llvm-svn: 167130

BBVectorize would, except for loads and stores, always fuse instructions
so that the first instruction (in the current source order) would always
represent the low part of the input vectors and the second instruction
would always represent the high part. This lead to too many shuffles
being produced because sometimes the opposite order produces fewer of them.

With this change, BBVectorize tracks the kind of pair connections that form
the DAG of candidate pairs, and uses that information to reorder the pairs to
avoid excess shuffles. Using this information, a future commit will be able
to add VTTI-based shuffle costs to the pair selection procedure. Importantly,
the number of remaining shuffles can now be estimated during pair selection.

There are some trivial instruction reorderings in the test cases, and one
simple additional test where we certainly want to do a reordering to
avoid an unnecessary shuffle.

llvm-svn: 167122

 - Use 0 instead of NULL
 - Helper function for "dyn_cast, else lookup in the constant pool".

llvm-svn: 167121

This patch migrates the strto* optimizations from the simplify-libcalls
pass into the instcombine library call simplifier.

llvm-svn: 167119

llvm-svn: 167117

No functionality change.

llvm-svn: 167116

By propagating the value for the switch condition, LLVM can now build
lookup tables for code such as:

  switch (x) {
    case 1: return 5;
    case 2: return 42;
    case 3: case 4: case 5:
      return x - 123;
    default:
      return 123;
  }

Given that x is known for each case, "x - 123" becomes a constant for
cases 3, 4, and 5.

llvm-svn: 167115

I'm not entirely happy with this solution, but I don't see a smarter way currently.
Fixes PR14214.

llvm-svn: 167112

This patch migrates the strpbrk optimizations from the simplify-libcalls
pass into the instcombine library call simplifier.

llvm-svn: 167105

This patch migrates the strlen optimizations from the simplify-libcalls
pass into the instcombine library call simplifier.

llvm-svn: 167103

This patch migrates the strncpy optimizations from the simplify-libcalls
pass into the instcombine library call simplifier.

llvm-svn: 167102

llvm-svn: 167101

This is important for loops in the LAPACK test-suite.
These loops start at 1 because they are auto-converted from fortran.

llvm-svn: 167084

This patch migrates the stpcpy optimizations from the simplify-libcalls
pass into the instcombine library call simplifier.  Note that the
__stpcpy_chk simplifications were migrated in a previous commit.

llvm-svn: 167083

r166198 migrated the strcpy optimization to instcombine.  The strcpy
simplifier that was migrated from Transforms/Scalar/SimplifyLibCalls.cpp
was also doing some __strcpy_chk simplifications.  Those fortified
simplifications were migrated as well, but introduced a bug in the
__stpcpy_chk simplifier in the process.  This happened because the
__strcpy_chk and __stpcpy_chk simplifiers were both mapped to StrCpyChkOpt
which was updated with simplifications that worked for __strcpy_chk, but
not __stpcpy_chk.

This patch fixes the problem by adding proper test coverage and creating a
new simplifier for __stpcpy_chk (instead of sharing one with __strcpy_chk).

llvm-svn: 167082

llvm-svn: 167055

integers in that the code to handle split alloca-wide integer loads or
stores doesn't come first. It should, for the same reasons as with
integers, and the PR attests to that. Also had to fix a busted assert in
that this test case also covers.

llvm-svn: 167051

Instead of recomputing relative pointer information just prior to fusing,
cache this information (which also needs to be computed during the
candidate-pair selection process). This cuts down on the total number of
SE queries made, and also is a necessary intermediate step on the road toward
including shuffle costs in the pair selection procedure.

No functionality change is intended.

llvm-svn: 167049

Thanks to Preston Briggs for catching this!

llvm-svn: 167045

We need to make sure that we take the correct load/store alignment
when the inputs are flipped.

llvm-svn: 167044

Stop propagating the FlipMemInputs variable into the routines that
create the replacement instructions. Instead, just flip the arguments
of those routines. This allows for some associated cleanup (not all
of which is done here). No functionality change is intended.

llvm-svn: 167042

SE was being called during the instruction-fusion process (when the result
is unreliable, and thus ignored). No functionality change is intended.

llvm-svn: 167037

llvm-svn: 167036

Speedup SciMark by 1%

llvm-svn: 167035

LoopVectorize: Fix a bug in the initialization of reduction variables. AND needs to start at all-one
while XOR, and OR need to start at zero.

llvm-svn: 167032

with different sizes.

llvm-svn: 167018

This fixes Clang :: CodeGen/complex-builtints.c on PowerPC.

llvm-svn: 167013

When the switch-to-lookup tables transform landed in SimplifyCFG, it
was pointed out that this could be inappropriate for some targets.
Since there was no way at the time for the pass to know anything about
the target, an awkward reverse-transform was added in CodeGenPrepare
that turned lookup tables back into switches for some targets.

This patch uses the new TargetTransformInfo to determine if a
switch should be transformed, and removes
CodeGenPrepare::ConvertLoadToSwitch.

llvm-svn: 167011

LoopVectorizer: change debug prints: Print the module identifier when deciding to vectorize. When deciding not to vectorize do not print the called function name because it can be null.

llvm-svn: 166989

llvm-svn: 166970

checks to avoid performing compile-time arithmetic on PPCDoubleDouble.

Now that APFloat supports arithmetic on PPCDoubleDouble, those checks
are no longer needed, and we can treat the type like any other.

llvm-svn: 166958

llvm-svn: 166948

wrapper returns a vector of integers when passed a vector of pointers) by having
getIntPtrType itself return a vector of integers in this case.  Outside of this
wrapper, I didn't find anywhere in the codebase that was relying on the old
behaviour for vectors of pointers, so give this a whirl through the buildbots.

llvm-svn: 166939

Change the PassManagerBuilder (used by -O3) loop vectorizer flag from -vectorize to -vectorize-loops because we dont want to share the same flag as the bb-vectorizer.

llvm-svn: 166937

split module can see each other. If it is keeping a symbol that already has
a non local linkage, it doesn't need to change it.

llvm-svn: 166908

output of both

llvm-extract foo.ll -func=bar
and
llvm-extract foo.ll -func=bar -delete

so the two new files could not be linked together anymore. With this change
alias are handled almost like functions and global variables. Almost because
with alias we cannot just clear the initializer/body, we have to create a new
declaration and replace the alias with it.

The net result is that now the output of the above commands can be linked
even if foo.ll has aliases.

llvm-svn: 166907

I don't think this is possible with the current implementation but that may change eventually.

llvm-svn: 166877

This turns loops like
  for (unsigned i = 0; i != n; ++i)
    p[i] = p[i+1];
into memmove, which has a highly optimized implementation in most libcs.

This was really easy with the new DependenceAnalysis :)

llvm-svn: 166875

Requires a lot less code and complexity on loop-idiom's side and the more
precise analysis can catch more cases, like the one I included as a test case.
This also fixes the edge-case miscompilation from PR9481.

Compile time performance seems to be slightly worse, but this is mostly due
to an extra LCSSA run scheduled by the PassManager and should be fixed there.

llvm-svn: 166874

The monolithic interface for instruction costs has been split into
several functions. This is the corresponding change. No functionality
change is intended.

llvm-svn: 166865