Commit Graph

808 Commits

Author SHA1 Message Date
Mehdi Amini
dc4dccabf3 Remove getDataLayout() from TargetSelectionDAGInfo (had no users)
Summary:
Remove empty subclass in the process.

This change is part of a series of commits dedicated to have a single
DataLayout during compilation by using always the one owned by the
module.

Reviewers: echristo

Subscribers: jholewinski, llvm-commits, rafael, yaron.keren, ted

Differential Revision: http://reviews.llvm.org/D11045

From: Mehdi Amini <mehdi.amini@apple.com>

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@241780 91177308-0d34-0410-b5e6-96231b3b80d8
2015-07-09 02:10:08 +00:00
Mehdi Amini
0e496c884c Make isLegalAddressingMode() taking DataLayout as an argument
Summary:
This change is part of a series of commits dedicated to have a single
DataLayout during compilation by using always the one owned by the
module.

Reviewers: echristo

Subscribers: jholewinski, llvm-commits, rafael, yaron.keren

Differential Revision: http://reviews.llvm.org/D11040

From: Mehdi Amini <mehdi.amini@apple.com>

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@241778 91177308-0d34-0410-b5e6-96231b3b80d8
2015-07-09 02:09:40 +00:00
Mehdi Amini
29a2d864d4 Make TargetLowering::getShiftAmountTy() taking DataLayout as an argument
Summary:
This change is part of a series of commits dedicated to have a single
DataLayout during compilation by using always the one owned by the
module.

Reviewers: echristo

Subscribers: jholewinski, llvm-commits, rafael, yaron.keren

Differential Revision: http://reviews.llvm.org/D11037

From: Mehdi Amini <mehdi.amini@apple.com>

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@241776 91177308-0d34-0410-b5e6-96231b3b80d8
2015-07-09 02:09:20 +00:00
Mehdi Amini
f29cc18dcb Make TargetLowering::getPointerTy() taking DataLayout as an argument
Summary:
This change is part of a series of commits dedicated to have a single
DataLayout during compilation by using always the one owned by the
module.

Reviewers: echristo

Subscribers: jholewinski, ted, yaron.keren, rafael, llvm-commits

Differential Revision: http://reviews.llvm.org/D11028

From: Mehdi Amini <mehdi.amini@apple.com>

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@241775 91177308-0d34-0410-b5e6-96231b3b80d8
2015-07-09 02:09:04 +00:00
Mehdi Amini
966e6ca1ac Make TargetTransformInfo keeping a reference to the Module DataLayout
DataLayout is no longer optional. It was initialized with or without
a DataLayout, and the DataLayout when supplied could have been the
one from the TargetMachine.

Summary:
This change is part of a series of commits dedicated to have a single
DataLayout during compilation by using always the one owned by the
module.

Reviewers: echristo

Subscribers: jholewinski, llvm-commits, rafael, yaron.keren

Differential Revision: http://reviews.llvm.org/D11021

From: Mehdi Amini <mehdi.amini@apple.com>

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@241774 91177308-0d34-0410-b5e6-96231b3b80d8
2015-07-09 02:08:42 +00:00
Daniel Sanders
96fe9196e9 Change the last few internal StringRef triples into Triple objects.
Summary:
This concludes the patch series to eliminate StringRef forms of GNU triples
from the internals of LLVM that began in r239036.

At this point, the StringRef-form of GNU Triples should only be used in the
public API (including IR serialization) and a couple objects that directly
interact with the API (most notably the Module class). The next step is to
replace these Triple objects with the TargetTuple object that will represent
our authoratative/unambiguous internal equivalent to GNU Triples.

Reviewers: rengolin

Subscribers: llvm-commits, jholewinski, ted, rengolin

Differential Revision: http://reviews.llvm.org/D10962

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@241472 91177308-0d34-0410-b5e6-96231b3b80d8
2015-07-06 16:56:07 +00:00
Benjamin Kramer
54b3b4c15e [TargetLowering] StringRefize asm constraint getters.
There is some functional change here because it changes target code from
atoi(3) to StringRef::getAsInteger which has error checking. For valid
constraints there should be no difference.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@241411 91177308-0d34-0410-b5e6-96231b3b80d8
2015-07-05 19:29:18 +00:00
Ranjeet Singh
b0f7871d4e Reverting r241058 because it's causing buildbot failures.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@241061 91177308-0d34-0410-b5e6-96231b3b80d8
2015-06-30 12:32:53 +00:00
Ranjeet Singh
a5106ca54d There are a few places where subtarget features are still
represented by uint64_t, this patch replaces these
usages with the FeatureBitset (std::bitset) type.

