replica
/
hanchenye-llvm-project
2
0
Fork 0
Code Issues Pull Requests Projects Releases Wiki Activity

post-ra-sched: Replace a std::set of regs with a bitvector. 

Assuming that a single std::set node adds 3 control words, a bitvector
can store (3*8+4)*8=224 registers in the allocated memory of a single
element in the std::set (x86_64). Also we don't have to call malloc
for every register added.

llvm-svn: 151269
This commit is contained in:
Benjamin Kramer 2012-02-23 18:28:32 +00:00
parent 2f0de8bdb9
commit 21974b1fa6
1 changed files with 4 additions and 5 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

9
llvm/lib/CodeGen/PostRASchedulerList.cpp
View File

@ -45,7 +45,6 @@
#include "llvm/Support/raw_ostream.h"
#include "llvm/ADT/BitVector.h"
#include "llvm/ADT/Statistic.h"
#include <set>
using namespace llvm;
STATISTIC(NumNoops, "Number of noops inserted");
@ -446,7 +445,7 @@ bool SchedulePostRATDList::ToggleKillFlag(MachineInstr *MI,
void SchedulePostRATDList::FixupKills(MachineBasicBlock *MBB) {
DEBUG(dbgs() << "Fixup kills for BB#" << MBB->getNumber() << '\n');
std::set<unsigned> killedRegs;
BitVector killedRegs(TRI->getNumRegs());
BitVector ReservedRegs = TRI->getReservedRegs(MF);
StartBlockForKills(MBB);
@ -487,7 +486,7 @@ void SchedulePostRATDList::FixupKills(MachineBasicBlock *MBB) {
// Examine all used registers and set/clear kill flag. When a
// register is used multiple times we only set the kill flag on
// the first use.
killedRegs.clear();
killedRegs.reset();
for (unsigned i = 0, e = MI->getNumOperands(); i != e; ++i) {
MachineOperand &MO = MI->getOperand(i);
if (!MO.isReg() || !MO.isUse()) continue;
@ -495,7 +494,7 @@ void SchedulePostRATDList::FixupKills(MachineBasicBlock *MBB) {
if ((Reg == 0) || ReservedRegs.test(Reg)) continue;
bool kill = false;
if (killedRegs.find(Reg) == killedRegs.end()) {
if (!killedRegs.test(Reg)) {
kill = true;
// A register is not killed if any subregs are live...
for (const unsigned *Subreg = TRI->getSubRegisters(Reg);
@ -519,7 +518,7 @@ void SchedulePostRATDList::FixupKills(MachineBasicBlock *MBB) {
DEBUG(MI->dump());
}
killedRegs.insert(Reg);
killedRegs.set(Reg);
}
// Mark any used register (that is not using undef) and subregs as