Commit Graph

425 Commits

Author SHA1 Message Date
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
Mehdi Amini
c94da20917 Make DataLayout Non-Optional in the Module
Summary:
DataLayout keeps the string used for its creation.

As a side effect it is no longer needed in the Module.
This is "almost" NFC, the string is no longer
canonicalized, you can't rely on two "equals" DataLayout
having the same string returned by getStringRepresentation().

Get rid of DataLayoutPass: the DataLayout is in the Module

The DataLayout is "per-module", let's enforce this by not
duplicating it more than necessary.
One more step toward non-optionality of the DataLayout in the
module.

Make DataLayout Non-Optional in the Module

Module->getDataLayout() will never returns nullptr anymore.

Reviewers: echristo

Subscribers: resistor, llvm-commits, jholewinski

Differential Revision: http://reviews.llvm.org/D7992

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

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@231270 91177308-0d34-0410-b5e6-96231b3b80d8
2015-03-04 18:43:29 +00:00
Sanjoy Das
caee94bbb4 Revert some changes that were made to fix PR20680.
This re-lands change r230921.  r230921 was reverted because it broke a
clang test; a checkin fixing the clang test will be commited shortly.

Summary:
As far as I can tell, the real bug causing the issue was fixed in
r230533.  SCEVExpander should mark an increment operation as nuw or nsw
only if it can *prove* that the operation does not overflow.  There
shouldn't be any situation where we have to do something different
because of no-wrap flags generated by SCEVExpander.

Revert "IndVarSimplify: Allow LFTR to fire more often"

This reverts commit 1ade0f0faa (SVN: 222213).

Revert "IndVarSimplify: Don't let LFTR compare against a poison value"

This reverts commit c0f2b8b528 (SVN: 217102).

Reviewers: majnemer, atrick, spatel

Differential Revision: http://reviews.llvm.org/D7979

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@231018 91177308-0d34-0410-b5e6-96231b3b80d8
2015-03-02 21:41:07 +00:00
NAKAMURA Takumi
6cad61163a Revert r230921, "Revert some changes that were made to fix PR20680.", for now.
It caused a failure on clang/test/Misc/backend-optimization-failure.cpp .

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@230929 91177308-0d34-0410-b5e6-96231b3b80d8
2015-03-02 01:14:03 +00:00
Sanjoy Das
008dd56706 Revert some changes that were made to fix PR20680.
Summary:
As far as I can tell, the real bug causing the issue was fixed in
r230533.  SCEVExpander should mark an increment operation as nuw or nsw
only if it can *prove* that the operation does not overflow.  There
shouldn't be any situation where we have to do something different
because of no-wrap flags generated by SCEVExpander.

Revert "IndVarSimplify: Allow LFTR to fire more often"

This reverts commit 1ade0f0faa (SVN: 222213).

Revert "IndVarSimplify: Don't let LFTR compare against a poison value"

This reverts commit c0f2b8b528 (SVN: 217102).

Reviewers: majnemer, atrick, spatel

Differential Revision: http://reviews.llvm.org/D7979

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@230921 91177308-0d34-0410-b5e6-96231b3b80d8
2015-03-01 23:36:26 +00:00
Chandler Carruth
baceda736e [multiversion] Thread a function argument through all the callers of the
getTTI method used to get an actual TTI object.

No functionality changed. This just threads the argument and ensures
code like the inliner can correctly look up the callee's TTI rather than
using a fixed one.

The next change will use this to implement per-function subtarget usage
by TTI. The changes after that should eliminate the need for FTTI as that
will have become the default.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@227730 91177308-0d34-0410-b5e6-96231b3b80d8
2015-02-01 12:01:35 +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
Chandler Carruth
de5df29556 [PM] Split the LoopInfo object apart from the legacy pass, creating
a LoopInfoWrapperPass to wire the object up to the legacy pass manager.

