Commit Graph

1861 Commits

Author SHA1 Message Date
Francis Visoiu Mistrih a8a83d150f [CodeGen] Use MachineOperand::print in the MIRPrinter for MO_Register.
Work towards the unification of MIR and debug output by refactoring the
interfaces.

For MachineOperand::print, keep a simple version that can be easily called
from `dump()`, and a more complex one which will be called from both the
MIRPrinter and MachineInstr::print.

Add extra checks inside MachineOperand for detached operands (operands
with getParent() == nullptr).

https://reviews.llvm.org/D40836

* find . \( -name "*.mir" -o -name "*.cpp" -o -name "*.h" -o -name "*.ll" -o -name "*.s" \) -type f -print0 | xargs -0 sed -i '' -E 's/kill: ([^ ]+) ([^ ]+)<def> ([^ ]+)/kill: \1 def \2 \3/g'
* find . \( -name "*.mir" -o -name "*.cpp" -o -name "*.h" -o -name "*.ll" -o -name "*.s" \) -type f -print0 | xargs -0 sed -i '' -E 's/kill: ([^ ]+) ([^ ]+) ([^ ]+)<def>/kill: \1 \2 def \3/g'
* find . \( -name "*.mir" -o -name "*.cpp" -o -name "*.h" -o -name "*.ll" -o -name "*.s" \) -type f -print0 | xargs -0 sed -i '' -E 's/kill: def ([^ ]+) ([^ ]+) ([^ ]+)<def>/kill: def \1 \2 def \3/g'
* find . \( -name "*.mir" -o -name "*.cpp" -o -name "*.h" -o -name "*.ll" -o -name "*.s" \) -type f -print0 | xargs -0 sed -i '' -E 's/<def>//g'
* find . \( -name "*.mir" -o -name "*.cpp" -o -name "*.h" -o -name "*.ll" -o -name "*.s" \) -type f -print0 | xargs -0 sed -i '' -E 's/([^ ]+)<kill>/killed \1/g'
* find . \( -name "*.mir" -o -name "*.cpp" -o -name "*.h" -o -name "*.ll" -o -name "*.s" \) -type f -print0 | xargs -0 sed -i '' -E 's/([^ ]+)<imp-use,kill>/implicit killed \1/g'
* find . \( -name "*.mir" -o -name "*.cpp" -o -name "*.h" -o -name "*.ll" -o -name "*.s" \) -type f -print0 | xargs -0 sed -i '' -E 's/([^ ]+)<dead>/dead \1/g'
* find . \( -name "*.mir" -o -name "*.cpp" -o -name "*.h" -o -name "*.ll" -o -name "*.s" \) -type f -print0 | xargs -0 sed -i '' -E 's/([^ ]+)<def[ ]*,[ ]*dead>/dead \1/g'
* find . \( -name "*.mir" -o -name "*.cpp" -o -name "*.h" -o -name "*.ll" -o -name "*.s" \) -type f -print0 | xargs -0 sed -i '' -E 's/([^ ]+)<imp-def[ ]*,[ ]*dead>/implicit-def dead \1/g'
* find . \( -name "*.mir" -o -name "*.cpp" -o -name "*.h" -o -name "*.ll" -o -name "*.s" \) -type f -print0 | xargs -0 sed -i '' -E 's/([^ ]+)<imp-def>/implicit-def \1/g'
* find . \( -name "*.mir" -o -name "*.cpp" -o -name "*.h" -o -name "*.ll" -o -name "*.s" \) -type f -print0 | xargs -0 sed -i '' -E 's/([^ ]+)<imp-use>/implicit \1/g'
* find . \( -name "*.mir" -o -name "*.cpp" -o -name "*.h" -o -name "*.ll" -o -name "*.s" \) -type f -print0 | xargs -0 sed -i '' -E 's/([^ ]+)<internal>/internal \1/g'
* find . \( -name "*.mir" -o -name "*.cpp" -o -name "*.h" -o -name "*.ll" -o -name "*.s" \) -type f -print0 | xargs -0 sed -i '' -E 's/([^ ]+)<undef>/undef \1/g'

llvm-svn: 320022
2017-12-07 10:40:31 +00:00
Florian Hahn 5d6a4e43ba [AArch64] Add patterns to replace fsub fmul with fma fneg.
Summary:
This patch adds MachineCombiner patterns for transforming
(fsub (fmul x y) z) into (fma x y (fneg z)). This has a lower
latency on micro architectures where fneg is cheap.

Patch based on work by George Steed.

