Commit Graph

2855 Commits

Author SHA1 Message Date
Eric Christopher
4ec858ec4b Have TargetRegisterInfo::getLargestLegalSuperClass take a
MachineFunction argument so that it can look up the subtarget
rather than using a cached one in some Targets.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@231888 91177308-0d34-0410-b5e6-96231b3b80d8
2015-03-10 23:46:01 +00:00
Eric Christopher
597013d371 Remove dead code.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@231883 91177308-0d34-0410-b5e6-96231b3b80d8
2015-03-10 23:22:04 +00:00
Quentin Colombet
7775242da3 [CodeGenPrepare] Refine the cost model provided by the promotion helper.
- Use TargetLowering to check for the actual cost of each extension.
- Provide a factorized method to check for the cost of an extension:
  TargetLowering::isExtFree.
- Provide a virtual method TargetLowering::isExtFreeImpl for targets to be able
  to tune the cost of non-free extensions.

This refactoring offers a better granularity to model what really happens on
different targets.

No performance changes and very few code differences.

Part of <rdar://problem/19267165> 


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@231855 91177308-0d34-0410-b5e6-96231b3b80d8
2015-03-10 21:48:15 +00:00
Mehdi Amini
529919ff31 DataLayout is mandatory, update the API to reflect it with references.
Summary:
Now that the DataLayout is a mandatory part of the module, let's start
cleaning the codebase. This patch is a first attempt at doing that.

This patch is not exactly NFC as for instance some places were passing
a nullptr instead of the DataLayout, possibly just because there was a
default value on the DataLayout argument to many functions in the API.
Even though it is not purely NFC, there is no change in the
validation.

I turned as many pointer to DataLayout to references, this helped
figuring out all the places where a nullptr could come up.

I had initially a local version of this patch broken into over 30
independant, commits but some later commit were cleaning the API and
touching part of the code modified in the previous commits, so it
seemed cleaner without the intermediate state.

Test Plan:

Reviewers: echristo

Subscribers: llvm-commits

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

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@231740 91177308-0d34-0410-b5e6-96231b3b80d8
2015-03-10 02:37:25 +00:00
Matthias Braun
47941aa098 DAGCombiner: Canonicalize select(and/or,x,y) depending on target.
This is based on the following equivalences:
select(C0 & C1, X, Y) <=> select(C0, select(C1, X, Y), Y)
select(C0 | C1, X, Y) <=> select(C0, X, select(C1, X, Y))

Many target cannot perform and/or on the CPU flags and therefore the
right side should be choosen to avoid materializign the i1 flags in an
integer register. If the target can perform this operation efficiently
we normalize to the left form.

Differential Revision: http://reviews.llvm.org/D7622

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@231507 91177308-0d34-0410-b5e6-96231b3b80d8
2015-03-06 19:49:10 +00:00
Bruno Cardoso Lopes
dfc6383227 [AsmPrinter][TLOF] 32-bit MachO support for replacing GOT equivalents
Add MachO 32-bit (i.e. arm and x86) support for replacing global GOT equivalent
symbol accesses. Unlike 64-bit targets, there's no GOTPCREL relocation, and
access through a non_lazy_symbol_pointers section is used instead.

-- before

    _extgotequiv:
       .long _extfoo

    _delta:
       .long _extgotequiv-_delta

-- after

    _delta:
       .long L_extfoo$non_lazy_ptr-_delta

       .section __IMPORT,__pointers,non_lazy_symbol_pointers
    L_extfoo$non_lazy_ptr:
       .indirect_symbol _extfoo
       .long 0

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@231475 91177308-0d34-0410-b5e6-96231b3b80d8
2015-03-06 13:49:05 +00:00
Bruno Cardoso Lopes
66aa390799 [AsmPrinter][TLOF] ARM64 MachO support for replacing GOT equivalents
Follow up r230264 and add ARM64 support for replacing global GOT
equivalent symbol accesses by references to the GOT entry for the final
symbol instead, example:

