Commit Graph

29920 Commits

Author SHA1 Message Date
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
Fangrui Song 0314dff051 [DebugInfo] Delete unused DwarfUnit::addConstantFPValue & addConstantValue overloads. NFC
This functions appear to be unused for many years.
2020-11-04 00:05:57 -08:00
Xiang1 Zhang 7ba3293691 [StackColoring] Conservatively merge catch point of V for catch(V)
Reviewed By: thanm, clin1

Differential Revision: https://reviews.llvm.org/D86673
2020-11-04 10:49:56 +08:00
Michael Liao 4b11201592 [MachineInstr] Add support for instructions with multiple memory operands.
- Basically iterate each pair of memory operands from both instructions
  and return true if any of them may alias.
- The exception are memory instructions without any memory operand. They
  may touch everything and could alias to any memory instruction.

Differential Revision: https://reviews.llvm.org/D89447
2020-11-03 20:44:40 -05:00
Gaurav Jain 492b1d78d5 [NFC] Use [MC]Register in register allocation
Differential Revision: https://reviews.llvm.org/D90725
2020-11-03 17:34:26 -08:00
Simon Pilgrim e9b88c754a [DAG] computeKnownBits - Move ISD::SRA handling into KnownBits::ashr
As discussed on D90527, we should be trying to move shift handling functionality into KnownBits to avoid code duplication in SelectionDAG/GlobalISel/ValueTracking.
2020-11-03 18:09:33 +00:00
Simon Pilgrim cb798f040a [DAG] computeKnownBits - Move (most) ISD::SRL handling into KnownBits::lshr
As discussed on D90527, we should be be trying to move shift handling functionality into KnownBits to avoid code duplication in SelectionDAG/GlobalISel/ValueTracking.

The refactor to use the KnownBits fixed/min/max constant helpers allows us to hit a couple of cases that we were missing before.

We still need the getValidMinimumShiftAmountConstant case as KnownBits doesn't handle per-element vector cases.
2020-11-03 17:30:36 +00:00
Jameson Nash a0ad066ce4 make the AsmPrinterHandler array public
This lets external consumers customize the output, similar to how
AssemblyAnnotationWriter lets the caller define callbacks when printing
IR. The array of handlers already existed, this just cleans up the code
so that it can be exposed publically.

Replaces https://reviews.llvm.org/D74158

Differential Revision: https://reviews.llvm.org/D89613
2020-11-03 10:02:09 -05:00
Simon Pilgrim cab21d4fa8 [DAG] computeKnownBits - Move (most) ISD::SHL handling into KnownBits::shl
As discussed on D90527, we should be be trying to move shift handling functionality into KnownBits to avoid code duplication in SelectionDAG/GlobalISel/ValueTracking.

The refactor to use the KnownBits fixed/min/max constant helpers allows us to hit a couple of cases that we were missing before.

We still need the getValidMinimumShiftAmountConstant case as KnownBits doesn't handle per-element vector cases.
2020-11-03 14:22:28 +00:00
Hans Wennborg cbf25fbed5 Revert "[CodeGen] [WinException] Only produce handler data at the end of the function if needed"
This caused an explosion in ICF times during linking on Windows when libfuzzer
instrumentation is enabled. For a small binary we see ICF time go from ~0 to
~10 s. For a large binary it goes from ~1 s to forevert (I gave up after 30
minutes).

See comment on the code review.

> If we are going to write handler data (that is written as variable
> length data following after the unwind info in .xdata), we need to
> emit the handler data immediately, but for cases where no such
> info is going to be written, skip emitting it right away. (Unwind
> info for all remaining functions that hasn't gotten it emitted
> directly is emitted at the end.)
>
> This does slightly change the ordering of sections (triggering a
> bunch of updates to DebugInfo/COFF tests), but the change should be
> benign.
>
> This also matches GCC's assembly output, which doesn't output
> .seh_handlerdata unless it actually is needed.
>
> For ARM64, the unwind info can be packed into the runtime function
> entry itself (leaving no data in the .xdata section at all), but
> that can only be done if there's no follow-on data in the .xdata
> section. If emission of the unwind info is triggered via
> EmitWinEHHandlerData (or the .seh_handlerdata directive), which
> implicitly switches to the .xdata section, there's a chance of the
> caller wanting to pass further data there, so the packed format
> can't be used in that case.
>
> Differential Revision: https://reviews.llvm.org/D87448

This reverts commit 36c64af9d7.
2020-11-03 13:12:10 +01:00
Jessica Clarke f77c8a48ae [CodeGen] Fix regression from D83655
Arm EHABI has a null LSDASection as it does its own thing, so we should
continue to return null in that case rather than try and cast it.
2020-11-03 03:57:46 +00:00
Gaurav Jain b68994bd2d [NFC] Use [MC]Register in Live-ness tracking
Differential Revision: https://reviews.llvm.org/D90611
2020-11-02 15:46:13 -08:00
Fangrui Song ee5d1a0449 [AsmPrinter] Split up .gcc_except_table
MC currently produces monolithic .gcc_except_table section. GCC can split up .gcc_except_table:

* if comdat: `.section .gcc_except_table._Z6comdatv,"aG",@progbits,_Z6comdatv,comdat`
* otherwise, if -ffunction-sections: `.section .gcc_except_table._Z3fooi,"a",@progbits`

This ensures that (a) non-prevailing copies are discarded and (b)
.gcc_except_table associated to discarded text sections can be discarded by a
.gcc_except_table-aware linker (GNU ld, but not gold or LLD)

This patches matches the GCC behavior. If -fno-unique-section-names is
specified, we don't append the suffix. If -ffunction-sections is additionally specified,
use `.section ...,unique`.

Note, if clang driver communicates that the linker is LLD and we know it
is new (11.0.0 or later) we can use SHF_LINK_ORDER to avoid string table
costs, at least in the -fno-unique-section-names case. We cannot use it on GNU
ld because as of binutils 2.35 it does not support mixed SHF_LINK_ORDER &
non-SHF_LINK_ORDER components in an output section
https://sourceware.org/bugzilla/show_bug.cgi?id=26256

For RISC-V -mrelax, this patch additionally fixes an assembler-linker
interaction problem: because a section is shrinkable, the length of a call-site
code range is not a constant. Relocations referencing the associated text
section (STT_SECTION) are needed. However, a STB_LOCAL relocation referencing a
discarded section group member from outside the group is disallowed by the ELF
specification (PR46675):

```
// a.cc
inline int comdat() { try { throw 1; } catch (int) { return 1; } return 0; }
int main() { return comdat(); }

// b.cc
inline int comdat() { try { throw 1; } catch (int) { return 1; } return 0; }
int foo() { return comdat(); }

clang++ -target riscv64-linux -c a.cc b.cc -fPIC -mno-relax
ld.lld -shared a.o b.o => ld.lld: error: relocation refers to a symbol in a discarded section:
```

-fbasic-block-sections= is similar to RISC-V -mrelax: there are outstanding relocations.

