Commit Graph

483 Commits

Author SHA1 Message Date
Arthur Eubanks cabe1b1124 [polly][NewPM][test] Fix polly tests under -enable-new-pm
In preparation for turning on opt's -enable-new-pm by default, this pins
uses of passes via the legacy "opt -passname" with pass names beginning
with "polly-" and "polyhedral-info" to the legacy PM. Many of these
tests use -analyze, which isn't supported in the new PM.

(This doesn't affect uses of "opt -passes=passname").

rL240766 accidentally removed `-polly-prepare` in
phi_not_grouped_at_top.ll, and it also doesn't use the output of
-analyze.

Reviewed By: Meinersbur

Differential Revision: https://reviews.llvm.org/D94266
2021-01-19 12:38:58 -08:00
Michael Kruse e408935bb5 [Polly][ScopBuilder] Use only modeled instructions to compute statement granularity.
ScopBuilder distributes independent instructions between statements.
Only modeled (e.g. not synthesizable) instructions are represented.
To compute independence, non-modeled instructions were used in some
parts of determining instruction independence, which could lead to the
re-introduction of non-model instructions.

In particular, required invariant loads could be added to instruction
list, which then led to redundant MemoryAccesses for such a load.

This fixes llvm.org/PR48059.
2020-11-10 15:30:16 -06:00
Roman Lebedev b4916918e5
[SCEV] SCEVPtrToIntExpr simplifications
If we've got an SCEVPtrToIntExpr(op), where op is not an SCEVUnknown,
we want to sink the SCEVPtrToIntExpr into an operand,
so that the operation is performed on integers,
and eventually we end up with just an `SCEVPtrToIntExpr(SCEVUnknown)`.

Reviewed By: mkazantsev

Differential Revision: https://reviews.llvm.org/D89692
2020-10-30 11:13:35 +03:00
Roman Lebedev 81fc53a36a
[SCEV] Introduce SCEVPtrToIntExpr (PR46786)
And use it to model LLVM IR's `ptrtoint` cast.

This is essentially an alternative to D88806, but with no chance for
all the problems it caused due to having the cast as implicit there.
(see rG7ee6c402474a2f5fd21c403e7529f97f6362fdb3)

As we've established by now, there are at least two reasons why we want this:
* It will allow SCEV to actually model the `ptrtoint` casts
  and their operands, instead of treating them as `SCEVUnknown`
* It should help with initial problem of PR46786 - this should eventually allow us
  to not loose pointer-ness of an expression in more cases

As discussed in [[ https://bugs.llvm.org/show_bug.cgi?id=46786 | PR46786 ]], in principle,
we could just extend `SCEVUnknown` with a `is ptrtoint` cast, because `ScalarEvolution::getPtrToIntExpr()`
should sink the cast as far down into the expression as possible,
so in the end we should always end up with `SCEVPtrToIntExpr` of `SCEVUnknown`.

But i think that it isn't the best solution, because it doesn't really matter
from memory consumption side - there probably won't be *that* many `SCEVPtrToIntExpr`s
for it to matter, and it allows for much better discoverability.

Reviewed By: mkazantsev

Differential Revision: https://reviews.llvm.org/D89456
2020-10-30 11:13:35 +03:00
Wei Wang 46ebb619bf [FIX] Resolve test failure in polly/test/ScopInfo/memcpy-raw-source.ll
scoped-noalias -> scoped-noalias-aa

reference: https://reviews.llvm.org/D84542

Reviewed By: aeubanks

Differential Revision: https://reviews.llvm.org/D84720
2020-07-28 09:15:40 -07:00
Roman Lebedev a2619a60e4
Reland "[ScalarEvolution] createSCEV(): recognize `udiv`/`urem` disguised as an `sdiv`/`srem`"
This reverts commit d3e3f36ff1,
which reverter the original commit 2c16100e6f,
but with polly tests now actually passing.
2020-07-06 18:00:22 +03:00
Arthur Eubanks b210c9899b [BasicAA] Replace -basicaa with -basic-aa in polly
Follow up to https://reviews.llvm.org/D82607.
2020-06-30 15:50:17 -07:00
Simon Pilgrim 74dc081ef2 Update polly tests to use -disable-basicaa to -disable-basic-aa
These were missed in rG4cd19a6e15120cb
2020-06-27 15:56:01 +01:00
Eli Friedman f26bdb539e Make Value::getPointerAlignment() return an Align, not a MaybeAlign.
If we don't know anything about the alignment of a pointer, Align(1) is
still correct: all pointers are at least 1-byte aligned.