Reviewers: rengolin, joelkevinjones, joel_k_jones, evandro, efriedma

Reviewed By: evandro

Subscribers: aemerson, javed.absar, llvm-commits, kristof.beyls

Differential Revision: https://reviews.llvm.org/D40306

llvm-svn: 319980
2017-12-06 22:48:36 +00:00
Nirav Dave 7d8f3e0c93 [ARM][AArch64][DAG] Reenable post-legalize store merge
Reenable post-legalize stores with constant merging computation and
corresponding test case.

 * Properly truncate store merge constants
 * Disable merging of truncated stores floating points
 * Ensure merges of constant stores into a single vector are
   constructed from legal elements.

Reviewers: eastig, efriedma

Reviewed By: eastig

Subscribers: spatel, rengolin, aemerson, javed.absar, kristof.beyls, hiraditya, llvm-commits

Differential Revision: https://reviews.llvm.org/D40701

llvm-svn: 319899
2017-12-06 15:30:13 +00:00
Daniel Sanders 3c1c4c0ee0 Revert r319691: [globalisel][tablegen] Split atomic load/store into separate opcode and enable for AArch64.
Some concerns were raised with the direction. Revert while we discuss it and look into an alternative

llvm-svn: 319739
2017-12-05 05:52:07 +00:00
Daniel Sanders c83977fc21 [globalisel][tablegen] Tests for r319691
I forgot to 'svn add' the test files.

llvm-svn: 319698
2017-12-04 21:14:34 +00:00
Daniel Sanders 04e4f47e93 [globalisel][tablegen] Split atomic load/store into separate opcode and enable for AArch64.
This patch splits atomics out of the generic G_LOAD/G_STORE and into their own
G_ATOMIC_LOAD/G_ATOMIC_STORE. This is a pragmatic decision rather than a
necessary one. Atomic load/store has little in implementation in common with
non-atomic load/store. They tend to be handled very differently throughout the
backend. It also has the nice side-effect of slightly improving the common-case
performance at ISel since there's no longer a need for an atomicity check in the
matcher table.

All targets have been updated to remove the atomic load/store check from the
G_LOAD/G_STORE path. AArch64 has also been updated to mark
G_ATOMIC_LOAD/G_ATOMIC_STORE legal.

There is one issue with this patch though which also affects the extending loads
and truncating stores. The rules only match when an appropriate G_ANYEXT is
present in the MIR. For example,
  (G_ATOMIC_STORE (G_TRUNC:s16 (G_ANYEXT:s32 (G_ATOMIC_LOAD:s16 X))))
will match but:
  (G_ATOMIC_STORE (G_ATOMIC_LOAD:s16 X))
will not. This shouldn't be a problem at the moment, but as we get better at
eliminating extends/truncates we'll likely start failing to match in some
cases. The current plan is to fix this in a patch that changes the
representation of extending-load/truncating-store to allow the MMO to describe
a different type to the operation.

llvm-svn: 319691
2017-12-04 20:39:32 +00:00
Francis Visoiu Mistrih 25528d6de7 [CodeGen] Unify MBB reference format in both MIR and debug output
As part of the unification of the debug format and the MIR format, print
MBB references as '%bb.5'.

The MIR printer prints the IR name of a MBB only for block definitions.

* find . \( -name "*.mir" -o -name "*.cpp" -o -name "*.h" -o -name "*.ll" \) -type f -print0 | xargs -0 sed -i '' -E 's/BB#" << ([a-zA-Z0-9_]+)->getNumber\(\)/" << printMBBReference(*\1)/g'
* find . \( -name "*.mir" -o -name "*.cpp" -o -name "*.h" -o -name "*.ll" \) -type f -print0 | xargs -0 sed -i '' -E 's/BB#" << ([a-zA-Z0-9_]+)\.getNumber\(\)/" << printMBBReference(\1)/g'
* find . \( -name "*.txt" -o -name "*.s" -o -name "*.mir" -o -name "*.cpp" -o -name "*.h" -o -name "*.ll" \) -type f -print0 | xargs -0 sed -i '' -E 's/BB#([0-9]+)/%bb.\1/g'
* grep -nr 'BB#' and fix

Differential Revision: https://reviews.llvm.org/D40422

llvm-svn: 319665
2017-12-04 17:18:51 +00:00
Martin Storsjo eca862de07 [AArch64] Allow using emulated tls on platforms other than ELF
This matches how it is done on X86.

This allows using emulated tls on windows; in MinGW environments,
native tls isn't supported at the moment.

Set the right Data*bitsDirective for windows to match the existing
tests for other platforms. Make parts of the existing tests a regex,
to allow matching .section .rdata for windows, to avoid having to
duplicate the rest of the tests for windows.