Reviewed By: jrtc27, rahmanl

Differential Revision: https://reviews.llvm.org/D83655
2020-11-02 14:36:25 -08:00
Mircea Trofin 61e8a44655 [NFC][regalloc] Use MCRegister appropriately
Differential Revision: https://reviews.llvm.org/D90506
2020-11-02 11:48:49 -08:00
Alex Richardson 5bc438efcf [AtomicExpand] Avoid creating an unnamed libcall
I recently modified this pass to better support CHERI-RISC-V and while
doing so I noticed that this pass was calling M->getOrInsertFunction()
with the result of TLI->getLibcallName(RTLibType). However, AMDGPU fills
the libcalls array with nullptr, so this creates an anonymous function
instead. This patch changes expandAtomicOpToLibcall to return false in
case the libcall does not exist and changes the assert() in the callees to
a report_fatal_error() instead.

Reviewed By: arsenm

Differential Revision: https://reviews.llvm.org/D88800
2020-11-02 17:52:37 +00:00
Matt Arsenault b3639e9ae9 RegisterCoalescer: Use Register 2020-11-02 10:14:50 -05:00
Chen Zheng 24a31922ce [MachineSink] sink more profitable loads
Reviewed By: qcolombet

Differential Revision: https://reviews.llvm.org/D86864
2020-11-01 21:13:27 -05:00
QingShan Zhang 1d178d600a [Scheduling] Fall back to the fast cluster algorithm if the DAG is too complex
We have added a new load/store cluster algorithm in D85517. However, AArch64 see
some compiling deg with the new algorithm as the IsReachable() is not cheap if
the DAG is complex. O(M+N) See https://bugs.llvm.org/show_bug.cgi?id=47966
So, this patch added a heuristic to switch to old cluster algorithm if the DAG is too complex.

Reviewed By: Owen Anderson

Differential Revision: https://reviews.llvm.org/D90144
2020-11-02 02:11:52 +00:00
Qiu Chaofan 1f852ba853 [PowerPC] Avoid unnecessary fadd for unsigned to ppcf128
Unsigned 32-bit or shorter integer to ppcf128 conversion are currently
expanded as signed-to-double with an extra fadd to 'complement'. But on
PowerPC we have native instruction to directly convert unsigned to
double since ISA v2.06. This patch exploits it.

Reviewed By: efriedma

Differential Revision: https://reviews.llvm.org/D89786
2020-11-01 23:22:47 +08:00
Cameron McInally dda1e74b58 [Legalize] Add legalizations for VECREDUCE_SEQ_FADD
Add Legalization support for VECREDUCE_SEQ_FADD, so that we don't need to depend on ExpandReductionsPass.

Differential Revision: https://reviews.llvm.org/D90247
2020-10-30 16:02:55 -05:00
Amy Huang 7156910d85 [CodeView] Encode signed int values correctly when emitting S_CONSTANTs
Differential Revision: https://reviews.llvm.org/D90199
2020-10-30 09:28:41 -07:00
Nikita Popov 6c2ad4cf87 [SDAG] Extract helper to determine neutral element (NFC)
Make the existing VECREDUCE based code more generic, but expressing
it in terms of the neutral value of the base opcode instead.
2020-10-29 22:05:06 +01:00
Nikita Popov a5f172927d [SDAG] Fix neutral value for vecreduce_fadd
The neutral value for FADD is -0.0, not 0.0, so this is what we
need to pad vectors with.
2020-10-29 21:27:59 +01:00
Nikita Popov 91bf172088 [SDAG] Extract helper to get vecreduce base opcode (NFC) 2020-10-29 20:22:22 +01:00
dfukalov b3cdaef518 [MIR] Fix out of bounds access in MIRPrinter.
Fixes: SWDEV-256460

Reviewed By: arsenm

Differential Revision: https://reviews.llvm.org/D90239
2020-10-29 14:35:06 +03:00
Alok Kumar Sharma 930a8c60b6 [DebugInfo] [NFCI] Adding a missed out line in support for DW_TAG_generic_subrange.
This commit adds a missed out line in earlier commit for DW_TAG_generic_subrange.
Previous commit ID: a6dd01afa3
Differential Revision: https://reviews.llvm.org/D89218
Thanks markus for pointing this out.
2020-10-29 16:18:20 +05:30
David Green a4b6b1e1c8 [InterleaveAccess] Recognise Interleave loads through binary operations
Instcombine will currently sink identical shuffles though vector binary
operations. This is probably generally useful, but can break up the code
pattern we use to represent an interleaving load group. This patch
reverses that in the InterleaveAccessPass to re-recognise the pattern of
shuffles sunk past binary operations and folds them back if an
interleave group can be created.

Differential Revision: https://reviews.llvm.org/D89489
2020-10-29 09:13:23 +00:00
Vedant Kumar ffba94a9ac Revert "[DebugInfo] Fix legacy ZExt emission when FromBits >= 64 (PR47927)"
This reverts commit 9905346221.

It breaks the compiler-rt build, see https://reviews.llvm.org/D89838
2020-10-28 18:57:17 -07:00
Vedant Kumar 4fe81b6b6a Revert "[DebugInfo] Shorten legacy [s|z]ext dwarf expressions"
This reverts commit 2ce36ebca5. It depends
on https://reviews.llvm.org/D89838, which needs to be reverted.
2020-10-28 18:57:17 -07:00
Derek Schuff 77973f8dee [WebAssembly] Add support for DWARF type units
Since Wasm comdat sections work similarly to ELF, we can use that mechanism
    to eliminate duplicate dwarf type information in the same way.

    Differential Revision: https://reviews.llvm.org/D88603
2020-10-28 17:41:22 -07:00
Amy Huang 7669f3c0f6 Recommit "[CodeView] Emit static data members as S_CONSTANTs."
We used to only emit static const data members in CodeView as
S_CONSTANTS when they were used; this patch makes it so they are always emitted.

This changes CodeViewDebug.cpp to find the static const members from the
class debug info instead of creating DIGlobalVariables in the IR
whenever a static const data member is used.

Bug: https://bugs.llvm.org/show_bug.cgi?id=47580

Differential Revision: https://reviews.llvm.org/D89072

This reverts commit 504615353f.
2020-10-28 16:35:59 -07:00
Gaurav Jain f719fd7ade [NFC] Use [MC]Register in CSE & LICM
Differential Revision: https://reviews.llvm.org/D90327
2020-10-28 15:53:26 -07:00
Alok Kumar Sharma a6dd01afa3 [DebugInfo] Support for DW_TAG_generic_subrange
This is needed to support fortran assumed rank arrays which
have runtime rank.

  Summary:
Fortran assumed rank arrays have dynamic rank. DWARF TAG
DW_TAG_generic_subrange is needed to support that.

