WebAssemblyArgumentMove.cpp [plain text]
#include "WebAssembly.h"
#include "MCTargetDesc/WebAssemblyMCTargetDesc.h"
#include "WebAssemblyMachineFunctionInfo.h"
#include "llvm/CodeGen/MachineBlockFrequencyInfo.h"
#include "llvm/CodeGen/MachineRegisterInfo.h"
#include "llvm/CodeGen/Passes.h"
#include "llvm/Support/Debug.h"
#include "llvm/Support/raw_ostream.h"
using namespace llvm;
#define DEBUG_TYPE "wasm-argument-move"
namespace {
class WebAssemblyArgumentMove final : public MachineFunctionPass {
public:
static char ID; WebAssemblyArgumentMove() : MachineFunctionPass(ID) {}
const char *getPassName() const override {
return "WebAssembly Argument Move";
}
void getAnalysisUsage(AnalysisUsage &AU) const override {
AU.setPreservesCFG();
AU.addPreserved<MachineBlockFrequencyInfo>();
AU.addPreservedID(MachineDominatorsID);
MachineFunctionPass::getAnalysisUsage(AU);
}
bool runOnMachineFunction(MachineFunction &MF) override;
};
}
char WebAssemblyArgumentMove::ID = 0;
FunctionPass *llvm::createWebAssemblyArgumentMove() {
return new WebAssemblyArgumentMove();
}
static bool IsArgument(const MachineInstr *MI) {
switch (MI->getOpcode()) {
case WebAssembly::ARGUMENT_I32:
case WebAssembly::ARGUMENT_I64:
case WebAssembly::ARGUMENT_F32:
case WebAssembly::ARGUMENT_F64:
return true;
default:
return false;
}
}
bool WebAssemblyArgumentMove::runOnMachineFunction(MachineFunction &MF) {
DEBUG({
dbgs() << "********** Argument Move **********\n"
<< "********** Function: " << MF.getName() << '\n';
});
bool Changed = false;
MachineBasicBlock &EntryMBB = MF.front();
MachineBasicBlock::iterator InsertPt = EntryMBB.end();
for (auto MII = EntryMBB.begin(), MIE = EntryMBB.end(); MII != MIE; ++MII) {
MachineInstr *MI = MII;
if (!IsArgument(MI)) {
InsertPt = MII;
break;
}
}
for (auto I = InsertPt, E = EntryMBB.end(); I != E; ++I) {
MachineInstr *MI = I;
if (IsArgument(MI)) {
EntryMBB.insert(InsertPt, MI->removeFromParent());
Changed = true;
}
}
return Changed;
}