired optimizations as much as possible. More specifically the semantics associated with the new intrinsic enforces a pseudo probe to be virtually executed exactly the same number of times before and after an IR optimization. The intrinsic also comes with certain flags that are carefully chosen so that the places they are probing are not going to be messed up by the optimizer while most of the IR optimizations still work. The core flags given to the special intrinsic is `IntrInaccessibleMemOnly`, which means the intrinsic accesses memory and does have a side effect so that it is not removable, but is does not access memory locations that are accessible by any original instructions. This way the intrinsic does not alias with any original instruction and thus it does not block optimizations as much as an atomic operation does. We also assign a function GUID and a block index to an intrinsic so that they are uniquely identified and not merged in order to achieve good correlation quality.

Let's now look at an example. Given the following LLVM IR:

```
define internal void @foo2(i32 %x, void (i32)* %f) !dbg !4 {
bb0:
  %cmp = icmp eq i32 %x, 0
   br i1 %cmp, label %bb1, label %bb2
bb1:
   br label %bb3
bb2:
   br label %bb3
bb3:
   ret void
}
```

The instrumented IR will look like below. Note that each `llvm.pseudoprobe` intrinsic call represents a pseudo probe at a block, of which the first parameter is the GUID of the probe’s owner function and the second parameter is the probe’s ID.

```
define internal void @foo2(i32 %x, void (i32)* %f) !dbg !4 {
bb0:
   %cmp = icmp eq i32 %x, 0
   call void @llvm.pseudoprobe(i64 837061429793323041, i64 1)
   br i1 %cmp, label %bb1, label %bb2
bb1:
   call void @llvm.pseudoprobe(i64 837061429793323041, i64 2)
   br label %bb3
bb2:
   call void @llvm.pseudoprobe(i64 837061429793323041, i64 3)
   br label %bb3
bb3:
   call void @llvm.pseudoprobe(i64 837061429793323041, i64 4)
   ret void
}

```

Reviewed By: wmi

Differential Revision: https://reviews.llvm.org/D86490
2020-11-20 10:39:24 -08:00
Craig Topper a7eae62a42 [SelectionDAG][X86][PowerPC][Mips] Replace the default implementation of LowerOperationWrapper with the X86 and PowerPC version.
The default version only works if the returned node has a single
result. The X86 and PowerPC versions support multiple results
and allow a single result to be returned from a node with
multiple outputs. And allow a single result that is not result 0
of the node.

Also replace the Mips version since the new version should work
for it. The original version handled multiple results, but only
if the new node and original node had the same number of results.

Differential Revision: https://reviews.llvm.org/D91846
2020-11-20 10:06:53 -08:00
Andrew Wei 1cd19fc568 [DeadMachineInstrctionElim] Post order visit all blocks and Iteratively run DeadMachineInstructionElim pass until nothing dead
Patched by: guopeilin
Reviewed By: hliao,rampitec

Differential Revision: https://reviews.llvm.org/D91513
2020-11-21 00:43:23 +08:00
Pavel Iliin 4d7df43ffd [AArch64] Out-of-line atomics (-moutline-atomics) implementation.
This patch implements out of line atomics for LSE deployment
mechanism. Details how it works can be found in llvm/docs/Atomics.rst
Options -moutline-atomics and -mno-outline-atomics to enable and disable it
were added to clang driver. This is clang and llvm part of out-of-line atomics
interface, library part is already supported by libgcc. Compiler-rt
support is provided in separate patch.

Differential Revision: https://reviews.llvm.org/D91157
2020-11-20 13:30:12 +00:00
Kazu Hirata 2583d8eb08 [CodeGen] Use llvm::is_contained (NFC) 2020-11-19 22:07:56 -08:00
Nikita Popov 393b9e9db3 [MemLoc] Require LocationSize argument (NFC)
When constructing a MemoryLocation by hand, require that a
LocationSize is explicitly specified. D91649 will split up
LocationSize::unknown() into two different states, and callers
should make an explicit choice regarding the kind of MemoryLocation
they want to have.
2020-11-19 21:45:52 +01:00
Leonard Chan a97f62837f [llvm][IR] Add dso_local_equivalent Constant
The `dso_local_equivalent` constant is a wrapper for functions that represents a
value which is functionally equivalent to the global passed to this. That is, if
this accepts a function, calling this constant should have the same effects as
calling the function directly. This could be a direct reference to the function,
the `@plt` modifier on X86/AArch64, a thunk, or anything that's equivalent to the
resolved function as a call target.