Differential Revision: http://reviews.llvm.org/D10542


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@241058 91177308-0d34-0410-b5e6-96231b3b80d8
2015-06-30 11:30:42 +00:00
Ulrich Weigand
01381b0e95 [SystemZ] Only attempt RxSBG optimization for integer types
As pointed out by Justin Bogner (see r240520), SystemZDAGToDAGISel::Select
currently attempts to convert boolean operations into RxSBG even on some
non-integer types (in particular, vector types).  This would not work in
any case, and it happened to trigger undefined behaviour in allOnes.

This patch verifies that we have a (<= 64-bit) integer type before
attempting to perform this optimization.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@240634 91177308-0d34-0410-b5e6-96231b3b80d8
2015-06-25 11:52:36 +00:00
Justin Bogner
cac03419a6 SystemZ: Rephrase this allOnes calculation to avoid UB
This allOnes function hits undefined behaviour if Count is greater
than 64, but we can avoid that and simplify the calculation by just
saturating if such a value is passed in.

This comes up under ubsan becauseRxSBGOperands is sometimes created
with values that are 128 bits wide. Somebody more familiar with this
code should probably look into whether that's expected, as a 64 bit
mask may or may not be appropriate for such types.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@240520 91177308-0d34-0410-b5e6-96231b3b80d8
2015-06-24 05:59:19 +00:00
Justin Bogner
3800e768a2 SystemZ: Avoid left shifting negative values (it's UB)
Found by ubsan.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@240420 91177308-0d34-0410-b5e6-96231b3b80d8
2015-06-23 15:38:24 +00:00
Alexander Kornienko
cd52a7a381 Revert r240137 (Fixed/added namespace ending comments using clang-tidy. NFC)
Apparently, the style needs to be agreed upon first.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@240390 91177308-0d34-0410-b5e6-96231b3b80d8
2015-06-23 09:49:53 +00:00
Alexander Kornienko
cf0db29df2 Fixed/added namespace ending comments using clang-tidy. NFC
The patch is generated using this command:

tools/clang/tools/extra/clang-tidy/tool/run-clang-tidy.py -fix \
  -checks=-*,llvm-namespace-comment -header-filter='llvm/.*|clang/.*' \
  llvm/lib/


Thanks to Eugene Kosov for the original patch!



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@240137 91177308-0d34-0410-b5e6-96231b3b80d8
2015-06-19 15:57:42 +00:00
Chandler Carruth
4d7ed3960c [PM/AA] Remove the Location typedef from the AliasAnalysis class now
that it is its own entity in the form of MemoryLocation, and update all
the callers.

This is an entirely mechanical change. References to "Location" within
AA subclases become "MemoryLocation", and elsewhere
"AliasAnalysis::Location" becomes "MemoryLocation". Hope that helps
out-of-tree folks update.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@239885 91177308-0d34-0410-b5e6-96231b3b80d8
2015-06-17 07:18:54 +00:00
Daniel Sanders
4ddb0ced90 Replace string GNU Triples with llvm::Triple in TargetMachine. NFC.
Summary:
For the moment, TargetMachine::getTargetTriple() still returns a StringRef.

This continues the patch series to eliminate StringRef forms of GNU triples
from the internals of LLVM that began in r239036.

Reviewers: rengolin

Reviewed By: rengolin

Subscribers: ted, llvm-commits, rengolin, jholewinski

Differential Revision: http://reviews.llvm.org/D10362

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@239554 91177308-0d34-0410-b5e6-96231b3b80d8
2015-06-11 19:41:26 +00:00
Ahmed Bougacha
fd83cb21ce [CodeGen] ArrayRef'ize cond/pred in various TII APIs. NFC.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@239553 91177308-0d34-0410-b5e6-96231b3b80d8
2015-06-11 19:30:37 +00:00
Daniel Sanders
f0e3a9c174 Replace string GNU Triples with llvm::Triple in computeDataLayout(). NFC.
Summary:
This continues the patch series to eliminate StringRef forms of GNU triples
from the internals of LLVM that began in r239036.

