286 Commits

Author SHA1 Message Date
Arnold Schwaighofer
84875bad9c LoopVectorizer: Change variable name Stride to ConsecutiveStride
This makes it easier to read the code.

No functionality change.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@180197 91177308-0d34-0410-b5e6-96231b3b80d8
2013-04-24 16:16:03 +00:00
Arnold Schwaighofer
a4b8b4ccc9 LoopVectorize: Scalarize padded types
This patch disables memory-instruction vectorization for types that need padding
bytes, e.g., x86_fp80 has 10 bytes store size with 6 bytes padding in darwin on
x86_64. Because the load/store vectorization is performed by the bit casting to
a packed vector, which has incompatible memory layout due to the lack of padding
bytes, the present vectorizer produces inconsistent result for memory
instructions of those types.
This patch checks an equality of the AllocSize of a scalar type and allocated
size for each vector element, to ensure that there is no padding bytes and the
array can be read/written using vector operations.

Patch by Daisuke Takahashi!

Fixes PR15758.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@180196 91177308-0d34-0410-b5e6-96231b3b80d8
2013-04-24 16:16:01 +00:00
Arnold Schwaighofer
b03ad17536 LoopVectorizer: Bail out if we don't have datalayout we need it
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@180195 91177308-0d34-0410-b5e6-96231b3b80d8
2013-04-24 16:15:58 +00:00
Nadav Rotem
a7d9a6ee63 LoopVectorizer: Fix 15830. When scalarizing and unrolling stores make sure that the order in which the elements are scalarized is the same as the original order.
This fixes a miscompilation in FreeBSD's regex library.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@180121 91177308-0d34-0410-b5e6-96231b3b80d8
2013-04-23 17:12:42 +00:00
Pekka Jaaskelainen
2e59a125fc Call the potentially costly isAnnotatedParallel() only once.
Made the uniform write test's checks a bit stricter.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@180119 91177308-0d34-0410-b5e6-96231b3b80d8
2013-04-23 16:44:43 +00:00
Pekka Jaaskelainen
a8958769ea Refuse to (even try to) vectorize loops which have uniform writes,
even if erroneously annotated with the parallel loop metadata.

Fixes Bug 15794: 
"Loop Vectorizer: Crashes with the use of llvm.loop.parallel metadata"



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@180081 91177308-0d34-0410-b5e6-96231b3b80d8
2013-04-23 08:08:51 +00:00
Eric Christopher
3e39731e88 Move C++ code out of the C headers and into either C++ headers
or the C++ files themselves. This enables people to use
just a C compiler to interoperate with LLVM.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@180063 91177308-0d34-0410-b5e6-96231b3b80d8
2013-04-22 22:47:22 +00:00
Nadav Rotem
b86dff862f SLPVectorize: Add support for vectorization of casts.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@179975 91177308-0d34-0410-b5e6-96231b3b80d8
2013-04-21 08:05:59 +00:00
Nadav Rotem
bd65805016 SLPVectorizer: Fix a bug in the code that scans the tree in search of nodes with multiple users.
We did not terminate the switch case and we executed the search routine twice.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@179974 91177308-0d34-0410-b5e6-96231b3b80d8
2013-04-21 07:37:56 +00:00
Nadav Rotem
4f38e16b89 Fix PR15800. Do not try to vectorize vectors and structs.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@179960 91177308-0d34-0410-b5e6-96231b3b80d8
2013-04-20 22:29:43 +00:00
Benjamin Kramer
d760c08b34 VecUtils: Clean up uses of dyn_cast.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@179936 91177308-0d34-0410-b5e6-96231b3b80d8
2013-04-20 10:36:17 +00:00
Benjamin Kramer
6fe5cc49d8 SLPVectorizer: Strength reduce SmallVectors to ArrayRefs.
Avoids a couple of copies and allows more flexibility in the clients.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@179935 91177308-0d34-0410-b5e6-96231b3b80d8
2013-04-20 09:49:10 +00:00
Nadav Rotem
cd949714eb SLPVectorizer: Reduce the compile time by eliminating the search for some of the more expensive patterns. After this change will only check basic arithmetic trees that start at cmpinstr.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@179933 91177308-0d34-0410-b5e6-96231b3b80d8
2013-04-20 07:29:34 +00:00
Nadav Rotem
444e33e898 refactor tryToVectorizePair to a new method that supports vectorization of lists.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@179932 91177308-0d34-0410-b5e6-96231b3b80d8
2013-04-20 07:22:58 +00:00
Nadav Rotem
d7e8cce287 Fix an unused variable warning.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@179931 91177308-0d34-0410-b5e6-96231b3b80d8
2013-04-20 06:40:28 +00:00
Nadav Rotem
1d2ad834f2 SLPVectorizer: Improve the cost model for loop invariant broadcast values.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@179930 91177308-0d34-0410-b5e6-96231b3b80d8
2013-04-20 06:13:47 +00:00
Nadav Rotem
ef332b1ca1 Report the number of stores that were found in the debug message.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@179929 91177308-0d34-0410-b5e6-96231b3b80d8
2013-04-20 05:23:11 +00:00
Nadav Rotem
2aaa269617 Fix the header comment.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@179928 91177308-0d34-0410-b5e6-96231b3b80d8
2013-04-20 05:18:51 +00:00
Nadav Rotem
fbcaf59e33 Use 64bit arithmetic for calculating distance between pointers.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@179927 91177308-0d34-0410-b5e6-96231b3b80d8
2013-04-20 05:17:47 +00:00
Arnold Schwaighofer
d717e202a2 LoopVectorizer: Use matcher from PatternMatch.h for the min/max patterns
Also make some static function class functions to avoid having to mention the
class namespace for enums all the time.