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

Reviewed By: aprantl

Differential Revision: https://reviews.llvm.org/D89218
2020-10-29 01:34:15 +05:30
Aditya Nandakumar bed8394047 [GISel]: Few InsertVecElt combines
https://reviews.llvm.org/D88060

This adds the following combines
1) build_vector formation from insert_vec_elts
2) insert_vec_elts (build_vector) -> build_vector
2020-10-28 12:27:07 -07:00
Mircea Trofin f0a98ad820 [NFC] Use Register in RegisterPressure APIs
Some related changes as well.

Differential Revision: https://reviews.llvm.org/D90268
2020-10-28 12:14:08 -07:00
Vedant Kumar 2ce36ebca5 [DebugInfo] Shorten legacy [s|z]ext dwarf expressions
Take advantage of the emitConstu helper to emit slightly shorter dwarf
expressions to implement legacy [s|z]ext operations.
2020-10-28 12:06:02 -07:00
Vedant Kumar 9905346221 [DebugInfo] Fix legacy ZExt emission when FromBits >= 64 (PR47927)
Fix an out-of-bounds shift in emitLegacyZExt by using a slightly more
complicated dwarf expression to create the zext mask.

This addresses a UBSan diagnostic seen when compiling compiler-rt
(llvm.org/PR47927).

rdar://70307714

Differential Revision: https://reviews.llvm.org/D89838
2020-10-28 12:06:02 -07:00
Matt Arsenault b9c21d43bb RegAlloc: Clear isSSA
The MIR parser may infer SSA, so -run-pass=regallocgreedy would hit a
verifier error after multiple vreg defs are added.
2020-10-28 12:02:16 -04:00
Djordje Todorovic 6384378582 [NFC][IntrRefLDV] Improve the Value printing
Basically, this just improves the dump of the Value stored within a location.

If the defining instruction number is zero, it means it is "live-in".

Before the patch:

ESI --> bb 0 inst 0 loc ESI
After:

ESI --> Value{bb: 0, inst: live-in, loc: ESI}
This is an NFC.

Differential Revision: https://reviews.llvm.org/D90309
2020-10-28 07:39:08 -07:00
Simon Pilgrim f53d7f55f1 [DAG] Move canFoldInAddressingMode before foldBinOpIntoSelect. NFC.
Reduces the diff in D90113.
2020-10-28 12:16:05 +00:00
Luqman Aden 4c0a016927 Rename EHPersonality::MSVC_Win64SEH to EHPersonality::MSVC_TableSEH. NFC.
The types of SEH aren't x86(-32) vs x64 but rather stack-based exception chaining
vs table-based exception handling. x86-32 is the only arch for which Windows
uses the former. 32-bit ARM would use what is called Win64SEH today, which
is a bit confusing so instead let's just rename it to be a bit more clear.

Reviewed By: compnerd, rnk

Differential Revision: https://reviews.llvm.org/D90117
2020-10-27 23:22:13 -07:00
Derek Schuff 44eea0b1a7 Revert "[WebAssembly] Add support for DWARF type units"
This reverts commit bcb8a119df.
2020-10-27 17:57:32 -07:00
Derek Schuff bcb8a119df [WebAssembly] Add support for DWARF type units
Since Wasm comdat sections work similarly to ELF, we can use that mechanism
to eliminate duplicate dwarf type information in the same way.

Differential Revision: https://reviews.llvm.org/D88603
2020-10-27 17:13:41 -07:00
Nicolai Hähnle e025d09b21 Revert multiple patches based on "Introduce CfgTraits abstraction"
These logically belong together since it's a base commit plus
followup fixes to less common build configurations.

The patches are:

Revert "CfgInterface: rename interface() to getInterface()"

This reverts commit a74fc48158.

Revert "Wrap CfgTraitsFor in namespace llvm to please GCC 5"

This reverts commit f2a06875b6.

Revert "Try to make GCC5 happy about the CfgTraits thing"

This reverts commit 03a5f7ce12.

Revert "Introduce CfgTraits abstraction"

This reverts commit c0cdd22c72.
2020-10-27 20:33:30 +01:00
Amy Huang 504615353f Revert "[CodeView] Emit static data members as S_CONSTANTs."
Seems like there's an assert in here that we shouldn't be running into.

This reverts commit 515973222e.
2020-10-27 11:29:58 -07:00
Vedant Kumar 5a3ef55a52 [Utils] Skip RemoveRedundantDbgInstrs in MergeBlockIntoPredecessor (PR47746)
This patch changes MergeBlockIntoPredecessor to skip the call to
RemoveRedundantDbgInstrs, in effect partially reverting D71480 due to
some compile-time issues spotted in LoopUnroll and SimplifyCFG.

The call to RemoveRedundantDbgInstrs appears to have changed the
worst-case behavior of the merging utility. Loosely speaking, it seems
to have gone from O(#phis) to O(#insts).

It might not be possible to mitigate this by scanning a block to
determine whether there are any debug intrinsics to remove, since such a
scan costs O(#insts).

So: skip the call to RemoveRedundantDbgInstrs. There's surprisingly
little fallout from this, and most of it can be addressed by doing
RemoveRedundantDbgInstrs later. The exception is (the block-local
version of) SimplifyCFG, where it might just be too expensive to call
RemoveRedundantDbgInstrs.

Differential Revision: https://reviews.llvm.org/D88928
2020-10-27 10:12:59 -07:00
Djordje Todorovic cca049ad2b [NFC][IntrRefLDV] Some code clean up
As reading the source code, I've found some minor nits:
  -Use using instead of typedef
  -Fix a comment
  -Refactor

Differential Revision: https://reviews.llvm.org/D90155
2020-10-27 05:31:24 -07:00
Sven van Haastregt 5d03080092 [TargetLowering] Add i1 condition for bit comparison fold
For i1 types, boolean false is represented identically regardless of
the boolean content, so we can allow optimizations that otherwise
would not be correct for booleans with false represented as a negative
one.

Patch by Erik Hogeman.

Differential Revision: https://reviews.llvm.org/D90145
2020-10-27 12:22:20 +00:00
Med Ismail Bennani a3aea0193d [llvm/DebugInfo] Simplify DW_OP_implicit_value condition (NFC)
Signed-off-by: Med Ismail Bennani <medismail.bennani@gmail.com>
2020-10-27 11:25:19 +01:00
Gaurav Jain 17cdba61d4 [NFC] Use [MC]Register in RegAllocPBQP & RegisterCoalescer
Differential Revision: https://reviews.llvm.org/D90008
2020-10-26 17:13:32 -07:00
Rahman Lavaee 0b2f4cdf2b Explicitly check for entry basic block, rather than relying on MachineBasicBlock::pred_empty.
Sometimes in unoptimized code, we have dangling unreachable basic blocks with no predecessors. Basic block sections should be emitted for those as well. Without this patch, the included test fails with a fatal error in `AsmPrinter::emitBasicBlockEnd`.

Reviewed By: tmsriram

Differential Revision: https://reviews.llvm.org/D89423
2020-10-26 16:15:56 -07:00
Amy Huang 515973222e [CodeView] Emit static data members as S_CONSTANTs.
We used to only emit static const data members in CodeView as
S_CONSTANTS when they were used; this patch makes it so they are always emitted.

