detach from llvm#110653

Author: VyacheslavLevytskyy

llvm/lib/Target/SPIRV/SPIRVInstrInfo.cpp

@@ -197,9 +197,9 @@ bool SPIRVInstrInfo::analyzeBranch(MachineBasicBlock &MBB,
   } else if (MI->getOpcode() == SPIRV::OpBranchConditional) {
     Cond.push_back(MI->getOperand(0));
     TBB = MI->getOperand(1).getMBB();
-    FBB = MI->getOperand(2).getMBB();
-    for (unsigned I = 3, E = MI->getNumOperands(); I < E; ++I)
-      Cond.push_back(MI->getOperand(I));
+    if (MI->getNumOperands() == 3) {
+      FBB = MI->getOperand(2).getMBB();
+    }
     return false;
   } else {
     return true;
@@ -212,17 +212,9 @@ bool SPIRVInstrInfo::analyzeBranch(MachineBasicBlock &MBB,
 // If \p BytesRemoved is non-null, report the change in code size from the
 // removed instructions.
 unsigned SPIRVInstrInfo::removeBranch(MachineBasicBlock &MBB,
-                                      int * /*BytesRemoved*/) const {
-  MachineBasicBlock::iterator I = MBB.getLastNonDebugInstr();
-  if (I == MBB.end())
-    return 0;
-
-  unsigned Opcode = I->getOpcode();
-  if (Opcode == SPIRV::OpBranch || Opcode == SPIRV::OpBranchConditional) {
-    I->eraseFromParent();
-    return 1;
-  }
-  return 0;
+                                      int *BytesRemoved) const {
+  report_fatal_error("Branch removal not supported, as MBB info not propagated"
+                     " to OpPhi instructions. Try using -O0 instead.");
 }
 
 // Insert branch code into the end of the specified MachineBasicBlock. The
@@ -238,25 +230,12 @@ unsigned SPIRVInstrInfo::removeBranch(MachineBasicBlock &MBB,
 //
 // The CFG information in MBB.Predecessors and MBB.Successors must be valid
 // before calling this function.
-unsigned SPIRVInstrInfo::insertBranch(MachineBasicBlock &MBB,
-                                      MachineBasicBlock *TBB,
-                                      MachineBasicBlock *FBB,
-                                      ArrayRef<MachineOperand> Cond,
-                                      const DebugLoc &DL,
-                                      int * /*BytesAdded*/) const {
-  if (!TBB)
-    return 0;
-  if (Cond.empty()) {
-    BuildMI(&MBB, DL, get(SPIRV::OpBranch)).addMBB(TBB);
-  } else {
-    auto MIB = BuildMI(&MBB, DL, get(SPIRV::OpBranchConditional))
-                   .add(Cond[0])
-                   .addMBB(TBB)
-                   .addMBB(FBB);
-    for (unsigned i = 1; i < Cond.size(); ++i)
-      MIB.add(Cond[i]);
-  }
-  return 1;
+unsigned SPIRVInstrInfo::insertBranch(
+    MachineBasicBlock &MBB, MachineBasicBlock *TBB, MachineBasicBlock *FBB,
+    ArrayRef<MachineOperand> Cond, const DebugLoc &DL, int *BytesAdded) const {
+  report_fatal_error("Branch insertion not supported, as MBB info not "
+                     "propagated to OpPhi instructions. Try using "
+                     "-O0 instead.");
 }
 
 void SPIRVInstrInfo::copyPhysReg(MachineBasicBlock &MBB,