Simplify operand folding when rematerializing a load.

We already know how to fold a reload from a frameindex without
analyzing the load instruction. Generalize this to handle any
frameindex load. This streamlines the logic for rematerializing loads
from stack arguments. As a side effect, it allows stackmaps to record
a stack argument location without spilling it.

Verified no effect on codegen for llvm test-suite.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@194497 91177308-0d34-0410-b5e6-96231b3b80d8
This commit is contained in:
Andrew Trick
2013-11-12 18:06:12 +00:00
parent 2f08e75a45
commit 0085d5e5ae
2 changed files with 12 additions and 12 deletions

View File

@@ -4292,6 +4292,12 @@ MachineInstr* X86InstrInfo::foldMemoryOperandImpl(MachineFunction &MF,
MachineInstr *MI,
const SmallVectorImpl<unsigned> &Ops,
MachineInstr *LoadMI) const {
// If loading from a FrameIndex, fold directly from the FrameIndex.
unsigned NumOps = LoadMI->getDesc().getNumOperands();
int FrameIndex;
if (isLoadFromStackSlot(LoadMI, FrameIndex))
return foldMemoryOperandImpl(MF, MI, Ops, FrameIndex);
// Check switch flag
if (NoFusing) return NULL;
@@ -4417,7 +4423,6 @@ MachineInstr* X86InstrInfo::foldMemoryOperandImpl(MachineFunction &MF,
return NULL;
// Folding a normal load. Just copy the load's address operands.
unsigned NumOps = LoadMI->getDesc().getNumOperands();
for (unsigned i = NumOps - X86::AddrNumOperands; i != NumOps; ++i)
MOs.push_back(LoadMI->getOperand(i));
break;