Included in this patch is a bugfix for an issue discovered during this
cleanup: pointers with "dereferenceable" attributes/metadata were
assumed to be aligned according to the type of the pointer.  This
wasn't intentional, as far as I can tell, so Loads.cpp was fixed to
stop making this assumption. Frontends may need to be updated.  I
updated clang's handling of C++ references, and added a release note for
this.

Differential Revision: https://reviews.llvm.org/D80072
2020-05-20 16:37:20 -07:00
Eli Friedman 1a6e4a2cf6 Fix polly tests after D79968. 2020-05-15 15:15:09 -07:00
Eli Friedman 4532a50899 Infer alignment of unmarked loads in IR/bitcode parsing.
For IR generated by a compiler, this is really simple: you just take the
datalayout from the beginning of the file, and apply it to all the IR
later in the file. For optimization testcases that don't care about the
datalayout, this is also really simple: we just use the default
datalayout.

The complexity here comes from the fact that some LLVM tools allow
overriding the datalayout: some tools have an explicit flag for this,
some tools will infer a datalayout based on the code generation target.
Supporting this properly required plumbing through a bunch of new
machinery: we want to allow overriding the datalayout after the
datalayout is parsed from the file, but before we use any information
from it. Therefore, IR/bitcode parsing now has a callback to allow tools
to compute the datalayout at the appropriate time.

Not sure if I covered all the LLVM tools that want to use the callback.
(clang? lli? Misc IR manipulation tools like llvm-link?). But this is at
least enough for all the LLVM regression tests, and IR without a
datalayout is not something frontends should generate.

This change had some sort of weird effects for certain CodeGen
regression tests: if the datalayout is overridden with a datalayout with
a different program or stack address space, we now parse IR based on the
overridden datalayout, instead of the one written in the file (or the
default one, if none is specified). This broke a few AVR tests, and one
AMDGPU test.

Outside the CodeGen tests I mentioned, the test changes are all just
fixing CHECK lines and moving around datalayout lines in weird places.

Differential Revision: https://reviews.llvm.org/D78403
2020-05-14 13:03:50 -07:00
Michael Kruse e8227804ac [Polly] Update ISL to isl-0.22.1-87-gfee05a13.
The primary motivation is to fix an assertion failure in
isl_basic_map_alloc_equality:

    isl_assert(ctx, room_for_con(bmap, 1), return -1);

Although the assertion does not occur anymore, I could not identify
which of ISL's commits fixed it.

Compared to the previous ISL version, Polly requires some changes for this update

 * Since ISL commit
   20d3574 "perform parameter alignment by modifying both arguments to function"
   isl_*_gist_* and similar functions do not always align the paramter
   list anymore. This caused the parameter lists in JScop files to
   become out-of-sync. Since many regression tests use JScop files with
   a fixed parameter list and order, we explicitly call align_params to
   ensure a predictable parameter list.

 * ISL changed some return types to isl_size, a typedef of (signed) int.
   This caused some issues where the return type was unsigned int before:
   - No overload for std::max(unsigned,isl_size)
   - It cause additional 'mixed signed/unsigned comparison' warnings.
     Since they do not break compilation, and sizes larger than 2^31
     were never supported, I am going to fix it separately.

 * With the change to isl_size, commit
   57d547 "isl_*_list_size: return isl_size"
   also changed the return value in case of an error from 0 to -1. This
   caused undefined looping over isl_iterator since the 'end iterator'
   got index -1, never reached from the 'begin iterator' with index 0.