When lowered, the returned address must have a constant offset at link time from
some other symbol defined within the same binary. The address of this value is
also insignificant. The name is leveraged from `dso_local` where use of a function
or variable is resolved to a symbol in the same linkage unit.

In this patch:
- Addition of `dso_local_equivalent` and handling it
- Update Constant::needsRelocation() to strip constant inbound GEPs and take
  advantage of `dso_local_equivalent` for relative references

This is useful for the [Relative VTables C++ ABI](https://reviews.llvm.org/D72959)
which makes vtables readonly. This works by replacing the dynamic relocations for
function pointers in them with static relocations that represent the offset between
the vtable and virtual functions. If a function is externally defined,
`dso_local_equivalent` can be used as a generic wrapper for the function to still
allow for this static offset calculation to be done.

See [RFC](http://lists.llvm.org/pipermail/llvm-dev/2020-August/144469.html) for more details.

Differential Revision: https://reviews.llvm.org/D77248
2020-11-19 10:26:17 -08:00
Adhemerval Zanella 807320119f [AArch64] Lower fptrunc/fpext from/to FP128t to/from FP16
The compiler-rt part which adds the emitted symbols is handled in
a subsequent patch.

Differential Revision: https://reviews.llvm.org/D91731
2020-11-19 15:14:50 -03:00
Florian Hahn 1983acce7c
[SelDAGBuilder] Do not require simple VTs for constraints.
In some cases, the values passed to `asm sideeffect` calls cannot be
mapped directly to simple MVTs. Currently, we crash in the backend if
that happens. An example can be found in the @test_vector_too_large_r_m
test case, where we pass <9 x float> vectors. In practice, this can
happen in cases like the simple C example below.

using vec = float __attribute__((ext_vector_type(9)));
void f1 (vec m) {
  asm volatile("" : "+r,m"(m) : : "memory");
}

One case that use "+r,m" constraints for arbitrary data types in
practice is google-benchmark's DoNotOptimize.

This patch updates visitInlineAsm so that it use MVT::Other for
constraints with complex VTs. It looks like the rest of the backend
correctly deals with that and properly legalizes the type.

And we still report an error if there are no registers to satisfy the
constraint.

Reviewed By: arsenm

Differential Revision: https://reviews.llvm.org/D91710
2020-11-19 09:31:54 +00:00
Andrew Paverd 0139c8af8d [CFGuard] Add address-taken IAT tables and delay-load support
This patch adds support for creating Guard Address-Taken IAT Entry Tables (.giats$y sections) in object files, matching the behavior of MSVC. These contain lists of address-taken imported functions, which are used by the linker to create the final GIATS table.
Additionally, if any DLLs are delay-loaded, the linker must look through the .giats tables and add the respective load thunks of address-taken imports to the GFIDS table, as these are also valid call targets.

Reviewed By: rnk

Differential Revision: https://reviews.llvm.org/D87544
2020-11-17 18:24:45 -08:00
Nick Desaulniers f4c6080ab8 Revert "[IR] add fn attr for no_stack_protector; prevent inlining on mismatch"
This reverts commit b7926ce6d7.

Going with a simpler approach.
2020-11-17 17:27:14 -08:00
Jon Roelofs a461e76b6f [MachineScheduler] Inform pass infra of post-ra scheduler's dependencies
Differential Revision: https://reviews.llvm.org/D91561
2020-11-17 10:56:12 -08:00
Florian Hahn a9adb62a64
[AsmPrinter] Use getMnemonic for instruction-mix remark.
This patch uses the new `getMnemonic` helper from D90039
to display mnemonics instead of the internal opcodes.

The main motivation behind using the mnemonics is that they
are more user-friendly and more directly related to the assembly
the users will be presented.

Reviewed By: paquette

Differential Revision: https://reviews.llvm.org/D90040
2020-11-17 12:12:47 +00:00
Jameson Nash bf6ed355c8 Reland "[AsmPrinter] fix -disable-debug-info option"
This reverts commit 105ed27ed8, and
removes the offending line from the tests.
2020-11-16 13:34:47 -05:00
Mirko Brkusanin 4cf6dd518e [AMDGPU][GlobalISel] Fix lowerShlSat
RegBankSelect would crash on G_SELECT when type is not s1.