Reviewers: rengolin

Reviewed By: rengolin

Subscribers: llvm-commits, jfb, rengolin

Differential Revision: http://reviews.llvm.org/D10361

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@239538 91177308-0d34-0410-b5e6-96231b3b80d8
2015-06-11 15:34:59 +00:00
Daniel Sanders
4d13f315d1 Replace string GNU Triples with llvm::Triple in MCSubtargetInfo and create*MCSubtargetInfo(). NFC.
Summary:
This continues the patch series to eliminate StringRef forms of GNU triples
from the internals of LLVM that began in r239036.

Reviewers: rafael

Reviewed By: rafael

Subscribers: rafael, ted, jfb, llvm-commits, rengolin, jholewinski

Differential Revision: http://reviews.llvm.org/D10311


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@239467 91177308-0d34-0410-b5e6-96231b3b80d8
2015-06-10 12:11:26 +00:00
Daniel Sanders
03c060b6d4 Replace string GNU Triples with llvm::Triple in MCAsmBackend subclasses and create*AsmBackend(). NFC.
Summary:
This continues the patch series to eliminate StringRef forms of GNU triples
from the internals of LLVM that began in r239036.

Reviewers: echristo, rafael

Reviewed By: rafael

Subscribers: rafael, llvm-commits, rengolin

Differential Revision: http://reviews.llvm.org/D10243

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@239464 91177308-0d34-0410-b5e6-96231b3b80d8
2015-06-10 10:35:34 +00:00
Matt Arsenault
d99ce2f630 MC: Add target hook to control symbol quoting
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@239370 91177308-0d34-0410-b5e6-96231b3b80d8
2015-06-09 00:31:39 +00:00
Keno Fischer
4332f869bf [InstrInfo] Refactor foldOperandImpl to thread through InsertPt. NFC
Summary:
This was a longstanding FIXME and is a necessary precursor to cases
where foldOperandImpl may have to create more than one instruction
(e.g. to constrain a register class). This is the split out NFC changes from
D6262.

Reviewers: pete, ributzka, uweigand, mcrosier

Reviewed By: mcrosier

Subscribers: mcrosier, ted, llvm-commits

Differential Revision: http://reviews.llvm.org/D10174

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@239336 91177308-0d34-0410-b5e6-96231b3b80d8
2015-06-08 20:09:58 +00:00
Jim Grosbach
bc81286cac MC: Clean up naming in MCObjectWriter. NFC.
s/WriteObject/writeObject/
s/RecordRelocation/recordRelocation/
s/IsSymbolRefDifferenceFullyResolved/isSymbolRefDifferenceFullyResolved/
s/Write8/write8/
s/WriteLE16/writeLE16/
s/WriteLE32/writeLE32/
s/WriteLE64/writeLE64/
s/WriteBE16/writeBE16/
s/WriteBE32/writeBE32/
s/WriteBE64/writeBE64/
s/Write16/write16/
s/Write32/write32/
s/Write64/write64/
s/WriteZeroes/writeZeroes/
s/WriteBytes/writeBytes/

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@239108 91177308-0d34-0410-b5e6-96231b3b80d8
2015-06-04 22:24:41 +00:00
Daniel Sanders
6ff6fc6055 Replace string GNU Triples with llvm::Triple in MCAsmInfo subclasses and create*AsmInfo(). NFC.
Summary:
This is the first of several patches to eliminate StringRef forms of GNU
triples from the internals of LLVM. After this is complete, GNU triples
will be replaced by a more authoratitive representation in the form of
an LLVM TargetTuple.

Reviewers: rengolin

Reviewed By: rengolin

Subscribers: ted, llvm-commits, rengolin, jholewinski

Differential Revision: http://reviews.llvm.org/D10236


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@239036 91177308-0d34-0410-b5e6-96231b3b80d8
2015-06-04 13:12:25 +00:00
Matt Arsenault
5f3a6430d6 Add address space argument to isLegalAddressingMode
This is important because of different addressing modes
depending on the address space for GPU targets.

