Commit Graph

9452 Commits

Author SHA1 Message Date
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 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
Pablo Barrio 2b4385846c Fix function pointer tail calls in armv8-M.base
Summary:
The compiler fails with the following error message:

fatal error: error in backend: ran out of registers during
register allocation

Tail call optimization for Armv8-M.base fails to meet all the required
constraints when handling calls to function pointers where the
arguments take up r0-r3. This is because the pointer to the
function to be called can only be stored in r0-r3, but these are
all occupied by arguments. This patch makes sure that tail call
optimization does not try to handle this type of calls.

Reviewers: chill, MatzeB, olista01, rengolin, efriedma

Reviewed By: olista01, efriedma

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

Differential Revision: https://reviews.llvm.org/D40706

llvm-svn: 319664
2017-12-04 16:55:49 +00:00
Oliver Stannard 7ab60605f8 Revert r319649 - [Asm, ARM] Add fallback diag for multiple invalid operands
This is causing a failure in the llvm-clang-x86_64-expensive-checks-win
buildbot, and I can't reproduce it locally, so reverting until I can work out
what is wrong.

llvm-svn: 319654
2017-12-04 13:42:22 +00:00
Oliver Stannard 7cd4db94f8 [Asm, ARM] Add fallback diag for multiple invalid operands
This adds a "invalid operands for instruction" diagnostic for
instructions where there is an instruction encoding with the correct
mnemonic and which is available for this target, but where multiple
operands do not match those which were provided. This makes it clear
that there is some combination of operands that is valid for the current
target, which the default diagnostic of "invalid instruction" does not.

Since this is a very general error, we only emit it if we don't have a
more specific error.

Differential revision: https://reviews.llvm.org/D36747

llvm-svn: 319649
2017-12-04 12:02:32 +00:00
Martin Storsjo c85cc41801 [ARM] 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.

Differential Revision: https://reviews.llvm.org/D40769

llvm-svn: 319643
2017-12-04 09:08:55 +00:00
Nirav Dave 3e76e1e89e [DAG][ARM] Revert "Reenable post-legalize store merge"
due to failures in AArch and ARM code gen.

llvm-svn: 319587
2017-12-01 21:55:47 +00:00
Nirav Dave eb2b24fded [ARM][DAG] Reenable post-legalize store merge
Summary: Reenable post-legalize stores with constant merging computation and cofrresponding test case.

Reviewers: eastig, efriedma

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

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

llvm-svn: 319547
2017-12-01 14:49:26 +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
Diana Picus f003d9ff95 [ARM GlobalISel] Bail out for byval
Fallback if we have a byval parameter or argument since we don't support
them yet.

llvm-svn: 319428
2017-11-30 12:23:44 +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
Nirav Dave bafaa53c4d [ARM][DAG] Revert Disable post-legalization store merge for ARM
Partially reverting enabling of post-legalization store merge
(r319036) for just ARM backend as it is causing incorrect code
in some Thumb2 cases.

llvm-svn: 319331
2017-11-29 18:06:13 +00:00
Diana Picus 863b5b05f1 [ARM GlobalISel] Fix selecting G_BRCOND
When lowering a G_BRCOND, we generate a TSTri of the condition against
1, which sets the flags, and then a Bcc which branches based on the
value of the flags.

Unfortunately, we were using the wrong condition code to check whether
we need to branch (EQ instead of NE), which caused all our branches to
do the opposite of what they were intended to do. This patch fixes the
issue by using the correct condition code.

llvm-svn: 319313
2017-11-29 14:20:06 +00:00
Oliver Stannard 9ea2eaeb50 [ARM] Add support for armv7e-m to the .arch directive
This will allow compilation of assembly files targeting armv7e-m without having
to specify the Tag_CPU_arch attribute as a workaround.

Differential revision: https://reviews.llvm.org/D40370

Patch by Ian Tessier!

llvm-svn: 319303
2017-11-29 10:12:15 +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
Francis Visoiu Mistrih 9d419d3b0c [CodeGen] Rename functions PrintReg* to printReg*
LLVM Coding Standards:
  Function names should be verb phrases (as they represent actions), and
  command-like function should be imperative. The name should be camel
  case, and start with a lower case letter (e.g. openFile() or isFoo()).

Differential Revision: https://reviews.llvm.org/D40416

llvm-svn: 319168
2017-11-28 12:42:37 +00:00
Matthias Braun 5d01e708e1 ARM: Fix PR32578
https://llvm.org/PR32578

I simplified and converted the reproducer into a lit test.

Patch by Vedant Kumar!

llvm-svn: 319130
2017-11-28 01:17:52 +00:00
Momchil Velikov bd2c7eb923 [ARM] Fix an off-by-one error when restoring LR for 16-bit Thumb
The commit https://reviews.llvm.org/rL318143 computes incorrectly to offset to
restore LR from.