No functionality change intended.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@179886 91177308-0d34-0410-b5e6-96231b3b80d8
2013-04-19 21:03:36 +00:00
Dmitri Gribenko
4b15d6ae49 Fix a -Wdocumentation warning
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@179789 91177308-0d34-0410-b5e6-96231b3b80d8
2013-04-18 20:13:04 +00:00
Arnold Schwaighofer
a3fb330d05 LoopVectorizer: Recognize min/max reductions
A min/max operation is represented by a select(cmp(lt/le/gt/ge, X, Y), X, Y)
sequence in LLVM. If we see such a sequence we can treat it just as any other
commutative binary instruction and reduce it.

This appears to help bzip2 by about 1.5% on an imac12,2.

radar://12960601

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@179773 91177308-0d34-0410-b5e6-96231b3b80d8
2013-04-18 17:22:34 +00:00
Benjamin Kramer
403fc14370 LoopVectorize: Use a set to avoid longer cycles in the reduction chain too.
Fixes PR15748.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@179757 91177308-0d34-0410-b5e6-96231b3b80d8
2013-04-18 14:29:13 +00:00
Nadav Rotem
e9a4411db4 SLPVectorizer: Make it a function pass and add code for hoisting the vector-gather sequence out of loops.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@179562 91177308-0d34-0410-b5e6-96231b3b80d8
2013-04-15 22:00:26 +00:00
Nadav Rotem
09616565dd SLPVectorizer: Add support for vectorizing trees that start at compare instructions.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@179504 91177308-0d34-0410-b5e6-96231b3b80d8
2013-04-15 04:25:27 +00:00
Benjamin Kramer
e197486908 Miscellaneous cleanups for VecUtils.h
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@179483 91177308-0d34-0410-b5e6-96231b3b80d8
2013-04-14 09:33:08 +00:00
Nadav Rotem
0774629936 SLP: Document the scalarization cost method.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@179479 91177308-0d34-0410-b5e6-96231b3b80d8
2013-04-14 07:22:22 +00:00
Nadav Rotem
ab105ae95f SLPVectorizer: Add support for trees that don't start at binary operators, and add the cost of extracting values from the roots of the tree.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@179475 91177308-0d34-0410-b5e6-96231b3b80d8
2013-04-14 05:15:53 +00:00
Nadav Rotem
f7eaf29cf7 SLPVectorizer: add initial support for reduction variable vectorization.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@179470 91177308-0d34-0410-b5e6-96231b3b80d8
2013-04-14 03:22:20 +00:00
Nadav Rotem
a74f91e44c SLPVectorizer: add support for vectorization of diamond shaped trees. We now perform a preliminary traversal of the graph to collect values with multiple users and check where the users came from.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@179414 91177308-0d34-0410-b5e6-96231b3b80d8
2013-04-12 21:16:54 +00:00
Nadav Rotem
196ee11f85 Add debug prints.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@179412 91177308-0d34-0410-b5e6-96231b3b80d8
2013-04-12 21:11:14 +00:00
Arnold Schwaighofer
08a0e8f8db LoopVectorizer: integer division is not a reduction operation
Don't classify idiv/udiv as a reduction operation. Integer division is lossy.
For example : (1 / 2) * 4 != 4/2.