Differential Revision: https://reviews.llvm.org/D40770

llvm-svn: 319644
2017-12-04 09:09:04 +00:00
Nirav Dave 839ff79a8d [DAG][AArch64] Disable post-legalization store
Disable post-legalization store for AArch64 backend which is causing
errors out-of-tree.

llvm-svn: 319607
2017-12-02 04:01:26 +00:00
Adam Nemet 9303f62255 [opt-remarks] If hotness threshold is set, ignore remarks without hotness
These are blocks that haven't not been executed during training.  For large
projects this could make a significant difference.  For the project, I was
looking at, I got an order of magnitude decrease in the size of the total YAML
files with this and r319235.

Differential Revision: https://reviews.llvm.org/D40678

Re-commit after fixing the failing testcase in rL319576, rL319577 and
rL319578.

llvm-svn: 319581
2017-12-01 20:41:38 +00:00
Adam Nemet 57783730fd Revert "[opt-remarks] If hotness threshold is set, ignore remarks without hotness"
This reverts commit r319556.

Something is not working with this when used with sample-based profiling.
Investigating...

llvm-svn: 319562
2017-12-01 18:12:29 +00:00
Adam Nemet 8d1fc2b65b [opt-remarks] If hotness threshold is set, ignore remarks without hotness
These are blocks that haven't not been executed during training.  For large
projects this could make a significant difference.  For the project, I was
looking at, I got an order of magnitude decrease in the size of the total YAML
files with this and r319235.

Differential Revision: https://reviews.llvm.org/D40678

llvm-svn: 319556
2017-12-01 17:02:04 +00:00
Volkan Keles a32ff00b00 GlobalISel: Enable the legalization of G_MERGE_VALUES and G_UNMERGE_VALUES
Summary: LegalizerInfo assumes all G_MERGE_VALUES and G_UNMERGE_VALUES instructions are legal, so it is not possible to legalize vector operations on illegal vector types. This patch fixes the problem by removing the related check and adding default actions for G_MERGE_VALUES and G_UNMERGE_VALUES.

Reviewers: qcolombet, ab, dsanders, aditya_nandakumar, t.p.northover, kristof.beyls

Reviewed By: dsanders

Subscribers: rovka, javed.absar, igorb, llvm-commits

Differential Revision: https://reviews.llvm.org/D39823

llvm-svn: 319524
2017-12-01 08:19:10 +00:00
Daniel Sanders aef1dfc690 [aarch64][globalisel] Legalize G_ATOMIC_CMPXCHG_WITH_SUCCESS and G_ATOMICRMW_*
G_ATOMICRMW_* is generally legal on AArch64. The exception is G_ATOMICRMW_NAND.

G_ATOMIC_CMPXCHG_WITH_SUCCESS needs to be lowered to G_ATOMIC_CMPXCHG with an
external comparison.

Note that IRTranslator doesn't generate these instructions yet.

llvm-svn: 319466
2017-11-30 20:11:42 +00:00
Amara Emerson d78d65c2a4 [GlobalISel][IRTranslator] Fix crash during translation of zero sized loads/stores/args/returns.
This fixes PR35358.

rdar://35619533

Differential Revision: https://reviews.llvm.org/D40604

llvm-svn: 319465
2017-11-30 20:06:02 +00:00
Francis Visoiu Mistrih c71cced0aa [CodeGen] Always use `printReg` to print registers in both MIR and debug
output

As part of the unification of the debug format and the MIR format,
always use `printReg` to print all kinds of registers.

Updated the tests using '_' instead of '%noreg' until we decide which
one we want to be the default one.

Differential Revision: https://reviews.llvm.org/D40421

llvm-svn: 319445
2017-11-30 16:12:24 +00:00
Francis Visoiu Mistrih 93ef145862 [CodeGen] Print "%vreg0" as "%0" in both MIR and debug output
As part of the unification of the debug format and the MIR format, avoid
printing "vreg" for virtual registers (which is one of the current MIR
possibilities).

