[llvm] [AMDGPU] Extend zero initialization of return values for TFE (PR #85759)

[David Stuttard via llvm-commits]

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@@ -15033,57 +15033,66 @@ SDNode *SITargetLowering::PostISelFolding(MachineSDNode *Node,
 // result register that will be written in the case of a memory access failure.
 // The required code is also added to tie this init code to the result of the
 // img instruction.
-void SITargetLowering::AddIMGInit(MachineInstr &MI) const {
+void SITargetLowering::AddMemOpInit(MachineInstr &MI) const {
   const SIInstrInfo *TII = getSubtarget()->getInstrInfo();
   const SIRegisterInfo &TRI = TII->getRegisterInfo();
   MachineRegisterInfo &MRI = MI.getMF()->getRegInfo();
   MachineBasicBlock &MBB = *MI.getParent();
 
-  MachineOperand *TFE = TII->getNamedOperand(MI, AMDGPU::OpName::tfe);
-  MachineOperand *LWE = TII->getNamedOperand(MI, AMDGPU::OpName::lwe);
-  MachineOperand *D16 = TII->getNamedOperand(MI, AMDGPU::OpName::d16);
+  int DstIdx =
+      AMDGPU::getNamedOperandIdx(MI.getOpcode(), AMDGPU::OpName::vdata);
+  unsigned InitIdx = 0;
 
-  if (!TFE && !LWE) // intersect_ray
-    return;
+  if (TII->isImage(MI)) {
+    MachineOperand *TFE = TII->getNamedOperand(MI, AMDGPU::OpName::tfe);
+    MachineOperand *LWE = TII->getNamedOperand(MI, AMDGPU::OpName::lwe);
+    MachineOperand *D16 = TII->getNamedOperand(MI, AMDGPU::OpName::d16);
 
-  unsigned TFEVal = TFE ? TFE->getImm() : 0;
-  unsigned LWEVal = LWE ? LWE->getImm() : 0;
-  unsigned D16Val = D16 ? D16->getImm() : 0;
+    if (!TFE && !LWE) // intersect_ray
+      return;
 
-  if (!TFEVal && !LWEVal)
-    return;
+    unsigned TFEVal = TFE ? TFE->getImm() : 0;
+    unsigned LWEVal = LWE ? LWE->getImm() : 0;
+    unsigned D16Val = D16 ? D16->getImm() : 0;
 
-  // At least one of TFE or LWE are non-zero
-  // We have to insert a suitable initialization of the result value and
-  // tie this to the dest of the image instruction.
+    if (!TFEVal && !LWEVal)
+      return;
 
-  const DebugLoc &DL = MI.getDebugLoc();
+    // At least one of TFE or LWE are non-zero
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dstutt wrote:

Yes, see the previous comment. 

https://github.com/llvm/llvm-project/pull/85759