-- before

   .globl  _foo
  _foo:
   .long   42

   .globl  _gotequivalent
  _gotequivalent:
   .quad   _foo

   .globl  _delta
  _delta:
   .long   _gotequivalent-_delta

-- after

   .globl  _foo
  _foo:
   .long   42

   .globl  _delta
  Ltmp3:
   .long _foo@GOT-Ltmp3

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@231474 91177308-0d34-0410-b5e6-96231b3b80d8
2015-03-06 13:48:45 +00:00
Craig Topper
8ad519fd3c [TableGen] Add support constraining a vector type in a pattern to have a specific element type and for constraining a vector type to have the same number of elements as another vector type. This is useful for AVX512 mask operations so we relate the mask type to the type of the other arguments.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@231356 91177308-0d34-0410-b5e6-96231b3b80d8
2015-03-05 07:11:34 +00:00
JF Bastien
81338a4890 Mutate TargetLowering::shouldExpandAtomicRMWInIR to specifically dictate how AtomicRMWInsts are expanded.
Summary:
In PNaCl, most atomic instructions have their own @llvm.nacl.atomic.* function, each one, with a few exceptions, represents a consistent behaviour across all NaCl-supported targets. Unfortunately, the atomic RMW operations nand, [u]min, and [u]max aren't directly represented by any such @llvm.nacl.atomic.* function. This patch refines shouldExpandAtomicRMWInIR in TargetLowering so that a future `Le32TargetLowering` class can selectively inform the caller how the target desires the atomic RMW instruction to be expanded (ie via load-linked/store-conditional for ARM/AArch64, via cmpxchg for X86/others?, or not at all for Mips) if at all.

This does not represent a behavioural change and as such no tests were added.

Patch by: Richard Diamond.

Reviewers: jfb

Reviewed By: jfb

Subscribers: jfb, aemerson, t.p.northover, llvm-commits

Differential Revision: http://reviews.llvm.org/D7713

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@231250 91177308-0d34-0410-b5e6-96231b3b80d8
2015-03-04 15:47:57 +00:00
Ahmed Bougacha
14593eb417 [X86] Special-case 2x CMOV when custom-inserting.
This lets us avoid a few copies that are otherwise hard to get rid of.
The way this is done is, the custom-inserter looks at the following
instruction for another CMOV, and replaces both at the same time.
A previous version used a new CMOV2 opcode, but the custom inserter
is expected to be able to return a different basic block anyway, which
means it's OK - though far from ideal - to alter that block's contents.
Explicitly document that, in case it ever makes a difference.
Alternatives welcome!

Follow-up to r231045.

rdar://19767934
Closes http://reviews.llvm.org/D8019


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@231046 91177308-0d34-0410-b5e6-96231b3b80d8
2015-03-03 01:21:16 +00:00
Elena Demikhovsky
bf4d9a8aaf Reverted 230471 - gather scatter handling in table gen.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@230892 91177308-0d34-0410-b5e6-96231b3b80d8
2015-03-01 08:23:41 +00:00
Benjamin Kramer
b22e2f9f2a ArrayRefize memory operand folding. NFC.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@230846 91177308-0d34-0410-b5e6-96231b3b80d8
2015-02-28 12:04:00 +00:00
Eric Christopher
acdd4442cb getRegForInlineAsmConstraint wants to use TargetRegisterInfo for
a lookup, pass that in rather than use a naked call to getSubtargetImpl.
This involved passing down and around either a TargetMachine or
TargetRegisterInfo. Update all callers/definitions around the targets
and SelectionDAG.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@230699 91177308-0d34-0410-b5e6-96231b3b80d8
2015-02-26 22:38:43 +00:00
Eric Christopher
a01bc6a59f Remove an argument-less call to getSubtargetImpl from TargetLoweringBase.
This required plumbing a TargetRegisterInfo through computeRegisterProperties
and into findRepresentativeClass which uses it for register class
iteration. This required passing a subtarget into a few target specific
initializations of TargetLowering.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@230583 91177308-0d34-0410-b5e6-96231b3b80d8
2015-02-26 00:00:24 +00:00
Eric Christopher
b97b892db1 Move TargetLoweringBase::getTypeConversion to the .cpp file from
the .h file. It's used in only one place (other than recursively)
and there's no need to include it everywhere.

