[AMDGPU] added SIInstrInfo::getAddNoCarry() helper

Addressed rest of post submit comments from D31993.

Differential Revision: https://reviews.llvm.org/D32057

llvm-svn: 300288

1 files changed, 13 insertions, 0 deletions

diff --git a/llvm/lib/Target/AMDGPU/SIInstrInfo.cpp b/llvm/lib/Target/AMDGPU/SIInstrInfo.cpp
index b29cfe116c8..05ac67d2662 100644
--- a/llvm/lib/Target/AMDGPU/SIInstrInfo.cpp
+++ b/llvm/lib/Target/AMDGPU/SIInstrInfo.cpp
@@ -3930,3 +3930,16 @@ bool SIInstrInfo::isBasicBlockPrologue(const MachineInstr &MI) const {
   return !MI.isTerminator() && MI.getOpcode() != AMDGPU::COPY &&
          MI.modifiesRegister(AMDGPU::EXEC, &RI);
 }
+
+MachineInstrBuilder
+SIInstrInfo::getAddNoCarry(MachineBasicBlock &MBB,
+                           MachineBasicBlock::iterator I,
+                           const DebugLoc &DL,
+                           unsigned DestReg) const {
+  MachineRegisterInfo &MRI = MBB.getParent()->getRegInfo();
+
+  unsigned UnusedCarry = MRI.createVirtualRegister(&AMDGPU::SReg_64RegClass);
+
+  return BuildMI(MBB, I, DL, get(AMDGPU::V_ADD_I32_e64), DestReg)
+           .addReg(UnusedCarry, RegState::Define | RegState::Dead);
+}