Added PHI Def & Kill tracking to PHIElimination pass.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@76849 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/CodeGen/PHIElimination.h b/lib/CodeGen/PHIElimination.h
index 26a3731..b06435f 100644
--- a/lib/CodeGen/PHIElimination.h
+++ b/lib/CodeGen/PHIElimination.h
@@ -10,6 +10,8 @@
#ifndef LLVM_CODEGEN_PHIELIMINATION_HPP
#define LLVM_CODEGEN_PHIELIMINATION_HPP
+#include "llvm/ADT/DenseMap.h"
+#include "llvm/ADT/SmallSet.h"
#include "llvm/ADT/SmallPtrSet.h"
#include "llvm/CodeGen/MachineFunctionPass.h"
#include "llvm/Target/TargetInstrInfo.h"
@@ -21,8 +23,17 @@
/// Lower PHI instructions to copies.
class PHIElimination : public MachineFunctionPass {
MachineRegisterInfo *MRI; // Machine register information
+ private:
+
+ typedef SmallSet<MachineBasicBlock*, 4> PHIKillList;
+ typedef DenseMap<unsigned, PHIKillList> PHIKillMap;
+ typedef DenseMap<unsigned, MachineBasicBlock*> PHIDefMap;
public:
+
+ typedef PHIKillList::iterator phi_kill_iterator;
+ typedef PHIKillList::const_iterator const_phi_kill_iterator;
+
static char ID; // Pass identification, replacement for typeid
PHIElimination() : MachineFunctionPass(&ID) {}
@@ -30,6 +41,38 @@
virtual void getAnalysisUsage(AnalysisUsage &AU) const;
+ /// Return true if the given vreg was defined by a PHI intsr prior to
+ /// lowering.
+ bool hasPHIDef(unsigned vreg) const {
+ return PHIDefs.count(vreg);
+ }
+
+ /// Returns the block in which the PHI instruction which defined the
+ /// given vreg used to reside.
+ MachineBasicBlock* getPHIDefBlock(unsigned vreg) {
+ PHIDefMap::iterator phiDefItr = PHIDefs.find(vreg);
+ assert(phiDefItr != PHIDefs.end() && "vreg has no phi-def.");
+ return phiDefItr->second;
+ }
+
+ /// Returns true if the given vreg was killed by a PHI instr.
+ bool hasPHIKills(unsigned vreg) const {
+ return PHIKills.count(vreg);
+ }
+
+ /// Returns an iterator over the BasicBlocks which contained PHI
+ /// kills of this register prior to lowering.
+ phi_kill_iterator phiKillsBegin(unsigned vreg) {
+ PHIKillMap::iterator phiKillItr = PHIKills.find(vreg);
+ assert(phiKillItr != PHIKills.end() && "vreg has no phi-kills.");
+ return phiKillItr->second.begin();
+ }
+ phi_kill_iterator phiKillsEnd(unsigned vreg) {
+ PHIKillMap::iterator phiKillItr = PHIKills.find(vreg);
+ assert(phiKillItr != PHIKills.end() && "vreg has no phi-kills.");
+ return phiKillItr->second.end();
+ }
+
private:
/// EliminatePHINodes - Eliminate phi nodes by inserting copy instructions
/// in predecessor basic blocks.
@@ -70,6 +113,8 @@
typedef std::map<BBVRegPair, unsigned> VRegPHIUse;
VRegPHIUse VRegPHIUseCount;
+ PHIDefMap PHIDefs;
+ PHIKillMap PHIKills;
// Defs of PHI sources which are implicit_def.
SmallPtrSet<MachineInstr*, 4> ImpDefs;