Add a getFirstNonPHI utility function.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@107778 91177308-0d34-0410-b5e6-96231b3b80d8
This commit is contained in:
Dan Gohman 2010-07-07 14:33:51 +00:00
parent b8c86a010c
commit d463a74464
2 changed files with 14 additions and 0 deletions

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@ -282,6 +282,13 @@ public:
/// branch to do so (e.g., a table jump). True is a conservative answer.
bool canFallThrough();
/// Returns a pointer to the first instructon in this block that is not a
/// PHINode instruction. When adding instruction to the beginning of the
/// basic block, they should be added before the returned value, not before
/// the first instruction, which might be PHI.
/// Returns end() is there's no non-PHI instruction.
iterator getFirstNonPHI();
/// getFirstTerminator - returns an iterator to the first terminator
/// instruction of this basic block. If a terminator does not exist,
/// it returns end()

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@ -139,6 +139,13 @@ void ilist_traits<MachineInstr>::deleteNode(MachineInstr* MI) {
Parent->getParent()->DeleteMachineInstr(MI);
}
MachineBasicBlock::iterator MachineBasicBlock::getFirstNonPHI() {
iterator I = begin();
while (I != end() && I->isPHI())
++I;
return I;
}
MachineBasicBlock::iterator MachineBasicBlock::getFirstTerminator() {
iterator I = end();
while (I != begin() && (--I)->getDesc().isTerminator())