Summary: This patch introduces a new heuristic for guiding operand reordering. The new "look-ahead" heuristic can look beyond the immediate predecessors. This helps break ties when the immediate predecessors have identical opcodes (see lit test for an example).
Sanjay Patel [Wed, 26 Jun 2019 21:19:31 +0000 (21:19 +0000)]
[InstCombine] change 'tmp' variable names; NFC
I don't think there was anything going wrong here,
but the auto-generating CHECK line script is known
to have problems with 'TMP' because it uses that
to match nameless values.
Matt Arsenault [Wed, 26 Jun 2019 20:35:18 +0000 (20:35 +0000)]
[AMDGPU] Fix Livereg computation during epilogue insertion
The LivePhysRegs calculated in order to find a scratch register in the
epilogue code wrongly uses 'LiveIns'. Instead, it should use the
'Liveout' sets. For the liveness, also considering the operands of
the terminator (return) instruction which is the insertion point for
the scratch-exec-copy instruction.
Craig Topper [Wed, 26 Jun 2019 20:16:19 +0000 (20:16 +0000)]
[X86] Rework the logic in LowerBuildVectorv16i8 to make better use of any_extend and break false dependencies. Other improvements
This patch rewrites the loop iteration to only visit every other element starting with element 0. And we work on the "even" element and "next" element at the same time. The "First" logic has been moved to the bottom of the loop and doesn't run on every element. I believe it could create dangling nodes previously since we didn't check if we were going to use SCALAR_TO_VECTOR for the first insertion. I got rid of the "First" variable and just do a null check on V which should be equivalent. We also no longer use undef as the starting V for vectors with no zeroes to avoid false dependencies. This matches v8i16.
I've changed all the extends and OR operations to use MVT::i32 since that's what they'll be promoted to anyway. I've tried to use zero_extend only when necessary and use any_extend otherwise. This resulted in some improvements in tests where we are now able to promote aligned (i32 (extload i8)) to a 32-bit load.
JF Bastien [Wed, 26 Jun 2019 19:50:12 +0000 (19:50 +0000)]
BitStream reader: propagate errors
The bitstream reader handles errors poorly. This has two effects:
* Bugs in file handling (especially modules) manifest as an "unexpected end of
file" crash
* Users of clang as a library end up aborting because the code unconditionally
calls `report_fatal_error`
The bitstream reader should be more resilient and return Expected / Error as
soon as an error is encountered, not way late like it does now. This patch
starts doing so and adopting the error handling where I think it makes sense.
There's plenty more to do: this patch propagates errors to be minimally useful,
and follow-ups will propagate them further and improve diagnostics.
Craig Topper [Wed, 26 Jun 2019 19:45:48 +0000 (19:45 +0000)]
[X86] Remove isTypePromotionOfi1ZeroUpBits and its helpers.
This was trying to optimize concat_vectors with zero of setcc or
kand instructions. But I think it produced the same code we
produce for a concat_vectors with 0 even it it doesn't come from
one of those operations.
Simon Pilgrim [Wed, 26 Jun 2019 18:21:26 +0000 (18:21 +0000)]
[X86][SSE] getFauxShuffleMask - handle OR(x,y) where x and y have no overlapping bits
Create a per-byte shuffle mask based on the computeKnownBits from each operand - if for each byte we have a known zero (or both) then it can be safely blended.
Sanjay Patel [Wed, 26 Jun 2019 17:43:30 +0000 (17:43 +0000)]
[InstCombine] change 'tmp' variable names; NFC
I don't think there was anything going wrong here,
but the auto-generating CHECK line script is known
to have problems with 'TMP' because it uses that
to match nameless values.
Ryan Taylor [Wed, 26 Jun 2019 17:34:57 +0000 (17:34 +0000)]
[AMDGPU] Fix for branch offset hardware workaround
Summary:
This fixes a hardware bug that makes a branch offset of 0x3f unsafe.
This replaces the 32 bit branch with offset 0x3f to a 64 bit
instruction that includes the same 32 bit branch and the encoding
for a s_nop 0 to follow. The relaxer than modifies the offsets
accordingly.
Ulrich Weigand [Wed, 26 Jun 2019 17:19:12 +0000 (17:19 +0000)]
Allow matching extend-from-memory with strict FP nodes
This implements a small enhancement to https://reviews.llvm.org/D55506
Specifically, while we were able to match strict FP nodes for
floating-point extend operations with a register as source, this
did not work for operations with memory as source.