Saves almost 900k from total llvm object file size.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@230561 91177308-0d34-0410-b5e6-96231b3b80d8
2015-02-25 22:41:30 +00:00
Elena Demikhovsky
4105fd49d4 AVX-512: Gather and Scatter patterns
Gather and scatter instructions additionally write to one of the source operands - mask register.
In this case Gather has 2 destination values - the loaded value and the mask.
Till now we did not support code gen pattern for gather - the instruction was generated from 
intrinsic only and machine node was hardcoded.
When we introduce the masked_gather node, we need to select instruction automatically,
in the standard way.
I added a flag "hasTwoExplicitDefs" that allows to handle 2 destination operands.

(Some code in the X86InstrFragmentsSIMD.td is commented out, just to split one big
patch in many small patches)



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@230471 91177308-0d34-0410-b5e6-96231b3b80d8
2015-02-25 09:46:31 +00:00
Eric Christopher
f8c57a105e Rename UpdateRegAllocHint to match style guidelines.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@230357 91177308-0d34-0410-b5e6-96231b3b80d8
2015-02-24 19:10:57 +00:00
Bruno Cardoso Lopes
6bf5b2b094 [AsmPrinter] Access pointers to globals via pcrel GOT entries
Front-ends could use global unnamed_addr to hold pointers to other
symbols, like @gotequivalent below:

@foo = global i32 42
@gotequivalent = private unnamed_addr constant i32* @foo

@delta = global i32 trunc (i64 sub (i64 ptrtoint (i32** @gotequivalent to i64),
                                    i64 ptrtoint (i32* @delta to i64))
                           to i32)

The global @delta holds a data "PC"-relative offset to @gotequivalent,
an unnamed pointer to @foo. The darwin/x86-64 assembly output for this follows:

 .globl  _foo
_foo:
 .long   42

 .globl  _gotequivalent
_gotequivalent:
 .quad   _foo

 .globl  _delta
_delta:
 .long   _gotequivalent-_delta

Since unnamed_addr indicates that the address is not significant, only
the content, we can optimize the case above by replacing pc-relative
accesses to "GOT equivalent" globals, by a PC relative access to the GOT
entry of the final symbol instead. Therefore, "delta" can contain a pc
relative relocation to foo's GOT entry and we avoid the emission of
"gotequivalent", yielding the assembly code below:

 .globl  _foo
_foo:
 .long   42

 .globl  _delta
_delta:
 .long   _foo@GOTPCREL+4

There are a couple of advantages of doing this: (1) Front-ends that need
to emit a great deal of data to store pointers to external symbols could
save space by not emitting such "got equivalent" globals and (2) IR
constructs combined with this opt opens a way to represent GOT pcrel
relocations by using the LLVM IR, which is something we previously had
no way to express.

Differential Revision: http://reviews.llvm.org/D6922

rdar://problem/18534217

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@230264 91177308-0d34-0410-b5e6-96231b3b80d8
2015-02-23 21:26:18 +00:00
Eric Christopher
308458a98b Rewrite the global merge pass to be subprogram agnostic for now.
It was previously using the subtarget to get values for the global
offset without actually checking each function as it was generating
code. Go ahead and solidify the current behavior and make the
existing FIXMEs more prominent.

As a note the ARM backend previously had a thumb1 and non-thumb1
set of defaults. Only the former was tested so I've changed the
behavior to only use that for now.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@230245 91177308-0d34-0410-b5e6-96231b3b80d8
2015-02-23 19:28:45 +00:00
Chad Rosier
6229219f7e Prevent hoisting fmul from THEN/ELSE to IF if there is fmsub/fmadd opportunity.
This patch adds the isProfitableToHoist API.  For AArch64, we want to prevent a
fmul from being hoisted in cases where it is more profitable to form a
fmsub/fmadd.

Phabricator Review: http://reviews.llvm.org/D7299
Patch by Lawrence Hu <lawrence@codeaurora.org>

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@230241 91177308-0d34-0410-b5e6-96231b3b80d8
2015-02-23 19:15:16 +00:00
Matt Arsenault
4bacfe2095 Add generic fmad DAG node.
This allows sharing of FMA forming combines to work
with instructions that have the same semantics as a separate
multiply and add.

