#include <algorithm>
-#define DEBUG_TYPE "x86-pad-short-functions"
#include "X86.h"
#include "X86InstrInfo.h"
+#include "X86Subtarget.h"
#include "llvm/ADT/Statistic.h"
#include "llvm/CodeGen/MachineFunctionPass.h"
#include "llvm/CodeGen/MachineInstrBuilder.h"
using namespace llvm;
+#define DEBUG_TYPE "x86-pad-short-functions"
+
STATISTIC(NumBBsPadded, "Number of basic blocks padded");
namespace {
struct PadShortFunc : public MachineFunctionPass {
static char ID;
PadShortFunc() : MachineFunctionPass(ID)
- , Threshold(4), TM(0), TII(0) {}
+ , Threshold(4), STI(nullptr), TII(nullptr) {}
- virtual bool runOnMachineFunction(MachineFunction &MF);
+ bool runOnMachineFunction(MachineFunction &MF) override;
- virtual const char *getPassName() const {
+ const char *getPassName() const override {
return "X86 Atom pad short functions";
}
// VisitedBBs - Cache of previously visited BBs.
DenseMap<MachineBasicBlock*, VisitedBBInfo> VisitedBBs;
- const TargetMachine *TM;
+ const X86Subtarget *STI;
const TargetInstrInfo *TII;
};
/// runOnMachineFunction - Loop over all of the basic blocks, inserting
/// NOOP instructions before early exits.
bool PadShortFunc::runOnMachineFunction(MachineFunction &MF) {
- const AttributeSet &FnAttrs = MF.getFunction()->getAttributes();
- if (FnAttrs.hasAttribute(AttributeSet::FunctionIndex,
- Attribute::OptimizeForSize) ||
- FnAttrs.hasAttribute(AttributeSet::FunctionIndex,
- Attribute::MinSize)) {
+ if (MF.getFunction()->optForSize()) {
return false;
}
- TM = &MF.getTarget();
- TII = TM->getInstrInfo();
+ STI = &MF.getSubtarget<X86Subtarget>();
+ if (!STI->padShortFunctions())
+ return false;
+
+ TII = STI->getInstrInfo();
// Search through basic blocks and mark the ones that have early returns
ReturnBBs.clear();
VisitedBBs.clear();
- findReturns(MF.begin());
+ findReturns(&MF.front());
bool MadeChange = false;
return true;
}
- CyclesToEnd += TII->getInstrLatency(TM->getInstrItineraryData(), MI);
+ CyclesToEnd += TII->getInstrLatency(STI->getInstrItineraryData(), MI);
}
VisitedBBs[MBB] = VisitedBBInfo(false, CyclesToEnd);