That is because from regular operations, this is represented as
a combined "extload" node (which is a variant of a load SD node);
but there is no equivalent using a strict FP operation.
However, it turns out that even in the absence of an extload
node, we can still just match the operations explicitly, e.g.
(strict_fpextend (f32 (load node:$ptr))
This patch implements that method to match the LDEB/LXEB/LXDB
SystemZ instructions even when the extend uses a strict-FP node.
Thomas Lively [Wed, 26 Jun 2019 16:19:59 +0000 (16:19 +0000)]
[WebAssembly] Omit wrap on i64x2.{shl,shr*} ISel when possible
Summary:
Since the WebAssembly SIMD shift instructions take i32 operands, we
truncate the i64 operand to <2 x i64> shifts during ISel. When the i64
operand is sign extended from i32, this CL makes it so the sign
extension is dropped instead of a wrap instruction added.
Thomas Lively [Wed, 26 Jun 2019 16:17:15 +0000 (16:17 +0000)]
[WebAssembly] Implement tail calls and unify tablegen call classes
Summary:
Implements direct and indirect tail calls enabled by the 'tail-call'
feature in both DAG ISel and FastISel. Updates existing call tests and
adds new tests including a binary encoding test.
Greg Clayton [Wed, 26 Jun 2019 14:09:09 +0000 (14:09 +0000)]
Add GSYM utility files along with unit tests.
The full GSYM patch started with: https://reviews.llvm.org/D53379
In that patch we wanted to split up getting GSYM into the LLVM code base so we are not committing too much code at once.
This is a first in a series of patches where I only add the foundation classes along with complete unit tests. They provide the foundation for encoding and decoding a GSYM file.
File entries are defined in llvm::gsym::FileEntry. This class splits the file up into a directory and filename represented by uniqued string table offsets. This allows all files that are referred to in a GSYM file to be encoded as 1 based indexes into a global file table in the GSYM file.
Function information in stored in llvm::gsym::FunctionInfo. This object represents a contiguous address range that has a name and range with an optional line table and inline call stack information.
Line table entries are defined in llvm::gsym::LineEntry. They store only address, file and line information to keep the line tables simple and allows the information to be efficiently encoded in a subsequent patch.
Inline information is defined in llvm::gsym::InlineInfo. These structs store the name of the inline function, along with one or more address ranges, and the file and line that called this function. They also contain any child inline information.
There are also utility classes for address ranges in llvm::gsym::AddressRange, and string table support in llvm::gsym::StringTable which are simple classes.
The unit tests test all the APIs on these simple classes so they will be ready for the next patches where we will create GSYM files and parse GSYM files.
Fedor Sergeev [Wed, 26 Jun 2019 13:24:24 +0000 (13:24 +0000)]
[InlineCost] cleanup calculations of Cost and Threshold
Summary:
Doing better separation of Cost and Threshold.
Cost counts the abstract complexity of live instructions, while Threshold is an upper bound of complexity that inlining is comfortable to pay.
There are two parts:
- huge 15K last-call-to-static bonus is no longer subtracted from Cost
but rather is now added to Threshold.
That makes much more sense, as the cost of inlining (Cost) is not changed by the fact
that internal function is called once. It only changes the likelyhood of this inlining
being profitable (Threshold).
- bonus for calls proved-to-be-inlinable into callee is no longer subtracted from Cost
but added to Threshold instead.
While calculations are somewhat different, overall InlineResult should stay the same since Cost >= Threshold compares the same.
Summary:
The one thing of note here is that the 'bitwidth' constant (32/64) was previously pessimistic.
Given `x & (-1 >> (C - z))`, we were taking `C` to be `bitwidth(x)`, but in reality
we want `(-1 >> (C - z))` pattern to mean "low z bits must be all-ones".
And for that, `C` should be `bitwidth(-1 >> (C - z))`, i.e. of the shift operation itself.
Last pattern D does not seem to exhibit any of these truncation issues.
Although it has the opposite problem - if we extract low bits (no shift) from i64,
and then truncate to i32, then we fail to shrink this 64-bit extraction into 32-bit extraction.
The problem is quite simple:
If we have pattern `(x >> start) & (1 << nbits) - 1`,
and then truncate the result, that truncation will be propagated upwards,
into the `and`. And that isn't currently handled.
