This should be more correct: invalidates physical registers that are used in

an instruction to avoid using them to allocate to other virtual registers.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@5013 91177308-0d34-0410-b5e6-96231b3b80d8
This commit is contained in:
Misha Brukman 2002-12-13 11:33:22 +00:00
parent 7d25589ee1
commit 972b03fa53

View File

@ -79,6 +79,36 @@ namespace {
RegClassIdx.clear();
}
/// Invalidates any references, real or implicit, to physical registers
///
void invalidatePhysRegs(const MachineInstr *MI) {
unsigned Opcode = MI->getOpcode();
const MachineInstrInfo &MII = TM.getInstrInfo();
const MachineInstrDescriptor &Desc = MII.get(Opcode);
const unsigned *regs = Desc.ImplicitUses;
while (*regs)
RegsUsed[*regs++] = 1;
regs = Desc.ImplicitDefs;
while (*regs)
RegsUsed[*regs++] = 1;
/*
for (int i = MI->getNumOperands() - 1; i >= 0; --i) {
const MachineOperand &op = MI->getOperand(i);
if (op.isMachineRegister())
RegsUsed[op.getAllocatedRegNum()] = 1;
}
for (int i = MI->getNumImplicitRefs() - 1; i >= 0; --i) {
const MachineOperand &op = MI->getImplicitOp(i);
if (op.isMachineRegister())
RegsUsed[op.getAllocatedRegNum()] = 1;
}
*/
}
void cleanupAfterFunction() {
RegMap.clear();
SSA2PhysRegMap.clear();
@ -222,6 +252,12 @@ bool RegAllocSimple::runOnMachineFunction(MachineFunction &Fn) {
// get rid of the phi
MBB->erase(MBB->begin());
// a preliminary pass that will invalidate any registers that
// are used by the instruction (including implicit uses)
invalidatePhysRegs(MI);
DEBUG(std::cerr << "num invalid regs: " << RegsUsed.size() << "\n");
DEBUG(std::cerr << "num ops: " << MI->getNumOperands() << "\n");
MachineOperand &targetReg = MI->getOperand(0);
@ -285,13 +321,13 @@ bool RegAllocSimple::runOnMachineFunction(MachineFunction &Fn) {
saveVirtRegToStack(opBlock, opI, virtualReg, opPhysReg);
}
}
// make regs available to other instructions
clearAllRegs();
}
// really delete the instruction
delete MI;
// make regs available to other instructions
clearAllRegs();
}
//loop over each basic block
@ -299,8 +335,9 @@ bool RegAllocSimple::runOnMachineFunction(MachineFunction &Fn) {
{
MachineInstr *MI = *I;
// FIXME: add a preliminary pass that will invalidate any registers that
// a preliminary pass that will invalidate any registers that
// are used by the instruction (including implicit uses)
invalidatePhysRegs(MI);
// Loop over uses, move from memory into registers
for (int i = MI->getNumOperands() - 1; i >= 0; --i) {