Differential Revision: https://reviews.llvm.org/D91437
2020-11-16 17:43:31 +01:00
Victor Huang 6bb2ceac90 Fix the compilation assertion due to unreachable BB pruning not deleting the associated BB from the jump tables
This patch is added to remove the unreachable MBBs reference in the jump table.

Differential Revisien: https://reviews.llvm.org/D90498
Reviewed by: amyk, bsaleil
2020-11-16 10:35:31 -06:00
Yuanfang Chen a223354161 [CGProfile] allows bitcast in metadata node storing function pointers
For example,  during RAUW in IRMover, the `Function` ValueAsMetadata in "CG Profile" could become bitcast.

Reviewed By: tejohnson

Differential Revision: https://reviews.llvm.org/D88433
2020-11-13 09:28:21 -08:00
Jessica Paquette b184a2eccf [GlobalISel] Add matchers for specific constants and a matcher for negations
It's fairly common to need matchers for a specific constant value, or for
common idioms like finding a negated register.

Add

- `m_SpecificICst`, which returns true when matching a specific value..
- `m_ZeroInt`, which returns true when an integer 0 is matched.
- `m_Neg`, which returns when a register is negated.

Also update a few places which use idioms related to the new matchers.

Differential Revision: https://reviews.llvm.org/D91397
2020-11-13 09:24:54 -08:00
Matt Arsenault c67e1a985f GlobalISel: Directly expose getDefSrcRegIgnoringCopies utility
It's useful to get both the instruction and register at the same time.
2020-11-13 11:07:04 -05:00
Djordje Todorovic 22fd38d508 [NFC][IntrRefLDV] Remove dead code from transferSpillOrRestoreInst()
Differential Revision: https://reviews.llvm.org/D90852
2020-11-13 07:53:54 -08:00
Hans Wennborg 105ed27ed8 Revert "[AsmPrinter] fix -disable-debug-info option"
The test fails on Mac, see comment on the code review.

> This option was in a rather convoluted place, causing global parameters
> to be set in awkward and undesirable ways to try to account for it
> indirectly. Add tests for the -disable-debug-info option and ensure we
> don't print unintended markers from unintended places.
>
> Reviewed By: dstenb
>
> Differential Revision: https://reviews.llvm.org/D91083

This reverts commit 9606ef03f0.
2020-11-13 13:46:13 +01:00
Kerry McLaughlin 306c8ab208 [SVE][CodeGen] Improve codegen of scalable masked scatters
If the scatter store is able to perform the sign/zero extend of
its index, this is folded into the instruction with refineIndexType().
Additionally, refineUniformBase() will return the base pointer and index
from an add + splat_vector.

Reviewed By: sdesmalen

Differential Revision: https://reviews.llvm.org/D90942
2020-11-13 11:19:36 +00:00
serge-sans-paille 9218ff50f9 llvmbuildectomy - replace llvm-build by plain cmake
No longer rely on an external tool to build the llvm component layout.

Instead, leverage the existing `add_llvm_componentlibrary` cmake function and
introduce `add_llvm_component_group` to accurately describe component behavior.

These function store extra properties in the created targets. These properties
are processed once all components are defined to resolve library dependencies
and produce the header expected by llvm-config.

Differential Revision: https://reviews.llvm.org/D90848
2020-11-13 10:35:24 +01:00
Jameson Nash 9606ef03f0 [AsmPrinter] fix -disable-debug-info option
This option was in a rather convoluted place, causing global parameters
to be set in awkward and undesirable ways to try to account for it
indirectly. Add tests for the -disable-debug-info option and ensure we
don't print unintended markers from unintended places.

Reviewed By: dstenb

Differential Revision: https://reviews.llvm.org/D91083
2020-11-13 00:58:09 -05:00
Simon Pilgrim 8996742741 [KnownBits] Add KnownBits::makeConstant helper. NFCI.
Helper for cases where we need to create a KnownBits from a (fully known) constant value.
2020-11-12 16:16:04 +00:00
David Sherwood 3225fcf11e [SVE] Deal with SVE tuple call arguments correctly when running out of registers
When passing SVE types as arguments to function calls we can run
out of hardware SVE registers. This is normally fine, since we
switch to an indirect mode where we pass a pointer to a SVE stack
object in a GPR. However, if we switch over part-way through
processing a SVE tuple then part of it will be in registers and
the other part will be on the stack.

