Commit Graph

1547 Commits

Author SHA1 Message Date
Mehdi Amini
15e1e7f179 Remove access to the DataLayout in the TargetMachine
Summary:
Replace getDataLayout() with a createDataLayout() method to make
explicit that it is intended to create a DataLayout only and not
accessing it for other purpose.

This change is the last 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/D11103

(cherry picked from commit 5609fc56bca971e5a7efeaa6ca4676638eaec5ea)

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

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@243114 91177308-0d34-0410-b5e6-96231b3b80d8
2015-07-24 16:04:22 +00:00
Mehdi Amini
26be214232 Revert "Remove access to the DataLayout in the TargetMachine"
This reverts commit 0f720d984f.

It breaks clang too badly, I need to prepare a proper patch for clang
first.

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

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@243089 91177308-0d34-0410-b5e6-96231b3b80d8
2015-07-24 03:36:55 +00:00
Mehdi Amini
0f720d984f Remove access to the DataLayout in the TargetMachine
Summary:
Replace getDataLayout() with a createDataLayout() method to make
explicit that it is intended to create a DataLayout only and not
accessing it for other purpose.

This change is the last 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/D11103

(cherry picked from commit 5609fc56bca971e5a7efeaa6ca4676638eaec5ea)

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

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@243083 91177308-0d34-0410-b5e6-96231b3b80d8
2015-07-24 01:44:39 +00:00
Mehdi Amini
9c5961b7ba Move most user of TargetMachine::getDataLayout to the Module one
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.

This patch is quite boring overall, except for some uglyness in
ASMPrinter which has a getDataLayout function but has some clients
that use it without a Module (llmv-dsymutil, llvm-dwarfdump), so
some methods are taking a DataLayout as parameter.

Reviewers: echristo

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

Differential Revision: http://reviews.llvm.org/D11090

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

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@242386 91177308-0d34-0410-b5e6-96231b3b80d8
2015-07-16 06:11:10 +00:00
Matthias Braun
2addf067a2 MachineRegisterInfo: Remove UsedPhysReg infrastructure
We have a detailed def/use lists for every physical register in
MachineRegisterInfo anyway, so there is little use in maintaining an
additional bitset of which ones are used.

Removing it frees us from extra book keeping. This simplifies
VirtRegMap.

Differential Revision: http://reviews.llvm.org/D10911

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@242173 91177308-0d34-0410-b5e6-96231b3b80d8
2015-07-14 17:52:07 +00:00
Matthias Braun
a36268215f PrologEpilogInserter: Rewrite API to determine callee save regsiters.
This changes TargetFrameLowering::processFunctionBeforeCalleeSavedScan():

- Rename the function to determineCalleeSaves()
- Pass a bitset of callee saved registers by reference, thus avoiding
  the function-global PhysRegUsed bitset in MachineRegisterInfo.
- Without PhysRegUsed the implementation is fine tuned to not save
  physcial registers which are only read but never modified.

Related to rdar://21539507

Differential Revision: http://reviews.llvm.org/D10909

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@242165 91177308-0d34-0410-b5e6-96231b3b80d8
2015-07-14 17:17:13 +00:00
Duncan P. N. Exon Smith
16859aa242 MC: Remove MCSubtargetInfo() default constructor
Force all creators of `MCSubtargetInfo` to immediately initialize it,
merging the default constructor and the initializer into an initializing
constructor.  Besides cleaning up the code a little, this makes it clear
that the initializer is never called again later.

Out-of-tree backends need a trivial change: instead of calling:

    auto *X = new MCSubtargetInfo();
    InitXYZMCSubtargetInfo(X, ...);
    return X;

they should call:

    return createXYZMCSubtargetInfoImpl(...);

There's no real functionality change here.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@241957 91177308-0d34-0410-b5e6-96231b3b80d8
2015-07-10 22:43:42 +00:00
Mehdi Amini
cdc323b2b7 Re-instate the EVT parameter to getScalarShiftAmountTy() for OOT user
A documentation for this function would be nice by the way.

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

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@241807 91177308-0d34-0410-b5e6-96231b3b80d8
2015-07-09 15:12:23 +00:00
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
691b2ff11e Remove getDataLayout() from TargetLowering
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: yaron.keren, rafael, llvm-commits, jholewinski

Differential Revision: http://reviews.llvm.org/D11042

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

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@241779 91177308-0d34-0410-b5e6-96231b3b80d8
2015-07-09 02:09:52 +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
James Y Knight
8eb1aaac9c [SPARC] Cleanup handling of the Y/ASR registers.
- Implement copying ASR to/from GPR regs.
- Mark ASRs as non-allocatable, so it won't try to arbitrarily use
  them inappropriately.
- Instead of inserting explicit WRASR/RDASR nodes in the MUL/DIV
  routines, just do normal register copies.
- Also...mark div as using Y, not just writing it.

Added a test case with some code which previously died with an
assertion failure (with -O0), or produced wrong code (otherwise).

(Third time's the charm?)

Differential Revision: http://reviews.llvm.org/D10401

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@241686 91177308-0d34-0410-b5e6-96231b3b80d8
2015-07-08 16:25:12 +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
James Y Knight
067b86fcab [Sparc] Add more instruction aliases.
These are mostly from the chart in the SparcV8 spec, section "A.3
Synthetic Instructions".

Differential Revision: http://reviews.llvm.org/D9834

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@241461 91177308-0d34-0410-b5e6-96231b3b80d8
2015-07-06 16:01:07 +00:00
James Y Knight
d32974f9dc [Sparc] Add support for flush instruction.
Differential Revision: http://reviews.llvm.org/D9833

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@241460 91177308-0d34-0410-b5e6-96231b3b80d8
2015-07-06 16:01:04 +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
James Y Knight
bcc1a5c01a [Sparc] Rearrange SparcInstrInfo, no change.
Move some instructions into order of sections in the spec, as the rest
already were.