This only adds the argument, and does not update
any of the uses to provide the correct address space.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@238723 91177308-0d34-0410-b5e6-96231b3b80d8
2015-06-01 05:31:59 +00:00
Jim Grosbach
586c0042da MC: Clean up MCExpr naming. NFC.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@238634 91177308-0d34-0410-b5e6-96231b3b80d8
2015-05-30 01:25:56 +00:00
Matthias Braun
e4603f0daf MachineInstr: Change return value of getOpcode() to unsigned.
This was previously returning int. However there are no negative opcode
numbers and more importantly this was needlessly different from
MCInstrDesc::getOpcode() (which even is the value returned here) and
SDValue::getOpcode()/SDNode::getOpcode().

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@237611 91177308-0d34-0410-b5e6-96231b3b80d8
2015-05-18 20:27:55 +00:00
Jim Grosbach
19696daa21 MC: Clean up method names in MCContext.
The naming was a mish-mash of old and new style. Update to be consistent
with the new. NFC.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@237594 91177308-0d34-0410-b5e6-96231b3b80d8
2015-05-18 18:43:14 +00:00
Pete Cooper
fc9bfcd184 Remove MCAssembler.h include from MCStreamer.h and fix users of MCStreamer.h
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@237483 91177308-0d34-0410-b5e6-96231b3b80d8
2015-05-15 22:19:42 +00:00
Pete Cooper
39aa893201 Remove 3 includes from MCInstrDesc.h and explicitly include them where needed
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@237481 91177308-0d34-0410-b5e6-96231b3b80d8
2015-05-15 21:58:42 +00:00
Jim Grosbach
21a996a0e3 MC: MCCodeGenInfo naming update. NFC.
s/InitMCCodeGenInfo/initMCCodeGenInfo/

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@237471 91177308-0d34-0410-b5e6-96231b3b80d8
2015-05-15 19:13:31 +00:00
Jim Grosbach
251a66ec37 MC: Update MCCodeEmitter naming. NFC.
s/EncodeInstruction/encodeInstruction/

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@237469 91177308-0d34-0410-b5e6-96231b3b80d8
2015-05-15 19:13:16 +00:00
Jim Grosbach
8b22e9c00a MC: Update MCFixup naming. NFC.
s/MCFixup::Create/MCFixup::create/

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@237468 91177308-0d34-0410-b5e6-96231b3b80d8
2015-05-15 19:13:05 +00:00
Jim Grosbach
db703aaedd MC: Modernize MCOperand API naming. NFC.
MCOperand::Create*() methods renamed to MCOperand::create*().

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@237275 91177308-0d34-0410-b5e6-96231b3b80d8
2015-05-13 18:37:00 +00:00
Aaron Ballman
fe78d295da Silencing an MSVC warning: '<<' : result of 32-bit shift implicitly converted to 64 bits (was 64-bit shift intended?); NFC
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@236987 91177308-0d34-0410-b5e6-96231b3b80d8
2015-05-11 12:45:53 +00:00
Saleem Abdulrasool
52a759a24f SystemZ: silence a GCC warning
warning: enumeral and non-enumeral type in conditional expression

Cast the 0 to the appropriate type.  NFC.  Identified by GCC 4.9.2

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@236942 91177308-0d34-0410-b5e6-96231b3b80d8
2015-05-10 00:53:41 +00:00
Matthias Braun
bbff669c18 Change getTargetNodeName() to produce compiler warnings for missing cases, fix them
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@236775 91177308-0d34-0410-b5e6-96231b3b80d8
2015-05-07 21:33:59 +00:00
Ulrich Weigand
88b90e11b4 [SystemZ] Add vector intrinsics
This adds intrinsics to allow access to all of the z13 vector instructions.
Note that instructions whose semantics can be described by standard LLVM IR
do not get any intrinsics.

For each instructions whose semantics *cannot* (fully) be described, we
define an LLVM IR target-specific intrinsic that directly maps to this
instruction.