 * Some internal changes in ISL caused the number of operations to
   increase when determining access ranges to determine aliasing
   overlaps. In one test, this caused exceeding the default limit of
   800000. The operations-limit was disabled for this test.
2020-02-10 19:03:08 -06:00
Eli Friedman 2f6b9edfa8 [AliasAnalysis] Add missing FMRB_* enums.
Previously, the enums didn't account for all the possible cases, which
could cause misleading results (particularly for a "switch" on
FunctionModRefBehavior).

Fixes regression in polly from recent patch to add writeonly to memset.

While I'm here, also fix a few dubious uses of the FMRB_* enum values.

Differential Revision: https://reviews.llvm.org/D73154
2020-01-28 15:47:08 -08:00
Eli Friedman d9e6196312 [polly] XFAIL memset_null.ll.
I'm working on a patch, but not sure how long it'll take.
2020-01-21 17:29:44 -08:00
Fangrui Song a36ddf0aa9 Migrate function attribute "no-frame-pointer-elim"="false" to "frame-pointer"="none" as cleanups after D56351 2019-12-24 16:27:51 -08:00
Fangrui Song 502a77f125 Migrate function attribute "no-frame-pointer-elim" to "frame-pointer"="all" as cleanups after D56351 2019-12-24 15:57:33 -08:00
Michael Kruse d72637f5cc [ScopBuilder] Fix bug 38358 by preserving correct order of ScopStmts.
ScopBuilder::buildEqivClassBlockStmts creates ScopStmts for instruction
groups in basic block and inserts these ScopStmts into Scop::StmtMap,
however, as described in llvm.org/PR38358, comment #5, StmtScops are
inserted into vector ScopStmt[BB] in wrong order.  As a result,
ScopBuilder::buildSchedule creates wrong order sequence node.

Looking closer to code, it's clear there is no equivalent classes with
interleaving isOrderedInstruction(memory access) instructions after
joinOrderedInstructions.  Afterwards, ScopStmts need to be created and
inserted in the original order of memory access instructions, however,
at the moment ScopStmts are inserted in the order of leader instructions
which are probably not memory access instructions.

The fix is simple with a standalone loop scanning
isOrderedInstruction(memory access) instructions in basic block and
inserting elements into LeaderToInstList one by one.  The patch also
removes double reversing operations which are now unnecessary.

New test preserve-equiv-class-order-in-basic_block.ll is also added.

Differential Revision: https://reviews.llvm.org/D68941

llvm-svn: 375192
2019-10-17 23:55:35 +00:00
Michael Kruse 87baae85cd [ScopBuilder] Skip getting leader when merging statements to close holes.
Function joinOrderedInstructions merges instructions when a leader is encountered twice.
It also notices that leaders in SeenLeaders may lose their leadership in previous merging,
and tries to handle the case using following code:

    Instruction *PrevLeader = UnionFind.getLeaderValue(SeenLeaders.back());

However, this is wrong because it always gets leader for the last element of SeenLeaders,
and I believe it's wrong even we get leader for Prev here.  As a result, Statements in cases
like the one in patch aren't merged as expected.  After investigation, I believe it's
unnecessary to get leader instruction at all.  This is based on fact: Although leaders in
SeenLeaders could lose leadership, they only lose to others in SeenLeaders, in other words,
one existing leader will be chosen as new leader of merged equivalent statements.  We can
take advantage of this and simply check if current leader equals to Prev and break merging
if it does.

The patch also adds a new test.

Patch by bin.narwal <bin.narwal@gmail.com>

Differential Revision: https://reviews.llvm.org/D67007

llvm-svn: 371801
2019-09-13 01:04:38 +00:00
Eli Friedman 9b234b388d [Polly] Don't crash on invalid delinearization result.
In certain cases, it's possible for delinearization to decide one of the
array dimensions should be some function of an induction variable inside
the scop.  Make sure if this happens, we refuse to use those dimensions
for delinearization.