I'm only fixing pattern `a` here,
the same fix will be needed for patterns `b`/`c` too.
I *think* this isn't missing any extra legality checks,
since we only look past truncations. Similary, i don't think
we can get any other truncation there other than i64->i32.
As detailed in https://bugs.llvm.org/show_bug.cgi?id=42253, there were a
number of issues in the llvm-symbolizer documentation. This patch fixes
them by:
1. Adding [addresses...] to the synopsis, and matching the formatting
of other tools.
2. Rewriting the description to fix grammar issues and mention other
usage options.
3. Rewriting the examples to be easier to read.
4. Re-ordering the options into alphabetical order.
5. Improving the text of some of the option descriptions, and adding
some examples to individual options.
6. Splitting the Mach-O options into a separate section of the
document.
7. Standardizing on double dashes for long options throughout the file.
8. Adding a reference to the llvm-addr2line document.
Simon Pilgrim [Wed, 26 Jun 2019 11:21:09 +0000 (11:21 +0000)]
[X86][AVX] combineExtractSubvector - 'little to big' extract_subvector(bitcast()) support
Ideally this needs to be a generic combine in DAGCombiner::visitEXTRACT_SUBVECTOR but there's some nasty regressions in aarch64 due to neon shuffles not handling bitcasts at all.....
[IR/DIVar] Add the flag for params that have unmodified value
Introduce the debug info flag that indicates that a parameter has unchanged
value throughout a function. This info will be used to emit the expressions
with DW_OP_entry_value.
([4/13] Introduce the debug entry values.)
Co-authored-by: Ananth Sowda <asowda@cisco.com> Co-authored-by: Nikola Prica <nikola.prica@rt-rk.com> Co-authored-by: Ivan Baev <ibaev@cisco.com>
Differential Revision: https://reviews.llvm.org/D58034
Mikhail Maltsev [Wed, 26 Jun 2019 10:48:40 +0000 (10:48 +0000)]
[ARM] Handle fixup_arm_pcrel_9 correctly on big-endian targets
Summary:
The getFixupKindContainerSizeBytes function returns the size of the
instruction containing a given fixup. Currently fixup_arm_pcrel_9 is
not handled in this function, this causes an assertion failure in
the debug build and incorrect codegen in the release build.
Lewis Revill [Wed, 26 Jun 2019 10:35:58 +0000 (10:35 +0000)]
[RISCV] Add pseudo instruction for calls with explicit register
This patch adds the PseudoCALLReg instruction which allows using an
explicit register operand as the destination for the return address.
GCC can successfully parse this form of the call instruction, which
would be used for calls to functions which do not use ra as the return
address register, such as the __riscv_save libcalls. This patch forms
the first part of an implementation of -msave-restore for RISC-V.
truncateVectorWithPACK is often used in conjunction with ComputeNumSignBits which struggles when peeking through bitcasts.
This fix tries to avoid bitcast(shuffle(bitcast())) patterns in the 256-bit 64-bit sublane shuffles so we can still see through at least until lowering when the shuffles will need to be bitcasted to widen the shuffle type.
Florian Hahn [Wed, 26 Jun 2019 09:16:57 +0000 (09:16 +0000)]
[LoopUnroll] Add support for loops with exiting headers and uncond latches.
This patch generalizes the UnrollLoop utility to support loops that exit
from the header instead of the latch. Usually, LoopRotate would take care
of must of those cases, but in some cases (e.g. -Oz), LoopRotate does
not kick in.
Codesize impact looks relatively neutral on ARM64 with -Oz + LTO.
[Metadata] Add GNU extensions for call site DWARF symbols
As discussed on RFC
(http://lists.llvm.org/pipermail/llvm-dev/2019-February/130094.html), this
is set of patches that introduces debug information about call site and
call site parameters. Since the LLVM has portion of this support (dumping
DWARF 5 symbols for calls), we generate GNU extensions as well. All of that
will be restricted under an option.
([1/13] Introduce the debug entry values.)
Co-authored-by: Ananth Sowda <asowda@cisco.com> Co-authored-by: Nikola Prica <nikola.prica@rt-rk.com> Co-authored-by: Ivan Baev <ibaev@cisco.com>
Differential Revision: https://reviews.llvm.org/D60712
QingShan Zhang [Wed, 26 Jun 2019 05:12:53 +0000 (05:12 +0000)]
Teach the DAGCombine to fold this pattern(c1 and c2 is constant).
