it to get better phi node simplification.

llvm-svn: 119055

"%z = %x and %y".  If GVN can prove that %y equals %x, then it turns
this into "%z = %x and %x".  With the new code, %z will be replaced
with %x everywhere (and then deleted).  Previously %z would be value
numbered too, which is a waste of time.  Also, while a clever value
numbering algorithm would give %z the same value number as %x, our
current one doesn't do so (at least I don't think it does).  The new
logic has an essentially equivalent effect to what you would get if
%z was given the same value number as %x, i.e. it should make value
numbering smarter.  While there, get hold of target data once at the
start rather than a gazillion times all over the place.

llvm-svn: 118923

one store dead. This is especially noticeable in
SingleSource/Benchmarks/Shootout/objinst.

llvm-svn: 118875

and vaarg instructions.

llvm-svn: 118845

llvm-svn: 118788

execute. Make Sink's predicate more precise.

llvm-svn: 118787

references. For example, this allows gvn to eliminate the load in
this example:

  void foo(int n, int* p, int *q) {
    p[0] = 0;
    p[1] = 1;
    if (n) {
      *q = p[0];
    }
  }

llvm-svn: 118714

instructions instead of hard-coding operand numbers.

llvm-svn: 118698

llvm-svn: 118618

Give up on doing in-line instruction simplification during correlated value propagation.  Instruction simplification
needs to be guaranteed never to be run on an unreachable block.  However, earlier block simplifications may have
changed the CFG to make block that were reachable when we began our iteration unreachable by the time we try to
simplify them. (Note that this also means that our depth-first iterators were potentially being invalidated).

This should not have a large impact on code quality, since later runs of instcombine should pick up these simplifications.
Fixes PR8506.

llvm-svn: 117709

Inline asm multiple alternative constraints development phase 2 - improved basic logic, added initial platform support.

llvm-svn: 117667

uint64_t, plus fixes for places I missed before.

llvm-svn: 116875

llvm-svn: 116858

they do not also require them.  This allows us to reduce inter-pass linkage
dependencies.

llvm-svn: 116854

use uint64_t.

llvm-svn: 116839

Get rid of static constructors for pass registration.  Instead, every pass exposes an initializeMyPassFunction(), which
must be called in the pass's constructor.  This function uses static dependency declarations to recursively initialize
the pass's dependencies.

Clients that only create passes through the createFooPass() APIs will require no changes.  Clients that want to use the
CommandLine options for passes will need to manually call the appropriate initialization functions in PassInitialization.h
before parsing commandline arguments.

I have tested this with all standard configurations of clang and llvm-gcc on Darwin.  It is possible that there are problems
with the static dependencies that will only be visible with non-standard options.  If you encounter any crash in pass
registration/creation, please send the testcase to me directly.

llvm-svn: 116820

llvm-svn: 116815

llvm-svn: 116743

llvm-svn: 116670

forwarding is implemented with a load/store pair rather than a memcpy.

llvm-svn: 116637

llvm-svn: 116387

perform initialization without static constructors AND without explicit initialization
by the client.  For the moment, passes are required to initialize both their
(potential) dependencies and any passes they preserve.  I hope to be able to relax
the latter requirement in the future.

llvm-svn: 116334

formulae which become illegal as a result of the offset updating don't
escape.

This is for rdar://8529692. No testcase yet, because the given cases
hit use-list ordering differences.

llvm-svn: 116093

llvm-svn: 116034

one user. This code will be restructured soon and FormulaSorter
is getting in the way.

llvm-svn: 116012

llvm-svn: 116011

not just base registers.

llvm-svn: 116010

llvm-svn: 116009

the old use to the new one.

llvm-svn: 116008

This doesn't usually matter, because the other heuristics usually
succeed regardless, but it's good to keep the register use
bookkeeping consistent.

llvm-svn: 116005

llvm-svn: 116004

llvm-svn: 115996

initialization functions that initialize the set of passes implemented in
that library.  Add C bindings for these functions as well.

llvm-svn: 115927

Now that the profitable bits of EnableFullLoadPRE have been enabled by default, rip out the remainder.
Anyone interested in more general PRE would be better served by implementing it separately, to get real
anticipation calculation, etc.

llvm-svn: 115337

memcpy alignment is the minimum of the incoming alignments.

Fixes PR 8266.

llvm-svn: 115305

The x86_mmx type is used for MMX intrinsics, parameters and
return values where these use MMX registers, and is also
supported in load, store, and bitcast.

Only the above operations generate MMX instructions, and optimizations
do not operate on or produce MMX intrinsics. 

MMX-sized vectors <2 x i32> etc. are lowered to XMM or split into
smaller pieces.  Optimizations may occur on these forms and the
result casted back to x86_mmx, provided the result feeds into a
previous existing x86_mmx operation.

The point of all this is prevent optimizations from introducing
MMX operations, which is unsafe due to the EMMS problem.

llvm-svn: 115243

We do want to allow LoadPRE to perform LICM-like transformations: we already consider PHI nodes to be negligible for
code size (making this transform code size neutral), and it allows us to hoist values out of loops, which is always
a good thing.

llvm-svn: 115205

The bug that broke i386 linux has been fixed in r115191.

llvm-svn: 115204

Tighten up prototype verification of strchr and strrchr to avoid a crash in the very unlikely case that someone passes an integer > i64 to strchr.

llvm-svn: 115144

llvm-svn: 115116