Basically:

* find . \( -name "*.mir" -o -name "*.cpp" -o -name "*.h" -o -name "*.ll" \) -type f -print0 | xargs -0 sed -i '' -E "s/%vreg([0-9]+)/%\1/g"
* grep -nr '%vreg' . and fix if needed
* find . \( -name "*.mir" -o -name "*.cpp" -o -name "*.h" -o -name "*.ll" \) -type f -print0 | xargs -0 sed -i '' -E "s/ vreg([0-9]+)/ %\1/g"
* grep -nr 'vreg[0-9]\+' . and fix if needed

Differential Revision: https://reviews.llvm.org/D40420

llvm-svn: 319427
2017-11-30 12:12:19 +00:00
Daniel Sanders 766646517f [globalisel][tablegen] Add support for importing G_ATOMIC_CMPXCHG, G_ATOMICRMW_* rules from SelectionDAG.
GIM_CheckNonAtomic has been replaced by GIM_CheckAtomicOrdering to allow it to support a wider
range of orderings. This has then been used to import patterns using nodes such
as atomic_cmp_swap, atomic_swap, and atomic_load_*.

llvm-svn: 319232
2017-11-28 22:07:05 +00:00
Daniel Sanders 7b361b50d8 [aarch64][globalisel] Add missing tests from r319216
llvm-svn: 319220
2017-11-28 20:27:59 +00:00
Francis Visoiu Mistrih 9d7bb0cb40 [CodeGen] Print register names in lowercase in both MIR and debug output
As part of the unification of the debug format and the MIR format,
always print registers as lowercase.

* Only debug printing is affected. It now follows MIR.

Differential Revision: https://reviews.llvm.org/D40417

llvm-svn: 319187
2017-11-28 17:15:09 +00:00
Nirav Dave db77e57ea8 [DAG] Do MergeConsecutiveStores again before Instruction Selection
Summary:

Now that store-merge is only generates type-safe stores, do a second
pass just before instruction selection to allow lowered intrinsics to
be merged as well.

Reviewers: jyknight, hfinkel, RKSimon, efriedma, rnk, jmolloy

Subscribers: javed.absar, llvm-commits

Differential Revision: https://reviews.llvm.org/D33675

llvm-svn: 319036
2017-11-27 15:28:15 +00:00
Chad Rosier fe97d73674 [AArch64] Mark mrs of TPIDR_EL0 (thread pointer) as *having* side effects.
This partially reverts r298851.  The the underlying issue is that we don't
currently model the dependency between mrs (read system register) and
msr (write system register) instructions.

Something like the below should never be reordered:

 msr TPIDR_EL0, x0  ;; set thread pointer
 mrs x8, TPIDR_EL0  ;; read thread pointer

but was being reordered after r298851.  The functional part of the patch
that wasn't reverted needed to remain in place in order to not break
r299462.

PR35317

llvm-svn: 318788
2017-11-21 18:08:34 +00:00
Sander de Smalen 0c5a29b6be [AArch64][TableGen] Skip tied result operands for InstAlias
Summary:
This patch fixes an issue so that the right alias is printed when the instruction has tied operands. It checks the number of operands in the resulting instruction as opposed to the alias, and then skips over tied operands that should not be printed in the alias.

This allows to generate the preferred assembly syntax for the AArch64 'ins' instruction, which should always be displayed as 'mov' according to the ARM Architecture Reference Manual. Several unit tests have changed as a result, but only to reflect the preferred disassembly. Some other InstAlias patterns (movk/bic/orr) needed a slight adjustment to stop them becoming the default and breaking other unit tests.

Please note that the patch is mostly the same as https://reviews.llvm.org/D29219 which was reverted because of an issue found when running TableGen with the Address Sanitizer. That issue has been addressed in this iteration of the patch.


Reviewers: rengolin, stoklund, huntergr, SjoerdMeijer, rovka

Reviewed By: rengolin, SjoerdMeijer

Subscribers: fhahn, aemerson, javed.absar, kristof.beyls, llvm-commits

Differential Revision: https://reviews.llvm.org/D40030

llvm-svn: 318650
2017-11-20 14:36:40 +00:00
Quentin Colombet c0d34d38cb [AArch64] Map G_LOAD on FPR when the definition goes to a copy to FPR
We used to detect loads feeding fp instructions, but we were
failing to take into account cases where this happens through copies.
For instance, loads can fed copies coming from the ABI lowering
of floating point arguments/results.

llvm-svn: 318589
2017-11-18 04:28:59 +00:00
Quentin Colombet 63816c0957 [AArch64] Map G_STORE on FPR when the source comes from a FPR copy
We used to detect that stores were fed by fp instructions, but we were
failing to take into account cases where this happens through copies.
For instance, stores can be fed by copies coming from the ABI lowering
of floating point arguments.

llvm-svn: 318588
2017-11-18 04:28:58 +00:00
Quentin Colombet fe538f7145 [RegisterBankInfo] Relax the assert of having matching type sizes on default mappings
Instead of asserting that the type sizes are exactly equal, we check
that the new size is big enough to contain the original type.
We have to relax this constrain because, right now, we sometimes
specify that things that are smaller than a storage type are legal
instead of widening everything to the size of a storage type.
E.g., we say that G_AND s16 is legal and we map that on GPR32.

