llvm-6502/lib/CodeGen/ExpandISelPseudos.cpp
Eric Christopher 6035518e3b Have MachineFunction cache a pointer to the subtarget to make lookups
shorter/easier and have the DAG use that to do the same lookup. This
can be used in the future for TargetMachine based caching lookups from
the MachineFunction easily.

Update the MIPS subtarget switching machinery to update this pointer
at the same time it runs.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@214838 91177308-0d34-0410-b5e6-96231b3b80d8
2014-08-05 02:39:49 +00:00

77 lines
2.5 KiB
C++

//===-- llvm/CodeGen/ExpandISelPseudos.cpp ----------------------*- C++ -*-===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// Expand Pseudo-instructions produced by ISel. These are usually to allow
// the expansion to contain control flow, such as a conditional move
// implemented with a conditional branch and a phi, or an atomic operation
// implemented with a loop.
//
//===----------------------------------------------------------------------===//
#include "llvm/CodeGen/Passes.h"
#include "llvm/CodeGen/MachineFunction.h"
#include "llvm/CodeGen/MachineFunctionPass.h"
#include "llvm/Support/Debug.h"
#include "llvm/Target/TargetLowering.h"
#include "llvm/Target/TargetMachine.h"
#include "llvm/Target/TargetSubtargetInfo.h"
using namespace llvm;
#define DEBUG_TYPE "expand-isel-pseudos"
namespace {
class ExpandISelPseudos : public MachineFunctionPass {
public:
static char ID; // Pass identification, replacement for typeid
ExpandISelPseudos() : MachineFunctionPass(ID) {}
private:
bool runOnMachineFunction(MachineFunction &MF) override;
void getAnalysisUsage(AnalysisUsage &AU) const override {
MachineFunctionPass::getAnalysisUsage(AU);
}
};
} // end anonymous namespace
char ExpandISelPseudos::ID = 0;
char &llvm::ExpandISelPseudosID = ExpandISelPseudos::ID;
INITIALIZE_PASS(ExpandISelPseudos, "expand-isel-pseudos",
"Expand ISel Pseudo-instructions", false, false)
bool ExpandISelPseudos::runOnMachineFunction(MachineFunction &MF) {
bool Changed = false;
const TargetLowering *TLI = MF.getSubtarget().getTargetLowering();
// Iterate through each instruction in the function, looking for pseudos.
for (MachineFunction::iterator I = MF.begin(), E = MF.end(); I != E; ++I) {
MachineBasicBlock *MBB = I;
for (MachineBasicBlock::iterator MBBI = MBB->begin(), MBBE = MBB->end();
MBBI != MBBE; ) {
MachineInstr *MI = MBBI++;
// If MI is a pseudo, expand it.
if (MI->usesCustomInsertionHook()) {
Changed = true;
MachineBasicBlock *NewMBB =
TLI->EmitInstrWithCustomInserter(MI, MBB);
// The expansion may involve new basic blocks.
if (NewMBB != MBB) {
MBB = NewMBB;
I = NewMBB;
MBBI = NewMBB->begin();
MBBE = NewMBB->end();
}
}
}
}
return Changed;
}