Commit Graph

28 Commits

Author SHA1 Message Date
Mehdi Amini a28d91d81b 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>
llvm-svn: 231740
2015-03-10 02:37:25 +00:00
Tom Stellard eea3f70432 R600/SI: Fix bug in TTI loop unrolling preferences
We should be setting UnrollingPreferences::MaxCount to MAX_UINT instead
of UnrollingPreferences::Count.

Count is a 'forced unrolling factor', while MaxCount sets an upper
limit to the unrolling factor.

Setting Count to MAX_UINT was causing the loop in the testcase to be
unrolled 15 times, when it only had a maximum of 4 iterations.

llvm-svn: 228303
2015-02-05 15:32:18 +00:00
Chandler Carruth ab5cb36c40 [multiversion] Remove the function parameter from the unrolling
preferences interface on TTI now that all of TTI is per-function.

llvm-svn: 227741
2015-02-01 14:31:23 +00:00
Chandler Carruth 93dcdc47db [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.

llvm-svn: 227685
2015-01-31 11:17:59 +00:00
Chandler Carruth 705b185f90 [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

llvm-svn: 227669
2015-01-31 03:43:40 +00:00
Jingyue Wu a41cf018b8 Fix broken doxygen annotations, NFC
llvm-svn: 221801
2014-11-12 18:25:06 +00:00
Eric Christopher d85ffb1fc0 Add a new pass FunctionTargetTransformInfo. This pass serves as a
shim between the TargetTransformInfo immutable pass and the Subtarget
via the TargetMachine and Function. Migrate a single call from
BasicTargetTransformInfo as an example and provide shims where TargetMachine
begins taking a Function to determine the subtarget.

No functional change.

llvm-svn: 218004
2014-09-18 00:34:14 +00:00
Sanjay Patel b653de1ada Rename getMaximumUnrollFactor -> getMaxInterleaveFactor; also rename option names controlling this variable.
"Unroll" is not the appropriate name for this variable. Clang already uses 
the term "interleave" in pragmas and metadata for this.

Differential Revision: http://reviews.llvm.org/D5066

llvm-svn: 217528
2014-09-10 17:58:16 +00:00
Eric Christopher d913448b38 Remove the TargetMachine forwards for TargetSubtargetInfo based
information and update all callers. No functional change.

llvm-svn: 214781
2014-08-04 21:25:23 +00:00
Matt Arsenault c824458e81 R600/SI: Allow partial unrolling and increase thresholds.
llvm-svn: 213985
2014-07-25 23:02:42 +00:00
Matt Arsenault 1c407fb5a3 Revert accidentally committed r213459
llvm-svn: 213461
2014-07-19 19:17:33 +00:00
Matt Arsenault b38677ee2f XXX - Increase unroll threshold
llvm-svn: 213459
2014-07-19 19:16:34 +00:00
Matt Arsenault a93441fe9c R600: Implement a few simple TTI queries.
I'm not sure if these have any effect right now.

llvm-svn: 213455
2014-07-19 18:15:16 +00:00
Matt Arsenault 3dd43fc75d R600: Implement TTI:getPopcntSupport
The test is just copied from X86, and I don't know of a better
way to test it.

llvm-svn: 213351
2014-07-18 06:07:13 +00:00
Matt Arsenault ac6e39cf3b Use range for
llvm-svn: 213230
2014-07-17 06:19:06 +00:00
Matt Arsenault 5e2b0f51e7 R600: Short circuit alloca check if address space isn't private.
Skip calling GetUnderlyingObject in cases where it obviously
isn't from an alloca. This should only be a compile time improvement.

llvm-svn: 213229
2014-07-17 06:13:41 +00:00
Craig Topper 5656db4a8b [C++11] Add 'override' keywords and remove 'virtual'. Additionally add 'final' and leave 'virtual' on some methods that are marked virtual without overriding anything and have no obvious overrides themselves. R600 edition
llvm-svn: 207503
2014-04-29 07:57:24 +00:00
Craig Topper 062a2baef0 [C++] Use 'nullptr'. Target edition.
llvm-svn: 207197
2014-04-25 05:30:21 +00:00
Chandler Carruth 84e68b2994 [Modules] Fix potential ODR violations by sinking the DEBUG_TYPE
definition below all of the header #include lines, lib/Target/...
edition.

llvm-svn: 206842
2014-04-22 02:41:26 +00:00
Matt Arsenault 5e1e4316c4 Fix tabs
llvm-svn: 205648
2014-04-04 20:13:08 +00:00
Chandler Carruth aee3ca6cfd [TTI] There is actually no realistic way to pop TTI implementations off
the stack of the analysis group because they are all immutable passes.
This is made clear by Craig's recent work to use override
systematically -- we weren't overriding anything for 'finalizePass'
because there is no such thing.

This is kind of a lame restriction on the API -- we can no longer push
and pop things, we just set up the stack and run. However, I'm not
invested in building some better solution on top of the existing
(terrifying) immutable pass and legacy pass manager.

llvm-svn: 203437
2014-03-10 02:45:14 +00:00
Craig Topper 73156025e0 Switch all uses of LLVM_OVERRIDE to just use 'override' directly.
llvm-svn: 202621
2014-03-02 09:09:27 +00:00
Craig Topper 77dfe45f81 Switch all uses of LLVM_FINAL to just use 'final', and remove the macro.
llvm-svn: 202618
2014-03-02 08:08:51 +00:00
Tom Stellard fd0d86c322 R600: Don't unconditionally unroll loops with private memory accesses
This causes the size of the scrypt kernel to explode and eats all the
memory on some systems.

llvm-svn: 202195
2014-02-25 21:36:21 +00:00
Juergen Ributzka 3e752e7af9 Add final and owerride keywords to TargetTransformInfo's subclasses.
llvm-svn: 200021
2014-01-24 18:22:59 +00:00
Tom Stellard 8cce9bdf17 R600: Unconditionally unroll loops that contain GEPs with alloca pointers
Implement the getUnrollingPreferences() function for
AMDGPUTargetTransformInfo so that loops that do address calculations
on pointers derived from alloca are unconditionally unrolled.

Unrolling these loops makes it more likely that SROA will be able to
eliminate the allocas, which is a big win for R600 since memory
allocated by alloca (private memory) is really slow.

llvm-svn: 199916
2014-01-23 18:49:28 +00:00
Chandler Carruth 8a8cd2bab9 Re-sort all of the includes with ./utils/sort_includes.py so that
subsequent changes are easier to review. About to fix some layering
issues, and wanted to separate out the necessary churn.

Also comment and sink the include of "Windows.h" in three .inc files to
match the usage in Memory.inc.

llvm-svn: 198685
2014-01-07 11:48:04 +00:00
Tom Stellard 8b1e021e85 SimplifyCFG: Use parallel-and and parallel-or mode to consolidate branch conditions
Merge consecutive if-regions if they contain identical statements.
Both transformations reduce number of branches.  The transformation
is guarded by a target-hook, and is currently enabled only for +R600,
but the correctness has been tested on X86 target using a variety of
CPU benchmarks.

Patch by: Mei Ye

llvm-svn: 187278
2013-07-27 00:01:07 +00:00