style changes, small fix

Author: mihajlovicana

llvm/lib/Target/AMDGPU/AMDGPUWaitSGPRHazards.cpp

@@ -190,19 +190,18 @@ class AMDGPUWaitSGPRHazards {
  return Mask;
  }
 
- bool mergeSubsequentWaitAlus(MachineBasicBlock::instr_iterator &MI,
- unsigned Mask) {
+ bool mergeConsecutiveWaitAlus(MachineBasicBlock::instr_iterator &MI,
+  unsigned Mask) {
  auto MBB = MI->getParent();
- if (MI != MBB->instr_begin()) {
- MachineBasicBlock::instr_iterator It = std::prev(MI);
- while (It != MBB->instr_begin() && It->isDebugInstr())
- --It;
- if (It->getOpcode() == AMDGPU::S_WAITCNT_DEPCTR) {
- It->getOperand(0).setImm(mergeMasks(Mask, It->getOperand(0).getImm()));
- return true;
- }
- }
- return false;
+ if (MI == MBB->instr_begin())
+ return false;
+
+ auto It = prev_nodbg(MI, MBB->instr_begin());
+ if (It->getOpcode() != AMDGPU::S_WAITCNT_DEPCTR)
+ return false;
+
+ It->getOperand(0).setImm(mergeMasks(Mask, It->getOperand(0).getImm()));
+ return true;
  }
 
  bool runOnMachineBasicBlock(MachineBasicBlock &MBB, bool Emit) {
@@ -403,7 +402,7 @@ class AMDGPUWaitSGPRHazards {
  Mask = AMDGPU::DepCtr::encodeFieldVaSdst(Mask, 0);
  }
  if (Emit) {
- if (!mergeSubsequentWaitAlus(MI, Mask)) {
+ if (!mergeConsecutiveWaitAlus(MI, Mask)) {
  auto NewMI = BuildMI(MBB, MI, MI->getDebugLoc(),
  TII->get(AMDGPU::S_WAITCNT_DEPCTR))
  .addImm(Mask);

llvm/lib/Target/AMDGPU/Utils/AMDGPUBaseInfo.cpp

@@ -1805,15 +1805,15 @@ unsigned encodeFieldVaSsrc(unsigned Encoded, unsigned VaSsrc) {
 }
 
 unsigned encodeFieldVaSsrc(unsigned VaSsrc) {
- return encodeFieldVaSsrc(0xfff, VaSsrc);
+ return encodeFieldVaSsrc(0xffff, VaSsrc);
 }
 
 unsigned encodeFieldHoldCnt(unsigned Encoded, unsigned HoldCnt) {
  return packBits(HoldCnt, Encoded, getHoldCntBitShift(), getHoldCntWidth());
 }
 
 unsigned encodeFieldHoldCnt(unsigned HoldCnt) {
- return encodeFieldHoldCnt(0xfff, HoldCnt);
+ return encodeFieldHoldCnt(0xffff, HoldCnt);
 }
 
 } // namespace DepCtr

llvm/test/CodeGen/AMDGPU/merge-consecutive-wait-alus.mir

@@ -76,3 +76,4 @@ body: |
  DBG_VALUE $sgpr0
  renamable $vgpr0 = V_CNDMASK_B32_e64 0, -1, 0, killed $vgpr0, killed $sgpr0, implicit $exec, implicit-def $vcc
 ...
+