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authorCameron Zwarich <zwarich@apple.com>2010-12-05 21:39:42 +0000
committerCameron Zwarich <zwarich@apple.com>2010-12-05 21:39:42 +0000
commit0a3fdd6e11cd351737b4451c05ec5d794e6855cf (patch)
tree6d717071fc3dc1778e37526deb5a8ba31c642e6a /lib/CodeGen/PHIElimination.cpp
parent1324289d24a1c86c9e12c590218db42814ab0225 (diff)
Remove the PHIElimination.h header, as it is no longer needed.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@120959 91177308-0d34-0410-b5e6-96231b3b80d8
Diffstat (limited to 'lib/CodeGen/PHIElimination.cpp')
-rw-r--r--lib/CodeGen/PHIElimination.cpp63
1 files changed, 55 insertions, 8 deletions
diff --git a/lib/CodeGen/PHIElimination.cpp b/lib/CodeGen/PHIElimination.cpp
index 3bc083e70ee..2ed1c38d455 100644
--- a/lib/CodeGen/PHIElimination.cpp
+++ b/lib/CodeGen/PHIElimination.cpp
@@ -14,7 +14,6 @@
//===----------------------------------------------------------------------===//
#define DEBUG_TYPE "phielim"
-#include "PHIElimination.h"
#include "PHIEliminationUtils.h"
#include "llvm/CodeGen/LiveVariables.h"
#include "llvm/CodeGen/Passes.h"
@@ -35,6 +34,54 @@
#include <map>
using namespace llvm;
+namespace {
+ class PHIElimination : public MachineFunctionPass {
+ MachineRegisterInfo *MRI; // Machine register information
+
+ public:
+ static char ID; // Pass identification, replacement for typeid
+ PHIElimination() : MachineFunctionPass(ID) {
+ initializePHIEliminationPass(*PassRegistry::getPassRegistry());
+ }
+
+ virtual bool runOnMachineFunction(MachineFunction &Fn);
+ virtual void getAnalysisUsage(AnalysisUsage &AU) const;
+
+ private:
+ /// EliminatePHINodes - Eliminate phi nodes by inserting copy instructions
+ /// in predecessor basic blocks.
+ ///
+ bool EliminatePHINodes(MachineFunction &MF, MachineBasicBlock &MBB);
+ void LowerAtomicPHINode(MachineBasicBlock &MBB,
+ MachineBasicBlock::iterator AfterPHIsIt);
+
+ /// analyzePHINodes - Gather information about the PHI nodes in
+ /// here. In particular, we want to map the number of uses of a virtual
+ /// register which is used in a PHI node. We map that to the BB the
+ /// vreg is coming from. This is used later to determine when the vreg
+ /// is killed in the BB.
+ ///
+ void analyzePHINodes(const MachineFunction& Fn);
+
+ /// Split critical edges where necessary for good coalescer performance.
+ bool SplitPHIEdges(MachineFunction &MF, MachineBasicBlock &MBB,
+ LiveVariables &LV, MachineLoopInfo *MLI);
+
+ typedef std::pair<unsigned, unsigned> BBVRegPair;
+ typedef DenseMap<BBVRegPair, unsigned> VRegPHIUse;
+
+ VRegPHIUse VRegPHIUseCount;
+
+ // Defs of PHI sources which are implicit_def.
+ SmallPtrSet<MachineInstr*, 4> ImpDefs;
+
+ // Map reusable lowered PHI node -> incoming join register.
+ typedef DenseMap<MachineInstr*, unsigned,
+ MachineInstrExpressionTrait> LoweredPHIMap;
+ LoweredPHIMap LoweredPHIs;
+ };
+}
+
STATISTIC(NumAtomic, "Number of atomic phis lowered");
STATISTIC(NumReused, "Number of reused lowered phis");
@@ -42,16 +89,16 @@ char PHIElimination::ID = 0;
INITIALIZE_PASS(PHIElimination, "phi-node-elimination",
"Eliminate PHI nodes for register allocation", false, false)
-char &llvm::PHIEliminationID = PHIElimination::ID;
+char& llvm::PHIEliminationID = PHIElimination::ID;
-void llvm::PHIElimination::getAnalysisUsage(AnalysisUsage &AU) const {
+void PHIElimination::getAnalysisUsage(AnalysisUsage &AU) const {
AU.addPreserved<LiveVariables>();
AU.addPreserved<MachineDominatorTree>();
AU.addPreserved<MachineLoopInfo>();
MachineFunctionPass::getAnalysisUsage(AU);
}
-bool llvm::PHIElimination::runOnMachineFunction(MachineFunction &MF) {
+bool PHIElimination::runOnMachineFunction(MachineFunction &MF) {
MRI = &MF.getRegInfo();
bool Changed = false;
@@ -94,7 +141,7 @@ bool llvm::PHIElimination::runOnMachineFunction(MachineFunction &MF) {
/// EliminatePHINodes - Eliminate phi nodes by inserting copy instructions in
/// predecessor basic blocks.
///
-bool llvm::PHIElimination::EliminatePHINodes(MachineFunction &MF,
+bool PHIElimination::EliminatePHINodes(MachineFunction &MF,
MachineBasicBlock &MBB) {
if (MBB.empty() || !MBB.front().isPHI())
return false; // Quick exit for basic blocks without PHIs.
@@ -129,7 +176,7 @@ static bool isSourceDefinedByImplicitDef(const MachineInstr *MPhi,
/// atomic execution of PHIs. This lowering method is always correct all of the
/// time.
///
-void llvm::PHIElimination::LowerAtomicPHINode(
+void PHIElimination::LowerAtomicPHINode(
MachineBasicBlock &MBB,
MachineBasicBlock::iterator AfterPHIsIt) {
++NumAtomic;
@@ -328,7 +375,7 @@ void llvm::PHIElimination::LowerAtomicPHINode(
/// used in a PHI node. We map that to the BB the vreg is coming from. This is
/// used later to determine when the vreg is killed in the BB.
///
-void llvm::PHIElimination::analyzePHINodes(const MachineFunction& MF) {
+void PHIElimination::analyzePHINodes(const MachineFunction& MF) {
for (MachineFunction::const_iterator I = MF.begin(), E = MF.end();
I != E; ++I)
for (MachineBasicBlock::const_iterator BBI = I->begin(), BBE = I->end();
@@ -338,7 +385,7 @@ void llvm::PHIElimination::analyzePHINodes(const MachineFunction& MF) {
BBI->getOperand(i).getReg())];
}
-bool llvm::PHIElimination::SplitPHIEdges(MachineFunction &MF,
+bool PHIElimination::SplitPHIEdges(MachineFunction &MF,
MachineBasicBlock &MBB,
LiveVariables &LV,
MachineLoopInfo *MLI) {