//
//===----------------------------------------------------------------------===//
-#define DEBUG_TYPE "calcspillweights"
-
#include "llvm/CodeGen/CalcSpillWeights.h"
#include "llvm/CodeGen/LiveIntervalAnalysis.h"
#include "llvm/CodeGen/MachineBlockFrequencyInfo.h"
#include "llvm/Support/Debug.h"
#include "llvm/Support/raw_ostream.h"
#include "llvm/Target/TargetInstrInfo.h"
-#include "llvm/Target/TargetMachine.h"
#include "llvm/Target/TargetRegisterInfo.h"
+#include "llvm/Target/TargetSubtargetInfo.h"
using namespace llvm;
+#define DEBUG_TYPE "calcspillweights"
+
void llvm::calculateSpillWeightsAndHints(LiveIntervals &LIS,
MachineFunction &MF,
const MachineLoopInfo &MLI,
void
VirtRegAuxInfo::calculateSpillWeightAndHint(LiveInterval &li) {
MachineRegisterInfo &mri = MF.getRegInfo();
- const TargetRegisterInfo &tri = *MF.getTarget().getRegisterInfo();
- MachineBasicBlock *mbb = 0;
- MachineLoop *loop = 0;
+ const TargetRegisterInfo &tri = *MF.getSubtarget().getRegisterInfo();
+ MachineBasicBlock *mbb = nullptr;
+ MachineLoop *loop = nullptr;
bool isExiting = false;
float totalWeight = 0;
+ unsigned numInstr = 0; // Number of instructions using li
SmallPtrSet<MachineInstr*, 8> visited;
// Find the best physreg hint and the best virtreg hint.
// Don't recompute spill weight for an unspillable register.
bool Spillable = li.isSpillable();
- for (MachineRegisterInfo::reg_iterator I = mri.reg_begin(li.reg);
- MachineInstr *mi = I.skipInstruction();) {
+ for (MachineRegisterInfo::reg_instr_iterator
+ I = mri.reg_instr_begin(li.reg), E = mri.reg_instr_end();
+ I != E; ) {
+ MachineInstr *mi = &*(I++);
+ numInstr++;
if (mi->isIdentityCopy() || mi->isImplicitDef() || mi->isDebugValue())
continue;
- if (!visited.insert(mi))
+ if (!visited.insert(mi).second)
continue;
float weight = 1.0f;
unsigned hint = copyHint(mi, li.reg, tri, mri);
if (!hint)
continue;
- float hweight = Hint[hint] += weight;
+ // Force hweight onto the stack so that x86 doesn't add hidden precision,
+ // making the comparison incorrectly pass (i.e., 1 > 1 == true??).
+ //
+ // FIXME: we probably shouldn't use floats at all.
+ volatile float hweight = Hint[hint] += weight;
if (TargetRegisterInfo::isPhysicalRegister(hint)) {
if (hweight > bestPhys && mri.isAllocatable(hint))
bestPhys = hweight, hintPhys = hint;
// it is a preferred candidate for spilling.
// FIXME: this gets much more complicated once we support non-trivial
// re-materialization.
- if (isRematerializable(li, LIS, *MF.getTarget().getInstrInfo()))
+ if (isRematerializable(li, LIS, *MF.getSubtarget().getInstrInfo()))
totalWeight *= 0.5F;
- li.weight = normalize(totalWeight, li.getSize());
+ li.weight = normalize(totalWeight, li.getSize(), numInstr);
}