The number of tPOP operands is 2 (condition) + 2 (implicit def and use of SP) +
count of the popped registers. We need to load LR from just past the last
register, hence the correct offset should be either getNumOperands() - 4 and
getNumExplicitOperands() - 2 (multiplied by 4).

Differential revision: https://reviews.llvm.org/D40305

llvm-svn: 319014
2017-11-27 10:13:14 +00:00
Diana Picus c01f7f131b [ARM GlobalISel] Support G_FDIV for s32 and s64
TableGen already generates code for selecting a G_FDIV, so we only need
to add a test.

For the legalizer and reg bank select, we do the same thing as for the
other floating point binary operations: either mark as legal if we have
a FP unit or lower to a libcall, and map to the floating point
registers.

llvm-svn: 318915
2017-11-23 13:26:07 +00:00
Diana Picus 9faa09b21e [ARM GlobalISel] Support G_FMUL for s32 and s64
TableGen already generates code for selecting a G_FMUL, so we only need
to add a test for that part.

For the legalizer and reg bank select, we do the same thing as the other
floating point binary operators: either mark as legal if we have a FP
unit or lower to a libcall, and map to the floating point registers.

llvm-svn: 318910
2017-11-23 12:44:20 +00:00
Oliver Stannard 9cb89f6611 [ARM] Remove pre-UAL FLDM/FSTM aliases
These are pre-UAL syntax, and we don't support any other pre-UAL instructions,
with the exception of FLDMX/FSTMX, which don't have a UAL equivalent. Therefore
there's no reason to keep them or their AsmParser hacks around.

With the AsmParser hacks removed, the FLDMX and FSTMX instructions get the same
operand diagnostics as the UAL instructions.

Differential revision: https://reviews.llvm.org/D39196

llvm-svn: 318777
2017-11-21 16:20:25 +00:00
Oliver Stannard 1e6d4b9e62 [ARM] Don't omit non-default predication code
This was causing the (invalid) predicated versions of the NEON VRINTX and
VRINTZ instructions to be accepted, with the condition code being ignored.

Also, there is no NEON VRINTR instruction, so that part of the check was not
necessary.

Differential revision: https://reviews.llvm.org/D39193

llvm-svn: 318771
2017-11-21 15:34:15 +00:00
Oliver Stannard 1e73e95f3c [Asm] Improve "too few operands" errors
- We can still emit this error if the actual instruction has two or more
  operands missing compared to the expected one.
- We should only emit this error once per instruction.

Differential revision: https://reviews.llvm.org/D36746

llvm-svn: 318770
2017-11-21 15:16:50 +00:00
Oliver Stannard d6ca9879ba [ARM] Add diagnostics for SPR/DPR lists
Differential revision: https://reviews.llvm.org/D39195

llvm-svn: 318766
2017-11-21 15:06:01 +00:00
Martell Malone 51d82696db [ARM] Use SEH exceptions on thumbv7-windows
Reviewers: mstorsjo

Differential Revision: https://reviews.llvm.org/D40286

llvm-svn: 318756
2017-11-21 11:30:20 +00:00
Eugene Leviant 6bc35a93e6 [MI scheduler] Fix VADD and VSUB in cortex-a57 model
This patch fixes instregex for interger vector add/sub instructions

Differential revision: https://reviews.llvm.org/D40254

llvm-svn: 318749
2017-11-21 11:01:28 +00:00
Martin Storsjo b4c907edd7 [ARM] Use dwarf exception handling on MinGW
Enabling and using dwarf exceptions seems like an easier path
to take, than to make the COFF/ARM backend output EHABI directives.
Previously, no EH model was enabled at all on this target.

There's no point in setting UseIntegratedAssembler to false since
GNU binutils doesn't support Windows on ARM, and since we don't
need to support external assembler, we don't need to use register
numbers in cfi directives.

Differential Revision: https://reviews.llvm.org/D39532

llvm-svn: 318510
2017-11-17 08:04:40 +00:00
David Blaikie b3bde2ea50 Fix a bunch more layering of CodeGen headers that are in Target
All these headers already depend on CodeGen headers so moving them into
CodeGen fixes the layering (since CodeGen depends on Target, not the
other way around).

llvm-svn: 318490
2017-11-17 01:07:10 +00:00
Yi Kong 39bcd4ed3e [ARM] 't' asm constraint should accept i32
't' constraint normally only accepts f32 operands, but for VCVT the
operands can be i32. LLVM is overly restrictive and rejects asm like:

  float foo() {
    float result;
    __asm__ __volatile__(
      "vcvt.f32.s32 %[result], %[arg1]\n"
      : [result]"=t"(result)
      : [arg1]"t"(0x01020304) );
    return result;
  }

Relax the value type for 't' constraint to either f32 or i32.