I've fixed this by ensuring that:

1. When we don't have enough registers to allocate the whole block
   we mark any remaining SVE registers temporarily as allocated.
2. We temporarily remove the InConsecutiveRegs flags from the last
   tuple part argument and reinvoke the autogenerated calling
   convention handler. Doing this prevents the code from entering
   an infinite recursion and, in combination with 1), ensures we
   switch over to the Indirect mode.
3. After allocating a GPR register for the pointer to the tuple we
   then deallocate any SVE registers we marked as allocated in 1).
   We also set the InConsecutiveRegs flags back how they were before.
4. I've changed the AArch64ISelLowering LowerCALL and
   LowerFormalArguments functions to detect the start of a tuple,
   which involves allocating a single stack object and doing the
   correct numbers of legal loads and stores.

Differential Revision: https://reviews.llvm.org/D90219
2020-11-12 08:41:50 +00:00
Pavel Iliin fdb979cfbb [NFC] [Legalize] Fix spaces and style. 2020-11-11 19:24:15 +00:00
Hans Wennborg 418f18c6cd Revert "Reland [CFGuard] Add address-taken IAT tables and delay-load support"
This broke both Firefox and Chromium (PR47905) due to what seems like dllimport
function not being handled correctly.

> This patch adds support for creating Guard Address-Taken IAT Entry Tables (.giats$y sections) in object files, matching the behavior of MSVC. These contain lists of address-taken imported functions, which are used by the linker to create the final GIATS table.
> Additionally, if any DLLs are delay-loaded, the linker must look through the .giats tables and add the respective load thunks of address-taken imports to the GFIDS table, as these are also valid call targets.
>
> Reviewed By: rnk
>
> Differential Revision: https://reviews.llvm.org/D87544

This reverts commit cfd8481da1.
2020-11-11 16:03:33 +01:00
Simon Pilgrim 1a62ca65c1 [KnownBits] Add KnownBits::commonBits helper. NFCI.
We have a frequent pattern where we're merging two KnownBits to get the common/shared bits, and I just fell for the gotcha where I tried to use the & operator to merge them........
2020-11-11 12:15:54 +00:00
Kerry McLaughlin 170947a5de [SVE][CodeGen] Lower scalable masked scatters
Lowers the llvm.masked.scatter intrinsics (scalar plus vector addressing mode only)

Changes included in this patch:
 - Custom lowering for MSCATTER, which chooses the appropriate scatter store opcode to use.
    Floating-point scatters are cast to integer, with patterns added to match FP reinterpret_casts.
 - Added the getCanonicalIndexType function to convert redundant addressing
   modes (e.g. scaling is redundant when accessing bytes)
 - Tests with 32 & 64-bit scaled & unscaled offsets

Reviewed By: sdesmalen

Differential Revision: https://reviews.llvm.org/D90941
2020-11-11 11:50:22 +00:00
Kerry McLaughlin ffbbfc76ca [SVE][CodeGen] Add the isTruncatingStore flag to MSCATTER
This patch adds the IsTruncatingStore flag to MaskedScatterSDNode, set by getMaskedScatter().
Updated SelectionDAGDumper::print_details for MaskedScatterSDNode to print
the details of masked scatters (is truncating, signed or scaled).

This is the first in a series of patches which adds support for scalable masked scatters

Reviewed By: sdesmalen

Differential Revision: https://reviews.llvm.org/D90939
2020-11-11 10:58:24 +00:00
Chen Zheng 09e34048bf [SelectionDAG] fminnum should be a binary operator
Reviewed By: craig.topper

Differential Revision: https://reviews.llvm.org/D91163
2020-11-11 03:41:40 -05:00
Xun Li b8a8ef3276 [SafeStack] Make sure SafeStack does not break musttail call contract
SafeStack instrumentation should not insert anything inbetween musttail call and return instruction.
For every ReturnInst that needs to be instrumented, we adjust the insertion point to the musttail call if exists.

Differential Revision: https://reviews.llvm.org/D90702
2020-11-10 20:46:05 -08:00
Gaurav Jain a0b7129767 [NFC] Use [MC]Register in TwoAddressInstructionPass
Differential Revision: https://reviews.llvm.org/D90902
2020-11-10 19:01:56 -08:00
David Green b2ac9681a7 [ARM] Alter t2DoLoopStart to define lr
This changes the definition of t2DoLoopStart from
t2DoLoopStart rGPR
to
GPRlr = t2DoLoopStart rGPR

This will hopefully mean that low overhead loops are more tied together,
and we can more reliably generate loops without reverting or being at
the whims of the register allocator.

