in addition to integer expressions. Rewrite GetOrEnforceKnownAlignment
as a ComputeMaskedBits problem, moving all of its special alignment
knowledge to ComputeMaskedBits as low-zero-bits knowledge.

Also, teach ComputeMaskedBits a few basic things about Mul and PHI
instructions.

This improves ComputeMaskedBits-based simplifications in a few cases,
but more noticeably it significantly improves instcombine's alignment
detection for loads, stores, and memory intrinsics.

llvm-svn: 49492

llvm-svn: 49430

GVN and into its own pass.

llvm-svn: 49419

llvm-svn: 49418

in both time and memory savings for GVN.  For example, one testcase went from 10.5s to 6s with
this patch.

llvm-svn: 49345

allocations, which GVN can't optimize anyways.

llvm-svn: 49329

llvm-svn: 49283

Specifically, introduction of XXX::Create methods
for Users that have a potentially variable number of
Uses.

llvm-svn: 49277

Iterators folloring a SmallVector erased element are invalidated so
don't access cached iterators from after the erased element.

Re-apply 49056 with SmallVector support.

llvm-svn: 49106

llvm-svn: 49060

Iterators folloring a SmallVector erased element are invalidated so
don't access cached iterators from after the erased element.

llvm-svn: 49056

llvm-svn: 48971

patch by David Chisnall.

llvm-svn: 48963

when something changes, instead of moving forward.  This allows us to 
simplify memset lowering, inserting the memset at the end of the range of 
stuff we're touching instead of at the start.

This, in turn, allows us to make use of the addressing instructions already
used in the function instead of inserting our own.  For example, we now
codegen:

	%tmp41 = getelementptr [8 x i8]* %ref_idx, i32 0, i32 0		; <i8*> [#uses=2]
	call void @llvm.memset.i64( i8* %tmp41, i8 -1, i64 8, i32 1 )

instead of:

	%tmp20 = getelementptr [8 x i8]* %ref_idx, i32 0, i32 7		; <i8*> [#uses=1]
	%ptroffset = getelementptr i8* %tmp20, i64 -7		; <i8*> [#uses=1]
	call void @llvm.memset.i64( i8* %ptroffset, i8 -1, i64 8, i32 1 )

llvm-svn: 48940

into a memset!) faster by avoiding an allocation of an std::list node.

llvm-svn: 48939

llvm-svn: 48937

memsets that initialize "structs of arrays" and other store sequences
that are not sequential.  This is still only enabled if you pass 
-form-memset-from-stores.  The flag is not heavily tested and I haven't
analyzed the perf regressions when -form-memset-from-stores is passed
either, but this causes no make check regressions.

llvm-svn: 48909

Increment iterator in advance.

llvm-svn: 48890

Handle a special case xor undef, undef -> 0. Technically this should be transformed to undef. But this is such a common idiom (misuse) we are going to handle it.

llvm-svn: 48791

llvm-svn: 48738

llvm-svn: 48720

Transform (zext (or (icmp), (icmp))) to (or (zext (cimp), (zext icmp))) if at least one of the (zext icmp) can be transformed to eliminate an icmp.

llvm-svn: 48715

This fires dozens of times across spec and multisource, but I don't know
if it actually speeds stuff up.  Hopefully the testers will show something
nice :)

llvm-svn: 48680

llvm-svn: 48679

merging optimization.  Nothing to see here, hopefully more later :)

llvm-svn: 48670

adding <map> to many files that actually do need it.

llvm-svn: 48667

llvm-svn: 48662

each basic block.

llvm-svn: 48660

llvm-svn: 48658

from their aggregate operands by moving the getresult
instructions.

llvm-svn: 48657

llvm-svn: 48639

simplify things like (X & 4) >> 1 == 2  --> (X & 4) == 4.

since it is obvious that the shift doesn't remove any bits.

llvm-svn: 48631

Patch by Erick Tryzelaar.

llvm-svn: 48602

llvm-svn: 48567

llvm-svn: 48556

llvm-svn: 48474

Patch originally by Erick Tryzelaar, but has been modified somewhat.

llvm-svn: 48419

the type instead of the byte size. This was causing troublesome mis-compilations.

True to form, this took 2 days to find and is a one-line fix. :-P

llvm-svn: 48354

pointer bitcast when performing return slot optimization.

llvm-svn: 48343

1. There is now a "PAListPtr" class, which is a smart pointer around
   the underlying uniqued parameter attribute list object, and manages
   its refcount.  It is now impossible to mess up the refcount.
2. PAListPtr is now the main interface to the underlying object, and
   the underlying object is now completely opaque.
3. Implementation details like SmallVector and FoldingSet are now no
   longer part of the interface.
4. You can create a PAListPtr with an arbitrary sequence of
   ParamAttrsWithIndex's, no need to make a SmallVector of a specific 
   size (you can just use an array or scalar or vector if you wish).
5. All the client code that had to check for a null pointer before
   dereferencing the pointer is simplified to just access the 
   PAListPtr directly.
6. The interfaces for adding attrs to a list and removing them is a
   bit simpler.

Phase #2 will rename some stuff (e.g. PAListPtr) and do other less 
invasive changes.

llvm-svn: 48289