As our delinearization works optimistically, we need in some cases run-time
checks that verify our optimistic assumptions. A simple example is the
following code:
void foo(long n, long m, long o, double A[n][m][o]) {
for (long i = 0; i < 100; i++)
for (long j = 0; j < 150; j++)
for (long k = 0; k < 200; k++)
A[i][j][k] = 1.0;
}
After clang linearized the access to A and we delinearized it again to
A[i][j][k] we need to ensure that we do not access the delinearized array
out of bounds (this information is not available in LLVM-IR). Hence, we
need to verify the following constraints at run-time:
CHECK: Assumed Context:
CHECK: [o, m] -> { : m >= 150 and o >= 200 }
llvm-svn: 212198
To translate the old induction variables as they exist before Polly to new
new induction variables introduced during AST code generation we need to
generate code that computes the new values from the old ones. We can do this
by just looking at the arguments isl generates in each scheduled statement.
Example:
// Old
for i
S(i)
// New
for c0
for c1
S(c0 + c1)
To get the value of i, we need to compute 'c0 + c1'. This expression is readily
available in the user statements generated by isl and just needs to be
translated to LLVM-IR.
This replaces an old confusing construct that constructed during ast generation
an isl multi affine expression that described this relation and which was then
again ast generated for each statement and argument when translating the isl ast
to LLVM-IR. This approach was difficult to understand and the additional ast
generation calls where entirely redundant as isl provides the relevant
expressions as arguments of the generated user statements.
llvm-svn: 212186
This change is particularly useful in the code generation as we need
to know which binary operator/identity element we need to combine/initialize
the privatization locations.
+ Print the reduction type for each memory access
+ Adjusted the test cases to comply with the new output format and
to test for the right reduction type
llvm-svn: 212126
Iterate over all store memory accesses and check for valid binary reduction
candidate loads by following the operands of the stored value. For each
candidate pair we check if they have the same base address and there are no
other accesses which may overlap with them. This ensures that no intermediate
value can escape into other memory locations or is overwritten at some point.
+ 17 test cases for reduction detection and reduction dependency modeling
llvm-svn: 211957
Enabling -keep-going in ScopDetection causes expansion to an invalid
Scop candidate.
Region A <- Valid candidate
|
Region B <- Invalid candidate
If -keep-going is enabled, ScopDetection would expand A to A+B because
the RejectLog is never checked for errors during expansion.
With this patch only A becomes a valid Scop.
llvm-svn: 211875
This dependency analysis will keep track of memory accesses if they might be
part of a reduction. If not, the dependences are tracked on a statement level.
The main reason to do this is to reduce the compile time while beeing able to
distinguish the effects of reduction and non-reduction accesses.
+ Adjusted two test cases
llvm-svn: 211794
Use a container class to store the reject logs. Delegating most calls to
the internal std::map and add a few convenient shortcuts (e.g.,
hasErrors()).
llvm-svn: 211780
Add support for generating optimization remarks after completing the
detection of Scops.
The goal is to provide end-users with useful hints about opportunities that
help to increase the size of the detected Scops in their code.
By default the remark is unspecified and the debug location is empty. Future
patches have to expand on the messages generated.
This patch brings a simple test case for ReportFuncCall to demonstrate the
feature.
Reports all missed opportunities to increase the size/number of valid
Scops:
clang <...> -Rpass-missed="polly-detect" <...>
opt <...> -pass-remarks-missed="polly-detect" <...>
Reports beginning and end of all valid Scops:
clang <...> -Rpass="polly-detect" <...>
opt <...> -pass-remarks="polly-detect" <...>
Differential Revision: http://reviews.llvm.org/D4171
llvm-svn: 211769
We use llvm.codegen intrinsic to generate code for embedded LLVM-IR
strings. The reason we introduce such a intrinsic is that previous
clang/opt tools was NOT linked with various LLVM targets and their
AsmParsers and AsmPrinters. Since clang/opt been linked with all the
needed libraries, we no longer need the llvm.codegen intrinsic.
llvm-svn: 211573
+ Collect reduction dependences
+ Introduced TYPE_RED in Dependences.h which can be used to obtain the
reduction dependences
+ Used TYPE_RED to prevent parallelization while we do not have a privatizing
code generation
+ Relax the dependences for non-parallel code generation
+ Add privatization dependences to ensure correctness
+ 12 Test cases to check for reduction and privatization dependences
llvm-svn: 211369
+ Flag to indicate reduction like statements
+ Command line option to (dis)allow multiplicative reduction opcodes
+ Two simple positive test cases, one fp test case w and w/o fast math
+ One "negative" test case (only reduction like but no reduction)
llvm-svn: 211114
+ Added const iterator version
+ Changed name to begin/end to allow range loops
+ Changed call sites to range loops
+ Changed typename to (const_)iterator
llvm-svn: 210927
In general this fixes ambiguity that can arise from using
a different namespace that declares the same symbols as
we do.
