Move sparc-specific livevar code into lib/Target/Sparc
llvm-svn: 10733
diff --git a/llvm/lib/Target/Sparc/LiveVar/BBLiveVar.cpp b/llvm/lib/Target/Sparc/LiveVar/BBLiveVar.cpp
new file mode 100644
index 0000000..f54b42a
--- /dev/null
+++ b/llvm/lib/Target/Sparc/LiveVar/BBLiveVar.cpp
@@ -0,0 +1,230 @@
+//===-- BBLiveVar.cpp - Live Variable Analysis for a BasicBlock -----------===//
+//
+// The LLVM Compiler Infrastructure
+//
+// This file was developed by the LLVM research group and is distributed under
+// the University of Illinois Open Source License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+// This is a wrapper class for BasicBlock which is used by live var analysis.
+//
+//===----------------------------------------------------------------------===//
+
+#include "BBLiveVar.h"
+#include "llvm/CodeGen/FunctionLiveVarInfo.h"
+#include "llvm/CodeGen/MachineInstr.h"
+#include "llvm/CodeGen/MachineBasicBlock.h"
+#include "llvm/Support/CFG.h"
+#include "Support/SetOperations.h"
+#include "../SparcInternals.h"
+
+namespace llvm {
+
+BBLiveVar::BBLiveVar(const BasicBlock &bb, MachineBasicBlock &mbb, unsigned id)
+ : BB(bb), MBB(mbb), POID(id) {
+ InSetChanged = OutSetChanged = false;
+
+ calcDefUseSets();
+}
+
+//-----------------------------------------------------------------------------
+// calculates def and use sets for each BB
+// There are two passes over operands of a machine instruction. This is
+// because, we can have instructions like V = V + 1, since we no longer
+// assume single definition.
+//-----------------------------------------------------------------------------
+
+void BBLiveVar::calcDefUseSets() {
+ // iterate over all the machine instructions in BB
+ for (MachineBasicBlock::const_reverse_iterator MII = MBB.rbegin(),
+ MIE = MBB.rend(); MII != MIE; ++MII) {
+ const MachineInstr *MI = *MII;
+
+ if (DEBUG_LV >= LV_DEBUG_Verbose) {
+ std::cerr << " *Iterating over machine instr ";
+ MI->dump();
+ std::cerr << "\n";
+ }
+
+ // iterate over MI operands to find defs
+ for (MachineInstr::const_val_op_iterator OpI = MI->begin(), OpE = MI->end();
+ OpI != OpE; ++OpI)
+ if (OpI.isDef()) // add to Defs if this operand is a def
+ addDef(*OpI);
+
+ // do for implicit operands as well
+ for (unsigned i = 0; i < MI->getNumImplicitRefs(); ++i)
+ if (MI->getImplicitOp(i).isDef())
+ addDef(MI->getImplicitRef(i));
+
+ // iterate over MI operands to find uses
+ for (MachineInstr::const_val_op_iterator OpI = MI->begin(), OpE = MI->end();
+ OpI != OpE; ++OpI) {
+ const Value *Op = *OpI;
+
+ if (isa<BasicBlock>(Op))
+ continue; // don't process labels
+
+ if (OpI.isUse()) { // add to Uses only if this operand is a use
+ //
+ // *** WARNING: The following code for handling dummy PHI machine
+ // instructions is untested. The previous code was broken and I
+ // fixed it, but it turned out to be unused as long as Phi
+ // elimination is performed during instruction selection.
+ //
+ // Put Phi operands in UseSet for the incoming edge, not node.
+ // They must not "hide" later defs, and must be handled specially
+ // during set propagation over the CFG.
+ if (MI->getOpCode() == V9::PHI) { // for a phi node
+ const Value *ArgVal = Op;
+ const BasicBlock *PredBB = cast<BasicBlock>(*++OpI); // next ptr is BB
+
+ PredToEdgeInSetMap[PredBB].insert(ArgVal);
+
+ if (DEBUG_LV >= LV_DEBUG_Verbose)
+ std::cerr << " - phi operand " << RAV(ArgVal) << " came from BB "
+ << RAV(PredBB) << "\n";
+ } // if( IsPhi )
+ else {
+ // It is not a Phi use: add to regular use set and remove later defs.
