argpromotion and structretpromote.  Basically, when replacing
a function, they used the 'changeFunction' api which changes
the entry in the function map (and steals/reuses the callgraph
node).

This has some interesting effects: first, the problem is that it doesn't
update the "callee" edges in any callees of the function in the call graph.
Second, this covers for a major problem in all the CGSCC pass stuff, which 
is that it is completely broken when functions are deleted if they *don't*
reuse a CGN.  (there is a cute little fixme about this though :).

This patch changes the protocol that CGSCC passes must obey: now the CGSCC 
pass manager copies the SCC and preincrements its iterator to avoid passes
invalidating it.  This allows CGSCC passes to mutate the current SCC.  However
multiple passes may be run on that SCC, so if passes do this, they are now
required to *update* the SCC to be current when they return.

Other less interesting parts of this patch are that it makes passes update
the CG more directly, eliminates changeFunction, and requires clients of
replaceCallSite to specify the new callee CGN if they are changing it.

llvm-svn: 80527

llvm-svn: 80524

llvm-svn: 80515

is itself a bitcast.  Since we have gep(bitcast(bitcast(y))) in this
case, just wait for the two bitcasts to get zapped.  This prevents
instcombine from confusing some aliasing stuff, and allows it to
directly eliminate the load in the testcase.

llvm-svn: 80508

llvm-svn: 80507

in a few scalar xforms to simplify things.

llvm-svn: 80506

llvm-svn: 80505

llvm-svn: 80504

llvm-svn: 80502

the new Instcombine builder.

llvm-svn: 80501

llvm-svn: 80500

Remove the assertion and generalize the code for ARM NEON stuff.

llvm-svn: 80498

implementation.

llvm-svn: 80493

workslist and is set to insert new instructions before the current one.
Convert a bunch of stuff that used to call InsertNewInstBefore over to
use it, greatly simplifying code and making it more natural.

There is still a lot more to go, but this is a good start.

llvm-svn: 80492

if the operand is not an instruction.

Simplify most uses of AddOperandsToWorkList to use AddValue and
inline it into the one remaining callsite.

llvm-svn: 80488

argument stronger typed.

llvm-svn: 80487

former looks too much like AddUsersToWorkList and keeps
confusing me.

Remove AddSoonDeadInstToWorklist and change its two callers
to do the same thing in a simpler way.

llvm-svn: 80486

llvm-svn: 80485

- Switch Emit{CommonSymbol,Zerofill} to take alignment in bytes (for consistency).

llvm-svn: 80484

into their callers.  simplify ReplaceInstUsesWith.  Make
EraseInstFromFunction only add operands to the worklist if
there aren't too many of them (this was a scalability win
for crazy programs that was only infrequently enforced).
Switch more code to using EraseInstFromFunction instead of
duplicating it inline.  Change some fcmp/icmp optimizations
to modify fcmp/icmp in place instead of creating a new one
and deleting the old one just to change the predicate.

llvm-svn: 80483

llvm-svn: 80482

llvm-svn: 80481

other places.

llvm-svn: 80478

llvm-svn: 80477

llvm-svn: 80476

does constant folding of gep's: this is already handled in
a more general way.

No functionality change.

llvm-svn: 80475

to see what queries are being made by a transformation, we might as well
default to printing them.

llvm-svn: 80474

llvm-svn: 80466

llvm-svn: 80454

llvm-svn: 80453

llvm-svn: 80452

llvm-svn: 80451

llvm-svn: 80450

a register to 0. This fixes PR4814.

llvm-svn: 80445

llvm-svn: 80431

llvm-svn: 80429

  encodings.
- Make some of the values emitted by the FDEs dependent upon the pointer
  size. This is in line with how GCC does things. And it has the benefit of
  working for Darwin in 64-bit mode now.

llvm-svn: 80428

doesn't handle all values of the formatting. Those can be added as needed.

llvm-svn: 80427

and make the reference pointer size as it should be.

Fixes an abort on a testcase derived from libunwind's personality
test in 64-bit.

llvm-svn: 80414

GlobalVariables to MDNodes.

llvm-svn: 80411