Usually, we end up rejecting the scop before it actually crashes, but it
looks like it's possible to slip past other checks in certain cases
involving smax expressions.

Fixes a crash that started showing up this week on the polly AOSP
builder.  As far as I can tell, this is a longstanding issue, though;
it was just exposed by better SCEV analysis of smin expressions.

Differential Revision: https://reviews.llvm.org/D61807

llvm-svn: 360708
2019-05-14 21:32:54 +00:00
Michael Kruse 2698390c68 [ZoneAlgo] Fix PHI inconsistency in invalid contexts.
PHI nodes (reads) could point to multiple instances of predecessor
blocks (PHI writes) when in an invalid context. Fix by removing PHI
instances that are in an invalid or ouside assumed context.

This fixes llvm.org/PR41656.

llvm-svn: 360454
2019-05-10 18:38:13 +00:00
Keno Fischer aa1b6f1cfb [polly][SCEV] Expand SCEV matcher cases for new smin/umin ops
These were added in rL360159, but I neglected to update polly at the
same time.

llvm-svn: 360238
2019-05-08 10:36:04 +00:00
James Y Knight 693d39dd12 Remove irrelevant references to legacy git repositories from
compiler identification lines in test-cases.

(Doing so only because it's then easier to search for references which
are actually important and need fixing.)

llvm-svn: 351200
2019-01-15 16:18:52 +00:00
Michael Kruse 842bdd0071 [ScopBuilder] Set domain to empty instead of NULL.
The domain generation used nullptr to mark the domain of an error block
as never-executed. Later, nullptr domains are recreated with a
zero-tuple domain that then mismatches with the expected domain the
error block within the loop.

Instead of using nullptr, assign an empty domain which preserves the
expected space. Remove empty domains during SCoP simplification.

Fixes llvm.org/PR38218.

llvm-svn: 338646
2018-08-01 22:28:32 +00:00
Tobias Grosser 17a098dedf test: use regex matchers to make test-case robust against register renumberings
Suggested-by: Michael Kruse
llvm-svn: 335813
2018-06-28 07:11:48 +00:00
Tobias Grosser a78a809afc Adjust to recent LLVM changes to fix buildbots
llvm-svn: 334893
2018-06-16 17:38:19 +00:00
Tobias Grosser ee5762cfab [test] Fix a typo in a test case [NFCI]
Also remove an undef value that does not add any value to the test case.

llvm-svn: 334661
2018-06-13 21:46:29 +00:00
Eli Friedman 9ae56b9a0e [SCEVAffinator] Fix handling of pwaff complexity limit.
nullptr is not a valid affine expression, and none of the callers check
for null, so we eventually hit an isl error and crash.

Instead, invalidate the scop and return a constant zero.

Differential Revision: https://reviews.llvm.org/D46445

llvm-svn: 332309
2018-05-14 23:05:43 +00:00
Tobias Grosser 6bbca36414 Adjust to debug info metadata format change.
Rename variable to retainedNodes. This unbreaks the Polly builds.

llvm-svn: 331960
2018-05-10 07:09:10 +00:00
Michael Kruse e330071b43 [ScopInfo] Remove bail out condition in buildMinMaxAccess().
The condition was introduced in r267142 to mitigate a long compile-time
case. In r306087, a max-computation limit was introduced that should
handle the same case while leaving the max disjuncts heuristic it
should have replaced intact.

Today, the max disjuncts bail-out causes problems in that it prematurely
stops SCoPs from being detected, e.g. in SPEC's lbm. This would hit less
like if isl_set_coalesce would be called after isl_set_remove_divs
(which makes more basic_set likely to be coalescable) instead of before.

This patch tries to remove the premature max-disjuncts bail-out
condition by using simple_hull() to reduce the computational overhead,
instead of directly invalidating that SCoP.