Differential Revision: https://reviews.llvm.org/D40137

llvm-svn: 318472
2017-11-16 23:38:17 +00:00
Daniel Sanders f76f315436 [globalisel][tablegen] Generate rule coverage and use it to identify untested rules
Summary:
This patch adds a LLVM_ENABLE_GISEL_COV which, like LLVM_ENABLE_DAGISEL_COV,
causes TableGen to instrument the generated table to collect rule coverage
information. However, LLVM_ENABLE_GISEL_COV goes a bit further than
LLVM_ENABLE_DAGISEL_COV. The information is written to files
(${CMAKE_BINARY_DIR}/gisel-coverage-* by default). These files can then be
concatenated into ${LLVM_GISEL_COV_PREFIX}-all after which TableGen will
read this information and use it to emit warnings about untested rules.

This technique could also be used by SelectionDAG and can be further
extended to detect hot rules and give them priority over colder rules.

Usage:
* Enable LLVM_ENABLE_GISEL_COV in CMake
* Build the compiler and run some tests
* cat gisel-coverage-[0-9]* > gisel-coverage-all
* Delete lib/Target/*/*GenGlobalISel.inc*
* Build the compiler

Known issues:
* ${LLVM_GISEL_COV_PREFIX}-all must be generated as a manual
  step due to a lack of a portable 'cat' command. It should be the
  concatenation of all ${LLVM_GISEL_COV_PREFIX}-[0-9]* files.
* There's no mechanism to discard coverage information when the ruleset
  changes

Depends on D39742

Reviewers: ab, qcolombet, t.p.northover, aditya_nandakumar, rovka

Reviewed By: rovka

Subscribers: vsk, arsenm, nhaehnle, mgorny, kristof.beyls, javed.absar, igorb, llvm-commits

Differential Revision: https://reviews.llvm.org/D39747

llvm-svn: 318356
2017-11-16 00:46:35 +00:00
Daniel Sanders 725584e26d Add backend name to Target to enable runtime info to be fed back into TableGen
Summary:
Make it possible to feed runtime information back to tablegen to enable
profile-guided tablegen-eration, detection of untested tablegen definitions, etc.

Being a cross-compiler by nature, LLVM will potentially collect data for multiple
architectures (e.g. when running 'ninja check'). We therefore need a way for
TableGen to figure out what data applies to the backend it is generating at the
time. This patch achieves that by including the name of the 'def X : Target ...'
for the backend in the TargetRegistry.

Reviewers: qcolombet

Reviewed By: qcolombet

Subscribers: jholewinski, arsenm, jyknight, aditya_nandakumar, sdardis, nemanjai, ab, nhaehnle, t.p.northover, javed.absar, qcolombet, llvm-commits, fedor.sergeev

Differential Revision: https://reviews.llvm.org/D39742

llvm-svn: 318352
2017-11-15 23:55:44 +00:00
Momchil Velikov 4a91fb93db [ARM] Split Arm jump table branch into i12 and rs suffixed versions
This is a refactoring/cleanup of Arm `addrmode2` operand class. The patch
removes it completely.

Differential Revision: https://reviews.llvm.org/D39832

llvm-svn: 318291
2017-11-15 12:02:55 +00:00
Martin Storsjo 4629f52312 [ARM, AArch64] Fix an assert message, Darwin isn't the only target supporting TLS. NFC.
llvm-svn: 318184
2017-11-14 19:57:59 +00:00
Tim Northover 5cdc4f9c33 ARM: correctly update CFG when splitting BB to fix branch.
Because the block-splitting code is multi-purpose, we have to meddle with the
branches when using it to fixup a conditional branch destination. We got the
code right, but forgot to update the CFG so the verifier complained when
expensive checks were on.

Probably harmless since constant-islands comes so late, but best to fix it
anyway.

llvm-svn: 318148
2017-11-14 11:43:54 +00:00
Diana Picus 21a42bcc0b [ARM GlobalISel] Remove C++ code for G_CONSTANT
Get rid of the handwritten instruction selector code for handling
G_CONSTANT. This code wasn't checking all the preconditions correctly
anyway, so it's better to leave it to TableGen, which can handle at
least some cases correctly (e.g. MOVi, MOVi16, folding into binary
operations). Also add tests to cover those cases.

llvm-svn: 318146
2017-11-14 11:20:32 +00:00
Momchil Velikov dc86e1444d [ARM] Fix incorrect conversion of a tail call to an ordinary call
When we emit a tail call for Armv8-M, but then discover that the caller needs to
save/restore `LR`, we convert the tail call to an ordinary one, since restoring
`LR` takes extra instructions, which may negate the benefits of the tail
call. If the callee, however, takes stack arguments, this conversion is
incorrect, since nothing has been done to pass the stack arguments.