This is expand by default, and only formed post legalization
so it shouldn't have much impact on targets that do not want it.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@230070 91177308-0d34-0410-b5e6-96231b3b80d8
2015-02-20 22:10:33 +00:00
Eric Christopher
c9d0715997 Make the TargetMachine::getSubtarget that takes a Function argument
take a reference to match the getSubtargetImpl that takes a Function
argument.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@229994 91177308-0d34-0410-b5e6-96231b3b80d8
2015-02-20 07:32:59 +00:00
Ahmed Bougacha
953c5c9458 [CodeGen] Use ArrayRef instead of std::vector&. NFC.
The former lets us use SmallVectors.  Do so in ARM and AArch64.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@229925 91177308-0d34-0410-b5e6-96231b3b80d8
2015-02-19 23:13:10 +00:00
Rafael Espindola
3b75cfe179 Add r228939 back with a fix.
The problem in the original patch was not switching back to .text after printing
an eh table.

Original message:

On ELF, put PIC jump tables in a non executable section.

Fixes PR22558.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@229586 91177308-0d34-0410-b5e6-96231b3b80d8
2015-02-17 23:34:51 +00:00
Rafael Espindola
e0a2541eb7 Add r228980 back.
Add support for having multiple sections with the same name and comdat.

Using this in combination with -ffunction-sections allows LLVM to output a .o
file with mulitple sections named .text. This saves space by avoiding long
unique names of the form .text.<C++ mangled name>.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@229541 91177308-0d34-0410-b5e6-96231b3b80d8
2015-02-17 20:48:01 +00:00
Andrew Trick
4f7d60c1ea AArch64: Safely handle the incoming sret call argument.
This adds a safe interface to the machine independent InputArg struct
for accessing the index of the original (IR-level) argument. When a
non-native return type is lowered, we generate the hidden
machine-level sret argument on-the-fly. Before this fix, we were
representing this argument as OrigArgIndex == 0, which is an outright
lie. In particular this crashed in the AArch64 backend where we
actually try to access the type of the original argument.

Now we use a sentinel value for machine arguments that have no
original argument index. AArch64, ARM, Mips, and PPC now check for this
case before accessing the original argument.

Fixes <rdar://19792160> Null pointer assertion in AArch64TargetLowering

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@229413 91177308-0d34-0410-b5e6-96231b3b80d8
2015-02-16 18:10:47 +00:00
Aaron Ballman
66981fe208 Removing LLVM_DELETED_FUNCTION, as MSVC 2012 was the last reason for requiring the macro. NFC; LLVM edition.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@229340 91177308-0d34-0410-b5e6-96231b3b80d8
2015-02-15 22:54:22 +00:00
Matthias Braun
821ec14add Revert "On ELF, put PIC jump tables in a non executable section."
This reverts commit r228939.

The commit broke something in the output of exception handling tables on
darwin x86-64.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@229203 91177308-0d34-0410-b5e6-96231b3b80d8
2015-02-14 01:16:54 +00:00
Chandler Carruth
00ae03a747 Revert a series of commits starting at r228886 which is triggering some
regressions for LLDB on Linux. Rafael indicated on lldb-dev that we
should just go ahead and revert these but that he wasn't at a computer.
The patches backed out are as follows:

r228980: Add support for having multiple sections with the name and ...
r228889: Invert the section relocation map.
r228888: Use the existing SymbolTableIndex intsead of doing a lookup.
r228886: Create the Section -> Rel Section map when it is first needed.

These patches look pretty nice to me, so hoping its not too hard to get
them re-instated. =D