This is something we may revisit in the future (either by changing
the legalization process or keeping track separately of the storage
size and the size of the type), but let us reflect the reality of
the situation for now.

llvm-svn: 318587
2017-11-18 04:28:58 +00:00
Quentin Colombet 91801f68aa [AArch64][RegisterBankInfo] Teach instruction mapping about gpr32 -> fpr16 cross copies
Turns out this copies can actually occur because of the way we lower the
ABI for half.

llvm-svn: 318586
2017-11-18 04:28:56 +00:00
Aditya Nandakumar 69855491ee [GISel]: DCE copy instructions during legalization
We might have instructions such as ext(copy(trunc)), and while cleaning
up legalization artifacts, we can also dce the copies that are in
between legalization artifacts.

llvm-svn: 318501
2017-11-17 02:44:55 +00:00
Aditya Nandakumar e6201c8724 [GISel]: Rework legalization algorithm for better elimination of
artifacts along with DCE

Legalization Artifacts are all those insts that are there to make the
type system happy. Currently, the target needs to say all combinations
of extends and truncs are legal and there's no way of verifying that
post legalization, we only have *truly* legal instructions. This patch
changes roughly the legalization algorithm to process all illegal insts
at one go, and then process all truncs/extends that were added to
satisfy the type constraints separately trying to combine trivial cases
until they converge. This has the added benefit that, the target
legalizerinfo can only say which truncs and extends are okay and the
artifact combiner would combine away other exts and truncs.

Updated legalization algorithm to roughly the following pseudo code.

WorkList Insts, Artifacts;
collect_all_insts_and_artifacts(Insts, Artifacts);

do {
  for (Inst in Insts)
         legalizeInstrStep(Inst, Insts, Artifacts);
  for (Artifact in Artifacts)
         tryCombineArtifact(Artifact, Insts, Artifacts);
} while(!Insts.empty());

Also, wrote a simple wrapper equivalent to SetVector, except for
erasing, it avoids moving all elements over by one and instead just
nulls them out.

llvm-svn: 318210
2017-11-14 22:42:19 +00:00
Daniel Sanders b78ac6e322 [globalisel][tablegen] Add support for extload.
llvm-svn: 318068
2017-11-13 18:30:23 +00:00
Matt Arsenault 90e4f719e1 Fix some misc. -enable-var-scope violations
llvm-svn: 318006
2017-11-13 01:47:52 +00:00
Daniel Sanders 7e52367398 [globalisel][tablegen] Import signextload and zeroextload.
Allow a pattern rewriter to be installed in CodeGenDAGPatterns and use it to
correct situations where SelectionDAG and GlobalISel disagree on
representation. For example, it would rewrite:
  (sextload:i32 $ptr)<<unindexedload>><<sextload>><<sextloadi16>
to:
  (sext:i32 (load:i16 $ptr)<<unindexedload>>)

I'd have preferred to replace the fragments and have the expansion happen
naturally as part of PatFrag expansion but the type inferencing system can't
cope with loads of types narrower than those mentioned in register classes.
This is because the SDTCisInt's on the sext constrain both the result and
operand to the 'legal' integer types (where legal is defined as 'a register
class can contain the type') which immediately rules the narrower types out.
Several targets (those with only one legal integer type) would then go on to
crash on the SDTCisOpSmallerThanOp<> when it removes all the possible types
for the result of the extend.

Also, improve isObviouslySafeToFold() slightly to automatically return true for
neighbouring instructions. There can't be any re-ordering problems if
re-ordering isn't happenning. We'll need to improve it further to handle
sign/zero-extending loads when the extend and load aren't immediate neighbours
though.

llvm-svn: 317971
2017-11-11 03:23:44 +00:00
Kristof Beyls af9814a1fc [GlobalISel] Enable legalizing non-power-of-2 sized types.
This changes the interface of how targets describe how to legalize, see
the below description.

1. Interface for targets to describe how to legalize.

In GlobalISel, the API in the LegalizerInfo class is the main interface
for targets to specify which types are legal for which operations, and
what to do to turn illegal type/operation combinations into legal ones.

