llvm-svn: 183243

IndVarSimplify is willing to move divide instructions outside of their
loop bodies if they are invariant of the loop.  However, it may not be
safe to expand them if we do not know if they can trap.

Instead, check to see if it is not safe to expand the instruction and
skip the expansion.

This fixes PR16041.

Testcase by Rafael Ávila de Espíndola.

llvm-svn: 183239

The ARM backend did not expect LDRBi12 to hold a constant pool operand.
Allow for LLVM to deal with the instruction similar to how it deals with
LDRi12.

This fixes PR16215.

llvm-svn: 183238

llvm-svn: 183229

The problem this time seems to be a thinko. We were assuming that in the CFG

A
| \
|  B
| /
C

speculating the basic block B would cause only the phi value for the B->C edge
to be speculated. That is not true, the phi's are semantically in the edges, so
if the A->B->C path is taken, any code needed for A->C is not executed and we
have to consider it too when deciding to speculate B.

llvm-svn: 183226

llvm-svn: 183219

GCC complains about casting away const.

llvm-svn: 183216

Test commit for user vmedic, to verify commit access. One line of comment is added to MipsAsmParser.cpp.

llvm-svn: 183215

llvm-svn: 183176

llvm-svn: 183175

(4.58s vs 3.2s on an oldish Mac Tower). 

  The corresponding src is excerpted bellow. The lopp accounts for about 90% of execution time.
  --------------------
    cat -n test-suite/MultiSource/Benchmarks/Olden/em3d/make_graph.c
     90 
     91         for (k=0; k<j; k++)
     92           if (other_node == cur_node->to_nodes[k]) break;

  The defective layout is sketched bellow, where the two branches need to swap.
  ------------------------------------------------------------------------
      L:
         ...
      if (cond) goto out-of-loop
      goto L

  While this code sequence is defective, I don't understand why it incurs 1/3 of 
execution time. CPU-event-profiling indicates the poor laoyout dose not increase
in br-misprediction; it dosen't increase stall cycle at all, and it dosen't 
prevent the CPU detect the loop (i.e. Loop-Stream-Detector seems to be working fine
as well)... 

   The root cause of the problem is that the layout pass calls AnalyzeBranch() 
with basic-block which is not updated to reflect its current layout.

rdar://13966341

llvm-svn: 183174

llvm-svn: 183167

PR16069 is an interesting case where an incoming value to a PHI is a
trap value while also being a 'ConstantExpr'.

We do not consider this case when performing the 'HoistThenElseCodeToIf'
optimization.

Instead, make our modifications more conservative if we detect that we
cannot transform the PHI to a select.

llvm-svn: 183152

llvm-svn: 183151

This was missing from r182908. I didn't noticed it at the time because the MCJIT tests were
disabled when building with cmake on ppc64 (which I fixed in r183143).

llvm-svn: 183147

llvm-svn: 183138

llvm-svn: 183137

llvm-svn: 183136

This is necessary to avoid generating VGPR to SGPR copies in some
cases.

llvm-svn: 183135

llvm-svn: 183134

llvm-svn: 183133

The CopyToReg nodes will sometimes try to copy a value from a VGPR to an
SGPR.  This kind of copy is not possible, so we need to detect
VGPR->SGPR copies and do something else.  The current strategy is to
replace these copies with VGPR->VGPR copies and hope that all the users
of CopyToReg can accept VGPRs as arguments.

llvm-svn: 183132

llvm-svn: 183131

The lowering of stores is now mostly handled in the tablegen files.  No
more BUFFER_STORE nodes I generated during legalization.

llvm-svn: 183130

llvm-svn: 183111

llvm-svn: 183108

llvm-svn: 183107

llvm-svn: 183106

llvm-svn: 183104

llvm-svn: 183103

This is needed in clang so one can check if the object needs the
destructor called after its memory was freed. This is useful when
creating many APInt/APFloat objects with placement new, where the
overhead of tracking the pointers for cleanup is significant.

llvm-svn: 183100

llvm-svn: 183094

llvm-svn: 183091

       using two instructions (sethi and store).

llvm-svn: 183090

llvm-svn: 183088

llvm-svn: 183083

index greater than the size of the vector is invalid. The shuffle may be
shrinking the size of the vector. Fixes a crash!

Also drop the maximum recursion depth of the safety check for this
optimization to five.

llvm-svn: 183080

llvm-svn: 183079

llvm-svn: 183078

Also simplify code a bit while there. No functionality change.

llvm-svn: 183076