RPCS3/llvm
1
0
Fork 0
mirror of https://github.com/RPCS3/llvm.git synced 2025-01-07 12:30:57 +00:00
Code Issues Actions Packages Projects Releases Wiki Activity

[SystemZ] Use LDE32 instead of LE, when Offset is small.

Browse Source 
On z13, if eliminateFrameIndex() chooses LE (and not LEY), immediately
transform that LE to LDE32 to avoid partial register dependencies.

LEY should be generally preferred for big offsets over an expansion
into LAY + LDE32.

Reviewed by Ulrich Weigand.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@266060 91177308-0d34-0410-b5e6-96231b3b80d8
This commit is contained in:
Jonas Paulsson 2016-04-12 12:07:23 +00:00
parent b3bccda2dc
commit ef1a3d2607
1 changed files with 7 additions and 1 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

8
lib/Target/SystemZ/SystemZRegisterInfo.cpp
View File

@ -84,8 +84,14 @@ SystemZRegisterInfo::eliminateFrameIndex(MachineBasicBlock::iterator MI,
// accepts the offset exists.
unsigned Opcode = MI->getOpcode();
unsigned OpcodeForOffset = TII->getOpcodeForOffset(Opcode, Offset);
if (OpcodeForOffset)
if (OpcodeForOffset) {
if (OpcodeForOffset == SystemZ::LE &&
MF.getSubtarget<SystemZSubtarget>().hasVector()) {
// If LE is ok for offset, use LDE instead on z13.
OpcodeForOffset = SystemZ::LDE32;
}
MI->getOperand(FIOperandNum).ChangeToRegister(BasePtr, false);
}
else {
// Create an anchor point that is in range. Start at 0xffff so that
// can use LLILH to load the immediate.