I changed CodeViewDebug.cpp to find the static const members from the
class debug info instead of creating DIGlobalVariables in the IR
whenever a static const data member is used.

Bug: https://bugs.llvm.org/show_bug.cgi?id=47580

Differential Revision: https://reviews.llvm.org/D89072
2020-10-26 15:30:35 -07:00
Peter Waller 5b742a0c10 [SVE][CodeGen][DAGCombiner] Fix TypeSize warning in redundant store elimination
The modified code in visitSTORE was missing a scalable vector check, and still
using the now deprecated implicit cast of TypeSize to uint64_t through the
overloaded operator. This patch fixes these issues.

This brings the logic in line with the comment on the context line immediately
above the added precondition.

Add a test in sve-redundant-store.ll that the warning is not triggered.

Differential Revision: https://reviews.llvm.org/D89701
2020-10-26 16:37:48 +00:00
Peter Waller 6536d6040f Revert "[SVE][CodeGen][DAGCombiner] Fix TypeSize warning in redundant store elimination"
This reverts commit 4604441386.

Reverting because it was not the intended version of the patch, which
follows this patch.
2020-10-26 16:37:00 +00:00
Peter Waller 4604441386 [SVE][CodeGen][DAGCombiner] Fix TypeSize warning in redundant store elimination
The modified code in visitSTORE was missing a scalable vector check, and still
using the now deprecated implicit cast of TypeSize to uint64_t through the
overloaded operator. This patch fixes these issues.

This brings the logic in line with the comment on the context line immediately
above the added precondition.

Add a test in Redundantstores.ll that the warning is not triggered.
2020-10-26 16:23:42 +00:00
Djordje Todorovic a64b2c9366 [NFC][InstrRefLDV] Fix a typo 2020-10-26 04:04:16 -07:00
Florian Hahn b2bec7cece [AsmPrinter] Add per BB instruction mix remark.
This patch adds a remarks that provides counts for each opcode per basic block.

An snippet of the generated information can be seen below.

The current implementation uses the target specific opcode for the counts. For example, on AArch64 this means we currently get 2 entries for `add` instructions if the block contains 32 and 64 bit adds. Similarly, immediate version are treated differently.

Unfortunately there seems to be no convenient way to get only the mnemonic part of the instruction as a string AFAIK. This could be improved in the future.

```
--- !Analysis
Pass:            asm-printer
Name:            InstructionMix
DebugLoc:        { File: arm64-instruction-mix-remarks.ll, Line: 30, Column: 30 }
Function:        foo
Args:
  - String:          'BasicBlock: '
  - BasicBlock:      else
  - String:          "\n"
  - String:          INST_MADDWrrr
  - String:          ': '
  - INST_MADDWrrr:   '2'
  - String:          "\n"
  - String:          INST_MOVZWi
  - String:          ': '
  - INST_MOVZWi:     '1'
```

Reviewed By: anemet, thegameg, paquette

Differential Revision: https://reviews.llvm.org/D89892
2020-10-26 09:25:45 +00:00
David Green 61bc18de0b [Schedule] Add a MultiHazardRecognizer
This adds a MultiHazardRecognizer and starts to make use of it in the
ARM backend. The idea of the class is to allow multiple independent
hazard recognizers to be added to a single base MultiHazardRecognizer,
allowing them to all work in parallel without requiring them to be
chained into subclasses. They can then be added or not based on cpu or
subtarget features, which will become useful in the ARM backend once
more hazard recognizers are being used for various things.

This also renames ARMHazardRecognizer to ARMHazardRecognizerFPMLx in the
process, to more clearly explain what that recognizer is designed for.

Differential Revision: https://reviews.llvm.org/D72939
2020-10-26 08:06:17 +00:00
Simon Pilgrim ce356e1546 [DAG] Add BuildVectorSDNode::getRepeatedSequence helper to recognise multi-element splat patterns
Replace the X86 specific isSplatZeroExtended helper with a generic BuildVectorSDNode method.

I've just used this to simplify the X86ISD::BROADCASTM lowering so far (and remove isSplatZeroExtended), but we should be able to use this in more places to lower to complex broadcast patterns.

Differential Revision: https://reviews.llvm.org/D87930
2020-10-24 12:23:09 +01:00
Simon Pilgrim 62b17a7697 [LegalizeTypes] Legalize vector rotate operations
Lower vector rotate operations as long as the legalization occurs outside of LegalizeVectorOps.

This fixes https://bugs.llvm.org/show_bug.cgi?id=47320

Patch By: @rsanthir.quic (Ryan Santhirarajan)

Differential Revision: https://reviews.llvm.org/D89497
2020-10-24 11:30:32 +01:00
Med Ismail Bennani 64c4dac60e
[llvm/DebugInfo] Emit DW_OP_implicit_value when tuning for LLDB
This patch enables emitting DWARF `DW_OP_implicit_value` opcode when
tuning debug information for LLDB (`-debugger-tune=lldb`).

This will also propagate to Darwin platforms, since they use LLDB tuning
as a default.

rdar://67406059

Differential Revision: https://reviews.llvm.org/D90001

Signed-off-by: Med Ismail Bennani <medismail.bennani@gmail.com>
2020-10-24 06:45:33 +02:00
Mehdi Amini 8f492f6467 Remove unused verifyRegStateMapping() function in RegAllocFast (NFC)
This fixes compiler warning when building with assertions.
2020-10-24 00:36:51 +00:00
Cameron McInally a1cc274cb3 [SVE] Lower fixed length VECREDUCE_SEQ_FADD operation
Differential Revision: https://reviews.llvm.org/D89162
2020-10-23 16:24:02 -05:00
Nick Desaulniers b7926ce6d7 [IR] add fn attr for no_stack_protector; prevent inlining on mismatch
It's currently ambiguous in IR whether the source language explicitly
did not want a stack a stack protector (in C, via function attribute
no_stack_protector) or doesn't care for any given function.

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

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

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

Fixes pr/47479.

Reviewed By: void

Differential Revision: https://reviews.llvm.org/D87956
2020-10-23 11:55:39 -07:00
Mircea Trofin 819044ad2d [NFC] Use [MC]Register in RegAllocGreedy
This was initiated from the uses of MCRegUnitIterator, so while likely
not exhaustive, it's a step forward.

Differential Revision: https://reviews.llvm.org/D89975
2020-10-23 11:30:53 -07:00
Paulo Matos 69e2797eae [WebAssembly] Implementation of (most) table instructions
Implementation of instructions table.get, table.set, table.grow,
table.size, table.fill, table.copy.

Missing instructions are table.init and elem.drop as they deal with
element sections which are not yet implemented.