One example inside llvm would be:
createIndVarSimplifyPass(..);
Which can be found in:
llvm/Transforms/Scalar.h
and
polly/LinkAllPasses.h
llvm-svn: 210755
Without this patch, the testcase would fail on the delinearization of the second
array:
; void foo(long n, long m, long o, double A[n][m][o]) {
; for (long i = 0; i < n; i++)
; for (long j = 0; j < m; j++)
; for (long k = 0; k < o; k++) {
; A[i+3][j-4][k+7] = 1.0;
; A[i][0][k] = 2.0;
; }
; }
; CHECK: [n, m, o] -> { Stmt_for_body6[i0, i1, i2] -> MemRef_A[3 + i0, -4 + i1, 7 + i2] };
; CHECK: [n, m, o] -> { Stmt_for_body6[i0, i1, i2] -> MemRef_A[i0, 0, i2] };
Here is the output of FileCheck on the testcase without this patch:
; CHECK: [n, m, o] -> { Stmt_for_body6[i0, i1, i2] -> MemRef_A[i0, 0, i2] };
^
<stdin>:26:2: note: possible intended match here
[n, m, o] -> { Stmt_for_body6[i0, i1, i2] -> MemRef_A[o0] };
^
It is possible to find a good delinearization for A[i][0][k] only in the context
of the delinearization of both array accesses.
There are two ways to delinearize together all array subscripts touching the
same base address: either duplicate the code from scop detection to first gather
all array references and then run the delinearization; or as implemented in this
patch, use the same delinearization info that we computed during scop detection.
llvm-svn: 210117
Instead of relying on the delinearization to infer the size of an element,
compute the element size from the base address type. This is a much more precise
way of computing the element size than before, as we would have mixed together
the size of an element with the strides of the innermost dimension.
llvm-svn: 209695
Support a 'keep-going' mode for the ScopDetection. In this mode, we just keep
on detecting, even if we encounter an error.
This is useful for diagnosing SCoP candidates. Sometimes you want all the
errors. Invalid SCoPs will still be refused in the end, we just refuse to
abort on the first error.
llvm-svn: 209574
This stores all RejectReasons created for one region
in a RejectLog inside the DetectionContext. For now
this only keeps track of the last error.
A separate patch will enable the tracking of all errors.
This patch itself does no harm (yet).
llvm-svn: 209572
definition below all of the header #include lines, Polly edition.
If you want to know more details about this, you can see the recent
commits to Debug.h in LLVM. This is just the Polly segment of a cleanup
I'm doing globally for this macro.
llvm-svn: 206852
We only supported a very old version of OpenScop that was entirely different
to what OpenScop is today. To not confuse people, we remove this old and
unusable support. If anyone is interested to add OpenScop support back in,
the relevant patches are available in version control.
llvm-svn: 206026
This replaces the ancient INVALID/INVALID_NOVERIFY macros with a real
function.
The new invalid(..) function uses small diagnostic objects that are
generated on demand. We can store arbitrary additional information per
error type and generate useful debug/error messages on the fly.
Use it as follows:
if (/* Some error condition (ReportFoo) */)
invalid<ReportFoo>(Context, /*Assert=*/true/false,
(/* List of helpful diagnostic objects */));
Where ReportFoo is a subclass of RejectReason that is able to take the
list of helpful diagnostic objects in its constructor.
The implementation of invalid will create the report and fire
an assertion, if necessary.
llvm-svn: 205414
This patch enables vectorization of loops containing backward array
traversal (array stride is -1).
Contributed-by: Chris Jenneisch <chrisj@codeaurora.org>
llvm-svn: 204257
This ensures that the polly passes get properly registered both, when using
polly as a loadable module and when directly linking it into clang/opt/bugpoint.
llvm-svn: 204255
1) The isl_int -> isl_val changes are the ones Tobias suggested.
One additional isl_val_free is added (and needed)
2) Three scoplib_vector_free are added, maybe we would need even
more (and matrix_free) but it's hard to place them right.
3) Cleaned the includes (and removed 'extern C')
This fixes the broken compilation for the scoplib import and export.
Contributed-by: Johannes Doerfert <doerfert@cs.uni-saarland.de>
llvm-svn: 203500
We currently need to always name instructions, as the polly test suite currently
matches for certain names. We should improve the test suite at some point.
This fixes 'make check-polly' in NDEBUG builds.
llvm-svn: 202855
For now we only mark innermost loops for the loop vectorizer. We could later
also mark not-innermost loops to enable the introduction of openmp parallelism.
llvm-svn: 202854
PollyIRBuilder is currently just a typedef to IRBuilder<>. Consequently, this
change should not affect behavior. In subsequent patches we will extend its
functionality to emit loop.parallel metadata.
llvm-svn: 202853
This fixes the buildbots who failed, because the linker eliminated most of the
Polly functionality when building without BUILD_SHARED_LIBS=ON.
Besides fixing the build, this change also brings additional functionality. With
the new separation between the general polly libraries and the functionality for
the polly module, it is now possible to link polly directly into a tool instead
of using requiring users to load a shared library.
llvm-svn: 202762
clang-formats behaviour has changed for a couple of C++11 formattings. We adapt
Polly to ensure our formatting checks are clean again.
llvm-svn: 202650
Tobias Grosser