Differential Revision: http://reviews.llvm.org/D9102

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@241163 91177308-0d34-0410-b5e6-96231b3b80d8
2015-07-01 14:38:07 +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
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
James Y Knight
d280420ee9 [SPARC] Repair GOT references to internal symbols.
They had been getting emitted as a section + offset reference, which
is bogus since the value needs to be the offset within the GOT, not
the actual address of the symbol's object.

Differential Revision: http://reviews.llvm.org/D10441

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@240020 91177308-0d34-0410-b5e6-96231b3b80d8
2015-06-18 15:05:15 +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
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
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
Benjamin Kramer
7ec7c7d865 Replace custom fixed endian to raw_ostream emission with EndianStream.
Less code, clearer and more efficient. No functionality change intended.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@239040 91177308-0d34-0410-b5e6-96231b3b80d8
2015-06-04 15:03:02 +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
Rafael Espindola
569f382a46 Merge MCELF.h into MCSymbolELF.h.
Now that we have a dedicated type for ELF symbol, these helper functions can
become member function of MCSymbolELF.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@238864 91177308-0d34-0410-b5e6-96231b3b80d8
2015-06-02 20:38:46 +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
Rafael Espindola
5b68a837c7 Pass MCSymbols to the helper functions in MCELF.h.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@238596 91177308-0d34-0410-b5e6-96231b3b80d8
2015-05-29 18:47:23 +00:00
Michael Kuperstein
d714fcf5c8 Use std::bitset for SubtargetFeatures.
Previously, subtarget features were a bitfield with the underlying type being uint64_t. 
Since several targets (X86 and ARM, in particular) have hit or were very close to hitting this bound, switching the features to use a bitset.
No functional change.

The first several times this was committed (e.g. r229831, r233055), it caused several buildbot failures.
Apparently the reason for most failures was both clang and gcc's inability to deal with large numbers (> 10K) of bitset constructor calls in tablegen-generated initializers of instruction info tables. 
This should now be fixed.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@238192 91177308-0d34-0410-b5e6-96231b3b80d8
2015-05-26 10:47:10 +00:00
Rafael Espindola
7521964d28 Move alignment from MCSectionData to MCSection.
This starts merging MCSection and MCSectionData.

There are a few issues with the current split between MCSection and
MCSectionData.

* It optimizes the the not as important case. We want the production
of .o files to be really fast, but the split puts the information used
for .o emission in a separate data structure.

* The ELF/COFF/MachO hierarchy is not represented in MCSectionData,
leading to some ad-hoc ways to represent the various flags.

* It makes it harder to remember where each item is.

The attached patch starts merging the two by moving the alignment from
MCSectionData to MCSection.

Most of the patch is actually just dropping 'const', since
MCSectionData is mutable, but MCSection was not.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@237936 91177308-0d34-0410-b5e6-96231b3b80d8
2015-05-21 19:20:38 +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
James Y Knight
ccafe05df1 Sparc: support the "set" synthetic instruction.
This pseudo-instruction expands into 'sethi' and 'or' instructions,
or, just one of them, if the other isn't necessary for a given value.

Differential Revision: http://reviews.llvm.org/D9089

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@237585 91177308-0d34-0410-b5e6-96231b3b80d8
2015-05-18 16:43:33 +00:00
James Y Knight
1467a41471 Sparc: Support PSR, TBR, WIM read/write instructions.
Differential Revision: http://reviews.llvm.org/D8971

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@237582 91177308-0d34-0410-b5e6-96231b3b80d8
2015-05-18 16:38:47 +00:00
James Y Knight
ee058202fa Sparc: Add the "alternate address space" load/store instructions.
- Adds support for the asm syntax, which has an immediate integer
  "ASI" (address space identifier) appearing after an address, before
  a comma.

- Adds the various-width load, store, and swap in alternate address
  space instructions. (ldsba, ldsha, lduba, lduha, lda, stba, stha,
  sta, swapa)

This does not attempt to hook these instructions up to pointer address
spaces in LLVM, although that would probably be a reasonable thing to
do in the future.

Differential Revision: http://reviews.llvm.org/D8904

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@237581 91177308-0d34-0410-b5e6-96231b3b80d8
2015-05-18 16:35:04 +00:00
James Y Knight
f272788a95 Add support for the Sparc implementation-defined "ASR" registers.
(Note that register "Y" is essentially just ASR0).

Also added some test cases for divide and multiply, which had none before.

Differential Revision: http://reviews.llvm.org/D8670

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@237580 91177308-0d34-0410-b5e6-96231b3b80d8
2015-05-18 16:29:48 +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
Michael Kuperstein
66112dd7f8 Reverting r237234, "Use std::bitset for SubtargetFeatures"
The buildbots are still not satisfied.
MIPS and ARM are failing (even though at least MIPS was expected to pass).


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@237245 91177308-0d34-0410-b5e6-96231b3b80d8
2015-05-13 10:28:46 +00:00
Michael Kuperstein
1336daad86 Use std::bitset for SubtargetFeatures
Previously, subtarget features were a bitfield with the underlying type being uint64_t. 
Since several targets (X86 and ARM, in particular) have hit or were very close to hitting this bound, switching the features to use a bitset.
No functional change.

The first two times this was committed (r229831, r233055), it caused several buildbot failures. 
At least some of the ARM and MIPS ones were due to gcc/binutils issues, and should now be fixed.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@237234 91177308-0d34-0410-b5e6-96231b3b80d8
2015-05-13 08:27:08 +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
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