Retry commit r200022 with a fix for the build bot errors. Constant expressions
have (unlike instructions) module scope use lists and therefore may have users
in different functions. The fix is to simply ignore these out-of-function uses.

llvm-svn: 200034

DAGCombiner::GatherAllAliases, which is only used when AA used is enabled
during DAGCombine, had a fundamentally incorrect assumption for which this
change compensates. GatherAllAliases, which is used to find aliasing
predecessor chain nodes (so that a better chain can be selected for a load or
store to enable subsequent optimizations) assumed that walking up the chain
would always catch all possibly-aliasing loads and stores. This is not true: To
really find all aliases, we also need to search for aliases through the value
operand of a store, etc.  Consider the following situation:

  Token1 = ...
  L1 = load Token1, %52
  S1 = store Token1, L1, %51
  L2 = load Token1, %52+8
  S2 = store Token1, L2, %51+8
  Token2 = Token(S1, S2)
  L3 = load Token2, %53
  S3 = store Token2, L3, %52
  L4 = load Token2, %53+8
  S4 = store Token2, L4, %52+8

If we search for aliases of S3 (which loads address %52), and we look only
through the chain, then we'll miss the trivial dependence on L1 (which loads
from %52). We then might change all loads and stores to use Token1 as their
chain operand, which could result in copying %53 into %52 before copying
%52 into %51 (which should happen first).

The problem is, however, that searching for such data dependencies can become
expensive, and the cost is not directly related to the chain depth. Instead,
we'll rule out such configurations by insisting that we've visited all chain
users (except for users of the original chain, which is not necessary).  When
doing this, we need to look through nodes we don't care about (otherwise,
things like register copies will interfere with trivial use cases).

Unfortunately, I don't have a small test case for this problem. Creating the
underlying situation is not hard (a pair of memcpys will do it), but arranging
for the default instruction schedule to be incorrect is very fragile.

This unbreaks self hosting on PPC64 when using
-mllvm -combiner-global-alias-analysis -mllvm -combiner-alias-analysis.

llvm-svn: 200033

We don't want to lose attributes when a function decl without them is merged
with a function decl that has them.
PR2382

llvm-svn: 200030

PR18600.

llvm-svn: 200028

<rdar://problem/15611947>

llvm-svn: 200027

This reverts commit r200022 to unbreak the build bots.

llvm-svn: 200024

These transformations obviously won't work for indexed (pre/post-inc) loads and
stores. In practice, I'm not sure there is any benefit to enabling them for
indexed nodes because other transformations that these might enable likely also
won't handle indexed nodes.

I don't have an in-tree test case that hits this problem, but an upcoming bug
fix will make it much more likely.

llvm-svn: 200023

This pass identifies expensive constants to hoist and coalesces them to
better prepare it for SelectionDAG-based code generation. This works around the
limitations of the basic-block-at-a-time approach.

First it scans all instructions for integer constants and calculates its
cost. If the constant can be folded into the instruction (the cost is
TCC_Free) or the cost is just a simple operation (TCC_BASIC), then we don't
consider it expensive and leave it alone. This is the default behavior and
the default implementation of getIntImmCost will always return TCC_Free.

If the cost is more than TCC_BASIC, then the integer constant can't be folded
into the instruction and it might be beneficial to hoist the constant.
Similar constants are coalesced to reduce register pressure and
materialization code.

When a constant is hoisted, it is also hidden behind a bitcast to force it to
be live-out of the basic block. Otherwise the constant would be just
duplicated and each basic block would have its own copy in the SelectionDAG.
The SelectionDAG recognizes such constants as opaque and doesn't perform
certain transformations on them, which would create a new expensive constant.

This optimization is only applied to integer constants in instructions and
simple (this means not nested) constant cast experessions. For example:
%0 = load i64* inttoptr (i64 big_constant to i64*)

Reviewed by Eric

llvm-svn: 200022

llvm-svn: 200021

llvm-svn: 200020

Sweep the codebase for common typos. Includes some changes to visible function
names that were misspelt.

llvm-svn: 200018

This enables IO error reports in both the child and server processes.

The scheme still isn't entirely satisfactory and output is jumbled but it beats
having no output at all. This will hopefully unblock ARM support (PR18057).

llvm-svn: 200017

llvm-svn: 200016

llvm-svn: 200014

r200011 remove the special codepaths in MC for inline asm, so we can now test
all the logic with just llc + llvm-mc.

llvm-svn: 200013

There is no inline asm in a .s file. Therefore, there should be no logic to
handle it in the streamer. Inline asm only exists in bitcode files, so the
logic can live in the (long misnamed) AsmPrinter class.

llvm-svn: 200011

llvm-svn: 200000

llvm-svn: 199995

in order to fix the cygwin/mingw bots.

This reverts commit r199990.

llvm-svn: 199991

compile unit. Make these relocations on the platforms that need
relocations and add a routine to ensure that we don't put the
addresses in an offset table for split dwarf.

llvm-svn: 199990

llvm-svn: 199978

With this change, all supported tests in test/ExecutionEngine pass in sparcv9.

llvm-svn: 199977

This commit teaches the X86 backend to create the same X86 instructions when it
lowers an sadd/ssub with overflow intrinsic and a conditional branch that uses
that overflow result. This allows SelectionDAG to recognize and remove one of
the redundant operations.

This fixes <rdar://problem/15874016> and <rdar://problem/15661073>.

Reviewed by Nadav

llvm-svn: 199976

These all use the compare-and-swap CASA/CASXA instructions.

llvm-svn: 199975

Add test cases to check parsing of v9 double registers and their aliased quad registers.

llvm-svn: 199974

llvm-svn: 199972

llvm-svn: 199971

llvm-svn: 199969

llvm-svn: 199968

llvm-svn: 199967

We completely skipped promotion in LICM if the loop has a preheader or
dedicated exits, but not *both*. We hoist if there is a preheader, and
sink if there are dedicated exits, but either hoisting or sinking can
move loop invariant code out of the loop!

I have no idea if this has a practical consequence. If anyone has ideas
for a test case, let me know.

llvm-svn: 199966

llvm-svn: 199965

literal that bakes a pass name and forces parsing it in the pass
manager.

llvm-svn: 199963

llvm-svn: 199955

the existence of comdat/special sections.

llvm-svn: 199954

llvm-svn: 199951

registers in memory addresses that do not match the index register. As it does
for .att_syntax.

rdar://15887380

llvm-svn: 199948

The client and server now use a single unified low-level RPC core built around
LLVM's existing cross-platform abstractions.

llvm-svn: 199947

scale factors in memory addresses. As it does for .att_syntax.

It was producing:
Assertion failed: (((Scale == 1 || Scale == 2 || Scale == 4 || Scale == 8)) && "Invalid scale!"), function CreateMem, file /Volumes/SandBox/llvm/lib/Target/X86/AsmParser/X86AsmParser.cpp, line 1133.

rdar://14967214

llvm-svn: 199942

code this looks correct, but could use review. The previous
was definitely not correct.

llvm-svn: 199940