Differential Revision: https://reviews.llvm.org/D45066

Contributed-by: Sahil Girish Yerawar <cs15btech11044@iith.ac.in>
llvm-svn: 331891
2018-05-09 16:23:56 +00:00
Tobias Grosser 1c88d41020 [test] Replace undef with true/false to make test case less fragile
This test case does not require undef to be present in branch
conditions. Replace these undef values with true/false values to clarify
the control-flow required to reach the loop under testing.

llvm-svn: 331744
2018-05-08 07:24:05 +00:00
Michael Kruse beffdb9daa [ScopDetect] Reject loop with multiple exit blocks.
The current statement domain derivation algorithm does not (always)
consider that different exit blocks of a loop can have different
conditions to be reached.

From the code

      for (int i = n; ; i-=2) {
        if (i <= 0) goto even;
        if (i <= 1) goto odd;
        A[i] = i;
      }
    even:
      A[0] = 42;
      return;
    odd:
      A[1] = 21;
      return;

Polly currently derives the following domains:

        Stmt_even_critedge
            Domain :=
                [n] -> { Stmt_even_critedge[] };
        Stmt_odd
            Domain :=
                [n] -> { Stmt_odd[] : (1 + n) mod 2 = 0 and n > 0 };

while the domain for the odd case is correct, Stmt_even is assumed to be
executed unconditionally, which is obviously wrong. While projecting out
the loop dimension in `adjustDomainDimensions`, it does not consider
that there are other exit condition that have matched before.

I don't know a how to fix this without changing a lot of code. Therefore
This patch rejects loops with multiple exist blocks to fix the
miscompile of test-suite's uuencode.

The odd condition is transformed by LLVM to

    %cmp1 = icmp eq i64 %indvars.iv, 1

such that the project_out in adjustDomainDimensions() indeed only
matches for odd n (using this condition only, we'd have an infinite loop
otherwise).

The even condition manifests as

    %cmp = icmp slt i64 %indvars.iv, 3

Because buildDomainsWithBranchConstraints() does not consider other exit
conditions, it has to assume that the induction variable will eventually
be lower than 3 and taking this exit.

IMHO we need to reuse the algorithm that determines the number of
iterations (addLoopBoundsToHeaderDomain) to determine which exit
condition applies first. It has to happen in
buildDomainsWithBranchConstraints() because the result will need to
propagate to successor BBs. Currently addLoopBoundsToHeaderDomain() just
look for union of all backedge conditions (which means leaving not the
loop here). The patch in llvm.org/PR35465 changes it to look for exit
conditions instead. This is required because there might be other exit
conditions that do not alternatively go back to the loop header.

Differential Revision: https://reviews.llvm.org/D45649

llvm-svn: 330858
2018-04-25 18:53:33 +00:00
Michael Kruse 5369ea5dd5 Allow arbitrary function calls for debugging purposes.
Add the switch -polly-debug-func to define the name of a debug
function. This function is ignored for any validity check.

Its purpose is to allow to observe a value after transformation by a
SCoP, and to follow which statements are executed in which order. For
instance, consider the following code:

    static void dbg_printf(int sum, int i) {
      fprintf(stderr, "The value of sum is %d, i=%d\n", sum, i);
      fflush(stderr);
    }

    void func(int n) {
      int sum = 0;
      for (int i = 0; i < 16; i+=1) {
        sum += i;
        dbg_printf(sum, i);
      }
    }

Executing this after Polly's codegen with -polly-debug-func=dbg_printf
reveals the new execution order and the assumed values at that point of
execution.

Differential Revision: https://reviews.llvm.org/D45728

llvm-svn: 330466
2018-04-20 18:55:44 +00:00
Michael Kruse db6f71e48d [ScopInfo] Avoid iterator invalidation.
Commit r329640 introduced the removal of all MemoryAccesses of a Scop.
It accidentally continued iterating over a vector whose iterators
have been invalidated by a MemoryAccess removal.