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@229080 91177308-0d34-0410-b5e6-96231b3b80d8
2015-02-13 07:52:39 +00:00
Rafael Espindola
2fa06b171b Add support for having multiple sections with the same name and comdat.
Using this in combination with -ffunction-sections allows LLVM to output a .o
file with mulitple sections named .text. This saves space by avoiding long
unique names of the form .text.<C++ mangled name>.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@228980 91177308-0d34-0410-b5e6-96231b3b80d8
2015-02-12 23:29:51 +00:00
Rafael Espindola
8093f4b9bb Remove mostly unused setters.
Most of the code was setting the TargetOptions directly.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@228961 91177308-0d34-0410-b5e6-96231b3b80d8
2015-02-12 21:16:34 +00:00
Rafael Espindola
c3c5d7c2d6 On ELF, put PIC jump tables in a non executable section.
Fixes PR22558.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@228939 91177308-0d34-0410-b5e6-96231b3b80d8
2015-02-12 17:46:49 +00:00
Rafael Espindola
8eeedf74d3 Put each jump table in an independent section if the function is too.
This allows the linker to GC both, fixing pr22557.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@228937 91177308-0d34-0410-b5e6-96231b3b80d8
2015-02-12 17:16:46 +00:00
Ahmed Bougacha
ec35069525 [CodeGen] Add hook/combine to form vector extloads, enabled on X86.
The combine that forms extloads used to be disabled on vector types,
because "None of the supported targets knows how to perform load and
sign extend on vectors in one instruction."

That's not entirely true, since at least SSE4.1 X86 knows how to do
those sextloads/zextloads (with PMOVS/ZX).
But there are several aspects to getting this right.
First, vector extloads are controlled by a profitability callback.
For instance, on ARM, several instructions have folded extload forms,
so it's not always beneficial to create an extload node (and trying to
match extloads is a whole 'nother can of worms).

The interesting optimization enables folding of s/zextloads to illegal
(splittable) vector types, expanding them into smaller legal extloads.

It's not ideal (it introduces some legalization-like behavior in the
combine) but it's better than the obvious alternative: form illegal
extloads, and later try to split them up.  If you do that, you might
generate extloads that can't be split up, but have a valid ext+load
expansion.  At vector-op legalization time, it's too late to generate
this kind of code, so you end up forced to scalarize. It's better to
just avoid creating egregiously illegal nodes.

This optimization is enabled unconditionally on X86.

Note that the splitting combine is happy with "custom" extloads. As
is, this bypasses the actual custom lowering, and just unrolls the
extload. But from what I've seen, this is still much better than the
current custom lowering, which does some kind of unrolling at the end
anyway (see for instance load_sext_4i8_to_4i64 on SSE2, and the added
FIXME).

Also note that the existing combine that forms extloads is now also
enabled on legal vectors.  This doesn't have a big effect on X86
(because sext+load is usually combined to sext_inreg+aextload).
On ARM it fires on some rare occasions; that's for a separate commit.

Differential Revision: http://reviews.llvm.org/D6904


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@228325 91177308-0d34-0410-b5e6-96231b3b80d8
2015-02-05 18:31:02 +00:00
Ahmed Bougacha
2e485786c7 [CodeGen] Add isLoadExtLegalOrCustom helper to TargetLowering.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@228322 91177308-0d34-0410-b5e6-96231b3b80d8
2015-02-05 18:15:59 +00:00
Matt Arsenault
0ac74cc4e3 Add addrspacecast node to tablegen
The node is still defined oddly so that the
address spaces are not operands and not accessible
from tablegen, but as-is this can now be used to write
a ComplexPattern with an addrspacecast root node.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@228270 91177308-0d34-0410-b5e6-96231b3b80d8
2015-02-05 03:35:34 +00:00
Eric Christopher
b3f0a42d00 Only access TLOF via the TargetMachine, not TargetLowering.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@227949 91177308-0d34-0410-b5e6-96231b3b80d8
2015-02-03 07:22:52 +00:00
Eric Christopher
aa6be3f734 Remove unnecessary forward declaration.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@227813 91177308-0d34-0410-b5e6-96231b3b80d8
2015-02-02 17:38:40 +00:00
Michael Kuperstein
acd5f13c88 [X86] Convert esp-relative movs of function arguments to pushes, step 2
This moves the transformation introduced in r223757 into a separate MI pass.
This allows it to cover many more cases (not only cases where there must be a 
reserved call frame), and perform rudimentary call folding. It still doesn't 
have a heuristic, so it is enabled only for optsize/minsize, with stack 
alignment <= 8, where it ought to be a fairly clear win.

(Re-commit of r227728)

Differential Revision: http://reviews.llvm.org/D6789


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@227752 91177308-0d34-0410-b5e6-96231b3b80d8
2015-02-01 16:56:04 +00:00
Michael Kuperstein
5b61b8f53c Revert r227728 due to bad line endings.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@227746 91177308-0d34-0410-b5e6-96231b3b80d8
2015-02-01 16:15:07 +00:00
Chandler Carruth
6e89e1316a [multiversion] Switch all of the targets over to use the
TargetIRAnalysis access path directly rather than implementing getTTI.

