Use a DenseMap for mapping reg->reg. This improves the LiveInterval
analysis running time from 2.7869secs to 2.5226secs on 176.gcc.
llvm-svn: 16244
diff --git a/llvm/lib/CodeGen/LiveIntervalAnalysis.h b/llvm/lib/CodeGen/LiveIntervalAnalysis.h
index 73d730a..b90be62 100644
--- a/llvm/lib/CodeGen/LiveIntervalAnalysis.h
+++ b/llvm/lib/CodeGen/LiveIntervalAnalysis.h
@@ -20,6 +20,7 @@
#ifndef LLVM_CODEGEN_LIVEINTERVAL_ANALYSIS_H
#define LLVM_CODEGEN_LIVEINTERVAL_ANALYSIS_H
+#include "llvm/ADT/DenseMap.h"
#include "llvm/CodeGen/MachineFunctionPass.h"
#include "LiveInterval.h"
@@ -44,7 +45,7 @@
typedef std::map<unsigned, LiveInterval> Reg2IntervalMap;
Reg2IntervalMap r2iMap_;
- typedef std::map<unsigned, unsigned> Reg2RegMap;
+ typedef DenseMap<unsigned> Reg2RegMap;
Reg2RegMap r2rMap_;
std::vector<bool> allocatableRegs_;
@@ -171,11 +172,11 @@
}
/// rep - returns the representative of this register
- unsigned rep(unsigned reg) {
- Reg2RegMap::iterator it = r2rMap_.find(reg);
- if (it != r2rMap_.end())
- return it->second = rep(it->second);
- return reg;
+ unsigned rep(unsigned Reg) {
+ unsigned Rep = r2rMap_[Reg];
+ if (Rep)
+ return r2rMap_[Reg] = rep(Rep);
+ return Reg;
}
void printRegName(unsigned reg) const;