[llvm-commits] [llvm] r48085 - in /llvm/trunk: include/llvm/BasicBlock.h lib/Transforms/Utils/BasicBlockUtils.cpp lib/VMCore/BasicBlock.cpp
Nick Lewycky
nicholas at mxc.ca
Sat Mar 8 21:04:48 PST 2008
Author: nicholas
Date: Sat Mar 8 23:04:48 2008
New Revision: 48085
URL: http://llvm.org/viewvc/llvm-project?rev=48085&view=rev
Log:
Two things. Preserve the unwind_to when splitting a BB.
Add the ability to remove just one instance of a BB from a phi node. This fixes
the compile error in the tree now.
Modified:
llvm/trunk/include/llvm/BasicBlock.h
llvm/trunk/lib/Transforms/Utils/BasicBlockUtils.cpp
llvm/trunk/lib/VMCore/BasicBlock.cpp
Modified: llvm/trunk/include/llvm/BasicBlock.h
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/include/llvm/BasicBlock.h?rev=48085&r1=48084&r2=48085&view=diff
==============================================================================
--- llvm/trunk/include/llvm/BasicBlock.h (original)
+++ llvm/trunk/include/llvm/BasicBlock.h Sat Mar 8 23:04:48 2008
@@ -185,7 +185,11 @@
/// DontDeleteUselessPHIs will keep PHIs that have one value or the same
/// value for all entries.
///
- void removePredecessor(BasicBlock *Pred, bool DontDeleteUselessPHIs = false);
+ /// OnlyDeleteOne will only remove one entry from a PHI, in case there were
+ /// duplicate entries for the Pred.
+ ///
+ void removePredecessor(BasicBlock *Pred, bool DontDeleteUselessPHIs = false,
+ bool OnlyDeleteOne = false);
/// splitBasicBlock - This splits a basic block into two at the specified
/// instruction. Note that all instructions BEFORE the specified iterator
Modified: llvm/trunk/lib/Transforms/Utils/BasicBlockUtils.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Transforms/Utils/BasicBlockUtils.cpp?rev=48085&r1=48084&r2=48085&view=diff
==============================================================================
--- llvm/trunk/lib/Transforms/Utils/BasicBlockUtils.cpp (original)
+++ llvm/trunk/lib/Transforms/Utils/BasicBlockUtils.cpp Sat Mar 8 23:04:48 2008
@@ -160,6 +160,7 @@
while (isa<PHINode>(SplitIt))
++SplitIt;
BasicBlock *New = Old->splitBasicBlock(SplitIt, Old->getName()+".split");
+ New->setUnwindDest(Old->getUnwindDest());
// The new block lives in whichever loop the old one did.
if (Loop *L = LI.getLoopFor(Old))
Modified: llvm/trunk/lib/VMCore/BasicBlock.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/VMCore/BasicBlock.cpp?rev=48085&r1=48084&r2=48085&view=diff
==============================================================================
--- llvm/trunk/lib/VMCore/BasicBlock.cpp (original)
+++ llvm/trunk/lib/VMCore/BasicBlock.cpp Sat Mar 8 23:04:48 2008
@@ -188,14 +188,12 @@
/// called while the predecessor still refers to this block.
///
void BasicBlock::removePredecessor(BasicBlock *Pred,
- bool DontDeleteUselessPHIs) {
+ bool DontDeleteUselessPHIs,
+ bool OnlyDeleteOne) {
assert((hasNUsesOrMore(16)||// Reduce cost of this assertion for complex CFGs.
find(pred_begin(this), pred_end(this), Pred) != pred_end(this)) &&
"removePredecessor: BB is not a predecessor!");
- if (Pred == getUnwindDest())
- setUnwindDest(NULL);
-
if (InstList.empty()) return;
PHINode *APN = dyn_cast<PHINode>(&front());
if (!APN) return; // Quick exit.
@@ -226,7 +224,11 @@
// Yup, loop through and nuke the PHI nodes
while (PHINode *PN = dyn_cast<PHINode>(&front())) {
// Remove the predecessor first.
- PN->removeIncomingValue(Pred, !DontDeleteUselessPHIs);
+ if (OnlyDeleteOne) {
+ int idx = PN->getBasicBlockIndex(Pred);
+ PN->removeIncomingValue(idx, !DontDeleteUselessPHIs);
+ } else
+ PN->removeIncomingValue(Pred, !DontDeleteUselessPHIs);
// If the PHI _HAD_ two uses, replace PHI node with its now *single* value
if (max_idx == 2) {
@@ -247,7 +249,12 @@
PHINode *PN;
for (iterator II = begin(); (PN = dyn_cast<PHINode>(II)); ) {
++II;
- PN->removeIncomingValue(Pred, false);
+ if (OnlyDeleteOne) {
+ int idx = PN->getBasicBlockIndex(Pred);
+ PN->removeIncomingValue(idx, false);
+ } else
+ PN->removeIncomingValue(Pred, false);
+
// If all incoming values to the Phi are the same, we can replace the Phi
// with that value.
Value* PNV = 0;
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