// fold (sext (select cond, c1, c2)) -> (select cond, sext c1, sext c2)
// fold (zext (select cond, c1, c2)) -> (select cond, zext c1, zext c2)
// fold (aext (select cond, c1, c2)) -> (select cond, sext c1, sext c2)
Sign extend the operands if it is any_extend, to keep the signess of the operands that, the other combine rule would apply. The any_extend is handled as zero extend for constants. i.e.
This change causes some llvm-obcopy tests to fail with valgrind.
Following is the output for basic-keep.test
Command Output (stderr):
--
==107406== Conditional jump or move depends on uninitialised value(s)
==107406== at 0x1A30DD: executeObjcopy(llvm::objcopy::CopyConfig const&) (llvm-objcopy.cpp:235)
==107406== by 0x1A3935: main (llvm-objcopy.cpp:294)
Nemanja Ivanovic [Wed, 26 Jun 2019 02:46:03 +0000 (02:46 +0000)]
[NFC] Fix buildbot breaks due to r364375
For some reason, the update_llc_checks.py script produces checks for
empty lines which cause failures. Corrected that to check for actual
text produced by llc.
Nemanja Ivanovic [Wed, 26 Jun 2019 02:01:11 +0000 (02:01 +0000)]
[PowerPC][NFC] Add a TOC save test case prior to posting a related patch
An upcoming patch will modify the behaviour with respect to saving the TOC
in functions with indirect calls.
Adding a test case so the patch will show the difference in codegen.
Nemanja Ivanovic [Wed, 26 Jun 2019 01:48:57 +0000 (01:48 +0000)]
[PowerPC] Mark FCOPYSIGN legal for FP vectors
This was just an omission in the back end. We have had the instructions for both
single and double precision for a few HW generations, but never got around to
legalizing these.
The weak alias should have the characteristics set to
`IMAGE_EXTERN_WEAK_SEARCH_ALIAS` to indicate that the weak external here
is a symbol alias and that the symbol is aliased to a locally defined
symbol. We were previously setting the characteristics to
`IMAGE_EXTERN_WEAK_SEARCH_LIBRARY` which indicates that the symbol
should be looked for in the libraries.
Keno Fischer [Wed, 26 Jun 2019 00:52:42 +0000 (00:52 +0000)]
[WebAssembly] Fix list of relocations with addends in lld
Summary:
The list of relocations with addend in lld was missing `R_WASM_MEMORY_ADDR_REL_SLEB`,
causing `wasm-ld` to generate corrupted output. This fixes that problem and while
we're at it pulls the list of such relocations into the Wasm.h header, to avoid
duplicating it in multiple places.
Erich Keane [Wed, 26 Jun 2019 00:08:22 +0000 (00:08 +0000)]
Teach TableGen Intrin Emitter to handle LLVMPointerType<llvm_any_ty>
r363233 rewrote a bunch of the Intrin Emitter code, however the new
function to update the arg codes did not properly consider a pointer to
an any. This patch adds that logic.
Heejin Ahn [Tue, 25 Jun 2019 23:04:12 +0000 (23:04 +0000)]
[WebAssembly] Remove catch_all from AsmParser
Summary:
`catch_all` is from the first version of EH proposal and now has been
removed. There were no tests covering this, and thus no tests to remove
or fix.
When we calculate MII, we use two loops, one with iterator R++ to
check whether we can reserve the resource, then --R to move back
the iterator to do reservation.
This is risky, as R++, --R may not point to the same element at all.
The can cause wrong MII.
Diego Novillo [Tue, 25 Jun 2019 18:55:16 +0000 (18:55 +0000)]
Update phis in AMDGPUUnifyDivergentExitNodes
Original patch https://reviews.llvm.org/D63659 from
Steven Perron <stevenperron@google.com>
The pass AMDGPUUnifyDivergentExitNodes does not update the phi nodes in
the successors of blocks that is splits. This is fixed by calling
BasicBlock::splitBasicBlock to split the block instead of doing it
manually. This does extra work because a new conditional branch is
created in BB which is immediately replaced, but I think the simplicity
is worth it. It also helps make the code more future proof in case other
things need to be updated.