Example:

int a[] = { 2, 5, 2, 2}
int x = 80;

for()
  x /= a[i];

Scalar:
  x /= 2 // = 40
  x /= 5 // = 8
  x /= 2 // = 4
  x /= 2 // = 2

Vectorized:

 <80, 1> / <2,5> //= <40,0>
 <40, 0> / <2,2> //= <20,0>

 20*0 = 0

radar://13640654

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@179381 91177308-0d34-0410-b5e6-96231b3b80d8
2013-04-12 15:15:19 +00:00
Benjamin Kramer
acc897a5e1 Rename the C function to create a SLPVectorizerPass to something sane and expose it in the header file.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@179272 91177308-0d34-0410-b5e6-96231b3b80d8
2013-04-11 11:36:36 +00:00
Nadav Rotem
4b924d3a61 Make the SLP store-merger less paranoid about function calls. We check for function calls when we check if it is safe to sink instructions.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@179207 91177308-0d34-0410-b5e6-96231b3b80d8
2013-04-10 19:41:36 +00:00
Nadav Rotem
20cd5e6862 We require DataLayout for analyzing the size of stores.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@179206 91177308-0d34-0410-b5e6-96231b3b80d8
2013-04-10 18:57:27 +00:00
Nadav Rotem
8383b539ff Add support for bottom-up SLP vectorization infrastructure.
This commit adds the infrastructure for performing bottom-up SLP vectorization (and other optimizations) on parallel computations.
The infrastructure has three potential users:

  1. The loop vectorizer needs to be able to vectorize AOS data structures such as (sum += A[i] + A[i+1]).

  2. The BB-vectorizer needs this infrastructure for bottom-up SLP vectorization, because bottom-up vectorization is faster to compute.

  3. A loop-roller needs to be able to analyze consecutive chains and roll them into a loop, in order to reduce code size. A loop roller does not need to create vector instructions, and this infrastructure separates the chain analysis from the vectorization.

This patch also includes a simple (100 LOC) bottom up SLP vectorizer that uses the infrastructure, and can vectorize this code:

void SAXPY(int *x, int *y, int a, int i) {
  x[i]   = a * x[i]   + y[i];
  x[i+1] = a * x[i+1] + y[i+1];
  x[i+2] = a * x[i+2] + y[i+2];
  x[i+3] = a * x[i+3] + y[i+3];
}



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@179117 91177308-0d34-0410-b5e6-96231b3b80d8
2013-04-09 19:44:35 +00:00
Arnold Schwaighofer
ac2cc0170f LoopVectorizer: Pass OperandValueKind information to the cost model
Pass down the fact that an operand is going to be a vector of constants.

This should bring the performance of MultiSource/Benchmarks/PAQ8p/paq8p on x86
back. It had degraded to scalar performance due to my pervious shift cost change
that made all shifts expensive on x86.

radar://13576547

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@178809 91177308-0d34-0410-b5e6-96231b3b80d8
2013-04-04 23:26:27 +00:00
Arnold Schwaighofer
d517da33b7 LoopVectorize: Invert case when we use a vector cmp value to query select cost
We generate a select with a vectorized condition argument when the condition is
NOT loop invariant. Not the other way around.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@177098 91177308-0d34-0410-b5e6-96231b3b80d8
2013-03-14 18:54:36 +00:00
Hal Finkel
76a05c93b1 BBVectorize: Fixup debugging statements
After the recent data-structure improvements, a couple of debugging statements
were broken (printing pointer values).

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@176791 91177308-0d34-0410-b5e6-96231b3b80d8
2013-03-10 20:57:42 +00:00
Benjamin Kramer
0d932717d8 Remove a source of nondeterminism from the LoopVectorizer.
This made us emit runtime checks in a random order. Hopefully bootstrap
miscompares will go away now.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@176775 91177308-0d34-0410-b5e6-96231b3b80d8
2013-03-09 19:22:40 +00:00
Arnold Schwaighofer
738295e457 LoopVectorizer: Ignore all dbg intrinisic
Ignore all DbgIntriniscInfo instructions instead of just DbgValueInst.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@176769 91177308-0d34-0410-b5e6-96231b3b80d8
2013-03-09 16:27:27 +00:00
Arnold Schwaighofer
56ee544a3a LoopVectorizer: Ignore dbg.value instructions
We want vectorization to happen at -g. Ignore calls to the dbg.value intrinsic
and don't transfer them to the vectorized code.