Make a copy of the MemoryAccesses to remove to iterate over while
removing them.

llvm-svn: 329653
2018-04-10 01:20:41 +00:00
Michael Kruse 192e7f72ca [ScopInfo] Completely remove MemoryAccesses when their parent statement is removed.
Removing a statement left its MemoryAccesses in some lists and maps of
the SCoP.  Which lists depends on at which phase of the SCoP
construction the statement is deleted.  Follow-up passes could still see
the already deleted MemoryAccesses by iterating through these
lists/maps, resulting in an access violation.

When removing a ScopStmt, also remove all its MemoryAccesses by using
the same mechnism that removes a MemoryAccess.

llvm-svn: 329640
2018-04-09 23:13:05 +00:00
Michael Kruse df8e140349 Remove immediate dominator heuristic for error block detection.
This patch removes the heuristic in
- Polly :: lib/Support/ScopHelper.cpp

The heuristic forces blocks that directly follow a loop header to not to be considered error blocks.
It was introduced in r249611 with the following commit message:

>   This replaces the support for user defined error functions by a
>   heuristic that tries to determine if a call to a non-pure function
>   should be considered "an error". If so the block is assumed not to be
>   executed at runtime. While treating all non-pure function calls as
>   errors will allow a lot more regions to be analyzed, it will also
>   cause us to dismiss a lot again due to an infeasible runtime context.
>   This patch tries to limit that effect. A non-pure function call is
>   considered an error if it is executed only in conditionally with
>   regards to a cheap but simple heuristic.

In the code below `CCK_Abort2()` would be considered as an error block, but not `CCK_Abort1()` due to this heuristic.
```
for (int i = 0; i < n; i+=1) {
  if (ErrorCondition1)
    CCK_Abort1(); // No __attribute__((noreturn))
  if (ErrorCondition2)
    CCK_Abort2(); // No __attribute__((noreturn))
}
```

This does not seem useful. Checking error conditions in the beginning of some work is quite common. It causes a switch default-case to be not considered an error block in SPEC's cactuBSSN. The comment justifying the heuristic mentions a "load", which does not seem to be applicable here. It has been proposed to remove the heuristic.

In addition, the patch fixes the following test cases:
- Polly :: ScopDetect/mod_ref_read_pointer.ll
- Polly :: ScopInfo/max-loop-depth.ll
- Polly :: ScopInfo/mod_ref_access_pointee_arguments.ll
- Polly :: ScopInfo/mod_ref_read_pointee_arguments.ll
- Polly :: ScopInfo/mod_ref_read_pointer.ll
- Polly :: ScopInfo/mod_ref_read_pointers.ll

The test cases failed after removing the heuristic.

Differential Revision: https://reviews.llvm.org/D45274

Contributed-by: Lorenzo Chelini <l.chelini@icloud.com>
llvm-svn: 329548
2018-04-09 06:07:44 +00:00
Tobias Grosser e5340a8ce9 Move code generation test case to test/CodeGen/
llvm-svn: 327857
2018-03-19 15:05:30 +00:00
Tobias Grosser b94863001a [ScopInfo] Do not use the set dimension ids to carry loop information
isl does not guarantee that set dimension ids will be preserved, so using them
to carry information is not a good idea. Furthermore, the loop information can
be derived without problem from the statement itself. As this even requires
less code than propagating loop information on set dimension ids, starting from
this commit we just derive the loop information in collectSurroundingLoops
directly from the IR.

Interestingly this also results in a couple of isl sets to take a simpler
representation.

llvm-svn: 326664
2018-03-03 19:27:54 +00:00
Tobias Grosser fa8079d0dc Update isl to isl-0.18-1047-g4a20ef8
This update:

  - Removes several deprecated functions (e.g., isl_band).
  - Improves the pretty-printing of sets by detecting modulos and "false"
    equalities.
  - Minor improvements to coalescing and increased robustness of the isl
    scheduler.