This even removes getTTI from the interface. It's more efficient for
each target to just register a precise callback that creates their
specific TTI.

As part of this, all of the targets which are building their subtargets
individually per-function now build their TTI instance with the function
and thus look up the correct subtarget and cache it. NVPTX, R600, and
XCore currently don't leverage this functionality, but its trivial for
them to add it now.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@227735 91177308-0d34-0410-b5e6-96231b3b80d8
2015-02-01 13:20:00 +00:00
Michael Kuperstein
59d9986259 [X86] Convert esp-relative movs of function arguments to pushes, step 2
This moves the transformation introduced in r223757 into a separate MI pass.
This allows it to cover many more cases (not only cases where there must be a 
reserved call frame), and perform rudimentary call folding. It still doesn't 
have a heuristic, so it is enabled only for optsize/minsize, with stack 
alignment <= 8, where it ought to be a fairly clear win.

Differential Revision: http://reviews.llvm.org/D6789

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@227728 91177308-0d34-0410-b5e6-96231b3b80d8
2015-02-01 11:44:44 +00:00
Chandler Carruth
7724e8efa2 [PM] Port TTI to the new pass manager, introducing a TargetIRAnalysis to
produce it.

This adds a function to the TargetMachine that produces this analysis
via a callback for each function. This in turn faves the way to produce
a *different* TTI per-function with the correct subtarget cached.

I've also done the necessary wiring in the opt tool to thread the target
machine down and make it available to the pass registry so that we can
construct this analysis from a target machine when available.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@227721 91177308-0d34-0410-b5e6-96231b3b80d8
2015-02-01 10:11:22 +00:00
Chandler Carruth
1937233a22 [PM] Switch the TargetMachine interface from accepting a pass manager
base which it adds a single analysis pass to, to instead return the type
erased TargetTransformInfo object constructed for that TargetMachine.

This removes all of the pass variants for TTI. There is now a single TTI
*pass* in the Analysis layer. All of the Analysis <-> Target
communication is through the TTI's type erased interface itself. While
the diff is large here, it is nothing more that code motion to make
types available in a header file for use in a different source file
within each target.

I've tried to keep all the doxygen comments and file boilerplate in line
with this move, but let me know if I missed anything.

With this in place, the next step to making TTI work with the new pass
manager is to introduce a really simple new-style analysis that produces
a TTI object via a callback into this routine on the target machine.
Once we have that, we'll have the building blocks necessary to accept
a function argument as well.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@227685 91177308-0d34-0410-b5e6-96231b3b80d8
2015-01-31 11:17:59 +00:00
Chandler Carruth
a6a87b595d [PM] Change the core design of the TTI analysis to use a polymorphic
type erased interface and a single analysis pass rather than an
extremely complex analysis group.

The end result is that the TTI analysis can contain a type erased
implementation that supports the polymorphic TTI interface. We can build
one from a target-specific implementation or from a dummy one in the IR.

I've also factored all of the code into "mix-in"-able base classes,
including CRTP base classes to facilitate calling back up to the most
specialized form when delegating horizontally across the surface. These
aren't as clean as I would like and I'm planning to work on cleaning
some of this up, but I wanted to start by putting into the right form.

There are a number of reasons for this change, and this particular
design. The first and foremost reason is that an analysis group is
complete overkill, and the chaining delegation strategy was so opaque,
confusing, and high overhead that TTI was suffering greatly for it.
Several of the TTI functions had failed to be implemented in all places
because of the chaining-based delegation making there be no checking of
this. A few other functions were implemented with incorrect delegation.
The message to me was very clear working on this -- the delegation and
analysis group structure was too confusing to be useful here.

The other reason of course is that this is *much* more natural fit for
the new pass manager. This will lay the ground work for a type-erased
per-function info object that can look up the correct subtarget and even
cache it.

Yet another benefit is that this will significantly simplify the
interaction of the pass managers and the TargetMachine. See the future
work below.

