it would replace the load with one with the higher alignment.  However, it did
not place the new load in the worklist, which prevented later DAG combines in
the same phase (for example, target-specific combines) from ever seeing it.

This patch corrects that oversight, and updates some tests whose output changed
due to slightly different DAGCombine outputs.

llvm-svn: 174343

Per discussion in rdar://13127907, we should emit a hard error only if
people write code where the requested alignment is larger than achievable
and assumes the low bits are zeros. A warning should be good enough when
we are not sure if the source code assumes the low bits are zeros.

rdar://13127907

llvm-svn: 174336

This required disabling a PowerPC optimization that did the following:
input:
x = BUILD_VECTOR <i32 16, i32 16, i32 16, i32 16>
lowered to:
tmp = BUILD_VECTOR <i32 8, i32 8, i32 8, i32 8>
x = ADD tmp, tmp

The add now gets folded immediately and we're back at the BUILD_VECTOR we
started from. I don't see a way to fix this currently so I left it disabled
for now.

Fix some trivially foldable X86 tests too.

llvm-svn: 174325

Fix a bug in DAGCombine. The symptom is mistakenly optimizing expression
"x + x*x" into "x * 3.0".

llvm-svn: 174239

llvm-svn: 174237

Testing case is reduced from MultiSource/BenchMarks/Prolangs-C++/deriv1.

rdar://problem/13071590

llvm-svn: 174235

Found by Alexander Kornienko.

llvm-svn: 174207

llvm-svn: 174198

llvm-svn: 174088

past the natural stack alignment.

llvm-svn: 174085

We used to create children DIEs for a scope, then check whether ScopeDIE is
null. If ScopeDIE is null, the children DIEs will be dangling. Other DIEs can
link to those dangling DIEs, which are not emitted at all, causing dwarf error.

The current testing case is 4k lines, from MultiSource/BenchMark/McCat/09-vor.

rdar://problem/13071959

llvm-svn: 174084

Each target implementation was needlessly recomputing the index.
Part of rdar://13076458

llvm-svn: 174083

llvm-svn: 173833

Provides the functionality for Clang change r172911 - I just had this still
lying around.

llvm-svn: 173820

    
Fixed set-but-not-used warnings.

Reviewer: gribozavr
llvm-svn: 173810

llvm-svn: 173775

conditions are met:
1. They share the same operand and are in the same BB.
2. Both outputs are used.
3. The target has a native instruction that maps to ISD::FSINCOS node or
   the target provides a sincos library call.

Implemented the generic optimization in sdisel and enabled it for
Mac OSX. Also added an additional optimization for x86_64 Mac OSX by
using an alternative entry point __sincos_stret which returns the two
results in xmm0 / xmm1.

rdar://13087969
PR13204

llvm-svn: 173755

The common code in the post-RA scheduler to break anti-dependencies on the
critical path contained a flaw.  In the reported case, an anti-dependency
between the overlapping registers %X4 and %R4 exists:

	%X29<def> = OR8 %X4, %X4
	%R4<def>, %X3<def,dead,tied3> = LBZU 1, %X3<kill,tied1>

The unpatched code breaks the dependency by replacing %R4 and its uses
with %R3, the first register on the available list.  However, %R3 and
%X3 overlap, so this creates two overlapping definitions on the same
instruction.

The fix is straightforward, preventing selection of a register that
overlaps any other defined register on the same instruction.

The test case is reduced from the bug report, and verifies that we no
longer produce "lbzu 3, 1(3)" when breaking this anti-dependency.

llvm-svn: 173706

llvm-svn: 173698

Extracted ObjCARC.cpp into its own library libLLVMObjCARCOpts in preparation for refactoring the ARC Optimizer.

llvm-svn: 173647

llvm-svn: 173625

llvm-svn: 173620

Fix that by adding a cast to the shift expander. This came up with vector shifts
on sse-less X86 CPUs.

   <2 x i64>       = shl <2 x i64> <2 x i64>
-> i64,i64         = shl i64 i64; shl i64 i64
-> i32,i32,i32,i32 = shl_parts i32 i32 i64; shl_parts i32 i32 i64

Now we cast the last two i64s to the right type. Fixes the crash in PR14668.

llvm-svn: 173615

llvm-svn: 173497

with an initial number of elements,  instead of DenseMap, which has
zero initial elements, in order to avoid the copying of elements
when the size changes and to avoid allocating space every time
LegalizeTypes is run. This patch will not affect the memory footprint,
because DenseMap will increase the element size to 64
when the first element is added.

Patch by Wan Xiaofei.

llvm-svn: 173448

llvm-svn: 173433

llvm-svn: 173432

llvm-svn: 173431

This fixes DAG subtree analysis at the boundary.

llvm-svn: 173427

Maintain separate per-node and per-tree book-keeping.
Track all instructions above a DAG node including nested subtrees.
Seperately track instructions within a subtree.
Record subtree parents.

llvm-svn: 173426

Allow the strategy to select SchedDFS. Allow the results of SchedDFS
to affect initialization of the scheduler state.

llvm-svn: 173425

This is mostly refactoring, along with adding an instruction count
within the subtrees and ensuring we only look at data edges.

llvm-svn: 173420

interface and allow other strategies to select it.

llvm-svn: 173413

For sanity, create a root when NumDataSuccs >= 4. Splitting large
subtrees will no longer be detrimental after my next checkin to handle
nested tree. A magic number of 4 is fine because single subtrees
seldom rejoin more than this. It makes subtrees easier to visualize
and heuristics more sane.

llvm-svn: 173399

Patch by Stefan Hepp.

llvm-svn: 173395

llvm-svn: 173318

Allow schedulers to order DAG edges by critical path. This makes
DFS-based heuristics more stable and effective.

llvm-svn: 173317

The requirements of the strong heuristic are:

* A Protector is required for functions which contain an array, regardless of
  type or length.

* A Protector is required for functions which contain a structure/union which
  contains an array, regardless of type or length.  Note, there is no limit to
  the depth of nesting.

* A protector is required when the address of a local variable (i.e., stack
  based variable) is exposed. (E.g., such as through a local whose address is
  taken as part of the RHS of an assignment or a local whose address is taken as
  part of a function argument.)

llvm-svn: 173231

SSPStrong applies a heuristic to insert stack protectors in these situations:

* A Protector is required for functions which contain an array, regardless of
  type or length.

* A Protector is required for functions which contain a structure/union which
  contains an array, regardless of type or length.  Note, there is no limit to
  the depth of nesting.

* A protector is required when the address of a local variable (i.e., stack
  based variable) is exposed. (E.g., such as through a local whose address is
  taken as part of the RHS of an assignment or a local whose address is taken as
  part of a function argument.)

This patch implements the SSPString attribute to be equivalent to
SSPRequired. This will change in a subsequent patch.

llvm-svn: 173230

Previously we tried to infer it from the bit width size, with an added
IsIEEE argument for the PPC/IEEE 128-bit case, which had a default
value. This default value allowed bugs to creep in, where it was
inappropriate.

llvm-svn: 173138