This is a fairly simple change in itself, but leads to a number of other
required alterations.

 - The hardware loop pass, if UsePhi is set, now generates loops of the
   form:
       %start = llvm.start.loop.iterations(%N)
     loop:
       %p = phi [%start], [%dec]
       %dec = llvm.loop.decrement.reg(%p, 1)
       %c = icmp ne %dec, 0
       br %c, loop, exit
 - For this a new llvm.start.loop.iterations intrinsic was added, identical
   to llvm.set.loop.iterations but produces a value as seen above, gluing
   the loop together more through def-use chains.
 - This new instrinsic conceptually produces the same output as input,
   which is taught to SCEV so that the checks in MVETailPredication are not
   affected.
 - Some minor changes are needed to the ARMLowOverheadLoop pass, but it has
   been left mostly as before. We should now more reliably be able to tell
   that the t2DoLoopStart is correct without having to prove it, but
   t2WhileLoopStart and tail-predicated loops will remain the same.
 - And all the tests have been updated. There are a lot of them!

This patch on it's own might cause more trouble that it helps, with more
tail-predicated loops being reverted, but some additional patches can
hopefully improve upon that to get to something that is better overall.

Differential Revision: https://reviews.llvm.org/D89881
2020-11-10 15:57:58 +00:00
Mirko Brkusanin a75d6178b8 [GlobalISel] Add combine for (x | mask) -> x when (x | mask) == x
If we have a mask, and a value x, where (x | mask) == x, we can drop the OR
and just use x.

Differential Revision: https://reviews.llvm.org/D90952
2020-11-10 11:32:13 +01:00
Mirko Brkusanin fb36ab0a42 [GlobalISel] Expand combine for (x & mask) -> x when (x & mask) == x
We can use KnownBitsAnalysis to cover cases when mask is not trivial. It can
also help with cases when mask is not constant but can still be folded into
one. Since 'and' is comutative we should treat both operands as possible
replacements.

Differential Revision: https://reviews.llvm.org/D90674
2020-11-10 11:32:13 +01:00
Mirko Brkusanin 53ae95c946 [AMDGPU][GlobalISel] Combine shift + logic + shift with constant operands
This sequence of instructions can be simplified if they are single use and
some operands are constants. Additional combines may be applied afterwards.

Differential Revision: https://reviews.llvm.org/D90223
2020-11-10 11:32:13 +01:00
Mirko Brkusanin de719586a8 [AMDGPU][GlobalISel] Fold a chain of two shift instructions with constant operands
Sequence of same shift instructions with constant operands can be combined into
a single shift instruction.

Differential Revision: https://reviews.llvm.org/D90217
2020-11-10 11:32:12 +01:00
David Zarzycki a41ea782c8 [SelectionDAG] Enable CTPOP optimization fine tuning
Add a TLI hook to allow SelectionDAG to fine tune the conversion of CTPOP to a chain of "x & (x - 1)" when CTPOP isn't legal.

A subsequent patch will attempt to fine tune the X86 code gen.

Reviewed By: spatel

Differential Revision: https://reviews.llvm.org/D89952
2020-11-09 13:49:01 -05:00
Paul Robinson 920befb337 [FastISel] Reduce spills around mem-intrinsic calls
FastISel generates instructions to materialize "local values" at the
top of a block, in the hope that these values could be reused within
the block.  To reduce spills and restores, FastISel treats calls as
sub-block boundaries, flushing the "local value map" at each call.

This patch treats the mem* intrinsics as if they were calls, because
at O0 generally they are calls.  Eliminating these spills/restores is
actually better for debugging (especially a "continue at this line"
command), code size, stack frame size, and maybe even performance.

Differential Revision: https://reviews.llvm.org/D90877
2020-11-09 09:45:14 -08:00
jasonliu 42d2109380 [XCOFF] Enable explicit sections on AIX
Implement mechanism to allow explicit sections to be generated on AIX.