Craig Topper [Tue, 25 Jun 2019 17:31:52 +0000 (17:31 +0000)]
[X86] Remove isel patterns that look for (vzext_movl (scalar_to_vector (load)))
I believe these all get canonicalized to vzext_movl. The only case where that wasn't true was when the load was loadi32 and the load was an extload aligned to 32 bits. But that was fixed in r364207.
Philip Reames [Tue, 25 Jun 2019 17:29:18 +0000 (17:29 +0000)]
[Peephole] Allow folding loads into instructions w/multiple uses (such as test64rr)
Peephole opt has a one use limitation which appears to be accidental. The function being used was incorrectly documented as returning whether the def had one *user*, but instead returned true only when there was one *use*. Add a corresponding hasOneNonDbgUser helper, and adjust peephole-opt to use the appropriate one.
All of the actual folding code handles multiple uses within a single instruction. That codepath is well exercised through instruction selection.
Craig Topper [Tue, 25 Jun 2019 17:08:26 +0000 (17:08 +0000)]
[X86] Add a DAG combine to turn vzmovl+load into vzload if the load isn't volatile. Remove isel patterns for vzmovl+load
We currently have some isel patterns for treating vzmovl+load the same as vzload, but that shrinks the load which we shouldn't do if the load is volatile.
Rather than adding isel checks for volatile. This patch removes the patterns and teachs DAG combine to merge them into vzload when its legal to do so.
Simon Tatham [Tue, 25 Jun 2019 16:49:32 +0000 (16:49 +0000)]
[ARM] Support inline assembler constraints for MVE.
"To" selects an odd-numbered GPR, and "Te" an even one. There are some
8.1-M instructions that have one too few bits in their register fields
and require registers of particular parity, without necessarily using
a consecutive even/odd pair.
Also, the constraint letter "t" should select an MVE q-register, when
MVE is present. This didn't need any source changes, but some extra
tests have been added.
Simon Tatham [Tue, 25 Jun 2019 16:48:46 +0000 (16:48 +0000)]
[ARM] Code-generation infrastructure for MVE.
This provides the low-level support to start using MVE vector types in
LLVM IR, loading and storing them, passing them to __asm__ statements
containing hand-written MVE vector instructions, and *if* you have the
hard-float ABI turned on, using them as function parameters.
(In the soft-float ABI, vector types are passed in integer registers,
and combining all those 32-bit integers into a q-reg requires support
for selection DAG nodes like insert_vector_elt and build_vector which
aren't implemented yet for MVE. In fact I've also had to add
`arm_aapcs_vfpcc` to a couple of existing tests to avoid that
problem.)
Specifically, this commit adds support for:
* spills, reloads and register moves for MVE vector registers
* ditto for the VPT predication mask that lives in VPR.P0
* make all the MVE vector types legal in ISel, and provide selection
DAG patterns for BITCAST, LOAD and STORE
* make loads and stores of scalar FP types conditional on
`hasFPRegs()` rather than `hasVFP2Base()`. As a result a few
existing tests needed their llc command lines updating to use
`-mattr=-fpregs` as their method of turning off all hardware FP
support.
Fangrui Song [Tue, 25 Jun 2019 15:56:32 +0000 (15:56 +0000)]
[PPC32] Support PLT calls for -msecure-plt -fpic
Summary:
In Secure PLT ABI, -fpic is similar to -fPIC. The differences are that:
* -fpic stores the address of _GLOBAL_OFFSET_TABLE_ in r30, while -fPIC stores .got2+0x8000.
* -fpic uses an addend of 0 for R_PPC_PLTREL24, while -fPIC uses 0x8000.
Sam Parker [Tue, 25 Jun 2019 15:11:17 +0000 (15:11 +0000)]
[ARM] Fix for DLS/LE CodeGen
The expensive buildbots highlighted the mir tests were broken, which
I've now updated and added --verify-machineinstrs to them. This also
uncovered a couple of bugs in the backend pass, so these have also
been fixed.
Xing Xue [Tue, 25 Jun 2019 15:08:28 +0000 (15:08 +0000)]
Improve zero-size allocation with safe_malloc, etc.
Summary:
The current implementations of the memory allocation functions mistake a nullptr returned from std::malloc, std::calloc, or std::realloc as a failure. The behaviour for each of std::malloc, std::calloc, and std::realloc when the size is 0 is implementation defined (ISO/IEC 9899:2018 7.22.3), and may return a nullptr.
This patch checks if space requested is zero when a nullptr is returned, retry requesting non-zero if it is.