Added more tests to tables.s

Differential Revision: https://reviews.llvm.org/D89797
2020-10-23 08:42:54 -07:00
Jeremy Morse b1b2c6ab66 [DebugInstrRef] Handle DBG_INSTR_REFs use-before-defs in LiveDebugValues
Deciding where to place debugging instructions when normal instructions
sink between blocks is difficult -- see PR44117. Dealing with this with
instruction-referencing variable locations is simple: we just tolerate
DBG_INSTR_REFs referring to values that haven't been computed yet. This
patch adds support into InstrRefBasedLDV to record when a variable value
appears in the middle of a block, and should have a DBG_VALUE added when it
appears (a debug use before def).

While described simply, this relies heavily on the value-propagation
algorithm in InstrRefBasedLDV. The implementation doesn't attempt to verify
the location of a value unless something non-trivial occurs to merge
variable values in vlocJoin. This means that a variable with a value that
has no location can retain it across all control flow (including loops).
It's only when another debug instruction specifies a different variable
value that we have to check, and find there's no location.

This property means that if a machine value is defined in a block dominated
by a DBG_INSTR_REF that refers to it, all the successor blocks can
automatically find a location for that value (if it's not clobbered). Thus
in a sense, InstrRefBasedLDV is already supporting and implementing
use-before-defs. This patch allows us to specify a variable location in the
block where it's defined.

When loading live-in variable locations, TransferTracker currently discards
those where it can't find a location for the variable value. However, we
can tell from the machine value number whether the value is defined in this
block. If it is, add it to a set of use-before-def records. Then, once the
relevant instruction has been processed, emit a DBG_VALUE immediately after
it.

Differential Revision: https://reviews.llvm.org/D85775
2020-10-23 16:33:23 +01:00
Denis Antrushin 4f7ee55971 Revert "[Statepoints] Allow deopt GC pointer on VReg if gc-live bundle is empty."
Downstream testing revealed some problems with this patch.
Reverting while investigating.
This reverts commit 2b96dcebfa.
2020-10-23 21:55:06 +07:00
Jeremy Morse 68f4715716 [DebugInstrRef] Convert DBG_INSTR_REFs into variable locations
Handle DBG_INSTR_REF instructions in LiveDebugValues, to determine and
propagate variable locations. The logic is fairly straight forwards:
Collect a map of debug-instruction-number to the machine value numbers
generated in the first walk through the function. When building the
variable value transfer function and we see a DBG_INSTR_REF, look up the
instruction it refers to, and pick the machine value number it generates,
That's it; the rest of LiveDebugValues continues as normal.

Awkwardly, there are two kinds of instruction numbering happening here: the
offset into the block (which is how machine value numbers are determined),
and the numbers that we label instructions with when generating
DBG_INSTR_REFs.

I've also restructured the TransferTracker redefVar code a little, to
separate some DBG_VALUE specific operations into its own method. The
changes around redefVar should be largely NFC, while allowing
DBG_INSTR_REFs to specify a value number rather than just a location.

Differential Revision: https://reviews.llvm.org/D85771
2020-10-23 14:50:02 +01:00
Jeremy Morse ab93e71065 [DebugInstrRef] NFC: Separate collection of machine/variable values
This patch adjusts _when_ something happens in LiveDebugValues /
InstrRefBasedLDV, to make it more amenable to dealing with DBG_INSTR_REF
instructions. There's no functional change.

In the current InstrRefBasedLDV implementation, we collect the machine
value-number transfer function for blocks at the same time as the
variable-value transfer function. After solving machine value numbers, the
variable-value transfer function is updated so that DBG_VALUEs of live-in
registers have the correct value. The same would need to be done for
DBG_INSTR_REFs, to connect instruction-references with machine value
numbers.

Rather than writing more code for that, this patch separates the two: we
collect the (machine-value-number) transfer function and solve for
machine value numbers, then step through the MachineInstrs again collecting
the variable value transfer function. This simplifies things for the new
few patches.

Differential Revision: https://reviews.llvm.org/D85760
2020-10-23 11:13:20 +01:00
David Blaikie 4437df8eed DebugInfo: Hash DIE referevences (DW_OP_convert) when computing Split DWARF signatures 2020-10-22 20:09:33 -07:00
Han Shen e42f6c0ac0 Revert "[MBP] Add whole chain to BlockFilterSet instead of individual BB"
This reverts commit adfb541501.

This is reverted because it caused an chrome error: https://crbug.com/1140168
2020-10-22 17:31:01 -07:00
David Blaikie a66311277a DWARFv5: Disable DW_OP_convert for configurations that don't yet support it
Testing reveals that lldb and gdb have some problems with supporting
DW_OP_convert - gdb with Split DWARF tries to resolve the CU-relative
DIE offset relative to the skeleton DIE. lldb tries to treat the offset
as absolute, which judging by the llvm-dsymutil support for
DW_OP_convert, I guess works OK in MachO? (though probably llvm-dsymutil
is producing invalid DWARF by resolving the relative reference to an
absolute one?).

Specifically this disables DW_OP_convert usage in DWARFv5 if:
* Tuning for GDB and using Split DWARF
* Tuning for LLDB and not targeting MachO
2020-10-22 12:02:33 -07:00
Mircea Trofin e24537d48f [NFC][MC] Use MCRegister for ReachingDefAnalysis APIs
Also updated the users of the APIs; and a drive-by small change to
RDFRegister.cpp

Differential Revision: https://reviews.llvm.org/D89912
2020-10-22 08:47:35 -07:00
Jeremy Morse 68ac02c0dd [DebugInstrRef] Pass DBG_INSTR_REFs through register allocation
Both FastRegAlloc and LiveDebugVariables/greedy need to cope with
DBG_INSTR_REFs. None of them actually need to take any action, other than
passing DBG_INSTR_REFs through: variable location information doesn't refer
to any registers at this stage.

LiveDebugVariables stashes the instruction information in a tuple, then
re-creates it later. This is only necessary as the register allocator
doesn't expect to see any debug instructions while it's working. No
equivalence classes or interval splitting is required at all!

No changes are needed for the fast register allocator, as it just ignores
debug instructions. The test added checks that both of them preserve
DBG_INSTR_REFs.

This also expands ScheduleDAGInstrs.cpp to treat DBG_INSTR_REFs the same as
DBG_VALUEs when rescheduling instructions around. The current movement of
DBG_VALUEs around is less than ideal, but it's not a regression to make
DBG_INSTR_REFs subject to the same movement.

Differential Revision: https://reviews.llvm.org/D85757
2020-10-22 15:51:22 +01:00
Matt Arsenault 188df17420 ScheduleDAGInstrs: Skip debug instructions at end of scheduling region
If the end instruction of the scheduling region was a DBG_VALUE, the
uses of the debug instruction were tracked as if they were real
uses. This would then hit the deadDefHasNoUse assertion in
addVRegDefDeps if the only use was the debug instruction.
2020-10-22 10:16:45 -04:00
Jeremy Morse d73275993b [DebugInstrRef] Substitute debug value numbers to handle optimizations
This patch touches two optimizations, TwoAddressInstruction and X86's
FixupLEAs pass, both of which optimize by re-creating instructions. For
LEAs, various bits of arithmetic are better represented as LEAs on X86,
while TwoAddressInstruction sometimes converts instrs into three address
instructions if it's profitable.