This update does not yet include isl commit isl-0.18-90-gd00cb45
(isl_pw_*_alloc: add missing check for compatible spaces, Wed Sep 6 12:18:04
2017 +0200), as this additional check is too tight and unfortunately causes
two test case failures in Polly. A patch has been submitted to isl and will be
included in the next isl update for Polly.

llvm-svn: 325557
2018-02-20 07:26:42 +00:00
Michael Kruse a6716d9d81 [ScopBuilder] scalar-indep: Fix mutually referencing PHIs.
Two or more PHIs mutually using each other directly or indirectly as
incoming value could cause that a PHI WRITE be added before the PHI READ
(i.e. it overwrites the current incoming value with the next incoming
value before it being read).

Fix by ensuring that the PHI WRITE and PHI READ are in the same statement.

This should fix the miscompile of SingleSource/Benchmark/Misc/whetstone
from the test-suite.

llvm-svn: 324934
2018-02-12 21:09:40 +00:00
Michael Kruse a43ba2d84f [ScopBuilder] Make -polly-stmt-granularity=scalar-indep the default.
Splitting basic blocks into multiple statements if there are now
additional scalar dependencies gives more freedom to the scheduler, but
more statements also means higher compile-time complexity. Switch to
finer statement granularity, the additional compile time should be
limited by the number of operations quota.

The regression tests are written for the -polly-stmt-granularity=bb
setting, therefore we add that flag to those tests that break with the
new default. Some of the tests only fail because the statements are
named differently due to a basic block resulting in multiple statements,
but which are removed during simplification of statements without
side-effects. Previous commits tried to reduce this effect, but it is
not completely avoidable.

Differential Revision: https://reviews.llvm.org/D42151

llvm-svn: 324169
2018-02-03 06:59:47 +00:00
Michael Kruse a230f22f4b [ScopBuilder] Prefer PHI Write accesses in the statement the incoming value is defined.
Theoretically, a PHI write can be added to any statement that represents
the incoming basic block. We previously always chose the last because
the incoming value's definition is guaranteed to be defined.

With this patch the PHI write is added to the statement that defines the
incoming value. It avoids the requirement for a scalar dependency between
the defining statement and the statement containing the write. As such the
logic for -polly-stmt-granularity=scalar-indep that ensures that there is
such scalar dependencies can be removed.

Differential Revision: https://reviews.llvm.org/D42147

llvm-svn: 323284
2018-01-23 23:56:36 +00:00
Daniel Neilson 751a2cebc5 Change memcpy/memove/memset to have dest and source alignment attributes (Step 1).
Summary:
 Upstream LLVM is changing the the prototypes of the @llvm.memcpy/memmove/memset
intrinsics. This change updates the polly tests for this change.

 The @llvm.memcpy/memmove/memset intrinsics currently have an explicit argument
which is required to be a constant integer. It represents the alignment of the
dest (and source), and so must be the minimum of the actual alignment of the
two.

 This change removes the alignment argument in favour of placing the alignment
attribute on the source and destination pointers of the memory intrinsic call.

 For example, code which used to read:
  call void @llvm.memcpy.p0i8.p0i8.i32(i8* %dest, i8* %src, i32 100, i32 4, i1 false)
will now read
  call void @llvm.memcpy.p0i8.p0i8.i32(i8* align 4 %dest, i8* align 4 %src, i32 100, i1 false)

 At this time the source and destination alignments must be the same (Step 1).
Step 2 of the change, to be landed shortly, will relax that contraint and allow
the source and destination to have different alignments.

llvm-svn: 322963
2018-01-19 17:12:48 +00:00
Michael Kruse 9cfb0ac223 [ScopBuilder] Revise statement naming when there are multiple statements per BB.
The goal is to have -polly-stmt-granularity=bb and
-polly-stmt-granularity=scalar-indep to have the same names if there is
just one statement per basic block.

This fixes a fluke when Polybench's jacobi-2d is optimized differently
depending on the -polly-stmt-granularity option, although both options
create the same SCoP, just with different statement names.