This switches all the clients of LoopInfo over and paves the way to port
LoopInfo to the new pass manager. No functionality change is intended
with this iteration.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@226373 91177308-0d34-0410-b5e6-96231b3b80d8
2015-01-17 14:16:18 +00:00
Chandler Carruth
eeeec3ce0d [PM] Separate the TargetLibraryInfo object from the immutable pass.
The pass is really just a means of accessing a cached instance of the
TargetLibraryInfo object, and this way we can re-use that object for the
new pass manager as its result.

Lots of delta, but nothing interesting happening here. This is the
common pattern that is developing to allow analyses to live in both the
old and new pass manager -- a wrapper pass in the old pass manager
emulates the separation intrinsic to the new pass manager between the
result and pass for analyses.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@226157 91177308-0d34-0410-b5e6-96231b3b80d8
2015-01-15 10:41:28 +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
David Blaikie
5401ba7099 Update SetVector to rely on the underlying set's insert to return a pair<iterator, bool>
This is to be consistent with StringSet and ultimately with the standard
library's associative container insert function.

This lead to updating SmallSet::insert to return pair<iterator, bool>,
and then to update SmallPtrSet::insert to return pair<iterator, bool>,
and then to update all the existing users of those functions...

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@222334 91177308-0d34-0410-b5e6-96231b3b80d8
2014-11-19 07:49:26 +00:00
David Majnemer
1ade0f0faa IndVarSimplify: Allow LFTR to fire more often
I added a pessimization in r217102 to prevent miscompiles when the
incremented induction variable was used in a comparison; it would be
poison.

Try to use the incremented induction variable more often when we can be
sure that the increment won't end in poison.

Differential Revision: http://reviews.llvm.org/D6222

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@222213 91177308-0d34-0410-b5e6-96231b3b80d8
2014-11-18 02:20:58 +00:00
Jingyue Wu
83c8e732dd Disable indvar widening if arithmetics on the wider type are more expensive
Summary:
Reapply r221772. The old patch breaks the bot because the @indvar_32_bit test
was run whether NVPTX was enabled or not.

IndVarSimplify should not widen an indvar if arithmetics on the wider
indvar are more expensive than those on the narrower indvar. For
instance, although NVPTX64 treats i64 as a legal type, an ADD on i64 is
twice as expensive as that on i32, because the hardware needs to
simulate a 64-bit integer using two 32-bit integers.

Split from D6188, and based on D6195 which adds NVPTXTargetTransformInfo.

Fixes PR21148.

Test Plan:
Added @indvar_32_bit that verifies we do not widen an indvar if the arithmetics
on the wider type are more expensive. This test is run only when NVPTX is
enabled.

Reviewers: jholewinski, eliben, meheff, atrick

Reviewed By: atrick

Subscribers: jholewinski, llvm-commits

Differential Revision: http://reviews.llvm.org/D6196



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@221799 91177308-0d34-0410-b5e6-96231b3b80d8
2014-11-12 18:09:15 +00:00
Jingyue Wu
ee709fe497 Reverts r221772 which fails tests
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@221773 91177308-0d34-0410-b5e6-96231b3b80d8
2014-11-12 07:19:25 +00:00
Jingyue Wu
69adc159ee Disable indvar widening if arithmetics on the wider type are more expensive
Summary:
IndVarSimplify should not widen an indvar if arithmetics on the wider
indvar are more expensive than those on the narrower indvar. For
instance, although NVPTX64 treats i64 as a legal type, an ADD on i64 is
twice as expensive as that on i32, because the hardware needs to
simulate a 64-bit integer using two 32-bit integers.

Split from D6188, and based on D6195 which adds NVPTXTargetTransformInfo.

Fixes PR21148.

Test Plan:
Added @indvar_32_bit that verifies we do not widen an indvar if the arithmetics
on the wider type are more expensive.