For debug instruction referencing, both of these require substitutions to
be created -- the old instruction number must be pointed to the new
instruction number, as illustrated in the added test. If this isn't done,
any variable locations based on the optimized instruction are
conservatively dropped.

Differential Revision: https://reviews.llvm.org/D85756
2020-10-22 13:01:03 +01:00
Fangrui Song b0c12474ed [ShrinkWrap] Delete unneeded nullptr checks for the save point. NFC
findNearestCommonDominator never returns nullptr.
2020-10-22 00:27:01 -07:00
Xiang1 Zhang 7c3fea7721 [X86] Support customizing stack protector guard
Reviewed By: nickdesaulniers, MaskRay

Differential Revision: https://reviews.llvm.org/D88631
2020-10-22 10:08:14 +08:00
Craig Topper 9e884169a2 [FPEnv][X86][SystemZ] Use different algorithms for i64->double uint_to_fp under strictfp to avoid producing -0.0 when rounding toward negative infinity
Some of our conversion algorithms produce -0.0 when converting unsigned i64 to double when the rounding mode is round toward negative. This switches them to other algorithms that don't have this problem. Since it is undefined behavior to change rounding mode with the non-strict nodes, this patch only changes the behavior for strict nodes.

There are still problems with unsigned i32 conversions too which I'll try to fix in another patch.

Fixes part of PR47393

Reviewed By: efriedma

Differential Revision: https://reviews.llvm.org/D87115
2020-10-21 18:12:54 -07:00
Gaurav Jain 4634ad6c0b [NFC] Set return type of getStackPointerRegisterToSaveRestore to Register
Differential Revision: https://reviews.llvm.org/D89858
2020-10-21 16:19:38 -07:00
Jeremy Morse 537f0fbe82 [DebugInfo] Follow up c521e44def with an API improvement
As mentioned post-commit in D85749, the 'substituteDebugValuesForInst'
method added in c521e44def would be better off with a limit on the
number of operands to substitute. This handles the common case of
"substitute the first operand between these two differing instructions",
or possibly up to N first operands.
2020-10-21 14:45:55 +01:00
Simon Pilgrim 88523f6f4b [DAG] getNode(ISD::EXTRACT_SUBVECTOR) Drop unnecessary N2C null check - we assert that this isn't null and have already used the pointer. NFCI.
Fixes cppcheck + null dereference warning.
2020-10-21 11:53:44 +01:00
Nicholas Guy 9a2d2bedb7 Add "SkipDead" parameter to TargetInstrInfo::DefinesPredicate
Some instructions may be removable through processes such as IfConversion,
however DefinesPredicate can not be made aware of when this should be considered.
This parameter allows DefinesPredicate to distinguish these removable instructions
on a per-call basis, allowing for more fine-grained control from processes like
ifConversion.

Renames DefinesPredicate to ClobbersPredicate, to better reflect it's purpose

Differential Revision: https://reviews.llvm.org/D88494
2020-10-21 11:52:47 +01:00
Sven van Haastregt bfc961aeb2 [TargetLowering] Check boolean content when folding bit compare
Updates an optimization that relies on boolean contents being either 0
or 1 to properly check for this before triggering.

The following:
  (X & 8) != 0 --> (X & 8) >> 3
Produces unexpected results when a boolean 'true' value is represented
by negative one.

Patch by Erik Hogeman.

Differential Revision: https://reviews.llvm.org/D89390
2020-10-21 11:46:55 +01:00
David Sherwood 5b17b323a6 [SVE][CodeGen] Replace use of TypeSize comparison operator in CreateStackTemporary
We were previously relying upon the TypeSize comparison operators to
obtain the maximum size of two types, however use of such operators is
being deprecated in favour of making the caller aware that it could
be dealing with scalable vector types. I have changed the code to assert
that the two types have the same scalable property and thus we can
simply take the maximum of the known minimum sizes instead.

Differential Revision: https://reviews.llvm.org/D88563
2020-10-21 08:31:36 +01:00
Mircea Trofin 5e731625f3 [NFC][MC] Use [MC]Register in MachineVerifier
Differential Revision: https://reviews.llvm.org/D89815
2020-10-20 20:42:35 -07:00
Hubert Tong 134ffa8138 NFC: Fix -Wsign-compare warnings on 32-bit builds
Comparing 32-bit `ptrdiff_t` against 32-bit `unsigned` results in
`-Wsign-compare` warnings for both GCC and Clang.

The warning for the cases in question appear to identify an issue
where the `ptrdiff_t` value would be mutated via conversion to an
unsigned type.

The warning is resolved by using the usual arithmetic conversions to
safely preserve the value of the `unsigned` operand while trying to
convert to a signed type. Host platforms where `unsigned` has the same
width as `unsigned long long` will need to make a different change, but
using an explicit cast has disadvantages that can be avoided for now.

Reviewed By: dantrushin

Differential Revision: https://reviews.llvm.org/D89612
2020-10-20 20:52:10 -04:00
Austin Kerbow 37d907899f [HazardRec] Allow inserting multiple wait-states simultaneously
If a target can encode multiple wait-states into a noop allow emitting such
instructions directly.

Reviewed By: rampitec, dmgreen

Differential Revision: https://reviews.llvm.org/D89753
2020-10-20 17:03:47 -07:00
Nicolai Hähnle c0cdd22c72 Introduce CfgTraits abstraction
The CfgTraits abstraction simplfies writing algorithms that are
generic over the type of CFG, and enables writing such algorithms
as regular non-template code that operates on opaque references
to CFG blocks and values.

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

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

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

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

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

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

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

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

Change-Id: Ia75f4f268fded33fca11218a7d578c9aec1f3f4d

Differential Revision: https://reviews.llvm.org/D83088
2020-10-20 13:50:52 +02:00
Luqman Aden 51892a42da [COFF][ARM] Fix CodeView for Windows on 32bit ARM targets.
Create the LLVM / CodeView register mappings for the 32-bit ARM Window targets.

Reviewed By: compnerd

Differential Revision: https://reviews.llvm.org/D89622
2020-10-19 22:16:16 -07:00
Qiu Chaofan 1b2fe71ecf [DAGCombiner] Tighten reasscociation of visitFMA
From LangRef, FMF contract should not enable reassociating to form
arbitrary contractions. So it should not help rearrange nodes like
(fma (fmul x, c1), c2, y) into (fma x, c1*c2, y).

Reviewed By: spatel

Differential Revision: https://reviews.llvm.org/D89527
2020-10-20 10:13:01 +08:00
Craig Topper edd0cb11bd [SelectionDAG][X86] Enable SimplifySetCC CTPOP transforms for vector splats
This enables these transforms for vectors:
(ctpop x) u< 2 -> (x & x-1) == 0
(ctpop x) u> 1 -> (x & x-1) != 0
(ctpop x) == 1 --> (x != 0) && ((x & x-1) == 0)
(ctpop x) != 1 --> (x == 0) || ((x & x-1) != 0)

All enabled if CTPOP isn't Legal. This differs from the scalar
behavior where the first two are done unconditionally and the
last two are done if CTPOP isn't Legal or Custom. The Legal
check produced better results for vectors based on X86's
custom handling. Might be worth re-visiting scalars here.