The new naming scheme is:

With -polly-use-llvm-names=0:
Stmt<BBIdx as decimal><Idx within BB as letter>

With -polly-use-llvm-names=1:
Stmt_BBName_<Idx within BB as letter>

The <Idx within BB> suffix is omitted for the main statement of a BB. The
main statement is either the one containing the first store or call
(those cannot be removed by the simplifyer), or if there is no such
instruction, the first. If after simplification there is just a single
statement left, it should be the main statement and have the same names as
with -polly-stmt-granularity=bb.

Differential Revision: https://reviews.llvm.org/D42136

llvm-svn: 322852
2018-01-18 15:15:50 +00:00
Eli Friedman a75d53c83f [polly] [ScopInfo] Don't use isl_val_get_num_si.
isl_val_get_num_si crashes on overflow, so don't use it on arbitrary
integers.

Testcase only crashes on platforms where long is 32 bits because of the
signature of isl_val_get_num_si; not sure if it's possible to write a
testcase which crashes if long is 64 bits.

There are a few other places in polly which use isl_val_get_num_si;
they probably need to be fixed as well. I don't think polly uses any
of the other "long" isl APIs in an unsafe manner.

Differential Revision: https://reviews.llvm.org/D42129

llvm-svn: 322766
2018-01-17 21:59:02 +00:00
Michael Kruse 5f0e8a46cf [ScopBuilder] Split statements on encountering store instructions.
Introduce -polly-stmt-granularity=store option.

Contributed-by: Nandini Singhal <cs15mtech01004@iith.ac.in>

Differential Revision: https://reviews.llvm.org/D37337

llvm-svn: 320360
2017-12-11 12:51:24 +00:00
Michael Kruse cc345e6e94 [ScopBuilder] Introduce -polly-stmt-granularity=scalar-indep option.
The option splits BasicBlocks into minimal statements such that no
additional scalar dependencies are introduced.

The algorithm is based on a union-find structure, and unites sets if
putting them into separate statements would introduce a scalar
dependencies. As a consequence, instructions may be split into separate
statements such their relative order is different than the statements
they are in. This is accounted for instructions whose relative order
matters (e.g. memory accesses).

The algorithm is generic in that heuristic changes can be made
relatively easily. We might relax the order requirement for read-reads
or accesses to different base pointers. Forwardable instructions can be
made to not cause a join.

This implementation gives us a speed-up of 82% in SPEC 2006 456.hmmer
benchmark by allowing loop-distribution in a hot loop such that one of
the loops can be vectorized.

Differential Revision: https://reviews.llvm.org/D38403

llvm-svn: 314983
2017-10-05 13:43:00 +00:00
Michael Kruse f5745b4e7d [ScopBuilder] Build invariant loads separately.
Create the MemoryAccesses of invariant loads separately and before
all other MemoryAccesses.

Invariant loads are classified as synthesizable and therefore are not
contained in any statement. When iterating over all instructions of all
statements, the invariant loads are consequently not processed and
iterating over them separately becomes necessary.

This patch can change the order in which MemoryAccesses are created, but
otherwise has no functional change.

Some temporary code is introduced to ensure correctness, but will be
removed in the next commit.

llvm-svn: 314664
2017-10-02 11:41:27 +00:00
Michael Kruse 89a6f3db02 [ScopBuilder] Build escaping dependencies separately.
Instructions that compute escaping values might be synthesizable and
therefore not contained in any ScopStmt. When buildAccessFunctions is
changed to only iterate over the instruction list of statement,
"free" instructions still need to be written. We do this after the
main MemoryAccesses have been created.

This can change the order in which MemoryAccesses are created, but has
otherwise no functional change.

llvm-svn: 314663
2017-10-02 11:41:19 +00:00
Tobias Grosser 1f93d0f1f9 [ScopInfo] Allow PHI nodes that reference an error block
As long as these PHI nodes are only referenced by terminator instructions.

llvm-svn: 314212
2017-09-26 15:00:10 +00:00
Tobias Grosser 5e531dfef4 [ScopInfo] Allow invariant loads in branch conditions
In case the value used in a branch condition is a load instruction, assume this
load to be invariant.

llvm-svn: 314146
2017-09-25 20:27:15 +00:00