For each operation the type sizes that can be legalized without having
to change the size of the type are specified with a call to setAction.
This isn't different to how GlobalISel worked before. For example, for a
target that supports 32 and 64 bit adds natively:

  for (auto Ty : {s32, s64})
    setAction({G_ADD, 0, s32}, Legal);

or for a target that needs a library call for a 32 bit division:

  setAction({G_SDIV, s32}, Libcall);

The main conceptual change to the LegalizerInfo API, is in specifying
how to legalize the type sizes for which a change of size is needed. For
example, in the above example, how to specify how all types from i1 to
i8388607 (apart from s32 and s64 which are legal) need to be legalized
and expressed in terms of operations on the available legal sizes
(again, i32 and i64 in this case). Before, the implementation only
allowed specifying power-of-2-sized types (e.g. setAction({G_ADD, 0,
s128}, NarrowScalar).  A worse limitation was that if you'd wanted to
specify how to legalize all the sized types as allowed by the LLVM-IR
LangRef, i1 to i8388607, you'd have to call setAction 8388607-3 times
and probably would need a lot of memory to store all of these
specifications.

Instead, the legalization actions that need to change the size of the
type are specified now using a "SizeChangeStrategy".  For example:

   setLegalizeScalarToDifferentSizeStrategy(
       G_ADD, 0, widenToLargerAndNarrowToLargest);

This example indicates that for type sizes for which there is a larger
size that can be legalized towards, do it by Widening the size.
For example, G_ADD on s17 will be legalized by first doing WidenScalar
to make it s32, after which it's legal.
The "NarrowToLargest" indicates what to do if there is no larger size
that can be legalized towards. E.g. G_ADD on s92 will be legalized by
doing NarrowScalar to s64.

Another example, taken from the ARM backend is:
   for (unsigned Op : {G_SDIV, G_UDIV}) {
     setLegalizeScalarToDifferentSizeStrategy(Op, 0,
         widenToLargerTypesUnsupportedOtherwise);
     if (ST.hasDivideInARMMode())
       setAction({Op, s32}, Legal);
     else
       setAction({Op, s32}, Libcall);
   }

For this example, G_SDIV on s8, on a target without a divide
instruction, would be legalized by first doing action (WidenScalar,
s32), followed by (Libcall, s32).

The same principle is also followed for when the number of vector lanes
on vector data types need to be changed, e.g.:

   setAction({G_ADD, LLT::vector(8, 8)}, LegalizerInfo::Legal);
   setAction({G_ADD, LLT::vector(16, 8)}, LegalizerInfo::Legal);
   setAction({G_ADD, LLT::vector(4, 16)}, LegalizerInfo::Legal);
   setAction({G_ADD, LLT::vector(8, 16)}, LegalizerInfo::Legal);
   setAction({G_ADD, LLT::vector(2, 32)}, LegalizerInfo::Legal);
   setAction({G_ADD, LLT::vector(4, 32)}, LegalizerInfo::Legal);
   setLegalizeVectorElementToDifferentSizeStrategy(
       G_ADD, 0, widenToLargerTypesUnsupportedOtherwise);

As currently implemented here, vector types are legalized by first
making the vector element size legal, followed by then making the number
of lanes legal. The strategy to follow in the first step is set by a
call to setLegalizeVectorElementToDifferentSizeStrategy, see example
above.  The strategy followed in the second step
"moreToWiderTypesAndLessToWidest" (see code for its definition),
indicating that vectors are widened to more elements so they map to
natively supported vector widths, or when there isn't a legal wider
vector, split the vector to map it to the widest vector supported.

Therefore, for the above specification, some example legalizations are:
  * getAction({G_ADD, LLT::vector(3, 3)})
    returns {WidenScalar, LLT::vector(3, 8)}
  * getAction({G_ADD, LLT::vector(3, 8)})
    then returns {MoreElements, LLT::vector(8, 8)}
  * getAction({G_ADD, LLT::vector(20, 8)})
    returns {FewerElements, LLT::vector(16, 8)}


2. Key implementation aspects.

How to legalize a specific (operation, type index, size) tuple is
represented by mapping intervals of integers representing a range of
size types to an action to take, e.g.:

       setScalarAction({G_ADD, LLT:scalar(1)},
                       {{1, WidenScalar},  // bit sizes [ 1, 31[
                        {32, Legal},       // bit sizes [32, 33[
                        {33, WidenScalar}, // bit sizes [33, 64[
                        {64, Legal},       // bit sizes [64, 65[
                        {65, NarrowScalar} // bit sizes [65, +inf[
                       });

Please note that most of the code to do the actual lowering of
non-power-of-2 sized types is currently missing, this is just trying to
make it possible for targets to specify what is legal, and how non-legal
types should be legalized.  Probably quite a bit of further work is
needed in the actual legalizing and the other passes in GlobalISel to
support non-power-of-2 sized types.

I hope the documentation in LegalizerInfo.h and the examples provided in the
various {Target}LegalizerInfo.cpp and LegalizerInfoTest.cpp explains well
enough how this is meant to be used.

