6502/llvm-6502
1
0
Fork 0
mirror of https://github.com/c64scene-ar/llvm-6502.git synced 2025-07-28 19:25:00 +00:00
Code Issues Projects Releases Wiki Activity

Remove RegisterScavenger::isSuperRegUsed(). This completely reverses the mistaken commit r77904.

Browse Source 
Now there is no special treatment of instructions that redefine part of a
super-register. Instead, the super-register is marked with <imp-use,kill> and
<imp-def>. For instance, from LowerSubregs on ARM:

subreg: CONVERTING: %Q1<def> = INSERT_SUBREG %Q1<undef>, %D1<kill>, 5
subreg: %D2<def> = FCPYD %D1<kill>, 14, %reg0, %Q1<imp-def>

subreg: CONVERTING: %Q1<def> = INSERT_SUBREG %Q1, %D0<kill>, 6
subreg: %D3<def> = FCPYD %D0<kill>, 14, %reg0, %Q1<imp-use,kill>, %Q1<imp-def>

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@78466 91177308-0d34-0410-b5e6-96231b3b80d8
This commit is contained in:
Jakob Stoklund Olesen
2009-08-08 13:19:10 +00:00
parent dffb051c21
commit 9390cd0e86
3 changed files with 9 additions and 41 deletions
Download Patch File Download Diff File Expand all files Collapse all files

13
lib/CodeGen/LowerSubregs.cpp
View File

@@ -270,14 +270,15 @@ bool LowerSubregsInstructionPass::LowerInsert(MachineInstr *MI) {
MachineBasicBlock::iterator CopyMI = MI;
--CopyMI;
// INSERT_SUBREG is a two-address instruction so it implicitly kills SrcReg.
if (!MI->getOperand(1).isUndef())
CopyMI->addOperand(MachineOperand::CreateReg(DstReg, false, true, true));
// Transfer the kill/dead flags, if needed.
if (MI->getOperand(0).isDead()) {
TransferDeadFlag(MI, DstSubReg, TRI);
// Also add a SrcReg<imp-kill> of the super register.
CopyMI->addOperand(MachineOperand::CreateReg(DstReg, false, true, true));
} else if (MI->getOperand(1).isUndef()) {
// If SrcReg was marked <undef> we must make sure it is alive after this
// replacement. Add a SrcReg<imp-def> operand.
} else {
// Make sure the full DstReg is live after this replacement.
CopyMI->addOperand(MachineOperand::CreateReg(DstReg, true, true));
}
@@ -293,7 +294,7 @@ bool LowerSubregsInstructionPass::LowerInsert(MachineInstr *MI) {
DOUT << "\n";
MBB->erase(MI);
return true;
return true;
}
/// runOnMachineFunction - Reduce subregister inserts and extracts to register