I disabled the looking through truncate for vectors. The
code that creates new setcc can use the same result VT as the
original setcc even if we truncated the input. That may work
work for most scalars, but definitely wouldn't work for vectors
unless it was a vector of i1.

Fixes or at least improves PR47825

Reviewed By: spatel

Differential Revision: https://reviews.llvm.org/D89346
2020-10-19 12:56:59 -07:00
Amy Kwan 6a946fd06f [DAGCombiner][PowerPC] Remove isMulhCheaperThanMulShift TLI hook, Use isOperationLegalOrCustom directly instead.
MULH is often expanded on targets.
This patch removes the isMulhCheaperThanMulShift hook and uses
isOperationLegalOrCustom instead.

Differential Revision: https://reviews.llvm.org/D80485
2020-10-19 12:23:04 -05:00
Mircea Trofin 225065b9a8 [NFC][MC] Type [MC]Register uses in MachineTraceMetrics
Differential Revision: https://reviews.llvm.org/D89710
2020-10-19 09:49:52 -07:00
David Sherwood 3945b69e81 [SVE][CodeGen] Replace more TypeSize comparison operators with their scalar equivalents
In certain places in llvm/lib/CodeGen we were relying upon the TypeSize
comparison operators when in fact the code was only ever expecting
either scalar values or fixed width vectors. This patch changes a few
functions that were always expecting to work on scalar or fixed width
types:

1. DAGCombiner::mergeTruncStores - deals with scalar integers only.
2. DAGCombiner::ReduceLoadWidth - not valid for vectors.
3. DAGCombiner::createBuildVecShuffle - should only be used for
   fixed width vectors.
4. SelectionDAGLegalize::ExpandFCOPYSIGN and
   SelectionDAGLegalize::getSignAsIntValue - only work on scalars.

Differential Revision: https://reviews.llvm.org/D88562
2020-10-19 08:38:50 +01:00
David Sherwood 35a531fb45 [SVE][CodeGen][NFC] Replace TypeSize comparison operators with their scalar equivalents
In certain places in llvm/lib/CodeGen we were relying upon the TypeSize
comparison operators when in fact the code was only ever expecting
either scalar values or fixed width vectors. I've changed some of these
places to use the equivalent scalar operator.

Differential Revision: https://reviews.llvm.org/D88482
2020-10-19 08:30:31 +01:00
David Sherwood f693f915a0 [SVE][CodeGen] Replace uses of TypeSize comparison operators
In certain places in the code we can never end up in a situation where
we're mixing fixed width and scalable vector types. For example,
we can't have truncations and extends that change the lane count. Also,
in other places such as GenWidenVectorStores and GenWidenVectorLoads we
know from the behaviour of FindMemType that we can never choose a vector
type with a different scalable property.

In various places I have used EVT::bitsXY functions instead of
TypeSize::isKnownXY, where it probably makes sense to keep an assert
that scalable properties match.

Differential Revision: https://reviews.llvm.org/D88654
2020-10-19 08:08:41 +01:00
Alok Kumar Sharma 0538353b3b [DebugInfo] Support for DWARF operator DW_OP_over
LLVM rejects DWARF operator DW_OP_over. This DWARF operator is needed
for Flang to support assumed rank array.

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

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

Reviewed By: aprantl

Differential Revision: https://reviews.llvm.org/D89208
2020-10-17 08:42:28 +05:30
Craig Topper 278bd06891 [TargetLowering] Extract simplifySetCCs ctpop into a separate function. NFCI
As requested in D89346. This allows us to add some early outs.

I reordered some checks a little bit to make the more common bail outs happen earlier. Like checking opcode before checking hasOneUse. And I moved the bit width check to make sure it was safe to look through a truncate to the spot where we look through truncates instead of after.

Reviewed By: spatel

Differential Revision: https://reviews.llvm.org/D89494
2020-10-16 19:47:56 -07:00
Jameson Nash 4242df1470 Revert "make the AsmPrinterHandler array public"
I messed up one of the tests.
2020-10-16 17:22:07 -04:00
Jameson Nash ac2def2d8d make the AsmPrinterHandler array public
This lets external consumers customize the output, similar to how
AssemblyAnnotationWriter lets the caller define callbacks when printing
IR. The array of handlers already existed, this just cleans up the code
so that it can be exposed publically.

Differential Revision: https://reviews.llvm.org/D74158
2020-10-16 16:27:31 -04:00
Amara Emerson 6042c25b0a [GlobalISel] Add translation support for vector reduction intrinsics.
In order to prevent the ExpandReductions pass from expanding some intrinsics
before they get to codegen, I had to add a -disable-expand-reductions flag
for testing purposes.

Differential Revision: https://reviews.llvm.org/D89028
2020-10-16 10:17:53 -07:00
Jay Foad 0c1381d795 [llc] Use -filetype=null to disable MIR printing
If you use -stop-after or similar options, llc will normally print MIR.
This patch checks for -filetype=null as a special case to disable MIR
printing. As the comment says, "The Null output is intended for use for
performance analysis ...", and I found this useful for timing a subset
of the passes that llc runs without the significant overhead of printing
MIR just to send it to /dev/null.

Differential Revision: https://reviews.llvm.org/D89476
2020-10-16 16:51:56 +01:00
Amara Emerson c2551c1f40 [GlobalISel] Remove scalar src from non-sequential fadd/fmul reductions.
It's probably better to split these into separate G_FADD/G_FMUL + G_VECREDUCE
operations in the translator rather than carrying the scalar around. The
majority of the time it'll get simplified away as the scalars are probably
identity values.

Differential Revision: https://reviews.llvm.org/D89150
2020-10-15 15:51:44 -07:00
Denis Antrushin 8f0ddd4a1a [Statepoints] Remove MI limit on number of tied operands.
After D87915 statepoint can have more than 15 tied operands.
Remove this restriction from statepoint lowering code.
2020-10-15 19:02:38 +07:00
Adrian Kuegel ead2aa7098 Fix unused variable warning when compiling with asserts disabled.
Differential Revision: https://reviews.llvm.org/D89454
2020-10-15 12:50:19 +02:00
Jeremy Morse c521e44def [DebugInstrRef] Support recording of instruction reference substitutions
Add a table recording "substitutions" between pairs of <instruction,
operand> numbers, from old pairs to new pairs. Post-isel optimizations are
able to record the outcome of an optimization in this way. For example, if
there were a divide instruction that generated the quotient and remainder,
and it were replaced by one that only generated the quotient:

  $rax, $rcx = DIV-AND-REMAINDER $rdx, $rsi, debug-instr-num 1
  DBG_INSTR_REF 1, 0
  DBG_INSTR_REF 1, 1

Became:

  $rax = DIV $rdx, $rsi, debug-instr-num 2
  DBG_INSTR_REF 1, 0
  DBG_INSTR_REF 1, 1

We could enter a substitution from <1, 0> to <2, 0>, and no substitution
for <1, 1> as it's no longer generated.