This drops the need for LLT::{half,double}...Size().


Differential Revision: https://reviews.llvm.org/D30529

llvm-svn: 317560
2017-11-07 10:34:34 +00:00
Bjorn Pettersson a42ed3e361 [MIRPrinter] Use %subreg.xxx syntax for subregister index operands
Summary:
Print %subreg.<subregidxname> instead of just the subregister
index when printing immediate operands corresponding to subreg
indices in INSERT_SUBREG, EXTRACT_SUBREG, SUBREG_TO_REG and
REG_SEQUENCE.

Reviewers: qcolombet, MatzeB

Reviewed By: MatzeB

Subscribers: nhaehnle, javed.absar, llvm-commits

Differential Revision: https://reviews.llvm.org/D39696

llvm-svn: 317513
2017-11-06 21:46:06 +00:00
Evandro Menezes 9dcf099944 [AArch64] Fix the number of iterations for the Newton series
The number of iterations was incorrectly determined for DP FP vector types
and the tests were insufficient to flag this issue.

Differential revision: https://reviews.llvm.org/D39507

llvm-svn: 317349
2017-11-03 18:56:36 +00:00
Martin Storsjo 9befcd7d8d [AArch64] Use dwarf exception handling on MinGW
Ideally we should probably produce WinEH here as well, but until
then, we can use dwarf exceptions, without any further changes
required in clang, libunwind or libcxxabi.

Differential Revision: https://reviews.llvm.org/D39535

llvm-svn: 317304
2017-11-03 07:33:20 +00:00
Quentin Colombet b6afac1f9a [AArch64][RegisterBankInfo] Add mapping for G_FPEXT.
This fixes http://llvm.org/PR32560. We were missing a description for
half floating point type and as a result were using the FPR 32 mapping.
Because of the size mismatch the generic code was complaining that the
default mapping is not appropriate. Fix the mapping description so that
the default mapping can be properly applied.

llvm-svn: 317287
2017-11-02 23:38:19 +00:00
Francis Visoiu Mistrih 66d2c269dc [AsmPrinterDwarf] Add support for .cfi_restore directive
As of today we only use .cfi_offset to specify the offset of a CSR, but
we never use .cfi_restore when the CSR is restored.

If we want to perform a more advanced type of shrink-wrapping, we need
to use .cfi_restore in order to switch the CFI state between blocks.

This patch only aims at adding support for the directive.

Differential Revision: https://reviews.llvm.org/D36114

llvm-svn: 317199
2017-11-02 12:00:58 +00:00
Daniel Sanders 9cbe7c7f93 [globalisel][tablegen] Add support for multi-insn emission
The importer will now accept nested instructions in the result pattern such as
(ADDWrr $a, (SUBWrr $b, $c)). This is only valid when the nested instruction
def's a single vreg and the parent instruction consumes a single vreg where a
nested instruction is specified. The importer will automatically create a vreg
to connect the two using the type information from the pattern. This vreg will
be constrained to the register classes given in the instruction definitions*.

* REG_SEQUENCE is explicitly rejected because of this. The definition doesn't
  constrain to a register class and it therefore needs special handling.

llvm-svn: 317117
2017-11-01 19:57:57 +00:00
Sanjay Patel b049173157 [SimplifyCFG] use pass options and remove the latesimplifycfg pass
This is no-functional-change-intended.

This is repackaging the functionality of D30333 (defer switch-to-lookup-tables) and 
D35411 (defer folding unconditional branches) with pass parameters rather than a named
"latesimplifycfg" pass. Now that we have individual options to control the functionality,
we could decouple when these fire (but that's an independent patch if desired). 

The next planned step would be to add another option bit to disable the sinking transform
mentioned in D38566. This should also make it clear that the new pass manager needs to
be updated to limit simplifycfg in the same way as the old pass manager.

Differential Revision: https://reviews.llvm.org/D38631

llvm-svn: 316835
2017-10-28 18:43:07 +00:00
Martin Storsjo 373c8efa1e [AArch64] Add support for dllimport of values and functions
Previously, the dllimport attribute did the right thing in terms
of treating it as a pointer to a value, but this makes sure the
names get mangled properly, and calls to such functions load the
function from the __imp_ pointer.

This is based on SVN r212431 and r212430 where the same was
implemented for ARM.

Differential Revision: https://reviews.llvm.org/D38530

llvm-svn: 316555
2017-10-25 07:25:18 +00:00
Justin Bogner 6c452834a1 MIR: Print the register class or bank in vreg defs
This updates the MIRPrinter to include the regclass when printing
virtual register defs, which is already valid syntax for the
parser. That is, given 64 bit %0 and %1 in a "gpr" regbank,

  %1(s64) = COPY %0(s64)

would now be written as

  %1:gpr(s64) = COPY %0(s64)

While this change alone introduces a bit of redundancy with the
registers block, it allows us to update the tests to be more concise
and understandable and brings us closer to being able to remove the
registers block completely.