Reviewed By: DiggerLin

Differential Revision: https://reviews.llvm.org/D88615
2020-11-09 16:27:38 +00:00
David Zarzycki 57e46e7123 [SelectionDAG] NFC: Hoist is legal check
This was requested during the code review of D89952.
2020-11-09 10:55:15 -05:00
Francesco Petrogalli fc2fe6817e [llvm][AArch64] Simplify (and (sign_extend..) #bitmask).
Fold

    VT = (and (sign_extend NarrowVT to VT) #bitmask)

into

    VT = (zero_extend NarrowVT)

With this combine, the test replaces a sign extended load + an
unsigned extention with a zero extended load to render one of the
operands of the last multiplication.

  BEFORE                       |  AFTER
    f_i16_i32:                 |    f_i16_i32:
         .fnstart              |           .fnstart
         ldrsh   r0, [r0]      |           ldrh    r1, [r1]
         ldrsh   r1, [r1]      |           ldrsh   r0, [r0]
         smulbb  r0, r1, r0    |           smulbb  r0, r0, r1
         uxth    r1, r1        |           mul     r0, r0, r1
         mul     r0, r0, r1    |           bx      lr
         bx      lr            |

Reviewed By: resistor

Differential Revision: https://reviews.llvm.org/D90605
2020-11-09 12:53:36 +00:00
Fangrui Song ee4769687d AsmPrinter/Dwarf*: Use llvm::Register instead of unsigned 2020-11-06 21:00:28 -08:00
Fangrui Song 7684496035 [AsmPrinter] Rename ByteStreamer::EmitInt8 to emitInt8
to be consistent with other emit*
2020-11-06 20:02:56 -08:00
Quentin Colombet a585228027 Prevent LICM and machineLICM from hoisting convergent operations
Results of convergent operations are implicitly affected by the
enclosing control flows and should not be hoisted out of arbitrary
loops.

Patch by Xiaoqing Wu <xiaoqing_wu@apple.com>

Differential Revision: https://reviews.llvm.org/D90361
2020-11-06 10:26:39 -08:00
Than McIntosh b3d0f02861 [NFC] Fix typo in comment.
Differential Revision: https://reviews.llvm.org/D90846
2020-11-06 09:03:07 -05:00
Momchil Velikov 5b30d9adc0 [MachineOutliner] Do not outline debug instructions
The debug location is removed from any outlined instruction. This
causes the MachineVerifier to crash on outlined DBG_VALUE
instructions.

Then, debug instructions are "invisible" to the outliner, that is, two
ranges of instructions from different functions are considered
identical if the only difference is debug instructions. Since a debug
instruction from one function is unlikely to provide sensible debug
information about all functions, sharing an outlined sequence, this
patch just removes debug instructions from the outlined functions.

Differential Revision: https://reviews.llvm.org/D89485
2020-11-05 19:26:51 +00:00
Craig Topper 98d7e583db [LegalizeTypes] Remove unnecessary if around switch in ScalarizeVectorOperand and SplitVectorOperand. NFC
The if was checking !Res.getNode() but that's always true since
Res was initialized to SDValue() and not touched before the if.

This appears to be a leftover from a previous implementation of
Custom legalization where Res was updated instead of returning
immediately.
2020-11-05 11:00:51 -08:00
Simon Pilgrim bf04e34383 [DAG] computeKnownBits - Replace ISD::SREM handling with KnownBits::srem to reduce code duplication 2020-11-05 17:12:58 +00:00
Simon Pilgrim 7fe7c6d3be [GlobalISel] Don't use Register type for getNumOperands(). NFCI.
Copy+Paste typo - we were storing getNumOperands() opcounts in a Register type instead of just an unsigned.
2020-11-05 17:12:58 +00:00
Simon Pilgrim e237d56b43 [KnownBits] Move ValueTracking/SelectionDAG UREM KnownBits handling to KnownBits::urem. NFCI.
Both these have the same implementation - so move them to a single KnownBits copy.

GlobalISel will be able to use this as well with minimal effort.
2020-11-05 14:30:59 +00:00
Simon Pilgrim 32bee18b84 [KnownBits] Move ValueTracking/SelectionDAG UDIV KnownBits handling to KnownBits::udiv. NFCI.
Both these have the same implementation - so move them to a single KnownBits copy.

