llvm-svn: 133499

Change PHINodes to store simple pointers to their incoming basic blocks,
instead of full-blown Uses.

Note that this loses an optimization in SplitCriticalEdge(), because we
can no longer walk the use list of a BasicBlock to find phi nodes. See
the comment I removed starting "However, the foreach loop is slow for
blocks with lots of predecessors".

Extend replaceAllUsesWith() on a BasicBlock to also update any phi
nodes in the block's successors. This mimics what would have happened
when PHINodes were proper Users of their incoming blocks. (Note that
this only works if OldBB->replaceAllUsesWith(NewBB) is called when
OldBB still has a terminator instruction, so it still has some
successors.)

llvm-svn: 133435

In cases such as the attached test, where the case value for a switch
destination is used in a phi node that follows the destination, it
might be better to replace that value with the condition value of the
switch, so that more blocks can be folded away with
TryToSimplifyUncondBranchFromEmptyBlock because there are less
conflicts in the phi node.

llvm-svn: 133344

llvm-svn: 133298

llvm-svn: 133251

llvm-svn: 133086

llvm-svn: 133085

llvm-svn: 133078

line info correctly.

llvm-svn: 132961

llvm-svn: 132954

intrinsics. In fact, we'll optimize a bitcast to that when possible. Detect it
when looking for the lifetime intrinsics.

No test case, noticed by inspection.

llvm-svn: 132906

pad, separating the exception and selector calls from the new lpad.  Teaching
it not to do that, or to properly adjust the CFG afterwards, is out of
scope because it would require the other edges to the landing pad to be split
as well (effectively).  Instead, just recover from the most likely cases
during inlining.  The best long-term solution is to change the exception
representation and commit to either requiring or not requiring the more
complex edge-splitting logic;  this is just a shorter-term hack.

llvm-svn: 132799

llvm-svn: 132797

then we don't want to set the destination in the indirect branch to the
destination. This is because the indirect branch needs its destinations to have
had their block addresses taken. This isn't so of the new critical edge that's
split during this process. If it turns out that the destination block has only
one predecessor, and that being a BB with an indirect branch, then it won't be
marked as 'used' and may be removed.
PR10072

llvm-svn: 132638

landing pad, forward llvm.eh.resume calls to it instead of turning them
invalidly into invokes.

llvm-svn: 132382

fixes self-host.

llvm-svn: 132275

transformed by the inliner into a branch to the enclosing landing pad
(when inlined through an invoke).  If not so optimized, it is lowered
DWARF EH preparation into a call to _Unwind_Resume (or _Unwind_SjLj_Resume
as appropriate).  Its chief advantage is that it takes both the
exception value and the selector value as arguments, meaning that there
is zero effort in recovering these;  however, the frontend is required
to pass these down, which is not actually particularly difficult.

Also document the behavior of landing pads a bit better, and make it
clearer that it's okay that personality functions don't always land at
landing pads.  This is just a fact of life.  Don't write optimizations that
rely on pushing things over an unwind edge.

llvm-svn: 132253

  - the selector for the landing pad must provide all available information
    about the handlers, filters, and cleanups within that landing pad
  - calls to _Unwind_Resume must be converted to branches to the enclosing
    lpad so as to avoid re-entering the unwinder when the lpad claimed it
    was going to handle the exception in some way
This is quite specific to libUnwind-based unwinding.  In an effort to not
interfere too badly with other unwinders, and with existing hacks in frontends,
this only triggers on _Unwind_Resume (not _Unwind_Resume_or_Rethrow) and does
nothing with selectors if it cannot find a selector call for either lpad.

llvm-svn: 132200

One more debug line number miss in instcombine (although the code in question isn't actually in instcombine).

llvm-svn: 132170

llvm-svn: 131956

promoting allocas to SSA variables. Fixes <rdar://problem/9479036>.

llvm-svn: 131953

Add a parameter to ConstantFoldTerminator() that callers can use to ask it to also clean up the condition of any conditional terminator it folds to be unconditional, if that turns the condition into dead code. This just means it calls RecursivelyDeleteTriviallyDeadInstructions() in strategic spots. It defaults to the old behavior.

I also changed -simplifycfg, -jump-threading and -codegenprepare to use this to produce slightly better code without any extra cleanup passes (AFAICT this was the only place in -simplifycfg where now-dead conditions of replaced terminators weren't being cleaned up). The only other user of this function is -sccp, but I didn't read that thoroughly enough to figure out whether it might be holding pointers to instructions that could be deleted by this.

llvm-svn: 131855

of the inlinee to the code representing the original function.

llvm-svn: 131838

Reapply r131605. This time with a fix, which is to use NoFolder.

llvm-svn: 131673

llvm-svn: 131620

llvm-svn: 131609

llvm-svn: 131607

llvm-svn: 131605

llvm-svn: 131598

llvm-svn: 131580

llvm-svn: 131571

llvm-svn: 131566

llvm-svn: 131561

llvm-svn: 131552

llvm-svn: 131551

llvm-svn: 131548

llvm-svn: 131545

llvm-svn: 131543

llvm-svn: 131541

llvm-svn: 131508