Reviewers: jholewinski, eliben, meheff, atrick

Reviewed By: atrick

Subscribers: jholewinski, llvm-commits

Differential Revision: http://reviews.llvm.org/D6196

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@221772 91177308-0d34-0410-b5e6-96231b3b80d8
2014-11-12 06:58:45 +00:00
Zinovy Nis
31713943aa [BUG][INDVAR] Fix for PR21014: wrong SCEV operands commuting for non-commutative instructions
My commit rL216160 introduced a bug PR21014: IndVars widens code 'for (i = ; i < ...; i++) arr[ CONST - i]' into 'for (i = ; i < ...; i++) arr[ i - CONST]'
thus inverting index expression. This patch fixes it. 
Thanks to Jörg Sonnenberger for pointing.

Differential Revision: http://reviews.llvm.org/D5576



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@218867 91177308-0d34-0410-b5e6-96231b3b80d8
2014-10-02 13:01:15 +00:00
Chad Rosier
ecea7ba518 [IndVarSimplify] Widen loop unsigned compares.
This patch extends r217953 to handle unsigned comparison.
Phabricator revision: http://reviews.llvm.org/D5526

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@218659 91177308-0d34-0410-b5e6-96231b3b80d8
2014-09-30 03:17:42 +00:00
Chad Rosier
4150a8de76 [IndVar] Don't widen loop compare unless IV user is sign extended.
PR21030

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@218539 91177308-0d34-0410-b5e6-96231b3b80d8
2014-09-26 20:05:35 +00:00
Chad Rosier
c6b1a7e577 [IndVarSimplify] Partially revert r217953 to see if this fixes the bots.
Specifically, disable widening of unsigned compare instructions.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@217962 91177308-0d34-0410-b5e6-96231b3b80d8
2014-09-17 16:35:09 +00:00
Chad Rosier
c5f6b53403 [IndVarSimplify] Widen loop compare instructions.
This improves other optimizations such as LSR.  A sext may be added to the
compare's other operand, but this can often be hoisted outside of the loop.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@217953 91177308-0d34-0410-b5e6-96231b3b80d8
2014-09-17 14:10:33 +00:00
David Majnemer
e35ac41a3a IndVarSimplify: Address review comments for r217102
No functional change intended, just some cleanups and comments added.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@217115 91177308-0d34-0410-b5e6-96231b3b80d8
2014-09-04 00:23:13 +00:00
David Majnemer
c0f2b8b528 IndVarSimplify: Don't let LFTR compare against a poison value
LinearFunctionTestReplace tries to use the *next* indvar to compare
against when possible.  However, it may be the case that the calculation
for the next indvar has NUW/NSW flags and that it may only be safely
used inside the loop.  Using it in a comparison to calculate the exit
condition could result in observing poison.

This fixes PR20680.

Differential Revision: http://reviews.llvm.org/D5174

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@217102 91177308-0d34-0410-b5e6-96231b3b80d8
2014-09-03 23:03:18 +00:00
Zinovy Nis
63f5912959 [CLNUP] Remove return after llvm_unreachable. Thanks to Hal Finkel for pointing.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@216176 91177308-0d34-0410-b5e6-96231b3b80d8
2014-08-21 13:30:05 +00:00
Zinovy Nis
164cd0161e [INDVARS] Extend using of widening of induction variables for the cases of "sub nsw" and "mul nsw" instructions.
Currently only "add nsw" are widened. This patch eliminates tons of "sext" instructions for 64 bit code (and the corresponding target code) in cases like:

int N = 100;
float **A;

void foo(int x0, int x1)
{
        float * A_cur = &A[0][0];
        float * A_next = &A[1][0];
        for(int x = x0; x < x1; ++x).
        {
          // Currently only [x+N] case is widened. Others 2 cases lead to sext.
          // This patch fixes it, so all 3 cases do not need sext.
          const float div = A_cur[x + N] + A_cur[x - N] + A_cur[x * N];
          A_next[x] = div;
        }
}
...
> clang++ test.cpp -march=core-avx2 -Ofast  -fno-unroll-loops -fno-tree-vectorize -S -o -