The downside of this change is that it is very, very verbose. I'm going
to work to improve that, but it is somewhat an implementation necessity
in C++ to do type erasure. =/ I discussed this design really extensively
with Eric and Hal prior to going down this path, and afterward showed
them the result. No one was really thrilled with it, but there doesn't
seem to be a substantially better alternative. Using a base class and
virtual method dispatch would make the code much shorter, but as
discussed in the update to the programmer's manual and elsewhere,
a polymorphic interface feels like the more principled approach even if
this is perhaps the least compelling example of it. ;]

Ultimately, there is still a lot more to be done here, but this was the
huge chunk that I couldn't really split things out of because this was
the interface change to TTI. I've tried to minimize all the other parts
of this. The follow up work should include at least:

1) Improving the TargetMachine interface by having it directly return
   a TTI object. Because we have a non-pass object with value semantics
   and an internal type erasure mechanism, we can narrow the interface
   of the TargetMachine to *just* do what we need: build and return
   a TTI object that we can then insert into the pass pipeline.
2) Make the TTI object be fully specialized for a particular function.
   This will include splitting off a minimal form of it which is
   sufficient for the inliner and the old pass manager.
3) Add a new pass manager analysis which produces TTI objects from the
   target machine for each function. This may actually be done as part
   of #2 in order to use the new analysis to implement #2.
4) Work on narrowing the API between TTI and the targets so that it is
   easier to understand and less verbose to type erase.
5) Work on narrowing the API between TTI and its clients so that it is
   easier to understand and less verbose to forward.
6) Try to improve the CRTP-based delegation. I feel like this code is
   just a bit messy and exacerbating the complexity of implementing
   the TTI in each target.

Many thanks to Eric and Hal for their help here. I ended up blocked on
this somewhat more abruptly than I expected, and so I appreciate getting
it sorted out very quickly.

Differential Revision: http://reviews.llvm.org/D7293

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@227669 91177308-0d34-0410-b5e6-96231b3b80d8
2015-01-31 03:43:40 +00:00
Eric Christopher
9003c8d02f Remove the last vestiges of resetOperationActions.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@227648 91177308-0d34-0410-b5e6-96231b3b80d8
2015-01-31 00:21:17 +00:00
Chandler Carruth
df3bf19853 [PM] Remove two very old and dead forward declarations for the prior
incarnation of target transform info.

This is in preparation for starting to redesign TTI to be amenable to
the new PM world.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@227525 91177308-0d34-0410-b5e6-96231b3b80d8
2015-01-30 00:41:44 +00:00
Eric Christopher
28f4510b4c Remove extraneous period.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@227155 91177308-0d34-0410-b5e6-96231b3b80d8
2015-01-27 01:01:34 +00:00
Eric Christopher
04bcc11905 Move DataLayout back to the TargetMachine from TargetSubtargetInfo
derived classes.

Since global data alignment, layout, and mangling is often based on the
DataLayout, move it to the TargetMachine. This ensures that global
data is going to be layed out and mangled consistently if the subtarget
changes on a per function basis. Prior to this all targets(*) have
had subtarget dependent code moved out and onto the TargetMachine.

*One target hasn't been migrated as part of this change: R600. The
R600 port has, as a subtarget feature, the size of pointers and
this affects global data layout. I've currently hacked in a FIXME
to enable progress, but the port needs to be updated to either pass
the 64-bitness to the TargetMachine, or fix the DataLayout to
avoid subtarget dependent features.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@227113 91177308-0d34-0410-b5e6-96231b3b80d8
2015-01-26 19:03:15 +00:00
Chandler Carruth
bda134910a [PM] Move TargetLibraryInfo into the Analysis library.
While the term "Target" is in the name, it doesn't really have to do
with the LLVM Target library -- this isn't an abstraction which LLVM
targets generally need to implement or extend. It has much more to do
with modeling the various runtime libraries on different OSes and with
different runtime environments. The "target" in this sense is the more
general sense of a target of cross compilation.

This is in preparation for porting this analysis to the new pass
manager.

No functionality changed, and updates inbound for Clang and Polly.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@226078 91177308-0d34-0410-b5e6-96231b3b80d8
2015-01-15 02:16:27 +00:00