Note: We generally only print the class in defs, but there is one
exception. If there are uses without any defs whatsoever, we'll print
the class on all uses. I'm not completely convinced this comes up in
meaningful machine IR, but for now the MIRParser and MachineVerifier
both accept that kind of stuff, so we don't want to have a situation
where we can print something we can't parse.

llvm-svn: 316479
2017-10-24 18:04:54 +00:00
Omer Paparo Bivas 2251c79aba [MC] Adding code padding for performance stability - infrastructure. NFC.
Infrastructure designed for padding code with nop instructions in key places such that preformance improvement will be achieved.
The infrastructure is implemented such that the padding is done in the Assembler after the layout is done and all IPs and alignments are known.
This patch by itself in a NFC. Future patches will make use of this infrastructure to implement required policies for code padding.

Reviewers:
aaboud
zvi
craig.topper
gadi.haber

Differential revision: https://reviews.llvm.org/D34393

Change-Id: I92110d0c0a757080a8405636914a93ef6f8ad00e
llvm-svn: 316413
2017-10-24 06:16:03 +00:00
Jessica Paquette 9df7fde269 [MachineOutliner] Add optimisation remarks for successful outlining
This commit adds optimisation remarks for outlining which fire when a function
is successfully outlined.

To do this, OutlinedFunctions must now contain references to their Candidates.
Since the Candidates must still be sorted and worked on separately, this is
done by working on everything in terms of shared_ptrs to Candidates. This is
good; it means that we can easily move everything to outlining in terms of
the OutlinedFunctions rather than the individual Candidates. This is far more
intuitive than what's currently there!

(Remarks are output when a function is created for some group of Candidates.
In a later commit, all of the outlining logic should be rewritten so that we
loop over OutlinedFunctions rather than over Candidates.)
 

llvm-svn: 316396
2017-10-23 23:36:46 +00:00
Aditya Nandakumar 4dfd2590dc [GISel][AArch64]: Fix illegal Generic copies in tests
This is in preparation for a verifier check that makes sure copies are
of the same size (when generic virtual registers are involved).

llvm-svn: 316387
2017-10-23 22:53:04 +00:00
George Burgess IV 8a0e4bc972 Don't crash when we see unallocatable registers in clobbers
This fixes a bug where we'd crash given code like the test-case from
https://bugs.llvm.org/show_bug.cgi?id=30792 . Instead, we let the
offending clobber silently slide through.

This doesn't fully fix said bug, since the assembler will still complain
the moment it sees a crypto/fp/vector op, and we still don't diagnose
calls that require vector regs.

Differential Revision: https://reviews.llvm.org/D39030

llvm-svn: 316374
2017-10-23 20:46:36 +00:00
Daniel Sanders d66e0901ae [globalisel][tablegen] Import stores and allow GISel to automatically substitute zero regs like WZR/XZR/$zero.
This patch enables the import of stores. Unfortunately, doing so by itself,
loses an optimization where storing 0 to memory makes use of WZR/XZR.

To mitigate this, this patch also introduces a new feature that allows register
operands to nominate a zero register. When this is done, GlobalISel will
substitute (G_CONSTANT 0) with the nominated register automatically. This
is currently configured to only apply to the stores.

Applying it to GPR32/GPR64 register classes in general will be done after
review see (https://reviews.llvm.org/D39150).

llvm-svn: 316360
2017-10-23 18:19:24 +00:00
Justin Bogner 876ad287d1 GISel: Canonicalize select tests using update_mir_test_checks
This runs `udpate_mir_test_checks --add-vreg-checks` on the tests taht
are already more or less in the format that generates, so that there
will be less churn in some upcoming changes.

llvm-svn: 316139
2017-10-18 23:33:31 +00:00
Justin Bogner f8dc015bd1 AArch64/GISel: Modernize the localizer test
llvm-svn: 316138
2017-10-18 23:26:24 +00:00
Justin Bogner d45849f703 Canonicalize a large number of mir tests using update_mir_test_checks
This converts a large and somewhat arbitrary set of tests to use
update_mir_test_checks. I ran the script on all of the tests I expect
to need to modify for an upcoming mir syntax change and kept the ones
that obviously didn't change the tests in ways that might make it
harder to understand.

llvm-svn: 316137
2017-10-18 23:18:12 +00:00