For instructions that also set the condition code, the LLVM IR intrinsic
returns the post-instruction CC value as a second result.  Instruction
selection will attempt to detect code that compares that CC value against
constants and use the condition code directly instead.

Based on a patch by Richard Sandiford.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@236527 91177308-0d34-0410-b5e6-96231b3b80d8
2015-05-05 19:31:09 +00:00
Ulrich Weigand
e07464832d [SystemZ] Mark v1i128 and v1f128 as unsupported
The ABI specifies that <1 x i128> and <1 x fp128> are supposed to be
passed in vector registers.  We do not yet support those types, and
some infrastructure is missing before we can do so.

In order to prevent accidentally generating code violating the ABI,
this patch adds checks to detect those types and error out if user
code attempts to use them.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@236526 91177308-0d34-0410-b5e6-96231b3b80d8
2015-05-05 19:30:05 +00:00
Ulrich Weigand
538287dea2 [SystemZ] Handle sub-128 vectors
The ABI allows sub-128 vectors to be passed and returned in registers,
with the vector occupying the upper part of a register.  We therefore
want to legalize those types by widening the vector rather than promoting
the elements.

The patch includes some simple tests for sub-128 vectors and also tests
that we can recognize various pack sequences, some of which use sub-128
vectors as temporary results.  One of these forms is based on the pack
sequences generated by llvmpipe when no intrinsics are used.

Signed unpacks are recognized as BUILD_VECTORs whose elements are
individually sign-extended.  Unsigned unpacks can have the equivalent
form with zero extension, but they also occur as shuffles in which some
elements are zero.

Based on a patch by Richard Sandiford.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@236525 91177308-0d34-0410-b5e6-96231b3b80d8
2015-05-05 19:29:21 +00:00
Ulrich Weigand
cf0fa9b9dd [SystemZ] Add CodeGen support for scalar f64 ops in vector registers
The z13 vector facility includes some instructions that operate only on the
high f64 in a v2f64, effectively extending the FP register set from 16
to 32 registers.  It's still better to use the old instructions if the
operands happen to fit though, since the older instructions have a shorter
encoding.

Based on a patch by Richard Sandiford.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@236524 91177308-0d34-0410-b5e6-96231b3b80d8
2015-05-05 19:28:34 +00:00
Ulrich Weigand
878c6281d3 [SystemZ] Add CodeGen support for v4f32
The architecture doesn't really have any native v4f32 operations except
v4f32->v2f64 and v2f64->v4f32 conversions, with only half of the v4f32
elements being used.  Even so, using vector registers for <4 x float>
and scalarising individual operations is much better than generating
completely scalar code, since there's much less register pressure.
It's also more efficient to do v4f32 comparisons by extending to 2
v2f64s, comparing those, then packing the result.

This particularly helps with llvmpipe.

Based on a patch by Richard Sandiford.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@236523 91177308-0d34-0410-b5e6-96231b3b80d8
2015-05-05 19:27:45 +00:00
Ulrich Weigand
1654111384 [SystemZ] Add CodeGen support for v2f64
This adds ABI and CodeGen support for the v2f64 type, which is natively
supported by z13 instructions.

Based on a patch by Richard Sandiford.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@236522 91177308-0d34-0410-b5e6-96231b3b80d8
2015-05-05 19:26:48 +00:00
Ulrich Weigand
aa5c996eda [SystemZ] Add CodeGen support for integer vector types
This the first of a series of patches to add CodeGen support exploiting
the instructions of the z13 vector facility.  This patch adds support
for the native integer vector types (v16i8, v8i16, v4i32, v2i64).

When the vector facility is present, we default to the new vector ABI.
This is characterized by two major differences:
- Vector types are passed/returned in vector registers
  (except for unnamed arguments of a variable-argument list function).
- Vector types are at most 8-byte aligned.

The reason for the choice of 8-byte vector alignment is that the hardware
is able to efficiently load vectors at 8-byte alignment, and the ABI only
guarantees 8-byte alignment of the stack pointer, so requiring any higher
alignment for vectors would require dynamic stack re-alignment code.

However, for compatibility with old code that may use vector types, when
*not* using the vector facility, the old alignment rules (vector types
are naturally aligned) remain in use.