+ addUse(Op);
+ }
+ } // if a use
+ } // for all operands
+
+ // do for implicit operands as well
+ for (unsigned i = 0; i < MI->getNumImplicitRefs(); ++i) {
+ assert(MI->getOpCode() != V9::PHI && "Phi cannot have implicit operands");
+ const Value *Op = MI->getImplicitRef(i);
+
+ if (Op->getType() == Type::LabelTy) // don't process labels
+ continue;
+
+ if (MI->getImplicitOp(i).isUse())
+ addUse(Op);
+ }
+ } // for all machine instructions
+}
+
+
+
+//-----------------------------------------------------------------------------
+// To add an operand which is a def
+//-----------------------------------------------------------------------------
+void BBLiveVar::addDef(const Value *Op) {
+ DefSet.insert(Op); // operand is a def - so add to def set
+ InSet.erase(Op); // this definition kills any later uses
+ InSetChanged = true;
+
+ if (DEBUG_LV >= LV_DEBUG_Verbose) std::cerr << " +Def: " << RAV(Op) << "\n";
+}
+
+
+//-----------------------------------------------------------------------------
+// To add an operand which is a use
+//-----------------------------------------------------------------------------
+void BBLiveVar::addUse(const Value *Op) {
+ InSet.insert(Op); // An operand is a use - so add to use set
+ DefSet.erase(Op); // remove if there is a def below this use
+ InSetChanged = true;
+
+ if (DEBUG_LV >= LV_DEBUG_Verbose) std::cerr << " Use: " << RAV(Op) << "\n";
+}
+
+
+//-----------------------------------------------------------------------------
+// Applies the transfer function to a basic block to produce the InSet using
+// the OutSet.
+//-----------------------------------------------------------------------------
+
+bool BBLiveVar::applyTransferFunc() {
+ // IMPORTANT: caller should check whether the OutSet changed
+ // (else no point in calling)
+
+ ValueSet OutMinusDef = set_difference(OutSet, DefSet);
+ InSetChanged = set_union(InSet, OutMinusDef);
+
+ OutSetChanged = false; // no change to OutSet since transf func applied
+ return InSetChanged;
+}
+
+
+//-----------------------------------------------------------------------------
+// calculates Out set using In sets of the successors
+//-----------------------------------------------------------------------------
+
+bool BBLiveVar::setPropagate(ValueSet *OutSet, const ValueSet *InSet,
+ const BasicBlock *PredBB) {
+ bool Changed = false;
+
+ // merge all members of InSet into OutSet of the predecessor
+ for (ValueSet::const_iterator InIt = InSet->begin(), InE = InSet->end();
+ InIt != InE; ++InIt)
+ if ((OutSet->insert(*InIt)).second)
+ Changed = true;
+
+ //
+ //**** WARNING: The following code for handling dummy PHI machine
+ // instructions is untested. See explanation above.
+ //
+ // then merge all members of the EdgeInSet for the predecessor into the OutSet
+ const ValueSet& EdgeInSet = PredToEdgeInSetMap[PredBB];
+ for (ValueSet::const_iterator InIt = EdgeInSet.begin(), InE = EdgeInSet.end();
+ InIt != InE; ++InIt)
+ if ((OutSet->insert(*InIt)).second)
+ Changed = true;
+ //
+ //****
+
+ return Changed;
+}
+
+
+//-----------------------------------------------------------------------------
+// propagates in set to OutSets of PREDECESSORs
+//-----------------------------------------------------------------------------
+
+bool BBLiveVar::applyFlowFunc(hash_map<const BasicBlock*,
+ BBLiveVar*> &BBLiveVarInfo) {
+ // IMPORTANT: caller should check whether inset changed
+ // (else no point in calling)
+
+ // If this BB changed any OutSets of preds whose POID is lower, than we need
+ // another iteration...
+ //
+ bool needAnotherIt = false;
+
+ for (pred_const_iterator PI = pred_begin(&BB), PE = pred_end(&BB);
+ PI != PE ; ++PI) {
+ BBLiveVar *PredLVBB = BBLiveVarInfo[*PI];
+
+ // do set union
+ if (setPropagate(&PredLVBB->OutSet, &InSet, *PI)) {
+ PredLVBB->OutSetChanged = true;
+
+ // if the predec POID is lower than mine
+ if (PredLVBB->getPOId() <= POID)
+ needAnotherIt = true;
+ }
+ } // for
+
+ return needAnotherIt;
+}
+
+
+
+// ----------------- Methods For Debugging (Printing) -----------------
+
+void BBLiveVar::printAllSets() const {
+ std::cerr << " Defs: "; printSet(DefSet); std::cerr << "\n";
+ std::cerr << " In: "; printSet(InSet); std::cerr << "\n";
+ std::cerr << " Out: "; printSet(OutSet); std::cerr << "\n";
+}
+
+void BBLiveVar::printInOutSets() const {
+ std::cerr << " In: "; printSet(InSet); std::cerr << "\n";
+ std::cerr << " Out: "; printSet(OutSet); std::cerr << "\n";
+}
+
+} // End llvm namespace