llvm-svn: 119753

Fix bug in DAGCombiner for ARM that was trying to do a ShiftCombine on illegal types (vector should be split first).
Added test case.

llvm-svn: 119749

should delete what when the object gets copied around. It's also making valgrind
upset.

llvm-svn: 119747

llvm-svn: 119744

llvm-svn: 119743

llvm-svn: 119740

not anyext(select).  Spotted by Frits van Bommel.

llvm-svn: 119739

This function was being called from two different places for completely
unrelated reasons.  During type legalization, it was called to expand 64-bit
shift operations.  During operation legalization, it was called to handle
Neon vector shifts.  The vector shift code was not written to check for
illegal types, since it was assumed to be only called after type legalization.
Fixed this by splitting off the 64-bit shift expansion into a separate
function.  I don't have a particular testcase for this; I just noticed it
by inspection.

llvm-svn: 119738

llvm-svn: 119737

llvm-svn: 119733

if the extension types were not the same.  The result was that if you
fed a select with sext and zext loads, as in the testcase, then it
would get turned into a zext (or sext) of the select, which is wrong
in the cases when it should have been an sext (resp. zext).  Reported
and diagnosed by Sebastien Deldon.

llvm-svn: 119728

preserves LCSSA form out of ScalarEvolution and into the LoopInfo
class.  Use it to check that SimplifyInstruction simplifications
are not breaking LCSSA form.  Fixes PR8622.

llvm-svn: 119727

llvm-svn: 119726

Remove movePastCSLoadStoreOps and associated code for simple pointer
increments. Update routines that depended upon other opcodes for save/restore.

Adjust all testcases accordingly.

llvm-svn: 119725

LLVMContext, causing memory errors.  Patch by Peter Collingbourne.

llvm-svn: 119721

Use thread-safe statics to avoid a static constructor here.  This isn't thread-safe on MSVC, but we don't
support threaded LLVM there anyways.

llvm-svn: 119718

llvm-svn: 119717

llvm-svn: 119716

Completely rework the datastructure GVN uses to represent the value number to leader mapping.  Previously,
this was a tree of hashtables, and a query recursed into the table for the immediate dominator ad infinitum
if the initial lookup failed.  This led to really bad performance on tall, narrow CFGs.

We can instead replace it with what is conceptually a multimap of value numbers to leaders (actually
represented by a hashtable with a list of Value*'s as the value type), and then
determine which leader from that set to use very cheaply thanks to the DFS numberings maintained by
DominatorTree.  Because there are typically few duplicates of a given value, this scan tends to be
quite fast.  Additionally, we use a custom linked list and BumpPtr allocation to avoid any unnecessary
allocation in representing the value-side of the multimap.

This change brings with it a 15% (!) improvement in the total running time of GVN on 403.gcc, which I
think is pretty good considering that includes all the "real work" being done by MemDep as well.

The one downside to this approach is that we can no longer use GVN to perform simple conditional progation,
but that seems like an acceptable loss since we now have LVI and CorrelatedValuePropagation to pick up
the slack.  If you see conditional propagation that's not happening, please file bugs against LVI or CVP.

llvm-svn: 119714

instruction. Any that may be expanded otherwise by MC lowering should
override this value. rdar://8683274

llvm-svn: 119713

llvm-svn: 119712

llvm-svn: 119708

simple form of INITIALIZE_PASS.

llvm-svn: 119707

llvm-svn: 119706

llvm-svn: 119705

enabling more PRE. PR8586.

llvm-svn: 119704

saying "it would be bad", give an example of what is going on.

llvm-svn: 119695

refusing to optimize two memcpy's like this:

copy A <- B
copy C <- A

if it couldn't prove that noalias(B,C).  We can eliminate
the copy by producing a memmove instead of memcpy.

llvm-svn: 119694

source and dest are known to not overlap.

llvm-svn: 119692

there is no need to check to see if the source and dest of a memcpy are noalias,
behavior is undefined if not.

llvm-svn: 119691

llvm-svn: 119690

out of processMemCpy into its own function.

llvm-svn: 119687

if it is passed as a byval argument.  The byval argument will just be a
read, so it is safe to read from the original global instead.  This allows
us to promote away the %agg.tmp alloca in PR8582

llvm-svn: 119686

to ignore calls that obviously can't modify the alloca
because they are readonly/readnone.

llvm-svn: 119683

optimization.  If the alloca that is "memcpy'd from constant" also has
a memcpy from *it*, ignore it: it is a load.  We now optimize the testcase to:

define void @test2() {
  %B = alloca %T
  %a = bitcast %T* @G to i8*
  %b = bitcast %T* %B to i8*
  call void @llvm.memcpy.p0i8.p0i8.i64(i8* %b, i8* %a, i64 124, i32 4, i1 false)
  call void @bar(i8* %b)
  ret void
}

previously we would generate:

define void @test() {
  %B = alloca %T
  %b = bitcast %T* %B to i8*
  %G.0 = getelementptr inbounds %T* @G, i32 0, i32 0
  %tmp3 = load i8* %G.0, align 4
  %G.1 = getelementptr inbounds %T* @G, i32 0, i32 1
  %G.15 = bitcast [123 x i8]* %G.1 to i8*
  %1 = bitcast [123 x i8]* %G.1 to i984*
  %srcval = load i984* %1, align 1
  %B.0 = getelementptr inbounds %T* %B, i32 0, i32 0
  store i8 %tmp3, i8* %B.0, align 4
  %B.1 = getelementptr inbounds %T* %B, i32 0, i32 1
  %B.12 = bitcast [123 x i8]* %B.1 to i8*
  %2 = bitcast [123 x i8]* %B.1 to i984*
  store i984 %srcval, i984* %2, align 1
  call void @bar(i8* %b)
  ret void
}

llvm-svn: 119682

  sahf	movl	344(%rdi),%r14d
we used to produce:

t.s:2:1: error: unexpected token in argument list

^

we now produce:
t.s:1:11: error: unexpected token in argument list
sahf	movl	344(%rdi),%r14d
    	    	^

rdar://8581401

llvm-svn: 119676

and testing is easier.  A good example is the unknown-location.ll test that
now can just look for ".loc 1 0 0".  We also don't use a DW_LNE_set_address for
every address change anymore.

llvm-svn: 119613

llvm-svn: 119610

llvm-svn: 119608

the operand to the pattern.

llvm-svn: 119607