GlobalISel will be able to use this as well with minimal effort.
2020-11-05 13:42:42 +00:00
Simon Pilgrim 546d002d7a [GlobalISel] ComputeKnownBits - use common KnownBits shift handling (PR44526)
Convert GISelKnownBits.computeKnownBitsImpl shift handling to use the common KnownBits implementations, which makes use of the known leading/trailing bits for shifted values in cases where we don't know the shift amount value, as detailed in https://blog.regehr.org/archives/1709

Differential Revision: https://reviews.llvm.org/D90527
2020-11-05 11:52:26 +00:00
Sander de Smalen d57bba7cf8 [SVE] Return StackOffset for TargetFrameLowering::getFrameIndexReference.
To accommodate frame layouts that have both fixed and scalable objects
on the stack, describing a stack location or offset using a pointer + uint64_t
is not sufficient. For this reason, we've introduced the StackOffset class,
which models both the fixed- and scalable sized offsets.

The TargetFrameLowering::getFrameIndexReference is made to return a StackOffset,
so that this can be used in other interfaces, such as to eliminate frame indices
in PEI or to emit Debug locations for variables on the stack.

This patch is purely mechanical and doesn't change the behaviour of how
the result of this function is used for fixed-sized offsets. The patch adds
various checks to assert that the offset has no scalable component, as frame
offsets with a scalable component are not yet supported in various places.

Reviewed By: arsenm

Differential Revision: https://reviews.llvm.org/D90018
2020-11-05 11:02:18 +00:00
Simon Pilgrim b25765792b Revert rGbbeb08497ce58 "Revert "[GlobalISel] GISelKnownBits::computeKnownBitsImpl - Replace TargetOpcode::G_MUL handling with the common KnownBits::computeForMul implementation""
Updated the GISel KnownBits tests as KnownBits::computeForMul allows more accurate computation.
2020-11-05 10:39:53 +00:00
Chen Zheng f645cea8f6 [MachineSink] add more profitable pattern.
Add more profitable sinking patterns if the target bb register pressure
is not too high.

Reviewed By: qcolombet

Differential Revision: https://reviews.llvm.org/D88126
2020-11-04 23:11:22 -05:00
Cameron McInally c126eb7529 [SelectionDAG] Add legalizations for VECREDUCE_SEQ_FMUL
Hook up legalizations for VECREDUCE_SEQ_FMUL. This is following up on the VECREDUCE_SEQ_FADD work from D90247.

Differential Revision: https://reviews.llvm.org/D90644
2020-11-04 14:20:31 -06:00
Fraser Cormack f99580c1e5 [DAGCombine] Fix bug in load scalarization
Summary:
For vector element types which are not byte-sized, we would generate
incorrect scalar offsets and produce incorrect codegen.

This optimization could potentially be supported in the future, e.g. by
loading in bytes, then shifting and masking out the remaining bits of
the vector element. However, without an upstream target to test against
it's best to avoid the bad codegen in the simplest possible way.

Related to this bug:

  https://bugs.llvm.org/show_bug.cgi?id=27600

Reviewed by: foad

Differential Revision: https://reviews.llvm.org/D78568
2020-11-04 19:02:40 +00:00
Fangrui Song bbeb08497c Revert "[GlobalISel] GISelKnownBits::computeKnownBitsImpl - Replace TargetOpcode::G_MUL handling with the common KnownBits::computeForMul implementation"
This reverts commit 0b8711e1af which broke GlobalISelTests AArch64GISelMITest.TestKnownBits
2020-11-04 09:54:04 -08:00
Simon Pilgrim 0b8711e1af [GlobalISel] GISelKnownBits::computeKnownBitsImpl - Replace TargetOpcode::G_MUL handling with the common KnownBits::computeForMul implementation
Avoid code duplication
2020-11-04 17:25:24 +00:00
Simon Pilgrim 93c2a9ae07 Use isa<> instead of dyn_cast<> to avoid unused variable warning. NFCI. 2020-11-04 15:26:32 +00:00
Kerry McLaughlin f2412d372d [SVE][CodeGen] Lower scalable integer vector reductions
This patch uses the existing LowerFixedLengthReductionToSVE function to also lower
scalable vector reductions. A separate function has been added to lower VECREDUCE_AND
& VECREDUCE_OR operations with predicate types using ptest.

Lowering scalable floating-point reductions will be addressed in a follow up patch,
for now these will hit the assertion added to expandVecReduce() in TargetLowering.

Reviewed By: paulwalker-arm

Differential Revision: https://reviews.llvm.org/D89382
2020-11-04 11:38:49 +00:00
Simon Pilgrim 825e517e34 [DAG] computeKnownBits - Replace ISD::MUL handling with the common KnownBits::computeForMul implementation 2020-11-04 11:32:08 +00:00