This approach means that if an instruction or value is deleted once we've
left SSA form, all variables that used the value implicitly become
"optimized out", something that isn't true of the current DBG_VALUE
approach.

Differential Revision: https://reviews.llvm.org/D85749
2020-10-15 11:30:14 +01:00
Denis Antrushin 8c2b69d53a [Statepoints] Unlimited tied operands.
Current limit on amount of tied operands (15) sometimes is too low
for statepoint. We may get couple dozens of gc pointer operands on
statepoint.
Review D87154 changed format of statepoint to list every gc pointer
only once, which makes it trivial to find tiedness relation between
statepoint operands: defs are mapped 1-1 to gc pointer operands passed
on registers.

Reviewed By: skatkov

Differential Revision: https://reviews.llvm.org/D87915
2020-10-15 16:16:11 +07:00
Craig Topper 50c9f1e11d [TargetLowering] Replace Log2_32_Ceil with Log2_32 in SimplifySetCC ctpop combine.
This combine can look through (trunc (ctpop X)). When doing this
it tries to make sure the trunc doesn't lose any information
from the ctpop. It does this by checking that the truncated type
has more bits that Log2_32_Ceil of the ctpop type. The Ceil is
unnecessary and pessimizes non-power of 2 types.

For example, ctpop of i256 requires 9 bits to represent the max
value of 256. But ctpop of i255 only requires 8 bits to represent
the max result of 255. Log2_32_Ceil of 256 and 255 both return 8
while Log2_32 returns 8 for 256 and 7 for 255

The code with popcnt enabled is a regression for this test case,
but it does match what already happens with i256 truncated to i9.
Since power of 2 is more likely, I don't think it should block
this change.

Differential Revision: https://reviews.llvm.org/D89412
2020-10-15 01:05:07 -07:00
Snehasish Kumar 24bf6ff4e0 [llvm] Update default cutoff threshold for machine function splitter.
Based on internal testing at Google we found that setting the profile
summary cutoff threshold to 999950 yields the best results in terms of
itlb and icache metrics (as observed on Intel CPUs).

*default* = Split out code if no profile count available for block
*size-%*  = The fraction of bytes split out of .text and .text.hot
*itlb*    = Misses per kilo instructions (MPKI) for itlb
*icache*  = Misses per kilo instructions (MPKI) for L1 icache

Search1

| cutoff  | size-%  | itlb      | icache  |
|---------|---------|-----------|---------|
| default | 42.5861 | 0.0822151 | 2.46363 |
|  999999 | 44.9350 | 0.0767194 | 2.44416 |
|  999950 | 50.0660 |  0.075744 |  2.4091 |
|  999500 | 56.9158 |  0.082564 |  2.4188 |
|  995000 | 63.8625 | 0.0814927 | 2.42832 |
|  990000 | 71.7314 |  0.106906 | 2.57785 |

Search2

| cutoff  | size-% | itlb     | icache  |
|---------|--------|----------|---------|
| default | 2.8845 | 0.626712 | 4.73245 |
|  999999 | 3.3291 | 0.602309 | 4.70045 |
|  999950 | 3.8577 | 0.587842 | 4.71632 |
|  999500 | 4.4170 |  0.63577 | 4.68351 |
|  995000 | 5.1020 | 0.657969 | 4.82272 |
|  990000 | 5.7153 | 0.719122 | 5.39496 |

Differential Revision: https://reviews.llvm.org/D89085
2020-10-14 12:48:10 -07:00
Snehasish Kumar 77638a5343 [llvm] Set the default for -bbsections-cold-text-prefix to .text.split.
After using this for a while, we find that it is generally useful to
have it set to .text.split. by default, removing the need for an
additional -mllvm option.

Differential Revision: https://reviews.llvm.org/D88997
2020-10-14 12:16:36 -07:00
Guozhi Wei adfb541501 [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
2020-10-14 11:55:10 -07:00
jasonliu f85bcc21dd [AIX] Turn -fdata-sections on by default in Clang
Summary:

This patch does the following:
1. Make InitTargetOptionsFromCodeGenFlags() accepts Triple as a
 parameter, because some options' default value is triple dependant.
2. DataSections is turned on by default on AIX for llc.
3. Test cases change accordingly because of the default behaviour change.
4. Clang Driver passes in -fdata-sections by default on AIX.

Reviewed By: MaskRay, DiggerLin

Differential Revision: https://reviews.llvm.org/D88737
2020-10-14 15:58:31 +00:00
Mircea Trofin c8fcffe775 [NFC][MC] Use MCRegister in Machine{Sink|Pipeliner}.cpp
Differential Revision: https://reviews.llvm.org/D89328
2020-10-14 08:42:17 -07:00
Michael Liao ae40d2858e Fix an apparent typo. `assert()` must not contain side-effects. NFC. 2020-10-14 11:33:34 -04:00
Jeremy Morse c4e7857d4e [DebugInstrRef] Create DBG_INSTR_REFs in SelectionDAG
When given the -experimental-debug-variable-locations option (via -Xclang
or to llc), have SelectionDAG generate DBG_INSTR_REF instructions instead
of DBG_VALUE. For now, this only happens in a limited circumstance: when
the value referred to is not a PHI and is defined in the current block.
Other situations introduce interesting problems, addresed in later patches.

Practically, this patch hooks into InstrEmitter and if it can find a
defining instruction for a value, gives it an instruction number, and
points the DBG_INSTR_REF at that <instr, operand> pair.

Differential Revision: https://reviews.llvm.org/D85747
2020-10-14 14:24:08 +01:00
Jeremy Morse 2c5f3d54c5 [DebugInstrRef] Parse debug instruction-references from/to MIR
This patch defines the MIR format for debug instruction references: it's an
integer trailing an instruction, marked out by "debug-instr-number", much
like how "debug-location" identifies the DebugLoc metadata of an
instruction. The instruction number is stored directly in a MachineInstr.

Actually referring to an instruction comes in a later patch, but is done
using one of these instruction numbers.

I've added a round-trip test and two verifier checks: that we don't label
meta-instructions as generating values, and that there are no duplicates.

Differential Revision: https://reviews.llvm.org/D85746
2020-10-14 10:57:09 +01:00
Aditya Nandakumar ef3d17482f [GISel] Add combine for constant G_PTR_ADD offsets.
https://reviews.llvm.org/D88865

This adds a single combine for GlobalISel to fold:

ptradd (inttoptr C1) C2
Into:

C1 + C2
Additionally, a small test for AArch64 is added.

Patch by pnappa.
2020-10-13 17:26:12 -07:00
Andrew Paverd cfd8481da1 Reland [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
2020-10-13 13:20:52 -07:00