Differential Revision: http://reviews.llvm.org/D4695



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@216160 91177308-0d34-0410-b5e6-96231b3b80d8
2014-08-21 08:25:45 +00:00
Craig Topper
431bdfc4c1 Repace SmallPtrSet with SmallPtrSetImpl in function arguments to avoid needing to mention the size.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@216158 91177308-0d34-0410-b5e6-96231b3b80d8
2014-08-21 05:55:13 +00:00
Craig Topper
db77b82ed5 Revert "Repace SmallPtrSet with SmallPtrSetImpl in function arguments to avoid needing to mention the size."
Getting a weird buildbot failure that I need to investigate.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@215870 91177308-0d34-0410-b5e6-96231b3b80d8
2014-08-18 00:24:38 +00:00
Craig Topper
f06c7072c2 Repace SmallPtrSet with SmallPtrSetImpl in function arguments to avoid needing to mention the size.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@215868 91177308-0d34-0410-b5e6-96231b3b80d8
2014-08-17 23:47:00 +00:00
Craig Topper
8d7221ccf5 [C++] Use 'nullptr'. Transforms edition.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@207196 91177308-0d34-0410-b5e6-96231b3b80d8
2014-04-25 05:29:35 +00:00
Chandler Carruth
7962dbdc65 [Modules] Fix potential ODR violations by sinking the DEBUG_TYPE
definition below all of the header #include lines, lib/Transforms/...
edition.

This one is tricky for two reasons. We again have a couple of passes
that define something else before the includes as well. I've sunk their
name macros with the DEBUG_TYPE.

Also, InstCombine contains headers that need DEBUG_TYPE, so now those
headers #define and #undef DEBUG_TYPE around their code, leaving them
well formed modular headers. Fixing these headers was a large motivation
for all of these changes, as "leaky" macros of this form are hard on the
modules implementation.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@206844 91177308-0d34-0410-b5e6-96231b3b80d8
2014-04-22 02:55:47 +00:00
Chandler Carruth
36b699f2b1 [C++11] Add range based accessors for the Use-Def chain of a Value.
This requires a number of steps.
1) Move value_use_iterator into the Value class as an implementation
   detail
2) Change it to actually be a *Use* iterator rather than a *User*
   iterator.
3) Add an adaptor which is a User iterator that always looks through the
   Use to the User.
4) Wrap these in Value::use_iterator and Value::user_iterator typedefs.
5) Add the range adaptors as Value::uses() and Value::users().
6) Update *all* of the callers to correctly distinguish between whether
   they wanted a use_iterator (and to explicitly dig out the User when
   needed), or a user_iterator which makes the Use itself totally
   opaque.

Because #6 requires churning essentially everything that walked the
Use-Def chains, I went ahead and added all of the range adaptors and
switched them to range-based loops where appropriate. Also because the
renaming requires at least churning every line of code, it didn't make
any sense to split these up into multiple commits -- all of which would
touch all of the same lies of code.

The result is still not quite optimal. The Value::use_iterator is a nice
regular iterator, but Value::user_iterator is an iterator over User*s
rather than over the User objects themselves. As a consequence, it fits
a bit awkwardly into the range-based world and it has the weird
extra-dereferencing 'operator->' that so many of our iterators have.
I think this could be fixed by providing something which transforms
a range of T&s into a range of T*s, but that *can* be separated into
another patch, and it isn't yet 100% clear whether this is the right
move.

However, this change gets us most of the benefit and cleans up
a substantial amount of code around Use and User. =]

