MachineBasicBlock::livein_iterator a const_iterator, because
clients shouldn't ever be using the iterator interface to
mutate the livein set.
llvm-svn: 101147
* Set the "DestA" and "DestB" according to how they're understood by the
method. I.e., if one or both of them should point to the "fall through" block,
then point to the fall through block.
* Improve the loop that removes superfluous edges to be more understandable.
llvm-svn: 100056
create symbols. It is extremely error prone and a source of a lot
of the remaining integrated assembler bugs on x86-64.
This fixes rdar://7807601.
llvm-svn: 99902
into TargetOpcodes.h. #include the new TargetOpcodes.h
into MachineInstr. Add new inline accessors (like isPHI())
to MachineInstr, and start using them throughout the
codebase.
llvm-svn: 95687
branches only to a landing pad. Without this check, the compiler would go into
an infinite loop because the branch to a landing pad is an "abnormal" edge which
wasn't being taken into account.
This is the meat of that fix:
if (!PrevBB.canFallThrough() && !MBB->BranchesToLandingPad(MBB)) {
The other stuff is simplification of the "branches to a landing pad" code.
llvm-svn: 91161
- Loosen the restrictions when checking of it branches to a landing pad.
- Make the loop more efficient by checking the '.insert' return value.
- Do cheaper checks first.
llvm-svn: 91101
more than one successor. Normally, these extra successors are dead. However,
some of them may branch to exception handling landing pads. If we remove those
successors, then the landing pads could go away if all predecessors to it are
removed. Before, it was checking if the direct successor was the landing
pad. But it could be the result of jumping through multiple basic blocks to get
to it. If we were to only check for the existence of an EH_LABEL in the basic
block and not remove successors if it's in there, then it could stop actually
dead basic blocks from being removed.
llvm-svn: 91092
running tail duplication when doing branch folding for if-conversion, and
we also want to be able to run tail duplication earlier to fix some
reg alloc problems. Move the CanFallThrough function from BranchFolding
to MachineBasicBlock so that it can be shared by TailDuplication.
llvm-svn: 89904
tail merging support to handle more cases.
- Recognize several cases where tail merging is beneficial even when
the tail size is smaller than the generic threshold.
- Make use of MachineInstrDesc::isBarrier to help detect
non-fallthrough blocks.
- Check for and avoid disrupting fall-through edges in more cases.
llvm-svn: 86871
- Be consistent when referring to MachineBasicBlocks: BB#0.
- Be consistent when referring to virtual registers: %reg1024.
- Be consistent when referring to unknown physical registers: %physreg10.
- Be consistent when referring to known physical registers: %RAX
- Be consistent when referring to register 0: %reg0
- Be consistent when printing alignments: align=16
- Print jump table contents.
- Don't print host addresses, in general.
- and various other cleanups.
llvm-svn: 85682
allow it to have multiple CFG edges to that block. This is needed
to allow MachineBasicBlock::isOnlyReachableByFallthrough to work
correctly. This fixes PR4126.
llvm-svn: 71018
entered via fall-through. Don't miss fallthroughs from blocks
terminated by conditional branches. Also, move
isOnlyReachableByFallthrough out of line.
llvm-svn: 68129
isImmediate(), isRegister(), and friends, to avoid confusion
about having two different names with the same meaning. I'm
not attached to the longer names, and would be ok with
changing to the shorter names if others prefer it.
llvm-svn: 56189