These alignment rules are not only implemented at the C language level
(implemented in clang), but also at the LLVM IR level.  This is done
by selecting a different DataLayout string depending on whether the
vector ABI is in effect or not.

Based on a patch by Richard Sandiford.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@236521 91177308-0d34-0410-b5e6-96231b3b80d8
2015-05-05 19:25:42 +00:00
Ulrich Weigand
1a21909e98 [SystemZ] Add z13 vector facility and MC support
This patch adds support for the z13 processor type and its vector facility,
and adds MC support for all new instructions provided by that facilily.

Apart from defining the new instructions, the main changes are:

- Adding VR128, VR64 and VR32 register classes.
- Making FP64 a subclass of VR64 and FP32 a subclass of VR32.
- Adding a D(V,B) addressing mode for scatter/gather operations
- Adding 1-, 2-, and 3-bit immediate operands for some 4-bit fields.
  Until now all immediate operands have been the same width as the
  underlying field (hence the assert->return change in decode[SU]ImmOperand).

In addition, sys::getHostCPUName is extended to detect running natively
on a z13 machine.

Based on a patch by Richard Sandiford.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@236520 91177308-0d34-0410-b5e6-96231b3b80d8
2015-05-05 19:23:40 +00:00
Quentin Colombet
2f7322b348 [ShrinkWrap] Add (a simplified version) of shrink-wrapping.
This patch introduces a new pass that computes the safe point to insert the
prologue and epilogue of the function.
The interest is to find safe points that are cheaper than the entry and exits
blocks.

As an example and to avoid regressions to be introduce, this patch also
implements the required bits to enable the shrink-wrapping pass for AArch64.


** Context **

Currently we insert the prologue and epilogue of the method/function in the
entry and exits blocks. Although this is correct, we can do a better job when
those are not immediately required and insert them at less frequently executed
places.
The job of the shrink-wrapping pass is to identify such places.


** Motivating example **

Let us consider the following function that perform a call only in one branch of
a if:
define i32 @f(i32 %a, i32 %b)  {
 %tmp = alloca i32, align 4
 %tmp2 = icmp slt i32 %a, %b
 br i1 %tmp2, label %true, label %false

true:
 store i32 %a, i32* %tmp, align 4
 %tmp4 = call i32 @doSomething(i32 0, i32* %tmp)
 br label %false

false:
 %tmp.0 = phi i32 [ %tmp4, %true ], [ %a, %0 ]
 ret i32 %tmp.0
}

On AArch64 this code generates (removing the cfi directives to ease
readabilities):
_f:                                     ; @f
; BB#0:
  stp x29, x30, [sp, #-16]!
  mov  x29, sp
  sub sp, sp, #16             ; =16
  cmp  w0, w1
  b.ge  LBB0_2
; BB#1:                                 ; %true
  stur  w0, [x29, #-4]
  sub x1, x29, #4             ; =4
  mov  w0, wzr
  bl  _doSomething
LBB0_2:                                 ; %false
  mov  sp, x29
  ldp x29, x30, [sp], #16
  ret

With shrink-wrapping we could generate:
_f:                                     ; @f
; BB#0:
  cmp  w0, w1
  b.ge  LBB0_2
; BB#1:                                 ; %true
  stp x29, x30, [sp, #-16]!
  mov  x29, sp
  sub sp, sp, #16             ; =16
  stur  w0, [x29, #-4]
  sub x1, x29, #4             ; =4
  mov  w0, wzr
  bl  _doSomething
  add sp, x29, #16            ; =16
  ldp x29, x30, [sp], #16
LBB0_2:                                 ; %false
  ret

Therefore, we would pay the overhead of setting up/destroying the frame only if
we actually do the call.


** Proposed Solution **

This patch introduces a new machine pass that perform the shrink-wrapping
analysis (See the comments at the beginning of ShrinkWrap.cpp for more details).
It then stores the safe save and restore point into the MachineFrameInfo
attached to the MachineFunction.
This information is then used by the PrologEpilogInserter (PEI) to place the
related code at the right place. This pass runs right before the PEI.