radar://13378964

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@176768 91177308-0d34-0410-b5e6-96231b3b80d8
2013-03-09 15:56:34 +00:00
Benjamin Kramer
f22d9cfa6d Insert the reduction start value into the first bypass block to preserve domination.
Fixes PR15344.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@176701 91177308-0d34-0410-b5e6-96231b3b80d8
2013-03-08 16:58:37 +00:00
Nadav Rotem
5290baacb8 PR14448 - prevent the loop vectorizer from vectorizing the same loop twice.
The LoopVectorizer often runs multiple times on the same function due to inlining.
When this happens the loop vectorizer often vectorizes the same loops multiple times, increasing code size and adding unneeded branches.
With this patch, the vectorizer during vectorization puts metadata on scalar loops and marks them as 'already vectorized' so that it knows to ignore them when it sees them a second time.

PR14448.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@176399 91177308-0d34-0410-b5e6-96231b3b80d8
2013-03-02 01:33:49 +00:00
Benjamin Kramer
5d79bb8770 LoopVectorize: Don't hang forever if a PHI only has skipped PHI uses.
Fixes PR15384.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@176366 91177308-0d34-0410-b5e6-96231b3b80d8
2013-03-01 19:07:31 +00:00
Benjamin Kramer
2fe71f8f7e LoopVectorize: Vectorize math builtin calls.
This properly asks TargetLibraryInfo if a call is available and if it is, it
can be translated into the corresponding LLVM builtin. We don't vectorize sqrt()
yet because I'm not sure about the semantics for negative numbers. The other
intrinsic should be exact equivalents to the libm functions.

Differential Revision: http://llvm-reviews.chandlerc.com/D465

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@176188 91177308-0d34-0410-b5e6-96231b3b80d8
2013-02-27 15:24:19 +00:00
Renato Golin
e18bce5317 Allow GlobalValues to vectorize with AliasAnalysis
Storing the load/store instructions with the values
and inspect them using Alias Analysis to make sure
they don't alias, since the GEP pointer operand doesn't
take the offset into account.

Trying hard to not add any extra cost to loads and stores
that don't overlap on global values, AA is *only* calculated
if all of the previous attempts failed.

Using biggest vector register size as the stride for the
vectorization access, as we're being conservative and
the cost model (which calculates the real vectorization
factor) is only run after the legalization phase.

We might re-think this relationship in the future, but
for now, I'd rather be safe than sorry.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@175818 91177308-0d34-0410-b5e6-96231b3b80d8
2013-02-21 22:39:03 +00:00
Hal Finkel
f79f136cc6 BBVectorize: Fix an invalid reference bug
This fixes PR15289. This bug was introduced (recently) in r175215; collecting
all std::vector references for candidate pairs to delete at once is invalid
because subsequent lookups in the owning DenseMap could invalidate the
references.

bugpoint was able to reduce a useful test case. Unfortunately, because whether
or not this asserts depends on memory layout, this test case will sometimes
appear to produce valid output. Nevertheless, running under valgrind will
reveal the error.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@175397 91177308-0d34-0410-b5e6-96231b3b80d8
2013-02-17 15:59:26 +00:00
Hal Finkel
f64a7a83be BBVectorize: Call a DAG and DAG instead of a tree
Several functions and variable names used the term 'tree' to refer
to what is actually a DAG. Correcting this mistake will, hopefully,
prevent confusion in the future.

No functionality change intended.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@175278 91177308-0d34-0410-b5e6-96231b3b80d8
2013-02-15 17:20:54 +00:00
Hal Finkel
ab90084bca BBVectorize: Cap the number of candidate pairs in each instruction group
For some basic blocks, it is possible to generate many candidate pairs for
relatively few pairable instructions. When many (tens of thousands) of these pairs
are generated for a single instruction group, the time taken to generate and
rank the different vectorization plans can become quite large. As a result, we now
cap the number of candidate pairs within each instruction group. This is done by
closing out the group once the threshold is reached (set now at 3000 pairs).

Although this will limit the overall compile-time impact, this may not be the best
way to achieve this result. It might be better, for example, to prune excessive
candidate pairs after the fact the prevent the generation of short, but highly-connected
groups. We can experiment with this in the future.

This change reduces the overall compile-time slowdown of the csa.ll test case in
PR15222 to ~5x. If 5x is still considered too large, a lower limit can be
used as the default.

This represents a functionality change, but only for very large inputs
(thus, there is no regression test).

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@175251 91177308-0d34-0410-b5e6-96231b3b80d8
2013-02-15 04:28:42 +00:00