Thus the patch reverts https://reviews.llvm.org/rL294000

Also, we improve the instruction sequence for popping `LR` in the case when we
couldn't immediately find a scratch low register, but we can use as a temporary
one of the callee-saved low registers and restore `LR` before popping other
callee-saves.

Differential Revision: https://reviews.llvm.org/D39599

llvm-svn: 318143
2017-11-14 10:36:52 +00:00
Evgeniy Stepanov 76d5ac4906 [arm] Fix Unnecessary reloads from GOT.
Summary:
This fixes PR35221.
Use pseudo-instructions to let MachineCSE hoist global address computation.

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

Differential Revision: https://reviews.llvm.org/D39871

llvm-svn: 318081
2017-11-13 20:45:38 +00:00
Momchil Velikov 842aa90192 [ARM] Place jump table as the first operand in additions
When generating table jump code for switch statements, place the jump
table label as the first operand in the various addition instructions
in order to enable addressing mode selectors to better match index
computation and possibly fold them into the addressing mode of the
table entry load instruction.

Differential revision: https://reviews.llvm.org/D39752

llvm-svn: 318033
2017-11-13 11:56:48 +00:00
Mandeep Singh Grang d104673257 [llvm] Remove redundant return [NFC]
Reviewers: davidxl, olista01, Eugene.Zelenko

Reviewed By: Eugene.Zelenko

Subscribers: sdardis, javed.absar, llvm-commits

Differential Revision: https://reviews.llvm.org/D39917

llvm-svn: 317995
2017-11-12 03:47:50 +00:00
Jonas Paulsson 4b017e682d [RegAlloc, SystemZ] Increase number of LOCRs by passing "hard" regalloc hints.
* The method getRegAllocationHints() is now of bool type instead of void. If
true is returned, regalloc (AllocationOrder) will *only* try to allocate the
hints, as opposed to merely trying them before non-hinted registers.

* TargetRegisterInfo::getRegAllocationHints() is implemented for SystemZ with
an increase in number of LOCRs.

In this case, it is desired to force the hints even though there is a slight
increase in spilling, because if a non-hinted register would be allocated,
the LOCRMux pseudo would have to be expanded with a jump sequence. The LOCR
(Load On Condition) SystemZ instruction must have both operands in either the
low or high part of the 64 bit register.

Reviewers: Quentin Colombet and Ulrich Weigand
https://reviews.llvm.org/D36795

llvm-svn: 317879
2017-11-10 08:46:26 +00:00
David Blaikie 3f833edc7c Target/TargetInstrInfo.h -> CodeGen/TargetInstrInfo.h to match layering
This header includes CodeGen headers, and is not, itself, included by
any Target headers, so move it into CodeGen to match the layering of its
implementation.

llvm-svn: 317647
2017-11-08 01:01:31 +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
David Blaikie 1be62f0327 Move TargetFrameLowering.h to CodeGen where it's implemented
This header already includes a CodeGen header and is implemented in
lib/CodeGen, so move the header there to match.

This fixes a link error with modular codegeneration builds - where a
header and its implementation are circularly dependent and so need to be
in the same library, not split between two like this.

llvm-svn: 317379
2017-11-03 22:32:11 +00:00
Diana Picus acf4bf21ab [ARM GlobalISel] Move the check for Thumb higher up
We're currently bailing out for Thumb targets while lowering formal
parameters, but there used to be some other checks before it, which
could've caused some functions (e.g. those without formal parameters) to
sneak through unnoticed.

llvm-svn: 317312
2017-11-03 10:30:12 +00:00
Sam Parker 242052c6b4 [ARM] and, or, xor and add with shl combine
The generic dag combiner will fold:

(shl (add x, c1), c2) -> (add (shl x, c2), c1 << c2)
(shl (or x, c1), c2) -> (or (shl x, c2), c1 << c2)

This can create constants which are too large to use as an immediate.
Many ALU operations are also able of performing the shl, so we can
unfold the transformation to prevent a mov imm instruction from being
generated.

Other patterns, such as b + ((a << 1) | 510), can also be simplified
in the same manner.

Differential Revision: https://reviews.llvm.org/D38084

llvm-svn: 317197
2017-11-02 10:43:10 +00:00
Roger Ferrer Ibanez 9dfbc10522 Revert r313618 "[ARM] Use ADDCARRY / SUBCARRY"
That change causes PR35103, so reverting until I figure it out.

llvm-svn: 317092
2017-11-01 14:06:57 +00:00
Javed Absar 5cde1ccb29 [GlobalISel|ARM] : Allow legalizing G_FSUB
Adding support for VSUB.
Reviewed by: @rovka
Differential Revision: https://reviews.llvm.org/D39261

llvm-svn: 316902
2017-10-30 13:51:56 +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