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@203364 91177308-0d34-0410-b5e6-96231b3b80d8
2014-03-09 03:16:01 +00:00
Craig Topper
7b62be28cb [C++11] Add 'override' keyword to virtual methods that override their base class.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@202953 91177308-0d34-0410-b5e6-96231b3b80d8
2014-03-05 09:10:37 +00:00
Chandler Carruth
03e36d752c [Modules] Move CFG.h to the IR library as it defines graph traits over
IR types.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@202827 91177308-0d34-0410-b5e6-96231b3b80d8
2014-03-04 11:45:46 +00:00
Rafael Espindola
57edc9d4ff Make DataLayout a plain object, not a pass.
Instead, have a DataLayoutPass that holds one. This will allow parts of LLVM
don't don't handle passes to also use DataLayout.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@202168 91177308-0d34-0410-b5e6-96231b3b80d8
2014-02-25 17:30:31 +00:00
Rafael Espindola
ec89b9fb9e Make some DataLayout pointers const.
No functionality change. Just reduces the noise of an upcoming patch.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@202087 91177308-0d34-0410-b5e6-96231b3b80d8
2014-02-24 23:12:18 +00:00
Rafael Espindola
f116e5308d Rename many DataLayout variables from TD to DL.
I am really sorry for the noise, but the current state where some parts of the
code use TD (from the old name: TargetData) and other parts use DL makes it
hard to write a patch that changes where those variables come from and how
they are passed along.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@201827 91177308-0d34-0410-b5e6-96231b3b80d8
2014-02-21 00:06:31 +00:00
Paul Robinson
2684ddd72e Disable most IR-level transform passes on functions marked 'optnone'.
Ideally only those transform passes that run at -O0 remain enabled,
in reality we get as close as we reasonably can.
Passes are responsible for disabling themselves, it's not the job of
the pass manager to do it for them.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@200892 91177308-0d34-0410-b5e6-96231b3b80d8
2014-02-06 00:07:05 +00:00
Chandler Carruth
6a67a3f3ec [LPM] Fix PR18642, a pretty nasty bug in IndVars that "never mattered"
because of the inside-out run of LoopSimplify in the LoopPassManager and
the fact that LoopSimplify couldn't be "preserved" across two
independent LoopPassManagers.

Anyways, in that case, IndVars wasn't correctly preserving an LCSSA PHI
node because it thought it was rewriting (via SCEV) the incoming value
to a loop invariant value. While it may well be invariant for the
current loop, it may be rewritten in terms of an enclosing loop's
values. This in and of itself is fine, as the LCSSA PHI node in the
enclosing loop for the inner loop value we're rewriting will have its
own LCSSA PHI node if used outside of the enclosing loop. With me so
far?

Well, the current loop and the enclosing loop may share an exiting
block and exit block, and when they do they also share LCSSA PHI nodes.
In this case, its not valid to RAUW through the LCSSA PHI node.

Expected crazy test included.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@200372 91177308-0d34-0410-b5e6-96231b3b80d8
2014-01-29 04:40:19 +00:00
Chandler Carruth
7f2eff792a [PM] Split DominatorTree into a concrete analysis result object which
can be used by both the new pass manager and the old.

This removes it from any of the virtual mess of the pass interfaces and
lets it derive cleanly from the DominatorTreeBase<> template. In turn,
tons of boilerplate interface can be nuked and it turns into a very
straightforward extension of the base DominatorTree interface.

The old analysis pass is now a simple wrapper. The names and style of
this split should match the split between CallGraph and
CallGraphWrapperPass. All of the users of DominatorTree have been
updated to match using many of the same tricks as with CallGraph. The
goal is that the common type remains the resulting DominatorTree rather
than the pass. This will make subsequent work toward the new pass
manager significantly easier.

Also in numerous places things became cleaner because I switched from
re-running the pass (!!! mid way through some other passes run!!!) to
directly recomputing the domtree.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@199104 91177308-0d34-0410-b5e6-96231b3b80d8
2014-01-13 13:07:17 +00:00
Chandler Carruth
56e1394c88 [cleanup] Move the Dominators.h and Verifier.h headers into the IR
directory. These passes are already defined in the IR library, and it
doesn't make any sense to have the headers in Analysis.

Long term, I think there is going to be a much better way to divide
these matters. The dominators code should be fully separated into the
abstract graph algorithm and have that put in Support where it becomes
obvious that evn Clang's CFGBlock's can use it. Then the verifier can
manually construct dominance information from the Support-driven
interface while the Analysis library can provide a pass which both
caches, reconstructs, and supports a nice update API.