Unlike the original paper of Chow from PLDI’88, this implementation of
shrink-wrapping does not use expensive data-flow analysis and does not need hack
to properly avoid frequently executed point. Instead, it relies on dominance and
loop properties.

The pass is off by default and each target can opt-in by setting the
EnableShrinkWrap boolean to true in their derived class of TargetPassConfig.
This setting can also be overwritten on the command line by using
-enable-shrink-wrap.

Before you try out the pass for your target, make sure you properly fix your
emitProlog/emitEpilog/adjustForXXX method to cope with basic blocks that are not
necessarily the entry block.


** Design Decisions **

1. ShrinkWrap is its own pass right now. It could frankly be merged into PEI but
for debugging and clarity I thought it was best to have its own file.
2. Right now, we only support one save point and one restore point. At some
point we can expand this to several save point and restore point, the impacted
component would then be:
- The pass itself: New algorithm needed.
- MachineFrameInfo: Hold a list or set of Save/Restore point instead of one
  pointer.
- PEI: Should loop over the save point and restore point.
Anyhow, at least for this first iteration, I do not believe this is interesting
to support the complex cases. We should revisit that when we motivating
examples.

Differential Revision: http://reviews.llvm.org/D9210

<rdar://problem/3201744>


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@236507 91177308-0d34-0410-b5e6-96231b3b80d8
2015-05-05 17:38:16 +00:00
Ulrich Weigand
e6cd0c73a7 [SystemZ] Reclassify f32 subregs of f64 registers
At the moment, all subregs defined by the SystemZ target can be modified
independently of the wider register.  E.g. writing to a GR32 does not
change the upper 32 bits of the GR64.  Writing to an FP32 does not change
the lower 32 bits of the FP64.

Hoewver, the upcoming support for the vector extension redefines FP64 as
one half of a V128.  Floating-point operations leave the other half of
a V128 in an unpredictable state, so it's no longer the case that writing
to an FP32 leaves the bits of the underlying register (the V128) alone.
I'd prefer to have separate subreg_ names for this situation, so that
it's obvious at a glance whether we're talking about a subreg that leaves
the other parts of the register alone.

No behavioral change intended.

Patch originally by Richard Sandiford.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@236433 91177308-0d34-0410-b5e6-96231b3b80d8
2015-05-04 17:41:22 +00:00
Ulrich Weigand
7f3a9e28fa [SystemZ] Clean up AsmParser isMem() handling
We know what MemoryKind an operand has at the time we construct it,
so we might as well just record it in an unused part of the structure.
This makes it easier to add scatter/gather addresses later.

No behavioral change intended.

Patch originally by Richard Sandiford.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@236432 91177308-0d34-0410-b5e6-96231b3b80d8
2015-05-04 17:40:53 +00:00
Ulrich Weigand
d9af71b574 [SystemZ] Fix getTargetNodeName
It seems SystemZTargetLowering::getTargetNodeName got out of sync with
some recent changes to the SystemZISD opcode list.  Add back all the
missing opcodes (and re-sort to the same order as SystemISelLowering.h).



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@236430 91177308-0d34-0410-b5e6-96231b3b80d8
2015-05-04 17:39:40 +00:00
Sergey Dmitrouk
1f7a90d793 Reapply r235977 "[DebugInfo] Add debug locations to constant SD nodes"
[DebugInfo] Add debug locations to constant SD nodes

This adds debug location to constant nodes of Selection DAG and updates
all places that create constants to pass debug locations
(see PR13269).

Can't guarantee that all locations are correct, but in a lot of cases choice
is obvious, so most of them should be. At least all tests pass.

Tests for these changes do not cover everything, instead just check it for
SDNodes, ARM and AArch64 where it's easy to get incorrect locations on
constants.

This is not complete fix as FastISel contains workaround for wrong debug
locations, which drops locations from instructions on processing constants,
but there isn't currently a way to use debug locations from constants there
as llvm::Constant doesn't cache it (yet). Although this is a bit different
issue, not directly related to these changes.

Differential Revision: http://reviews.llvm.org/D9084

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@235989 91177308-0d34-0410-b5e6-96231b3b80d8
2015-04-28 14:05:47 +00:00