But those are very long term, and so I don't want to leave the really
confusing structure until that day arrives.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@199082 91177308-0d34-0410-b5e6-96231b3b80d8
2014-01-13 09:26:24 +00:00
Andrew Trick
b4e0c9b85d Reapply r198654 "indvars: sink truncates outside the loop."
This doesn't seem to have actually broken anything. It was paranoia
on my part. Trying again now that bots are more stable.

This is a follow up of the r198338 commit that added truncates for
lcssa phi nodes. Sinking the truncates below the phis cleans up the
loop and simplifies subsequent analysis within the indvars pass.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@198678 91177308-0d34-0410-b5e6-96231b3b80d8
2014-01-07 06:59:12 +00:00
Andrew Trick
2352abb7c6 Revert "indvars: sink truncates outside the loop."
This reverts commit r198654.

One of the bots reported a SciMark failure.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@198659 91177308-0d34-0410-b5e6-96231b3b80d8
2014-01-07 01:50:58 +00:00
Andrew Trick
ced88c5918 indvars: sink truncates outside the loop.
This is a follow up of the r198338 commit that added truncates for
lcssa phi nodes. Sinking the truncates below the phis cleans up the
loop and simplifies subsequent analysis within the indvars pass.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@198654 91177308-0d34-0410-b5e6-96231b3b80d8
2014-01-07 01:02:55 +00:00
Andrew Trick
f86063e7ec 80 col. comment.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@198653 91177308-0d34-0410-b5e6-96231b3b80d8
2014-01-07 01:02:52 +00:00
Andrew Trick
5f8e79e6d2 indvars: cleanup the IV visitor. It does more than gather sext/zext info.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@198353 91177308-0d34-0410-b5e6-96231b3b80d8
2014-01-02 21:12:11 +00:00
Andrew Trick
fcbe3d9501 indvars: insert truncate at loop boundary to avoid redundant IVs.
When widening an IV to remove s/zext, we generally try to eliminate
the original narrow IV. However, LCSSA phi nodes outside the loop were
still using the original IV. Clean this up more aggressively to avoid
redundancy in generated code.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@198338 91177308-0d34-0410-b5e6-96231b3b80d8
2014-01-02 19:29:38 +00:00
Andrew Trick
c7b0b7dc8f Add support to indvars for optimizing sadd.with.overflow.
Split sadd.with.overflow into add + sadd.with.overflow to allow
analysis and optimization. This should ideally be done after
InstCombine, which can perform code motion (eventually indvars should
run after all canonical instcombines). We want ISEL to recombine the
add and the check, at least on x86.

This is currently under an option for reducing live induction
variables: -liv-reduce. The next step is reducing liveness of IVs that
are live out of the overflow check paths. Once the related
optimizations are fully developed, reviewed and tested, I do expect
this to become default.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@197926 91177308-0d34-0410-b5e6-96231b3b80d8
2013-12-23 23:31:49 +00:00
Andrew Trick
4d4bbaf997 Fix SCEVExpander: don't try to expand quadratic recurrences outside a loop.
Partial fix for PR17459: wrong code at -O3 on x86_64-linux-gnu
(affecting trunk and 3.3)

When SCEV expands a recurrence outside of a loop it attempts to scale
by the stride of the recurrence. Chained recurrences don't work that
way. We could compute binomial coefficients, but would hve to
guarantee that the chained AddRec's are in a perfectly reduced form.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@193438 91177308-0d34-0410-b5e6-96231b3b80d8
2013-10-25 21:35:56 +00:00
Juergen Ributzka
d084153a8f Fix a bug in LinearFunctionTestReplace that created invalid loop exit checks.
Reviewed by Andy

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@193303 91177308-0d34-0410-b5e6-96231b3b80d8
2013-10-24 05:29:56 +00:00
Andrew Trick
577ac566c4 Clarify comments in genLoopLimit.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@193292 91177308-0d34-0410-b5e6-96231b3b80d8
2013-10-24 00:43:38 +00:00
Matt Arsenault
14807bd8c8 Teach ScalarEvolution about pointer address spaces
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@190425 91177308-0d34-0410-b5e6-96231b3b80d8
2013-09-10 19:55:24 +00:00